WO2018088933A1

WO2018088933A1 - Anti-tumor effects of a viral vector encoding a toll-like receptor and a toll-like receptor agonist

Info

Publication number: WO2018088933A1
Application number: PCT/RU2017/000688
Authority: WO
Inventors: Vadim Mett
Original assignee: Limited Liability Company "Panacela Labs"
Priority date: 2016-11-14
Filing date: 2017-09-21
Publication date: 2018-05-17
Also published as: RU2741228C2; RU2019110898A3; RU2019110898A

Abstract

The present invention provides compositions comprising viral vectors encoding a toll-like receptor (TLR) and a TLR agonist and use of the compositions for the prevention and treatment of prostate cancer

Description

ANTI-TUMOR EFFECTS OF A VIRAL VECTOR ENCODING A TOLL-LIKE RECEPTOR AND A TOLL-LIKE

RECEPTOR AGONIST

FIELD

The present invention relates, in part, to compositions comprising viral vectors encoding a toll-like receptor (TLR) and a TLR agonist and use of the compositions for the prevention and treatment of prostate cancer.

BACKGROUND

Prostate cancer is the third leading cause of cancer deaths among men in the United States. The number of new cases of prostate cancer, estimated at more than 220,000 per year in 2005, is expected to increase to more than 380,000 by 2025 due to the aging male population. Currently, primary prostate cancer is treated by surgery, radiation, hormone therapy, or a combination of these treatment modalities. The choice for treatment depends on the age and/or operability of the patient, and the patient's tolerance for the specific treatment-related side-effects (inclusive of, for example, impotence). For a significant fraction of patients with prostate cancers, the existing therapies only provide a temporary relief of the symptoms, while the castration-resistant and/or metastatic forms of prostate cancer develop. Currently, there are no effective pharmacological therapies for advanced prostate cancer. Recent developments of prostate cancer vaccines such as Sipuleucel-T have demonstrated limited efficacy but none extended survival for more than a few months.

Accordingly, there remains an urgent need for improved methods and compositions for the prevention and treatment of prostate cancer. SUMMARY

In one aspect, the present invention relates to methods of preventing and/or treating prostate cancer in a subject. In various embodiments, the methods of the invention utilize a vector comprising a first and second nucleic acid, wherein the first nucleic acid encodes a toll-like receptor and the second nucleic acid encodes a toll-like receptor agonist. In various embodiments, the methods of the invention utilize a cell transduced with the vector described herein. In an embodiment, the vector may be a mammalian expression vector. In an embodiment, the vector may be an adenovirus vector. In various embodiments, the first nucleic acid encodes for a toll-like receptor (TLR). In an embodiment, the TLR is TLR-5 such as human TLR-5. In various embodiments, the second nucleic acid may encode for a toll-like receptor agonist that is a flagellin. In an embodiment, the flagellin is a secreted form of flagellin such as CBLB502S. In another embodiment, the flagellin is an unglycosylated secreted form of flagellin such as CBLB502NQS. In various embodiments, the methods of the invention prevent and/or treat prostate cancer. In some embodiments, methods of the invention prevent or reduce pre-cancerous changes in the prostate of a subject. In some embodiments, methods of the invention treat prostate cancer including prostate adenocarcinoma, prostate small cell carcinoma, prostate squamous cell carcinoma, prostatic sarcoma, prostate transitional cell carcinoma, and/or benign prostatic hyperplasia (BPH). In some embodiments, methods of the invention prevents prostate cancer metastasis to one or more of lymph nodes, lungs, bones including spinal columns, livers, and/or the brain. In some embodiments, the present invention provides methods of reducing the recurrence of prostate cancer in a subject.

In various embodiments, the present methods are useful as an adjuvant to treatments that are alternatives to resection, e.g. in patients that refuse to have such surgery, such as radiation treatments or "wait and see" approaches. For instance, such present methods help to mitigate the likelihood or recurrence or metastasis despite the selection of a less aggressive treatment modality by a healthcare provider.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGURE 1, panels a-c, show schematic representations of expression cassettes of Mobilan M-0 (panel a), Mobilan M-VM3 (panel b), and -Ad-mCherry control (panel c). P - promoter, T - transcription terminator. Panel d shows the amino acid sequence of a secreted form of a flagellin variant i.e., CBLB502S with four potential glycosylation sites having asparagine (N) residues.

FIGURE 2 shows the percent of C57BIJ6 tumor-free mice after immunization with TRAMP C2 cells infected with M- VM3 or a control adenovirus Ad-mCherry. As controls, mice were also immunized with uninfected not were not vaccinated. The histograms from left to right are, not vaccinated, uninfected, Ad-mCherry infected, or M-VM3 infected.

FIGURE 3 provides a Kaplan-Meier curve showing mice survival after intratumoral M-VM3 (or control virus or PBS) injection followed by surgical removal of tumors.

FIGURE 4 shows the domain structure of bacterial flagellin. The Ca backbone trace, hydrophobic core distribution and structural information of F41. Four distinct hydrophobic cores that define domains D1, D2a, D2b and D3. All the hydrophobic side-chain atoms are displayed with the Ca backbone. Position and region of various structural features in the amino-acid sequence of flagellin. Shown are, from top to bottom: the F41 fragment; three b-folium folds; the secondary structure distribution with a-helix, b-structure, and b-turn; tic mark at every 50th residue; domains DO, D1, D2 and D3; the axial subunit contact region within the proto-element; the well-conserved amino-acid sequence and variable region; point mutations in F41 that produce the elements of different supercoils. Letters at the bottom indicate the morphology of mutant elements: L (D107E, R124A, R124S, G426A), L-type straight; R (A449V), R-type straight; C (D313Y, A414V, A427V, N433D), curly33.

FIGURE 5 shows a schematic of Salmonella flagellin domains, its fragments, and its interaction with TLR5. Dark bars denote regions of the flagellin gene used to construct fragments comprising A, B, C, A' and B'. FIGURE 6 depicts flagellin derivatives. The domain structure and approximate boundaries (amino acid coordinates) of selected flagellin derivatives (listed on the right). FliC flagellin of Salmonella dublin is encoded within 505 amino acids (aa).

FIGURE 7 shows the nucleotide and amino acid sequence for the following flagellin variants: AA', AB', BA', BB', CA', CB', A, B, C, GST-A', GST-B', AA'nl-170, AA'nl-163, AA'n54-170, AA'n54-163, AB'n1-170, AB'n1-163, AA'n1-129, AA'n54-129, AB'n1-129, AB'n54-129, AA'nl-100, AB'n1-100, AA'n1-70, and AB'n1-70. The pRSETb leader sequence is shown in Italic (leader includes Met, which is also amino acid 1 of FliC). The N terminal constant domain is underlined. The amino acid linker sequence is in Bold. The C terminal constant domain is underlined. GST, if present, is highlighted.

FIGURE 8, panels A and B, show a comparison of amino acid sequences of the conserved amino (panel A) and carboxy (panel B) terminus from 21 species of bacteria. The 13 conserved amino acids important for TLR5 activity are shown with shading. The amino acid sequences are identified by their accession numbers from TrEMBL (first letter=Q) or Swiss-Prot (first letter=P).

FIGURE 9 shows the amino acid sequence for the human Toll-like receptor 5 protein.

DETAILED DESCRIPTION The present invention is based on the surprising discovery that viral vectors encoding a toll-like receptor (e.g., TLR5) and a TLR agonist (e.g., an unglycosylated secreted form of flagellin - CBLB502NQs) or cells transduced with the viral vectors effectively prevented prostate tumor formation. Additionally, the viral vectors or cells transduced with the viral vectors exhibited strong anti-metastatic activities. Without wishing to be bound by theory, it is believed that delivery of the viral vectors to tumors or cells transduced with the viral vectors establishes potent autocrine/paracrine local TLR5 activation and stimulate innate and subsequent adaptive immune responses capable of suppressing growth of primary tumors and also providing long-term protection against metastases and recurrent tumors, regardless of the natural TLR5 expression status of the tumors. Accordingly, in various aspects, the present invention provides agents and compositions for use as vaccinations against prostate cancers. The present invention further provides use of the agents and compositions for the treatment of prostate cancers and for preventing prostate cancer metastasis and/or recurrence. In various embodiments, the present invention provides viral vectors encoding a toll-like receptor (TLR) and a TLR agonist. In various embodiments, the TLR may be a type of pattern recognition receptor (PRR). In some embodiments, the TLR may recognize molecules that are conserved molecular products derived from pathogens that include Gram-positive, Gram-negative bacteria, fungi, and viruses, but are distinguishable from host molecules, collectively referred to as pathogen-associated molecular patterns (PAMPs). In some embodiments, the TLR may also recognize endogenous molecules released from injured or dying cells, collectively referred to as damage- associated molecular pattern (DAMPs). A PAMP or DAMP may be a TLR agonist as further described below. In some embodiments, the TLR may be a fragment, variant, analog, homolog or derivative that recruits adapter molecules within the cytoplasm of cells in order to propagate a signal. In some embodiments, the TLR may be from a human or other mammalian species such as rhesus monkey, mouse, or rat. In some embodiments, the TLR may be at least about 30-99% identical to a TLR that recruits adapter molecules within the cytoplasm of cells in order to propagate a signal.

In various embodiments, the TLR may be one of the between ten and fifteen types of TLR that are estimated to exist in most mammalian species. The TLR may be one of the 13 TLR (named simply TLR1 to TLR13) that have been identified in humans and mice together, or may be an equivalent form that has been found in other mammalian species. In some embodiments, the TLR may be one of the 11 members (TLR1-TLR11) that have been identified in humans. In various embodiments, the TLR may be one of the TLRs described in WO2015/080631 and U.S. Patent No. 9,205,095, the entire contents of which are hereby incorporated by reference.

In various embodiments, the TLR may be expressed by different types of immune cells, and may be located on the cell surface or in the cell cytoplasm. In some embodiments, the TLR may be expressed on cancer cells. The various TLRs and their expression in cancer cells are provided below:

Table A

L ^^e l_jcjmc«__^ ___„„._„„JJ LFy^^

In various embodiments, the TLRs expressed on cancer cells may upregulate the NF-κΒ cascade and produce antj- apoptotic proteins that contribute to carcinogenesis and cancer cell proliferation.

Four adapter molecules of TLRs are known to be involved in signaling. These proteins are known as myeloid differentiation factor 88 ( yD88), Tirap (also called Mai), Trif, and Tram. The adapters activate other molecules within the cell, including certain protein kinases (IRAKI, IRAK4, TBK1, and IKKi) that amplify the signal, and ultimately lead to the induction or suppression of genes that orchestrate the inflammatory response. TLR signaling pathways during pathogen recognition may induce immune reactions via extracellular and intracellular pathways mediated by MyD88, nuclear factor kappa-light-chain-enhancer of activated B cells (NF- Β), and mitogen-associated protein kinase (MAPK). In all, thousands of genes are activated by TLR signaling, and collectively, the TLR constitute one of the most pleiotropic, yet tightly regulated gateways for gene modulation.

TLRs together with the lnterleukin-1 receptors form a receptor superfamily, known as the "lnterleukin-1 Receptor/Toll- Like Receptor Superfamily." All members of this family have in common a so-called TIR (Toll-IL-1 receptor) domain. Three subgroups of TIR domains may exist. Proteins with subgroup I TIR domains are receptors for interleukins that are produced by macrophages, monocytes and dendritic cells and all have extracellular Immunoglobulin (Ig) domains. Proteins with subgroup II TIR domains are classical TLRs, and bind directly or indirectly to molecules of microbial origin. A third subgroup of proteins containing TIR domains (III) consists of adaptor proteins that are exclusively cytosolic and mediate signaling from proteins of subgroups 1 and 2. In various embodiments, the TLR may be a fragment, variant, analog, homolog or derivative that retains either a subgroup I TIR domain, subgroup II TIR domain, or subgroup III TIR domain.

In some embodiments, the TLR may function as a dimer. For example, although most TLRs appear to function as homodimers, TLR2 forms heterodimers with TLR1 or TLR6, each dimer having a different ligand specificity. The TLR may also depend on other co-receptors for full ligand sensitivity, such as in the case of TLR4's recognition of LPS, which requires MD-2. CD14 and LPS Binding Protein (LBP) are known to facilitate the presentation of LPS to MD-2.

In a specific embodiment, the viral vectors of the invention encode Toll-like receptor 5 (TLR5). Without wishing to be bound by theory, it is believed that TLR-5 may play a fundamental role in pathogen recognition and activation of innate immunity. TLR-5 may recognize PAMPs that are expressed on infectious agents, and mediate the production of cytokines necessary for the development of effective immunity. TLR-5 may recognize bacterial flagellin, a principal component of bacterial flagella and a virulence factor. In some embodiments, the activation of the TLR may mobilize the nuclear factor NF-κΒ and stimulate tumor necrosis factor-alpha production.

In various embodiments, the viral vectors of the invention co-express a toll-like receptor (TLR) and a TLR agonist. In some embodiments, the TLR agonist is a PAMP, which may be conserved molecular product derived from a pathogen. The pathogen may be a Gram-positive bacterium, Gram-negative bacterium, fungus, or virus. In some embodiments, the TLR agonist may be a damage-associated molecular pattern (DAMP) ligand, which may be an endogenous molecule released from injured or dying cells. A DAMP or PAMP may initiate an immune response through TLR signals and recruit adapter molecules within the cytoplasm of cells in order to propagate a signal. In some embodiments, the TLR agonist may be an agonist for the TLR, which may be a ligand from the following Table B:

Table B. TLR Ligand DAMP Ligand PAM.P

Ύΰΰ Triaeyi lipoproteins

TLR2 Heat Shock proteins

HMG. 1. (high mobility group Lipoprotein

— . „ box. 1— <mip oteriri)

Li oteichoic acid

Zymosan

TLR3 Self daRNA Viral dsRNA

TL 4 Heat shock proteins Heat shock . proteins

Fibrinogen lipopoiysacciharides

Heparan sulfate RSV fusion proteie

F broriectin MTV (Mouse mammary

tumor virus) envelope proteins

Hyaluronic acid Paclitaxel

HMGB 1

T1JR5 — RageHirt

TLR6 Lipoteichoic acid

Triacyl lipoproteins

zymosan

TLR7/TLR8 Self sxRNA Viral ssRNA

Self DNA Bacteria! and viral DNA

TLR 10

TLR 11 ·————— Piofi.liii

In various embodiments, the TLR agonist may be a fragment, variant, analog, homology or derivative of a PAMP or DAMP that binds a TLR and induces TLR-mediated activity, such as activation of NF-κΒ activity. In some embodiments, the TLR agonist fragment, variant, analog, homolog, or derivative may be at least 30-99% identical to amino acids of a TLR-agonist and induce TLR-mediated activity.

In some embodiments, the TLR agonist may target a TLR such as TLR-5. The TLR agonist may be an agonist of TLR-5 and stimulate TLR-5 activity. The TLR agonist may be an anti-TLR5 antibody or other small molecule.

In some embodiments the TLR agonist may be flagellin. In some embodiments, the flagellin may be a flagellin or flagellin-related polypeptide. The flagellin may be from any source, including a variety of Gram-positive and Gram- negative bacterial species. The flagellin may be a flagellin polypeptide from any Gram-positive or Gram-negative bacterial species including, but not limited to, a flagellin polypeptide disclosed in U.S. Patent Publication No. 2003/000044429, the contents of which are fully incorporated herein by reference. For example, the flagellin may comprise an amino acid sequence from a bacterial species depicted in Figure 7 of U.S. Patent Publication No. 2003/0044429. The nucleotide sequences encoding the flagellin polypeptides listed in Figure 7 of U.S. Patent Publication No. 2003/0044429 are publicly available at sources including the NCBI Genbank database. In some embodiments, the flagellin may also be a flagellin peptide corresponding to an Accession number listed in the BLAST results shown in Figure 25 of U.S. Patent Publication No. 2003/000044429, or a variant thereof. In some embodiments, the flagellin may also be a flagellin polypeptide as disclosed in U.S. Patent Publication No. 2009/0011982, the contents of which are fully incorporated herein. In some embodiments, the flagellin maybe anyone of a flagellin polypeptide as disclosed in Figures 6 and 7 herein.

In some embodiments, the flagellin may be a fragment, variant, analog, homology or derivative of a flagellin that binds TLR5 and induces TLR5-mediated activity, such as activation of NF- Β activity. A fragment, variant, analog, homolog, or derivative of flagellin may be at least 30-99% identical to amino acids of a flagellin that binds TLR5 and induces TLR5-mediated activity.

In some embodiments, the flagellin may be from a species of Salmonella, a representative example of which is S. dublin (for example, encoded by GenBank Accession Number 84972). The flagellin related-polypeptide may be a fragment, variant, analog, homolog, or derivative of M84972, or combination thereof, that binds to TLR5 and induces TLR5-mediated activity, such as activation of NF-kB activity. A fragment, variant, analog, homolog, or derivative of flagellin may be obtained by rational-based design based on the domain structure of flagellin and the conserved structure recognized by TLR5.

In some embodiments, the flagellin may comprise at least 10, 11, 12, or 13 of the 13 conserved amino acids shown in Figure 5 (positions 89, 90, 91, 95, 98, 101, 115, 422, 423, 426, 431 , 436 and 452). In some embodiments, the flagellin may be at least 30-99% identical to amino acids 1-174 and 418-505 of M84972. Figure 26 of U.S. Patent Application Publication No. 2009/0011982, the contents of which are fully incorporated herein, lists the percentage identity of the amino- and carboxy-terminus of flagellin with known TLR-5 stimulating activity, as compared to M84972. In some embodiments, the flagellin may be the major component of bacterial flagellum. The flagellin may be composed of three domains (Figure 4). Domain 1 (D1) and domain 2 (D2) may be discontinuous and may be formed when residues in the amino terminus and carboxy terminus are juxtaposed by the formation of a hairpin structure. The amino and carboxy terminus comprising the D1 and D2 domains may be most conserved, whereas the middle hypervariable domain (D3) may be highly variable. Studies with a recombinant protein containing the amino D1 and D2 and carboxyl D1 and D2 separated by an Escherichia coli hinge (ND1-2/ECH/CD2) indicate that D1 and D2 may be bioactive when coupled to an ECH element. This chimera, but not the hinge alone, may induce IkBa degradation, NF-kB activation, and NO and IL-8 production in two intestinal epithelial cell lines. The non-conserved D3 domain may be on the surface of the flagellar filament and may contain the major antigenic epitopes. The potent proinflammatory activity of flagellin may reside in the highly conserved N and C D1 and D2 regions (See Figure 4).

The flagellin may induce NF-kB activity by binding to Toll-like receptor 5 (TLR5). The TLR may recognize a conserved structure that is particular to the flagellin. The conserved structure may be composed of a large group of residues that are somewhat permissive to variation in amino acid content. Smith et al., Nat Immunol. 4:1247-53 (2003), the contents of which are incorporated herein by reference, have identified 13 conserved amino acids in flagellin that are part of the conserved structure recognized by TLR5. The 13 conserved amino acids of flagellin that may be important for TLR5 activity are shown in Figure 5. Numerous deletion mutants of flagellin have been made that retain at least some TLR5 stimulating activity. In some embodiments, the flagellin may be such a deletion mutant, and may be a deletion mutant disclosed in the Examples of U.S. Patent No. 9,205,095, the entire contents of which are hereby incorporated by reference. The flagellin may comprise a sequence translated from GenBank Accession number D13689 missing amino acids 185-306 or 444-492, or from GenBank Accession number M84973 missing amino acids 179-415, or a variant thereof. In some embodiments, the flagellin may comprise transposon insertions and changes to the variable D3 domain. The D3 domain may be substituted in part, or in whole, with a hinge or linker polypeptide that allows the D1 and D2 domains to properly fold such that the variant stimulates TLR5 activity. The variant hinge elements may be found in the E. coli MukB protein and may have a sequence as set forth in SEQ ID NOS: 3 and 4, or a variant thereof, of U.S. Patent No. 9,205,095, the entire contents of which are hereby incorporated by reference. In some embodiments, the flagellin as described above may further comprise a leader sequence. In an embodiment, the flagellin further comprising a leader sequence may be CBLB502S. In some embodiments, the flagellin is a secreted variant as disclosed in U.S. Patent No. 9,205,095, the entire contents of which are hereby incorporated by reference. In some embodiments, the flagellin is an unglycosylated secreted form of flagellin as disclosed in WO2015/080631, the entire contents of which are hereby incorporated by reference. In an embodiment, the flagellin comprises the amino acid sequence of SEQ ID NO: 102 of WO2015/080631, otherwise referred to as CBLB502NQ.S. The CBLB502NQs variant comprises the amino acid sequence of CBLB502s as depicted in Figure 1 , panel d, with the four asparagine residues (which are potential glycosylate sites) replaced with glutamines. In an embodiment, the amino acid sequence of CBLB502NQs is as follows:

Met Ley Leu i_e» tew t*u u«« i.*u Sly Lea Aro Ley eift iu S«r i 3 ^" .10 r>

C y 6ly Ser 6^'!» ?Hs Ala ¾1R vat .i^'1e Asn r&r Asn $»f t«u Set' Leu

? 25 IS t*w Tfir fSlfi ASK ASfi tew Gin VS Ser & rs ser scr i.eu ser scr Ai&

35 40 4

Xl* Afft ea Se s«r sly tew Arg . e A*n S«r Ala Lys Asp Asp Al* «ly A1¾ l s Ala Α&π Arq t»h« Ser ASS l e Lys Cly

Lei* Tftr 61 a A a Ser Ara ssn *1« Asn Asp sly l e ser lie A3 a olfi

Hif Thr ¾ y G^'ly Ala >:.ea *¾?i i>? £t» Ase¾ As Asn Lew ¾^'ln Are s⁾

ICQ .10$ 11.0

Are slu leu Ser val <»1« Al¾ Thr «^'!« cly ? r A&a s*r &%p se Asp

U 120 25

te» Lys Ser ie Gla Asa elu lie sin s½ tew <ski ak jJ As

Af¾ val ser cln «►¼ T r Gin f'he Asn civ va ys va^'1 teu Ser Gin ftsp Asn dlft Met ys il« e1« va* sly Ala A«n Asp Gly slu f s Tie rhr tie Asp- u u Gin tvs lie AS» val ys ser ea Sly las A$# el

ISO ^' 38 s ^" 1.30

Phe Aso val SB $$ p« Glv T e SKI* Cly $1y Civ cly S^'iy lift LSU

A$P Ser «et S y Tfcr tew jl* «¾« G ii ASS Α¼ Ala Ala A¼ i.ys ty$

210 2IS ^' 220

Mr 1¾Ρ Ala Asit s*r«» Ala ser v e Asp $i»r A a t.e-u ser lys Val 225 230 23¾ 240

ASP Ala val Af-ij ser ser t*y€lv Als lie eln ASB Ar# Mte ASS sc

' 243 ^' .¾s 2SS

Ala Its ttir A$a Msu Sly As« rbr va) h .«srs tea *xn ssr Ala Ar¾

26β 26 2?0

¾3Γ Ara xU «lu Asp Ala Mp Tyr Ala Thr Gl« v*1 $*r sin Me*

• m 28«

iys A a sin t\* G n Sin .A a sly Thr &er Val ue« Ala e n *1a

2190 295ί 300

A<R 6- rt v»1 s»«5 Sin Asn val UKI S*r $»«« teu *r¾

¾f)S 3 0 31S

This invention also relates to an agent comprising a therapeutically effective amount of a TLR and TLR agonist. In some embodiments, the agent may be a vector. In some embodiments, the vector may comprise a first nucleic acid encoding the TLR and a second nucleic acid comprising the TLR agonist. The vector may be capable of transducing mammalian cells. The vector may be capable of bi-cistronic expression of the TLR and/or TLR agonist using strong promoters. The vector may comprise only a gene encoding the TLR, which may be controlled by a strong promoter. The vector may be delivered into a mammalian cell by a virus or liposome related vector system. The virus vector system may be an adenovirus or a cytomegalovirus. In an embodiment, the virus vector is an adenovirus vector. In an embodiment, the adenovirus vector is non-replicating In some embodiments, the agent may be a liposome harboring the vector. The liposome maybe capable of transducing mammalian cells and delivering the vector for expression. In some embodiments, the agent may be a nanoparticle harboring the vector. In such embodiments, the nanoparticle maybe capable of transducing mammalian cells and delivering the vector for expression.

In some embodiments, the agent may be a drug formulation that simultaneously induces expression and activates the TLR, thereby exposing tumor or infected cells to the host immune system imitating the situation of a massive penetration through the intestinal wall. The agent may be a drug formulation that expresses the TLR in combination with the TLR agonist, and may be delivered systematically in solution for administration such as intramuscularly. The agent may be a drug formulation that expresses the TLR in combination with the TLR agonist, which may be expressed from the same vector, such as an adenoviral or cytomegalovirus vector system. The agent may be a drug formulation that expresses the TLR in combination with the TLR agonist expressed in the form of a nano-particle, which may carry a functional agonist to the cell surface of a mammalian cell.

The agent may be a pharmaceutical agent comprising the drug formulation described above, which may be produced using methods well known in the art. The agent may also comprise a co-agent.

In various embodiments, the present invention provides a vector which may comprise a first nucleic acid encoding TLR5 and a second nucleic acid comprising flagellin. The vector may be capable of expressing TLR5 and/or flagellin using a strong promoter. The expression vector may further comprise a leader sequence cloned upstream of the gene encoding the TLR5 and/or flagellin. In some embodiments, the expression vector may be a pCD515 based vector system. In various embodiments, the expression vector may be any one of the vectors as described in Figure 1, panels a and b.

The agent may be a drug formulation that simultaneously induces expression and activates a TLR thereby exposing tumor or infected cells to the host immune system. The drug formulation may be in the form of a viral expression system harboring the vector. The drug formulation may be an adenovirus expressing functional human TLR5 in combination with: the TLR agonist, delivered systematically in solution for administration, such as intramuscularly; the TLR agonist, expressed from the same adenoviral vector as the TLR; or the TLR agonist, expressed in the form of nano-particles carrying functional TLR agonist, such as flagellin, which may be derived from CBLB502, on their surface, The nano-particle may be on the basis of a bacteriophage T7, or fully formed to retain its biological activity. The nano-formulation may provide for dose-dependent, NF-KB- responsive reporter activation, and may result in cell internalization by endocytosis for effective immunization approach (Mobian AP-A).

In various embodiments, administration of the agents using the method described herein may be orally, parenterally, sublingual^, transdermal^, rectally, transmucosally, topically, via inhalation, via buccal administration, or combinations thereof. Parenteral administration includes, but is not limited to, intravenous, intraarterial, intraperitoneal, subcutaneous, intramuscular, intrathecal, and intraarticular. In an embodiment, administration is intratumoral.

In some embodiments, the agent may be administered simultaneously or metronomically with other treatments. The term "simultaneous" or "simultaneously" as used herein, means that the agent and other treatment be administered within 48 hours, preferably 24 hours, more preferably 12 hours, yet more preferably 6 hours, and most preferably 3 hours or less, of each other. The term "metronomically" as used herein means the administration of the agent at times different from the other treatment and at a certain frequency relative to repeat administration.

In some embodiments, the agent may be administered at any point prior to another treatment including about 120 hours, 118 hours, 116 hours, 114 hours, 112 hours, 110 hours, 108 hours, 106 hours, 104 hours, 102 hours, 100 hours, 98 hours, 96 hours, 94 hours, 92 hours, 90 hours, 88 hours, 86 hours, 84 hours, 82 hours, 80 hours, 78 hours, 76 hours, 74 hours, 72 hours, 70 hours, 68 hours, 66 hours, 64 hours, 62 hours, 60 hours, 58 hours, 56 hours, 54 hours, 52 hours, 50 hours, 48 hours, 46 hours, 44 hours, 42 hours, 40 hours, 38 hours, 36 hours, 34 hours, 32 hours, 30 hours, 28 hours, 26 hours, 24 hours, 22 hours, 20 hours, 18 hours, 16 hours, 14 hours, 12 hours, 10 hours, 8 hours, 6 hours, 4 hours, 3 hours, 2 hours, 1 hours, 55 minutes, 50 minutes, 45 minutes, 40 minutes, 35 minutes, 30 minutes, 25 minutes, 20 minutes, 15 minutes, 10 minutes, 9 minutes, 8 minutes, 7 minutes, 6 minutes, 5 minutes, 4 minutes, 3 minutes, 2 minutes, and 1 minute. The agent may be administered at any point prior to a second treatment of the agent including about 120 hours, 118 hours, 116 hours, 114 hours, 112 hours, 110 hours, 108 hours, 106 hours, 104 hours, 102 hours, 100 hours, 98 hours, 96 hours, 94 hours, 92 hours, 90 hours, 88 hours, 86 hours, 84 hours, 82 hours, 80 hours, 78 hours, 76 hours, 74 hours, 72 hours, 70 hours, 68 hours, 66 hours, 64 hours, 62 hours, 60 hours, 58 hours, 56 hours, 54 hours, 52 hours, 50 hours, 48 hours, 46 hours, 44 hours, 42 hours, 40 hours, 38 hours, 36 hours, 34 hours, 32 hours, 30 hours, 28 hours, 26 hours, 24 hours, 22 hours, 20 hours, 18 hours, 16 hours, 14 hours, 12 hours, 10 hours, 8 hours, 6 hours, 4 hours, 3 hours, 2 hours, 1 hour, 55 minutes., 50 minutes., 45 minutes, 40 minutes, 35 minutes, 30 minutes, 25 minutes, 20 minutes, 15 minutes, 10 minutes, 9 minutes, 8 minutes, 7 minutes, 6 minutes, 5 minutes, 4 minutes, 3 minutes, 2 minutes, and 1 minute.

The agent may be administered at any point after another treatment including about 1 minutes, 2 minutes, 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, 10 minutes, 15 minutes, 20 minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, 55 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 14 hours, 16 hours, 18 hours, 20 hours, 22 hours, 24 hours, 26 hours, 28 hours, 30 hours, 32 hours, 34 hours, 36 hours, 38 hours, 40 hours, 42 hours, 44 hours, 46 hours, 48 hours, 50 hours, 52 hours, 54 hours, 56 hours, 58 hours, 60 hours, 62 hours, 64 hours, 66 hours, 68 hours, 70 hours, 72 hours, 74 hours, 76 hours, 78 hours, 80 hours, 82 hours, 84 hours, 86 hours, 88 hours, 90 hours, 92 hours, 94 hours, 96 hours, 98 hours, 100 hours, 102 hours, 104 hours, 106 hours, 108 hours, 110 hours, 112 hours, 114 hours, 116 hours, 118 hours, and 120 hours. The agent may be administered at any point after a second treatment of the agent including about 120 hours, 118 hours, 116 hours, 114 hours, 112 hours, 110 hours, 108 hours, 106 hours, 104 hours, 102 hours, 100 hours, 98 hours, 96 hours, 94 hours, 92 hours, 90 hours, 88 hours, 86 hours, 84 hours, 82 hours, 80 hours, 78 hours, 76 hours, 74 hours, 72 hours, 70 hours, 68 hours, 66 hours, 64 hours, 62 hours, 60 hours, 58 hours, 56 hours, 54 hours, 52 hours, 50 hours, 48 hours, 46 hours, 44 hours, 42 hours, 40 hours, 38 hours, 36 hours, 34 hours, 32 hours, 30 hours, 28 hours, 26 hours, 24 hours, 22 hours, 20 hours, 18 hours, 16 hours, 14 hours, 12 hours, 10 hours, 8 hours, 6 hours, 4 hours, 3 hours, 2 hours, 1 hour, 55 minutes., 50 minutes., 45 minutes, 40 minutes, 35 minutes, 30 minutes, 25 minutes, 20 minutes, 15 minutes, 10 minutes, 9 minutes, 8 minutes, 7 minutes, 6 minutes, 5 minutes, 4 minutes, 3 minutes, 2 minutes, and 1 minute.

In various embodiments, the method of the invention may comprise administering the agents provided herein may be in the form of tablets or lozenges formulated in a conventional manner. For example, tablets and capsules for oral administration may contain conventional excipients may be binding agents, fillers, lubricants, disintegrants and wetting agents. Binding agents include, but are not limited to, syrup, acacia, gelatin, sorbitol, tragacanth, mucilage of starch and polyvinylpyrrolidone. Fillers may be lactose, sugar, microcrystalline cellulose, maizestarch, calcium phosphate, and sorbitol. Lubricants include, but are not limited to, magnesium stearate, stearic acid, talc, polyethylene glycol, and silica. Disintegrants may be potato starch and sodium starch glycollate. Wetting agents may be sodium lauryl sulfate. Tablets may be coated according to methods well known in the art.

In some embodiments, the agents provided herein may also be liquid formulations such as aqueous or oily suspensions, solutions, emulsions, syrups, and elixirs. The agents may also be formulated as a dry product for constitution with water or other suitable vehicle before use. Such liquid preparations may contain additives such as suspending agents, emulsifying agents, nonaqueous vehicles and preservatives. Suspending agent may be sorbitol syrup, methyl cellulose, glucose/sugar syrup, gelatin, hydroxyethylcellulose, carboxymethyl cellulose, aluminum stearate gel, and hydrogenated edible fats. Emulsifying agents may be lecithin, sorbitan monooleate, and acacia. Nonaqueous vehicles may be edible oils, almond oil, fractionated coconut oil, oily esters, propylene glycol, and ethyl alcohol. Preservatives may be methyl or propyl p-hydroxybenzoate and sorbic acid.

In some embodiments, the agents provided herein may also be formulated as suppositories, which may contain suppository bases such as cocoa butter or glycerides. Agents provided herein may also be formulated for inhalation, which may be in a form such as a solution, suspension, or emulsion that may be administered as a dry powder or in the form of an aerosol using a propellant, such as dichlorodifluoromethane or trichlorofluoromethane. Agents provided herein may also be formulated as transdermal formulations comprising aqueous or nonaqueous vehicles such as creams, ointments, lotions, pastes, medicated plaster, patch, or membrane.

In some embodiments, the agents provided herein may also be formulated for parenteral administration such as by injection, intratumoral injection or continuous infusion. Formulations for injection may be in the form of suspensions, solutions, or emulsions in oily or aqueous vehicles, and may contain formulation agents including, but not limited to, suspending, stabilizing, and dispersing agents. The agent may also be provided in a powder form for reconstitution with a suitable vehicle including, but not limited to, sterile, pyrogen-free water.

In some embodiments, the agents provided herein may also be formulated as a depot preparation, which may be administered by implantation or by intramuscular injection, The agents may be formulated with suitable polymeric or hydrophobic materials (as an emulsion in an acceptable oil, for example), ion exchange resins, or as sparingly soluble derivatives (as a sparingly soluble salt, for example).

In various embodiments, the method of the invention may comprise administering a therapeutically effective amount of the agent to a subject in need thereof. The therapeutically effective amount required for use in therapy varies with the nature of the condition being treated, the length of time desired to activate TLR activity, and the age/condition of the subject. In various embodiments, doses employed for adult human treatment are in the range of 0.001 mg/kg to about 200 mg/kg per day. In some embodiments, the dose may be about 1 mg/kg to about 100 mg/kg per day. The desired dose may be conveniently administered in a single dose, or as multiple doses administered at appropriate intervals, for example as two, three, four or more sub-doses per day. In some embodiments, multiple doses may be desired, or required.

In various embodiments, the dosage may be at any dosage such as about 0.1 mg/kg, 0.2 mg/kg, 0.3 mg/kg, 0.4 mg/kg, 0.5 mg/kg, 0.6 mg/kg, 0.7 mg/kg, 0.8 mg/kg, 0.9 mg/kg, 1 mg/kg, 25 mg/kg, 50 mg/kg, 75 mg/kg, 100 mg/kg, 125 mg/kg, 150 mg/kg, 175 mg/kg, 200 mg/kg, 225 mg/kg, 250 mg/kg, 275 mg/kg, 300 mg/kg, 325 mg/kg, 350 mg/kg, 375 mg/kg, 400 mg/kg, 425 mg/kg, 450 mg/kg, 475 mg/kg, 500 mg/kg, 525 mg/kg, 550 mg/kg, 575 mg/kg, 600 mg/kg, 625 mg/kg, 650 mg/kg, 675 mg/kg, 700 mg/kg, 725 mg/kg, 750 mg/kg, 775 mg/kg, 800 mg/kg, 825 mg/kg, 850 mg/kg, 875 mg/kg, 900 mg/kg, 925 mg/kg, 950 mg/kg, 975 mg/kg or 1,000 mg/kg.

In one aspect, the present invention provides a method for treating cancer by administering to a mammal in need thereof the agent of the invention. Without wishing to be bound by theory, it is believed that the method provides immunotherapy against cancer by conversion of tumor cells into a TLR agonist-responsive state with targeted intratumor stimulation of TLR, thereby focusing an immune response on the tumor. The method may be used to treat primary tumors prior to surgical removal in order to reduce the risk of metastasis development, as well as treat of other tumor nodules. The method may comprise intratumor injection. The method may have the step of injecting the agent into a primary tumor prior to surgical removal to reduce the risk of metastasis development, as well as treat other tumor nodules. The method may be used to treat any tumor that is accessible for adenovirus intratumor injection.

A variety of cancers may be treated according to this invention, including carcinoma, bladder (including accelerated and metastatic bladder cancer), breast, colon (including colorectal cancer), kidney, liver, lung (including small and non-small cell lung cancer and lung adenocarcinoma), ovary, prostate, testes, genitourinary tract, lymphatic system, rectum, larynx, pancreas (including exocrine pancreatic carcinoma), esophagus, stomach, gall bladder, cervix, thyroid, and skin (including squamous cell carcinoma); hematopoietic tumors of lymphoid lineage including leukemia, acute lymphocytic leukemia, acute lymphoblastic leukemia, B-cell lymphoma, T-cell lymphoma, Hodgkins lymphoma, non-Hodgkins lymphoma, hairy cell lymphoma, histiocytic lymphoma, and Burketts lymphoma; hematopoietic tumors of myeloid lineage including acute and chronic myelogenous leukemias, myelodysplastic syndrome, myeloid leukemia, and promyelocytic leukemia; tumors of the central and peripheral nervous system including astrocytoma, neuroblastoma, glioma, and schwannomas; tumors of mesenchymal origin including fibrosarcoma, rhabdomyoscarcoma, and osteosarcoma; and other tumors including melanoma, xenoderma pigmentosum, keratoactanthoma, seminoma, thyroid follicular cancer, teratocarcinoma, and cancers of the gastrointestinal tract or the abdominopelvic cavity.

In various embodiments, the present invention provides methods of preventing and/or treating prostate cancer by administering the agent of the invention to a subject in need thereof. In some embodiments, the agent is a vector (or an adenovirus comprising the vector) that comprises a first nucleic acid encoding TLR5 and a second nucleic acid comprising an unglycosylated secreted form of flagellin {i.e., CBLB502NQs). In other embodiments, the agent is a cell transduced with a vector (or an adenovirus comprising the vector) that comprises a first nucleic acid encoding TLR5 and a second nucleic acid comprising an unglycosylated secreted form of flagellin (i.e., CBLB502NQs). In some embodiments, provided herein is a method for preventing and/or treating prostate cancer by delivery of cells transduced by the agent of the invention (e.g., an adenovirus system comprising a vector that co-expresses TLR5 and CBLB502NQs). In an embodiment, the cells may be formulated as a cell-based vaccine. In some embodiments, the method may comprise administration of the cell-based vaccine in combination with any other vaccination, which may comprise a construct expressing an antigen of choice. Exemplary cells that may be transduced by an agent of the invention (e.g., an adenovirus comprising a first nucleic acid encoding TLR5 and a second nucleic acid comprising an unglycosylated secreted form of flagellin (i.e., CBLB502NQs)) include, but are not limited to, normal, premalignant, or malignant cells. In some embodiments, the cells are obtained from the subject being treated. Exemplary cells include normal or premalignant cells such as prostate epithelial cells or stromal cells derived from the subject being treated. In some embodiment, the cells may be obtained from biopsies taken from the subject. In some embodiments, malignant prostate tumor cells may be used. In some embodiments, the malignant prostate tumor cells are obtained from tumors excised from the subject being treated. In various embodiments, the cells (e.g., cells obtained from the subject being treated either through biopsies or tumor excision) are transduced with the viral vectors using methods known in the art. In some embodiments, the cells are expanded ex vivo before and/or after viral transduction. In some embodiments, the cells are irradiated before, during, or after viral transduction. In some embodiments, the cells are administered to the subject in the form of, for example, a cell-based vaccine. Additional exemplary cells that may be utilized in methods of the invention include, but are not limited to, cells having low Coxsackie virus and Adenovirus Receptor (CAR) expression and derived from hematopoietic, soft tissue, skin, head and neck, brain, cervical, breast, and esophageal tumors; cells having high CAR expression and derived from bladder, prostate cancer, small intestine, thyroid, testicular, and colon tumors; and cells having a mid-range CAR expression and derived from lung, ovary, stomach, kidney, melanoma, liver, endocrine, and mesothelioma tumors,

In various embodiments, the method may be used to prevent and/or treat prostate cancer by using intracellular or intratumoral injections resulting in autocrine activation of TLR signaling of infected cells or the tumor microenvironment with minimal systemic effect and thereby enabling innate immune response specific to the infected cells or to the tumor microenvironment. In various embodiments, methods of the invention provides continous local TLR5 signaling, for example, in prostate cancer cells and/or prostate tissues. In some embodiments, methods of the invention does not induce systemic TLR5 signaling. In various embodiments, methods of the invention induce local accumulation of mononuclear/lymphoid cells in the prostate for mounting an anti-tumor response and/or suppressing tumor growth and progression. In some embodiments, natural killer (NK) cells and/or neutrophils are recruited to the prostate. In various embodiments, methods of the invention results in activation of TLR signaling (e.g., TLR5 signaling) that are resistant to neutralization by anti-flagellin neutralizing antibodies.

In various embodiments, administration of the agents or cells of the invention results in activation of NF-κΒ. In some embodiments, administration of the agents or cells of the invention results in long term activation of NF- Β in prostate tissues. In some embodiments, the activation of NF-κΒ is restricted to local area of the prostate. In various embodiments, administration of the agents or cells of the invention induces expression of genes involved in immune responses, including but not limited to any of the genes disclosed herein such as CXCL1, IL1 B, S100A9, CCL7, CCL9, CXCL9, CXCL13, CXCL17, IKBKE, NFKBIZ, NLRC5, OASL1 , NLRC5, and CLEC4A1.

In various embodiments, methods of the invention prevent and/or treat prostate cancer and/or any proliferative disorder characterized by abnormal cell growth that originates in the prostate gland. In an embodiment, the methods of the invention prevent pre-cancerous changes in the prostate including the formation and progression of prostatic intraepithelial neoplasia (PIN). PIN may be diagnosed and/or monitored by methods known in the art, such as by prostate biopsy. In an embodiment, the methods of the invention prevent the formation of PIN, for example, in subjects who are at risk of developing prostate cancer. In an embodiment, the methods of the invention prevent the progression of PIN from a low-grade PIN (in which the prostate gland cells look almost normal as determined, for example, under the microscope) into a high-grade PIN (in which the prostate gland cells look abnormal). In an embodiment, the methods of the invention prevent the progression of PIN into prostate cancer in a subject. In some embodiments, the methods of the invention prevent the development of proliferative inflammatory atrophy (PIA) in a subject. In an embodiment, the present invention prevents the progression of proliferative inflammatory atrophy (PIA) into prostate cancer in a subject.

In various embodiments, the methods of the invention prevent and/or treat prostate adenocarcinomas. In an embodiment, the prostate adenocarcinoma may be of epithelial origin. In some embodiments, the prostate tumors being treated can include prostate luminal epithelial cells, prostate basal epithelial cells, stromal cells or a combination of prostate luminal epithelial, prostate basal epithelial cells or stromal cells. In some embodiments, prostate cancer tumors that can be treated comprise CK8+ prostate luminal epithelial cells. In some embodiments, prostate cancer tumors that can be treated may comprise CK5+ prostate basal epithelial cells which are also known as stem/progenital/basal epithelial cells. Other prostate cancers that may be prevented and/or treated include, but are not limited to, prostate small cell carcinoma, prostate squamous cell carcinoma, prostatic sarcoma, prostate transitional cell carcinoma. In an embodiment, methods of the invention prevent and/or treat benign prostatic hyperplasia (BPH), which is characterized as a disease in which prostate epithelial cells grow abnormally and block urine flow. In various embodiments, the prostate cancer prevented and/or treated may be, for example, organ-confined primary prostate cancer, locally invasive advanced prostate cancer, metastatic prostate cancer, castration-resistant prostate cancer or recurrent castration-resistant prostate cancer. Metastatic prostate cancer is characterized by prostate cancer cells that are no longer organ-confined. Recurrent castration-resistant prostate cancer is prostate cancer that does not respond to androgen-deprivation therapy or prostate cancer that recurs after androgen-deprivation therapy.

In various embodiments, the methods of the invention prevent the progression of prostate cancer. Prostate cancer progression may be monitored by methods known in the art, for example, by prostate biopsy. For example, pathologists use the Gleason system to describe the degree of differentiation of prostate cancer cells. The Gleason system uses scores ranging from Grade 2 to Grade 10. Lower Gleason scores describe well-differentiated, less aggressive tumors. Higher scores describe poorly differentiated, more aggressive tumors, In various embodiments, methods of the invention may prevent the progression of prostate cancer form a low grade (e.g., Gleason grade 2) to a higher grade prostate cancer [e.g., Gleason grade 10). In some embodiments, methods of the invention may cause prostate cancer regression, as indicated by, for example, a regression from a higher Gleason grade prostate cancer to a lower Gleason grade prostate cancer. In other embodiments, the staging of the prostate cancer may be determined by the American Joint Committee on Cancer (AJCC) TNM system, which is based on the extent of the main tumor (T category), whether the cancer has spread to nearby lymph nodes (N category), whether the cancer has spread to other parts of the body (M category), the PSA level; and the Gleason score. In the AJCC TNM system, the various factors are combined to determine an overall stage of 1-4. The lower the number (e.g., stage 1), the less the cancer has spread. The higher the number, such as stage 4, means a more advanced cancer. In various embodiments, methods of the invention may prevent prostate cancer progression as monitored by the AJCC TNM system. In various embodiments, methods of the invention may cause prostate cancer regression as monitored by the AJCC TNM system.

In various embodiments, the present invention provides a method of preventing or reducing prostate tumor progression or metastasis in a subject, comprising administering to the subject an effective amount of an agent of the invention. In various embodiments, methods of the invention may be utilized to prevent or reduce tumor metastasis to one or more of lymph nodes, lungs, bones including spinal columns, liver, and/or the brain. In various embodiments, methods of the invention may be utilized to prevent or reduce tumor metastasis to one or more of adrenal glands, breasts, eyes, kidneys, muscles, pancreas, salivary glands, and/or spleen. In some embodiments, methods of the invention prevent or reduce tumor metastasis to the lymph nodes, lungs, spinal column, kidneys, and adrenal glands. In various embodiments, agents of the invention are administered to a subject prior to surgical removal of prostate tumor so as to prevent recurrence or metastasis. As utilized herein, in various embodiments, reducing or preventing prostate tumor progression includes a method of preventing, precluding, delaying, averting, obviating, forestalling, stopping, reducing, or hindering prostate tumor progression in a subject. The disclosed method is considered to reduce prostate tumor progression if there is a reduction or delay in prostate tumor growth, metastasis or one or more symptoms of prostate cancer (e.g., problems urinating, pain during urination, pelvic discomfort, swelling in the legs as a result of edema, blood in urine, swelling of the lymph glands, bone pain) in a subject with a prostate tumor as compared to control subjects with a prostate tumor that did not receive an agent that inhibits proliferation of prostate basal epithelial cells. The disclosed method is also considered to reduce prostate tumor progression if there is a reduction or delay in prostate tumor growth, metastasis or one or more symptoms of prostate cancer {e.g., problems urinating, pain during urination, pelvic discomfort, swelling in the legs as a result of edema, blood in urine, swelling of the lymph glands, bone pain) in a subject with a prostate tumor after receiving an agent of the invention as compared to the subject's progression prior to receiving treatment. Thus, the reduction or delay prostate tumor can be about a 10, 20, 30, 40, 50, 60, 70, 80, 90, 100%, or any amount of reduction in between.

The present invention further provides methods of preventing, precluding, delaying, averting, obviating, forestalling, stopping, reducing, or hindering the onset, incidence or severity of the recurrence of prostate cancer in a subject. As utilized herein, by reappearance of prostate cancer is meant the reappearance of one or more clinical symptoms of prostate cancer after a period devoid of one or more clinical symptoms of prostate cancer. The recurrence of prostate cancer can be after treatment for prostate cancer or after a remission. A recurrence can occur days, weeks, months or years after treatment or after a remission. For example, the disclosed method is considered to reduce the occurrence of prostate cancer if there is a reduction or delay in onset, incidence or severity of the reappearance of prostate cancer, or one or more symptoms of prostate cancer (e.g., problems urinating, pain during urination, pelvic discomfort, swelling in the legs as a result of edema, blood in urine, swelling of the lymph glands, bone pain) in a subject at risk for a recurrence of prostate cancer compared to control subjects at risk for a recurrence of prostate cancer that did not receive the agent of the invention. The disclosed method is also considered to reduce the recurrence of prostate cancer if there is a reduction or delay in onset, incidence or severity of the reappearance of prostate cancer, or one or more symptoms of prostate cancer (e.g., problems urinating, pain during urination, pelvic discomfort, swelling in the legs as a result of edema, blood in urine, swelling of the lymph glands, bone pain) in a subject at risk for recurrence of prostate cancer after receiving an agent of the invention as compared to the subject's progression prior to receiving treatment. A utilized herein, in various embodiments, a subject at risk for recurrence of prostate cancer is a subject that is at risk for the reappearance of prostate cancer after treatment for prostate cancer or after remission from prostate cancer. Treatment methods for prostate cancer include, but are not limited to, orchiectomy (surgical castration), prostatectomy, anti-androgen therapy (for example, Eulexin®, Casodex®, Nilandron® and Nizoral®) radiation therapy, chemotherapy, luteinizing hormone releasing hormone analogs (for example, Lupron®, Viadur®, Eligard®, Zoladex®, Trelstar® and Vantas®), lutenizing hormone releasing hormone antagonists (for example, Plenaxis® and) Firmagon® or combinations of these treatment methods. One of skill in the art can determine if a subject is at risk for recurrence of prostate cancer. For example, after treatment, the subject can be monitored for recurrence of prostate cancer. Routine follow up visits after treatment allow one of skill in the art to determine if the subject is devoid of clinical symptoms or if clinical symptoms of prostate cancer have reappeared. In order to determine the status of the subject, a blood test to measure PSA levels can be performed. The results of the PSA test can indicate that prostate cancer can or has recurred (e.g. PSA levels greater than or equal to about 4 nanograms per milliliter (ng/mL) of blood, e.g. about 4 to about 10, e.g. about 10 or more). Imaging techniques, such as X-rays, RIs, CT scans and bone scans can also be used. Lymph node examinations, biopsies, and digital rectal examinations can also be utilized to identify a subject at risk for recurrence of prostate cancer. These techniques can also be used to stage any recurrence of prostate cancer.

In various embodiments, the methods set forth herein can be utilized to treat prostate cancer or reduce the recurrence of prostate cancer in a subject that is undergoing or who has been treated or who will be treated with one or more prostate cancer treatment modalities. Such treatment modalities include, but are not limited to, orchiectomy (surgical castration), prostatectomy, anti-androgen therapy (for example, Eulexin®, Casodex®, Nilandron® and Nizoral®) radiation therapy, chemotherapy, luteinizing hormone releasing hormone analogs (for example, Lupron®, Viadur®, Eligard®, Zoladex®, Trelstar® and Vantas®), lutenizing hormone releasing hormone antagonists (for example, Plenaxis® and) Firmagon® or combinations of these treatment methods. In an embodiment, methods of the invention are utilized to treat a subject undergoing or who has been or who will be treated with radiation therapy. In an embodiment, methods of the invention are utilized to treat a subject undergoing or who has been or who will be treated with chemotherapy. Examples of chemotherapy involve treatment with chemotherapeutic agents that include, but are not limited to, alkylating agents such as thiotepa and CYTOXAN cyclosphosphamide; alkyl sulfonates such as busulfan, improsulfan and piposulfan; aziridines such as benzodopa, carboquone, meturedopa, and uredopa; ethylenimines and methylamelamines including altretamine, triethylenemelamine, trietylenephosphoramide, triethiylenethiophosphoramide and trimethylolomelamine; acetogenins (e.g., bullatacin and bullatacinone); a camptothecin (including the synthetic analogue topotecan); bryostatin; cally statin; CC-1065 (including its adozelesin, carzelesin and bizelesin synthetic analogues); cryptophycins (e.g., cryptophycin 1 and cryptophycin 8); dolastatin; duocarmycin (including the synthetic analogues, KW-2189 and CB 1-TM1); eleutherobin; pancratistatin; a sarcodictyin; spongistatin; nitrogen mustards such as chlorambucil, chlornaphazine, cholophosphamide, estramustine, ifosfamide, mechlorethamine, mechlorethamine oxide hydrochloride, melphalan, novembichin, phenesterine, prednimustine, trofosfamide, uracil mustard; nitrosureas such as carmustine, chlorozotocin, fotemustine, lomustine, nimustine, and ranimnustine; antibiotics such as the enediyne antibiotics (e.g., calicheamicin, especially calicheamicin gammall and calicheamicin omegall (see, e.g., Agnew, Chem. Intl. Ed. Engl., 33: 183-186 (1994)); dynemicin, including dynemicin A; bisphosphonates, such as clodronate; an esperamicin; as well as neocarzinostatin chromophore and related chromoprotein enediyne antibiotic chromophores), aclacinomysins, actinomycin, authramycin, azaserine, bleomycins, cactinomycin, carabicin, caminomycin, carzinophilin, chromomycinis, dactinomycin, daunorubicin, detorubicin, 6-diazo-5-oxo-L-norleucine, ADRIAMYCIN doxorubicin (including morpholino- doxorubicin, cyanomorpholino-doxorubicin, 2-pyrrolino-doxorubicin and deoxy doxorubicin), epirubicin, esorubicin, idarubicin, marcellomycin, mitomycins such as mitomycin C, mycophenolic acid, nogalamycin, olivomycins, peplomycin, potfiromycin, puromycin, quelamycin, rodorubicin, streptonigrin, streptozocin, tubercidin, ubenimex, zinostatin, zorubicin; anti-metabolites such as methotrexate and 5- fluorouracil (5-FU); folic acid analogues such as denopterin, methotrexate, pteropterin, trimetrexate; purine analogs such as fludarabine, 6-mercaptopurine, thiamiprine, thioguanine; pyrimidine analogs such as ancitabine, azacitidine, 6-azauridine, carmofur, cytarabine, dideoxyuridine, doxifluridine, enocitabine, floxuridine; androgens such as calusterone, dromostanolone propionate, epitiostanol, mepitiostane, testolactone; anti-adrenals such as minoglutethimide, mitotane, trilostane; folic acid replenisher such as frolinic acid; aceglatone; aldophosphamide glycoside; aminolevulinic acid; eniluracil; amsacrine; bestrabucil; bisantrene; edatraxate; demecolcine; diaziquone; elformithine; elliptinium acetate; an epothilone; etoglucid; gallium nitrate; hydroxyurea; lentinan; lonidainine; maytansinoids such as maytansine and ansamitocins; mitoguazone; mitoxantrone; mopidanmol; nitraerine; pentostatin; phenamet; pirarubicin; losoxantrone; podophyllinic acid; 2-ethylhydrazide; procarbazine; PSK polysaccharide complex (JHS Natural Products, Eugene, Oreg.); razoxane; rhizoxin; sizofuran; spirogermanium; tenuazonic acid; triaziquone; 2,2',2"-trichlorotriethylamine; trichothecenes {e.g., T-2 toxin, verracurin A, roridin A and angutdine); urethan; vindesine; dacarbazine; mannomustine; mitobronitol; mitolactol; pipobroman; gacytosine; arabinoside ("Ara-C"); cyclophosphamide; thiotepa; taxoids, e.g., TAXOL paclitaxel (Bristol-Myers Squibb Oncology, Princeton, N.J.), ABRAXANE Cremophor-free, albumin-engineered nanoparticle formulation of paclitaxel (American Pharmaceutical Partners, Schaumberg, 111.), and TAXOTERE doxetaxel (Rhone-Poulenc Rorer, Antony, France); chloranbucil; GEMZAR gemcitabine; 6-thioguanine; mercaptopurine; methotrexate; platinum analogs such as cisplatin, oxaliplatin and carboplatin; vinblastine; platinum; etoposide (VP-16); ifosfamide; mitoxantrone; vincristine; NAVELBINE. vinorelbine; novantrone; teniposide; edatrexate; daunomycin; aminopterin; xeloda; ibandronate; irinotecan (Camptosar, CPT-11) (including the treatment regimen of irinotecan with 5-FU and leucovorin); topoisomerase inhibitor RFS 2000; difluoromethylornithine (DMFO); retinoids such as retinoic acid; capecitabine; combretastatin; leucovorin (LV); oxaliplatin, including the oxaliplatin treatment regimen (FOLFOX); lapatinib (Tykerb); inhibitors of P C-α, Raf, H-Ras, EGFR (e.g., erlotinib (Tarceva)) and VEGF-A that reduce cell proliferation and pharmaceutically acceptable salts, acids or derivatives of any of the above. In various embodiments, administration of the agents of the invention in combination with radiation therapy and/or chemotherapy prevents or reduces prostate tumor metastasis to one or more metastatic sites described herein. In an embodiment, methods of the invention are utilized to treat a subject undergoing or who has been or who will be treated with one or more immune-modulating agents, for example, without limitation, agents that modulate immune checkpoint. In various embodiments, the immune-modulating agent targets one or more of PD-1 , PD-L1, and PD-L2. In various embodiments, the immune-modulating agent is PD-1 inhibitor. In various embodiments, the immune- modulating agent is an antibody specific for one or more of PD-1, PD-L1, and PD-L2. For instance, in some embodiments, the immune-modulating agent is an antibody such as, by way of non-limitation, nivolumab, (ONO- 4538/BMS-936558, MDX1106, OPDIVO, BRISTOL MYERS SQUIBB), pembrolizumab (KEYTRUDA, MERCK), pidilizumab (CT-011, CURE TECH), MK-3475 (MERCK), BMS 936559 (BRISTOL MYERS SQUIBB), MPDL3280A (ROCHE), atezolizumab (TECENTRIQ, ROCHE), and durvalumab (MEDI4736). In some embodiments, the immune-modulating agent targets one or more of CD137 or CD137L In various embodiments, the immune- modulating agent is an antibody specific for one or more of CD137 or CD137L. For instance, in some embodiments, the immune-modulating agent is an antibody such as, by way of non-limitation, urelumab (also known as BMS- 663513 and anti-4-1 BB antibody). In some embodiments, the immune-modulating agent is urelumab (optionally with one or more of nivolumab, lirilumab, and urelumab). In some embodiments, the immune-modulating agent is an agent that targets one or more of CTLA-4, AP2M1 , CD80, CD86, SHP-2, and PPP2R5A. In various embodiments, the immune-modulating agent is an antibody specific for one or more of CTLA-4, AP2M1, CD80, CD86, SHP-2, and PPP2R5A. For instance, in some embodiments, the immune-modulating agent is an antibody such as, by way of non-limitation, ipilimumab (MDX-010, MDX-101, Yervoy, BMS) and/or tremelimumab (Pfizer). In some embodiments, the immune-modulating agent is ipilimumab (optionally with bavituximab). In various embodiments, the immune- modulating agent targets CD20. In various embodiments, the immune-modulating agent is an antibody specific CD20. For instance, in some embodiments, the immune-modulating agent is an antibody such as, by way of non- limitation, Ofatumumab (GENMAB), obinutuzumab (GAZYVA), AME-133v (APPLIED MOLECULAR EVOLUTION), Ocrelizumab (GENENTECH), TRU-015 (TRUBION/EMERGENT), veltuzumab (IMMU-106).

In various embodiments, administration of the agents of the invention in combination with one or more immune- modulating agents prevents and/or reduces prostate tumor metastasis to one or more metastatic sites described herein. For example, combination treatment with immune-modulating agents such as PD-1 or PD-L1 inhibitors (e.g., OPDIVO, KEYTRUDA, TECENTRIQ, or durvalumab) may prevent metastasis to the lungs. In another example, combination treatment with immune-modulating agents such as CTLA-4 antibodies (e.g., YERVOY) may prevent metastasis to the brain. In some embodiments, methods of the invention are utilized to treat a subject undergoing or who has been or who will be treated with one or more vaccinations or other immunotherapeutic treatments including, but not limited to, Sipuleucel-T, an autologous cellular vaccine consisting of activated antigen-presenting cells loaded with prostatic acid phosphatase (PAP); PROSTVAC^®-VF, a poxvirus-based vaccine engineered to present prostate-specific antigen (PSA) and three immune costimulatory molecules; GVAX, a vaccine consisting of two prostate cancer cell lines engineered to secrete granulocyte-macrophage colony stimulating factor (G -CSF); and Ipilimumab, an antibody against cytotoxic T-lymphocyte associated antigen-4.

In some embodiments, methods of the invention provide a more effective cell-based vaccine against prostate cancer than other vaccinations or immunotherapeutic treatments against prostate cancer, including, but not limited to, Sipuleucel-T, BPX-101, DCVAC/Pa, PROSTVAC®-VF, and GVAX.

In various embodiments, the methods of the invention are utilized to prevent and/or treat prostate cancer in a subject in need thereof. In various embodiments, the subject is at risk for prostate cancer. In an embodiment, the subject may have a family history of prostate cancer. In some embodiments, the subject may harbor genetic abnormalities that predispose the subject to developing prostate cancer. For example, the subject may harbor mutations in BRCA1 and/or BRCA2. In some embodiments, the subject is obese.

In various embodiments, methods of the invention are provided as alternative treatments to subjects who want to avoid the side-effects associated with traditional prostate cancer treatments such as radiation, chemotherapy, or surgery. In some embodiments, the methods of the invention may be utilized by subjects to avoid side effects including, but not limited to, incontinence, impotence, and loss of fertility.

Kits

The invention also provides kits for the administration of any agent (e.g., an adenoviral vector or a cell transduced with the adenoviral vector) as described herein. The kit is an assemblage of materials or components, including at least one of the inventive pharmaceutical compositions described herein. Thus, in some embodiments, the kit contains at least one of the pharmaceutical compositions described herein.

The exact nature of the components configured in the kit depends on its intended purpose. In one embodiment, the kit is configured for the purpose of treating human subjects.

Instructions for use may be included in the kit. Instructions for use typically include a tangible expression describing the technique to be employed in using the components of the kit to effect a desired outcome, such as to treat prostate cancer. Optionally, the kit also contains other useful components, such as, diluents, buffers, pharmaceutically acceptable carriers, syringes, catheters, applicators, pipetting or measuring tools, bandaging materials or other useful paraphernalia as will be readily recognized by those of skill in the art.

The materials and components assembled in the kit can be provided to the practitioner stored in any convenience and suitable ways that preserve their operability and utility. For example, the components can be provided at room, refrigerated or frozen temperatures. The components are typically contained in suitable packaging materials. In various embodiments, the packaging material is constructed by well-known methods, preferably to provide a sterile, contaminant-free environment. The packaging material may have an external label which indicates the contents and/or purpose of the kit and/or its components. Definitions

As used herein, "a," "an," or "the" can mean one or more than one.

Further, the term "about" when used in connection with a referenced numeric indication means the referenced numeric indication plus or minus up to 10% of that referenced numeric indication. For example, the language "about 50" covers the range of 45 to 55. An "effective amount," when used in connection with medical uses is an amount that is effective for providing a measurable treatment, prevention, or reduction in the rate of pathogenesis of a disease of interest.

As used herein, something is "decreased" if a read-out of activity and/or effect is reduced by a significant amount, such as by at least about 10%, at least about 20%, at least about 30%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90%, at least about 95%, at least about 97%, at least about 98%, or more, up to and including at least about 100%, in the presence of an agent or stimulus relative to the absence of such modulation. As will be understood by one of ordinary skill in the art, in some embodiments, activity is decreased and some downstream read-outs will decrease but others can increase.

Conversely, activity is "increased" if a read-out of activity and/or effect is increased by a significant amount, for example by at least about 10%, at least about 20%, at least about 30%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90%, at least about 95%, at least about 97%, at least about 98%, or more, up to and including at least about 100% or more, at least about 2-fold, at least about 3- fold, at least about 4-fold, at least about 5-fold, at least about 6-fold, at least about 7-fold, at least about 8-fold, at least about 9-fold, at least about 10-fold, at least about 50-fold, at least about 100-fold, in the presence of an agent or stimulus, relative to the absence of such agent or stimulus. As referred to herein, all compositional percentages are by weight of the total composition, unless otherwise specified. As used herein, the word "include," and its variants, is intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that may also be useful in the compositions and methods of this technology. Similarly, the terms "can" and "may" and their variants are intended to be non-limiting, such that recitation that an embodiment can or may comprise certain elements or features does not exclude other embodiments of the present technology that do not contain those elements or features. Although the open-ended term "comprising," as a synonym of terms such as including, containing, or having, is used herein to describe and claim the invention, the present invention, or embodiments thereof, may alternatively be described using alternative terms such as "consisting of or "consisting essentially of."

As used herein, the words "preferred" and "preferably" refer to embodiments of the technology that afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the technology.

The amount of compositions described herein needed for achieving a therapeutic effect may be determined empirically in accordance with conventional procedures for the particular purpose. Generally, for administering therapeutic agents for therapeutic purposes, the therapeutic agents are given at a pharmacologically effective dose. A "pharmacologically effective amount," "pharmacologically effective dose," "therapeutically effective amount," or "effective amount" refers to an amount sufficient to produce the desired physiological effect or amount capable of achieving the desired result, particularly for treating the disorder or disease. An effective amount as used herein would include an amount sufficient to, for example, delay the development of a symptom of the disorder or disease, alter the course of a symptom of the disorder or disease (e.g., slow the progression of a symptom of the disease), reduce or eliminate one or more symptoms or manifestations of the disorder or disease, and reverse a symptom of a disorder or disease. Therapeutic benefit also includes halting or slowing the progression of the underlying disease or disorder, regardless of whether improvement is realized.

Effective amounts, toxicity, and therapeutic efficacy can be determined by standard pharmaceutical procedures in cell cultures or experimental animals, e.g., for determining the LD50 (the dose lethal to about 50% of the population) and the ED50 (the dose therapeutically effective in about 50% of the population). The dosage can vary depending upon the dosage form employed and the route of administration utilized. The dose ratio between toxic and therapeutic effects is the therapeutic index and can be expressed as the ratio LD50/ED50. In some embodiments, compositions and methods that exhibit large therapeutic indices are preferred. A therapeutically effective dose can be estimated initially from in vitro assays, including, for example, cell culture assays. Also, a dose can be formulated in animal models to achieve a circulating plasma concentration range that includes the IC50 as determined in cell culture, or in an appropriate animal model. Levels of the described compositions in plasma can be measured, for example, by high performance liquid chromatography. The effects of any particular dosage can be monitored by a suitable bioassay. The dosage can be determined by a physician and adjusted, as necessary, to suit observed effects of the treatment.

In certain embodiments, the effect will result in a quantifiable change of at least about 10%, at least about 20%, at least about 30%, at least about 50%, at least about 70%, or at least about 90%. In some embodiments, the effect will result in a quantifiable change of about 10%, about 20%, about 30%, about 50%, about 70%, or even about 90% or more. Therapeutic benefit also includes halting or slowing the progression of the underlying disease or disorder, regardless of whether improvement is realized.

As used herein, "methods of treatment" are equally applicable to use of a composition for treating the diseases or disorders described herein and/or compositions for use and/or uses in the manufacture of a medicaments for treating the diseases or disorders described herein. This invention is further illustrated by the following non-limiting examples.

EXAMPLES

Example 1: Synthesis of Bi-Cistonic Expression TLR5/Flaoellin Vector and Treatment of Tumor Cells

Vector constructs were created for expressing Toll-like receptor 5 (TLR-5) and flagellin CBLB502 as described in U.S. Patent No. 9,205,095 and WO 2015/080631 , the entire contents of which are hereby incorporated by reference. Specifically, Mobilan M-0 was a non-replicating adenovirus carrying a bi-cistronic expression cassette that directs constitutive expression of full-length human TLR5 from the CMV promoter and a secreted version of the flagellin- based TLR5 agonist entolimod (CBLB502s) from the EF1 promoter (Figure 1, panel a). Western blotting confirmed production of both hTLR5 and CBLB502 proteins by Μ-0-infected TLR5-negative MOSEC murine ovarian cancer cells. However, CBLB502s produced in these cells had a larger apparent size on the blots than expected and its specific activity (ratio of CBLB502s amount measured by ELISA and its NF-KB-activating capacity in HEK293-NF-KB- lacZ reporter cells) was only -1% of that observed for CBLB502 produced in £ coli. The presence of four predicted glycosylation sites in the amino acid sequence of CBLB502 suggested that CBLB502s produced in mammalian cells might be inactive due to glycosylation. Indeed, treatment of lysates of Μ-0-infected MOSEC cells with de- glycosylating enzymes resulted in a shift in the mobility of CBLB502s to the expected size. Accordingly, a "non- glycosylated" mutant version of CBLB502 (CBLB502NQ) containing arginine to glutamine substitutions in all four predicted glycosylation sites was produced in E. coli and found to have similar specific activity in HEK293-NF-KB-lacZ reporter cells than CBLB502. Based on these findings, a new bi-cistronic adenoviral construct (named Mobilan M- VM3) was generated to direct expression of CBLB502NQs from the UbiC promoter along with CMV promoter- controlled hTLR5 (Figure 1, panel b).

Example 2: Prophylactic anti-tumor activity of an adenovirus co-expressing TLR5 and an unalvcosylated secreted flagellin variant

The objective of this study was to determine the prophylactic efficacy of an antitumor vaccination by irradiated M- VM3-infected prostate tumor cells. As described elsewhere, M-VM3 was an adenovirus encoding TLR5 and an unglycosylated secreted flagellin variant. The study was conducted using the mouse prostate tumor TRAMP-C2 cell line that could grow in vitro as well as a subcutaneous tumor in syngeneic C57BL/6 mice. This syngeneic model allowed evaluation of M-VM3-induced antitumor responses in immunocompetent mice.

Experimental Protocol

Forty males C57BL/6 mice (8 weeks old) were purchased from Taconic, Inc. (Germantown, NY, USA). The mice were housed≤5 per cage. Identification of animals within each cage was done by ear punch. Mice were randomly assigned to treatment groups. Animals were provided a commercial rodent diet (5% 7012 Teklad LM-485 Mouse/Rat Sterilizable Diet, Harlan) and sterile drinking water. They had corn cab bedding. All the animals were confined to a limited access facility with environmentally-controlled housing conditions throughout the entire study period and maintained at 18-26°C, 30-70% air humidity, 12-hour light-dark cycle (light on at 6:00 and off at 18:00). The animals were acclimatized in the housing conditions for a minimum of 3-5 days before the start of the experiment.

The mouse prostate tumor cell line TRAMP-C2 (a clone originating from spontaneous TRAMP tumor) was used. The TRAMP-C2 cells were grown in Dulbecco's modified Eagle's medium (DMEM) supplemented with 10% fetal bovine serum, 100 mg/ml streptomycin, 100 lU/ml penicillin, 5pg/ml insulin and 1CH³ M dihydrotestosterone.

The M-VM3 adenovirus is as described previously. The concentration of the M-VM3 adenovirus stock was 1.1x10¹² vp/ml, stored at -80°C. The Ad-mCherry adenovirus was used as control. Specifically, this was an adenovirus expressing red fluorescent protein (mCherry) under the control of a CMV promoter. The concentration of the Ad- mCherry adenovirus stock was 1x10¹² vp/ml, stored at -80°C.

A cell-based vaccine was generated including lethally irradiated (50 Gy dose) TRAMP-C2 cells that were infected with M-VM3. Specifically, 70% confluent TRAMP-C2 cells were infected with M-VM3 (MOI=1.2x10^s) and gamma irradiated with a dose of 50 Gy at 48-hours after infection. For infection of TRAMP-C2 cells, the M-VM3 viral stock (at 1.1x10¹² vp/ml) was diluted with adenoviral buffer (20 mM Tris-HCI, 25 mM NaCI, 2.5% glycerol) to a final concentration of 2x10¹⁰ vp/ml. The control Ad-mCherry viral stock (at 1x10¹² vp/ml) was diluted 50-fold with adenoviral buffer to a final concentration of 2x10¹⁰ vp/ml.

For mice vaccination, C57BL/6 mice (n=10 per group) were vaccinated subcutaneously (s.c.) with M-VM3- (MOI=1.2x10⁵) infected TRAMP-C2 cells that were irradiated 48 hours after virus infection. As a control, similarly prepared TRAMP-C2 cells were used that were either infected with Ad-mCherry (MOI=1.2x10⁵) or uninfected. A fourth group of mice was not vaccinated. Mice were vaccinated using a prime plus two boost strategy (on days 0, 14, 21).

Vaccinated mice were subsequently challenged with un-infected TRAMP-C2 prostate tumor cells. Immediately before inoculation, not-infected TRAMP-C2 prostate tumor cells (80% confluent cultures) were removed from plates by trypsinization, centrifuged, and washed once in PBS. TRAMP-C2 cells were resuspended in PBS at a concentration of 5x10⁷ cells/ml. Mice were anesthetized with isoflurane and given a single s.c. injection of 200 μΙ cell suspension (delivering 1x10⁷ cells/per mouse) on the right side of the abdomen (shaved area) 14 days after the last vaccination (i.e., on study day 35). Percent of mice that did not develop tumors (tumor-free mice) after tumor challenge (38 days) was determined and compared between all treatment groups. Subcutaneous tumor growth was monitored until mouse death or tumors reached the endpoint size requiring euthanasia (2,000 mm³). The study design is provided below in Table 1.

Table 1 - Study Design

Animals were monitored daily for survival and signs of morbidity. Tumor growth was monitored by measuring the tumor twice per week. Tumors were measured by digital caliper in two dimensions (perpendicular to each other) and the obtained measurements were used to calculate tumor volume assuming a prolate spheroid tumor mass. The tumor size endpoint was set at a volume of 2,000 mm³. Animals were euthanized when tumors reached the endpoint size. Mice that survived to the end of the study were euthanized by C0₂ overdose followed by cervical dislocation. The study was terminated on Day 38 post-tumor challenging. In addition, mice were euthanized by the same method when their tumor reached the size endpoint or if significant signs of morbidity were observed.

Mean tumor volume was compared between study groups using Student's t test (2-tailed, non-paired with unequal variance) as implement in Microsoft Excel 2010. P values≤ 0.05 were considered statistically significant. Experimental Results

Data on tumor growth after immunization and tumor challenge (38 days) are provided in Table 2 below. Also see Figure 2. Table 2 - Raw Data For Individual Mice, Tumor Volumes Post Immunization

Sac'd = Sacrificed Vaccination of mice with -VM3-infected (MOI=1.2x10⁵) cells (1x10⁶) using a prime plus two boost strategy (on days 0, 14, 21) had beneficial antitumor effect on prostate tumor growth compared to group of mice which were not vaccinated, vaccinated with uninfected cells or vaccinated with a control virus Ad-mCherry-infected cells. This was illustrated by lower percentage of mice that developed s.c. tumors in 38 days in the group immunized with -VM3- infected cells. As shown in Figure 1, the percentage of tumor-free mice was significantly higher in mice which were immunized with cells infected with M-VM3 (70%) compared to groups of mice which were not vaccinated (10%), vaccinated with uninfected cells or vaccinated with Ad-mCherry-infected cells (30%). This effect was statistically significant (P = 0.02 for difference between mouse group immunized with M-VM3 and uninfected cells according to Fisher's exact test).

Altogether, these data indicated that a cell-based vaccination using M-VM3 infected cells effectively prevented tumor development.

Example 3. Anti-metastatic activity of an adenovirus co-expressing TLR5 and an unalvcosylated secreted flagellin variant The objective of this study was to test M-VM3 for anti-metastatic activity in a TRAMP-C2 prostate tumor model in which animal mortality was linked to development of tumor metastases after surgical removal of subcutaneously- growing tumors. TRAMP-C2 cells can grow as subcutaneous tumor in syngeneic C57BL/6 mice which allowed evaluation of M-VM3-induced anti-metastatic effect in immunocompetent mice.

Experimental Protocol A syngeneic mouse TRAMP-C2 prostate tumor model was used which involved TRAMP-C2 prostate cancer cells growing in C57BL/6 male mice (30 mice).

Specifically, thirty male C57BL/6 mice (8 weeks old) were purchased from Taconic, Inc. (Germantown, NY, USA). The mice were housed≤5 per cage. Identification of animals within each cage was done by ear punch. Mice were randomly assigned to treatment groups. Animals were provided a commercial rodent diet (5% 7012 Teklad LM-485 Mouse/Rat Sterilizable Diet, Harlan) and sterile drinking water. They had corn cab bedding. All of the animals were confined to a limited access facility with environmentally-controlled housing conditions throughout the entire study period and maintained at 18-26°C, 30-70% air humidity, 2-hour light-dark cycle (light on at 6:00 and off at 18:00). The animals were acclimatized in the housing conditions for a minimum of 3-5 days before the start of the experiment. Immediately before inoculation, TRAMP-C2 tumor cells (80% confluent cultures) were removed from plates by trypsinization, centrifuged, and washed once in PBS. The cells were resuspended in PBS at a concentration of 5x10⁷ cells/ml. The tumor cells (1x10⁷ cells per mouse) were s.c. injected into the flank of C57BL/6 mice to establish subcutaneous tumors. In particular, mice were anesthetized with isoflurane and given a single subcutaneous (s.c.) injection of 200 μΙ cell suspension (delivering 1x10⁷ cells) on the right side of the abdomen (shaved area).

Tumor-bearing mice were treated when tumors became palpable (100 mm³ in volume). This was approximately 4 weeks after tumor cell inoculation. TRAMP-C2 tumor-bearing mice were treated with control vehicle (adenoviral ^■ buffer, Group 1), Ad-mCherry (10⁸ vp, Group 2) or M-VM3 virus (10⁸ vp, Group 3). All treatments included a single intratumoral injection into the center of the tumor. Injections were performed using a 27-gauge needle on isoflurane- anesthetized mice under aseptic conditions with an injection volume of 50 μΙ per tumor.

Tumors were surgically removed 7 days after injection. Surgery was performed aseptically in a biological safety cabinet. Mice were anesthetized with isoflurane during the procedure. Buprenorphine at a concentration of 0.1 mg/kg (100 μΙ_) for analgesia and saline (500 μί.) for rehydration were given s.c. The area was shaved and scrubbed with betadine followed by 70% isopropyl alcohol. An incision was made in the skin using sterile scissors. Tumors were excised away from surrounding skin and muscle using blunt dissection. Tumors were removed and the skin was closed using wound clips. Mice were kept warm and monitored until they were awake. Mice were monitored post- surgery and daily afterwards. Wound clips were removed when the skin has healed, 7-10 days post-surgery.

The study design and experimental groups are provided below in Table 3.

Table 1. Study Design

Animals were monitored daily for survival and signs of morbidity. Tumor growth was monitored by measuring the tumor twice per week. Tumors were measured by digital caliper in two dimensions (perpendicular to each other) and the obtained measurements were used to calculate tumor volume assuming a prolate spheroid tumor mass. The tumor size endpoint was set at a volume of 2,000 mm³. Animals were euthanized when tumors reached the endpoint size. Mice that survived to the end of the study were euthanized by CO2 overdose followed by cervical dislocation. The study was terminated on Day 150 post-surgical removal of tumors. In addition, mice were euthanized by the same method when their tumor reached the size endpoint (see Section 4.4.10) or if significant signs of morbidity were observed. Mean tumor volume was compared between study groups using Student's t test function in Microsoft Excel 2010. P values≤ 0.05 were considered statistically significant

Experimental Results

Survival data for TRA P-C2-bearing C57BL/6 mice with tumors treated with different adenoviruses: Ad-mCherry (1x10⁸ vp) or M-VM3 (1x10⁸ vp) or with vehicle (PBS) and then surgically removed are provided in Table 4 below. Also see Figure 3.

Table 2. Mouse Survival Data For Intratumoraly Immunized Groups Of Mice

Treatment of mice bearing subcutaneous tumors formed by the TRAMP-C2 prostate cancer cell line with a single intratumoral injection of M-VM3 (1x10⁸ vp) increased survival of mice after surgical removal of tumors compared with the injection of Ad-mCherry (1x10⁸ vp) and PBS. Specifically, 70% of mice that received intratumoral delivery of M- VM3 prior to the tumor removal survived to the end of the study on Day 150. In contrast, only 30% of mice in the PBS-treated group and 50% of the mice in the Ad-mCherry-treated group survived to the study end (P = 0.06 for the difference between M-VM3 and control groups of mice on day 150 by log-rank test).

Altogether, these data strongly suggest that M-VM3 can be effectively used as a treatment to prevent prostate tumor metastasis prior to surgical removal of the primary prostate tumors.

Example 4. Additional functional characterization of an adenovirus co-expressing TLR5 and an unalvcosylated secreted flagellin variant

Additional functional characterization of M-VM3 is provided in Appendix A provided herewith. The figure numbers provided in Appendix A are independent from the figure numbers presented elsewhere herein. EQUIVALENTS

While the invention has been described in connection with specific embodiments thereof, it will be understood that it is capable of further modifications and this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth and as follows in the scope of the appended claims.

Those skilled in the art will recognize, or be able to ascertain, using no more than routine experimentation, numerous equivalents to the specific embodiments described specifically herein. Such equivalents are intended to be encompassed in the scope of the following claims. INCORPORATION BY REFERENCE

All patents and publications referenced herein are hereby incorporated by reference in their entireties.

The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such publication by virtue of prior invention. As used herein, all headings are simply for organization and are not intended to limit the disclosure in any manner. The content of any individual section may be equally applicable to all sections.

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26. Hurwitz AA, Foster BA, Kwon ED, Truong T, Choi EM, Greenberg NM et al. Combination immunotherapy of primary prostate cancer in a transgenic mouse model using CTLA-4 blockade. Cancer research 2000; 60: 2444- 2448.

27. Mentor-Marcel R, Lamartiniere CA, Eltoum IE, Greenberg NM, Elgavish A. Genistein in the diet reduces the incidence of poorly differentiated prostatic adenocarcinoma in transgenic mice (TRAMP). Cancer research 2001 ; 61: 6777-6782.

28. Michael A, Ball G, Quatan N, Wushishi F, Russell N, Whelan J et al. Delayed disease progression after allogeneic cell vaccination in hormone-resistant prostate cancer and correlation with immunologic variables. Clinical cancer research : an official journal of the American Association for Cancer Research 2005; 11: 4469-4478.

29. Komnan AJ, Peggs KS, Allison JP. Checkpoint blockade in cancer immunotherapy. Advances in immunology 2006; 90: 297-339.

30. Bramson JL, Hitt M, Addison CL, Muller WJ, Gauldie J, Graham FL. Direct intratumoral injection of an adenovirus expressing interleukin-12 induces regression and long-lasting immunity that is associated with highly localized expression of interleukin-12. Hum Gene Ther 1996; 7: 1995-2002.

APPENDIX A

Introduction

TLR5 agonists are promising anti-cancer agents due to their safety as well as their efficacy. Unlike many other TLRs, TLR5 signaling, while immunostimulatory, does not induce certain highly pro-inflammatory cytokines that can cause a self-amplifying and potentially dangerous "cytokine storm".^17"19 The safety of TLR5 agonists is supported by the results of two clinical studies in which >150 healthy subjects were administered the flagellin derivative entolimod (previously CBLB502), which is being developed by Cleveland BioLabs Inc. (CBLI) for tissue protective and anticancer applications.

Anti-tumor/metastatic efficacy of TLR5 agonists is correlated with the level of TLR5 expression by the tumor itself ³· · ⁶ or in the tissue to which the tumor metastasizes.⁸ Here a strategy was introduced to increase the range of tumors that might be effectively treated via TLR5 agonist-dependent immunotherapy. An adenovirus-based construct (Mobilan M-VM3) was generated to direct co-expression of TLR5 and a secreted variant of entolimod with the expectation that delivery of the construct to a tumor would establish potent autocrine/paracrine TLR5 activation regardless of the tumor's natural TLR5 expression status. Without wishing to be bound by theory, it is believed that Mobilan-driven TLR5 signaling within a tumor would stimulate innate immune responses capable of suppressing primary tumor growth and also providing long-term protection against metastases and recurrent tumors.

To test this approach, prostate cancer was targeted after finding that most prostate cancers express the Coxsackie virus and Adenovirus Receptor (CAR)²⁰ required for efficient infection by serotype 5 adenovirus-based vectors such as Mobilan. Prostate cancer is extremely common, with a 14% lifetime risk of diagnosis for American men, and remains the second leading cause of cancer death in this demographic group.²¹ Therefore, development of new, more effective treatments for prostate cancer is critical.

While other immunofherapeutic approaches against prostate cancer, including, cell-based vaccines (Sipuleucel-T, BPX-101 , DCVAC/Pa GVAX)^{21 26}, virus-based vaccines (PROSTVAC®-VF)²^ ²⁸ and antibodies against immune checkpoint proteins (CTLA-4, PD1/PD-L1),²⁹-³⁶ have shown some efficacy, none of these strategies were found to extend survival for more than a few months.

For the studies with Mobilan M-VM3, the well-known TRAMP (transgenic adenocarcinoma of the mouse prostate) model was used, which closely mimics the pathogenesis of the human disease³⁷-³⁹ and has been widely adopted to evaluate candidate therapies.⁴⁰-⁴² In this model, expression of the large and small SV40 tumor antigens from the prostate-specific rat probasin promoter leads to spontaneous development of epithelial hyperplasia in the prostate by 8 weeks of age and then to malignant adenocarcinomas^. Infection of TRAMP prostate tumor cells with M-VM3 established expression of both TLR5 and secreted entolimod as expected and induced activation of NF-κΒ in vitro and in vivo. Intra-prostate tumor injections of M-VM3 in TRAMP mice led to strong induction of inflammatory genes, mobilization of innate immune cells into tumors, and signs of tumor atrophy. Further support for use of Mobilan against prostate cancer was provided by results showing that intratumoral (i.t.) injection of M-VM3 into s.c. prostate tumors improved animal survival after surgical resection of the tumors (i.e., suppressed tumor metastasis) and that vaccination of mice with irradiated M-VM3-infected prostate tumor cells protected mice against tumor challenge. Results

Generation and characterization of Mobilan constructs

Mobilan M-0 is a non-replicating adenovirus carrying a bi-cistronic expression cassette that directs constitutive expression of full-length human TLR5 from the CMV promoter and a secreted version of the flagellin-based TLR5 agonist entolimod⁴³ (CBLB502s) from the EF1 promoter (Fig. 1A(a)). Western blotting confirmed production of both hTLR5 and CBLB502 proteins by M-O-infected TLR5-negative MOSEC murine ovarian cancer cells (Fig. 1B). However, CBLB502s produced in these cells had a larger apparent size on the blots than expected and its specific activity (ratio of CBLB502s amount measured by ELISA and its NF-KB-activating capacity in HEK293-NF- B-lacZ reporter cells) was only -1% of that observed for CBLB502 produced in E. coli. The presence of four predicted glycosylation sites in the amino acid sequence of CBLB502 suggested that CBLB502s produced in mammalian cells might be inactive due to glycosylation. Indeed, treatment of lysates of M-O-infected MOSEC cells with de- glycosylating enzymes resulted in a shift in the mobility of CBLB502s to the expected size (Fig. 1 B(b)). A "non- glycosylated" mutant version of CBLB502 (CBLB502NQ) containing arginine to glutamine substitutions in all four predicted glycosylation sites was produced in E. coli and found to have similar specific activity in HEK293-NF-KB-lacZ reporter cells than CBLB502 (Fig. 1C). Based on these findings, a new bi-cistronic adenoviral construct (named Mobilan M-VM3) was generated to direct expression of CBLB502NQ.S from the UbiC promoter along with CMV promoter-controlled hTLR5 (Fig. 1A(b)). The specific activity of CBLB502NQs produced in M-VM3-infected MOSEC cells was slightly lower than that of the £.co//-produced CBLB502 (Fig. 1 E); this was likely due to partial degradation of CBLB502NQs during expression (Fig. 1D).

Establishment of fully functional autocrine/paracrine TLR5 signaling by M-VM3 was demonstrated in TLR5-negative MOSEC cells (non-responsive to entolimod, Fig. S2, A-C) using nuclear translocation of the p65 subunit of NF-κΒ as a readout of its activation (Fig. 2A-B). M-VM3 infection also led to p65 nuclear localization in hepatocyte cultures from TLR5KO mice (Fig. S2, D-l). Finally, since this study became focused on prostate cancer (see below), the functionality of M-VM3 was tested in the TRAMP-C2 prostate cancer cell line established from a primary TRAMP mouse prostate tumor.³⁷ TRAMP-C2 cells were stably transfected with an NF-κΒ reporter construct and then infected with M-VM3 or a control adenovirus directing CMV promoter-driven red fluorescent protein expression (Ad-mCherry), Dose-dependent NF-κΒ activation was observed in the M-VM3-infected TRAMP-C2 cells (Fig. 2C). One potential limitation for clinical use of TLR5 agonists is pre-existence of a prohibitively high level of anti-flagellin neutralizing antibodies in -10% of humans (CBLI, unpublished), likely due to exposure to flagellated enterobacteria of the gut microflora. However, it was determined that anti-flagellin neutralizing antibodies did not significantly affect M-VM3-directed TLR5 signaling in OSEC-NF-KB-luciferase reporter cells (Fig. 1F) even with antibody levels 10-fold higher than that required to neutralize CBLB502NQs added to the medium of TLR5-positive HEK293-NF-icB-lacZ reporter cells (Fig. S1). Without wishing to be bound by theory, it is believed that in M-VM3-infected cells TLR5 interacts with CBLB502NQs during co-secretion and the complex is either inaccessible to or cannot be disrupted by neutralizing antibodies. Resistance of M-VM3-induced TLR5 signaling to neutralizing antibodies would allow its therapeutic use in a wider human population compared to entolimod.

Selection of tumor type for Mobilan treatment

Membrane expression of the Coxsackie virus and Adenovirus Receptor (CAR) is required for efficient infection of cells by adenovirus serotype 5 and its derivatives such as M-VM3. To identify tumor types potentially treatable by M- VM3, human tissue microarrays (TMA) from the Roswell Park Cancer Institute (RPCI) Pathology Core were stained with anti-CAR antibodies. Initial staining of a TMA containing 252 samples (Fig. S3) representing 23 different tumor types and 12 different normal tissues divided tumor types into three categories: (i) low CAR expression (hematopoietic, soft tissue, skin, head and neck, brain, cervical, breast, and esophageal tumors); (ii) high CAR expression (bladder, prostate cancer, small intestine, thyroid, testicular, and colon tumors); and (iii) mid-range CAR expression (lung, ovary, stomach, kidney, melanoma, liver, endocrine, and mesothelioma tumors). Subsequent anti- CAR staining of a TMA with 134 prostate tumor samples, 134 normal prostate samples and 68 samples of other normal tissues demonstrated that 121 (90%) of prostate tumors (as well as normal prostate tissues) were CAR- positive (Fig. 3A). This suggests that M-VM3 treatment could be effective in the vast majority of prostate cancer patients. Strong CAR expression was also detected in TRAMP-C2 murine prostate cancer cells (Fig. 3B).

To confirm that cells of prostate tumors can be efficiently infected by adenoviruses, Ad-mCherry (SxWv.p./tumor) was injected directly into TRAMP mouse prostate tumors (Fig. 3C) and surgical specimens of human prostate tumors (Fig. 3D). In both cases, mCherry expression was observed in CAR-positive epithelial cells 24 hours post-infection. This finding supports the likelihood of efficient M-VM3 infection of prostate tumors in vivo.

Mobilan induces long-term activation of NF-KB

To examine M-VM3 functionality in the whole-animal setting, luciferase expression was measured in lysates of liver, intestine and prostate prepared from Balb/C-Tg(kB -luc)Xen reporter mice 48 hours after M-VM3 intravenous (IV) or intra-prostate injection (Fig. 4A). IV M-VM3 resulted in strong NF- Β activation in the liver, lesser activation in the intestine, and no significant activation in the prostate. In contrast, intra-prostate M-VM3 injection caused significant NF-κΒ activation in prostate tissue, some activation in intestine and no substantial activation in liver. Whole-body bioluminescence imaging of these mice at 3, 24 and 48 hours after intra-prostate injections showed that entolimod induced rapid NF-κΒ activation in the liver area (at 3 hours) which diminished by 24 hours. In contrast, -VM3 activated NF-κΒ slowly in the lower abdominal area (at 24 hours) and this persisted up to 48 hours.

Long-term activation of NF-κΒ by M-VM3 was also demonstrated in cultures of mouse hepatocytes carrying an NF- κ B-dependent luciferase reporter using LumiCycle (Fig. 4C). In vitro treatment of hepatocytes with CBLB502 resulted in rapid but transient NF- κ B activation. In contrast, NF- B activation in response to M-VM3 was delayed but more persistent. These findings that -VM3 is capable of establishing continuous TLR5 signaling in prostate tissue and that its delivery by intra-prostate injection largely restricts NF- κ B activation to the local area of the prostate support the feasibility of using M-VM3 to treat prostate cancer.

Intra-prostate M-VM3 injection in TRAMP mice leads to reduced prostate weight and mobilization of immune cells into the prostate

The ability of M-VM3 to suppress prostate tumor progression in the TRAMP model was tested by administering M- VM3, Ad-mCherry or PBS to 12-week old mice by intra-prostate injection. Six weeks later, mice were evaluated for presence of prostate tumors and weight of each prostate lobe (anterior, dorsal, ventral and lateral) as a measure of tumor burden within the lobe. In addition, H&E-stained sections of prostate lobes were evaluated for morphological changes. The average weight of ventral lobes (the site of injection) was significantly lower in M-VM3-treated mice compared to Ad-mCherry and PBS controls (Fig. 5B). The weight of other lobes was not significantly different between groups. These results provided an initial indication of M-VM3 anti-tumor efficacy in TRAMP mice.

Histology demonstrated that prostates from M-VM3-injected mice (Fig. 5A, B), but not from those treated with PBS or Ad-mCherry (not shown), contained single glands or groups of glands showing signs of atrophy and degeneration. This was particularly prominent in ventral lobes (site of injection) where glands appeared as an amorphous eosinophilic mass, with nuclei showing karyorhexis and karyolysis. In addition, increased presence of mononuclear (lymphoid/macrophage) cells was observed in the prostate interstitium of 12 of 15 M-VM3-treated mice (Fig. 5C) but to a lesser degree in Ad-mCherry-treated animals (6 out of 15) and was not observed in PBS-treated mice (0 out of 14).

These findings suggest, inter alia, that M-VM3-induced accumulation of mononuclear/lymphoid cells in the prostate interstitium might be involved in anti-tumor immune responses capable of suppressing tumor growth and progression in the TRAMP model.

Intra-prostate tumor injection of M-VM3 induces expression of genes involved in immune responses

To identify changes in gene expression underlying the observed mobilization of immune cells into prostate tumors following M-VM3 injection, a comparison was conducted for the global gene expression profiles of TRAMP mouse prostate tumors 24 and 48 hours after single intra-tumor (i.t.) injection of M-VM3, Ad-mCherry or vehicle using lllumina whole-genome microarrays. At 24 hours post-injection, 17 genes were induced more strongly by M-V 3 than Ad-mCherry (Supplementary Table 1). Consistent with the known mechanisms of activation of TLR5 signaling by entolimod, this list includes several NF- κ B target genes such as CXCL1, IL1B and S100A9. At 48 hours, there was a larger number of genes specifically upregulated by M-VM3- versus Ad-mCherry (57 genes, Supplementary Table 2). This list includes a number of genes encoding cytokines chemokines (IL1 B, CCL7 and 9, CXCL9, 13 and 17) which may play roles in mobilization of immune cells into tumors. Other notable M-VM3-specific induced genes are several with known roles in regulation of NF- κ B responses (e.g., IKBKE and NFKBIZ) or antiviral activity (e.g., NLRC5 and OASL1). Only four genes induced at 24 hours remained induced at 48 hours (NLRC5, CLEC4A1, IL1 B and S100A9). In particular, M-VM3-induced NLRC5 may contribute to the anti-tumor immune response and prevention of tumor immune escape through activation of expression of MHC class-l molecules and components of the antigen-processing machinery.⁴⁴

Intratumoral delivery of M-VM3 stimulates an innate immune response

To characterize immune cell infiltration into TRAMP prostate tumors in response to M-VM3, TRAMP mice with palpable prostate tumors were given an i.t. injection of PBS, Ad-mCherry or M-VM3 and prostate tumors and tumor- draining lymph nodes (TDLNs) were collected 2 or 7 days later. Since activation of TLR5 stimulates recruitment of neutrophils, NK cells, and T cells to the liver ⁶· ⁸-¹⁰, similar immune cell profiles in TRAMP prostate tumors by FACS analysis were characterized. Neutrophils were significantly recruited to the prostate on Day 2 after i.t. delivery of M- VM3 or, to a lesser extent, after Ad-mCherry (Fig. 6A). Although M-VM3 appeared to stimulate stronger recruitment of neutrophils than Ad-mCherry, this difference did not reach statistical significance (P=0.22). NK cells also responded to M-VM3, but not to Ad-mCherry and with kinetics that was different than for neutrophils and that were dependent upon virus identity (Fig. 6B). M-VM3-specific induction of NK cells was not observed until Day 7 post-i.t. injection.

The response of adaptive immunity was then characterized, which included CD8⁺ and CD4⁺ T cells. Levels of CD8⁺ T cells in TRAMP tumors did not change following i.t. delivery of either Ad-mCherry or M-VM3 on Day 7 (Fig. 6C). Similar to the CD8- T cell response, bona fide CD4⁺ T cells, which lacked FoxP3 expression and thus not Treg, showed no statistical difference at Day 7 post-i.t. injection. Lastly, the effect of i.t. viral delivery on immunosuppressive Treg was characterized in TRAMP tumors and TDLN on Day 7 post-i.t. injection. Levels of Tregs in TRAMP tumors (Fig. 6E) and TDLNs (Fig. 6F) were not significantly affected by either virus. Together, these data indicate that i.t. adenovirus (M-VM3 or Ad-mCherry) injection in TRAMP mice leads to recruitment of components of innate immunity to the prostate while having no impact on immunosuppressive Treg. The main M-VM3-specific response was recruitment of NK cells to the prostate and, to a lesser extent, neutrophil recruitment.

-VM3 has anti-metastatic activity M-VM3 anti-metastatic activity was tested in a model in which metastatic outgrowth of TRAMP-C2 prostate cancer occurs after primary tumor resection.⁴⁵ Mice with s.c. growing TRAMP-C2 tumors (-100 mm³) were given a single i.t. injection of PBS, Ad-mCherry or M-VM3. Primary tumors were removed 7 days post-injection and the animals were monitored for survival until Day 150 post-injection. As shown in Fig. 7A, M-VM3 injection prior to tumor removal improved survival to Day 150 compared to PBS and Ad-mCherry Log-rank analysis showed that the difference in mortality kinetics between the M-VM3-treated and control groups was nearly statistically significant (P=0.06). These results indicate that M-VM3 may be effectively combined with surgery to prevent prostate tumor metastasis.

M-VM3-infected cells as an anti-cancer vaccine

Stimulation of anti-tumor immunity by M-VM3 suggested that it might be useful not only as a therapy, but also as a prophylactic anti-cancer vaccine. To test this possibility, TRAMP-C2 cells were infected with M-VM3, lethally irradiated 48h later, and then used to vaccinate C57BL/6 mice. Control groups were not vaccinated or vaccinated with similarly prepared Ad-mCherry-infected or uninfected cells. Mice were vaccinated s.c. on Study Days 0, 14, and 21 and challenged with TRAMP-C2 cells by s.c. injection 14 days after the last vaccination. Subcutaneous tumor growth was monitored for 38 days post-challenge or until tumors reached the endpoint size requiring euthanasia. The percentage of mice that developed tumors was significantly lower in the group immunized with M-VM3-infected cells compared to all three control groups (Fig.7B) thus indicating efficacy of the tested M-VM3-based vaccination strategy.

Discussion.

Immunotherapeutic strategies aimed at stimulating the immune system to attack cancer cells or blocking immunosuppressive mechanisms hold strong promise for improving cancer treatment. TLR5 activation may be a particularly attractive means to stimulate anti-tumor immune responses. To expand clinical applications of TLR5- mediated immunotherapy to include tumors that do not naturally express TLR5, a novel adenovirus (Mobilan M-VM3) was generated that directs co-expression of TLR5 and a secreted entolimod-based TLR5 agonist and thereby establishes local TLR5 activation upon delivery to a tumor. Prostate cancer models were used to test M-VM3 due to the high frequency of CAR expression among human prostate tumors and previous demonstration of their efficient infection by adenoviruses.⁴⁶ This study confirmed the efficient infection of mouse prostate tumors (in vivo) and surgical specimens of human prostate tumors (ex vivo) upon direct intra-tumor injection of the adenoviruses described herein. Unlike entolimod treatment, M-VM3 established continuous local (not systemic) TLR5 signaling in TRAMP prostate cancer cells and in mouse prostate tissue following intra-prostate injection. Injection of M-VM3 into TRAMP prostate tumors suppressed tumor progression (indicated by tumor weight and histology) and led to recruitment of innate immunity, including neutrophils and NK cells. Involvement of these immune mechanisms can be explained, without wishing to be bound by theory, by the profile of M-VM3-specific gene expression observed in the microarray experiments and is consistent with earlier studies with flagellin and entolimod. The potential use of TLR5 agonists as a vaccine adjuvant is explored herein. In this study, a single intra-tumor injection of M-VM3 into s.c. growing TRAMP-C2 tumors improved mouse survival after surgical removal of the tumors, suggesting that intra-tumor vaccination with M-VM3 may be an effective strategy for preventing metastasis in prostate cancer patients. It was also determined that vaccination of mice with lethally irradiated -VM3-infected TRAMP-C2 cells (prime + 2 boosts) protected mice against a subsequent s.c. challenge with TRAMP-C2 cells. Use of cell-based vaccination against prostate cancer is illustrated by Sipuleucel-T, an FDA-approved autologous cellular vaccine consisting of a patient's dendritic cells loaded with a prostatic acid phosphatase-granulocyte/macrophage- colony stimulating factor fusion protein.²¹ Sipuleucel-T prolonged survival in men with metastatic prostate cancer but had no effect on time to progression.⁵⁵ Trials with GVAX, a vaccine comprised of prostate cancer cell lines (LnCAP and PC3) expressing GM-CSF were terminated due to a lack of overall survival benefit.^{21 24} Data presented herein suggest that M-VM3 could fill the need for more effective cell-based vaccines against prostate cancer.

Overall, among others, this work provides evidence that use of M-VM3 can establish constitutive TLR5 signaling in tumors regardless of their TLR5 expression status and demonstrates that such signaling leads to anti-tumor immune responses capable of suppressing prostate tumor development, progression and metastasis in different experimental settings.

Materials and Methods

Mice

C57BL/6 mice (6-8 week old males) were obtained from Taconic, Inc. (Hudson, NY, USA). TRAMP mice³⁷ were bred in the RPCI (Mouse Tumor Model Resource). BALB/C-Tg(l Ba-luc)-Xen mice (carrying an IKBa promoter-controlled firefly luciferase reporter transgene) were purchased from Xenogen Corporation (Alameda, CA, USA) and maintained as a colony in the RPCI animal facility. TLR5KO mice (B6.129S1-77r5^im,Rl7J) were purchased from The Jackson Laboratories (Bar Harbor, ME, USA) and maintained as above.

Reagents

Rabbit anti-CBLB502 polyclonal antibody (pAb), biotin-labeled goat anti-CBLB502 pAb and 1 B04 anti-human TLR5 monoclonal antibody (mAb) were produced by Cleveland BioLabs, Inc. (CBLI; Buffalo, NY, USA). Antibodies for immunohistology included rabbit polyclonal anti-NF-κΒ p65 (catalog #7970; Abeam, Cambridge, UK), rat monoclonal anti-cytokeratin 8 (Troma-1; Developmental Studies Hybridoma Bank, University of Iowa, Iowa City, IA, USA), and anti-CAR antibody (H-300; catalog #sc15405, Santa Cruz, CA, USA). TNFa was purchased from PeproTech Inc. (Rocky Hill, NJ, USA), and LPS from E. coli 055: B5 was purchased from Sigma-Aldrich (St Louis, MO, USA). CBLB502 and CBLB502NQ were produced as described.⁵⁶

Cultured cells The TRAMP-C2 prostate cancer cell was maintained as described.³⁷ To develop stable NF- κ B-luc reporter cell lines, OSEC cells (from Dr. A. Odunsi, RPCI, Buffalo, NY, USA) and TRAMP-C2 cells were transduced with Lenti NF-KB

Reporter (QIAGEN, Frederick, D, USA) followed by puromycin selection. Primary mouse hepatocytes were isolated as described.⁵⁷

Adenoviruses

Adenovirus constructs (Ad-mCherry, obilan M-0 and M-V 3) were prepared using the AdMax™ system (Microbix Biosystems, Mississauga, Canada). Expression cassettes were assembled in shuttle plasmid pDC515 and Ad genomic plasmid pBHGIoxAE1,3Cre was used for recombination to obtain final constructs. Resulting viruses were plaque-purified, amplified and purified in CsCI gradient. Mobilan M-0, M-VM3 and Ad-mCherry stocks contained 1x10¹², 1.1x10¹² and 1x10 ²vp/ml, respectively.

Luciferase assays

NF-KB-dependent luciferase expression in reporter cell lines and In extracts of reporter mouse organs was measured as described in references ⁵⁶ and ³ respectively.

Imaging of NF-KB-driven luciferase expression in live mice

Bioluminescence imaging was performed using the S 50 imaging system (Xenogen) as described.⁴³

NF- K B-driven luciferase expression in live cells

Mouse NF-KB-luc-hepatocytes were infected with M-VM3 or Ad-mCherry (MOI=10⁴) or treated with entolimod (0.1 Og/ml) or PBS. The virus-containing medium was replaced with fresh medium after 3 h (1 h in case of entolimod) and luciferin was added to the cells. Luciferase activity was measured in LumiCycle 32 (Actimetrics, Wilmette, IL, USA) for 3 days. Baseline level of luciferase activity was subtracted.

ELISA and Western blot

CBLB502 and its derivatives were detected by ELISA⁵⁸ and Western blot using CBLB502-specific pAbs and TLR5 was detected by Western blot using 1 B04 mAb (see Reagents).

Immunohistochemistry

Sections of tumor tissues and cultured cells were stained as described.⁴³ Primary antibodies: anti-NF- Β p65 (Abeam, cat. #7970), anti-cytokeratin 8 (Troma-1 ; Developmental Studies Hybridoma Bank, University of Iowa), anti- CAR (SantaCruz, cat.#sc-15405), anti-integrin alpha 6 (Abeam, cat. #ab62844-100). Images were obtained using an Axio Imager Z1 (Carl Zeiss, Jena, Germany) fluorescent microscope equipped with a high sensitivity CCD digital camera MRm (Carl Zeiss) and AxioVision software (release 4.8.3).

Deglycosylation of CBLB502 MOSEC cultures at 50% confluence were infected with M-0 (1x10^s v.p./ml). After 48h, cell extracts were prepared using CelLytic M (Sigma-Aldrich). Lysates were cleared by centrifugation and desalted using spin columns. Deglycosylation was performed with the Protein Deglycosylation Mix reagent kit (New England Biolabs, Ipswich, MA, USA) according to manufacturer's protocol.

Infection of mouse and human tumors with Ad-mCherry

1x10⁷ TRAMP-C2 cells were injected into mice s.c. Ad-mCherry (2x10⁹ v.p.in total) was injected in 3 different points of each tumor (-100 mm³). Samples of human prostate tumors were dissected into 0.5x0.5x1cm pieces and 2 pieces from each patient were injected with Ad-mCherry as for mouse tumors. Injected human samples were cultivated in enriched DMEM additionally supplemented with 5og/ml insulin and 10⁸ M dihydrotestosterone at 37°C, 5% C0₂. Prostate injection

The abdomens of anesthetized TRAMP mice were shaved. Using aseptic technique, a 1 cm incision was made with scissors above the prostate on the ventral side of the animal through the skin and body wall and ICPv.p.^ Dl in total) of M-VM3, Ad-mCherry or PBS were injected into 3 points of the prostate ventral lobe. The body wall was closed with 1-2 sutures and the skin was closed with wound clips.

Cell-based immunization of mice

70% confluent TRAMP-C2 cells were infected with M-VM3 or Ad-mCherry (MOI=1.2x10⁵) and 48h later irradiated (50 Gy dose, Gamma irradiator Shepherd 4,000Ci Cesium-137 source). C57BL/6 mice (n=10/group) were left unvaccinated or vaccinated s.c. with uninfected, M-VM3- or Ad-mCherry-infected cells (IxlO^ells/mouse) on Study Days 0, 14, and 21. Mice were challenged with TRAMP-C2 cells (1x10⁷ cells/per mouse, subcutaneous injection). 14 days after the last vaccination. Tumor growth was monitored for 38 days post-challenge.

Surgical removal of TRAMP-C2 tumors after i.t. injection M-VM3

Tumors (-100 mm³) that developed in C57BL/6 mice 4 weeks after TRAMP-C2 cell s.c. inoculation (1x10⁷ cells/mouse) were injected i.t. with PBS, Ad-mCherry (10⁸ vp) or M-VM3 (10⁸ vp) (50 μΙ/tumor). Tumors were surgically removed 7 days post-injection as described.⁴⁵

FACS analysis of immune cell populations

M-VM3- or Ad-mCherry- or PBS-injected tumors were harvested 2, 7 or 14 days post-injection and weighed. Single- cell suspensions were generated and analyzed by FACS as described. ⁴³

Microarray Analysis

Gene expression profiling was accomplished using Mouse WG-6 whole-genome gene expression assay and direct hybridization assay (lllumina, San Diego, CA, USA). RNA was prepared 24 and 48h after injection with M-VM3, Ad- mCherry (10⁹ .p, 50 Dl total into 3 points) or PBS (2 mice/group) into palpable spontaneous prostate tumors of TRAMP mice (22-26 weeks old). Quantile normalization and background subtraction was conducted using lllumina Genestudio. Genes that had a minimum signal of 50 in both adenoviral-infected replicates and were induced at least two-fold by Ad-mCherry or M-VM3 as compared to PBS were considered induced for the purposes of analysis. Figure legends

Figure 1. Adenoviral constructs and their characterization in vitro.

(A) Schematic representation of expression cassettes in (a) Mobilan M-0, (b) Mobilan M-VM3, and (c) Ad-mCherry. P - promoter, T - transcription terminator. (B) Western blot analysis of Mobilan-directed protein expression in MOSEC cells, (a) Detection with anti-TLR5 antibody; lysates from un-infected (lane 1) and M-0 infected MOSEC cells (lane 2). (b) Detection with rabbit anti-CBLB502 pAb; lysates from Μ-0-infected MOSEC cells left untreated (lane 1) or treated with a mixture of de-glycosylation enzymes (lane 2). (C) Activity comparison of £. co//-produced CBLB502 and CBLB502NQ in HEK293-NF-KB-JacZ reporter cells. Cells were incubated with purified proteins for 24 h; β- galactosidase activity (OD414) was measured in cell lysates using ONPG substrate. (D) Western blot analysis of MOSEC cells infected with Ad-mCherry (lane 1), M-0 (lane 2) or M-VM3 (lane 3) using rabbit anti-CBLB502 PAb. The protein with slower mobility in lane 3 is the expected size of unglycosylated CBLB502NQs (31.5 kDa); the faster mobility protein is presumably a partially degraded form of CBLB502NQs. (E) Activity comparison of CBLB502s and CBLB502NQs produced in MOSEC cells. MOSEC cells were infected with M-0 or M-VM3, medium was collected after 48h and the concentrations of CBLB502s and CBLB502NQs were measured by ELISA after heat-inactivation of residual adenovirus. The indicated 'amounts of MOSEC-produced proteins or £ co//-produced CBLB502 standard were applied to HEK293-NF-KB-lacZ cells and β-galactosidase was measured as above. (F) Effect of neutralizing anti-CBLB502 antibodies on TLR5 signaling in M-VM3-infected MOSEC-NF-KB-luciferase reporter cells. Cells were infected with M-VM3 in the presence or absence of an excess of neutralizing rabbit anti-CBLB502 pAb. Luciferase activity was measured after 80 hours incubation. Error bars represent the standard deviation of triplicate measurements.

Figure 2. M-V 3 induces activation of NF- κ B in reporter cell lines.

(A-B) Infection with M-VM3 (MOI=3x10*) induces NF-κΒ p65 nuclear translocation in TLR5-negative MOSEC cells 24h after infection (B, white arrow) compared to control uninfected MOSEC cells (A, empty arrow). Antibodies against NF-κΒ p65 were used for immunostaining. (C) Induction of NF-xB-dependent luciferase expression in TRAMP-C2 cells infected by M-VM3. TRAMP-C2 cells carrying an NF-KB-dependent luciferase reporter construct were infected with M-VM3 or Ad-mCherry at the indicated MOIs. Luciferase activity was measured in lysates prepared 48h postinfection and is shown as a percentage of that in uninfected cells (set at 100%).

Figure 3. Mouse and human prostate tumors express CAR and are efficiently infected by Ad-mCherry. (A) A representative area of a human prostate tumor microarray (RPGI) stained with anti-CAR antibodies (T - tumor and N - normal prostate tissue samples). (B) Expression of CAR (green) in TRA P-C2 cells revealed by immunofluorescent staining with anti-CAR antibodies. (C) A TRAMP mouse prostate tumor was injected with Ad- mCherry (5x10⁸ ν.ρ,/tumor). 24h later, CAR (green) and mCherry (red) expression were detected in tumor epithelial cells positive for CK8/18, a marker of epithelial cells (lilac). The upper left panel shows an overlay of CAR and mCherry fluorescence. (D) A human prostate tumor surgical sample (RPCI) was injected with AdCherry (5x10⁸ v.p./tumor). 24h later, CAR (green) and mCherry (red) expression was detected in tumor epithelial cells positive for Troma I, a marker of epithelial cells (lilac). The upper left panel shows an overlay of CAR and mCherry fluorescence. Figure 4. Induction of NF-κΒ activity in reporter mice after administration of M-VM3.

(A) Measurement of luciferase activity in liver (L), intestine (I) and prostate tissue (P) extracts of NF-xB-luciferase reporter mice BALB/C-Tg(lkBa-luc)-Xen after intra-venous and intra-prostate injections (48h) of M-VM3. Relative light unit (RLU) values (per mg of total protein) in tissue extracts of M-VM3-treated mice were calculated by subtraction of RLU values for PBS-treated mice. (B) BALB/C-Tg(lkBa-luc)-Xen mice were given a single intra-prostate injection of PBS, CBLB502 (1 g/mouse) or M-VM3 (1x10⁹ v.p.) and analyzed 3, 24 or 48 hours later by whole-body Xenogen bioluminescence imaging of live anesthetized animals. C) M-VM3 induces long-term activation of NF-κΒ in live mouse hepatocytes carrying an introduced NF-xB-dependent luciferase reporter construct. Cells were infected with M-VM3 ( OI=10⁴) or Ad-mCherry (MOI=10⁴) or treated with entolimod (0.1 mg/ml) or PBS (control), then these agents were removed from the media (3 hours for Ad and 1 hour for entolimod) and luciferase was measured by LumiCycle. The level of luciferase activity from PBS-treated cells was subtracted.

Figure 5. In vivo effect of M-VM3 on prostate tumors in mouse TRAMP model.

(A, B) Increased infiltration of lymphoid/mononuclear/macrophage cells (red arrowhead) in the interstitium between prostate lobes in M-VM3-injected TRAMP mice (A) compared to PBS-injected TRAMP mice (B). H&E-stained prostate sections were prepared 6 weeks after intraprostate injection of M-VM3 or PBS. (C, D) Atrophic and degenerative changes (areas with red asterisks) in cells and whole lobes of prostates from TRAMP mice treated with M-VM3. H&E-stained prostate sections were prepared 6 weeks after intraprostate injection of M-VM3. C and D show two independent examples from different M-VM3 treated mice. (E) Average weight of prostate ventral lobes 6 weeks after intraprostate injections of M-VM3, Ad-mCherry and PBS of forty-five 12 week-old TRAMP mice (15 mice per group, error bars indicate standard error of mean).

Figure 6. Quantitative analysis of innate and adaptive immune cell populations recruited to TRAMP tumors and TDLNs following i.t. injection of Ad-mCherry or M-VM3.

Palpable spontaneously developed prostate tumors (A - E) and TDLNs (F) from tumor-bearing TRAMP mice were collected 2 (for neutrophils) or 7 days (for NK and T cells) after i.t. injection of PBS (vehicle), Ad-mCherry (control) or M-VM3 (10⁹ v.p total per 3 points). Specific immune cell populations within the samples were quantified by FACS and are reported as absolute number of cells per gram of prostate tissue or per TDLN. (A) Neutrophils were defined as CD45⁺CD11 b⁺CD11c Ly-6Cw-Ly-6G^H; (B) NK cells were defined as CD45^CD3 NK1.1⁺; (C) CD8⁺ T cells were defined as CD45⁺CD30⁺CD8^ (D) CD4* T cells were defined as CD45⁺CD30⁺FoxP3-CD4⁺; and (E) Tregs were defined as CD45*CD30⁺CD4⁺FoxP3⁺. Data are shown as mean ± SEM (N = 3-7 mice/group).

Figure 7. Anti-tumor effects of M-VM3.

(A) TRA P-C2 tumors were grown s.c. in C57BL/6 mice and injected i.t. with PBS, Ad-mCherry (5x10⁸ v.p.) or - V 3 (5x10^s v.p.) on Day 0. Tumors were surgically removed on Day 7 and the mice were monitored for survival until Day 150. (B) C57BL/6 mice (n=10 per group) were vaccinated s.c. with M-VM3- or Ad-mCherry-infected (irradiated 48h after virus infection) or uninfected irradiated TRAMP-C2 cells. A fourth group of mice was not vaccinated. Mice were vaccinated on Days 0, 14, and 21 and then challenged with TRAMP-C2 cells by s.c. injection 14 days after the last vaccination. Tumor growth was monitored for 38 days post-challenge or until tumors reached the endpoint size requiring euthanasia. % of tumor-free mice was determined at Day 38 post-challenge.

Supplementary figure legends

Figure S1. Production of CBLB502NQs in MOSEC cells and titration of neutralizing antibodies.

(A) CBLB502NQs production by M-V 3 in MOSEC cells. MOSEC-NF-icB-luciferase reporter cells were infected with the indicated titers of M-VM3 and incubated for 80 hours; CBLB502NQs concentration in cell culture medium was measured by ELISA. (B) Inhibition of CBLB502 activity by anti-CBLB502 antibodies. HEK293-NF-«B-lacZ reporter cells were incubated with CBLB502 (0.01-25 ng/ml) in the presence or absence of neutralizing rabbit anti-CBLB502 pAb for 16 hours and β-galactosidase was measured in cell lysates using ONPG substrate. Error bars represent the standard deviation of triplicate measurements.

Figure S2. TLR5 and TLR4 expression status of MOSEC cells.

(A-C) MOSEC cells express functional TLR4, but not TLR5. MOSEC cells were treated with PBS (A), 100 ng/ml CBLB502 (B), or 100 ng/ml LPS (C) for 30 minutes after which nuclear translocation of the p65 subunit of NF-κΒ was detected by immunohistochemistry. p65 nuclear translocation was observed in -100% of LPS-treated cells, but not in entolimod- or PBS-treated cells. (D-l) Immunohistochemical detection of the p65 subunit of NF-κΒ (green, panels D and G) and hTLR5 (red, panels E and H) in hepatocytes from TLR5KO mice infected with M-VM3 (MOI=3x10⁴; panels G-l) or left uninfected (panels D-F). Panels F and I show DAPI (blue) staining of nuclei. Staining was performed 24h after infection. KTLR5 expression and NF-κΒ p65 nuclear translocation were observed in the majority of M-VM3-infected hepatocytes from TLR5KO mice (H and G, respectively), but not in corresponding uninfected control TLR5KO hepatocytes (E, D).

Figure S3. CAR status of human tumors.

Human multi-tumor tissue microarray was stained with anti-CAR antibodies. A representative panel of three replicates is shown. The sample layout is presented in Supplementary Table 3.

Supplementary tables Supplementary Table 1. Genes induced in TRAMP tumors at 24 h after intra-tumor injection of M-VM3 or Ad- mCherry.

Supplementary Table 2. Genes induced in TRAMP tumors at 48 h after intra-tumor injection of M-VM3 or Ad- mCherry.

Supplementary Table 3. The layout of different tumor and normal tissue samples on the multi-tumor tissue microarray used for determination of CAR expression (Figure S3).

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Claims

CLAIMS What is claimed is:

1. A method of preventing or reducing pre-cancerous changes in the prostate of a subject comprising, administering to the subject a vector comprising a first and second nucleic acid, wherein the first nucleic acid encodes TLR5 and the second nucleic acid encodes a secreted form of flagellin.

2. A method of preventing or reducing pre-cancerous changes in the prostate of a subject comprising, administering to the subject a cell transduced with a vector comprising a first and second nucleic acid, wherein the first nucleic acid encodes TLR5 and the second nucleic acid encodes a secreted form of flagellin.

3. The method of claim 2, wherein the cell is a normal, premalignant, or malignant cell derived from the subject.

4. The method of any one of claims 1-3, wherein the pre-cancerous changes comprise formation and progression of prostatic intraepithelial neoplasia (PIN) and/or proliferative inflammatory atrophy (PIA).

5. The method of claim 4, wherein the method prevents the progression of PIN and/or PIA into prostate cancer in the subject.

6. A method of treating prostate cancer in a subject in need thereof of comprising, administering to the subject a vector comprising a first and second nucleic acid, wherein the first nucleic acid encodes TLR5 and the second nucleic acid encodes a secreted form of flagellin; and wherein the prostate cancer is selected from prostate adenocarcinoma, prostate small cell carcinoma, prostate squamous cell carcinoma, prostatic sarcoma, prostate transitional cell carcinoma, and/or benign prostatic hyperplasia (BPH).

7. A method of treating prostate cancer in a subject in need thereof of comprising, administering to the subject a cell transduced with a vector comprising a first and second nucleic acid, wherein the first nucleic acid encodes TLR5 and the second nucleic acid encodes a secreted form of flagellin; and wherein the prostate cancer is selected from prostate adenocarcinoma, prostate small cell carcinoma, prostate squamous cell carcinoma, prostatic sarcoma, prostate transitional cell carcinoma, and/or benign prostatic hyperplasia (BPH).

8. The method of claim 7, wherein the cell is a normal, premalignant, or malignant cell derived from the subject.

9. The method of any one of claims 6-8, wherein the prostate cancer is prostate adenocarcinoma.

10. A method of preventing prostate cancer metastasis in a subject in need thereof of comprising, administering to the subject a vector comprising a first and second nucleic acid, wherein the first nucleic acid encodes TLR5 and the second nucleic acid encodes a secreted form of flagellin; and wherein the method prevents metastasis to one or more of lymph nodes, lungs, bones including spinal columns, livers, and/or the brain,

11. A method of preventing prostate cancer metastasis in a subject in need thereof of comprising, administering to the subject a cell transduced with a vector comprising a first and second nucleic acid, wherein the first nucleic acid encodes TLR5 and the second nucleic acid encodes a secreted form of flagellin; and wherein the method prevents metastasis to one or more of lymph nodes, lungs, bones including spinal columns, livers, and/or the brain.

12. The method of claim 11 , wherein the cell is a normal, premalignant, or malignant cell derived from the subject.

13. The method of any one of claims 10-12, wherein the method further comprises administration of an immune- modulating agent.

14. A method of preventing prostate cancer recurrence in a subject in need thereof of comprising, administering to the subject a vector comprising a first and second nucleic acid, wherein the first nucleic acid encodes TLR5 and the second nucleic acid encodes a secreted form of flagellin.

15. A method of preventing prostate cancer recurrence in a subject in need thereof of comprising, administering to the subject a cell transduced with a vector comprising a first and second nucleic acid, wherein the first nucleic acid encodes TLR5 and the second nucleic acid encodes a secreted form of flagellin.

16. The method of claim 15, wherein the cell is a normal, premalignant, or malignant cell derived from the subject.

17. The method of any one of the above claims, wherein the vector is an adenoviral vector.

18. The method of any one of the above claims, wherein the TLR5 is a human TLR5.

19. The method of claim 18, wherein the human TLR5 comprises an amino acid sequence as depicted in Figure 9.

20. The method of any one of the above claims, wherein the secreted form of flagellin comprises an amino acid sequence as depicted in Figure 7.

21. The method of any one of the above claims, wherein the vector further comprises a leader sequence.

22. The method of claim 21, wherein the leader sequence is an alkaline phosphatase leader sequence.