WO2017147820A1

WO2017147820A1 - Dual-targeting drug carrier

Info

Publication number: WO2017147820A1
Application number: PCT/CN2016/075329
Authority: WO
Inventors: 张正; 蓝耿立; 王信二; 张顺福; 李佳哲; 詹佩嘉
Original assignee: 法玛科技顾问股份有限公司
Priority date: 2016-03-02
Filing date: 2016-03-02
Publication date: 2017-09-08
Also published as: CN108699164A; CN108699164B

Abstract

Provided is a dual-targeting drug carrier, comprising a first targeting molecule and a second targeting molecule. The targeting molecule comprises a peptide, an antibody, or a protein. The targeting molecule is able to bind to a specific receptor or a specific protein or glycoprotein. The target molecule can also conjugate with a radiation therapy material to form a conjugate.

Description

Double target drug carrier

Technical field

The present invention relates to a novel target drug carrier, and in particular to a dual target drug carrier having two target molecules.

Background technique

Cancer is the leading cause of death in the United States, and cancer mortality continues to increase. Cancer is the inability of cells to divide, grow and differentiate normally. The initial clinical manifestations of cancer are extremely uneven, with almost 70 cancers occurring in human organs and tissues, and some of these similar cancer types belong to many different molecular diseases. Unfortunately, some cancers may have no actual symptoms until late in the course of the disease, making treatment and prognosis extremely difficult.

Cancer treatment usually includes surgery, chemotherapy, and/or radiation therapy. All current therapies have serious side effects and reduce the quality of life. Most chemotherapeutic drugs act on both normal and cancerous tissues. Therefore, one of the challenges in treating cancerous tumors is to give cancer cells maximum killing while minimizing damage to healthy tissue. Depending on the drug (eg, intravenous) and nature of the route of administration (eg, its physical and pharmacokinetic properties), typically only a small fraction of the administered dose reaches the target cell, with the remainder acting on other tissues or rapidly disappearing.

In order to improve delivery efficiency and reduce toxic non-cancerous cells, there have been various ways of delivering drugs to specific sites in the human body. For example, the use of monoclonal antibodies to treat cancer. Resistance The body provides target selectivity, but there are still problems with expensive and interaction with non-target cells.

In recent years, efforts have been made to find specific targets for tumor angiogenesis to develop novel target therapeutic drugs. Tumor neovascular endothelial cells express a large number of specific membrane proteins, including αvβ3, αvβ5, integrin, and vascular-related growth factors. In addition, past studies have found that short-chain peptides (RGD, NGR) have a very high recognition of tumor angiogenesis endothelial cells.

However, tumor cells are highly unstable and variability, and are resistant to drugs during treatment. At present, various drugs and diagnostic agents are still slow and ineffective in improving the survival of cancer patients.

Summary of the invention

In view of the problems with the prior art described above, the present invention provides a novel vector that can be used to diagnose and treat cancer. The dual target drug carrier of the invention is a fusion protein platform, which can effectively reduce the threshold and cost of the pharmaceutical technology.

The invention provides a dual target drug carrier comprising a first target molecule and a second target molecule.

In an embodiment of the invention, wherein the first or second target molecule specifically binds to vascular endothelial cells in tumor cells or/and tumor microenvironment

In an embodiment of the invention, wherein the first and second target molecules include, but are not limited to, arginine-glycine-aspartate (RGD), asparagine-glycine-arginine (NGR) ), cyclic NGR (cyclic asparagine-glycine-arginine), internalization of RGD (iRGD, internalization-arginine-glycine-aspartate), cystine-glycine-aspartate Acid-lysine-arginine-threonine-arginine-glycine-alanine (CGNKRTRGA), stomach Gastrin, bombesin, octreotide or a derivative thereof. Macromolecular peptides include, but are not limited to, epidermal growth factor (EGF), anti-EGFR (epidermal growth factor receptor) antibody, vascular endothelial growth factor (VEGF), anti-VEGFR ( Vascular Endothelial Growth Factor Receptor, anti-HER2 (human epidermal growth factor receptor 2) antibody, hepatocyte growth factor receptor (HGFR), anti-HIV - HGFR antibody, tumor necrosis factor (TNF) or anti-TNF antibody.

In an embodiment of the invention, wherein the first target molecule is linked to the second target molecule by a linker.

In an embodiment of the invention, wherein the connector is a peptide having 5 to 20 amino acids.

In an embodiment of the invention, wherein the linker comprises, but is not limited to, GG, PGGGG or GGGGSGGGGS, wherein G represents glycine, P represents proline, and S represents serine.

In an embodiment of the invention, a radioisotope is further included.

The invention further provides a pharmaceutical composition comprising the above dual target pharmaceutical carrier and a pharmaceutically acceptable carrier.

In an embodiment of the invention, a liposome is further included.

In an embodiment of the invention, nanoparticles are further included.

detailed description

Figure 1A shows purified VEGF, RGD-VEGF, RGD4C-VEGF, EGF, SDS-PAGE electropherogram of RGD-EGF and RGD4C-EGF protein.

Figure 1B is a SDS-PAGE electrophoresis map of marker, VEGF, RGD-VEGF, and RGD4C-VEGF, wherein M is marker, 1 is VEGF (15.3 Da), 2 is RGD-VEGF (15.6 Da), and 3 is RGD4C-VEGF ( 16.3Da).

2A-2F are binding curves/bar graphs of RGD-VEGF and RGD4C-VEGF and αvβ3, VEGFR1, VEGFR2. RGD-EGF and RGD4C-EGF bind to αvβ3 and EGFR, respectively. Figure 2A is a graph showing the binding of RGD-VEGF and RGD4C-VEGF to αvβ3. Figure 2B is a bar graph of competition of RGDfV polypeptide with RGD-VEGF and RGD4C-VEGF in combination with αvβ3. Figure 2C is a graph showing the binding of RGD-VEGF and RGD4C-VEGF to VEGFR1. Figure 2D is a graph showing the binding of RGD-VEGF and RGD4C-VEGF to VEGFR2.

Figure 2E is a bar graph of competition of VEGFR2 antibodies by RGD-VEGF and RGD4C-VEGF in combination with VEGFR2. Figure 2F is a graph showing the binding of RGD-EGF and RGD4C-EGF to αvβ3.

Figure 3A is a graph showing the binding of U87MG (expressing αvβ3 and EGFR) cells to RGD-VEGF and RGD4C-VEGF. RGD-VEGF and RGD4C-VEGF can bind to αvβ3 and EGFR, respectively.

Figure 3B is a bar graph of binding of U87MG (expressing αvβ3 and EGFR) cells to RGD-VEGF and RGD4C-VEGF.

Figure 3C is a graph showing the binding of HUVEC (expressing VEGFR1, VEGFR2 and αvβ3) cells to RGD-VEGF, RGD4C-VEGF and NGR-VEGF. RGD-VEGF, RGD4C-VEGF and NGR-VEGF can bind to express VEGFR1 Cells of VEGFR2 and αvβ3.

Figure 3D is a bar graph of binding of HUVEC (expressing VEGFR1, VEGFR2 and αvβ3) cells to RGD-VEGF, RGD4C-VEGF and NGR-VEGF.

Figures 4A-4D are cell adhesion assays. After coating RGD-VEGF and RGD4C-VEGF on the cell plate, the number of U87MG cells and HUVEC cells attached to the culture plate can be increased. If a large amount of RGD peptide chain is added to compete, the adsorption of cells can be reduced. 4A shows that RGD-VEGF and RGD4C-VEGF are applied to the cell plate to increase the number of U87MG cells attached to the culture plate, and FIG. 4B shows the amount of cells attached to the culture plate after the addition of the RGDfV polypeptide. Inhibition, Figure 4C-4D shows that RGD-VEGF and RGD4C-VEGF bind to HUVEC cells, and then compete with RGDfV polypeptide or VEGFR2 recombinant protein, respectively, in terms of absorbance and percentage.

Figures 5A-5B show that RGD-EGF and RGD4C-EGF or RGD-VEGF and RGD4C-VEGF activate a signaling pathway downstream of EGFR or VEGFR, respectively. The EGF or VEGF of the dual target drug carrier of the invention retains its original biological properties. Among them, M of Figure 5A is Marker, C is the control group (no protein added), E is EGF (25 nM), RE is RGD-EGF (25 nM), and R4C-E is RGD4C-EGF (25 nM), while C of Figure 5B For the control group (no protein added), RV is RGD-VEGF, R4-V RGD4C-VEGF.

Figure 6 is a graph showing the stability of a radiolabeled fusion protein in a buffer solution (HEPES, 4 ° C) and serum (37 ° C). The radiolabeled fusion protein was stored in Hepes buffer (4 ° C) and fetal bovine serum (37 ° C), and the radiochemical purity was still higher than 90% after 24 hours, indicating the radioactive In-111-labeled fusion protein. The serum stability is excellent.

Fig. 7 is a fluorescent photograph. The RGD-VEGF and RGD4C-VEGF marker recombinant proteins can bind to cells.

Figure 8 is a single photon and computed tomography (SPECT/CT) angiogram of radiolabeled recombinant protein. U87MG subcutaneous tumor mice were injected with ¹¹¹ In-DTPA (Diethylene triamine pentacetate aci)-EGF, ¹¹¹ In-DTPA-RGD-EGF and ¹¹¹ In-DTPA-RGD4C-EGF. Small animal single photon and computed tomography (SPECT/CT) angiography was performed at 4, 8 and 24 hours. The image shows that after the In-111 marker recombinant protein is applied, the specific accumulation of the tumor in the tumor (expressed as the tumor/muscle accumulation ratio) increases with time, reaching a peak at 8 hours after the drug injection, at this time ¹¹¹ In The tumor/muscle accumulation ratio of -DTPA-RGD4C-EGF was 4.4, slightly higher than 3.6 of ¹¹¹ In-DTPA-RGD-EGF, and much higher than 1.7 of ¹¹¹ In-DTPA-EGF.

detailed description

The target molecule of the present invention is a peptide, antibody or protein. The target molecules of the invention can be chemically modified to increase stability. Chemically modified peptides or peptide analogs include any chemically functional equivalent that increases stability and/or potency either in vivo or in vitro. A peptide analog refers to an amino acid derivative of any peptide. Peptide analogs include, but are not limited to, modified branches upon synthesis, combined with unsaturated amino acids and/or derivatives thereof, cross-linking and other methods that increase the peptide identity. For example, a branched modification includes a modification of an amine group.

The target molecule can bind to the lesion tissue in vivo and in vitro, especially for vascular endothelial cells of tumor, cancer tissue/cell and tumor microenvironment. Therefore, when the target peptide is conjugated to a reporter molecule (bioimaging fluorescent molecule or radiation), the tumor target peptide can directly display the tumor location and contribute to the diagnosis of cancer. "Conjugation" as used in the present invention means that two molecules that contribute to the treatment/diagnosis of a tumor, such as a tumor target peptide and a reporter molecule, are bound by sufficient affinity. Conjugation can be accomplished by covalent, non-covalent bonds or other forms of bonding, for example, coating.

The target molecule of the present invention may be a small molecule peptide and/or a macropeptide. Small molecule peptides include, but are not limited to, lysine-glycine-aspartate (RGD), asparagine-glycine-arginine (NGR), cyclic NGR, internalization RGD (iRGD), cystine - glycine-aspartate-lysine-arginine-threonine-arginine-glycine-alanine (CGNKRTRGA), gastrin, bombesin, octreotide Octreotide) or a derivative thereof. Macromolecular peptides include, but are not limited to, epidermal growth factor (EGF), anti-EGFR antibodies, vascular endothelial growth factor (VEGF), anti-VEGFR antibodies, anti-HER2 antibodies, hepatocyte growth factor receptor (HGFR), Anti-HGFR antibody, tumor necrosis factor (TNF) or anti-TNF antibody.

In an embodiment, the target molecule can form a conjugate with an imaging substance or a radiotherapeutic substance (radiopharmaceutical or isotope).

Radioactive imaging materials include, but are not limited to, ¹²² I, ¹²³ I, ¹²⁴ I, ¹²⁵ I, ¹³¹ I, ¹⁸ F, ⁷⁵ Br, ⁷⁶ Br, ⁷⁶ Br, ⁷⁷ Br, ²¹¹ At, ²²⁵ Ac, ¹⁷⁷ Lu, ¹⁵³ Sm , ¹⁸⁶ Re, ¹⁸⁸ Re, ⁶⁷ Cu, ²¹³ Bi, ²¹² Bi, ²¹² Pb and ⁶⁷ Ga.

Radiopharmaceuticals include, but are not limited to, ¹¹¹ In hydroxyquinoline, ¹³¹ I sodium iodide, ^99m Tc phenyl bromide, ^99m Tc red blood cells, ¹²³ I sodium iodide, ^99m Tc Exametazime, ^99m Tc large particle polymeric albumin, ^99m Tc-methylene phosphonate, ^99m Tc Mertiatide, ^99m Tc hydroxymethylene diphosphonate, ^99m Tc triamine pentaacetic acid, ^99m Tc Pertechnetate, ^99m TcSestamibi, ^99m Tc sulphur colloid, ^99m Tc Tetrofosmin, ²⁰¹ Tl and ¹³³ Xe .

Radiation isotopes include, but are not limited to, ⁵² Fe, ⁵² mMn, ⁵⁵ Co, ⁶⁴ Cu, ⁶⁷ Ga, ⁶⁸ Ga, ⁹⁹ mTc, ¹¹¹ In, ¹²³ I, ¹²⁵ I, ¹³¹ I, ³² P, ⁴⁷ Sc, ⁶⁷ Cu, ⁹⁰ Y, ¹⁰⁹ Pd, ¹¹¹ Ag, ¹⁴⁹ Pm, ¹⁸⁶ Re, ¹⁸⁸ Re, ²¹¹ At, ²¹² Bi, ²¹³ Bi, ¹⁰⁵ Rh, ¹⁵³ Sm, ¹⁷⁷ Lu and ¹⁹⁸ Au.

The tumor target peptide or its conjugate described in the present invention can be administered by parenteral, topical, rectal, nasal, vaginal, implantation, or spray inhalation. "Non-gastrointestinal" as used in the present invention includes subcutaneous, intradermal, intravenous, intramuscular, articular, arterial, synovial, focal or intracranial injections.

The "linker" as used in the present invention refers to a sequence of 2 to 50 synthetic amino acids, preferably 5 to 20 synthetic amino acids, which are linked to two peptide sequences, for example, to link two peptide structures. The connector of the present invention can link two amino acid sequences through a peptide bond. The linker peptide of the present invention is a linear sequence linking the first portion to the second portion. In an embodiment, the replaceable connector may be (GGGGS)n, (G)n, (EAAAK)n, (XP)n or (PAPAP)n, eg, GG, GGSG, GGGS, GGGGS, GGSGG, GGGSGG, GGGSGGG, GGGSGGGS, GGGSGGGGS, ASGG, GGGSASGG, SGCGS, GGGGSGGGG, GGSHG, SGCGGGS, and AACAA, wherein said G represents glycine; said S represents serine; said E represents glutamic acid; said A represents alanine; K represents lysine; P represents valine; said H represents histidine; and C represents cystine.

In summary, the dual target drug carrier of the present invention can carry a tumor therapeutic drug or It is a substance (such as a therapeutic radionuclide) that becomes a tumor target drug carrier. In addition, a drug capable of molecular imaging can also be carried as a molecular imaging probe for tumor diagnosis. The double target developer carrier of the invention has the effect of tumor diagnosis.

Example 1

1. Preparation of fusion protein bodies

EGF, RGD-EGF, RGD4C-EGF, VEGF, RGD-VEGF and RGD4C-VEGF genes were constructed in the expression vector of pET28a(+) with Nco I and Xho I restriction enzyme cleavage sites. The C-terminus (ie, the carbon terminus) of RGD and RGD4C is ligated to the N-terminus (ie, the nitrogen terminus) of EGF or VEGF, and the C-terminus of EGF or VEGF has a His ₆ flag. The His ₆ marker facilitates subsequent purification and analysis, wherein the gene sequences of RGD-EGF, RGD4C-EGF, RGD-VEGF, and RGD4C-VEGF comprise the linker GG. The constructed pET28a(+) EGF, RGD-EGF, RGD4C-EGF, VEGF, RGD-VEGF and RGD4C-VEGF expression vectors were transfected into E. coli.DH5α to produce and preserve vector DNA. The sequence was confirmed by DNA sequencing.

2. Expression and purification of target fusion protein

The vector of Example 1 was sent to E. coli BL21 (DE3) by heat shock, and screened and confirmed by kanamycin (50 μg/mL). The E. coli BL21 (DE3) strain carrying the protein expression vector was induced with 1 mM IPTG for 16 hours at 37 °C. The bacterial solution was sterilized by a French press at a pressure of 30 PSI, centrifuged at 13,000 g for 30 minutes, and samples of the supernatant and the pellet were collected for SDS-PAGE electrophoresis analysis, and observed by SDS-PAGE. Performance to the target fusion protein. If it is in the form of an insoluble body, the bacteria are present in the form of an insoluble body. Subsequent protein production receives a pellet after the disruption for protein purification. The lysed target fusion protein was filtered through a 0.45 μm filter, followed by a 1:50 ratio of refolding buffer (20 mM Tris, 0.1 Mm GSSG, 1 mM GSH, 1 mM EDTA pH 8.0). Dilution refolding. The target protein sample was slowly added to the refolding buffer, and the concentration of the target fusion protein after dilution was not more than 0.2 mg/ml, and the renaturation was carried out at 4 ° C for 12 hours, and then filtered through a 0.45 μm filter to remove the precipitate. Target protein.

The protein refolding solution was passed through a nickel column at a flow rate of 5 mL/min. The column was first washed with buffer A (20 mM Tris (pH 8.0), 500 mM NaCl, 20 mM imidazole, 0.5 mM PMSF), followed by washing, using buffer A and buffer B (20 mM Tris (pH 8.0), The ratio of the imidazole of the solution was adjusted in proportion to 500 mM NaCl, 500 mM imidazole, 0.5 mM PMSF) to wash out the target fusion protein. Since the collected target fusion protein still has other impurity proteins, the fusion protein was isolated using a gel column (HiPrap 26/60S-100). Take

A concentrated centrifuge tube (Millipore) was used to concentrate the protein sample, the protein concentration was adjusted to about 0.5 to 3 mg/mL, and dispensed into a microcentrifuge tube and stored at -80 °C. Protein purity was confirmed by SDS-PAGE analysis as shown in Figure 1.

3. Receptor binding assay

3.1 Target fusion protein binding to Integrin

The binding of EGF, RGD-EGF, NGR-EGF, RGD4C-EGF, VEGF, RGD-VEGF, NGR-VEGF, and RGD4C-VEGF target fusion proteins to cells was analyzed by ELISA cell binding assay. 25 μg/well of integrin (αvβ3) receptor dissolved in PBS (calcium and magnesium ions) was placed in a 96well ELISA microplate, and cultured at 4 ° C for 12 hours, and then reacted with 3% BSA at 25 ° C for 1 hour. The serially diluted target fusion protein was added to culture at 25 ° C for 2 hours, and after washing with PBS buffer (containing calcium and magnesium ions), the mouse anti-His-HRP antibody was used to detect the binding of the protein to the receptor, and the wavelength was measured. The absorbance at 450 nm is used to quantify the amount of protein bound to the receptor. The obtained data using the prism software for nonlinear curve fitting can obtain the dissociation constant K _d value of protein binding, which can be used as a comparison of the binding ability of the protein to different receptors.

3.2 Binding fusion protein binding to EGFR and VEGFR

25 μg/well of anti-IgG antibody dissolved in PBS buffer (calcium, magnesium ion) was placed in a 96well ELISA microplate, and cultured at 4 ° C for 12 hours, and then reacted with 3% BSA at 25 ° C for 1 hour. 25 ng/well EGFR or VEGFR was added and reacted at 25 ° C for 2 hours. After washing with PBS buffer (containing calcium and magnesium ions), serially diluted target fusion proteins were added and incubated at 25 ° C for 2 hours. After washing with PBS buffer (containing calcium and magnesium ions), the mouse anti-His-HRP antibody was used to detect binding of the protein to the receptor, and the absorbance at a wavelength of 450 nm was measured to quantify the amount of protein bound to the receptor. The obtained data using the prism software for nonlinear curve fitting can obtain the dissociation constant Kd value of protein binding, which can be used as a comparison of the binding ability of the protein to different receptors.

The dissociation constant K _d values of EGF, RGD-EGF, RGD4C-EGF and EGFR were 2.38, 20.35 and 14.33 nM, respectively. The dissociation constant K _d values of VEGF, RGD-VEGF, RGD4C-VEGF and Integrin were 0, 5.0 and 1.0, respectively. VEGF, RGD-VEGF, VEGFR1 solution RGD4C-VEGF with a dissociation constant K _d values of 15.3,11.3 and 11.4. The dissociation constant K _d values of VEGF, RGD-VEGF, RGD4C-VEGF and VEGFR2 were 22.2, 12.1 and 13.9, respectively.

Referring to Figures 2A-2F, various dual-target fusion proteins can bind to more than two receptors, with the ability to dual target. RGD-EGF and RGD4C-EGF can bind to Integrin (αvβ3) and EGFR, respectively, and RGD-VEGF and RGD4C-VEGF can bind to Integrin (αvβ3), VEGFR1 and VEGFR2, respectively.

4. Cell binding assay

This example uses MDA-MB468 (highly expressed EGFR), MDA-MB231 (moderately expressed EGFR), MCF-7 (low performance), HT1080 (expressed APN), U87MG (expressed αvβ3) and HUVEC (expressed VEGFR and αvβ3) Cell lines to analyze the specific binding of the dual-target fusion protein to different receptors.

MDA-MB468, MDA-MB231, MCF-7, HT1080, U87MG and HUVEC cells were seeded in a 96-well microplate at a dose of 20,000 cells/well, and cultured at 37 ° C for 12 hours. After the cells were attached, they were fixed with 4% paraformaldehyde hyde precooled at 4 ° C, and then incubated at room temperature for 15 minutes. After the fixed cells were incubated with 3% FBS at 25 ° C for 1 hour, serially diluted target fusion proteins were added and incubated at 25 ° C for 1 hour. After washing with PBS buffer (containing 1 mmol/L CaCl ₂ and 0.5 mmol/L MgCl ₂ ), the mouse anti-His-HRP antibody was used to detect the binding of the protein to the cells, and then the TMP of the HRP was used for color measurement. The absorbance at a wavelength of 450 nm to quantify the amount of protein bound to the cells. The data obtained using prism software for non-linear curve fitting (curve fitting) available binding protein dissociation constant K _d value.

EGF, RGD-EGF, EGFR solution on RGD4C-EGF with the MDA MB 468 cell dissociation constant K _d values of 16.38,26.97 and 22.22nM. VEGF, RGD-VEGF, RGD4C- VEGF, NGR-VEGF and decompression intergrin U87MG cells on the dissociation constant K _d values of 1.74,1.83,1.9 and 1.9μM. VEGF, RGD-VEGF, RGD4C- VEGF, NGR-VEGF and VEGFR intergrin solution on HUVEC cells with a dissociation constant K _d values of 12.7,11.9,6.4 and 9.4nM.

Referring to Figures 3A-3D, RGD-EGF, RGD4C-EGF, RGD-VEGF, and RGD4C-VEGF can bind to cells expressing the corresponding receptor.

Competitive binding assays were performed in U87MG and HUVEC cells with RGD peptide or VEGFR antibody and RGD-VEGF and RGD4C-VEGF. The addition of the competitor can effectively reduce the binding of RGD-VEGF and RGD4C-VEGF to cells. As a result, it was confirmed that the dual target molecule of the present invention can specifically bind to the biomarker of the tumor.

5. Cell adhesion test

This example uses an ECM cell adhesion analysis system to analyze the adhesion characteristics of cells. Different concentrations of the target fusion protein were coated per well in a 96-well microplate and incubated at 16 ° C for 12 hours. After the protein was attached, 3% BSA was added and incubated at 25 ° C for 1 hour. Tumor cells (U87MG, ⁵ ×10 ⁵ cells/well) that had been starved for one hour were added to a 96-well microplate, and after incubation at 37 ° C for 2 hours, they were washed with D-PBS to remove cells not bound to the protein. Finally, MTT was added and incubated at 37 ° C for 1 hour. The surviving cells metabolized the MTT agent to formazan blue-violet crystals. The wax was dissolved in DMSO to detect the absorbance at a wavelength of 570 nm. The cell attachment characteristics were calculated by the following formula.

Cell attachment (%) = (test group OD value / control group OD value) × 100%

Referring to Figures 4A-D, RGD-VEGF and RGD4C-VEGF were applied to the cell disk After that, the number of U87MG cells and HUVEC cells attached to the culture plate can be increased, and if a large amount of RGD peptide chain is added to compete, the adsorption of cells can be reduced. Figure 4A shows that RGD-VEGF and RGD4C-VEGF are coated on the cell plate to increase the amount of U87MG cells attached to the culture plate, while Figure 4B shows the amount of cells attached to the plate after the addition of the RGDfV polypeptide. Inhibition, Figure 4C-4D shows that RGD-VEGF and RGD4C-VEGF bind to HUVEC cells, and then compete with RGDfV polypeptide or VEGFR2 recombinant protein, respectively, in terms of absorbance and percentage.

6. Cell activation test

In a cellular assay, the fusion protein activates the cellular receptor and its downstream signaling molecule phosphorylation. Various human tumor cells were cultured with 25nM target fusion protein at 37 ° C for 60 minutes to collect intracellular protein extracts, and the phosphorylation reaction of cell receptors and their downstream signal molecules was analyzed by Western blotting method.

Referring to Figure 5, RGD-EGF and RGD4C-EGF were co-cultured with MDA-MB468 cells expressing EGFR; or RGD-VEGF and RGD4C-VEGF were co-cultured with HUVEC vascular endothelial cells expressing VEGFR1 and VEGFR2. The signaling molecules downstream of EGFR (Fig. 5A) or VEGFR (Fig. 5B) were analyzed. RGD-EGF and RGD4C-EGF or RGD-VEGF and RGD4C-VEGF can activate the signaling pathway downstream of EGFR or VEGFR, respectively. The results show that the double target molecule of the present invention not only has the ability to bind to a relatively biomarker molecule, but a large peptide molecule such as EGF or VEGF retains its original biological properties.

7. Preparation of radioactive marker target fusion protein

2-(4-Iso thiocyanatobenzyl-diethylenetriaminepentaacetic acid, p-SCN-Bn-DTPA) is dissolved in HEPES buffer solution, and RGD-EGF is added. The target fusion protein (fusion protein: p-SCN-Bn-DTPA = 1:5 to 20 (molar ratio)) such as RGD4C-EGF was reacted at room temperature for 1 hour. The unreacted small molecule reactant was removed by colloidal chromatography (Sephadax G25) to obtain a radioactive marker precursor protein such as DTPA-RGD-EGF and DTPA-RGD4C-EGF. An appropriate amount of HEPES buffer solution and radioactive ( ¹¹¹ InCl ₃ , ⁶⁷ GaCl ₃ , ⁹⁰ YCl ₃ and ¹⁷⁷ LuCl _{3 ,} etc.) were added to the above-mentioned fusion protein solution bound to DTPA, and reacted at room temperature for 1 hour. Excess EDTA was added to chelate the radioactive metal ions not bound to the protein, and purified by membrane filtration centrifugation and colloidal chromatography. The activity was measured and the radiochemical purity of the product was analyzed by radioactive thin layer analysis. The stability of the fusion protein in buffer solution (HEPES, 4 ° C) and serum (37 ° C). Referring to Figure 6, the stability of ¹¹¹ In-DTPA-RGD4C-EGF over time in Hepes buffer (4 ° C) and fetal bovine serum (37 ° C). The three (the original radiochemical purity were greater than 95%) were stored in Hepes buffer (4 ° C) and fetal bovine serum (37 ° C), and the radiochemical purity was still higher than 90% after 24 hours.

8. Cell fluorescence photography experiment

Tumor cells or vascular cells (2.5× ^{10 5} cells/well) were cultured in a 12-well cell culture dish at 37 ° C for one day in a CO ₂ incubator. The medium in the culture plate was removed, and the cells were washed with 1 mL of PBS, and then VEGF, RGD-VEGF and RGD4C-VEGF were separately added, and the cells were allowed to stand at 37 ° C for 2 hours in a CO ₂ incubator. After the medium was removed, it was washed three times with 0.5 mL of PBS, and after adding an anti-His ₆ fluorescent-labeled antibody, the image was directly observed with a fluorescence microscope. Referring to Figure 7, fluorescent photography revealed that RGD-VEGF and RGD4C-VEGF marker recombinant protein can bind to cells.

9. Single photon and computed tomography (SPECT/CT) angiography of radioactive marker recombinant protein

Tumor mice (tumor size about 50-100 mm ³ ) were injected with 500 μCi of radiolabeled recombinant protein in the tail vein, respectively. Small animal SPECT/CT angiography was performed at 1, 2, 4, 8, 24, 48 and 72 hours after the injection. After the end of the angiography, the image was processed by software, and the tumor to muscle ratio was calculated by ROI (region of interest) analysis to evaluate the dynamic accumulation of the drug in the living body of the animal. Refer to Figure 8. U87MG subcutaneous tumor mice were injected with ¹¹¹ In-DTPA-EGF, ¹¹¹ In-DTPA-RGD-EGF and ¹¹¹ In-DTPA-RGD4C-EGF in the tail vein for 1, 4, 8 and 24 hours. Computed tomography (SPECT/CT) angiography. The image shows that after the In-111 marker recombinant protein is applied, the specific accumulation of the tumor in the tumor (expressed as the tumor/muscle accumulation ratio) increases with time, reaching a peak at 8 hours after the drug injection, at this time ¹¹¹ In The tumor/muscle accumulation ratio of -DTPA-RGD4C-EGF was 4.4, slightly higher than 3.6 of ¹¹¹ In-DTPA-RGD-EGF, and much higher than 1.7 of ¹¹¹ In-DTPA-EGF.

Quantitative analysis of tumor specific accumulation showed that RGD4C-EGF and RGD-EGF fusion proteins have dual targeting ability, and the accumulation of tumors is significantly higher than that of EGF recombinant protein with only single target ability; The sequence of RGD4C-EGF fusion protein has better binding ability to integrinαvβ3, which makes it accumulate in tumors slightly better than RGD-EGF fusion protein with linear RGD sequence.

The technical features of the invention disclosed in all of the specification can be combined in any manner. Each of the technical features disclosed in the specification may be replaced by other means that provide the same, equivalent or similar purpose. Therefore, unless otherwise stated, all the features disclosed herein are An example of a general series of equivalent or similar features.

It will be apparent to those skilled in the art that <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt;

Claims

A dual target drug carrier characterized by comprising a first target molecule and a second target molecule.
The dual target pharmaceutical carrier according to claim 1, wherein the first and second target molecules are peptides or proteins.
The dual target pharmaceutical carrier according to claim 1, wherein the first or second target molecule specifically binds to vascular endothelial cells in tumor cells or/and tumor microenvironments.
The dual target drug carrier according to claim 1, wherein the first and second target molecules include, but are not limited to, arginine-glycine-aspartate (RGD), asparagine - glycine-arginine (NGR), cyclic NGR, internalization RGD (iRGD), cystine-glycine-aspartate-lysine-arginine-threonine-arginine-glycine - Alanine (CGNKRTRGA), gastrin, bombesin, octreotide or a derivative thereof.
The dual target drug carrier according to claim 1, wherein the first and second target molecules include, but are not limited to, epidermal growth factor (EGF), anti-EGFR antibody, vascular endothelial growth factor ( VEGF), anti-VEGFR antibody, anti-HER2 antibody, hepatocyte growth factor receptor (HGFR), anti-HGFR antibody, tumor necrosis factor (TNF) or anti-TNF antibody.
The dual target drug carrier of claim 1 wherein said first target molecule is linked to said second target molecule by a linker.
The dual target pharmaceutical carrier according to claim 5, wherein the connector is a peptide having 5 to 20 amino acids.
The dual target pharmaceutical carrier of claim 5, wherein the connector comprises, but is not limited to, GG, PGGGG or GGGGSGGGGS.
A radioactive target marker protein, characterized in that the radioactive target marker protein consists of the dual target drug carrier of claim 1 and a radioactive nucleus.
The radiolabeled marker protein according to claim 8, wherein the dual target drug carrier is linked to the radioactive nucleus by a metal chelating agent.
The radioactive target marker protein according to claim 9, wherein the metal chelating agent is composed of DTPA (diethylene triamine pentaacetic acid) and NOTA (1,4,7-triazacyclocycle). Decane, 1,4,7-triazacyclononane-N, N', N"-triacetic acid) or DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-four Acetic acid, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) One or more of a group of various metal chelators and various derivatives thereof.