KR101907251B1 - Biomarker for diagnosis and treatment of antiestrogen-resistant or triple negative breast cancer and composition comprising the same - Google Patents

Abstract

The present invention relates to a novel biomarker for diagnosis and treatment of antihormonal resistance and triple-negative breast cancer, and a composition comprising the same. More particularly, the present invention relates to a novel biomarker and a composition comprising the same, Hormone therapy in anti-hormone-refractory breast cancer including triple-negative breast cancer by allowing the effective diagnosis of anti-hormone and triple-negative breast cancer and further increasing expression of Mel-18 gene or administration of Mel-18 protein The present invention can provide a pharmaceutical composition capable of dramatically improving the therapeutic efficacy of the present invention.

Description

TECHNICAL FIELD The present invention relates to a biomarker for diagnosis and treatment of antihormonal and triple-negative breast cancer, and a composition comprising the biomarker and an antiestrogen-resistant or triple negative breast cancer.

The present invention relates to a novel biomarker for diagnosing and treating antihormonal and triple-negative breast cancer and a composition comprising the same.

The estrogen receptor (ER) -a, a hormone-dependent nuclear receptor encoded by ESR1, is the most common clinical marker used to classify breast cancer prognosis and breast cancer subtypes. Approximately 30% of breast cancers do not express ER-α, which is associated with an aggressive phenotype resistant to anti-estrogen therapy, and a poor prognosis (Ali S, and Coombes RC. significance J Mammary Gland Biol Neoplasia 2000; 5 (3): 271-81).

In these ER-α-negative cells, expression of ER-α and progesterone receptors (encoded by PR, PGR) and triple-negative breast cancer (TNBC ) Are not therapeutically effective from conventional hormone and HER2-based therapies, and the molecular mechanisms of TNBC are poorly understood. Since ESR1 expression can be reversibly regulated by several epigenetic factors including histidine modification and DNA methylation (Giacinti L, Claudio PP, Lopez M, and Giordano A. Epigenetic information and estrogen receptor alpha expression in breast Keen JC, Yan L, Mack KM, Pettit C, Smith D, Sharma D, and Davidson NE. A novel histone deacetylase inhibitor, scriptaid, enhances expression of functional estrogen (3): 177-86; Yang X, Phillips DL, Ferguson AT, and Nelson WG. , Herman JG, and Davidson NE. Synergistic activation of functional estrogen receptor (ER) -alpha by DNA methyltransferase and histone deacetylase inhibition in human ER-alpha-negative breast cancer cells. Cancer Res 2001; 61 (19): 7025-9 ), ER-alpha recurrence using demethylated or deacetylated agents It has restored the sensitivity of breast cancer and ER-α- voice TNBC on the dock line therapy and Performing bars (Peddi PF, Ellis MJ, and Ma C. Molecular basis of triple negative breast cancer and implications for therapy. International journal of breast cancer. 2012 (217185)). However, until now, the mechanisms of ER-alpha loss and regulation of ESR1 gene transcription in breast cancer have not been fully understood.

MEL-18 is a component of the polycomb inhibitory complex (PRC) -1, a crucial regulator of stem cell regulation and normal and cancer cell development (Sauvageau M, and Sauvageau G. Polycomb group proteins: multi -faceted regulators of somatic stem cells and cancer. Cell Stem Cell. 2010; 7 (3): 299-313). Although additional clinical evidence is needed, accumulated evidence suggests that MEL-18 acts as a tumor suppressor in some human tumors, including breast cancer (Guo WJ, Zeng MS, Yadav A, Song LB, Guo BH, 2007, 67 (11): 5083-9; Wang W, Yuasa (2007), "B-1 expression and down-regulating Akt activity in breast cancer cells. T, Tsuchiya N, Ma Z, Maita S, Narita S, Kumazawa T, Inoue T, Tsuruta H, Horikawa Y, et al. Expression of BMI-1 and Mel-18 in breast tissue-a (RI) ML, Luders T, Nesbakken AJ, Vollan HS, Kristensen V, and Bukholm IR Diagnostic marker in patients with breast cancer. BMC cancer 2010. 10 (686); Guo BH, Zhang X, Zhang HZ, Lin HL, Feng Y, Shao JY, Huang WL, Kung HF, and Zeng MS. Sion of Mel-18 predicts poor prognosis in patients with breast cancer. Annals of oncology: Official journal of the European Society for Medical Oncology / ESMO. 2010; 21 (12): 2361-9; Zhang XW, Sheng YP, Li Q, Qin W, Lu YW, Cheng YF, Liu BY, Zhang FC, Li J, Dimri GP, et al. BMI1 and Mel-18 oppositely regulate carcinogenesis and progression of gastric cancer. Molecular cancer. 2010; 9 (40).

We also found that MEL-18 loss promotes stem cell activity, cell growth, angiogenesis, and epithelial-filament mutation (EMT) in breast cancer (12-15) (Won HY, Lee JY, Shin DH, Park JH, Nam JS, Kim HC, and Kong G. Loss of Mel-18 enhances breast cancer stem cell activity and tumorigenicity through activating Notch signaling mediated by the Wnt / TCF pathway. FASEB J. 2012; 26 (12): 5002-13; Park JH, Lee JY, Shin DH, Jang KS, Kim HJ, and Kong G. Loss of Mel-18 inducing tumor angiogenesis through enhancing the activity and Expression of HIF-1alpha mediated by the PTEN / PI3K / Akt pathway. Oncogene. 2011; 30 (45): 4578-89; Lee JY, Jang KS, Shin DH, Oh MY, Kim HJ, Kim Y and Kong G. Mel-18 negatively regulates INK4a / ARF-independent cell cycle progression via Akt inactivation in breast cancer. Cancer Res 2008; 68 (11): 4201-9; Lee JY, Park MK, Park JH, Lee HJ, Y, Lee CH, and Kong G. Loss of the polycomb protein Mel-18 enhances the epithelial-mesenchymal transition by ZEB1 and ZEB2 expression through the downregulation of miR-205 in breast cancer. Oncogene. 2014; 33 (10): 1325-35).

MEL-18 is involved in a number of post-translational modifications of the target protein and subsequent gene regulation. PRC-1, which contains ubiquitin E3 ligase RING1B, regulates both histone H2A ubiquitination-mediated gene silencing and ubiquitin-proteasome-mediated proteolysis. The present inventors have also demonstrated that MEL-18 negatively regulates RING1B activity by inhibiting BMI-1 transcription (Qian T, Lee JY, Park JH, Kim HJ, and Kong G. Id1 enhances RING1b E3 ubiquitin ligase activity through the Mel-18 / Bmi-1 polycomb group complex. Oncogene. 2010; 29 (43): 5818-27). In addition, MEL-18 is also known to act as an inhibitor of sumoylation (Zhang J, Goodson ML, Hong Y, and Sarge KD. MEL-18 interacts with HSF2 and the SUMO E2 UBC9 to inhibit HSF2 sumoylation. 2008; 375 (2): 252-5). In this study, we investigated the effect of the enzyme on the activity of RanGAP1 and inhibit its sumoylation. Biochemical and biophysical research communications. 2008; 37 (2): 252-5) , The importance of MEL-18 in sumoization remains unclear to this day.

Therefore, in any of the prior arts, there has been no report on the relationship between anti-hormone-resistant breast cancer including Mel-18 and triple-negative breast cancer. Furthermore, Mel-18 has been used to improve the therapeutic efficacy of conventional breast cancer No one has ever been reported.

Therefore, the present invention aims to provide Mel-18 gene and protein as a biomarker for the effective diagnosis of antihormonal resistance and triple-negative breast cancer, and further, to increase the expression thereof, And to dramatically increase the therapeutic efficacy.

In order to solve the above problems of the present invention,

There is provided a composition for the diagnosis of breast cancer comprising mRNA of the Mel-18 gene or an agent for measuring the degree of expression of the protein.

Preferably, the mRNA of the Mel-18 gene may be a nucleic acid sequence represented by SEQ ID NO: 1.

1 atgcatcgga ctacacggat caaaatcaca gagctgaacc cccacctcat gtgtgccctc

61 tgcggggggt acttcatcga cgccaccact atcgtggagt gcctgcattc cttctgcaaa

121 acctgcatcg tgcgctacct ggagaccaac aaatactgcc ccatgtgtga cgtgcaggtc

181 cataaaaccc ggccgctgct gagcatcagg tctgacaaaa cacttcaaga cattgtctac

241 aaattggtcc ctgggctttt taaagatgag atgaaacggc ggcgggattt ctatgcagcg

301 taccccctga cggaggtccc caacggctcc aatgaggacc gcggcgaggt cttggagcag

361 gagaaggggg ctctgagtga tgatgagatt gtcagcctct ccatcgaatt ctacgaaggt

421 gccagggacc gggacgagaa gaagggcccc ctggagaatg gggatgggga caaagagaaa

481 acaggggtgc gcttcctgcg atgcccagca gccatgaccg tcatgcatct tgccaagttt

541 ctccgcaaca agatggatgt gcccagcaag tacaaggtgg aggttctgta cgaggacgag

601 ccactgaagg aatactacac cctcatggac atcgcctaca tctacccctg gcggcggaac

661 gggcctctcc ccctcaagta ccgtgtccag ccagcctgca agcggctcac cctagccacg

721 gtgcccaccc cctccgaggg caccaacacc agcggggcgt ccgagtgtga gtcagtcagc

781 gacaaggctc ccagccctgc caccctgcca gccacctcct cctccctgcc cagcccagcc

841 accccatccc atggctctcc cagttcccat gggcctccag ccacccaccc tacctccccc

901 actccccctt cgacagccag tggggccacc acagctgcca acgggggtag cttgaactgc

961 ctgcagacac catcctccac cagcaggggg cgcaagatga ctgtcaacgg cgctcccgtg

1021 ccccccttaa cttga

Preferably, the Mel-18 protein may be an amino acid sequence represented by SEQ ID NO: 2.

1 mhrttrikit elnphlmcal cggyfidatt iveclhsfck tcivryletn kycpmcdvqv

61 hktrpllsir sdktlqdivy klvpglfkde mkrrrdfyaa ypltevpngs nedrgevleq

121 ekgalsddei vslsiefyeg ardrdekkgp lengdgdkek tgvrflrcpa amtvmhlakf

181 lrnkmdvpsk ykvevlyede plkeyytlmd iayiypwrrn gplplkyrvq packrltlat

241 vptpsegtnt sgasecesvs dkapspatlp atssslpspa tpshgspssh gppathptsp

301 tppstasgat taanggslnc lqtpsstsrg rkmtvngapv pplt

Preferably, the agent for measuring the mRNA of the Mel-18 gene or the expression level of the protein is an antibody specific to the Mel-18 protein.

Preferably, the antibody may be a monoclonal antibody or a polyclonal antibody specific for the Mel-18 protein.

Preferably, the agent for measuring the mRNA expression level of the Mel-18 gene may be an antisense oligonucleotide complementary to the mRNA of the RORC gene, a primer or a probe.

Meanwhile, the present invention provides a kit for diagnosing antihormonal and triple-negative breast cancer, which comprises the above composition.

Further, the present invention provides a diagnostic or prognostic assay for antihormonal and triple-negative breast cancer, comprising the step of detecting the mRNA of the Mel-18 gene or a protein thereof from a patient sample to provide information necessary for diagnosis of breast cancer. A method for detecting a marker for use is provided.

Preferably, the sample may be one or more samples selected from the group consisting of a patient's tissues, cells, blood, serum, plasma saliva, and urine.

Preferably, the method comprises the steps of measuring the expression level of mRNA of the Mel-18 gene or the protein thereof from a sample of a patient, and measuring the expression level of the mRNA of the Mel-18 gene or the protein thereof in a normal control sample, 18 gene mRNA or the degree of expression of the protein.

Preferably, the expression level of the mRNA of the Mel-18 gene is measured by a reverse transcriptase polymerase, a competitive reverse transcriptase polymerase, a real-time reverse transcriptase polymerase, an RNase protection assay, a Northern blotting or a DNA chip .

Preferably, the method for measuring the degree of expression of the Mel-18 protein includes Western blotting, ELISA, radioimmunoassay, radial immunodiffusion, Oucheronian immunodiffusion, rocket immunoelectrophoresis, tissue immuno staining, Complement fixation assay, FACS or protein chip.

Meanwhile, the present invention provides a pharmaceutical composition for treating breast cancer, comprising a component for increasing mRNA expression of Mel-18, or a Mel-18 protein as an active ingredient.

According to a preferred embodiment of the present invention, the anti-hormonal therapeutic agent is selected from the group consisting of tamoxifen, raloxifene (Evista), toremifene (Fareston) And so on.

Further, the pharmaceutical composition is effective for treatment of Mel-18 disappearance antihormone-resistant breast cancer when an anti-hormone therapeutic agent and a PI3K inhibitor such as BKM120 are administered together. The pharmaceutical composition further includes a PI3K inhibitor together with an anti-hormone therapeutic agent for the treatment of breast cancer can do.

Hereinafter, the present invention will be described in more detail.

The present invention is based on the fact that the expression level of the Mel-18 gene mRNA or its protein is decreased in patients with anti-hormone and triple-negative breast cancer, , We were able to more accurately and effectively diagnose or prognose patients with antihormonal and triple-negative breast cancer. Furthermore, a pharmaceutical composition capable of treating antihormonal resistance and triple-negative breast cancer of the patient by artificially increasing Mel-18 mRNA expression or administering Mel-18 protein in such a breast cancer patient is provided .

Conventionally, there has been no study on the functional effect of the polycomb protein, MEL-18, on the hormone regulation of breast cancer. In the present invention, we have shown that MEL-18 loss contributes to the hormone-independent phenotype of breast cancer by regulating hormone receptor expression, and it has also been shown that MEL-18 is downregulated in a triple-negative breast cancer population .

As can be seen in the following examples, MEL-18 expression was positively correlated with the expression of Luminal markers including the estrogen receptor (ER) -α (encoded by ESR1) -α-positive breast cancers inhibit the effect of anti-hormone therapy. In addition, MEL-18 loss in LUMINARY breast cancer caused downregulation of expression and activity of ER-α and progesterone receptor (PR), but MEL-18 overexpression restored ER-α expression in TNBC. On the other hand, in vivo xenotransplantation experiments have shown that MEL-18 loss induces estrogen-independent growth and tamoxifen resistance in LUMINARY breast cancer, and MEL-18 overexpression confers tamoxifen sensitivity in TNBC. In that pathway, MEL-18 is thought to promote ESR1 expression by inhibiting the sumoylation of p53 and SP1, the ESR1 transactivation factors, and inhibits the BMI-1 / RING1B-mediated ubiquitin-proteasome degradation of SENP1 De-sumoylation process. Taken together, these data suggest that MEL-18, a SUMO-dependent modulator of hormone receptors, plays an important role in determining anti-hormone therapy response.

For purposes of the present invention, the term "diagnosis" refers to identifying the presence or characteristic of a pathologic condition, and for purposes of the present invention, the diagnosis is to identify antihormonal and triple-negative breast cancer in a patient. Specifically, it may be possible to identify antihormonal resistance and triple-negative breast cancer by confirming whether the expression of Mel-18 mRNA or protein thereof in the patient's sample is inhibited as compared with the normal control.

In the present invention, the term "measurement of mRNA expression level of Mel-18 gene" refers to the presence or absence of mRNA and expression level of Mel-18 gene from a biological sample in order to diagnose antihormonal resistance and triple- , And measuring the amount of mRNA of the Mel-18 gene. RT-PCR (Real-time RT-PCR), RNase protection assay (RPA; RNaseprotection assay), RT-PCR (Competitive RT-PCR) , Northern blotting, and DNA chips. However, the present invention is not limited thereto.

The agent for measuring the degree of mRNA expression of the Mel-18 gene means a substance that can be used for detecting the mRNA of the Mel-18 gene in a sample of a patient. For example, it may be a primer, a probe, an antisense oligonucleotide, or the like which can complementarily bind to the mRNA of the Mel-18 gene. Preferably, the antisense nucleotide, primer or probe specifically binds to the mRNA sequence of the Mel-18 gene and does not specifically bind to the base sequence of the other nucleic acid material.

Herein, complementary binding means that the antisense oligonucleotide is sufficiently complementary to hybridize selectively to the mRNA target of the Mel-18 gene under a predetermined hybridization or annealing condition, preferably physiological condition, Substantially " means substantially including both substantially complementary and perfectly complementary, and preferably means completely complementary.

For example, the agent used to detect the mRNA biomarker of the Mel-18 gene of the present invention may be an antisense oligonucleotide. The term "antisense oligonucleotide" refers to a nucleic acid-based molecule capable of forming a duplex with the mRNA of the Mel-18 gene, having a complementary sequence to the mRNA sequence of the target Mel-18 gene, Lt; RTI ID = 0.0 > mRNA < / RTI >

As another example, the agent used to detect the mRNA biomarker of the Mel-18 gene of the present invention is a primer pair or a probe, and since the base sequence of the Mel-18 gene is known, A primer or a probe that specifically amplifies a specific region of these genes can be designed.

The term "primer" refers to a nucleic acid sequence having a short free 3 'hydroxyl group, capable of forming a base pair with a complementary template and serving as a starting point for template strand copying Quot; refers to 7 to 50 nucleic acid sequences which function. Primers are usually synthesized but can also be used in naturally occurring nucleic acids. The sequence of the primer does not necessarily have to be exactly the same as the sequence of the template, but is sufficiently complementary that it can hybridize with the template. Primers can be used to initiate DNA synthesis in the presence of a polymerization reaction (i.e., a reagent for DNA polymerase or reverse transcriptase, and four different nucleoside triphosphates) at the appropriate buffer solution and temperature In the present invention, triple-negative breast cancer can be diagnosed by performing PCR amplification using a sense of Mel-18 base sequence and an antisense primer. PCR conditions, length of sense and antisense primer May be modified based on those known in the art. Preferably, the primer of the present invention may be a primer capable of amplifying the mRNA of the Mel-18 gene.

In another example, the agent used to detect the mRNA biomarker of the Mel-18 gene of the present invention may be a probe. The term "probe" means a nucleic acid fragment such as RNA or DNA corresponding to a short period of a few nucleotides or a few hundred nucleotides that can specifically bind to mRNA, and is labeled to confirm the presence or absence of a specific mRNA . The probe may be prepared in the form of an oligonucleotide probe, a single stranded DNA probe, a double stranded DNA probe, or an RNA probe. In the present invention, hybridization using a probe complementary to Mel-18 polynucleotide can be used to diagnose triple-negative breast cancer through hybridization. Selection of suitable probes and hybridization conditions can be modified based on what is known in the art.

The primers or probes of the present invention can be chemically synthesized using a phosphoramidite solid support method, or other well-known methods. Such nucleic acid sequences may incorporate additional features that do not alter the basic properties. Examples of additional features that may be incorporated include, but are not limited to, methylation, capping, substitution of one or more nucleic acids with homologues, and modification between nucleic acids.

The agent that measures Mel-18 protein levels herein is preferably an antibody. "Antibody" means a specific protein molecule, as is known in the art, directed against an antigenic site. For purposes of the present invention, an antibody refers to an antibody that specifically binds to a Mel-18 protein, which is a marker of the present invention. Such an antibody may be obtained by cloning Mel-18 gene into an expression vector according to a conventional method, To obtain a Mel-18 protein which is encoded by the Mel-18 gene, and can be prepared from the obtained Mel-18 protein by a conventional method. Also included are partial peptides that can be made from the Mel-18 protein, and the partial peptides of the invention include at least 7 amino acids, preferably 9 amino acids, more preferably 12 amino acids.

The form of the antibody of the present invention is not particularly limited, and a polyclonal antibody, a monoclonal antibody or a part thereof having antigen binding ability is included in the antibody of the present invention and includes all immunoglobulin antibodies. Furthermore, the antibodies of the present invention include special antibodies such as humanized antibodies. Antibodies used in the detection of the triple-negative breast cancer diagnostic markers of the invention include full forms having two full-length light chains and two full-length heavy chains, as well as functional fragments of antibody molecules . A functional fragment of an antibody molecule refers to a fragment having at least an antigen-binding function, and includes Fab, F (ab ') 2, F (ab') 2 and Fv.

In addition, in the present invention, antihormone-resistant and triple-negative mammary cancer diagnostic compositions comprising the agent for measuring the expression level of the mRNA of the Mel-18 gene or its protein may be provided in the form of a kit.

The kit of the present invention can confirm the expression level of mRNA or Mel-18 protein of Mel-18 gene which is an anti-hormone resistance and triple-negative breast cancer diagnostic marker. The kit of the present invention may include one or more kinds of antibodies suitable for the analysis method as well as antibodies recognizing primers, probes, antisense oligonucleotides or optionally Mel-18 protein for measuring the expression level of the Mel-18 gene mRNA or Mel-18 protein Further, other component compositions, solutions or devices may be included.

As a specific example, a kit for measuring the mRNA expression level of the Mel-18 gene in the present invention may be a kit containing essential elements necessary for performing RT-PCR. The RT-PCR kit contains test tubes or other appropriate containers, reaction buffers (varying in pH and magnesium concentration), deoxynucleotides (dNTPs), Taq Enzymes such as polymerase and reverse transcriptase, DNase, RNAse inhibitors, DEPC-water, sterile water, and the like. It may also contain a primer pair specific to the gene used as a quantitative control. Also preferably, the kit of the present invention may be a diagnostic kit containing essential elements necessary for performing a DNA chip. The DNA chip kit may include a substrate on which a cDNA corresponding to a gene or a fragment thereof is attached as a probe, a reagent for preparing a fluorescent-labeled probe, a preparation, an enzyme, and the like. In addition, the substrate may contain a cDNA corresponding to a quantitative control gene or a fragment thereof.

As another specific example, the kit for measuring the degree of expression of Mel-18 protein in the present invention may be used for the immunological detection of antibody, a substrate, a suitable buffer solution, a secondary antibody labeled with a chromogenic enzyme or a fluorescent substance, . ≪ / RTI > The substrate may be a nitrocellulose membrane, a 96-well plate synthesized from polyvinyl resin, a 96-well plate synthesized from polystyrene resin, a slide glass made of glass, etc. The chromogenic enzyme may be peroxidase, Alkaline Phosphatase may be used as the fluorescent substance, FITC, RITC or the like may be used as the fluorescent substance, and ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) ) Or OPD (o-phenylenediamine), TMB (tetramethylbenzidine) can be used.

In addition, the present invention provides a method for detecting triple-negative breast cancer marker Mel-18 from a patient's sample to provide information necessary for triple-negative breast cancer diagnosis.

More specifically, the degree of expression of the Mel-18 gene can be detected at the mRNA level or the protein level, and the mRNA or protein can be isolated from the patient's sample using a known process.

In the present invention, the term "patient sample" includes samples such as tissues, cells, blood, serum, plasma, saliva, or urine which differ in the expression level of Mel-18, a marker gene of triplet-negative breast cancer. But is not limited to.

Through the above detection methods, the degree of expression of Mel-18 in patients with suspected triple-negative breast cancer can be compared with the level of expression of Mel-18 in the normal control group to diagnose the actual triple-negative breast cancer in the patient. The expression level of Mel-18 in the triple-negative breast cancer patients was measured and the level of Mel-18 expression in the normal control group was measured. The expression level of Mel-18 was triplicated - Less expression in patients who are presumed to be negative breast cancer may be able to diagnose the patient as triple-negative breast cancer.

RT-PCR, RNase protection assay, northern blotting, and DNA chip are examples of analytical methods for measuring the mRNA expression level of the Mel-18 gene, But is not limited thereto. Through these detection methods, it is possible to compare the degree of mRNA expression of the Mel-18 gene in the normal control group and the mRNA expression level of the Mel-18 gene in the triple-negative breast cancer suspect patient, and the expression of the Mel-18 gene in mRNA And the presence of triple-negative breast cancer can be diagnosed in patients with suspected triple-negative breast cancer.

Measurement of the mRNA expression level of the Mel-18 gene is preferably performed using a reverse transcriptase polymerase reaction method or a DNA chip using a primer specific to the mRNA of the Mel-18 gene, which is a triple-negative breast cancer marker.

The above reverse transcriptase-polymerase (RT-PCR) reaction was followed by electrophoresis to identify the band pattern and the band thickness, thereby confirming the expression and degree of the mRNA of the Mel-18 gene and comparing it with the control group. Can be diagnosed easily.

Analysis methods for measuring protein levels include Western blotting, ELISA, radioimmunoassay, radial immunodiffusion, Oucheroton immunodiffusion, rocket immunoelectrophoresis, tissue immuno staining, immunoprecipitation assay, complement fixation assay, FACS, Protein chips, and the like. Through these analytical methods, it is possible to compare the amount of antigen-antibody complex formed in the normal control group with the amount of antigen-antibody complex formed in the triple-negative breast cancer suspect patients, and the decrease in the expression amount of Mel-18 protein , And it is possible to diagnose whether a triple-negative breast cancer patient is actually triple-negative breast cancer.

As used herein, the term " antigen-antibody complex "refers to a combination of a triple-negative breast cancer marker Mel-18 protein and an antibody specific thereto, and the amount of the antigen- antibody complex formed is determined by the size of the signal of the detection label Can be measured quantitatively.

Such detection labels may be selected from the group consisting of enzymes, minerals, ligands, emitters, microparticles, redox molecules, and radioisotopes, but are not necessarily limited thereto. When an enzyme is used as the detection label, available enzymes include? -Glucuronidase,? -D-glucosidase,? -D-galactosidase, urease, peroxidase or alkaline phosphatase, acetylcholine Glucoamylase, terazo, glucose oxidase, hexokinase and GDPase, RNase, glucose oxidase and luciferase, phosphofructokutase, phosphoenolpyruvate carboxylase, aspartate aminotransferase, phosphoenolpyruvate decar ≪ / RTI > beta-lactamase, and the like. The minerals include, but are not limited to, fluorescein, isothiocyanate, rhodamine, picoeriterine, picocyanin, allophycocyanin, o-phthaldehyde, fluororescamine and the like. Ligands include, but are not limited to, biotin derivatives. Emitters include, but are not limited to, acridinium esters, luciferin, luciferase, and the like. Fine particles include, but are not limited to, colloidal gold, colored latex, and the like. Redox molecules include ferrocene, ruthenium complex compounds, Biology hydrogen, quinone, Ti ions, Cs ions, diimide, 1,4-benzoquinone, _{hydroquinone, K 4 W (CN) 8} , [Os (bpy) 3] 2 + , [RU (bpy) ₃ ] 2 ⁺ , [MO (CN) ₈ ] 4 ^-, and the like. Radioisotope includes include ^{3 H, 14 C, 32 P} , 35 S, 36 Cl, 51 Cr, 57 Co, 58 Co, 59 Fe, 90 Y, 125 I, 131 I, 186 Re are not limited to .

In one embodiment, the degree of protein expression is measured by ELISA. ELISAs include direct ELISA using labeled antibodies that recognize the antigen attached to the solid support, indirect ELISA using labeled antibodies that recognize the capture antibody in a complex of antibodies recognizing the antigen attached to the solid support, A direct sandwich ELISA using another labeled antibody that recognizes an antigen in the complex of antibody and antigen, a method of reacting with another antibody recognizing an antigen in a complex of an antibody and an antigen attached to a solid support, Indirect sandwich ELISA using a secondary antibody, and various ELISA methods. More preferably, the antibody is attached to a solid support, the sample is reacted, and the labeled antibody recognizing the antigen of the antigen-antibody complex is adhered to produce an enzyme, or an antibody that recognizes the antigen of the antigen-antibody complex Is detected by a sandwich ELISA method in which a labeled secondary antibody is attached and the enzyme is developed. By confirming the degree of complex formation of Mel-18 protein, which is a triple-negative breast cancer marker, and antibody, triple-negative breast cancer can be confirmed.

Preferably, Western blotting with one or more antibodies against the Mel-18 protein is used. The whole protein is separated from the sample, and the protein is separated according to size by electrophoresis, and then transferred to the nitrocellulose membrane to react with the antibody. The amount of Mel-18 protein produced by the expression of the gene can be confirmed by confirming the amount of the antigen-antibody complex produced by using the labeled antibody, thereby confirming whether triple-negative breast cancer is present. This detection method is performed by examining the amount of Mel-18 gene expression in the control group and the amount of expression of the Mel-18 gene in the triple-negative breast cancer suspect patient. The mRNA or protein level of the triple-negative breast cancer gene can be expressed as the absolute (eg, ug / ml) or relative (eg, the relative intensity of the signal) difference of the Mel-18 protein.

Further, preferably, one or more antibodies against the Mel-18 protein are arranged at predetermined positions on the substrate to use a protein chip immobilized at a high density. A method of analyzing a sample using a protein chip is a method of separating a protein from a sample, hybridizing the separated protein with a protein chip to form an antigen-antibody complex, reading the protein, Triple-negative breast cancer can be confirmed.

Meanwhile, the present invention provides a pharmaceutical composition for treating triple-negative breast cancer, which comprises a component for increasing mRNA expression of Mel-18 or a Mel-18 protein as an active ingredient.

In connection with the present invention, it has been found that the anticancer effect is observed when the expression of Mel-18 is artificially increased in patients with triple-negative breast cancer. Therefore, To provide an effective composition.

In the present invention, the term "comprising as an active ingredient" means that the ingredient is contained in an amount necessary or sufficient to realize the desired biological effect. Determination of the amount contained as an active ingredient in an actual application is an amount for treating a subject disease and may be determined in consideration of other non-toxic factors, for example, the disease or condition to be treated, the form of the composition to be administered, The size of the subject, or the severity of the disease or condition, and the like. Those of ordinary skill in the art to which the invention pertains will be able to empirically determine the effective amount of the individual compositions without undue experimentation.

The form of the composition may be variously selected depending on the mode to be administered and includes, for example, a tablet, a pill, a powder, a capsule, a gel, an ointment, a fluid or a suspension, Lt; / RTI > Preferably, the composition can be administered in unit dosage form suitable for single administration of the exact dosage. The composition may also contain a pharmaceutically acceptable carrier or diluent, depending on the desired formulation, as defined by an aqueous-based vehicle commonly used in formulating pharmaceutical compositions for animal or human administration. Examples of such diluents are distilled water, physiological saline, Ringer's solution, glucose solution, and Hank's solution. The pharmaceutical compositions may also include other pharmaceutical agents, pharmaceutical agents, carriers, adjuvants, non-toxic, non-therapeutic, non-immunostabilizing agents, and the like. An effective amount of such a diluent or carrier is an amount effective to obtain a pharmaceutically acceptable formulation in terms of the solubility, biological activity, etc. of the component.

Meanwhile, the pharmaceutical composition according to the present invention can be used for further enhancing the efficacy of existing antihormonal therapeutic agents for the treatment of breast cancer, but is not limited thereto. For example, tamoxifen, raloxifene (Evista), toremifene (Fareston) Can be used to further enhance the therapeutic efficacy of the same antihormonal agent.

In addition, the pharmaceutical composition according to the present invention is effective for treatment of Mel-18 disappearance antihormone resistant breast cancer when the anti-hormone treatment agent and the PI3K inhibitor such as BKM120 are administered together. As shown in FIG.

According to the present invention, it is possible to provide a biomarker for effective diagnosis of triple-negative breast cancer, and further increase the expression thereof, thereby dramatically improving the therapeutic efficacy of hormone therapy in antihormone-resistant breast cancer including triple-negative breast cancer A pharmaceutical composition which can be improved can be provided.

Figure 1 is a series of data showing that the loss of MEL-18 is associated with poor prognosis and TNBC,
Figure 1A plots MEL-18 negative and positive percentages in different breast cancer subtypes. ** P < 0.01 (Fisher project test);
Figure IB is a representative IHC image and histogram showing the correlation between MEL-18 expression and ER-alpha and PR expression in 223 breast tumor samples. Scale bar: 100μm. * P < 0.05, ** P < 0.01 (Fisher project test);
Figure 1C shows the heat map (top) and box plot (bottom) of MEL-18 mRNA levels in different breast cancer subtypes in the open microarray data set of the proposed breast cancer population. The lower and upper portions of the box correspond to the first quartile and the third quartile, the bands in the box represent the 50 th percentile (middle), whiskers have the lowest values within 1.5 times the quadrant range (IQR) And the highest value, and the outliers are all values that exceed the whiskers. The P value was calculated by ANOVA using the pay-wise comparison method. *** P <0.001 compared with Luminal breast cancer (Lum);
Figure 1D is a scatter plot showing the correlation between MEL-18 expression and ESR1 and PGR expression in the GEO data set (Li et al., GSE 19615. ref. r values were calculated through Spearman rank correlation coefficient analysis;
FIG. 1E shows the OS and DFS according to the expression of MEL-18 in 223 cases of human breast cancer (left) and 53 cases of TNBC (right). This data was analyzed using the Kaplan-Meier method with a log-rank test and a Cox regression model. * P < 0.05, ** P < 0.01.31.
Figure 2 is a series of data showing that MEL-1 positively regulates ESR1 and PR expression,
FIG. 2A is a heat map generated from microarray analysis of MCF-7 cells expressing control (shCon) or MEL-18 shRNA (shMEL) showing differential expression of luminal and basal markers between two groups. This Venn diagram shows the number of common genes between the MEL-18 target gene and the PAM3005 gene list (below);
FIG. 2B is a classification of MEL-18 target genes obtained from microarray analysis according to gene function through GO hatching analysis;
Figure 2C shows that MEL-18-silenced (shMEL) or MEL-18-overexpressing (MEL-18) breast cancer cells and control cells (shCon and Con) were cultured in DMEM containing 10% FBS for 48 h, The seafood was immunoblotted using the presented antibodies. Cell lysates above 100 μg were used for immunoblotting to detect ER-α protein expression in TNBC cells. Relative immunoblot band density is presented below each blot. nd is not detected. The black lines in the blots show that the bands were spliced from the same lane on the same gel (below: PR-A, 81 kDa; Above: PR-B, 116 kDa) due to the expression of PR isoforms of different molecular weights. Data represent three independent experiments. (D and E) mRNA levels of ER-α (ESR1) in the proposed stable cell line were verified by qRT PCR. Data represent the mean ± SD of three duplicate measurements. * P < 0.05 compared to control (shCon or Con) based on 2-tailed Student t-test.
Figure 3 is a series of data showing that MEL-18 depletion eliminates ER-alpha-dependent transcriptional activity and induces estrogen-independent tumor growth,
Figures 3A-3C are graphs showing the effect of the EEL luciferase assay (A) and the control and MEL-18-silenced or MEL-18 cells in the presence and absence of E2 (10 nM in MCF-7 cells or 20 nM in MDA- (B and C) of TFF1 (also referred to as pS2) and PR (PGR) expression levels in over-expressing cell lines. The error bars represent the mean ± SD of three duplicate experiments. * P < 0.05 - comparison with control (2-tailed Student t-test);
Figure 3D is a graph showing the effect of MELl-18 knockdown on E2-independent breast tumor growth. Control or MEL-18-silenced MCF-7 cells were implanted in the breast fat layer of NOD / SCID mice ( n = 8) in the absence of E2 treatment. Tumor size was monitored to assess mouse xenograft tumor growth. * P <0.05 (group x days) Based on RM ANOVA from day 0 to the date indicated. P < 0.001 (days; RM ANOVA);
Figure 3E is a graph showing IHC for MEL-18, ER- [alpha] and PR in the proposed sample of three independent xenografted mice. Scale bar: 100μm. Data at D and E are expressed as means ± SEM ( n = 8 and n = 3, respectively, independent experiments). * P <0.05 compared to shCon (2-tailed Student t-test).
Figure 4 is a series of data showing that the loss of MEL-18 induces resistance to anti-estrogen therapy,
FIG. 4A is a graph showing the cell viability after treatment with tamoxifen (Tam) or ethanol (excipient) at the proposed dose (μM) for 5 days through MTT analysis. Data are presented as means ± SD ( n = 3);
Figure 4B is a graph of tamoxifen administered to NOD / SCID mice injected with control or MEL-18-silenced cells after E2 pellet implantation or post-implantation for 4 weeks ( n = 8; mean ± SEM) . The P values for multiple comparisons (4 groups: shCon / E2, shMEL / E2, shCon / E2 + Tam, and shMEL / E2 + Tam) were calculated via Dunnett's T3 test after Welch ANOVA. ** P = 0.004 for shCon / E2 + Tam; † P = 0.019 for shCon / E2; P = ns (no significance) for shMEL / E2; ‡ Based on P <0.001 (shCon / E2 + Tam shMEL / E2 + Tam) and P = 0.043 (shCon / E2 vs. shMEL / E2) - RM ANOVA;
Figure 4C is IHC (mean ± SEM of 3 mice) for ER-alpha and PR in xenografted tumors of the proposed mouse group. * P <0.05 compared to shCon (2-tailed Student t-test). Scale bar: 100 m;
Figure 4D is a tumor growth curve ( n = 8; mean ± SEM per group) for tamoxifen (5 mg / pellet) or placebo treated control or NOD / SCID mice transplanted with MEL-18-overexpressed MDA-MB- . P <0.001 (days), P = 0.026 (group x days) - Based on RM ANOVA. ** for P = 0.006 Con / Tam; † P = 0.026 for MEL-18 / placebo (post-hook LSD test);
FIG. 4E shows the results of analysis of OS and DFS according to MEL-18 expression in 103 tamoxifen-treated ER-α positive human breast tumors using the Kaplan-Meier method.
Figure 5 is a series of data showing that MEL-18 modulates ESR1 transcription by inhibiting the SUMOylation of the ESR1 transcription factors p53 and SP1,
5A is a photograph showing immunoblotting of a cell lysate treated with 20 mM NEM. The amount of sumoylated protein was quantified by measuring the ratio of sumoylated protein / total protein;
Figure 5B is a Venn diagram showing the relationship between microarray results for MCF-7 cells expressing MEL-18 shRNA and results for MCF-7 cells treated with RITA (GSE13291, ref. 36);
Figure 5C shows that MCF-7 cells expressing MEL-18 siRNA (siMEL) were co-transfected with WT or SUMO-deficient mutant constructs of p53 or SP1 and ESR1 pro-luciferase and luciferase reporter assay Respectively. Data are presented as means ± SD ( n = 3). * And †, P <0.05 compared to siCon / Con and siMEL / Con, respectively (2-tailed Student t-test);
FIG. 5D shows the results of ChIP-qPCR analysis showing the amount of ESR1 transcription factor recruited into the ESR1 promoter in the proposed cells. Data are presented as means ± SD ( n = 3). * P <0.05 compared with shCon (2-tailed Student t-test);
Figure 5E is data showing the effect of gingic acid on the expression of ER-a in MEL-18-silenced cells. Cells were treated with 100 mM ginkholic acid for 24 h and immunoblotted. Concurrent samples tested on separate gels are presented. Data were quantified by measuring the immunoblot band density from three independent experiments (mean +/- SD). * P <0.05 compared with shCon; † P <0.05 compared to shMEL (2-tailed Student t-test). All data presented represent three independent experiments.
Figure 6 is a series of data showing that MEL-18 enhances desumoylation of ESR1 transcription factors by inhibiting the degradation of ubiquitin-proteasomes of SENP1,
Figure 6A is the result of analysis of SENP1 expression through immunoblotting and qRT-PCR;
Figures 6B and C show immunoblotting of the cell lysates of control and MEL-18-silenced MCF-7 cells treated with (B) 100 μg / ml CHX or (C) for 2 h with DMSO or 10 μM MG132 Results. The quantification of SENP1 protein stability is shown in the graph. Data in A and B are presented as the mean ± SD of three duplicate measurements. * P <0.05 compared with shCon (2-tailed Student t-test);
Figure 6D is the result of in vivo SENP1 ubiquitination assay in 293T cells;
Figure 6E is the result of endogenous SENP1 protein ubiquitination levels in control and MEL-18-silenced MCF-7 cells treated or untreated with 40 [mu] M MG132 for 6 h;
6F-H are the results of immunoblotting of the proposed cell lines. Cells that stably express WT RING1B or a catalytically inactive RING1B mutant (Mut) (F) or SENP1 (H) were generated from MEL-18-silenced MCF-7 cells. For BMI-1 knockdown, non-targeted or BMI-1 siRNA was transfected into MEL-18-silenced MCF-7 cells for 48 h. A known RING1B E3 ligase substrate, a geminin protein, was used as a positive control for the measurement of RING1B activity. All data represent three independent experiments.
Figure 7 is a schematic illustration of a proposed model for the modulation of hormone-dependent breast cancer by MEL-18,
Figure 7A shows a schematic model for modulation of SUMO-dependent ESR1 transcription by MEL-18. The loss of MEL-18 promotes SUMO activation through a direct bond between the SUMO E2 enzyme Ubc9 and its substrate. Moreover, MEL-18 depletion inhibits the desumoylation activity of SENP1 by enhancing the BMI-1-1 / RING1B E3 ubiquitin ligase complex-mediated ubiquitin (Ub) -protease cleavage of SENP1. Through these two pathways, MEL-18 inhibits sumoylation of p53. Alternatively, MEL-18 mediates SP1 sumoylation via the SENP1-mediated desamolization pathway. Increasing p53 and SP1 sumoylation through MEL-18 silencing inhibits their recruitment to the ESR1 promoter and downregulates ER-a expression;
Figure 7B is a proposed model for balancing hormone dependence and independence by the polycomb protein MEL-18 in human breast cancer. In Luminal breast cancer, MEL-18 contributes to the maintenance of the expression of the hormone receptors ER-α and PR by inhibiting SUMOylation of ESR1 transcription factors and promoting ER-α-dependent transcriptional activity, respectively, but not HER2 . However, when the expression of MEL-18 is lost during breast cancer progression, the tumor develops resistance to hormone-dependent anti-hormone therapy, and the phenotype of hormone receptor-negative breast cancer including TNBC causes loss of ESR1 and PR expression and HER2 amplification . &Lt; / RTI &gt; Thus, MEL-18 acts as a regulator of hormone receptor expression and is an important determinant of hormone dependence and independence in human breast cancer.
8 is a graph showing the clinical validity results of MEL- 18 expression in the human breast cancer cohort, wherein FIG. 8A-C shows OS and DFS in Kaplan-Meir plotter in the subtype of breast cancer patients according to MEL- 18 mRNA expression level ( Http://kmplot.com/analysis ). FIG.
Figure 9 is a series of data showing the effect of MEL-18 on hormone receptor transcription and activity,
Figure 9A is the result of immunoblotting of breast cancer cell line cell lysate to determine the expression of the proposed protein. beta -actin was used as a loading control;
Figure 9B shows the results of qRT-PCR verifying mRNA levels of PR ( PGR ) in MCF-7 cells expressing control (shCon) or MEL-18 shRNA (shMEL);
FIG. 9C is a diagrammatic representation of the promoter region of the human ESR1 gene and the promoter fragment of ESR1 cloned into the luciferase reporter vector described in the prior art. The blue and red lines represent the binding regions previously described in the transcription factor and the exogenous regulator of ESR1 transcription (above). In the proximal promoter of ESR1 the binding region of p53 and SP1 is presented (below);
Figure 9D is a graph showing the effect of MDA-MB-468 cells transiently transfected with control (siCon) or MEL-18 siRNA (siMEL) or transiently transfected with empty vector (Con) or MEL-18 cDNA Lt ; RTI ID = 0.0 &gt; ESR1 < / RTI &gt; promoter activity;
Figure 9E illustrates the effect of MEL-18 on PR transcription. Luciferase reporter assays were used to measure PR promoter activity in MEL-18-silenced MCF-7 cells;
Figure 9F shows the results of PRE luciferase assay of control and MEL-18-silenced MCF-7 cells in the presence or absence of synthetic progestin (Pg) 10 nM R5020 for 24 h. The error bars in B and DF represent the mean ± SD of three duplicate experiments. * P <0.05 - compared to control (shCon, siCon, or Con) based on 2-tailed Student t-test.
Figure 10 is a series of data showing the effect of MEL-18 on hormone receptor activity,
Fig. 10A shows the results of measurement of ERE luciferase activity in cell lines presented in the presence and absence of 10 nM E2 for 24 h. The error bars represent the mean ± SD of three duplicate experiments. * P < 0.05 - comparison with control (shCon or Con) based on 2-tailed Student t-test;
Figure 10B is a graph showing the effect of MEL-18-silenced (left), or MEL-18-overexpressing (right) cells in the presence or absence of 10 nM E2 (10 nM in MCF-7 cells or 20 nM in MDA- ) Cells with TFF1 (also referred to as pS2) and PR expression. Concurrent samples tested on separate gels are presented. The data presented represent three independent experiments.
Figure 11 is a series of data showing the effect of hormone activity on MEL-18 expression,
Figures 11A-D show that cells were treated with 10 nM E2 (A and C) or 10 nM synthetic progestin (Pg) R5020 (B and D) for the indicated period and immunoblotting (A and B, above), qRT-PCR And B, below) or MEL- 18 promoter activity assays (C and D). The TFF1 and ERE-luc or HG- EGF and PRE-luc was used as a positive control for each E2- and R5020- inducing activity. The error bars represent the mean ± SD of three duplicate samples. * P <0.05 - compared to control (0 h) based on 2-tailed Student t-test.
12 is a series of data showing the effect of MEL-18 on estrogen response of breast cancer cells,
Figure 12A shows the results of cells treated with 10 nM E2 or ethanol (vehicle) and analyzed for cell growth by MTT assay. Results are presented as means ± SD of three duplicate experiments. * And †, P < 0.05 - compared to the control (shCon or Con) and excipient (E2-), respectively (2-tailed Student t-test);
Figure 12B shows the results of AKT activity measured by immunoblotting with anti-phospho-AKT antibody in the indicated cell line treated with E2 or E2 for 48h.
Figure 13 is a set of data showing the effect of MEL-18 depletion on estrogen-independent T-470 breast tumor growth in vivo, in which T47D cells expressing control (shCon) or MEL-18 shRNA (shMEL) Were transplanted into the breast fat layer of NOD / SCID mice ( n = 8) without injection. Tumor growth was monitored in xenografted mice by monitoring tumor size for 8 weeks. Data are presented as means ± SEM. ** P <0.01 (group x days) - Based on RM ANOVA.
14 is a series of data showing the effect of MEL-18 on the response of breast cancer cells to tamoxifen,
Figure 14A shows the results of cell growth assayed by MTT assay in which cells were treated with tamoxifen (Tam) or ethanol (vehicle) at the indicated volume (μM) for 5 days. Data are presented as the mean ± SD of three duplicate experiments. P <0.05 - compared to shCon or Con (2-tailed Student t-test);
FIG. 14B shows the results of MTT analysis of the growth of these cells treated with 1 μM tamoxifen for 5 days after the generation of MEL-18-silenced MCF-7 cells stably expressing ER-α (left) . MEL-18-silenced MCF-7 cells transfected with control or control (siCon) or ER-alpha siRNA (siER) were treated with 10 [mu] M tamoxifen for 3 days (right) and MTT assay was performed. The error bars represent the mean ± SD ( n = 3);
Figure 14C shows the effect of tamoxifen (Tam) or placebo in a xenografted mouse with a control (Con) or MEL-18-overexpressing MDA-MB-231 cell-based tumor for the response of TNBC cells to tamoxifen in vivo The effect of MEL-18 was analyzed ( n = 8 per group). Tumor size was monitored for 42 days. Data are presented as means ± SEM. P <0.001 (days), P <0.001 (group x days) - Based on RM ANOVA. ** P = 0.003, Con / Tam vs. MEL-18 / Tam (post-hook LSD test).
Figure 15 is a series of data showing the effect of AKT activity on MEL-18-mediated regulation of tamoxifen responses,
FIG. 15A shows the results of IHC analysis of phosphorylated AKT (above) for analyzing the effect of MEL-18 on AKT activity in vivo, and Ki-67 and TUNEL for in vivo analysis of cell proliferation and apoptosis, respectively The analysis results (below);
Figure 15B shows the results of MTT analysis of cells treated with 10 [mu] M tamoxifen, 1 [mu] M BKM120 (BKM), or both for 48 h. The error bars represent the mean ± SD of three duplicate measurements. * P <0.05 compared with shCon; † P <0.05 compared with Tam (2-tailed Student t-test);
FIG. 15C shows the results of administration of tamoxifen, BKM, or both to control mice injected with E2 pellets or xenografted mice bearing MEL-18-silenced MCF-7 cell-based tumors ( n = 5 E2 and E2 + For a full group, for n = 8 E2 + BKM group; for n = 7 E2 + Tam + BKM group). Data are presented as means ± SEM. P <0.001 (days), P <0.001 (group x days) - Based on RM ANOVA. P = ns (no significance), shCon / E2 + Tam vs shCon / E2 + BKM; † P = 0.019, shCon / E2 + Full shCon / E2 + Tam + BKM; ** P = 0.009, shMEL / E2 + Full versus shMEL / E2 + BKM; *** P <0.001, shMEL / E2 + Full shMEL / E2 + Tam + BKM (Post Hook LSD Test).
Figure 16 is a series of data showing that the overall expression of ESR1, the exogenous state of ESR1 , and the ESR1 transcription factor is not affected by MEL-18 expression,
Figure 16A shows the results of immunoblotting (left) and RT-PCR (right) used to measure the expression of an exogenous modifier involved in ESR1 gene regulation in MEL-18-silenced MCF-7 cells;
Figure 16B shows the results of ChIP analysis showing the levels of HDAC1 and DNMT family protein recruitment in the histone deformation state and the proximal promoter region of ESR1 in MEL-18-silenced MCF-7 cells. A vertical white line in the gel image indicates that the lanes were developed on the same gel, which was not continuous;
FIG. 16C shows immunoblotting (left) and RT-PCR (right) results of measuring the expression of PcG protein in MEL-18-silenced MCF-7 cells and MEL-18-overexpressing MDA-MB-468 cells. Concurrent samples tested on separate gels are presented. * Loading control of GAPDH , RT-PCR;
Figure 16D is the result of the expression of ESR1 transcription factor in the presented cell line by immunoblotting. Concurrent samples tested on separate gels are presented. Relative immunoblot and RT-PCR band densities are presented below each band.
Figure 17 is a series of data showing that MEL-18 is a negative SUMO E3 ligase in p53 but not SP1,
FIGS. 17A and B show the effect of 293T cells transfected with pCI-neo (Con) or pCI-neo-MEL-18-FLAG (MEL-18-FLAG) to measure the interaction between MEL-18 and ESR1 transcription factors Lt; / RTI &gt; IB, immunoblot;
Figures 17C and D are the in vitro SUMO analysis results of p53 (C) and SP1 (D) in the presence or absence of MEL-18;
Figure 17E is the in vitro SUMO analysis of p53 and SP1 in 293T cells co-transfected with the indicated plasmid vectors. Data represent three independent experiments.
18 is a series of data showing the effect of MEL-18 on the SUMOylation of transcription factors and the modulation of their target genes,
Figure 18A is a GO analysis of our common target genes for MEL-18 and p53 / SP1 based on a comparison of two microarray results (our data versus GSE13291 data);
Figure 18B shows the results of luciferase reporter assays on MCF-7 cells co-transfected with WT or SUMO-deficient mutant constructs of p53 or SP1 and ER pro-luciferase. * P <0.05 compared with Con; † P <0.05 compared to WT protein (2-tailed Student t-test);
Figure 18C shows the binding of WT p53 and SUMO-deficient p53 K386R mutants to the ESR1 promoter region. 293T cells were transfected with the proposed cDNA for 48h and ChIP analysis was performed. * P <0.05 compared to p53 WT (2-tailed Student t-test). Lack of SUMOylation in the P53 K386R mutant was confirmed by immunoblotting.
18D is a graph showing the inhibitory effect of SUMO formation on ESR1 transcriptional activity in TNBC cells. Cells co-transfected with the ESR1 promoter construct and MEL-18 cDNA or empty vector were treated with 10 [mu] M ginkcolic acid (gink) for 24 h and luciferase reporter assays were performed;
Figure 18E shows the results of luciferase reporter assays with transfected siRNA, cDNA and ESRl promoter constructs for 48 h to analyze the effect of p53 and SP1 on MEL-18-induced ESR1 transcription. * And †, P <0.05 - compared with Con and siCon respectively (2-tailed Student t-test). Data from BE are presented as mean ± SD of three duplicate measurements.
Figure 19 is a series of data showing the effect of MEL-18 on the binding of transcription factors in a target promoter,
Figures 19A and B are the results of ChIP analysis showing the incubation of proteins presented in the ESR1 (A) or CDKN1A (B) region. Data are presented as means ± SD ( n = 3). * P <0.05 compared to control (Con or shCon) based on 2-tailed Student t-test.
Figure 20 is a series of data showing the effect of MEL-18 on the expression and activity of SUMOylation / desamolization-regulatory factors,
Figure 20A shows the results of immunoblotting of SUMO-related factor expression in MEL-18-silenced (left) and MEL-18-overexpressing (right) cell lines. A concurrent sample tested on a separate gel is presented;
Figure 20B shows the effect of MEL-18 expression on the de-sumoylation activity of SENP1. For in vitro desaltingo assay, cell lysates from control and MEL-18-silenced MCF-7 cells were incubated with HA-SUMO-1-VS as described in the Methods section and incubated with SENP1 antibody Immunoblotting was performed on the sample. Data represent three independent experiments.
Figure 21 is a series of data showing that expression of SENP1 and enzyme activity are important for the regulation of ESR1 and PR transcription,
Figures 21A-C show the results of immunoblotting (A), qRT-PCR (Fig. 21B) to determine ER-alpha expression levels in MCF-7 cells transfected with siCon- B) and luciferase reporter assay (C). For immunoblotting against SUMOylated p53 and SP1, cell lysates were prepared after treatment with 20 mM NEM. A parallel sample tested on a separate gel is shown in (A). Data are presented as means ± SD ( n = 3). * P <0.05 - compared with siCon (2-tailed Student t-test);
21D shows the results of in vivo SUMO analysis of p53 and SP1 in 293T cells transfected with FLAG-SENP1 WT (SENP1 WT) or the catalytic inactivation mutant SENP1 (SENP1 Mut) vector. The black split line in the blot indicates that the lanes were derived from the same gel that was not continuous;
21E and F are the results of analysis of ESR1 and PR promoter activity in MCF-7 cells transiently transfected with WT or mutant SENP1 plasmid (right). Data are presented as means ± SD ( n = 3). * And †, P <0.05 - compared to control and WT SENP1, respectively (2-tailed Student t-test).
Figure 22 is a series of data showing the effect of MEL-18 on SENP1 expression in clinical specimens and xenografts in vivo,
22A is a bar graph (right) showing the correlation between representative IHC images of SENP1 staining (left) and MEL18 and SENP1 expression in 223 human breast tumors. Scale bar: 100μm. * P &lt; 0.05 (Fisher project test);
Figure 22B shows the expression status of SENP1 in NOD / SCID mice transplanted with control (shCon) or MEL-18-silenced (shMEL) MCF-7 cells in the presence or absence of E2 administration, as determined by IHC;
Figure 22C shows the results of IHC analysis of SENP1 in the presented samples of NOD / SCID mice administered with tamoxifen for 4 weeks. In B and C the data is presented as means ± SD ( n = 3). Scale bar: 100μm.

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are intended to assist the understanding of the present invention and should not be construed as limiting the scope of the present invention.

Cell culture and drug treatment - All cell lines were purchased from the American Type Culture Collection (ATCC). Human breast cancer cell lines were cultured in DMEM-free phenol red (Welgene) containing 10% FBS. The 293T cell line was cultured according to the previously reported procedure (Park JH, Lee JY, Shin DH, Jang KS, Kim HJ, and Kong G. Loss of Mel-18 inducing tumor angiogenesis through enhancing the activity and expression of HIF-1alpha mediated by PTEN / PI3K / Akt pathway. Oncogene. 2011; 30 (45): 4578-89). CHX and MG132 were obtained from Calbiochem, and digoxanthic acid, E2, 4-hydroxy tamoxifen, R5020, and LY294002 were obtained from Sigma-Aldrich. For E2 and 4-hydroxy tamoxifen treatment, cells were cultured in phenol-red-free DMEM supplemented with 10% charcoal / dextran-treated FBS. The pan-PI3K inhibitor BKM120 (A-1108) was purchased from Active Biochemicals.

Gene Expression Microarray Analysis - Total RNA was isolated from MCF-7 cells expressing the control or MEL-18 shRNA, and a large number of cDNA and biotinylated cRNA were isolated using the Illumina TotalPrep ™ RNA Amplification Kit (Ambion, Inc.) I created a copy. After purification, cRNA was hybridized with Human HT-12 v4 Expression BeadChip (Illumina) at 58 ° C for 16 h through a multi-step procedure according to the manufacturer's instructions. Next, the chips were cleaned and dried, scanned from Bead Array Reader (Illumina), and raw data was extracted using GenomeStudio version 2011.1 software (Illumina). The presence / absence title was based on the classification method based on the detected P value calculated by GenomeStudio.

A gene with a detected P value of < 0.05 was classified as present, and all other genes were classified as members. Selected gene signal values were logarithmically transformed and normalized using the miniscule method. All of the genes showing an absolute magnitude change of at least 1.5 between the comparison groups were considered to be differentially expressed. These data were deposited with the Gene Expression Omnibus (GEO) and received accession number GSE64716. Additional analyzes were performed using the Database for Annotation, Visualization, and Integrated Discovery (DAVID) to functionally classify genes involved in different biological processes. Gene expression microarray profiles (36) of MCF-7 cells treated with the PAM305 gene list (46) for the classification of breast cancer cell lines as luminal and basal subtype and the p53 reactivation factor RITA (GSE13297) from GEO Was used for comparison with the identified MEL-18 target gene based on microarray data.

Data collection and analysis of microarray data sets from breast cancer patient populations - Seven publicly available data sets of human breast cancer gene expression microarrays are available at http://www.ncbi.nlm.nih.gov/geo (Richardson et al ., GSE7904 (21); Li et al, GSE19615 (22); MAQC-II project, GSE20194 (23); Hatzis et al, GSE25066 (24); Bos et al, GSE12276 (27)), http...: //www.ebi.ac.uk/arrayexpress (Chin et al., E -TABM-158 (25)), and http://bioinformatics.mdanderson.org/pubdata.html (Gibson et al., MDA133 (26 )) And analyzed again. Expression profiles of MEL- 18 , ESR1 , PGR , FOXA1 , and GATA3 were extracted from this independent data set and the expression of MEL-18 and the relationship of each of these genes was determined by calculating the correlation coefficient (r value). (Luminal, ER + / HER2-; HER2, ER + / HER2 + or ER- / HER2 +; and TNBC, ER- / PR- / HER2-) based on ER, PR, And the IHC results for that were available for all three markers, allowing comparison of the MEL-18 expression pattern in different breast cancer subtypes. Kaplan-Meier Plotter ( http://kmplot.com/analysis ) was used as previously reported for meta-analysis of the relationship between MEL-18 mRNA expression and OS and DFS of breast cancer patients (Gyorffy B, Lanczky A, The results of this study are as follows: (1) the number of patients with breast cancer, (2) the number of patients with breast cancer, (3) the number of patients with breast cancer, (4) 3): 725-31).

Chromatin Immunoprecipitation ( ChIP ) Assay - ChIP analysis was performed according to the manufacturer's instructions provided in the ChIP Assay Kit (Upstate Biotechnology). The binding of the transcription factor and the target promoter was confirmed by the proximal promoters (5'-CGCTCCAAATCGAGTTGTGCCT-3 'and 5'-CCGGGCCTCCAACTTTAAGTACTGG-3' and CDKN1A ( p21 ) promoters (5'- GCTGTGGCTCTGATTGGCTTT- 3 'and 5'- ACAGGCAGCCCAAGGACAAA- (Macaluso M, Montanari M, Noto PB, Gregorio V, Bronner C, and Giordano A. Epigenetic modulation of estrogen in vitro). The primers targeting the extracorporeal strain region of the ESR1 promoter were as previously reported Receptor-alpha by pRb family proteins: a novel mechanism of breast cancer Cancer Res 2007; 67 (16): 7731-7). The incubation of ChIP signals is performed quantitatively in real time (qRT) -PCR Verified.

SUMO Degradation / De-SUMO Analysis - In- vitro SUMO reformation was evaluated according to the manufacturer's instructions for the SUMOlink SUMO-1 kit (40120, Active Motif). Recombinant GST-MEL-18 protein was obtained from Novus Biologicals. Recombinant p53 and SP1 protein (PR-733) were obtained from Active Motif and Jena Biosciences, respectively. For in vivo SUMO analysis, 293T cells were transfected for 36 h. Cell extracts were immunoprecipitated using anti-SUMO-1 antibody and analyzed by immunoblotting using anti-p53 or anti-SP1 antibodies. The deSumoylation assay was analyzed using HA-SUMO-l-vinyl-sulfone (Boston Biochem) as previously reported (Kolli N, Mikolajczyk J, Drag M, Mukhopadhyay D, Moffatt N, Dasso M, Salvesen G , and Wilkinson KD. Distribution and paralogue specificity of mammalian deSumoylating enzymes. Biochem J. 2010; 430 (2): 335-44).

In vivo Ubiquitination assay - In vivo ubiquitination assay to detect SENP1 protein ubiquitination was performed as previously reported (Qian T, Lee JY, Park JH, Kim HJ, and Kong G. Id1 enhances RING1b E3 ubiquitin ligase activity through the Mel-18 / Bmi-1 polycomb group complex. Oncogene. 2010; 29 (43): 5818-27). Briefly, 293T cells were co-transfected with HA-ubiquitin and FLAG-SENP1 plasmids with empty or MEL-18-expression vectors for 48 h. Cell lysates were immunoprecipitated using anti-FLAG antibodies and analyzed by immunoblotting using anti-HA or anti-FLAG antibodies. To detect endogenous SENP1 protein ubiquitination, MCF-7 cells expressing MEL-18 or control shRNA were treated with 40 [mu] M MG132 for 6 h. Next, the sample was immunoprecipitated using an anti-SNP1 antibody and immunoblotted using anti-ubiquitin antibody.

Orthotopic xenografts and histopathological analysis of 5-week-old female non-obese diabetic / severe combined immunodeficient (NOD / SCID) mice were purchased from Korea Research Institute of Bioscience and Biotechnology (Republic of Korea War). To investigate the effect of MEL-18 on estrogen-independent tumor growth, 4 x 106 MCF-7 or T47D luminal cells expressing lentiviral MEL-18 or control shRNA were cultured in the left (control) and right (MEL-18 shRNA) injected into the breast fat layer of female NOD / SCID mice and monitored for tumor formation. To test the effect of MEL-18 on anti-estrogen therapy, mice were transplanted with E2 pellet (0.72 mg / pellet; 60-d release) subcutaneously one week prior to cancer cell transplantation. Approximately 4 x 10 ⁶ control or MEL-18-silenced MCF-7 cells were then injected into the fat layer of the mice as described above. After 1 week, the experimental animals were not subcutaneously injected with tamoxifen pellets (5 mg / pellet; 60-d release). In order to treat xenotransplanted mice with PI3K inhibitors and tamoxifen, Tamoxifen was administered to NOD / SCID mice with E2 pellet-implanted control or MEL-18-silenced MCF-7 cell- BKM120 (30 mg / kg, 10% NMP and 90% PEG300) was administered via oral gavage twice a week for one additional day and two weeks (6 days on / 1 day off, 6 IW) Dissolved in freshly prepared solution). To evaluate the effect of MEL-18 overexpression on the response of TNBC to tamoxifen in vivo, 1 x 10 ⁶ MDA-MB-231 cells expressing empty vector or lentiviral MEL-18 cDNA in NOD / SCID mice or 4 x 10 ⁶ MDA-MB-468 cells were xenotransplanted and one week after cell transplantation, tamoxifen (5 mg) or placebo pellets were subcutaneously injected. Tumor growth was measured twice weekly for 4-7 weeks. The tumor volume was calculated as 1/2 x long diameter x short diameter ² . Following tumor resection, IHC assays were performed as previously reported using serial sections of tumors from three independent xenografted mice (Park JH, Lee JY, Shin DH, Jang KS, Kim HJ, and Kong G. Loss of Mel-18 inducing tumor angiogenesis through enhancing the activity and expression of HIF-1alpha mediated by the PTEN / PI3K / Akt pathway. Oncogene. 2011; 30 (45): 4578-89). The results are scored by multiplying the percentage of benign cells by the intensity of the staining intensity as described in the IHC staining section. Total score 4 was chosen as the threshold. Percent of benign cells were measured to quantify the results of Ki-67 proliferation index and cell suicide index based on TUNEL staining (Millipore).

Statistical significance was determined using the 2-tailed Student t-test to determine the difference between the control and experimental groups. For multiple group comparisons and repeated measurements of in vivo data, Dunnett T3 test was performed after Welch ANOVA for the unequal variance, or post-hook LSD test after repeat-measurement ANOV (RMANOVA) for the univariate. Fisher's Eject test was used to examine the correlation of MEL-18 expression with expression of hormone receptors and SENP1 and clinicopathological variability in human samples. The Kaplan-Meier curve of the OS and DFS analysis was evaluated using a log-rank test. Univariate and multivariate survival analyzes were performed using the Cox proportional hazards regression model to evaluate independent prognostic factors. These analyzes were performed using SPSS software (Ver. 12.0, SPSS). Differences in MEL-18 expression levels between breast cancer subtypes were analyzed by ANOVA in a fair-wise comparison. Spearman rank correlation coefficients were used for correlation analysis between two genes. Both analyzes were performed using the R statistical package. SAS software was used to calculate the Poisson distribution and evaluate the significance of tumor incidence. In all cases a P value of <0.05 was considered significant.

On the other hand, in the present invention, all animal tests were conducted in accordance with the procedures approved by the Hanyang University Animal Care and Use Committee (Seoul, Korea).

Patients and Surgical Samples - For survival analysis, we enrolled 223 breast cancer patients who underwent surgery successfully from January 2000 to December 2005 at Hanyang University Hospital (Seoul, Korea). An organization that includes information about the patient's age, histological type, tumor grade, tumor size, lymph node status, AJCC stage, ER-α and PR status, HER2 status, adjuvant chemotherapy, radiotherapy, Pathology and clinical data were obtained from pathology reports and medical records. All cases were primary and sporadic and there was no preoperative treatment. Patient samples were evenly related to the surgical procedure, postoperative therapy and follow-up schedule. Most patients underwent modified radiosurgery or conservative breast surgery without resection of the axillary lymph nodes, followed by adjuvant chemotherapy and / or hormone therapy. A group of low-risk patients with stage I cancer who were positive for hormone receptors received only tamoxifen treatment after surgery. I (high-risk group) or stage II patients received chemotherapy with adriamycin and cyclophosphamide (AC) or cyclophosphamide, methotrexate and 5-fluorouracil (CMF). Patients with stage III cancer received chemotherapy with AC and paclitaxel. As adjuvant hormone therapy, tamoxifen was administered to patients who showed positive ER-α status after chemotherapy. Patients with stage III or stage II tumors greater than 5 cm in diameter underwent radiation therapy. The mean follow-up period was 75.7 months, during which 32 (14.3%) patients died and 191 (85.7%) patients survived.

Using hematoxylin and eosin-stained slides of tissue microarrays and IHC stained -formalin-fixed, paraffin-embedded tissue blocks, morphologically the most representative and non-necrotic areas were defined. Single-tissue cores (2 mm in diameter) were sampled from each paraffin block and assembled into a recipe paraffin block using a tissue microarray (TMA) instrument (AccuMax array, ISU ABXIS). The tissue fragments were cut into 4 mu m thick slices and paraffin was removed. Immunoblotting was performed using a Bond Max automated immunostaining system (Vision BioSystems). Heat-induced epitope recovery was performed using Bond Epitope Retrieval solution. Endogenous peroxidase activity was blocked with 0.3% hydrogen peroxide. This fragment was stained for 15 minutes at room temperature using a primary antibody against MEL-18 (1:50 dilution, sc-10744; Santa Cruz Biotechnology) and SENP1 (1: 200 dilution, AP1230; Abgent). Slides were incubated in post-first reagent for 15 minutes at room temperature. The reaction was developed using a BOND Polymer Refine Detection Reagent and colorimetrically developed using 3,3'-diaminobenzidine tetrahydrochloride (DAB; Sigma-Aldrich) as chromogen. Both pathologists evaluated the MEL-18 and SENP1 immunoreactivity in a blind fashion. The intensity and area of staining were quantified using a German semi-quantitative score recording system. The scores in each sample were assigned based on the percentage of positive stained cells, as follows: 0 unstained cells; 1 cell stained with 1 to 24%; 2 cells stained with 25-49%; 3 cells stained with 50-74% staining; And 4 to 75% to 100% stained cells. Other scores were assigned based on staining intensity and were as follows: negative staining 0 point; Weak dyeing 1 point; 2 intermediate dyes; And 3 points of strong dyeing. The final score was obtained by multiplying the two scores. If the final score was 4 or higher, the expression status was considered positive.

Plasmid and siRNAs - FLAG-tagged MEL-18 cDNA and approximately 1 kb MEL-18 promoter were generated by PCR and inserted into pCI-neo vector (Promega) and pGL3 luciferase reporter vector (Promega), respectively. ER-α cDNA and ERE luciferase constructs were provided by Shin In-cheol (Seoul, Korea, Hanyang University, ref. 5). The ESR1 promoter reporter constructs ER proAB, proC and prod in the pGL3-basic vector were provided by Hayashi Shinichi (Saitama Cancer Center, Saitama, Japan; ref. 1). ER proE and proF (ref. 1) were generated by PCR and cloned into pGL3 vector. PRE luciferase and pcDNA3-HA-SUMO-1 constructs were obtained from Addgene (Cambridge, Mass., USA) and were used in the presence of Donald McDonnell (Durham, North Carolina, Massachusetts, Boston, Harvard Medical School, ref. 7). FLAG-tagged UBC9 cDNA was provided by Kim, Chul-Keun (Hanyang University, Seoul, Korea). HA-tagged ubiquitin constructs were provided by Moselen (Israel, Rehoboth, Waysman Institute of Science; ref. 8). RING1B wild-type and C51W / C54S mutant constructs (provided by Kang Sungman, Korea, Seoul, Korea University, ref. 9) were inserted into the pCI-neo vector. The p53 wild-type and sumo-deficient K386R mutant constructs were generated by PCR and mutagenesis respectively and cloned into the pCI-neo vector. The SP1 wild-type and E18A mutant constructs were provided by Heng Jianjing (Tungan, Taiwan, National Chungkang University, ref. 10). The FLAG-tagged SENP1 wild-type or inactive mutant (R630L, K631M) construct was obtained from Addgene and deposited by Edward Yes (University of Texas Emdenderson Cancer Center, ref. 11, Houston, Texas, USA). For SENP1 stable expression, SENP1 wild-type cDNA was subcloned into pCI-neo vector. Non-targeted siRNA and siRNA targeting ER-alpha, BMI-1, p53, Sp1 and SENP1 were purchased from Bioneer Corporation for transient knockdown experiments. Control and SmartPool siRNA of MEL-18 were obtained from Dharmacon RNA Technologies. These siRNAs were transfected into cells with Lipofectamine 2000 (Invitrogen) for 48 h as described by the manufacturer.

The antibodies used for antibody- immunoblotting were: MEL-18 (sc-10744), ER-a (sc-543), PR (sc-539), HER2 BMI-1 (sc-10745), Geminin (sc-13015), RING1B (sc- (sc-8109), EED (sc-28701), YY1 (sc-7341), CBX2 (sc-19297), HA (sc-805), HDAC1 sc-20701), DNMT3a (sc-20703), and pRb2 / pl30 (sc-317) (Santa Cruz Biotechnology); HER2 (NCL-L-CB11) (Leica Biosystems); TFF1 12419, EZH2 3147, AKT 9272 and Ubiquitin 3936 (Cell Signaling Technology); H3Ac (06-599), H4Ac (06-866), H3K27me3 (07-449), p300 (05-257) and c-JUN (06-225) (Millipore); SUZ12 (ab12073), CBX7 (ab21873), H3K9me3 (ab8898) and p-AKT Ser473 (ab66138) (Abcam); SAE1 (AP1199), UBC9 (AP1064), SUMO2 / 3 (AP1224), PIAS1 (AB1243), PIAS2 (AP1246), PIAS4 (AP1249), CBX4 (AP2514), SENP2 (AP1232) and SENP3 (AP1234) (Abgent); beta-actin (Sigma-Aldrich).

Primer - a primer used for RT-PCR and qRT-PCR were as follows: MEL - 18 (PCGF2), 5'-GGCGGGATTTCTATGCAG-3 'and 5'-AATTCGATGGAGAGGCTGAC-3'; ESR1 , 5'-ACCATGACCCTCCACACCAAAGCATC-3 'and 5'-GTAGTTGTACACGGCGGGCTTGCTG-3'; TFF1 ( pS2 ) , 5'-GTACACGGAGGCCCAGACAGA-3 'and 5'-AGGGCGTGACACCAGGAAA-3'; PR , 5'-GGCCATACCTATCTCCCTGGA-3 'and 5'-CTCCACGTCCGACAGCGACT-3'; SENP1 , 5'-ACTGATAGTGAAGATGAATTTCCTGA-3 'and 5'-CATCCTGATTCCCATTACGAA-3'; GAPDH , 5'-CATGTTCCAATATGATTCCA-3 'and 5'-CCTGGAAGATGGTGATG-3'; HDAC1 , 5'-GGAAATCTATCGCCCTCACA-3 'and 5'-CTCGGACTTCTTTGCATGGT-3'; HDAC2 , 5'-GAGGTGGCTACACAATCCGT-3 'and 5'-TTCGACCTCCTTCTCCTTCA-3'; EP300 (p300) , 5'-AAACCCACCAGATGAGGAC-3 'and 5'-TATGCACTAGATGGCTCCGCAG-3'; DNMT1, 5'-ATGGCAGATGCCAACAGCCCC-3 'and 5'-CTCCTTCAGTTTCTGTTTGGGTG-3'; DNMT3A , 5'-GGGGACGTCCGCAGCGTCACAC-3 'and 5'-CAGGGTTGGACTCGAGAAATCGC-3'; SUV39H1 , 5'-GGAGAAAGATGGCGGAAA-3 'and 5'-GACAAGAAAGCTTGGCTAGT-3'; RBL2 ( pRB2 / p130) , 5'-GAGCTGTGCAGCCGCCTCAA-3 'and 5'-GGCTGTCGCCGCTGTTTCCT-3'.

Sean virus and stable transfection-MEL-18 For the stable overexpression or knockdown was established as lentivirus MEL-18 shRNA- infected cell lines with retroviruses that the MEL-18- overexpressing cell lines, each reported a conventional (Won HY , J J, Shin JH, Park JH, Nam JS, Kim HC, and Kong G. Loss of Mel-18 enhances breast cancer stem cell activity and tumorigenicity through activating Notch signaling mediated by the Wnt / TCF pathway. 26 (12): 5002-13; Park JH, Lee JY, Shin DH, Jang KS, Kim HJ and Kong G. Loss of Mel-18 induces tumor angiogenesis through enhancing the activity and expression of HIF-1alpha mediated by the PTEN / PI3K / Akt pathway. Oncogene. 2011; 30 (45): 4578-89). Cells were transfected with pCI-neo, pCI-neo-RNF2 C51W / C54S, or pCI-neo-SENP1 vectors to inhibit RING1B activity and restore SENP1 expression in MEL-18-silenced MCF-7 cells , 1 mg / ml G418 sulfate (Sigma-Aldrich).

Was dissolved in the cell radioactive immunoprecipitation analysis (RIPA) buffer immune blotting and immunoprecipitation. To detect SUMOylated proteins, cells were extracted from RIPA buffer containing 20 mM N-ethylmaleimide (NEM, Sigma-Aldrich) and sonicated. Immunoblotting was performed as previously reported (Won HY, Lee JY, Shin DH, Park JH, Nam JS, Kim HC, and Kong G. Loss of Mel-18 enhances breast cancer stem cell activity and tumorigenicity through activating Notch signaling mediated by the Wnt / TCF pathway. FASEB J. 2012; 26 (12): 5002-13). For co-immunoprecipitation, cell lysates of 293T cells transfected with pCI-neo or pCI-neo-MEL-18-FLAG vectors were immunoprecipitated using anti-p53 or anti-FLAG antibodies. The precipitate was analyzed by immunoblotting as described above. Immunoblot density was determined using AlphaEase FC software (AlphaInnotech) and normalized for the expression of protein beta-actin.

Reverse transcription (RT) -PCR and quantitative real-time ( qRT ) -PCR -total RNA isolation and RT-PCR were performed as previously reported (Won HY, Lee JY, Shin DH, Park JH, Nam JS, Kim HC , and Kong G. Loss of Mel-18 enhances breast cancer stem cell activity and tumorigenicity through activating Notch signaling mediated by the Wnt / TCF pathway. FASEB J. 2012; 26 (12): 5002-13). QRT-PCR was performed using a 7300 Real-Time PCR system and a SYBR Green Master Mix (Applied Biosystems) to quantitate RNA expression levels. These data were normalized for the expression of the housekeeping gene GAPDH.

Luciferase Reporter Assay - For luciferase reporter assays, cells were seeded in 12-well plates and transfected with reporter constructs and β-gal expression vectors for 24h or 48h. Next, the luciferase reporter assay was performed as previously reported (Lee JY, Jang KS, Shin DH, Oh MY, Kim HJ, Kim Y, Cancer Res. 2008; 68 (11): 4201-9).

Cell proliferation assay -The effect of MEL-18 on breast cancer cell growth upon treatment with tamoxifen was assessed as previously reported using 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide (MTT ) Were used to investigate breast cancer stem cell activity and tumorigenicity through activating Notch (Won HY, Lee JY, Shin DH, Park JH, Nam JS, Kim HC, and Kong G. Loss of Mel- signaling mediated by the Wnt / TCF pathway. FASEB J. 2012; 26 (12): 5002-13). Briefly, cells were seeded in 96-well plates and treated with either ethanol or tamoxifen. Five days after treatment, the cells were incubated in MTT dye solution at 37 ° C for 3 h and the reaction was terminated by addition of dissolution / stop solution. The absorbance at 570 nM was measured using a microplate reader.

result

The loss of MEL-18 represents poor prognosis and triple-negative of human breast cancer.

In order to confirm the novel tumor-suppressing function of MEL-18 in breast cancer, the present invention first examined the clinical validity of MEL-18 in 223 primary human breast cancers. Low MEL-18 expression correlated with higher tumor size (P = 0.001) and higher levels of the American Joint Committee on Cancer (AJCC) (P = 0.021) (see Table 1). Notably, MEL-18 expression was significantly associated with TNBC among the breast cancer subtypes (see Figure 1 and Table 1) (P = 0.003). In particular, MEL-18 expression was strongly correlated with ER-alpha and PR expression (P = 0.001 and 0.029, respectively) but not with HER2 overexpression (P = 0.164) (see Figure 1B and Table 1).

Clinical pathological features n Expression of MEL-18 P value
(Fisher project test) voice positivity AJCC step 0.021 Step I-II 164 91 (55.5%) 73 (44.5%) Step III-IV 59 43 (72.9%) 16 (27.1%) Tumor size 0.001 <5 cm 117 58 (49.6%) 59 (50.4%) > 5 cm 106 76 (71.7%) 30 (28.3%) Lymph node metastasis 0.497 voice 119 69 (58.0%) 50 (42.0%) positivity 104 65 (62.5%) 39 (37.5%) Histologic grade * 0.098 1-2 ratings 138 81 (58.7%) 57 (41.3%) 3 ranks 54 39 (72.2%) 15 (27.8%) ER-α status 0.001 voice 97 70 (72.2%) 27 (27.8%) positivity 126 64 (50.8%) 62 (49.2%) PR status 0.029 voice 103 70 (68.0%) 33 (32.0%) positivity 120 64 (53.3%) 56 (46.7%) HER2 status (IHC) 0.164 voice 181 113 (62.4%) 68 (37.6%) positivity 42 21 (50.0%) 21 (50.0%) Molecular Classification ** 0.003 Luminal 125 64 (51.2%) 61 (48.8%) HER2-positive 29 16 (55.2%) 13 (44.8%) triple 53 45 (84.9%) 8 (15.1%)

* Invasive ductal carcinoma only.

** Based on ER-α, PR and HER2 status.

To further validate these results in a wide range of clinical samples, the present invention analyzed several publicly available gene-expressing microarray data sets in breast cancer patients. Consistent with the clinical population results of the present invention, MEL-18 mRNA levels were significantly lower in the TNBC cases than in the LUMINAL and HER-2-positive cases in these independent data sets (see FIG. Furthermore, correlation analysis revealed that MEL-18 expression tended to be positively related to the expression of Luminal markers ESR1, PGR, GATA3 and FOXA1 (see Figures 1D and 2).

Data set
(Trustee no.) Ref. n Comparison with MELl-18 Expression
r value ( P value ) ESR1 PGR FOXA1 GATA3 Richardson et al., 2006 (GSE7904) 21 43 0.285
(0.025) 0.400
(0.001) 0.448
(<0.001) 0.459
(<0.001) Li et al., 2010
(GSE19615) 22 115 0.427
(<0.001) 0.465
(<0.001) 0.504
(<0.001) 0.505
(<0.001) MAQC-II, 2010
(GSE20194) 23 278 0.307
(<0.001) 0.182
(0.002) 0.313
(<0.001) 0.239
(<0.001) Hatzis et al., 2011
(GSE25066) 24 508 0.386
(<0.001) 0.252
(<0.001) 0.492
(<0.001) 0.434
(<0.001) Chin et al., 2006
(E-TABM-158) 25 100 0.385
(<0.001) 0.255
(0.005) 0.447
(<0.001) 0.425
(<0.001) Gibson et al., 2005
(MDA-133) 26 133 0.291
(<0.001) 0.155
(0.074) 0.399
(<0.001) 0.399
(<0.001) Bos et al., 2009
(GSE12276) 27 204 0.379
(<0.001) 0.363
(<0.001) 0.420
(<0.001) 0.446
(<0.001)

The mean expression of multiple probes for each gene on Affymetrix GeneChips was used to determine the correlation coefficient. The r values were calculated by Spearman rank correlation coefficient analysis. Score: +1 = perfect positive correlation; 0 = no correlation; And -1 = perfect inverse correlation. r > 0.3 and P < 0.05 showed a significant positive correlation.

By analyzing the association between MEL-18 expression and breast cancer survival using the Kaplan-Meir method, the log-rank test and the Cox regression model in turn, the loss of MEL-18 was associated with poorer overall survival (OS; P = 0.001 and 0.003 ) And disease-free survival (DFS; P = 0.011 and 0.003 respectively, FIGS. 1E and 2). In addition, multivariate survival analysis revealed that MEL-18 loss is an independent prognostic factor for poor OS (see Table 3).

Univariate Multivariate HR 95% CI P value HR 95% CI P value DFS step
(I or II vs. III or IV) 3.917 2.247-6.831 <0.001 3.104 1.308-7.366 0.01 Grade (1 or 2 vs. 3) 0.979 0.504-1.900 0.949 LN transition 2.33 1.307-4.152 0.004 1.063 0.440-2.565 0.893 ER-α (negative vs. positive) 0.566 0.324-0.989 0.046 0.692 0.390-1.228 0.208 PR (voice versus positive) 0.692 0.397-1.206 0.194 HER2 (negative vs positive) 0.951 0.462-1.957 0.891 MEL-18 (negative vs. positive) 0.349 0.174-0.698 0.003 0.524 0.253-1.084 0.082 OS step
(I or II vs. III or IV) 4.874 2.406-9.876 <0.001 5.316 1.608-17.570 0.06 Grade (1 or 2 vs. 3) 1.001 0.443-2.260 0.998 LN transition 2.386 1.150-4.949 0.019 0.651 0.191-2.223 0.493 ER-α (negative vs. positive) 0.509 0.251-1.031 0.061 PR (voice versus positive) 0.528 0.261-1.071 0.077 HER2 (negative vs positive) 0.821 0.316-2.133 0.686 MEL-18 (negative vs. positive) 0.165 0.050-0.543 0.003 0.226 0.068-0.755 0.016

* Cox regression risk model

HR = Hazard Ratio; CI = confidence interval

TNBC patients who exhibited MEL-18 expression also showed a trend of survival performance that was more favorable than patients who had MEL-18 negative (OS, P = 0.083; DFS, P = 0.178) Reference). Based on a meta-analysis-based Kaplan-Meier plotter with survival information for 4,142 breast cancer patients, the present invention also identified a significant association between lower MEL-18 mRNA levels and adverse survival, particularly in the luminal subtype (Figs. 8A and 8B). However, in the basal subtypes where MEL-18 loss may have already been present, no significant difference in survival was observed between groups expressing MEL-18 at high and low levels (FIG. 8C). Taken together, these data suggest that MEL-18 is used as a prognostic factor and a new marker for human breast cancer, and its loss is associated with hormone receptor-negative and triple-negative.

MEL-18 regulates hormone receptors.

The present invention also confirmed that MEL-18 is strongly expressed in hormone-receptor-positive cancer cell lines, but its expression is weak or absent in ER-a-negative and TNBC cell lines (Fig. 9A). Expression of other polycomb group (PcG) proteins, EZH2 and BMI-1, was not correlated with the hormone receptor status in these cell lines. In order to investigate the functional role of MEL-18 in hormone receptor-positive cells, gene-expressing microarrays were performed after MEL-18 knock down by shRNA translation into MCF-7 LUMINARY breast cancer cells. The depletion of MEL-18 compared to the control induced down-regulation of several luminal markers including ESR1 and PGR (1.6- and 1.9-fold reduction, respectively) and upregulation of various basal markers including CAV1, CAV2 and KRT17 (Fig. 2A). Moreover, the gene ontology (GO) analysis suggested that the MEL-18 target gene was significantly hatched in hormone-related physiological processes, including responses to hormone stimulation and mammary gland development (FIG. 2B). Because ER-alpha and PR are the most prevalent factors involved in hormone regulation in breast cancer, we further tested the effect of MEL-18 on these hormone receptors. Consistent with the results of the gene expression arrays, reduced protein and mRNA levels of ER-α and PR were observed after MEL-18 knockdown in both HER2-unmiluminated LUMINAL breast cancer cell lines MCF-7 and T47D (FIGS. 2C and D, 9B). Moreover, MEL-18 overexpression induced both ESR1 and PR expression in MDA-MB-231 and MDA-MB-468 TNBC cells (Fig. 2E and Fig. 9B). In particular, in TNBC cells, ER-alpha protein levels were slightly restored by overexpression of MEL-18 (FIG. 2C). The effect on HER2 expression was not observed in MEL-18-silenced luminal cells or MEL-18-overexpressing TNBC cells. Based on the luciferase reporter assay using the previously characterized ESR1 promoter, it was further confirmed that MEL-18 modulates the activity of the proximal ESR1 promoter named ESR1proAB (FIGS. 9C and 9D). MEL-18 knockdown also reduced PR promoter activity (Figure 9E). Taken together, these data indicate that MEL-18 transcriptionally regulates the expression of hormone receptors in both LUMINARY breast cancer and TNBC cells.

Loss of MEL- 18 confers resistance to estrogen independence and anti-hormone therapy .

In addition, the present invention investigated whether the regulation of ER-alpha expression by MEL-18 affects ER-alpha-dependent transcriptional activity. The MEL-18 knockdown disappeared the expression of 17? -Estradiol (E2) -induced estrogen-responsive element (ERE) luciferase activity and ER-alpha target genes TFF1 and PGR in a Luminal breast cancer cell line containing MCF-7 . In addition, MEL-18-overexpression restored E2-mediated ERE activity and target gene expression in TNBC cell lines (Figures 3A-3C and Figures 10A and 10B). In addition, reduced PR expression due to MEL-18 knockdown affected PRE luciferase activity (Fig. 9F). These data indicated that MEL-18 induces hormone receptor activation by modulating their expression. Furthermore, we examined the potential feedback mechanism for MEL-18 expression and hormone activity. However, MEL-18 expression did not change in response to estrogen or progesterone treatment (Figures 11A-11D). Next, we examined whether the loss of ER-alpha expression and activity due to MEL-18 knockdown in hormone receptor-positive cancer cells results in progression from the estrogen-dependent phenotype to the estrogen-independent phenotype. MEL-18 loss in MCF-7 and T47D cells increased cell growth independent of E2 treatment (Figure 12A). Conversely, the growth retardation caused by MEL-18 overexpression was mitigated by E2 treatment in MDA-MB-468 and MDA-MB-231 cells, indicating recovery of E2 signaling in TNBC cells due to overexpression of MEL-18 do. In addition, we have confirmed that MEL-18 negatively regulates AKT phosphorylation levels in these cells irrespective of E2 status, consistent with previous literature that MEL-18 inhibits AKT-dependent breast cancer cell growth (Lee JY , 2008; 68 (11): 679-7. [CrossRef], [PubMed], [Web of Science ®] 4201-9). In addition, we confirmed the effect of MEL-18 on estrogen-independent breast tumor growth in vivo. Notably, increased tumor formation was observed in the absence of E2 treatment in mouse xenografts of MEL-18 knockdown MCF-7 and T47D cells compared to control xenografts when measured by tumor incidence and growth rate (See FIG. 3D, Table 4, FIG. 13, and Table 5). Furthermore, IHC analysis demonstrated that tumors formed in control mice in the absence of E2 treatment showed low expression of MEL-18, ER-alpha and PR and that MEL-18 depletion further downregulated ER-alpha ).

group Tumor development (≥ 30 mm ³ , n = 8) Day 7 Day 13 Day 21 Day 28 Day 32 shCon 0/8 (0%) 0/8 (0%) 1/8 (12.5%) 6/8 (75%) 8/8 (100%) shMEL 1/8 (12.5%) 4/8 (50%) 5/8 (62.5%) 7/8 (87.5%) 8/8 (100%) P value <0.0001

Tumor incidence in NOD / SCID mice injected with MCF-7 expressing control (shCon) or MEL-18 shRNA (shMEL) in the absence of E2 injection. The significance of the tumor incidence difference was determined through the Poisson distribution analysis.

group Tumor development (n = 8) Day 7 Day 15 Day 22 Day 29 Day 36 Day 43 Day 52 shCon 0/8 (0%) 0/8 (0%) 0/8 (0%) 1/8 (12.5%) 2/8 (25%) 2/8 (25%) 2/8 (25%) shMEL 0/8 (0%) 1/8 (12.5%) 2/8 (25%) 6/8 (75%) 7/8 (87.5%) 7/8 (87.5%) 7/8 (87.5%) P value <0.0001

The incidence of tumors in NOD / SCID mice injected with T47D cells expressing control (shCon) or MEL-18 shRNA (shMEL) in the absence of E2 injection. The significance of the tumor incidence difference was determined through the Poisson distribution analysis.

Since ER-alpha loss is a major cause of anti-hormone therapy resistance, the present invention investigated the effect of MEL-18 on tamoxifen treatment in breast cancer cells. MEL-18 knockdown imparted tamoxifen resistance to LUMINARY breast cancer cells, and it is noteworthy that overexpression of MEL-18 restored the sensitivity of TNBC cells to tamoxifen (FIGS. 4A and 14A). This effect was mediated by ER- [alpha], because the recovery of ER-alpha expression eliminated tamoxifen resistance in MEL-18-silenced MCF-7 cells (Figure 14B). Moreover, the effect of transient ER-α knock down by siRNA in control MCF-7 cells was similar to that of MEL-18 knockdown. In agreement with these in vitro results, tamoxifen treatment inhibited anti-proliferative and anti-cellular suicide in mouse xenografts of MEL-18-silenced MCF-7 cells as determined by growth curve analysis and Ki-67 and TUNEL staining (Fig. 4B and Fig. 15A). MEL-18 depletion also persisted in reducing ER-alpha and PR expression and increased AKT activity in mice treated with E2 and / or tamoxifen (Fig. 4C and Fig. 15A). Moreover, mice bearing the MEL-18-overexpressing MDA-MB-468 TNBC cell tumor obtained sensitivity to tamoxifen therapy, but no difference in overall tumor growth between the control and the MEL-18-overexpressing cell xenograft 4D). In mice injected with MDA-MB-231 cells that exhibited faster tumor growth than MDA-MB-468 cells in the xenograft model, MEL-18 overexpression inhibited tumor growth by making tumors slightly more sensitive to tamoxifen 14C). Thus, these in vitro and in vivo data indicate that MEL-18 affects the response of both LUMINOUS breast cancer and TNBC to tamoxifen. Several estrogen-independent growth factors and their downstream targets, such as those of the PI3K / AKT pathway, have been reported to contribute to anti-estrogen resistance in breast cancer (Osborne CK, and Schiff R. Mechanisms of endocrine resistance in breast cancer. Annu Rev Med., 2011; 62 (233-47)). Since the present invention observed that AKT was constantly activated in MEL-18-silenced LUMINARY breast cancer cells regardless of E2 and / or tamoxifen treatment (FIGS. 5B and 15A), PI3K / I further investigated whether or not I was involved in mediating changes. In vivo treatment of xenograft tumors with MCF-7 cells by the PI3K inhibitor BKM120 demonstrated that MEL-18-silenced MCF-7 cell-based tumors were more effective than BKM120 for tamoxifen in comparison to control cell- (FIG. 15C). Moreover, the combined treatment of BKM120 and tamoxifen resulted in a synergistic anti-tumor effect on these tumors both in vitro and in vivo (Figs. 15B and 15C). Taken together, these results indicate that ER-α loss and AKT activation are required for MEL-18-loss-mediated tamoxifen resistance. We also found that subgroups of ER-α-positive patients (n = 103) with negative MEL-18 expression with tamoxifen were significantly worse than patients with positive MEL-18 expression, including poorer OS and DFS (OS, P = 0.034 and 0.048; DFS, P = 0.033 and 0.026, log-rank test and Cox regression, respectively) (Fig. 4E). Taken together, these findings indicate that continuous ER-α downregulation and activation of the proliferative signaling by MEL-18 loss confer resistance to estrogen deficiency and anti-hormone therapy, thereby characterizing hormone receptor-negative breast cancer do.

MEL-18 inhibits sumoylation of p53 and SP1 that can induce ESR1 expression.

Next, MEL-18 investigated the molecular mechanisms that regulate ER-alpha transcription. The proximal promoter region of ESR1, which is regulated by MEL-18, contains several binding sites for in vitro and transcription factors. However, no significant difference was observed between the control and MEL-18-silenced cells in the presence of known extracorporeal transformants of the ESR1 and PcG proteins or histone modifications including H3K27me3 and DNA methylation in the ESR1 promoter ( 16A-C). In addition, total expression of major ESR1 transcription factors, including P53, SP1 and c-Jun, did not change (Fig. 16D).

MEL-18 functions as an anti-SUMO E3 ligase by direct binding to both UBC9 and its substrates, and SUMOylation of transcription factors is primarily involved in transcriptional inhibition. Thus, the present invention has hypothesized that MEL-18 can regulate ESR1 transcription through inhibition of SUMOylation. We first determined whether p53 and SP1 reported as direct targets of UBC9 were new substrates for MEL-18. MEL-18 inhibited binding of SUMO-1 and p53 proteins directly in vitro, but did not inhibit SP1 protein (Fig. 17A-D), while SUMO analysis in vivo demonstrated that MEL-18 inhibiting the conjugation of SUMO-1 to both p53 and SP1 (Fig. 17E). Moreover, the endogenous SUMOylated p53 and SP1 proteins were inversely regulated by MEL-18 in both MCF-7 and MDA-MB-468 cells (Fig. 5A), suggesting that MEL-18 mediated through an indirect SUMO- Suggesting that SP1 SUMO conversion can be controlled. SUMOylated forms of CBP and c-Jun were not detected in these cells. These results indicate that MEL-18 directly or indirectly inhibits p53 and SP1 sumoylation. Because p53 and SP1 are both universal transcription factors, we induced our microarray results on MEL-18-silenced MCF-7 cells and the cooperative activity of p53 and SP1 to transcriptionally regulate their target genes Common target genes for MEL-18 and p53 / SP1 were determined by comparing the gene expression profiles of the GEO data set (Grinkevich et al; GSE13291) on MCF-7 cells treated with the small molecule RITA. Several breast cancer subtype-specific markers and genes involved in transcriptional regulation and cell proliferation were common targets of MEL-18 and p53 / SP1 (FIG. 5B and FIG. 18A). Since ESR1 was the target gene shared in these data sets, we next determined whether p53 and SP1 SUMO expression affects ESR1 transcription. The activity of the proximal ESR1 promoter was enhanced by the expression of the SUMO-deficient mature form of p53 (K386R) or SP1 (E18A) compared to their wild type (WT) expression in MCF-7 cells (Figure 18B) . Moreover, p53 K386R showed significant ESR1 promoter-binding ability compared to WT p53 (Fig. 18C). Inhibition of SUMOylation by treatment with ginseng acid, a SUMO inhibitor, also enhanced ESR1 promoter activity (Figure 18D) in TNBC cells with p53-point mutations (MDA-MB-468, R273H; MDA-MB-231, R280K) . Similarly, a decrease in ESR1 promoter activity due to MEL-18 knockdown in MCF-7 cells was ablated by expression of mature forms of p53 or SP1 (Fig. 5C). A synergistic effect was observed when p53 and SP1 mature were co-expressed. In agreement, the silencing of p53 or SP1 using siRNA in TNBC cells partially inhibited the MEL-18-induced ESR1 promoter activity, and the co-inhibition of p53 and SP1 completely abolished this inhibition (Fig. 18E). Moreover, the recruitment of p53 and SP1 to the ESR1 promoter was inhibited by MEL-18 knockdown in Luminal cells and by MEL-18 overexpression in TNBC cells (Fig. 5D). The binding of this promoter to c-JUN and CBP, which were not detectably SUMOylated in these cells, was not affected by MEL-18 (Fig. 19A). In addition, based on the microarray data of this example, the ability of p53 and SP1 to bind to the promoter of CDKN1A, a major target gene of p53, which was not targeted by MEL-18, was detected by the ESR1 promoter binding in MCF-7 after MEL- (FIG. 19B), suggesting that ESR1 is a preferential target in MEL-18-mediated coordination of SUMOylation. We also found that reduced sumoylation of p53 and SP1 induced by treatment with ginkgolan restored ER-alpha expression in MEL-18-silenced MCF-7 cells (Fig. 5E). Taken together, these data suggest that SUMO expression of the transcription factor p53 and SP1 due to MEL-18 loss compromised their recruitment to the ESR1 promoter, thereby reducing ER-α expression.

MEL- 18 is the SENP1 Ubiquitin-proteasome degradation by inhibiting the de-SUMO thereby vibrate the screen increases.

In order to further confirm the mechanism by which MEL-18 regulates sumoylation, the effect of MEL-18 on the expression of SUMO-related factors was tested. In MEL-18-silenced MCF-7 cells, the level of the 39-kDa SUMO-1-conjugated form of SUMO E2 enzyme UBC9 was increased, but the level of 18-kDa free form of UBC9 was decreased (Fig. 20A). In contrast, MEL-18 overexpression increased the expression of free forms of UBC9 and SUMO-1 in TNBC cells. Notably, the expression of SUMO-1 / centrin-specific protease 1 (SENP1) and the desaturase activity were positively regulated by MEL-18 (FIGS. 20A and B). These data suggest that MEL-18 enhances SENP1-mediated des sumoylation and inhibits SUMOylation by inhibiting UBC9-mediated SUMO-1 conjugation. Since SENP1 mRNA levels were not altered by MEL-18 (Fig. 6A), we next examined the mechanism by which MEL-18 modulates SENP1 expression at post-transcriptional levels. We have found that MEL-18 knockdown induces accelerated SENP1 protein degradation after treatment of MCF-7 with cycloheximide (CHX), a protein synthesis inhibitor (FIG. 6B). Moreover, treatment with the proteasome inhibitor MG132 restored SENP1 expression in these cells (Fig. 6C), and MEL-18 blocked both ubiquitinated SENP1 protein exogenously and endogenously as measured by in vivo ubiquitination assay (Figures 6D and E). Thus, these results suggest that MEL-18 loss promotes ubiquitin-mediated proteasome degradation of SENP1. To confirm the molecular mechanism of SENP1 protein stabilization by MEL-18, we next examined whether the BMI1 / RING1B ubiquitin ligase complex, which is negatively regulated by MEL-1, targets the SENP1 protein. As shown in Figure 6F, overexpression of RING1B (C51W / C54S) catalytic inactive mutants, unlike WTRING1G, restored SENP1 protein levels and consequently increased ER-alpha expression in MEL-18-silenced MCF-7 cells . A similar effect was also observed when the RING1B cofactor BMI-1 was silenced by siRNA in MCF-7 cells (Fig. 6G), suggesting that MEL-18 inhibited BMI-1 / RING1B, thereby inhibiting the ubiquitin-mediated proteasome of SENP1 Indicates prevention of decomposition.

Since SENP1 overexpression reverses MEL-18-depleted-mediated downregulation of ER-alpha in MCF-7 cells (Fig. 6H), we further validated the effect of its des sumoylation activity on SENP1 expression and hormone receptor expression did. SENP1 silencing by siRNA increased both sumoylation of p53 and SP1 and subsequently downregulated ER-alpha and PR expression at transcription level in WT MCF-7 cells (Fig. 21A-C). Moreover, the catalytically inactive mature (R630L / K631M) of SENP1 impaired des sumoylation of p53 and SP1 and did not increase ESR1 or PR transcription (Fig. 21D-F). These data demonstrate that MEL-18 inhibits the degradation of ubiquitin-proteasome of SENP1, thereby enhancing the desumoylation of p53 and SP1 and regulating ER-α and PR expression.

We also confirmed positive correlation between SENP1 protein expression and MEL-18 expression in 223 human breast tumors (Figure 22A, P = 0.001) and mouse xenograft models (Figures 22B and C). Furthermore, SENP1 negative correlated with TNBC (P = 0.001), ER-α negative (P <0.001), higher histological grade (P = 0.010), and larger tumor size (P = 0.032) .

Clinical pathological features
n
SENP1 expression P value
(Fisher project test)
voice positivity AJCC Phase 0.649 Step 1-II 164 88 (53.7%) 76 (46.3%) Step III-IV 59 29 (49.2%) 30 (50.8%) Tumor size 0.032 <5 cm 117 53 (45.3%) 64 (54.7%) > 5 cm 106 64 (60.4%) 42 (39.6%) Lymph node metastasis 0.350 voice 119 66 (55.5%) 53 (44.5%) positivity 104 51 (49.0%) 53 (51%) Histologic grade * 0.010 Grades 1-2 138 66 (47.8%) 72 (52.2%) Grade 3 54 37 (68.5%) 17 (31.5%) ER-alpha state <0.001 voice 97 64 (66.0%) 33 (34.0%) positivity 126 53 (42.1%) 73 (57.9%) PR status 0.080 voice 103 61 (59.2%) 42 (40.8%) positivity 120 56 (46.7%) 64 (53.3%) HER2 status (IHC) 0.735 voice 181 94 (51.9%) 87 (48.1%) positivity 42 23 (54.8%) 19 (45.2%) Molecular Classification ** 0.001 Luminal 125 53 (42.4%) 72 (57.6%) HER2-positive 29 17 (58.6%) 12 (41.4%) Triple-negative 53 37 (69.8%) 16 (30.2%)

* Invasive ductal carcinoma only.

** Based on ER-α, PR and HER2 status.

Multivariate analysis, however, showed that SENP1 expression was not a strong independent prognostic factor for survival (Table 7). Thus, these data indicate the importance of MEL-18-mediated SENP1 modulation in breast cancer progression and suggest SENP1 and MEL-18 as new markers of ER-α negative.

Univariate Multivariate HR 95% CI P value HR 95% CI P value DFS step
(I or II vs. III or IV) 3.917 2.247-6.831 <0.001 3.692 1.557-8.751 0.003 Grade (1 or 2 vs. 3) 0.979 0.504-1.900 0.949 LN transition 2.33 1.307-4.152 0.004 1.051 0.429-2.578 0.913 ER-α (negative vs. positive) 0.566 0.324-0.989 0.046 0.683 0.384-1.214 0.194 PR (voice versus positive) 0.692 0.397-1.206 0.194 HER2 (negative vs positive) 0.951 0.462-1.957 0.891 SENP1 (negative vs positive) 0.581 0.323-1.043 0.069 0.595 0.327-1.083 0.089 OS step
(I or II vs. III or IV) 4.874 2.406-9.876 <0.001 7.346 2.126-25.376 0.002 Grade (1 or 2 vs. 3) 1.001 0.443-2.260 0.998 LN transition 2.386 1.150-4.949 0.019 0.590 0.164-2.123 0.419 ER-α (negative vs. positive) 0.509 0.251-1.031 0.061 PR (voice versus positive) 0.528 0.261-1.071 0.077 HER2 (negative vs positive) 0.821 0.316-2.133 0.686 SENP1 (negative vs positive) 0.722 0.353-1.478 0.373 0.688 0.336-1.409 0.306

* Cox regression risk model

HR = Hazard Ratio; CI = confidence interval

Review

The present invention demonstrates that MEL-18 can be used as a predictor of triple-negative and anti-hormonal therapy resistance. Furthermore, in the present invention, a novel mechanism of controlling the ESR1 gene was confirmed by MEL-18. MEL-18 inhibits sumoylation of the ESR1 transcription factors p53 and SP1 by inhibiting SUMO-1 conjugation or de-SUMOylation through degradation of ubiquitin-proteasomes in SENP1, which promotes ESR transactivation RTI ID = 0.0 &gt; 7A). &Lt; / RTI &gt; Taken together, these results indicate that SUMO-mediated hormone receptor modulation by MEL-18 is important for breast cancer progression.

The data according to the above example suggests that hormone receptor-dependent loss-inducing deficiency of MEL-18 is an important event in the progression of breast cancer (Fig. 7B). MEL-18 loss can activate an alternative estrogen-independent signaling pathway that can achieve hormone independence. Overexpression of receptor tyrosine kinase (RTK) and downstream signaling pathways of the RTK, such as the PI3K / AKT pathway, are closely linked to estrogen independence and endokrin therapy resistance in breast cancer. Indeed, the data according to this example demonstrate that the inhibition of the PI3K / AKT pathway results in the maintenance of the MEL-18 loss-mediated tamoxifen resistance . Thus, the present invention suggests that sustained downregulation of ER-α and activation of RTK-related signaling by MEL-18 may confer estrogen independence and anti-estrogen therapy resistance. Recent studies by the present inventors have shown that MEL-18 loss induces the expansion of CD44 ⁺ / CD24 ^- stem-like cell populations and EMT, which is characteristic of hormone-independent basal-type breast cancer (Won HY , J J, Shin JH, Park JH, Nam JS, Kim HC, and Kong G. Loss of Mel-18 enhances breast cancer stem cell activity and tumorigenicity through activating Notch signaling mediated by the Wnt / TCF pathway. 26 (12): 5002-13; Park JH, Lee JY, Shin DH, Jang KS, Kim HJ and Kong G. Loss of Mel-18 induces tumor angiogenesis through enhancing the activity and expression of HIF-1alpha mediated by the PTEN Inhibitors of INK4a / ARF-1 and / or PI3K / Akt pathway negatively regulate Mel-18 / Oncogene. 2011; 30 (45): 4578-89; Lee JY, Jang KS, Shin DH, Oh MY, Kim HJ, Kim Y, 2008; 68 (11): 4201-9; Lee JY, Park MK, Park JH, Lee HJ, Shin DH, Kang Y, Lee CH, and Kong G. Loss of the polycomb protein Mel-18 enhances the epithelial-mesenchymal transition by ZEB1 and ZEB2 expression through the downregulation of miR-205 in breast cancer. Oncogene. 2014; 33 (10): 1325-35). Moreover, some studies have demonstrated that MEL-18 is strongly involved in the regulation of some molecules associated with basal-type cancer, including p53, PTEN, PI3K, Wnt, Notch, and miR-205 or TNBC. For example, a high percentage of TNBC cases lack PTEN expression, and MEL-18 loss has also been shown to induce PTEN down regulation and PI3K / AKT activation. The loss of p53 function is characteristic of TNBC, and MEL-18 is associated with p53 function by activating p53 transcription even when p53 is expressed in mature form in TNBC cells. In addition, this evidence suggests that MEL-18 may play an important role in the regulation of luminal and basal-type cell fate in mammary glands, and this possibility should be further tested using a genetically engineered MMTV mouse model. Taken together, it can be seen that the loss of MEL-18 in hormone-dependent breast cancer aggravates the aggressiveness of breast cancer by altering the expression or activity of hormone receptors.

The present invention provides the first evidence for the SUMO-related transcriptional regulation of ESR1 by MEL-18. Although the effect of sumoylation on p53 transcriptional activity is controversial, it can be seen that, according to the present invention, p53 SUMOylation is associated with loss of its transcriptional activity. p53 regulates ESR1 transcription by forming transcriptional activation complexes with other transcription factors including SP1, c-JUN and CBP. In the present invention, p53 and SP1 are independent transcriptional activation factors of ESR1, and the regulation of sumoylation of both p53 and SP1 by MEL-18 does not affect the binding of c-JUN or CBP to the ESR1 promoter, Lt; RTI ID = 0.0 &gt; ESR1 &lt; / RTI &gt; promoter. Thus, these facts demonstrate the importance of the MEL-18-mediated modification of p53 and SP1 proteins in the regulation of ESR1 transcription. Because mutant p53 (R273H and R280K) retain their function, targeting the SUMOylation pathway to regulate ESR1 transcription may be effective in both wild-type and mutant p53-expressing cells. Furthermore, the present invention explains the mechanism by which MEL-18 regulates the sumoylation process. That is, the present invention shows that MEL-18 is involved in the indirect regulation of sumoylation through regulation of SENP1 protein expression. Moreover, the present invention shows that SENP1 is a novel ubiquitination target of MEL-18 containing the PRC-1 complex and is also important for ESR1 regulation by promoting desumoylation of the transcription factor of ESR1. However, based on survival analysis, SENP1 is clinically less relevant than MEL-18, presumably because SENP1 is a downstream target of MEL-18 in the regulation of ER-α. Further, according to the present invention, the inhibition of sumoylation through overexpression of MEL-18 and SENP1 in combination with a prodrug formulation provides the possibility of promoting ESR1 re-expression in hormone receptor-negative breast cancer therapies.

The data according to the present invention support the clinical significance of MEL-18 in human breast cancer. Previous studies have demonstrated that MEL-18 expression is lower in human breast cancer tissue than in normal breast tissue (Riis ML, Luders T, Nesbakken AJ, Vollan HS, Kristensen V, and Bukholm IR. Expression of BMI-1 and Mel -18 in breast tissue - a diagnostic marker in patients with breast cancer. 2010; 10 (686; Guo BH, Zhang X, Zhang HZ, Lin HL, Feng Y, Shao JY, Huang WL, Kung HF, and Zeng MS. Low expression of Mel-18 predicts poor prognosis in patients with breast cancer. Annals of oncology: official journal of the European Society for Medical Oncology / ESMO. 2010; 21 (12): 2361-9; Lee JY, Jang KS , Shin DH, Oh MY, Kim HJ, Kim Y, and Kong G. Mel-18 negatively regulates INK4a / ARF-independent cell cycle progression via Akt inactivation in breast cancer. Cancer Res 2008; 68 (11): 4201-9 ), The clinical significance of MEL-18 in different breast cancer subtypes has not been assessed.

The present invention demonstrated negative correlation of MEL-18 protein and mRNA levels with TNBC subtype based on IHC analysis of breast cancer samples and gene expression profiles of multiple independent microarray data sets from various breast cancer populations. Furthermore, although the correlation between expression of MEL-18 and the hormone receptor is still controversial, considering that Guo et al. Failed to detect any association between MEL-18 and ER-α expression in their breast cancer cohort (Guo BH, Zhang X, Zhang HZ, Lin HL, Feng Y, Shao JY, Huang WL, Kung HF, and Zeng MS. Low expression of Mel-18 predicts poor prognosis in patients with breast cancer. The data presented in the present invention and these microarray data sets are used to determine MEL-18 expression and other Luminal marker expression of ER-alpha human breast cancer (see, for example, &lt; RTI ID = 0.0 & Of the population.

Further, the clinical data presented in the present invention demonstrate that MEL-18 is a more valuable prognostic marker of LUMINARY breast cancer than TNBC. The limited significance of the difference in survival rate between the high and low expression groups of MEL-18 in patients with TNBC or basal breast cancer subtypes is due to the exclusively downregulation of MEL-18 in the TNBC group and its lack of downstream target ER- Or due to the molecular heterogeneity and highly aggressive nature of TNBC. Notably, breast cancer patients with MEL-18 loss were less likely to achieve therapeutic benefit from tamoxifen therapy. Resistance to endocrane therapy is a major complication of breast cancer therapy, and ER-α is currently the most important clinical biomarker to predict the outcome of endoclone therapy. Several studies have demonstrated that downregulation of ER-α results in tamoxifen resistance in ER-α-positive breast cancer (Ahn BY, Elwi AN, Lee B, Trinh DL, Klimowicz AC, Yau A, Chan JA, A, and Kim SW. Genetic screen identifies insulin-like growth factor binding protein 5 as a modulator of tamoxifen resistance in breast cancer Cancer Res. 2010; 70 (8): 3013-9; Parra-Palau JL, Pedersen K, Peg V, Scaltriti M, Angelini PD, Escorihuela M, Mancilla S, Sanchez Playa, Ramon YCS, Baselga J, et al A major role of p95 / 611-CTF, a carboxy-terminal fragment of HER2, of the estrogen receptor in HER2-positive breast cancers. Cancer Res. 2010; 70 (21): 8537-46). In addition, several clinical trials (NCT01194908) are in progress to re-activate ER-α in patients with TNBC and restore the therapeutic effect of tamoxifen. In this context, data according to the present invention show that overexpression of MEL-18 confers tamoxifen sensitivity to TNBC cells, which is a potential therapeutic target for restoring TNBC sensitivity to anti-hormonal therapy, . Thus, according to the present invention, it can be seen that MEL-18 acts as a novel modulator of the important tumor suppressor and ER-a and can be used as a new prognostic marker for the outcome of tamoxifen treatment.

Taken together, the present invention demonstrated that MEL-18 functions as a regulator of SUMO-dependent hormone receptor transcription and is a novel prognostic marker and predictor of TNBC response to anti-hormone therapy. Thus, MEL-18 is a promising molecular target for altering the resistance of breast cancer to anti-hormone therapy.

<110> Industry-University Cooperation Foundation Hanyang University <120> Biomarker for diagnosis and treatment of antiestrogen-resistant          or triple negative breast cancer and composition comprising the          same <130> JKP-0440 <160> 2 <170> Kopatentin 2.0 <210> 1 <211> 1035 <212> RNA <213> human mel-18 <400> 1 atgcatcgga ctacacggat caaaatcaca gagctgaacc cccacctcat gtgtgccctc 60 tgcggggggt acttcatcga cgccaccact atcgtggagt gcctgcattc cttctgcaaa 120 acctgcatcg tgcgctacct ggagaccaac aaatactgcc ccatgtgtga cgtgcaggtc 180 cataaaaccc ggccgctgct gagcatcagg tctgacaaaa cacttcaaga cattgtctac 240 aaattggtcc ctgggctttt taaagatgag atgaaacggc ggcgggattt ctatgcagcg 300 taccccctga cggaggtccc caacggctcc aatgaggacc gcggcgaggt cttggagcag 360 gagaaggggg ctctgagtga tgatgagatt gtcagcctct ccatcgaatt ctacgaaggt 420 gccagggacc gggacgagaa gaagggcccc ctggagaatg gggatgggga caaagagaaa 480 gcctgaccg ctccgcaaca agatggatgt gcccagcaag tacaaggtgg aggttctgta cgaggacgag 600 ccactgaagg aatactacac cctcatggac atcgcctaca tctacccctg gcggcggaac 660 gggcctctcc ccctcaagta ccgtgtccag ccagcctgca agcggctcac cctagccacg 720 gtgcccaccc cctccgaggg caccaacacc agcggggcgt ccgagtgtga gtcagtcagc 780 gacaaggctc ccagccctgc caccctgcca gccacctcct cctccctgcc cagcccagcc 840 accccatccc atggctctcc cagttcccat gggcctccag ccacccaccc tacctccccc 900 actccccctt cgacagccag tggggccacc acagctgcca acgggggtag cttgaactgc 960 ctgcagacac catcctccac cagcaggggg cgcaagatga ctgtcaacgg cgctcccgtg 1020 ccccccttaa cttga 1035 <210> 2 <211> 344 <212> PRT <213> human mel-18 <400> 2 Met His Arg Thr Thr Arg Ile Lys Ile Thr Glu Leu Asn Pro His Leu   1 5 10 15 Met Cys Ala Leu Cys Gly Gly Tyr Phe Ile Asp Ala Thr Thr Ile Val              20 25 30 Glu Cys Leu His Ser Phe Cys Lys Thr Cys Ile Val Arg Tyr Leu Glu          35 40 45 Thr Asn Lys Tyr Cys Pro Met Cys Asp Val Gln Val His Lys Thr Arg      50 55 60 Pro Leu Leu Ser Ile Arg Ser Asp Lys Thr Leu Gln Asp Ile Val Tyr  65 70 75 80 Lys Leu Val Pro Gly Leu Phe Lys Asp Glu Met Lys Arg Arg Arg Asp                  85 90 95 Phe Tyr Ala Ala Tyr Pro Leu Thr Glu Val Pro Asn Gly Ser Asn Glu             100 105 110 Asp Arg Gly Glu Val Leu Glu Gln Glu Lys Gly Ala Leu Ser Asp Asp         115 120 125 Glu Ile Val Ser Leu Ser Ile Glu Phe Tyr Glu Gly Ala Arg Asp Arg     130 135 140 Asp Glu Lys Lys Gly Pro Leu Glu Asn Gly Asp Gly Asp Lys Glu Lys 145 150 155 160 Thr Gly Val Arg Phe Leu Arg Cys Pro Ala Ala Met Thr Val Met His                 165 170 175 Leu Ala Lys Phe Leu Arg Asn Lys Met Asp Val Ser Ser Lys Tyr Lys             180 185 190 Val Glu Val Leu Tyr Glu Asp Glu Pro Leu Lys Glu Tyr Tyr Thr Leu         195 200 205 Met Asp Ile Ala Tyr Ile Tyr Pro Trp Arg Arg Asn Gly Pro Leu Pro     210 215 220 Leu Lys Tyr Arg Val Gln Pro Ala Cys Lys Arg Leu Thr Leu Ala Thr 225 230 235 240 Val Pro Thr Pro Ser Glu Gly Thr Asn Thr Ser Gly Ala Ser Glu Cys                 245 250 255 Glu Ser Val Ser Asp Lys Ala Ser Ser Ala Thr Leu Pro Ala Thr             260 265 270 Ser Ser Seru Pro Ser Ser Ala Thr Ser Ser His Ser Ser Ser Ser         275 280 285 Ser His Gly Pro Pro Ala Thr His Pro Thr Ser Pro Thr Pro Pro Ser     290 295 300 Thr Ala Ser Gly Ala Thr Thr Ala Ala Asn Gly Ser Seru Asn Cys 305 310 315 320 Leu Gln Thr Pro Ser Ser Thr Ser Arg Gly Arg Lys Met Thr Val Asn                 325 330 335 Gly Ala Pro Val Pro Pro Leu Thr             340

Claims (17)

A composition for diagnosing antihormonal and triple-negative breast cancer induced by sumoylation of the ESR1 transcription factors p53 and SP1, comprising an agent for measuring the expression level of the mRNA of the Mel-18 gene or a protein thereof. The method according to claim 1,
Wherein the mRNA of the Mel-18 gene is a nucleic acid sequence represented by SEQ ID NO: 1. 2. The composition for diagnosing antihormonal and triple-negative breast cancer according to claim 1, The method according to claim 1,
Wherein the Mel-18 protein is the amino acid sequence of SEQ ID NO: 2. 2. The composition of claim 1, wherein the Mel-18 protein is an amino acid sequence of SEQ ID NO: 2. The method according to claim 1,
Wherein the agent for measuring the expression level of the mRNA or the protein of the Mel-18 gene is an antibody specific to the Mel-18 protein. 5. The method of claim 4,
Wherein the antibody is a monoclonal antibody or a polyclonal antibody specific to a Mel-18 protein. The method according to claim 1,
Wherein the agent for measuring the mRNA expression level of the Mel-18 gene is an antisense oligonucleotide complementary to the mRNA of the Mel-18 gene, a primer or a probe, and a composition for diagnosing antihormonal and triple-negative breast cancer. An anti-hormonal and triple-negative breast cancer diagnostic kit induced by SUMO expression of the ESR1 transcription factors p53 and SP1, comprising the composition according to claim 1. In order to provide information necessary for the diagnosis of antihormonal resistance and triple-negative breast cancer induced by the SUMO-induction of the ESR1 transcription factors p53 and SP1, the mRNA or protein of the Mel-18 gene was detected from the patient's sample A method for detecting markers for the diagnosis or prognosis of anti-hormonal and triple-negative breast cancer induced by SUMO expression of the ESR1 transcription factors p53 and SP1. 9. The method of claim 8,
Wherein the sample is at least one sample selected from the group consisting of tissue, cells, blood, serum, plasma saliva, and urine of a patient, and a method for detecting a marker for analyzing a diagnosis or prognosis of an antihormonal agent and a triple-negative breast cancer. 9. The method of claim 8,
Measuring the level of expression of the mRNA of the Mel-18 gene or the protein thereof from the patient sample, and measuring the expression level of the mRNA or the protein of the Mel-18 gene in the mRNA of the Mel-18 gene or the protein thereof And comparing the expression level of the marker with the level of expression of the marker. The method for detecting a marker for the diagnosis or prognosis of an anti-hormonal agent and a triple-negative breast cancer. 11. The method of claim 10,
The method for measuring the expression level of the mRNA of the Mel-18 gene is characterized by reverse transcriptase polymerase, competitive reverse transcriptase polymerase, real-time reverse transcriptase polymerase, RNase protection assay, northern blotting or DNA chip And a marker for analyzing the diagnosis or prognosis of triple-negative breast cancer. 11. The method of claim 10,
Methods for measuring the expression level of the Mel-18 protein include Western blotting, ELISA, radioimmunoassay, radioimmunoassay, Oucheronian immunodiffusion, rocket immunoelectrophoresis, tissue immuno staining, immunoprecipitation assay, complement fixation assay, FACS or a protein chip. 2. A method for detecting a marker for the diagnosis or prognosis of an anti-hormonal agent and a triple-negative breast cancer. A pharmaceutical composition for the treatment of anti-hormonal and triple-negative breast cancer induced by SUMO-induction of the ESR1 transcription factors p53 and SP1, which comprises an anti-hormonal therapeutic agent for breast cancer treatment and a PI3K inhibitor as an active ingredient. delete delete 14. The method of claim 13,
Wherein the anti-hormone therapeutic agent is tamoxifen. 14. The method of claim 13,
Wherein said PI3K inhibitor is BKM120.

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