Research On The Expression And Biological Role Of VEGF And MTDH In Triple-negative Breast Cancer

Background&Objective:Breast cancer is the most common malignancy of women, the report shows there are about1,380,000new cases in the world each year, while approximately400,000patients succumb to breast cancer each year. According to the different molecular classification, breast cancer has various treatment and prognosis. Triple-negative breast cancer (TNBC) is a type of highly malignant, powerful invasion and poor prognosis. The treatment of TNBC is limited due to its expressions of estrogen receptor, progesterone receptor and epidermal growth factor receptor are negative. Recent studies have shown that Vascular endothelial growth factor(VEGF) are involved in the growth and metastasis of breast cancer as the most important factors in angiogenesis. Targeted drugs to inhibit VEGF have been used in clinical cancer therapy, receiving good curative effect. Axitinib is the latest tyrosine kinase antagonist inhibitors to antagonism VEGF receptors, approved the listing by U.S. Food and Drug Administra-tion in2012. Mctadherin (MTDH) is proved to be an oncogene in breast cancer, promoting breast cancer cell proliferation, apoptosis, migration, invasion, and mediating resistance to chemotherapy. The basic research support it as a potential target to treatment for breast cancer. There are few report about the expression and the relationship between VEGF and MTDH in TNBC, whether to commit VEGF and MTDH as new targets for the treatment of TNBC. This study is to investigate the relationship between the expression of VEGF and MTDH in TNBC tissue and clinicopathological features, the influence of VEGF receptor inhibitors axitinib on proliferation, apoptosis, MTDH expression of TNBC cell lines MDA-MB-231, the influence of axitinib joint epirubicin on proliferation of MDA-MB-231, to clarify whether the VEGF and MTDH synergistically promote the development of TNBC, and provide new ideas in clinical treatment of TNBC.Methods:1. Collecting specimens and clinical data of TNBC patients, utilized immunohistochemical methods to detect the expression of VEGF and MTDH, and analyzed the relationship between clinicopathological features and the expression.2. MTT assay detected the influence of axitinib alone and in combination with epirubicin to proliferation of TNBC cells MDA-MB-231.3. Annexin V/PI double staining detected the influence of axitinib on apoptosis of MDA-MB-231cells.4. Reverse transcription PCR (RT-PCR) detected the role of axitinib on expression of MTDH mRNA of MDA-MB-231cells.Results:1. The expression of VEGF and MTDH in TNBC was54.7%,62.7%, their expression in benign breast tissue was20.7%,27.6%, the differences were statistically significantly. The expression of VEGF and MTDH had relevance in TNBC (r=0.349, P=0.002).The expression of VEGF was significantly associated with lymph node metastasis, tumor grade in triple-negative breast cancer (P<0.05). The expression of MTDH was significantly associated with tumor size, lymph node metastasis, tumor grade, clinical stage, disease-free survival and p53expression in TNBC (P<0.05).2. Axitinib and epirubicin acted on MDA-MB-231cells respectivly, the difference of inhibition rates were statistically significant compared with the control group and among the dosing groups. The inhibition rate of two drugs used together was significant higher than used respectivly(P<0.05, Q>1.15).3. The apoptosis rates of Axitinib0μmol/L0.5μmol/L,1μmol/L,2μmol/L inducing MDA-MB-231cells were 6.63±0.74%,11.56±1.20%,15.84±0.98%, the difference was statistically significantly between dosing groups and control group and between each two dosing groups.4.The MTDH mRNA relative expression levels of axitinib0μmol/L,0.5μmol/L,1μmol/L inducing MDA-MB-231cells were1.38±0.09,1.06±0.13,0.75±0.05, the difference was statistically significance between each two groups.Conclusion:1. VEGF and MTDH both highly expresse in specimens of TNBC patients, their positive expression have relevance.2. The expression of VEGF is significantly related with lymph node metastasis and tumor grade in TNBC; the expression of MTDH is significantly related with with tumor size, lymph node metastasis, tumor grade, clinical stage, disease-free survival and p53in TNBC.3. Axitinib and epirubicin can inhibite MDA-MB-231breast cancer cell proliferation respectively in a dose-dependent manner, and they have synergistic effect on the combination.4. Axitinib can induce apoptosis, reduce expression levels of MTDH mRNA of MDA-MB-231cells, they both have a dose-dependent effect.