Effects Of Epithelial-Mesenchymal Transition And Invasion And Migration Of IL-6 On Breast Cancer MCF-7 Cell

Objective:To study the qualitative impact of the IL-6 on migration and invasion of MCF-7 cell lines in breast cancer and to discuss its mechanism of action.Methods:l.MTT method was used to detect different concentrations of IL-6 (25,50, 100 ng/mL) in treatment group and control group (0 ng/mL) in breast cancer MCF-7 cell proliferation at 24,48,72 hours;2. In vitro migration ability of MCF-7 cell in breast cancer was observed by using IL-6 concentration level after 48h (25,50,100 ng/mL) in treatment group and (0 ng/mL)in control group with cell scratch experiment;3. To study the invasive potential of MCF-7cell in breast cancer, we used Transwell Chamber Experiment by testing different concentration of IL-6 (25, 50,100 ng/mL) 48h after treatment and control group (0 ng/mL)；4. RT-PCR assay was used for detection of different concentrations of IL-6 (25,50,100) after 48h and the control group (Ong/mL) related to MCF-7 cells in the epithelial marker E-cadherin marker, Vimentin, invasion and migration of MMP-9 mRNA levels;5. Western Blot Assay was used to detect the different concentrations of IL-6 (25,50,100 ng/mL) 48h and the control group (Ong/mL) related to qualitative level of MCF-7 cells and epithelial marker E-cadherin, Vimentin, invasion and migration of MMP-9 protein expression.6. Using immunohistochemical assay within the group of patients with breast cancer,detect IL-6 and EMT-associated protein E-cadherin, Vimentin expression in the tissue.Results:1.With different concentrations of IL-6 (25,50 and 100 ng/ml) OD of the treatment group (490) values are increased compared with the control group (0 ng/ml), with the increased IL-6 concentration with time, show a dose-effect relationship (p<0.05).2. Different concentrations of IL-6 (25,50, and 100ng/ml) with migration distance of breast cancer MCF-7 cell line after 48h were (18.97±0.31), (23.93 ±0.25) and (29.30±0.46) mm, respectively while the control group (0 ng/ml) MCF-7 of breast cancer cell migration distance (15.20±0.40) mm. Different concentrations of IL-6 (25,50 and 100 ng/ml) MCF-7 breast cancer cell migration distance in the treatment group compared with the control group (0 ng/ml) significantly increased with MCF-7 breast cancer cell migration distance, and with the increasing concentration of IL-6, there was statistical difference (p <0.05).3.The different concentrations of IL-6 (25,50, 100ng/mL) MCF-7 of 48h through a Matrigel glue, were (43.00±3.61), (68.00±3.00) and (84.33±2.52), respectively, while the control group (0 ng/ml) number of MCF-7 cells through Matrigel glue was (28.00±2.65). Different concentrations of IL-6 (25,50 and 100 ng/ml) through Matrigel MCF-7 cells in the treatment group were significantly increased than the control group (0 ng/ml) with the increasing concentration of IL-6 with more Matrigel MCF-7 counts, there was statistical difference (p<0.05).4. In the different concentration of 48h IL-6 (25、50、100ng/mL) treatment group, the expression of E-cadherin mRNA were 0.76±0.074、 0.52±0.087 and 0.45±0.048 respectively. The Vimentin mRNA expressed as 1.15±0.111、2.71±0.096 and 3.11±0.200,while MMP-9 mRNA expressed 1.23±0.039、2.25±0.170 and 3.59±0.261 respectively. Compared with control group (Ong/mL), the expression of E-cadherin mRNA in breast cancer MCF-7 cell in IL-6 treated group was lower and that of Vimentin and MMP-9 mRNA expressions were higher(P<0.05).5. By different concentration of IL-6 (25,50,100 ng/mL) treatment after 48 h, IL-6 (25,50,100 ng/mL) in the treatment group E-cadherin were 3.45± 0.340,2.58±0.141 and 2.04± 0.172, respectively. Relative expression of Vimentin protein respectively 2.08±0.121,2.46±0.068 and 3.22±0.520, relative expression of MMP-9 protein 1.03±0.214,1.90±0.145 and 2.22± 0.191, respectively. Compared with the control group (0 ng/mL), the IL-6 (25, 50,100 ng/mL) after treatment of breast cancer in the MCF-7 cell E-cadherin protein expression were lower (P< 0.05), while expression of Vimentin and MMP-9 were higher (P<0.05).6.Expression of IL-6, E-cadherin, Vimentin in breast cancer tissue is higher than normal tissue; expression of IL-6, Vimentin in patients with Axillary lymph node metastasis is higher than those without a high axillary lymph node metastasis, E-cadherin is lower than those without axillary lymph node metastases; expression of IL-6, E-cadherin, Vimentin is related with tumor size, TNM stage, histological grade, lymph node metastasis, ER, PR, and has nothing to do with age, menopause or not, there is significant correlation between the expression of all three. With lymph node metastasis, high TNM stage, high histological grade, ER and PR-negative breast cancer patients, expression of IL-6 and Vimentin positive rate increased, Ecadherin positive rate decreased (P <0.05).Conclusion:Changes in cell morphology and related gene transcription and translation level certificate, IL-6 can induce the EMT MCF-7 cell breast cancer, and to promote the proliferation and migration in vitro.