Effect of miR-145 on MCF-7 breast cancer cells by regulating disintegrin-metalloproteinase-17 / 医学研究生学报

ABSTRACT

Objective MicroRNA-145 (miR-145) is underexpressed in breast cancer. The study aimed to explore the regulatory effect of miR-145 on breast cancer MCF-7 cells by investigating the association of miR-145 with ADAM17 and EGFR. Methods The MCF-7 breast cancer cells were divided into three groups the transfection group (transfected with microRNA-145 mimics), the control group (without transfection) and the nonsense sequence group (transfected with nonsense microRNA). MTT, transwell and real-time quantitative fluorescence polymerase chain reaction(qPCR) were respectively used to detect the proliferative capacity, invasive ability and expression of MCF-7 breast cancer cells after the transfection of miR-145 in three groups. ADAM17 and EGFR mRNA and protein levels in three groups of breast cancer MCF-7 cells were detected by qPCR and western blot. Results The results of qPCR showed that the relative expression of miR-145 was significantly higher in transfection group (13964.33±1265.30) than those in control group (1.00±0.05) and nonsense sequence group (1.03±0.15) and the difference was statistically significant (P<0.01); the expression of ADAM17 mRNA in transfection group (1.71±0.08) was significantly higher than that in control group (1.00±0.07) and the difference was statistically significant (P<0.01). Compared with the nonsense sequences at 24 h, 48 h, and 72 h, the inhibition rate of MCF-7 in transfection group was significantly increased (P<0.01). The results of transwell invasion showed that the number of transmembrane cells in transfection group [(56.20±2.17)/field] was significantly lower than those in control group [(92.80±3.90)/field] and nonsense sequence group [(91.80±4.97)/field of view ] (P < 0.01). Western blot results showed that the protein content of ADAM17 and EGFR in transfection group was significantly lower than those in the control group and the nonsense sequence group (P<0.01). Conclusion MiR-145 inhibits the proliferation and invasion of breast cancer MCF-7 cell line by acting on the ADAM17-EGFR signaling pathway.