Metformin induced apoptosis of nasopharyngeal carcinoma cell CNE-1 by regulating miR-let-7a and IGF-1R / 医学研究生学报

ABSTRACT

Objective research the effects of metformin on proliferation and apoptosis in nasopharyngeal carcinoma cell CNE-1 and investigate the role of miR-let-7a、IGF-1R in it. Methods The nasopharyngeal carcinoma cell CNE-1 was treated with different concentrations of metformin for 24h, then the proliferation activity of cell was detected by CCK8 method; the apoptosis rate of cell was measured by flow cytometry; the expression levels of bcl-2、bax and IGF-1R mRNA and miR-let-7a were detected by real-time quantitative PCR; the expression level of IGF-1R protein was detected by Western blot. Results Compared with the control group, the cell proliferation activity of metformin group decreased(P<0.05), and it gradually decreased along with the increase of metformin concentration. The cell apoptosis rate of metformin group increased(P<0.05 except for the 5 mmol/L group), and it gradually increased along with the increase of metformin concentration. The expression levels of bax mRNA and miR-let-7a were up-regulated in the metformin group(P<0.05), while the expression levels of bcl-2 mRNA,IGF-1R mRNA and IGF-1R protein were decreased(P<0.05). Conclusion Metformin could inhibit the proliferation and induce apoptosis of CNE-1. The mechanism maybe related to the up-regulation of miR-let-7a and down-regulation of IGF-1R.