Metformin inhibits proliferation and promotes apoptosis of human cervical squamous cell carcinoma cell lines SiHa and CaSki

Abstract

Objective To investigate the effects and mechanism of metformin(Met) on the proliferation of cervical squamous cell carcinoma. Methods CCK-8 method was used to check the proliferation of cells lines SiHa and CaSKi, the semi inhibitory concentration of metformin (IC50) was calculated as well.The cell cycle and apoptosis were examined by flow cytometry, and the expression of AMPK-mTOR signal pathway related proteins was detected by Western blot. Results With the increase of drug concentration and time, the cell proliferation rate decreased(P＜0.05).The IC50 concentrations of SiHa cells at 48 and 72 h were (50.95±2.63) and (21.39±5.23) mmol/L respectively, and those of CaSki cells were (9.98±1.63) and (7.47±2.09)mmol/L, resepectively. The content of G2/M phase cells decreased and S phase cells increased in Met group (P＜ 0.05). The apoptosis rate of Met group was higher than that of control group (P＜ 0.05). The expression of p-AMPK in the Met group was higher than that in the control group, while p-S6K and p-4E-BP1 were lower(P＜ 0.05). Conclusions The inhibitory effect of metformin on the proliferation of cervical squamous cell carcinoma lines may be related to the mechanism of promoting apoptosis,blocking cell cycle at S phase and activation of AMPK-mTOR signal pathway.

Keywords

• metformin|cervical squamous cell carcinoma cell lines|cell cycle|apoptosis|mammalian target of rapamycin