Effect of the mTOR inhibitor everolimus on the malignant behavior of cervical cancer SiHa cells

WU Qiufang; TANG Zhouzhou; ZHANG Dingfu

Abstract：Objective To investigate the effect of an mTOR pathway inhibitor everolimus( EVE) on the proliferation, apopto?sis and epithelial mesenchymal transition( EMT) of human cervical cancer SiHa cells. Methods After being cultured in normal cul?ture, the SiHa cells were treated with EVE at final concentrations of 1, 10 and 100 μmol/L. The cell proliferation was measured by methyl thiazolyl tetrazolium in the control group and different concentrations of EVE at 24, 48, 72 and 96 h after exposure. The early?and late?apoptosis rate was measured by Annexin V/PI double staining via flow cytometry, and the apoptosis related gene expression ( Bax, Bad and Bcl?2) was assessed by real?time fluorescence quantitative polymerase chain reaction. Western blotting and immunoflu?orescence assay were used to detect the levels of EMT related marker molecules, including E?cadherin( E?cad) , Fibronectin( FN) and Vimentin(Vim) at 96 h after EVE exposure. Results EVE had inhibitory effect on the proliferation of SiHa cells in the range of 1?100μmol/L in a dose?and time?dependent manner. Except for 1μmol/L at 24 h, the proliferation inhibition rates of the remaining concen?tration and action times were higher than that of the control group( P<0?05) . Compared with the control group, EVE treatment for 96 h could dose?dependently increase the apoptosis rate and mRNA levels of Bax and Bad but decrease Bcl?2 level(P<0?05). Compared with the control group, the level of E?cad was increased but the levels of Vim and FN were decreased after treatment with different con?centrations EVE for 96 h( P<0?05) . Conclusion Blocking mTOR pathway by EVE has a toxic effect on cervical cancer SiHa cells, which not only inhibit the proliferation and induce apoptosis, but may be related to the inhibition of EMT process.