宫颈癌SiHa/DDP细胞系EMT相关分子表达研究

OBJECTIVE Epithelial-to-Mesenchymal transition is a biologic process in which epithelial cells lose their polarity and acquire the characteristics of mesenchymal cells,which is associated with resistance to a variety of antitumor drugs.We established a cisplatin-resistant human cervical cancer cell line SiHa/DDP.This study aimed to establish a correlation model between EMT and cisplatin chemoresistant in cervical cancer,the expression of EMT related molecules was compared with that of parental cells which may help to study the chemoresistant in cervical cancer.METHODS The cisplatin-resistant cervical cancer line SiHa/DDP was developed from the parental SiHa cells that was subjected to gradient exposure to cisplatin.The resistance index(RI) was evaluated by MTT analysis.The ability of migration and invasion in vitro was detected by wound healing assays and transwell assays.The expression of EMT associated gene was assessed with Real Time PCR and Western bloting.RESULTS SiHa/DDP cell line was established and RI to DDP was 4.48.Cell invasion and migration ability was higher than that of parental SiHa cells [wound healing percentage:(64.89±3.91)% vs (17.11±4.49)%,t=-12.738,P=0.001; number of invasion cells:(281.33±27.74) vs (150.33±22.3),t=-6.375,P=0.003].Compared to parental SiHa cells,SiHa/DDP had over-expression in Vimentin,N-cadherin and Snail,downregulation in E-cadherin,Nano and Oct4 at mRNA level.SiHa was exposed to 0.4 μmoL/L DDP,downregulation of E-cadherin and upregulation of Snail were observed at the protein level.When the concentration of DDP was stabilized to 2 μmoL/L,down-regulation of E-cadherin was observed,but Snail protein disappeared.Otherwise,increased expression of GSK-3β was observed.CONCLUSIONS Acquired resistance to cisplatin is associated with EMT in cervical cancer cell line SiHa.Up-regulation of GSK-3β causes the rapid degradation of Snail after transposition to cytoplasm.EMT is one of mechanisms of drug resistance and may be a novel target of treatment for drug resistance.