Relationship between microRNA-200c expression, epithelial-mesenchymal transition and the sensitivity to gefitinib in colon cancer cells / 中华消化杂志

ABSTRACT

Objective To explore the relationship between microRNA (miRNA)-200c expression,epithelial-mesenchymal transition (EMT) and the sensitivity to gefitinib in colon cancer cells.Methods The inhibitory effects of gefitinib on four types of colon cancer cell lines (HT29,SW620,HCT1116,SW480) were examined by cell counting kit-8 (CCK-8) assay.The expressions of miRNA-200c,epithelial marker (E-cadherin) and mesenchymal markers (vimentin and zinc finger Ebox binding homeobox 1 ZEB 1) at mRNA level in four types of colon cancer cell lines were detected by fluorescence quantitative polymerase chain reaction.The expressions of E-cadherin,vimentin and ZEB 1 at protein level were determined by Western blot.After up-or down-regulated the expression of miRNA-200c,the changes of the expression of EMT related genes and the sensitivity to gefitinib were observed.Results HT29 cells were most sensitive to gefitinib (IC50 =(7.70 ± 0.31) μmol/L),in which the expressions of both miRNA-200c and E-cadherin were the highest,and the expressions of vimentin and ZEB1 were extremely low.HCT116 and SW480 were moderately sensitive to gefitinib (IC50=(11.88±0.97) and (16.63±0.45) μmol/L),and the expressions of miRNA-200c and Ecadherin were moderate.SW620 cell line was most insensitive to gefitinib (IC50 =(26.43 ± 3.68)μmol/L),the expressions of miRNA-200c and E-cadherin were the lowest.The expressions of vimentin and ZEB 1 in SW620 were higher than that of the other three types of cell lines.After upregulated the expression of miRNA 200c,the expression of E-cadherin in SW620 cells increased,the expression of ZEB 1 and vimentin decreased,and the sensitivity to gefitinib increased.After downregulated the expression of miRNA-200c,the expression of E-cadherin in HT29 cells decreased,the expression of ZEB 1 and vimentin increased,and the sensitivity to gefitinib decreased.Conclusion miRNA-200c may up-regulate the expression of E-cadherin through EMT regulation,and then influence the sensitivity to gefitinib in colon cancer cells.