Identification of up-regulated miRNAs in extrahepatic and intrahepatic cholangiocarcinoma

Abstract

Objective To investigate the expression profile of miRNAs up-regualted in human extrahepatic and intrahepatic cholangiocarcinoma tissues and probe the effect on cell growth of four of these miRNAs in QBC939 cell line.Methods Up-regulated miRNAs in extrahepatic or intrahepatic cholangiocarcinoma tissues were analyzed by using miRNA-microarray,which was confirmed by using miRNA Real-Time PCR analysis.Based on these findings,four of these up-regulated miNRAs were chosen to perform function investigation.The specific miRNA inhibitors were transfected into QBC939 cells,respectively,and cell proliferation assay was performed by using MTT.Results 12 miRNAs were up-regulated both in two types of cholangiocarcinoma tissues,28 miRNAs and 21 miRNAs were up-regulated in extrahepatic cholangiocarcinoma and intrahepatic cholangiocarcinoma,respectively.MiR-125b and miR-19a expression levels were increased about 3.7 and 3.6 fold,compared with the matched normal bile duct tissues (P＜0.05).MiR-92a and miR-205 expression was upregulated about 4.S- and 3.5-fold,compared with the matched normal bile duct tissues (P＜0.05).MiR-125b,miR19a,miR-21,and miR 378* were inhibited in QBC939 cells,which indicated a significant inhibitory effect on cell growth.The ratio of inhibition was 71％,72％,69％,and 76％(P＜0.05)at 36 h,61％,63％,60％,and 59％(P＜0.01) at 48 h,and 61％、56％、60％ and 59％(P＜0.05) at 60 h.Conclusion The miRNAs expression patterns in human extrahepatic and intrahepatic cholangiocarcinoma tissues are different and uo-regulated miRNAs act as oncomirs on cholangiocarcinoma cell growth. Key words: Extrahepatic cholangiocarcinoma; Intrahepatic cholangiocarcinorna; MicroRNAs; Cell growth