PTEN and PDCD4 are bona fide targets of microRNA-21 in human cholangiocarcinoma.
- Author:
Chang-zheng LIU
1
;
Wei LIU
;
Yi ZHENG
;
Jin-mei SU
;
Jing-jing LI
;
Lan YU
;
Xiao-dong HE
;
Song-sen CHEN
Author Information
- Publication Type:Journal Article
- MeSH: Apoptosis Regulatory Proteins; genetics; Bile Duct Neoplasms; genetics; pathology; Bile Ducts, Intrahepatic; metabolism; pathology; Cell Line, Tumor; Cholangiocarcinoma; genetics; pathology; Female; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; drug effects; Humans; Male; MicroRNAs; genetics; physiology; Middle Aged; PTEN Phosphohydrolase; genetics; RNA-Binding Proteins; genetics; Transfection
- From: Chinese Medical Sciences Journal 2012;27(2):65-72
- CountryChina
- Language:English
-
Abstract:
OBJECTIVETo investigate the expression profile of microRNA-21 in human cholangiocarcinoma tissues and to validate its bona fide targets in human cholangiocarcinoma cells.
METHODSThe expression profile of microRNA-21 in human cholangiocarcinoma tissues and cholangiocarcinoma cell line, QBC939, was evaluated by using real-time PCR analysis. The bona fide targets of microRNA-21 were analyzed and confirmed by dual luciferase reporter gene assay and western blot, respectively. The expressional correlation of microRNA-21 and its targets was probed in human cholangiocarcinoma tissues by using real-time PCR, locked nucleic acid in situ hybridization (LNA-ISH), and immunohistochemistry analysis.
RESULTSReal-time PCR analysis revealed that microRNA-21 expression depicted a significant up-regulation in human cholangiocarcinoma tissues about 5.6-fold as compared to the matched normal bile duct tissues (P<0.05). The dual luciferase reporter gene assay revealed endogenous microRNA-21 in cholangiocarcinoma cell line, QBC939, inhibited the luciferase reporter activities of wild-type PTEN (P<0.01) and PDCD4 (P<0.05) and had no this effect on mutated PTEN and PDCD4. Moreover, loss of microRNA-21 function led to a significant increase of PTEN and PDCD4 protein levels in QBC939 cells. Elevated microRNA-21 levels were accompanied by marked reductions of PTEN and PDCD4 expression in the same cholangiocarcinoma tissue.
CONCLUSIONmicroRNA-21 expression is up-regulated in human cholangiocarcinoma and PTEN, PDCD4 are direct effectors of microRNA-21.