miR-20a induces cell radioresistance by targeting PTEN in hepatocellular carcinoma
Zhang Yuqin, Chen Longhua, Ding Yi, Zheng Lin
Department of Radiation Oncology,the First Affiliated Hospital of Jinan University,Guangzhou 510613,China (Zhang YQ);Department of Radiation Oncology,Nanfang Hospital,Southern Medical University,Guangzhou 510515,China (Chen LH,Ding Y);Department of Pathology,School of Basic Medical Sciences,Southern Medical University,Guangzhou 510515,China (Zheng L)
Objective To explore the role and mechanism of miR-20a in the radiosensitivity of hepatocellular carcinoma (HCC). Methods The expression level of miR-20a in HCC cell lines and tissue specimens was detected by real-time fluorescent quantitative PCR.HCC cell line stably over-expressing miR-20a was constructed. The effect of miR-20a on HCC cell radiosensitivity was evaluate by cloning assay. The expression levels of Bcl-2,Caspase-3 and γ-H2AX proteins were quantitatively detected by Western blot. The target gene of the downstream regulation of miR-20a was predicted by bioinformatics analysis,which was further verified by dual luciferase reporter assay,real-time fluorescent quantitative PCR and Western blot. HCC cell line stably overexpressing miR-20a was transfected with pCDNA3.0-PTEN to investigate the changes in the radiosensitivity of cells and to determine whether PTEN is a functional target gene for miR-20a-induced radioresistance of HCC. Results The expression levels of miR-20a was significantly up-regulated in HCC cell line and tissue specimens (both P<0.05).After identical radiotherapy,the cell survival rate,the radioresistance was strengthened (P<0.05),the expression of Bcl-2 was up-regulated,whereas the expression levels of Caspase-3 and γ-H2AX were down-regulated in the LV-miR-20a group compared with those in the blank and control groups (WT and LV-con groups).Overexpression of PTEN could reverse the miR-20a-induced radioresistance. Conclusion miR-20a is up-regulated in the HCC cell lines and tissue specimens. Overexpression of miR-20a can promote the radioresistance of HCC cells. PTEN is a functional target gene for miR-20a-induced radioresistance of HCC,indicating that miR-20a/PTEN site may be an effective molecular target associated with clinical radiotherapy for liver cancer.
Zhang Yuqin,Chen Longhua,Ding Yi et al. miR-20a induces cell radioresistance by targeting PTEN in hepatocellular carcinoma[J]. Chinese Journal of Radiation Oncology, 2018, 27(9): 850-854.
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