Silencing PPARγ gene inhibits proliferation and inducs apoptosis of hepatoma HCCLM3 cells / 肿瘤

ABSTRACT

Objective: To observe the effects of knocking down the expression of peroxisome proliferators-activated receptor gamma (PPARγ) with RNA interference techniques on the proliferation and apoptosis of hepatocellular carcinoma HCCLM3 cells. Methods: A short-hairpin RNA (shRNA) eukaryotic expression vector against PPARγ was constructed and transfected into HCCLM3 cells. The changes of PPARγ expression were detected by semi-quantitative RT-PCR and Western blotting analysis. The proliferation of HCCLM3 cells was tested by MTT assay. Apoptosis ratio of HCCLM3 cells was detected by TUNEL method and flow cytometry (FCM). Expressions of PCNA and wide-type p53 protein were analyzed by immunocytochemistry (ICC) methods. Results: The sequence-specific shRNA (pshPPARγ) efficiently blocked the expression of PPARγ mRNA by 80.5%. At 48 h after transfection of pshPPARγ, proliferation of HCCLM3 cells was significantly suppressed by 71.5%. The positive rate of PCNA expression was (23.8 ± 7.2)% at 40 h transfection. The apoptotic rates were (24.2 ± 4.7)% as detected by TUNEL assay and (23.2 ± 4.2)% of cells as measured by FCM test, respectively. The detection results of the two methods were consistent. In pshPPARγ transfection group, cell cycle of HCCLM3 cells was arrested in G0/G1 phase and the proportion of cells in G2/M phase decreased. Moreover, expression of wide-type p53 protein increased significantly. Conclusion: Knockdown PPARγ expression with RNA interference technology can significantly suppress proliferation and induce apoptosis of HCCLM3 cells. It is related with up-regulation of wide-type p53 protein expression.