miR-143通过靶向FASN抑制肝癌HepG2细胞脂质形成

Inhibition of the lipogenesis of hepatocellular carcinoma HepG2 cells by miR-143 via suppressing FASN

目的研究miR-143对肝癌Hep G2细胞脂质形成的影响及其分子机制。方法应用qRT-PCR方法检测miR-143在临床肝癌和癌旁组织以及肝癌细胞系和正常肝细胞系中的表达。通过油红O染色实验检测miR-143对肝癌细胞脂质形成的影响。Western blotting检测miR-143对肝癌细胞中脂肪酸合成酶(FASN)表达的影响。通过报告基因实验检测miR-143及其抑制子对报告基因载体FASN-CDS活性的影响。结果 qRTPCR结果表明在临床肝癌组织和Hep G2细胞中miR-143的表达显著低于癌旁组织和Chang liver肝细胞系(P<0.01)。油红O染色实验结果显示,miR-143能显著降低肝癌细胞中脂质的形成。qRT-PCR和Western blotting结果证实,miR-143可以显著下降FASN的mRNA和蛋白表达水平。报告基因检测结果表明,在Hep G2细胞中miR-143可以显著降低FASN-CDS报告基因的活性(P<0.01);相反,miR-143抑制子可以显著升高FASN-CDS的活性(P<0.01)。在Hep G2细胞中miR-143抑制子可以上调FASN的表达并促进脂质形成。结论 miR-143可以通过抑制FASN的表达阻碍肝癌细胞脂质形成。

Objective To investigate the effects of miR-143 on the lipogenesis of hepatocellular carcinoma Hep G2 cells and the molecular mechanism. Methods Expressions of miR-143 of the clinical hepatocarcinoma tissue,para cancer tissue, hepatocellular carcinoma cell line, and normal liver cell line were detected by quantitative realtime polymerase chain reaction（ qRT-PCR）. The effect of miR-143 on the lipogenesis of hepatocellular carcinoma cells was detected by the oil red O staining assay. The effect of miR-143 on the expression of fatty acid synthase（ FASN） of hepatocellular carcinoma cells was detected by the Western blotting. The effects of miR-143 and its inhibitor on the activity of reporter gene vector FASN-CDS were detected by the reporter gene assays. Results The results of qRT-PCR showed that the expression of miR-143 of the clinical hepatocarcinoma tissue and Hep G2 cells significantly lower than that of the para cancer tissue and Chang liver cell line（ P〈0. 01）. The results of oil red O staining assay indicated that miR-143 significantly decreased the lipid formation of hepatocellular carcinoma cells.The results of qRT-PCR and Western blotting showed that miR-143 significantly decreased mRNA and protein levels of FASN. The results of reporter gene assays indicated that miR-143 in Hep G2 cells significantly decreased the activity of FASN-CDS（ P〈0. 01）, while the inhibitor of miR-143 significantly increased the activity of FASN-CDS（ P〈0. 01）. The inhibitor of miR-143 in Hep G2 cells was able to up-regulate the expression of FASN and enhance the lipogenesis. Conclusion MiR-143 can inhibit the lipogenesis of hepatocellular carcinoma cells by suppressing the expression of FASN.