沉默FASN基因对肝母细胞瘤HepG2细胞的脂质代谢及增殖、迁移和凋亡的影响

目的 研究FASN基因沉默对肝母细胞瘤HepG2细胞脂质代谢及生物学行为的影响。方法 以脂质体包裹siRNA的方法沉默FASN基因，实验分为Control组、NC-siRNA组和FASN-siRNA组，FASN-siRNA组转染75 nmol/L的FASN-siRNA片段，NC-siRNA组转染等剂量的NC-siRNA片段，Control组只加入等体积的转染试剂。通过实时荧光定量PCR和Western blot法检测FASN基因和蛋白水平的相对表达；通过酶联免疫吸附法检测HepG2细胞甘油三酯水平；通过油红O染色法检测细胞内脂滴数目；利用CCK-8实验检测HepG2细胞增殖活性的改变；通过annexinV-FITC/PI双染色法检测HepG2细胞凋亡情况；采用划痕愈合实验及transwell实验检测HepG2细胞迁移能力的改变。结果 FASN-siRNA组的FASN基因表达、蛋白表达低于NC-siRNA组（P<0.001）。油红O染色显示，FASN-siRNA组细胞内脂滴较NC-siRNA组减少（P<0.001）、甘油三酯水平降低（P< 0.01）；CCK-8实验、annexinV-FITC/PI双染实验及划痕愈合实验结果显示，转染48、72、96 h后，FASN-siRNA组HepG2细胞增殖被显著抑制，FASN-siRNA组细胞总凋亡率与NC-siRNA组相比增加、FASN-siRNA组发生迁移的HepG2细胞数量低于NC-siRNA组（P<0.001）。结论 沉默FASN基因可抑制肝母细胞瘤HepG2细胞的增殖及迁移，并诱导HepG2细胞凋亡，该作用可能与FASN基因抑制后HepG2细胞内脂质合成降低有关。

Effect of fatty acid synthase gene silencing on lipid metabolism and biological behaviors of human hepatoblastoma HepG2 cells

Objective To investigate the effect of fatty acid synthase (FASN) gene silencing on lipid metabolism and biological behaviors of human hepatoblastoma HepG2 cells. Methods Small interfering RNA (siRNA) targeting FASN gene or a negative control siRNA sequence (NC-siRNA) was transfected into HepG2 cells, and the gene silencing efficiency was evaluated with qRT-PCR and Western blotting. Triglyceride level in the cells was detected using enzyme-linked immunosorbent assay, and Oil red O staining was performed to examine intracellular lipid droplets. The proliferation ability of the transfected cells was tested by CCK-8 assay, and cell apoptosis was evaluated using annexin V-FITC/PI apoptosis detection kit. Wound healing assay and Transwell assay were performed to assess the migration ability of the transfected cells. Results Transfection of the cells with FASN-siRNA, but not NC-siRNA, significantly lowered FASN expression at both the mRNA and protein level (P< 0.001) and decreased the number of lipid droplets (P<0.001) and triglyceride level (P<0.01) in the cells. FASN gene silencing significantly inhibited proliferation, increased apoptosis rate and suppressed migration of HepG2 cells (P<0.001). Conclusion FASN gene silencing inhibits proliferation and migration and promotes apoptosis of HepG2 cells possibly by suppressing lipid synthesis in the cells.