肿瘤坏死因子α对人肝癌多药耐药逆转作用的实验研究

TNF-α induced reversal of multidrug resistance in human hepatocellular carcinoma cells

目的研究肿瘤坏死因子α(TNF-α)对体外培养的人肝癌耐阿霉素细胞系(HepG2/ADM)多药耐药现象的逆转作用。方法不同浓度(100、500及2500 U/ml)TNF-α作用于 HepG2/ADM 细胞72 h 后进行以下试验:用实时荧光定量聚合酶链反应技术检测各组多药耐药相关基因(MDR1)及脂质过氧化物酶体增殖物激活受体α(PPAR-α)基因的 mRNA 表达情况;用罗丹明外排法检测各组 P-糖蛋白活性;用 Annexin V 检测0.5 mg/L 阿霉素诱导的各组细胞凋亡情况;利用 MTT 法检测各组耐药性的改变。结果 TNF-α能诱导 HepG2/ADM 细胞的 MDR1基因表达下调,PPAR-α基因表达上调,且能增加阿霉素诱导的凋亡细胞的比例及细胞毒作用。结论 TNF-α可能分别通过抑制 MDR1表达及促进 PPAR-α表达而逆转 HepG2/ADM 细胞的耐药性。

Objective To investigate the reversal of multidrug resistance in the cell line HepG2/ADM induced by TNF-α. Methods HepG2/ADM cells were incubated with different concentrations of TNF- α（100,500 and 2500 U/ml） for 72 h. Real-time PCR was performed to compare the mRNA levels of MDRI with PPAR-ct in the different concentrations of TNF-α treated cells. The Armexin V assay was used to check cell apoptosis induced by 0. 5 mg/L adriamycin. Rhodamine123 efflux assay and MTT assay were used to study P-gp activity and drug resistance in each group, respectively. Results TNF-α could induce downregulation of MDR1 and up-regulation of PPAR-α. Meanwhile, it could enhance cell cytotoxicty and cell apoptosis induced by 0. 5 mg/L adriamycin. Conclusions TNF-α could partially reverse the multidrug resistance of HepG2/ADM cells by down-regulating the expression of MDR1 and up-regulating the expression of PPAR-α.