三氧化二砷联合BSO对K562／ADM细胞P-糖蛋白的抑制作用研究

目的研究三氧化二砷（As2O3）联合γ-谷氨酰半胱氨酸合成酶抑制剂丁硫氨酸亚砜胺（BSO）对肿瘤多药耐药细胞K562／ADM细胞中P-糖蛋白（P—gP）的抑制作用，比较单用As2O3与两药联合的作用效果。方法As2O3组（0．5μmol／L，2．0μmol／L，5．0μmol／L）单独及联合100μmol／LBSO作用于K562／ADM细胞后，分光光度法检测K562／ADM细胞内谷胱甘肽（GSH）含量变化；流式细胞术（FCM）检测P-gp蛋白水平表达变化；反转录一聚合酶链反应（RT—PCR）方法检测mdr-1 mRNA的表达变化。结果As2O3临床剂量组（0．5μmol／L，2μmol／L）联合BSO24h内即可抑制P-gp和mdr-1mRNA的表达水平，在48h后，临床剂量联合组抑制mdr-1mRNA的作用效果要明显强于单用高剂量组，在72h后，临床剂量联合组抑制P—gP的作用效果要明显强于单用高剂量组。结论临床剂量As2O3联合BSO可有效抑制K562／ADM细胞P—gp及mdr-1 mRNA的表达。

In vitro study of the effect of arsenic trioxide combined with BSO on inhibiting P-glycoprotein expression in K562/ADM cell

Objective To investigate the effect of arsenic trioxide (As2O3) and buthionine sulfoximine (BSO) on inhibiting P-glycoprotein expression in multidrug-resistant cell-K562/ADM cell. To compare the effect of As2O3 and the combined group .To determine the effect of intracellular glutathione content on the arsenic effect. Methods To investigate the effect of the arsenic group (0.5 μmol/L, 2.0 μmol/L, 5.0 (μmol/L) and/or BSO (100 μmol/L) on K562/ADM cell. Intracellular GSH contents were measured using glutathione assay kit by spectrophotometry.P-gp expression were determined by flow cytometry. Mdr-1mRNA expression were directed by semi-quantitative RT-PCR. Results P-gp expression and mdr-1mRNA expression were inhibited in 24 hours in the combination of clinic dose arsenic group (0.5 (μmol/L, 2 μmol/L)and 880(100 μmol/L). In 48 hours, the mdr-1mRNA depressive effect of the combination group (clinic dose arsenic group) was obviously stronger than high dose arsenic group. In 72 hours, the P-gp depressive effect of the combination group (clinic dose arsenic group) was obviously stronger than high dose arsenic group.Conclusion The combination of clinic dose arsenic and BSO inhibit obviously P-gp expression and mdr-1mRNA expression in K562/ADM cell.