【摘要】 目的探讨低浓度活性氧对肾癌786-O细胞先天性多药耐药的逆转作用及相关机制。方法采用WST-1细胞增殖及细胞毒性检测试剂盒确定活性氧H2O2的非细胞毒性剂量,以及对786-O细胞药物敏感性的影响。罗丹明123实验检测细胞P糖蛋白(P-gp)功能,Western blot方法检测经典多药耐药基因(mdr1)产物P-gp的表达。结果在0.00001～0.1mmol/L浓度范围内,H2O2具有明显的促细胞生长作用,且显著增加了阿霉素及长春新碱的细胞毒性,0.02mmol/LH2O2孵育786-O细胞72h后其对阿霉素及长春新碱的药物敏感性分别增加至对照组的5.43及4.47倍,荧光染料罗丹明123的蓄积量显著增加,Western blot检测结果显示0.02mmol/LH2O2可抑制肾癌786-O细胞P-gp的表达。结论低浓度活性氧H2O2可部分逆转人肾癌786-O细胞先天性多药耐药对阿霉素的耐药性,其逆转机制与增加细胞内化疗药物浓度、抑制P-gp的表达有关。更多还原

【Abstract】 Objective To investigate the reversal effect of lower concentration reactive oxygen species (ROS) on human renal cell carcinoma (RCC) cell line 786-O, a intrinsic-resistance cell line of human RCC, and its possible mechanisms. Methods Cytotoxicity of ROS and its sensibility to adriamycin (ADM) or vincristine (VCR) in 786-O cell line were assessed by the WST-1 (tetrazolium salts) colorimetric assay using a Cell Counting Kit. The P-gp mediated efflux in RCC cells was determined by measuring the retention of a fluorescent P-gp substrate, rhodamine 123 dye. P-gp production determined by Western blot. Results Lower concentrations of H2O2 (about 0.000 01-0.1 mmol/L) can enhanced cell growth and sensitized RCC cells to ADM and VCR, which dramatic increased the toxicity of ADM and VCR compared with single chemotherapeutic drugs treatments. After incubation with 0.02 mmol/L H2O2 for 72 h, the sensitivity of 786-O to ADM or VCR was enhanced by 5.43, 4.47 times, respectively (P<0.01 vs control or drug alone). The residual ratio of rhodamine 123 in 786-O cells was significantly increased. The expressions of P-gp in RCC cell line 786-O incubate with lower concentration H2O2 were decreased when detected by Western blot. Conclusions Lower concentration ROS could partially reverse the multidrug resistance of RCC cell line 786-O in vitro.Furthermore, the reversal effect may be due to the increase of intracellular accumulation of chemotherapeutic drugs and the decrease of the expressions of and P-gp.更多还原