蛋白激酶C抑制剂逆转肾癌多药耐药机制的探讨

目的探讨蛋白激酶 C 抑制剂对肾癌细胞多药耐药性的逆转作用的机制。方法应用荧光显色法、RT- PCR、Western Blot 方法检测 PKCαcDNA 对肾癌 786- 0 细胞的转染前后细胞中 MDR 相关基因MDR1、MRP1、LRP 的表达变化。采用 MTT 法测定转染细胞系 PKC- α\786- 0 与 786- 0 细胞分别对阿霉素( ADM) 与蛋白激酶 C 激动剂、蛋白激酶 C 抑制剂协同作用后的耐药性变化。结果 RT- PCR 结果显示肾癌转染细胞 PKCα\786- 0 的 MDR1 表达水平高于肾癌 786- 0 细胞。阿霉素( ADM) 与蛋白激酶 C 抑制剂协同作用的细胞系的耐药性明显降低。786- 0 细胞对阿霉素( ADM) 的 IC50 为: 7.8015e-7(5.7046e-7 至 1.0669e-6);PKCα\786- 0 对药物阿霉素( ADM) 的 IC50 为: 1.6588e-6(1.1621e-6 至 2.3677e-6); 蛋白激酶 C 激动剂 PMA 联合阿霉素处理 PKCα\786- 0 的 IC50 为: 2.6794e-6(2.0521e-6 至 3.4983e-6); 蛋白激酶 C 抑制剂 Calphostin C 联合阿霉素处理 PKCα\786- 0 的 IC50 为: 9.2506e-8(5.9337e-8～1.4422e-7)。结论蛋白激酶 C 抑制剂可以逆转人肾癌细胞的多药耐药性, 其途经可能与改变 MDR1 的表达相关。

Mechanism of reversal of multidrug resistance in human renal cell carcinoma by inhibition agents of protein kinase C

Objective] To discuss the mechanism of inhibition agents of protein kinase C on rversal of multidrug resistance in renal cell carcinoma.Methods]Arenal cell carcinoma cell line,786-0, which stably expressed green fluorescent protein-PKC (PKC-α\786-0), was established.The sensitivity of the PKC-α\786-0 and the parental cells to adriamycin (ADM) was determined by MTT assay.The change in the sensitivity of PKC-α\786-0 and the parental cells to adriamycin (ADM) was determined by MTT assay. The change in the sensitiviyt of PKC-α\786-0 to ADM with PKC-α upregulation or downregulation was also evaluated.Results]The results of Semi-Quantitative RT-PCR Analysis showed that the expressionlevel of MDR1 was higher in RCC cellls transterred by PKCαcDNA than in RCC cells, the reversal effectiveness of inhibition agents of PKC in combination with ADM was favorable distinctly. IC50 of ADM in 786-0 cells was 7.8015e-7)5.7046e-7 to 1.0669e-6);IC50 of ADM in PKC-α\786-0 cells was 1.6588e-6(1.1621e-6 to 2.3677e-6); IC50 of ADM in combination with PMA in PKC-α\786-0 cells was 2.6794e-6(2.0521e-6 to 2.4983e-6); IC50 of ADM in combination with PMA in PKC-α\786-0 cells was 2.6794e-6(2.0521e-6 to 3.4983e-6); IC50 of ADM in combination with Calphostin C in PKC-α\786-0 cella was 9.2506e-8(5.9337e-8 to 1.4422e-7).Conclusion]Inhibition agents of PKC can reverse multidrug resistance in renal cell carcinoma by changing the expression of MDR1.