大肠癌耐药LoVo/Adr细胞PKC亚型与MDR的关系

Relationship between protein kinase C isoforms and MDR in colorectal cancer multidrug resistant LoVo/Adr cells

目的 :探讨大肠癌LoVo/Adr细胞蛋白激酶 (PKC)亚型分布与多药耐药 (MDR)关系 .方法 :采用Westernblot法 ,检测PKCα ,PKCβ和PKCγ和PKCε在LoVo/Adr细胞胞膜和胞质中的表达 ;采用流式细胞术 ,检测了PKC对LoVo/Adr细胞阿霉素摄入的影响 .结果 :在LoVo/Adr细胞中 ,PKCα主要分布在胞膜中 ,且含量显著高于LoVo细胞 ;PMA作用 30min时 ,可以使胞质中的PKCα几乎全部转移到胞膜中 ,PMA作用 2 4h时 ,胞质和胞膜中PKCα几乎测不到 ;PMA作用 30min时 ,阿霉素摄入量 (荧光强度 )由原来的 2 .0 4± 0 .70减少到 1 .74± 0 .5 6 ,显著减少 (P <0 .0 1 ) ;PMA作用 2 4h时 ,阿霉素摄入量增加到 2 .2 1± 1 .2 8,显著增加 (P <0 .0 1 ) .结论

AIM: To investigate the relationship between PKC isoforms and MDR in colorectal cancer multidrug resistant LoVo/Adr cells. METHODS: Western blot was used for assessment of PKCα, PKCβ, PKC γ and PKCε expression on membrane and in cytoplasma of LoVo/Adr cells. The effect of PKC on uptake of adriamycin in LoVo/Adr cells was determined by flow cytometry. RESULTS: PKCα was mainly distributed on membrane of LoVo/Adr cells and its amount was significantly higher in LoVo/Adr cells than in LoVo ones. PKCα was transformed to membrane from cytoplasma after 30 min treatment with PMA and PKCα expression was hardly determined on membrane and in cytoplasma after 24 h treatment with PMA. The uptake of adriamycin decreased significantly from (2.04±0.70) to (1.74±0.56) after 30 min treatment with PMA ( P <0.01), but increased significantly to (2.21±1.28) ( P <0.01) after 24 h treatment with PMA. CONCLUSION: PKCα might be involved in MDR.