大肠癌多药耐药细胞蛋白激酶C的表达及作用

目的:检测电离辐射作用后大肠癌多药耐药细胞蛋白激酶C(PKC)的表达和观察蛋白激酶C在多药耐药发生发展中的作用。方法：对大肠癌HCG-8多药耐药细胞照射,照射后用间接免疫荧光技术,采用流式细胞仪检测X射线对HCG-8细胞PKC表达的影响。结果：与假照组相比,2 Gy大剂量照射后PKC阳性细胞百分率明显增加(P<0.05),先给予低剂量照射(50和100 mGy),再给予大剂量照射,PKC阳性细胞百分率增加不明显,200 mGy+2 Gy组PKC阳性细胞百分率明显增加(P<0.05)。与单纯2 Gy大剂量照射组比较,100 mGy+2 Gy组PKC阳性细胞百分率明显降低(P<0.05)。结论：大剂量辐射可使大肠癌细胞PKC蛋白表达明显增加,而预先给予低剂量辐射后再给予大剂量辐射可使大剂量辐射增强PKC蛋白表达作用不明显。

Expression of protein kinase C in multidrug resistant cells of colorectal carcinoma

Objective To detect the expression of protein kinase C(PKC) in multidrug resistant cells of colorectal carcinoma after ionizing irradiation and observe the effect of PKC on occurrence and development of the multidrug resistant.Methods The effect of PKC on multidrug resistant HCG-8 cells of colorectal carcinoma after treated with X-ray was detected by indirect immunofluorescence technique and flow cytometry.Results Compared with sham-irradiation group,the positive percentage of PKC was increased significantly(P<0.05) after HCT-8 cells were treated with 2 Gy X-ray,the positive percentages of PKC were increased insignificantly after HCT-8 cells were treated with low dose(50,100 mGy) before high dose of irradiation,the increasing of positive percentage of PKC in the group of 200 mGy 2 Gy was significant(P<0.05).Compared with the group only treated with high dose of irradiation,the positive percentage of PKC in the group of 100 mGy 2 Gy was decreased significantly(P<0.05).Conclusion High dose of ionizing irradiation can increase the expression of PKC in colorectal carcinoma significantly,reversely when HCT-8 cells are pretreated with low dose before high dose there is no additional increase of PKC expression.