两种人大肠癌多药耐药株的建立及耐药性比较

目的比较递增药物质量浓度持续作用、恒定药物质量浓度周期作用两种方法建立的人大肠癌多药耐药细胞株的耐药性。方法用递增药物质量浓度持续作用、恒定药物质量浓度周期作用方式分别建立人大肠癌5-氟尿嘧啶(5-fluorouracil,5-Fu)多药耐药细胞亚系L2和L3,MTT检测两种细胞株的耐药指数,流式细胞术检测细胞周期、细胞凋亡率,实时荧光定量PCR检测多药耐药(multidrug resistance,MDR)基因mRNA表达,Western blot检测p-糖蛋白(P-glycoprotein,P-gp)的表达。结果递增药物质量浓度持续作用法诱导8个月后,细胞可以在含2.5μg/mL 5-Fu的培养液中正常生长,对5-Fu的耐药指数为26.53,对该细胞亚系命名为L2;以含2.5μg/mL 5-Fu的培养液进行筛选,6个月后细胞能稳定生长,所得细胞亚系命名为L3,其对5-Fu的耐药指数为13.78。与L2相比,G1期细胞数量较少,细胞凋亡较多,MDR1 mRNA转录水平和P-gp表达相对较低。结论大肠癌LOVO细胞株经递增药物质量浓度持续作用、恒定药物质量浓度周期作用两种诱导方式作用后,成功建立的人大肠癌5-Fu多药耐药细胞亚系L2和L3均可产生MDR;其耐药机制可能与MDR1 mRNA和P-gp的过表达有关。两种方法建立的肿瘤多药耐药模型在耐药性上有一定差异。

Establishment and comparison of two human multidrug-resistant colorectal carcinoma cell lines

Objective To compare multidrug-resistant characteristics of two human colorectal carcinoma cell lines selected/induced by continuous stepwise exposure and pulse drug exposure.Methods The human colorectal carcinoma cell line LOVO was exposed to continuous stepwise-increased concentration of 5-fluorouracil(5-Fu) and constant high concentration of 5-Fu,respectively,and the corresponding new sublines were designated as L2 and L3.Drug-sensitivity was measured by MTT.The cell cycle and apoptosis of cells were det...