人结肠癌耐药细胞系SW480/L-OHP的建立及其耐药机制初探

Establishment of Human Colon Carcinoma SW480 Cell Line Resistant to L-OHP and Preliminary Exploration into the Mechanism of Resistance

目的构建对奥沙利铂(L-OHP)耐药的人结肠癌细胞系SW480/L-OHP,并初步探索其耐药特性。方法以逐渐递增L-OHP浓度方法构建人结肠癌耐药细胞系模型SW480/L-OHP,观察其生长规律和绘制生长曲线;MTT法检测其耐药性和计算耐药指数;流式细胞仪检测其细胞周期和罗丹明123蓄积量。结果成功构建稳定耐药的SW480/L-OHP,耐药指数为(6.23±2.33),且对其他抗肿瘤药也有一定程度的交叉耐药。体外细胞群体倍增时间延长;细胞内罗丹明累计实验测定其含量明显减少,细胞周期显示其出现G2/M期阻滞。结论 SW480/L-OHP细胞株耐药性较稳定,具备耐药细胞的基本生物学特征,其耐药机制可能与细胞周期改变和P-gp功能增强有关。

ABSTRACT. Objective To establish oxaliplatin （L-OHP）-resistant human colon carcinoma cell line （SW480/L-OHP） and to preliminarily study its resistant characteristics. Methods Resistance to L-OHP was induced by continuously exposing the human colon carcinoma SW480 cells to gradually increasing con- centrations of L-OHP. The rate of cell growth was measured and the growth curve plotted. The extent of resistance to L-OHP was determined by MTT assay and the resistant index calculated. Cell cycle phase distribution and intracellular Rhodamine 123 accumulation were assessed by flow cytometry. Results The SW480/L-OHP cells with stable resistance were successfully established with the resistance index of （6.23-t-2. 33）. SW480/L-OHP cells were cross-resistant to other chemotherapeutic drugs to some extent. In vitro doubling time of the cell population was increased. Intracellular accumulation of rhodamine was significantly reduced. Cell cycle arrested at G2/M phase. Conclusions SW480/L-OHP cell line demonstrates relatively stable resistant phenotypes with essential characteristics of multi-drug re- sistance. The underlying mechanisms may be related to the disturbance of cell cycle progression and the increase of P-glycoprotein function.