目的 采用浓度梯度法诱导建立人膀胱癌顺铂耐药细胞系（T24/DDP）,并观察其生物学特性。方法 利用人膀胱癌细胞株T24，采用顺铂（DDP）作为诱导剂在体外建立人膀胱癌顺铂耐药细胞模型T24/DDP(0.6μg/mL)。通过倒置相差显微镜下观察T24、T24/DDP细胞形态，MTT法检测细胞多药耐药性，生长曲线检测细胞的增殖能力，流式细胞术测细胞的周期,qRT-PCR检测耐药基因MRP（multidrug resistance-associated protein）的表达。结果 经过顺铂14个月的诱导，成功建立了T24/DDP。倒置相差显微镜下观察与T24细胞相比较，T24/DDP排列不规则，形态出现多形性，出现巨细胞； 与T24相比较，T24/DDP对顺铂、阿霉素、长春新碱、甲氨蝶呤均产生不同程度的交叉耐药，比T24细胞倍增时间明显延长，细胞周期中G1期细胞增多，G2、S期细胞减少。qRT-PCR结果显示，耐药细胞MRP基因的表达明显高于亲本细胞。结论 人膀胱癌耐顺铂细胞株T24/DDP具有多药耐药性，可以作为研究膀胱癌细胞多药耐药的良好实验模型。

Abstract: Objective To establish a cisplatin resistant bladder cancer cell line and to analysis its biological characteristics．Method Drug concentration gradient increasing method was adopted to induce drug resistance. T24 and T24/DDP were observed under phase contrast microscope. Multidrug resistance of the two cell lines was determined by MTT. Cell proliferation was evaluated according to the growth curve. Flow cytometry was performed to determine cycles of the two cell lines. The expression of multidrug resistance related gene multidrug resistance-associated protein (MRP) was detected by qRT-PCR. Results After 14 months, cisplatin-resistant human bladder cancer cell line T24/DDP was successfully established from its parental cell line T24. Two kinds of cells were significantly different from each other by a microscope. T24/DDP cell was 9.51 times more resistant to DDP than T24. T24/DDP cell line exhibited the characteristics of cross-resistance to cisplatin, adriamycin, methotrexate, vincristine. The cell doubling time of T24/DDP was longer than parental cell line T24. Compared with T24， the proportion of G2 and S phase cells in T24/DDP decreased significantly，while that of G1 phase cells increased significantly．The expression of drug-resistance related gene MRP was significantly up-regulated in T24/DDP（P＜0．05）．Conclusion With the characteristics of multidrug resistance, cisplatin-resistant human bladder cancer cell line T24/DDP could be used as a good experimental model for further study on bladder cancer multidrug resistance.