雷帕霉素逆转卵巢癌细胞系SKOV3/DDP顺铂耐药及其机制探讨

Resistance Reversion of Rapamycin on Ovarian Cancer Cell Line SKOV3/DDP and Its Molecular Mechanisms

【目的】研究雷帕霉素对卵巢癌顺铂耐药细胞系SKOV3/DDP的逆转作用并探讨其相关分子机制。【方法】采用四甲基偶氮唑蓝(MTT)法测定卵巢癌顺铂耐药细胞系SKOV3/DDP的耐药倍数、雷帕霉素对其细胞毒性及逆转倍数;Western blot法检测雷帕霉素对细胞内Akt/m TOR相关通路蛋白表达的影响。【结果】(1)MTT法检测出雷帕霉素浓度分别为25、50、100、500和1 000μg/L对卵巢癌顺铂耐药细胞系SKOV3/DDP的抑制率分别为4.48%、25.30%、35.86%、67.82%和81.43%。选择抑制率小于5%的最大雷帕霉素浓度即25μg/L作为逆转浓度;(2)卵巢癌顺铂耐药细胞株SKOV3/DDP耐药指数RI为2.21;(3)25μg/L雷帕霉素对卵巢癌顺铂耐药细胞系SKOV3/DDP逆转倍数为1.63;(4)Western blot结果:加用雷帕霉素后,卵巢癌细胞SKOV3和卵巢癌顺铂耐药细胞SKOV3/DDP的p-mTOR及其下游的p-p70s6k表达均明显降低。同时,雷帕霉素作用于SKOV3及SKOV3/DDP细胞后,均出现p-Akt反馈性增高。【结论】雷帕霉素对卵巢癌顺铂耐药细胞系SKOV3/DDP具有耐药逆转作用,其机制可能为通过抑制Akt/mTOR通路中mTOR及下游相关蛋白表达进而抑制耐药细胞的增殖并促进其凋亡进程。

【Objective】To study the resistance reversion of rapamycin on ovarian cancer cell line SKOV3/DDP,and ex-plore its underlying molecular mechanisms.【Methods】MTT method was used to detect the cell toxicity,drug-resistant multi-ple and reversing multiple of cisplatin-resistant ovarian cancer cell line SKOV3/DDP;Western blot was used to detect thechanges of Akt/mTOR Pathway induced by rapamycin.【Results】(1) MTT detected that when rapamycin concentration was25,50,100,500 and 1 000 μg/L,its inhibition rates on cisplatin-resistant ovarian cancer cell line SKOV3/DDP were4.48%,25.30%,35.86%,67.82%,81.43%. The concentration of 25 μg/L was selected to be the reversal concentration,be-cause its maximum rate was less than 5%.(2) The resistant index(RI)of cisplatin-resistant ovarian cancer cell line SKOV3/DDP was 2.21.(3) The reversal fold of 25 μg/L rapamycin on cisplatin-resistant ovarian cancer cell line SKOV3/DDP was 1.63.(4) Western blot results:After the addition of rapamycin,expression of p-mTOR and its downstream protein p-p70s6 kin SKOV3 and SKOV3/DDP was significantly reduced. Meanwhile,there was a feedback increase in p-Akt.【Conclusions】Rapamycin has a reversal effect on cisplatin-resistant ovarian cancer cell line SKOV3/DDP. Its reversal mechanism may beinhibiting the cell proliferation and promoting cell apoptosis by depressing the expression of p-mTOR and its downstream pro-tein p-p70s6k in Akt/m TOR Pathway.