Objective The study is aimed to learn the influence of rapamycin on the sensitivity of cisplatin in ovarian cancer cell lines, and to investigate the relationship between the mTOR signaling pathway and cisplatin-resis-tance in ovarian cancer cell lines, besides, the molecular mechanism of the cytotoxic effects of rapamycin on ovarian cancer cell lines is preliminarily explored. Method The resistance index (RI) and cell proliferation inhibition rate were analyzed by CCK-8 assay. After the administration of different therapies, the influence of colony formation on the two cell lines were evaluated with clone tablet experiment. The different expression of proteins in both cell lines were detected using Western blot. Result 1) The RI of SKOV3/DDP cell line was 6.10, indicating a moderate resis-tance to cisplatin. 2) In SKOV3 cell line, the cell proliferation inhibition rate of combined therapy groups were signif-icantly higher than that of cisplatin groups after treatment for 24 h and 48 h (P<0.01), while there was no statistical difference after 72 h treatment (P>0.05). In SKOV3/DDP cell line, the cell proliferation inhibition rates of combined therapy groups were significantly higher compared to cisplatin groups in 24 h, 48 h, 72 h, with statistically significant difference (P<0.01). 3) In SKOV3 cell line, when cells were incubated with cisplatin + rapamycin for 4h, the colo-ny formation inhibition rate was significantly higher when compared with the cisplatin groups (P <0.01). 4)Gray-scale analysis showed that p-mTOR and p-AKT were overexpressed in SKOV3/DDP, while mTOR, AKT had similar ex-pression. 5) Rapamycin + cisplatin had more cleavage than cisplatin groups. 6) SKOV3 cell line had a decreased ex-pression of BCL2, and an increased transformation from LC3BI to LC3BII when treated with rapamycin for 24 hours; And those were not observed in SKOV3/DDP cell line. Conclusion 1) In vitro, rapamycin can enhance the chemosensitivity of SKOV3 and SKOV3/DDP cell lines to cisplatin. 2) The activation of the mTOR pathway may play an important role in the development of cisplatin-resistance. 3) Rapamycin increases the chemosensitivity of SKOV3 cell line to cisplatin, of which the underlying molecular mechanisms may include: enhancement of cisplatin-induced DNA cleavage, downregulation of BCL2 and induce of autophagy, while the mechanisms involved in SKOV3/DDP cell line only include the enhancement of cisplatin-induced DNA cleavage.%目的：研究雷帕霉素对卵巢癌细胞系顺铂敏感性的影响，以及PI3K/AKT/mTOR信号通路（简称mTOR信号通路）与卵巢癌细胞系顺铂耐药的相关性；初探雷帕霉素增强卵巢癌细胞系顺铂敏感性的分子机制。方法采用CCK-8法检测卵巢癌顺铂耐药细胞系SKOV3/DDP的耐药指数（resistance index，RI）、细胞增殖抑制率；采用克隆平板实验观察不同用药方案对卵巢癌顺铂非耐药细胞系及SKOV3细胞系两种细胞系克隆形成的影响；采用蛋白质印迹法（Western blot）检测两种细胞系的蛋白表达差异。结果①SKOV3/DDP细胞系的RI为6.10，属中度耐药。②在SKOV3细胞系中，顺铂联合雷帕霉素作用24 h、48 h后的细胞增殖抑制率明显高于单用顺铂组，差异有统计学意义（P＜0.01），两组间的72 h细胞增殖抑制率无明显的统计学意义（P＞0.05）；顺铂联合雷帕霉素作用于SKOV3/DDP细胞系24 h、48 h、72 h后的细胞增殖抑制率均明显高于单用顺铂组，差异有统计学意义（P＜0.01）。③雷帕霉素联合顺铂作用于SKOV3细胞系4 h后，其克隆形成抑制率明显高于单用顺铂组，差异有统计学意义（P＜0.01）。④SKOV3/DDP细胞系比SKOV3细胞系p-mTOR、p-AKT的表达升高，而mTOR、AKT的表达则相似。⑤联合用药组比单用顺铂组的PARP断裂增加。⑥雷帕霉素作用SKOV3细胞系24 h ，BCL2表达下调，LC3B由LC3BⅠ向LC3BⅡ转化增加；在SKOV3/DDP细胞系中未发现这两种作用。结论①在体外培养条件下，雷帕霉素能增强SKOV3及SKOV3/DDP细胞系对顺铂的敏感性。②mTOR信号通路激活可能在卵巢癌细胞系顺铂耐药机制中起重要作用。③雷帕霉素增强SKOV3细胞系对顺铂敏感性的分子机制包括：增强顺铂所致的DNA断裂、下调抗凋亡蛋白BCL2及引起细胞自噬；雷帕霉素增强SKOV3/DDP对顺铂敏感性分子机制可能与增强顺铂所致的DNA断裂有关。
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