Abstract: Objective To establish drug-resistant cell line SKOV3/DDP through ovarian cancer cell line SKOV3 by induced cisplatin (DDP ),and to study its relationship with the apoptosis pathway proteins.Methods The inverted microscope was applied to observe DDP influence on the cell morphology.Methyl thiazolyl tetrazolium (MTT)assay was used to detect proliferation inhibition rate affected by DDP on SKOV3 and SKOV3/DDP cells.Flow cytometry (FCM)was used to detect the influence of cell apoptosis and the expression of X-linked inhibitor-of-apoptosis protein (XIAP ),cysteine-aspartic acid protease-3 (Caspase-3 ),B cell lymphoma/lewkmia-2(Bcl-2)and Survivin proteins.Results MTT assay showed that proliferation inhibition rate of SKOV3/DDP cells decreased significantly compared with SKOV3 cells after DDP influence (P<0.01),and depended on the concentration and time (P<0.01).The resistance index of DDP to SKOV3/DDP and SKOV3 cells in 24h,48h and 72h were respectively 2.434,2.950 and 3.780 by comparison between 50% concentration of inhibition values.FCM revealed that the apoptosis rates of SKOV3/DDP cells to DDP decreased obviously after 48h than those of SKOV3 cells (P<0.01).Compared with SKOV3 cells,the expression of XIAP,Bcl-2 and Survivin proteins in SKOV3/DDP cells were higher,while the expression of Caspase-3 protein was lower,and their differences were statistically significant (P<0.01).Conclusion Drug-resistant cell line SKOV3/DDP for ovarian cancer is successfully established and its resistance mechanism is closely related with the abnormal expression of XIAP,Caspase-3,Bcl-2 and Survivin proteins.These proteins might be involved in the drug resistance of ovarian cancer.

Key words: ovarian neoplasms, cisplatin, drug resistance, neoplasm