Induction of p53 and drug resistance following treatment with cisplatin or paclitaxel in ovarian cancer cell lines

Treatment failures result from resistance to chemotherapy in ovarian cancer. The effect of cisplatin and paclitaxel treatments on chemosensitivity was studied in ovarian cancer cells developed from a patient with stage IIIC disease. Cells (UL-3A, UL-3B) that recovered from cisplatin (Cis) and paclitaxel (Tax) treatments showed higher levels of p53, mdr-1 and chemoresistance than untreated controls. EC50 values of Cis and Tax for UL-3A clones were 7.2-34.6, average 20.9 microg/ml, while UL-3B clones ranged from 11.8-252.0 microg/ml, with a mean value of 73.2 microg/ml for Cis, and 260.0-4400.0 nM (mean 2555.0 nM) for Tax. Selection pressures during treatment may contribute to drug resistance.