This cisplatin-resistant cell line has been developed by chronic exposure of the parent cisplatin-sensitive A2780 cell line to increasing concentrations of cisplatin. A2780cis is cross-resistant to melphalan, adriamycin and irradiation. An increased ability to repair DNA damage as well as cytogenetic abnormalities has been observed. In order to retain resistance cisplatinum has to be added to the media for every passage. In addition to this matched pair of drug-sensitive/resistant cell lines an adriamycin-resistant cell line, A2780adr, has been isolated from the same parental line A2780.