Modulation of cisplatin cytotoxicity by human recombinant interferon-gamma in human ovarian cancer cell lines

Cytotoxic interactions between recombinant human interferon-gamma (IFN gamma) and cisplatin have been studied in six ovarian cell lines (IGROV1, NIHOVCAR3, SKOV3, OVCCR1, 2008 and its cisplatin resident variant 2008/C13*). Studies were performed using a cell survival assay. Results were assessed using median effect analysis. Synergy between these two drugs was observed in cell lines sensitive to IFN gamma, whatever their relative sensitivity or resistance to cisplatin, suggesting that IFN gamma enhances the cytotoxic activity of cisplatin. This interaction is not due to an increase in platinum accumulation in cells. This combination of drugs should be evaluated against human ovarian cancer xenografts in nude mice before its use in clinical practice.