Gynecologic oncology
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Gynecologic oncology · Jul 2004
The role of topotecan for extending the platinum-free interval in recurrent ovarian cancer: an in vitro model.
Topotecan, a novel topoisomerase-I inhibitor, is an active agent of second-line chemotherapy for extending the platinum-free interval (PFI) and improving the chances of a response to platinum in recurrent ovarian cancer patients. The aim of this study was to understand the molecular mechanism of topotecan-based second-line chemotherapy through an in vitro cell culture model and to gain clinical insight into sequencing issues for second-line treatment with novel agents versus retreatment with platinum. ⋯ The acquired resistance to cisplatin in A2780 is potentially due to P-glycoprotein-mediated multidrug resistance. This acquired resistance to cisplatin is an unstable phenotype in that some cell populations become sensitive after a drug-free interval and topotecan treatment. This reversal of resistance, however, does not appear to be simply due to loss of MDR-1 expression. While in vivo confirmation is required, agents with novel mechanisms of action offer a strategy to extend the platinum-free interval and thereby improve survival in patients with recurrent ovarian cancer.