Section Review: Oncologic, Endocrine & Metabolic: Topoisomerase I inhibitors in gynaecologic cancers

The topoisomerases are cellular enzymes with a variety of biochemical functions, involving DNA replication, RNA transcription, DNA repair, and mitosis. The topoisomerase inhibitors are emerging as very potent anticancer agents, with activity in refractory tumours. The camptothecin analogues have been the most studied drugs. Two classes have been defined: the water-soluble camptothecins and the water-insoluble camptothecins. Their activity is dependent upon their molecular structure; the active form has a closed lactone E ring. This review focuses on the early (Phase l/ll) clinical trials with these compounds and discusses their use in the treatment of gynaecological cancers.