Accepted_test

Tyrosyl-DNA phosphodiesterase 1 (Tdp1) is a repair enzyme for “stalled” DNA-topoisomerase 1 (Top1) cleavage complexes and other 3' end DNA lesions. Tdp1 plays a crucial role in the repair of DNA lesions formed by antitumor drugs such as the Top1 inhibitors camptothecin, topotecan (a Top1 poison in clinical use), and irinotecan; therefore, Tdp1 is a promising target for adjunctive cancer treatment. Because homologs of Tdp1 have been present in organisms throughout most of evolution, there is a real possibility that natural biomolecules could have evolved to interact with this protein as well. In addition, a combination of antitumor and tumor chemosensitizing properties of drugs can lead to an enhanced therapeutic effect, and many natural compounds have intrinsic antitumor properties. Natural substances and compounds derived from natural pharmacophores are known to effectively disrupt many critical processes involved in the pathogenesis of many cancer types. Therefore, special attention is given to the search for inhibitors of Tdp1 among natural compounds and their derivatives.