Impact of Stepwise NH2-Methylation of Triapine on the Physicochemical Properties, Anticancer Activity, and Resistance Circumvention

Author(s)
Christian R. Kowol, Walter Miklos, Sarah Pfaff, Sonja Hager, Sebastian Kallus, Karla Pelivan, Mario Kubanik, Eva A. Enyedy, Walter Berger, Petra Heffeter, Bernhard K. Keppler
Abstract

One of the most promising classes of iron chelators are α-N-heterocyclic thiosemicarbazones with Triapine as the most prominent representative. In several clinical trials Triapine showed anticancer activity against hematological diseases, however, studies on solid tumors failed due to widely unknown reasons. Some years ago, it was recognized that "terminal dimethylation" of thiosemicarbazones can lead to a more than 100-fold increased activity, probably due to interactions with cellular copper depots. To better understand the structural requirements for the switch to nanomolar cytotoxicity, we systematically synthesized all eight possible N-methylated derivatives of Triapine and investigated their potential against Triapine-sensitive as well as -resistant cell lines. While only the "completely" methylated compound exerted nanomolar activity, the data revealed that all compounds with at least one N-dimethylation were not affected by acquired Triapine resistance. In addition, these compounds were highly synergistic with copper treatment accompanied by induction of reactive oxygen species and massive necrotic cell death.

Organisation(s)
Department of Inorganic Chemistry
External organisation(s)
Medizinische Universität Wien, University of Szeged
Journal
Journal of Medicinal Chemistry
Volume
59
Pages
6739-6752
No. of pages
14
ISSN
0022-2623
DOI
https://doi.org/10.1021/acs.jmedchem.6b00342
Publication date
07-2016
Peer reviewed
Yes
Austrian Fields of Science 2012
301904 Cancer research, 301305 Medical chemistry
Keywords
ASJC Scopus subject areas
Drug Discovery, Molecular Medicine
Sustainable Development Goals
SDG 3 - Good Health and Well-being
Portal url
https://ucrisportal.univie.ac.at/en/publications/787de56c-b217-4a01-9574-c8f0b5cc598e