The gallium complex KP46 sensitizes resistant leukemia cells and overcomes Bcl-2-induced multidrug resistance in lymphoma cells via upregulation of Harakiri and downregulation of XIAP in vitro

Author(s)
Nicola L. Wilke, Liliane Onambele Abodo, Corazon Frias, Jerico Frias, Jennifer Baas, Michael A. Jakupec, Bernhard K. Keppler, Aram Prokop
Abstract

Tris-(8-quinolinolato)gallium(III) (KP46, AP-002) is an orally administered investigational anticancer and bone-protective drug currently being evaluated in patients with advanced solid tumors with bone involvement. Despite the clinical efficacy of other gallium compounds in non-Hodgkin's lymphoma, effects of KP46 in hematological tumor settings have not been studied systematically before. We report here intriguing activities in various human cell lines, including such with multidrug resistance (MDR): In Nalm-6 lymphoblastic leukemia cell sublines, KP46 was capable of overcoming P-gp-related as well as P-gp-unrelated MDR. Apoptosis induction by KP46 was unaffected by bcl2-mediated vincristine-induced MDR in a BJAB lymphoma cell subline and even enhanced in a K562 leukemia subline with daunorubicin-induced MDR, which could be re-sensitized to daunorubicin by KP46. As the latter resistance is associated with lowered Harakiri (HRK) protein levels, a modulating effect of KP46 on HRK expression is suggested. This is consistent with the significant high upregulation of HRK on RNA and protein levels observed in KP46-treated parental BJAB cells according to qPCR and Western blot analysis, respectively. Furthermore, KP46 significantly reduces the protein level of X-linked inhibitor of apoptosis (XIAP) in BJAB cells, the most potent known inhibitor of apoptosis. Overall, these results indicate both a higher potential of HRK and XIAP as cellular targets for cancer therapy and a broader therapeutic potential of KP46 than hitherto envisaged.

Organisation(s)
Department of Inorganic Chemistry
External organisation(s)
Helios Clinics Schwerin, Research Cluster Translational Cancer Therapy Research, Childrens Hosp Cologne, Dept Paedriat Oncol
Journal
Biomedicine and Pharmacotherapy
Volume
156
ISSN
0753-3322
DOI
https://doi.org/10.1016/j.biopha.2022.113974
Publication date
12-2022
Peer reviewed
Yes
Austrian Fields of Science 2012
206001 Biomedical engineering, 301206 Pharmacology, 301904 Cancer research
Keywords
ASJC Scopus subject areas
Pharmacology
Sustainable Development Goals
SDG 3 - Good Health and Well-being
Portal url
https://ucrisportal.univie.ac.at/en/publications/ec357f69-71f5-4b77-a1b4-1e45d2e15816