Interaction of the anticancer gallium(III) complexes of 8-hydroxyquinoline and maltol with human serum proteins

Author(s)
Eva A. Enyedy, Orsolya Doemoetoer, Krisztina Bali, Anasztazia Hetenyi, Tiziano Tuccinardi, Bernhard K. Keppler
Abstract

Tris(8-quinolinolato)gallium(III) (KP46) and tris(maltolato)gallium(III) (GaM) are promising orally active antitumor metallodrugs currently undergoing clinical trials. Their interaction with human serum albumin (HSA) and transferrin (Tf) was studied in detail in aqueous solution by the combination of various methods such as spectrofluorometry, UV-vis spectrophotometry, 1H and saturation transfer difference NMR spectroscopy, and ultrafiltration-UV-vis spectrophotometry. Binding data were evaluated quantitatively. Tf was found to replace the original ligand much less efficiently in KP46 than in GaM, whereas a significant noncovalent binding of KP46 with HSA (log K′ = 4.04) retaining the coordination environment around gallium(III) was found. The interaction between HSA and KP46 was also confirmed by protein-complex modeling calculations. On the basis of the conditional stability constants, the distribution of gallium(III) in serum was computed and compared for these metallodrugs under physiological conditions, and revealed the prominent role of HSA in the case of KP46 and that of Tf for GaM. Graphical abstract: [Figure not available: see fulltext.]

Organisation(s)
Department of Inorganic Chemistry
External organisation(s)
University of Szeged, University of Pisa
Journal
Journal of Biological Inorganic Chemistry
Volume
20
Pages
77-88
No. of pages
12
ISSN
0949-8257
DOI
https://doi.org/10.1007/s00775-014-1211-9
Publication date
01-2015
Peer reviewed
Yes
Austrian Fields of Science 2012
104003 Inorganic chemistry, 301904 Cancer research, 106023 Molecular biology, 301305 Medical chemistry
Keywords
ASJC Scopus subject areas
Biochemistry, Inorganic Chemistry
Sustainable Development Goals
SDG 3 - Good Health and Well-being
Portal url
https://ucrisportal.univie.ac.at/en/publications/ecb48aef-2a91-49a7-8265-8b176df41db4