Novel fluorinated carbonic anhydrase IX inhibitors reduce hypoxia-induced acidification and clonogenic survival of cancer cells

Justina Kazokaitė; Raymon Niemans; Virginija Dudutienė; Holger M Becker; Jānis Leitāns; Asta Zubrienė; Lina Baranauskienė; Gabor Gondi; Reinhard Zeidler; Jurgita Matulienė; Kaspars Tārs; Ala Yaromina; Philippe Lambin; Ludwig J Dubois; Daumantas Matulis

doi:10.18632/oncotarget.25508

Novel fluorinated carbonic anhydrase IX inhibitors reduce hypoxia-induced acidification and clonogenic survival of cancer cells

Oncotarget. 2018 Jun 1;9(42):26800-26816. doi: 10.18632/oncotarget.25508.

Authors

Justina Kazokaitė^{1

2}, Raymon Niemans², Virginija Dudutienė¹, Holger M Becker³, Jānis Leitāns⁴, Asta Zubrienė¹, Lina Baranauskienė¹, Gabor Gondi^{5

6}, Reinhard Zeidler^{5

6}, Jurgita Matulienė¹, Kaspars Tārs¹, Ala Yaromina², Philippe Lambin², Ludwig J Dubois^#², Daumantas Matulis^#¹

Affiliations

¹ Department of Biothermodynamics and Drug Design, Institute of Biotechnology, Vilnius University, Vilnius, Lithuania.
² Department of Radiotherapy (The M-Lab Group), GROW - School for Oncology and Developmental Biology, Maastricht Comprehensive Cancer Centre, Maastricht University Medical Centre, Maastricht, The Netherlands.
³ Department of Physiological Chemistry, University of Veterinary Medicine Hannover, Hannover, Germany.
⁴ Latvian Biomedical Research and Study Center, Riga, Latvia.
⁵ Department of Gene Vectors, Helmholtz Center for Environmental Health, Munich, Germany.
⁶ Department of Otorhinolaryngology, Klinikum der Universität München, Munich, Germany.

^# Contributed equally.

Abstract

Human carbonic anhydrase (CA) IX has emerged as a promising anticancer target and a diagnostic biomarker for solid hypoxic tumors. Novel fluorinated CA IX inhibitors exhibited up to 50 pM affinity towards the recombinant human CA IX, selectivity over other CAs, and direct binding to Zn(II) in the active site of CA IX inducing novel conformational changes as determined by X-ray crystallography. Mass spectrometric gas-analysis confirmed the CA IX-based mechanism of the inhibitors in a CRISPR/Cas9-mediated CA IX knockout in HeLa cells. Hypoxia-induced extracellular acidification was significantly reduced in HeLa, H460, MDA-MB-231, and A549 cells exposed to the compounds, with the IC₅₀ values up to 1.29 nM. A decreased clonogenic survival was observed when hypoxic H460 3D spheroids were incubated with our lead compound. These novel compounds are therefore promising agents for CA IX-specific therapy.

Keywords: cancer; carbonic anhydrase IX; drug design; hypoxia; sulfonamide.