Evaluation of carbonic anhydrase IX as a therapeutic target for inhibition of breast cancer invasion and metastasis using a series of in vitro breast cancer models

// Carol Ward 1 , James Meehan 1 , Peter Mullen 2 , Claudiu Supuran 3 , J. Michael Dixon 4 , Jeremy S. Thomas 5 , Jean-Yves Winum 6 , Philippe Lambin 7 , Ludwig Dubois 7 , Nanda-Kumar Pavathaneni 6, 7 , Edward J. Jarman 1 , Lorna Renshaw 4 , InHwa Um 2 , Charlene Kay 1 , David J. Harrison 2 , Ian H. Kunkler 8 , Simon P. Langdon 1 1 Division of Pathology, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom 2 School of Medicine, University of St Andrews, North Haugh, St Andrews, United Kingdom 3 Universita degli Studi di Firenze, Polo Scientifico, Laboratorio di Chimica Bioinorganica, Sesto Fiorentino, Florence, Italy 4 Edinburgh Breast Unit, Western General Hospital, Edinburgh, United Kingdom 5 Department of Pathology, Western General Hospital, Edinburgh, United Kingdom 6 Institut des Biomolecules Max Mousseron (IBMM), UMR 5247, CNRS-UM1-UM2, Batiment de Recherche Max Mousseron, Ecole Nationale Superieure de Chimie de Montpellier, Montpellier, France 7 Department of Radiation Oncology (MaastRO), GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center (MUMC+), Maastricht, The Netherlands 8 Edinburgh Cancer Research Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom Correspondence to: Carol Ward, e-mail: drcward@hotmail.co.uk Keywords: carbonic anhydrase IX, breast cancer, tumour microenvironment, invasion, hypoxia Received: May 11, 2015 Accepted: June 22, 2015 Published: July 04, 2015 ABSTRACT Triple negative, resistant or metastatic disease are major factors in breast cancer mortality, warranting novel approaches. Carbonic anhydrase IX (CAIX) is implicated in survival, migration and invasion of breast cancer cells and inhibition provides an innovative therapeutic strategy. The efficacy of 5 novel ureido-substituted sulfamate CAIX inhibitors were assessed in increasingly complex breast cancer models, including cell lines in normoxia and hypoxia, 3D spheroids and an ex-vivo explant model utilizing fresh biopsy tissue from different breast cancer subtypes. CAIX expression was evaluated in a tissue microarray (TMA) of 92 paired lymph node and primary breast cancers and 2 inhibitors were appraised in vivo using MDA-MB-231 xenografts. FC11409B, FC9398A, FC9403, FC9396A and S4 decreased cell proliferation and migration and inhibited 3D spheroid invasion. S4, FC9398A and FC9403A inhibited or prevented invasion into collagen. FC9403A significantly reversed established invasion whilst FC9398A and DTP348 reduced xenograft growth. TMA analysis showed increased CAIX expression in triple negative cancers. These data establish CAIX inhibition as a relevant therapeutic goal in breast cancer, targeting the migratory, invasive, and metastatic potential of this disease. The use of biopsy tissue suggests efficacy against breast cancer subtypes, and should provide a useful tool in drug testing against invasive cancers.