Identification of signature genes associated with therapeutic resistance to anti-VEGF therapy
Pharavee Jaiprasart, Samrita Dogra, Deepika Neelakantan, Bharat Devapatla, Sukyung Woo
Abstract
// Pharavee Jaiprasart 1 , * , Samrita Dogra 1 , * , Deepika Neelakantan 1 , * , Bharat Devapatla 1 and Sukyung Woo 1 , 2 1 Department of Pharmaceutical Sciences, College of Pharmacy, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA 2 Gynecologic Cancers Research Program, Peggy and Charles Stephenson Cancer Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA * These authors contributed equally to this work Correspondence to: Sukyung Woo, email: [email protected] Keywords: anti-VEGF resistance; angiogenesis; bevacizumab; next-generation sequencing (NGS); apelin Received: May 21, 2019     Accepted: October 04, 2019     Published: January 07, 2020 ABSTRACT VEGF-mediated tumor angiogenesis is a validated clinical target in many cancers, but modest efficacy and rapid development of resistance are major challenges of VEGF-targeted therapies. To establish a molecular signature of this resistance in ovarian cancer, we developed preclinical tumor models of adaptive resistance to chronic anti-VEGF treatment. We performed RNA-seq analysis and reverse-phase protein array to compare changes in gene and protein expressions in stroma and cancer cells from resistant and responsive tumors. We identified a unique set of stromal-specific genes that were strongly correlated with resistance phenotypes against two different anti-VEGF treatments, and selected the apelin/APJ signaling pathway for further in vitro validation. Using various functional assays, we showed that activation of apelin/APJ signaling reduces the efficacy of a VEGF inhibitor in endothelial cells. In patients with ovarian cancer treated with bevacizumab, increased expression of apelin was associated with significantly decreased disease-free survival. These findings link signature gene expressions with anti-VEGF response, and may thus provide novel targetable mechanisms of clinical resistance to anti-VEGF therapies.