Affiliation: Institute of Bioscience and Technology, Texas A&M University Health Science Center, 2121 West Holcombe Blvd., Houston, Texas 77030, USA.
G protein-coupled receptor 124 (GPR124; also called tumor endothelial marker 5, TEM5) is highly expressed in tumor vasculature. While recent studies have revealed a role in vasculogenesis, evidence for GPR124 function in tumor angiogenesis is lacking. Here, we demonstrate that GPR124 is required for VEGFinduced tumor angiogenesis. GPR124 silencing in human endothelial cells inhibited mouse xenograft tumor angiogenic vessel formation and tumor growth. GPR124 regulated VEGF-induced tumor angiogenic processes in vitro including cell-cell interaction, permeability, migration, invasion, and tube formation. Therefore, GPR124 plays a key role in VEGF-induced tumor angiogenesis.