FGFR1 and neoplasm: In bladder cancer, inflammatory CAFs (iCAFs) have the largest number of potential ligand–receptor pairs with other cell types, exhibiting particularly strong interactions with endothelial cells.194 VEGFA, VEGFB, and FGFR1, produced by iCAFs, bind to endothelial and tumor cells, suggesting that iCAFs promote the proliferation of tumor and stromal cells.