NECTIN4 and neoplasm: The interaction between soluble Nectin-4 and integrin β4 on endothelial cells can regulate the transcriptional activity of Src, PI3K, AKT, and endothelial NO synthase, inducing the formation of NO mediated by the PI3K/AKT signaling pathway, thereby promoting tumor angiogenesis (Zhang et al., 2019; Siddharth et al., 2018).