GPNMB and neoplasm: Dissecting a possible mechanism of action, GPNMB has been reported to directly interact with EGFR, thus triggering a signaling cascade on its downstream targets, STAT3 and MMP2-3-9, and on VEGF and VCAM (Lin et al, 2016), suggesting that it may help creating a complex relationship between invading tumor and vasculature during tumor invasion.