Fig. 3

CD109 and EGFR/STAT3 signaling. CD109 facilitates EGFR signaling. The dimerized EGFR receptors phosphorylate c-Src, which in turn phosphorylates STAT3. CD109 may also activates STAT3 through phosphorylation of JAK2, then promote SCC cell growth, differentiation, and angiogenesis