Figure 9.

Model for WNK1 and VEGF interaction in angiogenesis and tumor growth. Tumor produces VEGF and WNK1, and both act to stimulate endothelial cells to form new blood vessels. WNK1 stimulates angiogenesis through downstream kinase OSR1. VEGF-stimulated angiogenesis is at least partly through PI3K/AKT-induced phosphorylation of WNK1. Three positive feedback loops participate in amplification of tumor growth: (1) angiogenesis providing nutrient for tumor to grow, (2) direct proliferative effect of WNK1 on tumor cells, and (3) expression of WNK1 from tumor or other tissues (dotted line) stimulated by VEGF.