VEGFA and neoplasm: Similar quantities of VEGF were detected in cell lysates and conditioned media from vector control and GPNMB/OA expressing 66cl4 cells (Supplemental Figure S2 A, B); however, tumors derived from GPNMB/OA expressing cells (mean 652ng/ml) produced nearly twice as much VEGF as vector control tumors (mean = 328 ng/mL), suggesting that GPNMB/OA may indirectly upregulate VEGF in vivo via interactions with stromal cells in the tumor microenvironment (Supplemental Figure S2C).