Ptges was induced only in WT endothelial cells exposed to M27 cancer cells.Ptges gene (A) and protein (B) expression was increased in WT but not Gas6^−/− endothelial cells after culture with M27 cancer cells. (C) PGE₂, the enzymatic product of Ptges, was induced only in media of WT endothelial cells exposed to M27 cancer cells. *P < .05 comparing WT vs WT + M27; **P < .05 comparing WT + M27 vs Gas6^−/− + M27 and Gas6^−/− vs Gas6^−/− + M27. A.U., arbitrary units.