UFH and LMWH suppress VEGF release from human platelets after exposure to MCF-7 cells or ADP. (A) VEGF concentration in releasate generated from platelets resting or exposed to MCF-7 cells after exposure to UFH or LMWH. (B) VEGF concentration in the releasate generated from platelets activated with 25 μM ADP after exposure to UFH or LMWH. (C) Immunofluorescence of platelets resting, exposed to MCF-7 cells, or activated with 25 μM ADP after exposure to UFH or LMWH and labeled with endostatin (red) or VEGF (green). *P < .05. Bars represent 2 μM.