CCL2 and neoplasm: However, when crossed with EC-Gαs-KO mice to generate inducible endothelium-specific Gαs/CCL2 double-deficient mice (EC-Gαs/Ccl2-dKO) we found that loss of endothelial CCL2 normalized the tumor phenotype of EC-Gαs-KO animals (Fig. 8 b).