Consistent with this, confocal detection of Cx43 gap junctions extending between mural cells and endothelial cells in co-culture, which seemed to preferentially form when mural cells oriented themselves over endothelial cells, was quantifiably decreased following treatment with tumor conditioned media (3.19+/−0.32 mock vs. 1.43+/−0.47 with 231 conditioned media, p = 0.01, Fig. 2d). Here, GJA1 is linked to neoplasm.