PKD1 and cancer: Furthermore, ECM breakdown results in the release of VEGF-A which is sequestered in the ECM upon secretion.24 In pancreatic and gastric tumor cells, PKD2 has also been shown to increase the angiogenic response to hypoxic conditions via its actions in both the endothelial cell as well as the cancer cell.28 PKD1 and 2 are both expressed in endothelial cells.