PI4KA and cancer: In prostate tumors, PI4KA is overexpressed in metastasis 34 and the higher levels of PIP2 in cancer cells is due high activity of PI4KA and efficient subsequent conversion of PI4P to PI(4,5)P2, and PI(3,4)P2. PI(4,5)P2 is the second abundant PtdIns species in cells, and its levels increased 4 to 5 folds in tumor cells.