A New TIPE of Phosphoinositide Regulator in Cancer

Specific phosphoinositide lipids promote cell growth and cancer. In this issue of Cancer Cell , Fayngerts and colleagues demonstrate that the TIPE3 protein enhances PtdIns(4,5) P 2 and PtdIns(3,4,5) P 3 , is overexpressed in certain cancers, and promotes tumorigenesis. TIPE3 can act as a lipid transfer protein and may constitute a novel phosphoinositide metabolism regulator.