Acts as a lipid transfer protein. Preferentially captures and shuttles two lipid second messengers, i.e., phosphatidylinositol 4,5- bisphosphate and phosphatidylinositol 3,4,5-trisphosphate and increases their levels in the plasma membrane. Additionally, may also function as a lipid-presenting protein to enhance the activity of the PI3K-AKT and MEK-ERK pathways. May act as a regulator of tumorigenesis through its activation of phospholipid signaling. On PDGF activation, translocates from cytoplasm to plasma membrane. Widely expressed (at protein level) (PubMed:25479791). Highly expressed in most carcinoma cell lines (PubMed:25479791, PubMed:25242044). Belongs to the TNFAIP8 family. It is uncertain whether Met-1 or Met-89 is the initiator.