Growth factor-induced release of a glycosyl-phosphatidylinositol (GPI)-linked protein from the HEp-2 human carcinoma cell line.

The release of a GPI-linked oncofetal protein (PLAP) from HEp-2 cells has been studied as an indicator of endogenous PI-specific PLC activation. A non-hydrolysable GTP analogue, EGF and insulin all produced a dose-dependent release of PLAP from these cells. This indicates that an increase in PLC activity following either growth factor binding or G protein activation may cause cellular release of PLAP.