Effects of insulin-like growth factor binding protein 7 on apoptosis in human teratocarcinoma cells in vitro

Abstract

Human teratocarcinoma cells (Tera-2) deprived of serum undergo programmed cell death which can be counteracted by simultaneous addition of IGF-II. This protective effect of IGF-II was specific in the sense that addition of IGF-binding protein 7 (IGFBP-7) resulted in an increased apoptotic rate almost comparable to that of the classical IGFBPs. Autoradiographic analysis of incorporated tritiated thymidine indicated that the proportion of S-phase cells was comparable, irrespective of total cell numbers. This further suggests that IGF-II rescues cells from apoptosis and that IGFBP-7 is a specific antagonist.