MCF-7 breast cancer cells treated with exogenous IGFBP-3 showed increased apoptosis and this effect could be reversed by the use of non-IGFBP-binding IGF-1analog but not IGF-1 strongly indicating that IGFBP-3 induced apoptosis by sequestering IGF-1 from the receptor (Nickerson et al., 1997). This evidence concerns the gene IGF1 and breast cancer.