IGF1 and breast cancer: Further, culture medium from cells stimulated to undergo bone resorption was found to contain high concentrations of IGF-1; notably, the anchorage-independent growth of human BC cells cultured in this medium was inhibited by the IGF-1R–neutralizing antibody (Ab) αIR3, but not by Abs against TGF-β, FGF-1 or FGF-2, or PDGF-BB (Hiraga et al., 2012).