IGFBP7 and breast cancer: Nonetheless, IGFBP7, which contains an IGF-I receptor binding motif, was also reported to block IGF binding to its receptor and thus prevent the activation of downstream IGF-I receptor/Akt/Serine/threonine-protein kinase mTOR (mTOR)/Eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) pathway in breast cancer cells.