IGFBP3 and breast cancer: For instance, among IGFBPs (see “Introduction”), IGFBP-3 is the predominant binding partner for IGF-1 in the serum as compared with IGFBPs-1, IGFBPs-2, IGFBPs-4, IGFBPs-5, IGFBPs-6.54 This ability is simply due to the serum abundance of IGFBP-3,55 thereof the ternary complex of IGF-1, IGFBP-3, and an acid-labile subunit is principally seen to modulate antiproliferative activity in breast cancer.56 IGFBP-3 has been tested in preclinical models to inhibit IGF-action.57