IGFBP3 and cancer: As an N‐linked glycosylated, phosphorylated and secreted protein, IGFBP3 has been demonstrated to inhibit cell proliferation and induce cell apoptosis of multiple common cancers, including prostate, breast, lung, and colorectal cancers (Gallagher & LeRoith, 2010; Renehan et al., 2004; Yu & Rohan, 2000).