IGFBP1 and cancer: In line with this hypothesis, studies have previously shown that, in addition to changing the IGF ligand half-lives and modulating their interaction with the IGF receptors, IGFBP-1 and IGFBP-2 can directly promote cancer development by interacting with the α5/β1 integrin receptor or suppressing the expression of E-cadherin [27,28,29].