Insulin Like Growth Factor Binding Protein 3 (IGFBP3)

The protein forms a ternary complex with insulin-like growth factor acid-labile subunit (IGFALS) and either insulin-like growth factor (IGF) I or II. In this form, it circulates in the plasma, prolonging the half-life of IGFs and altering their interaction with cell surface receptors.

IGFBP3 protein levels decrease during the progression of prostate cancer from benign prostatic hyperplasia (BPH) to its metastatic form.Although, production of the protein does not cease completely. IGFBP3 is still made (at a lower level) by prostate cancer cells and secreted into the surrounding environment. However, instead of the full length, functional protein, IGFBP3 is found to be cleaved.