IGFBP3 (Insulin-Like Growth Factor Binding Protein 3) is a protein that binds to insulin-like growth factors (IGFs), regulating their availability and activity in the body. This control affects cell growth, development, and metabolism. IGFBP3 is extensively studied in cancer research because it can either inhibit or enhance IGF effects depending on the cellular environment, making it a key factor in tumor growth and potential therapeutic strategies.