A method of inhibiting cellular activation by Insulin-like Growth Factor-1 (IGF-1) in a subject in need thereof (e.g., a subject afflicted with cancer, atherosclerosis, diabetic retinopathy or other disease) comprises administering an antagonist that inhibits the binding of IAP to SHPS-1 to the subject in an amount effective to inhibit cellular activation by IGF-1. Compounds and compositions for carrying out such methods are also described.