R36E + R37E

R36E + R37E (also written as R36E/R37E) is an integrin-binding defective mutant of insulin-like growth factor-1 (IGF-1). It is a biologic (mutant protein/peptide) in which two arginine residues at positions 36 and 37 of IGF-1 are substituted with glutamate, abolishing IGF-1's ability to bind integrins (αvβ3 and α6β4) while retaining binding to the IGF-1 receptor (IGF1R). Because it binds IGF1R without triggering the full ternary complex (integrin–IGF1–IGF1R) required for downstream signaling, it acts as a dominant-negative antagonist (decoy) of IGF1R signaling. In preclinical studies, it has been shown to suppress tumorigenesis in vivo across multiple cancer cell lines (breast cancer, colon cancer, melanoma), while wild-type IGF-1 markedly enhanced tumor growth. It has no known brand name, no identified commercial developer, and has not been approved by any regulatory agency. It appears to be a purely academic/research tool compound.

Other names

integrin-binding defective mutant of insulin-like growth factor-1R36E + R37ER36E/R37ER36E/R37E IGF-1R36E/R37E mutant of insulin-like growth factor-1