KGP94 is a novel, potent, reversible, time-dependent and competitive inhibitor of human cysteine protease Cathepsin L inhibitor(CTSL). It inhibits the activity of cathepsin L toward human type I collagen. KGP94
significantly impedes both migration and invasion of MDA-MB-231 human
breast cancer cells. Molecular modeling places the thiocarbonyl of KGP94 in proximity to the active site Cys25. Significant growth retardation of C3H mouse mammary carcinomas is achieved with KGP94 treatment [1,2]. KGP94 treatment led to marked attenuation of tumor cell invasion and
migration under both normal and aberrant microenvironmental conditions
suggesting that it may have significant utility as an anti-metastatic
agent. [3]