CA 074

CA-074, a specific cathepsin B inhibitor, also abolished the neurotoxic effects caused by Abeta42-activated BV2 cell [1]. Co-treatment of cultures with the cathepsin B inhibitors CA-074 or Z-FA-FMK suppressed the cytostatic effects of TPA and activation of pro-uPA [2]. Administration of CA-074 suppresses the response to exogenous antigens, such as hepatitis B virus antigen, ovalbumin and Leishmania major antigen, and induces switching of the helper T cell responses from Th-2 to Th-1 of CD4+ T cell, thereby down regulating the production of IgE and IgG1 [3]. Pharmacological inhibition of cat B in catB(+/+) mice with L-3-trans-(propylcarbamoyl)oxirane-2-carbonyl-Lisoleucyl-L-proline (CA-074 Me) also reduced TNF-alpha-induced liver damage. [4] Administration of cathepsin B inhibitors, E-64, CA-074 and vitamin B6, caused the strong suppression of the Th-2 type immune responses .

 Inhibitor of cathepsin B (Ki = 2-5 nM). Displays selectivity over cathepsins H and L (Ki = 40-200 μM). Shown to reduce bone metastasis in a 4T1.2 breast cancer model.

References:
1. Identification of cathepsin B as a mediator of neuronal death induced by Abeta-activated microglial cells using a functional genomics approach. Gan, L., Ye, S., Chu, A., Anton, K., Yi, S., Vincent, V.A., von Schack, D., Chin, D., Murray, J., Lohr, S., Patthy, L., Gonzalez-Zulueta, M., Nikolich, K., Urfer, R. J. Biol. Chem. (2004)
2. Phorbol ester activation of a proteolytic cascade capable of activating latent transforming growth factor-betaL a process initiated by the exocytosis of cathepsin B. Guo, M., Mathieu, P.A., Linebaugh, B., Sloane, B.F., Reiners, J.J. J. Biol. Chem. (2002)
3. Insights into the roles of cathepsins in antigen processing and presentation revealed by specific inhibitors. Katunuma, N., Matsunaga, Y., Himeno, K., Hayashi, Y. Biol. Chem. (2003)
4. Cathepsin B knockout mice are resistant to tumor necrosis factor-alpha-mediated hepatocyte apoptosis and liver injury: implications for therapeutic applications. Guicciardi, M.E., Miyoshi, H., Bronk, S.F., Gores, G.J. Am. J. Pathol. (2001)