Gold nanoparticles-based colorimetric assay for cathepsin B activity and the efficiency of its inhibitors.

Abstract

Cathepsin B has been suggested to be a prognostic marker of melanoma, glioma, and a variety of cancers such as brain, breast, colon, esophageal, gastric, lung, ovarian, and thyroid cancers. Cathepsin B inhibitors have also been considered as anticancer drug candidates; hence, there has been a growing need for a probe which enables the selective and simple detection of cathepsin B and its inhibitors. For the purpose of selective assay, a cathepsin B-specific substrate, N,N'-diBoc-dityrosine-glycine-phenylalanine-3-(methylthio)propylamine (DBDY-Gly-Phe-MTPA) was synthesized in this study. Phe-MTPA, which was produced via cathepsin B-catalyzed hydrolysis of DBDY-Gly-Phe-MTPA, allowed aggregatio..