Potential application of chymotrypsin-like proteasome activity as a biomarker for prostate cancer

Abstract:

Objective To investigate the feasibility of chymotrypsin-like proteasome（CLP） activity as a biomarker for prostate cancer.Methods Proteasome activity was determined in vitro and in vivo. We also measured the expression of inhibitory protein α of nuclear factor κB（IκB-α），Bcl-2 associated X protein（Bax），and cyclin-dependent kinase inhibitor（p27）.Results CLP activity was elevated by 70% in vitro and 23% in vivo，and the expression levels of the proteasome substrate proteins IκB-α，Bax，and p27 decreased in prostate cancer cells and prostate tumor xenografts compared with normal prostate epithelial cells and control mouse prostate tissue.Conclusion CLP activity is a potential biomarker for prostate cancer and may be used to supplement prostate-specific antigen in clinical diagnosis of prostate cancer.