Expression and activity of proteases in metastasis of ovarian cancer

Abstract

The total chymotrypsin like activity of proteasomes, the activity of 20S and 26S proteasome pools and calpains, and the expression of metalloproteinase PAPP A in primary tumors and metastasized tis sues were studied in 13 patients with epithelial ovarian cancer. It was shown that initiation of the process of tumor dissemination occurs against the background of active proteolytic processes. A decrease in activity of 26S proteasomes and total calpain activity and increased expression of metalloproteinase PAPP A in the pri mary tumors were found in patients with ascites as compared with patients without ascites. The disease pro gression after treatment and achieved stabilization were found in patients with decreased activity of intracel lular proteases and a high content of PAPP A in the primary tumors.

The fucosylated CD147 enhances the autophagy in epithelial ovarian cancer cells

“…This result is consistent with the conclusions in our study; both results are also consistent with the latest studies on the use of proteasome inhibitors in the targeted tumor therapy. Iunusova et al reported that 26S-proteasome and calpain activity were both decreased in tissue specimens from ovarian cancer patients with ascites, making it difficult to form definitive conclusions regarding the role of proteasomes in the malignant progression of ovarian cancer [ 15 ]. However, the data do demonstrate that at the early stages of autophagy, the activity of the peptidyl glutamyl-peptide hydrolase-like and chymotrypsin-like proteasomes were increased in ovarian cancer cells of high-grade malignancy, but when excessive autophagy of cells was induced by external and internal harsh environments autophagic death occurred in a large number of cells and the activities of trypsin-like and peptidyl glutamyl-peptide hydrolase-like proteasomes were decreased.…”