The extracellular matrix protein fibronectin is a substrate for kallikrein 7.

Abstract

Kallikrein 7 (hK7), a chymostatin-like serine protease, is overexpressed in pancreatic adenocarcinomas as well as other human cancers. Although it has been demonstrated to participate in normal desquamation by facilitating cell shedding at the skin surface, its role in human malignancies remains unclear. To investigate the ability of hK7 to degrade components of the extracellular matrix (ECM), recombinant hK7 was expressed and purified from cultured mammalian cells. Using a three-step chromatographic purification procedure, recombinant hK7 was obtained that displayed robust proteolytic activity against a fluorogenic peptide substrate following activation by thermolysin. We demonstrate that the active protease is able to cleave fibronectin in a time-dependent manner, but not laminin, using an in vitro degradation assay. These findings indicate that the aberrant expression and secretion of hK7 in human tumors may facilitate metastasis by directly degrading components of the extracellular matrix and may thus play an important role in tumorigenesis.

• Authors: Vishnu C Ramani, Randy S Haun
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 369 Issue 4 Pg. 1169-73 (May 16 2008) ISSN: 1090-2104 [Electronic] United States
• PMID: 18343220 (Publication Type: Journal Article)

Chemical References

• Fibronectins
• Recombinant Proteins
• KLK7 protein, human
• Kallikreins
• Thermolysin

Topics

• Cell Line
• Chromatography (methods)
• Extracellular Matrix (metabolism)
• Fibronectins (chemistry, metabolism)
• Humans
• Kallikreins (chemistry, genetics, metabolism)
• Neoplasms (enzymology)
• Recombinant Proteins (biosynthesis, chemistry, isolation & purification)
• Substrate Specificity
• Thermolysin (metabolism)