Proteinase-like peptidase activities in malignant and non-malignant gastric tissue.
Activities of several proteinase-like peptidases have been determined in homogenates of malignant tissue, non-malignant tissue adjacent to the tumour (A-NM) and non-malignant tissue distant to the tumour (D-NM) from 17 patients undergoing surgery for histologically confirmed gastric malignancies. In homogenates of malignant tissues the activities of collagenase, cathepsin B, cathepsin (B+L), cathepsin H and cathepsin D were significantly higher than in D-NM tissues. By contrast, the levels of plasminogen activator were significantly lower in malignant tissues than in the D-NM tissues. Furthermore, the activities of collagenase-like and the cysteine-proteinase-like peptidases in the A-NM tissues were lower than in malignant tissues but higher than in the D-NM tissues. Separation of full-thickness non-malignant tissues into mucosal and seromuscular layers revealed significantly higher activities in the former. The elevated levels of these proteinase-like peptidases in homogenates of gastric cancer tissue suggests an important role for these enzymes in tumour invasion.
D000368:Aged; D010450:Endopeptidases / Q000378:metabolism*; D005753:Gastric Mucosa / Q000378:metabolism; D006801:Humans; D008875:Middle Aged; D010447:Peptide Hydrolases / Q000378:metabolism; D013270:Stomach / Q000201:enzymology*; D013274:Stomach Neoplasms / Q000201:enzymology*
D010450:Endopeptidases; D010447:Peptide Hydrolases