Cathepsin A activity in primary and metastatic human melanocytic tumors.

Abstract

Several lysosomal proteases including cathepsins B, D, H and L have been found to play a role in the metastasis of tumor cells. However, up to now no information on the role of cathepsin A, a lysosomal multifunctional peptidase, in the proliferative, invasive, and metastatic potential of malignant tumors has been available. In the present study we compared the activity of cathepsin A in lysates of 34 human melanocytic tumors: primary (n = 12) and metastatic (n = 5) malignant melanoma, dysplastic pigmented nevi (n = 6) and pigmented nevi without evidence of dysplastic melanocytes (n = 11). The carboxypeptidase activity of cathepsin A was assayed at pH 5.0 with its specific substrate Cbz-Phe-Ala. The amount of released C-terminal alanine was measured by the ninhydrin method. We found that lysates of primary malignant melanoma lesions exhibited significantly higher cathepsin A activity than lysates of dysplastic and normal pigmented nevi. The cathepsin A activity in lysates of metastatic lesions of malignant melanoma was significantly higher than in primary focus lysates. It seems that cathepsin A may play a role in malignant transformation and metastatic dissemination of malignant melanoma.

• Authors: L Kozlowski, M Z Wojtukiewicz, H Ostrowska
• Journal: Archives of dermatological research (Arch Dermatol Res) 2000 Feb-Mar Vol. 292 Issue 2-3 Pg. 68-71 ISSN: 0340-3696 [Print] Germany
• PMID: 10749558 (Publication Type: Journal Article)

Chemical References

• Carboxypeptidases
• CTSA protein, human
• Cathepsin A

Topics

• Carboxypeptidases (metabolism)
• Cathepsin A
• Humans
• Melanoma (enzymology, secondary)