ABSTRACT
Proteinases are known to be involved in carcinogenesis, and various substrates are now available to measure the activity of these enzymes. No suitable serum tumour marker for head and neck squamous cell carcinoma (HNSCC) exists at this moment. Therefore, we compared proteinase-activity in serum of 20 untreated HNSCC patients with that of 20 non-cancer individuals. When N-benzoyl-DL-arginine-beta-naphtylamide (BANA) was used as the substrate, proteinase-activity seemed higher among patients, but this difference disappeared after adjustment for alcohol and tobacco consumption. Applying N-a-benzoyloxycarbonyl-L-arginyl-L-arginine-7-amido-4-methylcou marine (ZAAM) as the substrate no difference was found. Addition of E-64, an inhibitor of cysteine proteinase showed that cathepsin B contributed minimally to the ZAAM-specific activity.
Subject(s)
Alcohol Drinking/metabolism , Biomarkers, Tumor/blood , Carcinoma, Squamous Cell/enzymology , Endopeptidases/blood , Head and Neck Neoplasms/blood , Smoking/metabolism , Adult , Aged , Benzoylarginine-2-Naphthylamide/metabolism , Coumarins/metabolism , Cysteine Proteinase Inhibitors/pharmacology , Dipeptides/metabolism , Female , Humans , Leucine/analogs & derivatives , Leucine/pharmacology , Male , Middle Aged , Substrate SpecificitySubject(s)
Parkinson Disease/enzymology , Peptidyl-Dipeptidase A/cerebrospinal fluid , Aged , Albumins/cerebrospinal fluid , Atrophy/drug therapy , Atrophy/enzymology , Dopamine/pharmacology , Female , Humans , Male , Middle Aged , Neurons/pathology , Parkinson Disease/drug therapy , Peptidyl-Dipeptidase A/drug effectsABSTRACT
Angiotensin-converting enzyme activity was measured in lumbar cerebrospinal fluid from patients with 'probable' Alzheimer's disease (n = 17) and age-matched controls (n = 19), using a spectrofluorimetric method. In contrast to a previous finding, no statistically significant difference in the mean (specific) angiotensin-converting enzyme activity was found between the two groups. No correlation existed between (specific) enzyme activity and severity of dementia in the Alzheimer's disease patients. We conclude that angiotensin-converting enzyme in cerebrospinal fluid does not appear to be useful as a potential antemortem marker for Alzheimer's disease.
