Elastase activities of human bladder cancer cell lines derived from high grade invasive tumours.
Elastase activities in intact human bladder cancer cell lines, established from three patients, were measured using a fluorogenic substrate highly specific for elastase, under conditions of physiological pH and ionic strength. This method allowed separation of cell-associated from secreted enzyme activity. As secreted elastase accounted for only 8% of the total, we concluded that the elastases were present at the cell surface. Inhibition studies using extracts of cell-surface elastases showed them to be serine proteinases which were also inhibited by alpha 1-antitrypsin. Partially purified fractions showing the highest specific activity towards the fluorogenic substrate hydrolysed insoluble elastin thus confirming the presence of elastases. This is the first time that elastase activity has been demonstrated in human bladder cancer cells and may represent a mechanism involved in tumour invasion.
Grant
A J
AJ
Urological Cancer Research Unit, Royal Prince Alfred Hospital, Sydney, Australia.
Russell
P J
PJ
Raghavan
D
D
D000409:Alanine / Q000031:analogs & derivatives; D000818:Animals; D002295:Carcinoma, Transitional Cell / Q000201:enzymology* / Q000378:metabolism / Q000473:pathology; D002460:Cell Line; D003374:Coumarins; D006801:Humans; D008565:Membrane Proteins / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism; D051379:Mice; D008819:Mice, Nude; D009361:Neoplasm Invasiveness; D009368:Neoplasm Transplantation; D010196:Pancreatic Elastase / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D011480:Protease Inhibitors; D013379:Substrate Specificity; D001749:Urinary Bladder Neoplasms / Q000201:enzymology* / Q000378:metabolism / Q000473:pathology
D003374:Coumarins; D008565:Membrane Proteins; D011480:Protease Inhibitors; C056142:N-acetylalanine alpha-naphthyl ester; D010196:Pancreatic Elastase; C028743:7-amino-4-methylcoumarin; D000409:Alanine