Increased cell surface protease activity in UV-irradiated cells undergoing apoptosis.
UVB-irradiated HeLa cells undergoing apoptosis have increased cell surface protease (CSP) activity compared to viable or necrotic cells. In order to elucidate whether caspase 3 plays a role in the activation of CSP in cells undergoing apoptosis, HeLa cell cultures were pre-treated with the caspase inhibitor, DEVD, prior to being exposed to 500 Jm(-2) UVB. DEVD significantly inhibited caspase 3 activity in cells undergoing apoptosis, but did not affect the activation of CSP in these cells. The findings suggest that the activation of CSP in apoptotic cells is unrelated to caspase 3 activity.
Cancer Unit, Queensland Institute of Medical Research, Brisbane, Australia. t.piva@cqu.edu.au
T J
TJ
Piva
C M
CM
Davern
C M
CM
Winterford
K A
KA
Ellem
D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D002462:Cell Membrane / Q000201:enzymology*; D002470:Cell Survival / Q000528:radiation effects; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D010450:Endopeptidases / Q000378:metabolism* / Q000528:radiation effects; D006367:HeLa Cells; D006801:Humans; D007930:Leucine / Q000031:analogs & derivatives / Q000494:pharmacology; D009336:Necrosis; D014466:Ultraviolet Rays
D015853:Cysteine Proteinase Inhibitors; D010450:Endopeptidases; D007930:Leucine; C012211:ubenimex