TNF-alpha induces apoptosis mediated by AEBSF-sensitive serine protease(s) that may involve upstream caspase-3/CPP32 protease activation in a human gastric cancer cell line.
In the present study, we investigated the role of caspase-3/CPP32 and serine protease(s) in cell death induced by TNF-alpha in SNU-16 human gastric adenocarcinoma cells. Apoptosis induced in SNU-16 cells by TNF-alpha was accompanied by the activation of caspase-3/CPP32. After treatment with TNF-alpha, PKCdelta cleaved to its characteristic 40 kDa fragment in a caspase-3/CPP32 dependent manner. Incubation with z-DEVD-fmk completely abrogated TNF-alpha-induced DNA fragmentation, indicating that activation of caspase-3/CPP32 was crucially involved in TNF-alpha-induced apoptosis. In addition, serine protease inhibitor, 4-(2-aminoethyl)benzenesulfonyl fluoride (AEBSF), clearly inhibited all the features of apoptosis including DNA fragmentation and chromatin condensation. Furthermore, in the AEBSF treated SNU-16 cells, only intact PKCdelta was detected by immunoblot analysis, suggesting that activation of caspase-3/CPP32 was blocked. Thus, the AEBSF-sensitive step may involve an upstream caspase-3/CPP32 protease activation. Taken together, these results suggest that both caspase-3/CPP32 and serine protease(s) are activated and play an important role in TNF-alpha induced apoptosis in SNU-16 cells.
Park
I C
IC
Laboratory of Cell Biology, Korea Cancer Center Hospital, Nowon-gu, Seoul 139-706, Korea.
Park
M J
MJ
Choe
T B
TB
Jang
J J
JJ
Hong
S I
SI
Lee
S H
SH
D000230:Adenocarcinoma / Q000378:metabolism* / Q000503:physiopathology; D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology; D053148:Caspase 3; D020169:Caspases / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D009363:Neoplasm Proteins / Q000187:drug effects* / Q000378:metabolism; D015842:Serine Proteinase Inhibitors / Q000494:pharmacology*; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000503:physiopathology; D013450:Sulfones / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D009363:Neoplasm Proteins; D015842:Serine Proteinase Inhibitors; D013450:Sulfones; D014409:Tumor Necrosis Factor-alpha; C002010:4-(2-aminoethyl)benzenesulfonylfluoride; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases