Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.22.61 (caspase-8)
 6,833 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A431 cells/UVC-induced apoptosis/Caspase 8/Fas/JNK/PAPK. We previously observed that p53-mutated human epithelial tumor A431 cells underwent apoptosis after ultraviolet C (UVC) irradiation through the caspases-8 and -3 pathway. Fas/FasL is known to initiate apoptosis in several cell lines via caspase-8 activation. Then, to determine if Fas/FasL mediates apoptosis in A431. we investigated Fas expression and modulation in UVC-irradiated A431 cells. A431 constitutively expressed Fas, which gradually decreased after UVC-irradiation. Pretreatment with a neutralizing anti-Fas antibody, ZB4, did not abrogate the UVC-induced apoptosis. An agonistic anti-Fas antibody, CH11, very slowly induced apoptosis in A431. suggesting that the constitutively expressed Fas had a low functional potential. Hence, UVC-induced apoptosis in A431 seems to occur independent of the Fas signal. Interestingly, however, a pretreatment with CH11 remarkably potentiated UVC-induced apoptosis. An inhibitor of caspase-8, Ac-IETD-CHO, partially inhibited UVC-induced apoptosis. JNK was phosphorylated immediately after exposure to UVC. prior to apoptotic chromatin condensation. Our data suggest that the activation of caspase-8 occurs independent of Fas upregulation, and that JNK/ SAPK contributes to UVC-induced apoptosis in human epithelial A431 cells.
 ...
PMID:Fas-independent apoptosis induced by UVC in p53-mutated human epithelial tumor A431 cells through activation of caspase-8 and JNK/SAPK. 1159 86

Condyloma acuminatum (CA) is a benign epithelial tumor caused by infection with human papillomaviruses (HPVs) and characterized by abnormal cell proliferation. Cellular caspase-8 (FLICE)-like inhibitory protein (c-FLIP) was originally identified as an inhibitor of death-receptor signaling through competition with caspase-8 for recruitment to FAS-associated via death domain (FADD). More recently, it has been determined that c-FLIP is associated with the survival and proliferation of T cells and keratinocytes. The aim of this work was to study the expression of c-FLIP in CA and its relationship with keratinocyte proliferation. Immunoperoxidase staining methods were applied to analyze the location and expressions of both c-FLIP and proliferating cell nuclear antigens (PCNA) in 34 CA and 16 normal foreskin tissues. Semiquantitative reverse transcriptase-polymerase chain reactions (RT-PCR) and western blotting were performed to further identify the expression of c-FLIP in CA. c-FLIP expression at both mRNA and protein level was significantly higher in CA than normal foreskin. c-FLIP expression was highly correlated with the PCNA labeling index (LI) in CA. We concluded that c-FLIP overexpression might take part in keratinocyte proliferation in CA.
 ...
PMID:Increased expression of cellular FLICE/caspase-8 inhibitory protein in condyloma acuminatum. 2168 Feb 88