文章基本信息

标题：Fas-independent Apoptosis Induced by UVC in p53-Mutated Human Epithelial Tumor A431 Cells through Activation of Caspase-8 and JNK/SAPK
其他标题：Fas-independent Apoptosis Induced by UVC in p53-Mutated Human Epithelial Tumor A431 Cells through Activation of Caspase-8 and JNK/SAPK
本地全文：下载
作者：HIROKO HAMA-INABA ; KEUN HEE CHOI ; BING WANG 等
期刊名称：Journal of Radiation Research
印刷版ISSN：0449-3060
电子版ISSN：1349-9157
出版年度：2001
卷号：42
期号：2
页码：201-215
DOI：10.1269/jrr.42.201
摘要：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.
关键词：A431 cells; UVC-induced apoptosis; Caspase 8; Fas; JNK; PAPK