@article{oai:repo.qst.go.jp:00043264,
 author = {Nenoi, Mitsuru and Ichimura, Sachiko and Mita, Kazuei and Yukawa, Osami and L., Cartwright Iain and 根井 充 and 沼田 幸子 and 三田 和英 and 湯川 修身},
 journal = {Cancer Research},
 month = {Aug},
 note = {Reactive oxygen species play a critical role in the onset of apoptosis induced by various extracellular stimuli, including ionizing radiation. Therefore active regulation of reactive oxygen species-metabolizing enzymes may be one response to an apoptotic stimulus. In this regard, HP100 cells, H(2)O(2)-resistant variants derived from human leukemia HL60 cells, display an interesting phenotype in which the activity of catalase is constitutively high, whereas its mRNA is reduced after X-ray irradiation. In the present study, we investigated the molecular mechanisms underlying this phenomenon. By combining analyses from nuclear run-on, reporter gene transient transfection, genomic footprinting, site-directed mutagenesis, electrophoretic mobility shift analysis, and Western blotting experiments, we found that constitutively elevated catalase expression is strongly regulated at the transcriptional level by both Sp1 and CCAAT-recognizing factors and that much higher levels of nuclear Sp1 and NF-Y are present in HP100 nuclei as compared with HL60 nuclei. In addition, we demonstrated an X-ray-inducible association of a WT1/Egr-related factor with an overlapping Sp1/Egr-1 recognition sequence located within the core promoter of the catalase gene. This association may lead to inactivation of the promoter by disturbing or competing with the transactivating ability of Sp1.},
 pages = {5885--5894},
 title = {Regulation of the catalase gene promoter by Sp1, CCAAT-recognizing factors,},
 volume = {61},
 year = {2001}
}