title: p53-dependent and -independent regulation of the death receptor KILLER/DR5 gene expression in response to genotoxic stress and tumor necrosis factor alpha.
abstract: The death receptor (DR) KILLER/DR5 gene has recently been identified as a doxorubicin-regulated transcript that was also induced by exogenous wild-type p53 in p53-negative cells. KILLER/DR5 gene encodes a DR containing cell surface protein that is highly homologous to DR4, another DR of the tumor necrosis factor (TNF) receptor family. Both DR4 and KILLER/DR5 independently bind to their specific ligand TRAIL and engage the caspase cascade to induce apoptosis. TRID (also known as TRAIL-R3) is an antiapoptotic decoy receptor that lacks the cytoplasmic death domain and competes with KILLER/DR5 and DR4 for binding to TRAIL. In this study, we demonstrate that the DR KILLER/DR5 gene is regulated in a p53-dependent and -independent manner during genotoxic and nongenotoxic stress-induced apoptosis. Just like other p53-regulated genes, ionizing radiation induction of KILLER/DR5 occurs in p53 wild-type cells, whereas methyl methanesulfonate regulation of KILLER/DR5 occurs in a p53-dependent and -independent manner. However, unlike other p53-regulated genes, KILLER/DR5 is not regulated following UV irradiation. TNF-alpha, a nongenotoxic cytokine, also induced the expression of KILLER/DR5 in a number of cancer cell lines, irrespective of p53 status. TNF-alpha did not alter the KILLER/DR5 mRNA stability, suggesting that the TNF-alpha regulation of KILLER/DRS expression appears transcriptional. We also provide evidence that KILLER/DR5 is regulated in a trigger and cell type-specific manner and that its induction by TNF-alpha, p53, or DNA damage is not the consequence of apoptosis induced by these agents. Unlike KILLER/DR5, none of the other KILLER/DR5 family members, including DR4, TRID, or the ligand TRAIL, displayed genotoxic stress or TNF-alpha regulation in a p53 transcription-dependent manner. Thus, KILLER/DR5 appears a bona fide downstream target of p53 that is also regulated in a cell type-specific, trigger-dependent, and p53-independent manner.
authors.affiliation: Basic Research Laboratory, Division of Basic Sciences, National Cancer Institute, NIH, Bethesda, Maryland 20892, USA. mssheikh@box-m.nih.gov
authors.forename: M S
authors.initials: MS
authors.lastname: Sheikh
authors.forename: T F
authors.initials: TF
authors.lastname: Burns
authors.forename: Y
authors.initials: Y
authors.lastname: Huang
authors.forename: G S
authors.initials: GS
authors.lastname: Wu
authors.forename: S
authors.initials: S
authors.lastname: Amundson
authors.forename: K S
authors.initials: KS
authors.lastname: Brooks
authors.forename: A J
authors.initials: AJ
authors.lastname: Fornace
authors.forename: W S
authors.initials: WS
authors.lastname: el-Deiry
mesh_terms: D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins; D015152:Blotting, Northern; D004305:Dose-Response Relationship, Drug; D004317:Doxorubicin / Q000494:pharmacology; D058851:GPI-Linked Proteins; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects / Q000528:radiation effects; D006801:Humans; D015151:Immunoblotting; D008562:Membrane Glycoproteins / Q000378:metabolism; D008741:Methyl Methanesulfonate / Q000494:pharmacology; D012333:RNA, Messenger / Q000032:analysis; D011839:Radiation, Ionizing; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor / Q000378:metabolism*; D053320:Receptors, Tumor Necrosis Factor, Member 10c; D053221:TNF-Related Apoptosis-Inducing Ligand; D013997:Time Factors; D014162:Transfection; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000528:radiation effects; D053319:Tumor Necrosis Factor Decoy Receptors; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism / Q000494:pharmacology*; D016159:Tumor Suppressor Protein p53 / Q000502:physiology*; D014466:Ultraviolet Rays
chemical_list: D051017:Apoptosis Regulatory Proteins; D058851:GPI-Linked Proteins; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor; D053320:Receptors, Tumor Necrosis Factor, Member 10c; D053221:TNF-Related Apoptosis-Inducing Ligand; C105190:TNFRSF10A protein, human; C505639:TNFRSF10B protein, human; C108661:TNFRSF10C protein, human; C505653:TNFSF10 protein, human; D053319:Tumor Necrosis Factor Decoy Receptors; D014409:Tumor Necrosis Factor-alpha; D016159:Tumor Suppressor Protein p53; D004317:Doxorubicin; D008741:Methyl Methanesulfonate