1
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Jeon SJ, Chung KC. Covalent conjugation of ubiquitin-like ISG15 to apoptosis inducing factor exacerbates toxic stimuli-induced apoptotic cell death. J Biol Chem 2022; 298:102464. [PMID: 36075291 PMCID: PMC9547223 DOI: 10.1016/j.jbc.2022.102464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 08/27/2022] [Accepted: 08/29/2022] [Indexed: 11/26/2022] Open
Abstract
Apoptosis-inducing factor (AIF) is a mitochondrion-localized flavoprotein with NADH oxidase activity. AIF normally acts as an oxidoreductase to catalyze the transfer of electrons between molecules, but it can also kill cells when exposed to certain stimuli. For example, intact AIF is cleaved upon exposure to DNA-damaging agents such as etoposide, and truncated AIF (tAIF) is released from the mitochondria to the cytoplasm and translocated to the nucleus where it induces apoptosis. Although the serial events during tAIF-mediated apoptosis and the transition of AIF function have been widely studied from various perspectives, their underlying regulatory mechanisms and the factors involved are not fully understood. Here, we demonstrated that tAIF is a target of the covalent conjugation of the ubiquitin-like moiety ISG15 (referred to as ISGylation), which is mediated by the ISG15 E3 ligase HERC5. In addition, ISGylation increases the stability of tAIF protein as well as its K6-linked polyubiquitination. Moreover, we found that ISGylation increases the nuclear translocation of tAIF upon cytotoxic etoposide treatment, subsequently causing apoptotic cell death in human lung A549 carcinoma cells. Collectively, these results suggest that HERC5-mediated ISG15 conjugation is a key factor in the positive regulation of tAIF-mediated apoptosis, highlighting a novel role of posttranslational ISG15 modification as a switch that allows cells to live or die under the stress that triggers tAIF release.
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Affiliation(s)
- Seo Jeong Jeon
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Korea
| | - Kwang Chul Chung
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Korea.
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2
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Wischhof L, Scifo E, Ehninger D, Bano D. AIFM1 beyond cell death: An overview of this OXPHOS-inducing factor in mitochondrial diseases. EBioMedicine 2022; 83:104231. [PMID: 35994922 PMCID: PMC9420475 DOI: 10.1016/j.ebiom.2022.104231] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 08/01/2022] [Accepted: 08/02/2022] [Indexed: 11/17/2022] Open
Abstract
Apoptosis-inducing factor (AIF) is a mitochondrial intermembrane space flavoprotein with diverse functions in cellular physiology. In this regard, a large number of studies have elucidated AIF's participation to chromatin condensation during cell death in development, cancer, cardiovascular and brain disorders. However, the discovery of rare AIFM1 mutations in patients has shifted the interest of biomedical researchers towards AIF's contribution to pathogenic mechanisms underlying inherited AIFM1-linked metabolic diseases. The functional characterization of AIF binding partners has rapidly advanced our understanding of AIF biology within the mitochondria and beyond its widely reported role in cell death. At the present time, it is reasonable to assume that AIF contributes to cell survival by promoting biogenesis and maintenance of the mitochondrial oxidative phosphorylation (OXPHOS) system. With this review, we aim to outline the current knowledge around the vital role of AIF by primarily focusing on currently reported human diseases that have been linked to AIFM1 deficiency.
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Affiliation(s)
- Lena Wischhof
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Enzo Scifo
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Dan Ehninger
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Daniele Bano
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.
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3
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Yunos NM, Amin NDM, Jauri MH, Ling SK, Hassan NH, Sallehudin NJ. The In Vitro Anti-Cancer Activities and Mechanisms of Action of 9-Methoxycanthin-6-one from Eurycoma longifolia in Selected Cancer Cell Lines. Molecules 2022; 27:molecules27030585. [PMID: 35163852 PMCID: PMC8838174 DOI: 10.3390/molecules27030585] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/07/2022] [Accepted: 01/13/2022] [Indexed: 11/16/2022] Open
Abstract
An alkaloid compound from the hairy root culture of Eurycoma longifolia has been isolated and characterised as 9-methoxycanthin-6-one. The aims of these studies were to investigate the in vitro anti-cancer activities of 9-methoxycanthin-6-one against ovarian cancer (A2780, SKOV-3), breast cancer (MCF-7), colorectal cancer (HT29), skin cancer (A375) and cervical cancer (HeLa) cell lines by using a Sulphorhodamine B assay, and to evaluate the mechanisms of action of 9-methoxycanthin-6-one via the Hoechst 33342 assay and proteomics approach. The results had shown that 9-methoxycanthin-6-one gave IC50 values of 4.04 ± 0.36 µM, 5.80 ± 0.40 µM, 15.09 ± 0.99 µM, 3.79 ± 0.069 µM, 5.71 ± 0.20 µM and 4.30 ± 0.27 µM when tested in A2780, SKOV-3, MCF-7, HT-29, A375 and HeLa cell lines, respectively. It was found that 9-methoxycanthin-6-one induced apoptosis in a concentration dependent manner when analysed via the Hoechst 33342 assay. 9-methoxycanthine-6-one were found to affect the expressions of apoptotic-related proteins, that were proteins pyruvate kinase (PKM), annexin A2 (ANXA2), galectin 3 (LGAL3), heterogeneous nuclear ribonucleoprotein A1 (HNRNP1A1), peroxiredoxin 3 (PRDX3), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from the differential analysis of 2-DE profiles between treated and non-treated 9-methoxycanthine-6-one. Proteins such as acetyl-CoA acyltransferase 2 (ACAA2), aldehyde dehydrogenase 1 (ALDH1A1), capping protein (CAPG), eukaryotic translation elongation factor 1 (EEF1A1), malate dehydrogenase 2 (MDH2), purine nucleoside phosphorylase (PNP), and triosephosphate isomerase 1 (TPI1) were also identified to be associated with A2780 cell death induced by 9-methoxycanthine-6-one. These findings may provide a new insight on the mechanisms of action of 9-methoxycanthin-6-one in exerting its anti-cancer effects in vitro.
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Affiliation(s)
- Nurhanan Murni Yunos
- Bioactivity Programme, Natural Products Division, Forest Research Institute Malaysia, Kepong 52109, Malaysia; (N.D.M.A.); (N.J.S.)
- Correspondence: ; Tel.: +60-3627-97659
| | - Nor Datiakma Mat Amin
- Bioactivity Programme, Natural Products Division, Forest Research Institute Malaysia, Kepong 52109, Malaysia; (N.D.M.A.); (N.J.S.)
| | - Muhammad Haffiz Jauri
- Phytochemistry Programme, Natural Products Division, Forest Research Institute Malaysia, Kepong 52109, Malaysia; (M.H.J.); (S.K.L.)
| | - Sui Kiong Ling
- Phytochemistry Programme, Natural Products Division, Forest Research Institute Malaysia, Kepong 52109, Malaysia; (M.H.J.); (S.K.L.)
| | - Nor Hasnida Hassan
- Biotechnology Programme, Forestry Biotechnology Division, Forest Research Institute Malaysia, Kepong 52109, Malaysia;
| | - Nor Jannah Sallehudin
- Bioactivity Programme, Natural Products Division, Forest Research Institute Malaysia, Kepong 52109, Malaysia; (N.D.M.A.); (N.J.S.)
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4
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Luo Q, Wu X, Zhao P, Nan Y, Chang W, Zhu X, Su D, Liu Z. OTUD1 Activates Caspase-Independent and Caspase-Dependent Apoptosis by Promoting AIF Nuclear Translocation and MCL1 Degradation. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2002874. [PMID: 33898171 PMCID: PMC8061361 DOI: 10.1002/advs.202002874] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 12/29/2020] [Indexed: 05/25/2023]
Abstract
Apoptosis-inducing factor (AIF) plays a dual role in regulating cell survival and apoptosis, acting as a prosurvival factor in mitochondria via its NADH oxidoreductase activity and activating the caspase-independent apoptotic pathway (i.e., parthanatos) after nuclear translocation. However, whether one factor conjunctively controls the separated functions of AIF is not clear. Here, it is shown that OTU deubiquitinase 1 (OTUD1) acts as a link between the two functions of AIF via deubiquitination events. Deubiquitination of AIF at K244 disrupts the normal mitochondrial structure and compromises oxidative phosphorylation, and deubiquitination of AIF at K255 enhances its DNA-binding ability to promote parthanatos. Moreover, OTUD1 stabilizes DDB1 and CUL4 associated factor 10 (DCAF10) and recruits the cullin 4A (CUL4A)-damage specific DNA binding protein 1 (DDB1) complex to promote myeloid cell leukemia sequence 1 (MCL1) degradation, thereby activating caspase-dependent apoptotic signaling. Collectively, these results reveal the central role of OTUD1 in activating both caspase-independent and caspase-dependent apoptotic signaling and propose decreased OTUD1 expression as a key event promoting chemoresistance in esophageal squamous cell carcinoma.
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Affiliation(s)
- Qingyu Luo
- State Key Laboratory of Molecular OncologyNational Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100021China
| | - Xiaowei Wu
- State Key Laboratory of Molecular OncologyNational Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100021China
| | - Pengfei Zhao
- State Key Laboratory of Molecular OncologyNational Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100021China
| | - Yabing Nan
- State Key Laboratory of Molecular OncologyNational Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100021China
| | - Wan Chang
- State Key Laboratory of Molecular OncologyNational Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100021China
| | - Xiaolin Zhu
- State Key Laboratory of Molecular OncologyNational Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100021China
| | - Dan Su
- Department of PathologyZhejiang Cancer HospitalZhejiang310022China
| | - Zhihua Liu
- State Key Laboratory of Molecular OncologyNational Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100021China
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5
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The human papillomavirus E6 protein targets apoptosis-inducing factor (AIF) for degradation. Sci Rep 2020; 10:14195. [PMID: 32848167 PMCID: PMC7450093 DOI: 10.1038/s41598-020-71134-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 08/07/2020] [Indexed: 12/13/2022] Open
Abstract
Oncoprotein E6 of high-risk human papillomavirus (HPV) plays a critical role in inducing cell immortalization and malignancy. E6 downregulates caspase-dependent pathway through the degradation of p53. However, the effect of HPV E6 on other pathways is still under investigation. In the present study, we found that HPV E6 directly binds to all three forms (precursor, mature, and apoptotic) of apoptosis-inducing factor (AIF) and co-localizes with apoptotic AIF. This binding induced MG132-sensitive reduction of AIF expression in the presence of E6 derived from HPV16 (16E6), a cancer-causing type of HPV. Conversely, E6 derived from a non-cancer-causing type of HPV, HPV6 (6E6), did not reduce the levels of AIF despite its interaction with AIF. Flow cytometric analysis revealed that 16E6, but not 6E6, suppressed apoptotic AIF-induced chromatin degradation (an indicator of caspase-independent apoptosis) and staurosporine (STS, a protein kinase inhibitor)-induced apoptosis. AIF knockdown reduced STS-induced apoptosis in both of 16E6-expressing and 6E6-expressing cells; however, the reduction in 16E6-expressing cells was lower than that in 6E6-expressing cells. These findings indicate that 16E6, but not 6E6, blocks AIF-mediated apoptosis, and that AIF may represent a novel therapeutic target for HPV-induced cervical cancer.
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6
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The poly-ADP ribose polymerase-1/apoptosis-inducing factor pathway may help mediate the protective effect of electroacupuncture on early brain injury after subarachnoid hemorrhage. Neuroreport 2020; 31:605-612. [PMID: 32301816 DOI: 10.1097/wnr.0000000000001445] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Subarachnoid hemorrhage (SAH) is a clinically common, acute, critical cerebrovascular disease associated with high mortality. Here, we investigated the effects of electroacupuncture on early brain injury after SAH. We successfully established a Sprague-Dawley rat model of the SAH model, and randomly divided the rats into four groups: sham-operated group, SAH group, positive control group, and electroacupuncture group. Electroacupuncture effectively decreased the number of transferase UTP nick end labeling-positive cells and extent of DNA fragmentation compared with the control, indicating a decrease in apoptosis. Moreover, electroacupuncture decreased the expression of proteins involved in the poly-ADP ribose polymerase-1/apoptosis-inducing factor (PARP-1/AIF) pathway in vivo, and the difference was statistically significant (P < 0.05). Treatment with electroacupuncture resulted in a significant improvement in neurological function. It inhibited the increase in blood-brain barrier permeability by regulating the protein expression of matrix metalloproteinase-9, occludin, and claudin-5. Additionally, electroacupuncture limited the development of cerebral edema and microglial activation in early brain injury after SAH. In conclusion, electroacupuncture can ameliorate early brain injury after SAH, and this may occur via inhibition of the PARP-1/AIF pathway.
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7
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IAP-Mediated Protein Ubiquitination in Regulating Cell Signaling. Cells 2020; 9:cells9051118. [PMID: 32365919 PMCID: PMC7290580 DOI: 10.3390/cells9051118] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 04/27/2020] [Accepted: 04/28/2020] [Indexed: 12/12/2022] Open
Abstract
Over the last decade, the E3-ubiquitine ligases from IAP (Inhibitor of Apoptosis) family have emerged as potent regulators of immune response. In immune cells, they control signaling pathways driving differentiation and inflammation in response to stimulation of tumor necrosis factor receptor (TNFR) family, pattern-recognition receptors (PRRs), and some cytokine receptors. They are able to control the activity, the cellular fate, or the stability of actors of signaling pathways, acting at different levels from components of receptor-associated multiprotein complexes to signaling effectors and transcription factors, as well as cytoskeleton regulators. Much less is known about ubiquitination substrates involved in non-immune signaling pathways. This review aimed to present IAP ubiquitination substrates and the role of IAP-mediated ubiquitination in regulating signaling pathways.
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8
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XIAP as a Target of New Small Organic Natural Molecules Inducing Human Cancer Cell Death. Cancers (Basel) 2019; 11:cancers11091336. [PMID: 31505859 PMCID: PMC6770071 DOI: 10.3390/cancers11091336] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 09/04/2019] [Indexed: 12/11/2022] Open
Abstract
X-linked inhibitor of apoptosis protein (XIAP) is an emerging crucial therapeutic target in cancer. We report on the discovery and characterisation of small organic molecules from Piper genus plants exhibiting XIAP antagonism, namely erioquinol, a quinol substituted in the 4-position with an alkenyl group and the alkenylphenols eriopodols A–C. Another isolated compound was originally identified as gibbilimbol B. Erioquinol was the most potent inhibitor of human cancer cell viability when compared with gibbilimbol B and eriopodol A was listed as intermediate. Gibbilimbol B and eriopodol A induced apoptosis through mitochondrial permeabilisation and caspase activation while erioquinol acted on cell fate via caspase-independent/non-apoptotic mechanisms, likely involving mitochondrial dysfunctions and aberrant generation of reactive oxygen species. In silico modelling and molecular approaches suggested that all molecules inhibit XIAP by binding to XIAP-baculoviral IAP repeat domain. This demonstrates a novel aspect of XIAP as a key determinant of tumour control, at the molecular crossroad of caspase-dependent/independent cell death pathway and indicates molecular aspects to develop tumour-effective XIAP antagonists.
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9
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Nalawansha DA, Zhang Y, Herath K, Pflum MKH. HDAC1 Substrate Profiling Using Proteomics-Based Substrate Trapping. ACS Chem Biol 2018; 13:3315-3324. [PMID: 30421914 PMCID: PMC6563814 DOI: 10.1021/acschembio.8b00737] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Histone deacetylase (HDAC) proteins are overexpressed in multiple diseases, including cancer, and have emerged as anticancer drug targets. HDAC proteins regulate cellular processes, such as the cell cycle, apoptosis, and cell proliferation, by deacetylating histone and non-histone substrates. Although a plethora of acetylated proteins have been identified using large-scale proteomic approaches, the HDAC proteins responsible for their dynamic deacetylation have been poorly studied. For example, few substrates of HDAC1 have been identified, which is mainly due to the scarcity of substrate identification tools. We recently developed a mutant trapping strategy to identify novel substrates of HDAC1. Herein, we introduce an improved version of the trapping method that uses mass spectrometry (MS)-based proteomics to identify multiple substrates simultaneously. Among the substrate hits, CDK1, AIFM1, MSH6, and RuvB-like 1 were identified as likely HDAC1 substrates. These newly discovered HDAC1 substrates are involved in various biological processes, suggesting novel functions of HDAC1 apart from epigenetics. Substrate trapping combined with MS-based proteomics provides an efficient approach to HDAC1 substrate identification and contributes to the full characterization of HDAC function in normal and disease states.
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Affiliation(s)
| | - Yuchen Zhang
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI 48202
| | - Kavinda Herath
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI 48202
| | - Mary Kay H. Pflum
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI 48202
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10
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Scott AJ, Walker SA, Krank JJ, Wilkinson AS, Johnson KM, Lewis EM, Wilkinson JC. AIF promotes a JNK1-mediated cadherin switch independently of respiratory chain stabilization. J Biol Chem 2018; 293:14707-14722. [PMID: 30093403 DOI: 10.1074/jbc.ra118.004022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/26/2018] [Indexed: 12/18/2022] Open
Abstract
Apoptosis-inducing factor (AIF) is a mitochondrial flavoprotein occasionally involved in cell death that primarily regulates mitochondrial energy metabolism under normal cellular conditions. AIF catalyzes the oxidation of NADH in vitro, yet the significance of this redox activity in cells remains unclear. Here, we show that through its enzymatic activity AIF is a critical factor for oxidative stress-induced activation of the mitogen-activated protein kinases JNK1 (c-Jun N-terminal kinase), p38, and ERK (extracellular signal-regulated kinase). AIF-dependent JNK1 signaling culminates in the cadherin switch, and genetic reversal of this switch leads to apoptosis when AIF is suppressed. Notably, this widespread ability of AIF to promote JNK signaling can be uncoupled from its more limited role in respiratory chain stabilization. Thus, AIF is a transmitter of extra-mitochondrial signaling cues with important implications for human development and disease.
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Affiliation(s)
- Andrew J Scott
- From the Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108 and
| | - Sierra A Walker
- From the Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108 and
| | - Joshua J Krank
- From the Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108 and
| | - Amanda S Wilkinson
- From the Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108 and
| | - Kaitlyn M Johnson
- From the Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108 and
| | - Eric M Lewis
- the Department of Chemistry, Mathematics and Physics, Clarion University of Pennsylvania, Clarion, Pennsylvania 16214
| | - John C Wilkinson
- From the Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108 and
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11
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Wiedenhoft H, Hayashi L, Coffin AB. PI3K and Inhibitor of Apoptosis Proteins Modulate Gentamicin- Induced Hair Cell Death in the Zebrafish Lateral Line. Front Cell Neurosci 2017; 11:326. [PMID: 29093665 PMCID: PMC5651234 DOI: 10.3389/fncel.2017.00326] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 10/03/2017] [Indexed: 12/16/2022] Open
Abstract
Inner ear hair cell death leads to sensorineural hearing loss and can be a direct consequence of aminoglycoside antibiotic treatment. Aminoglycosides such as gentamicin are effective therapy for serious Gram-negative bacterial infections such as some forms of meningitis, pneumonia, and sepsis. Aminoglycosides enter hair cells through mechanotransduction channels at the apical end of hair bundles and initiate intrinsic cell death cascades, but the precise cell signaling that leads to hair cell death is incompletely understood. Here, we examine the cell death pathways involved in aminoglycoside damage using the zebrafish (Danio rerio). The zebrafish lateral line contains hair cell-bearing organs called neuromasts that are homologous to hair cells of the mammalian inner ear and represents an excellent model to study ototoxicity. Based on previous research demonstrating a role for p53, Bcl2 signaling, autophagy, and proteasomal degradation in aminoglycoside-damaged hair cells, we used the Cytoscape GeneMANIA Database to identify additional proteins that might play a role in neomycin or gentamicin ototoxicity. Our bioinformatics analysis identified the pro-survival proteins phosphoinositide-dependent kinase-1 (PDK1) and X-linked inhibitor of apoptosis protein (Xiap) as potential mediators of gentamicin-induced hair cell damage. Pharmacological inhibition of PDK1 or its downstream mediator protein kinase C facilitated gentamicin toxicity, as did Xiap mutation, suggesting that both PI3K and endogenous Xiap confer protection. Surprisingly, aminoglycoside-induced hair cell death was highly attenuated in wild type Tupfel long-fin (TL fish; the background strain for the Xiap mutant line) compared to wild type ∗AB zebrafish. Pharmacologic manipulation of p53 suggested that the strain difference might result from decreased p53 in TL hair cells, allowing for increased hair cell survival. Overall, our studies identified additional steps in the cell death cascade triggered by aminoglycoside damage, suggesting possible drug targets to combat hearing loss resulting from aminoglycoside exposure.
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Affiliation(s)
- Heather Wiedenhoft
- College of Arts and Sciences, Washington State University, Vancouver, WA, United States
| | - Lauren Hayashi
- Knight Cancer Institute, Oregon Health & Science University, Portland, OR, United States
| | - Allison B Coffin
- College of Arts and Sciences, Washington State University, Vancouver, WA, United States.,Department of Integrative Physiology and Neuroscience, Washington State University, Vancouver, WA, United States
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12
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Brosey CA, Ho C, Long WZ, Singh S, Burnett K, Hura GL, Nix JC, Bowman GR, Ellenberger T, Tainer JA. Defining NADH-Driven Allostery Regulating Apoptosis-Inducing Factor. Structure 2016; 24:2067-2079. [PMID: 27818101 DOI: 10.1016/j.str.2016.09.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 09/08/2016] [Accepted: 10/05/2016] [Indexed: 01/07/2023]
Abstract
Apoptosis-inducing factor (AIF) is critical for mitochondrial respiratory complex biogenesis and for mediating necroptotic parthanatos; these functions are seemingly regulated by enigmatic allosteric switching driven by NADH charge-transfer complex (CTC) formation. Here, we define molecular pathways linking AIF's active site to allosteric switching regions by characterizing dimer-permissive mutants using small-angle X-ray scattering (SAXS) and crystallography and by probing AIF-CTC communication networks using molecular dynamics simulations. Collective results identify two pathways propagating allostery from the CTC active site: (1) active-site H454 links to S480 of AIF's central β-strand to modulate a hydrophobic border at the dimerization interface, and (2) an interaction network links AIF's FAD cofactor, central β-strand, and Cβ-clasp whereby R529 reorientation initiates C-loop release during CTC formation. This knowledge of AIF allostery and its flavoswitch mechanism provides a foundation for biologically understanding and biomedically controlling its participation in mitochondrial homeostasis and cell death.
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Affiliation(s)
- Chris A Brosey
- Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA; Molecular and Cellular Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
| | - Chris Ho
- Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Winnie Z Long
- Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Sukrit Singh
- Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Kathryn Burnett
- MBIB Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Greg L Hura
- MBIB Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | - Jay C Nix
- Molecular Biology Consortium, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Gregory R Bowman
- Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Tom Ellenberger
- Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - John A Tainer
- MBIB Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Molecular and Cellular Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
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13
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Lenhausen AM, Wilkinson AS, Lewis EM, Dailey KM, Scott AJ, Khan S, Wilkinson JC. Apoptosis Inducing Factor Binding Protein PGAM5 Triggers Mitophagic Cell Death That Is Inhibited by the Ubiquitin Ligase Activity of X-Linked Inhibitor of Apoptosis. Biochemistry 2016; 55:3285-302. [PMID: 27218139 DOI: 10.1021/acs.biochem.6b00306] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Apoptosis inducing factor (AIF) plays a well-defined role in controlling cell death but is also a critical factor for maintaining mitochondrial energy homeostasis; how these dueling activities are balanced has remained largely elusive. To identify new AIF binding partners that may define the continuum of AIF cellular regulation, a biochemical screen was performed that identified the mitochondrial phosphoglycerate mutase 5 (PGAM5) as an AIF associated factor. AIF binds both the short and long isoforms of PGAM5 and can reduce the ability of PGAM5 to control antioxidant responses. Transient overexpression of either PGAM5 isoform triggers caspase activation and cell death, and while AIF could reduce this caspase activation neither AIF expression nor caspase activity is required for PGAM5-mediated death. PGAM5 toxicity morphologically and biochemically resembles mitophagic cell death and is inhibited by the AIF binding protein X-linked inhibitor of apoptosis (XIAP) in a manner that depends on the ubiquitin ligase activity of XIAP. The phosphatase activity of PGAM5 was not required for cell death, and comparison of phosphatase activity between short and long PGAM5 isoforms suggested that only the long isoform is catalytically competent. This property correlated with an increased ability of PGAM5L to form dimers and/or higher order oligomers in intact cells compared to PGAM5S. Overall this study identifies an AIF/PGAM5/XIAP axis that can regulate PGAM5 activities related to the antioxidant response and mitophagy.
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Affiliation(s)
- Audrey M Lenhausen
- Department of Biochemistry, Wake Forest School of Medicine , Winston-Salem, North Carolina 27157, United States
| | - Amanda S Wilkinson
- Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108, United States
| | - Eric M Lewis
- Department of Biochemistry, Wake Forest School of Medicine , Winston-Salem, North Carolina 27157, United States
| | - Kaitlin M Dailey
- Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108, United States
| | - Andrew J Scott
- Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108, United States
| | - Shahzeb Khan
- Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108, United States
| | - John C Wilkinson
- Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108, United States
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14
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Sarin H. Conserved molecular mechanisms underlying the effects of small molecule xenobiotic chemotherapeutics on cells. Mol Clin Oncol 2015; 4:326-368. [PMID: 26998284 DOI: 10.3892/mco.2015.714] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 12/08/2015] [Indexed: 12/14/2022] Open
Abstract
For proper determination of the apoptotic potential of chemoxenobiotics in synergism, it is important to understand the modes, levels and character of interactions of chemoxenobiotics with cells in the context of predicted conserved biophysical properties. Chemoxenobiotic structures are studied with respect to atom distribution over molecular space, the predicted overall octanol-to-water partition coefficient (Log OWPC; unitless) and molecular size viz a viz van der Waals diameter (vdWD). The Log OWPC-to-vdWD (nm-1 ) parameter is determined, and where applicable, hydrophilic interacting moiety/core-to-vdWD (nm-1 ) and lipophilic incorporating hydrophobic moiety/core-to-vdWD (nm-1 ) parameters of their part-structures are determined. The cellular and sub-cellular level interactions of the spectrum of xenobiotic chemotherapies have been characterized, for which a classification system has been developed based on predicted conserved biophysical properties with respect to the mode of chemotherapeutic effect. The findings of this study are applicable towards improving the effectiveness of existing combination chemotherapy regimens and the predictive accuracy of personalized cancer treatment algorithms as well as towards the selection of appropriate novel xenobiotics with the potential to be potent chemotherapeutics for dendrimer nanoparticle-based effective transvascular delivery.
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Affiliation(s)
- Hemant Sarin
- Freelance Investigator in Translational Science and Medicine, Charleston, WV 25314, USA
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15
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Zhao X, Jiang K, Liang B, Huang X. Anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through NF-κB/p53-apoptosis signaling pathway. Oncol Rep 2015; 35:669-75. [PMID: 26718026 PMCID: PMC4689487 DOI: 10.3892/or.2015.4455] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 09/23/2015] [Indexed: 12/29/2022] Open
Abstract
Xanthohumol may prevent and cure diabetes and atherosis, have oxidation resistance and antiviral function as well as anticancer effect preventing cancer cell metastasis. We investigate whether the anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through NF-κB/p53-apoptosis signaling pathway. Human liver cancer HepG2 cell were treated with 10, 20, 30 and 40 µM xanthohumol for 48 h. The present study showed that the anticancer effect of xanthohumol was effective in inhibiting proliferation and inducing apoptosis of human liver cancer HepG2 cells. Furthermore, the caspase-3 activity of human liver cancer HepG2 cells was increased by xanthohumol. In addition, 48-h treatment with xanthohumol suppressed NF-κB expression and promoted p53, cleaved PARP, AIF and cytochrome c expression and downregulated XIAP and Bcl-2/Bax expression in human liver cancer HepG2 cells. Therefore, the anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through the NF-κB/p53-apoptosis signaling pathway.
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Affiliation(s)
- Xiangqian Zhao
- Hospital and Institute of Hepatobiliary Surgery, Chinese PLA General Hospital, Beijing 100853, P.R. China
| | - Kai Jiang
- Hospital and Institute of Hepatobiliary Surgery, Chinese PLA General Hospital, Beijing 100853, P.R. China
| | - Bin Liang
- Hospital and Institute of Hepatobiliary Surgery, Chinese PLA General Hospital, Beijing 100853, P.R. China
| | - Xiaoqiang Huang
- Hospital and Institute of Hepatobiliary Surgery, Chinese PLA General Hospital, Beijing 100853, P.R. China
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16
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Chen YS, Qiu XB. Ubiquitin at the crossroad of cell death and survival. CHINESE JOURNAL OF CANCER 2013; 32:640-7. [PMID: 23816559 PMCID: PMC3870847 DOI: 10.5732/cjc.012.10283] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Revised: 02/20/2013] [Accepted: 03/15/2013] [Indexed: 12/19/2022]
Abstract
Ubiquitination is crucial for cellular processes, such as protein degradation, apoptosis, autophagy, and cell cycle progression. Dysregulation of the ubiquitination network accounts for the development of numerous diseases, including cancer. Thus, targeting ubiquitination is a promising strategy in cancer therapy. Both apoptosis and autophagy are involved in tumorigenesis and response to cancer therapy. Although both are categorized as types of cell death, autophagy is generally considered to have protective functions, including protecting cells from apoptosis under certain cellular stress conditions. This review highlights recent advances in understanding the regulation of apoptosis and autophagy by ubiquitination.
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Affiliation(s)
- Yu-Shan Chen
- Key Laboratory of Cell Proliferation and Regulation Biology, Ministry of Education, and College of Life Sciences, Beijing Normal University, Beijing 100875, P. R. China.
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17
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Farrand L, Kim JY, Byun S, Im-aram A, Lee J, Suh JY, Lee KW, Lee HJ, Tsang BK. The diarylheptanoid hirsutenone sensitizes chemoresistant ovarian cancer cells to cisplatin via modulation of apoptosis-inducing factor and X-linked inhibitor of apoptosis. J Biol Chem 2013; 289:1723-31. [PMID: 24247248 PMCID: PMC3894349 DOI: 10.1074/jbc.m113.513879] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Cisplatin (CDDP) and its derivatives are considered first-line treatments for ovarian cancer (OVCA). However, despite initial results that often appear promising, in most cases patients will return with recurrent disease that fails to respond to further chemotherapy. We assayed a number of food phytochemicals with reported PI3K inhibitory ability to identify candidates that can influence CDDP treatment outcomes in chemoresistant OVCA cell lines. A direct comparison revealed that the diarylheptanoid hirsutenone from the tree bark of Alnus hirsuta var. sibirica was superior at inducing CDDP sensitivity in a number of chemoresistant cancer cell lines. Whereas hirsutenone treatment activated p53, its modest efficacy in p53-mutant and -null cell lines suggested the existence of a p53-independent mode of action. Further investigation revealed that hirsutenone causes CDDP-dependent apoptosis in chemoresistant cells by ubiquitin-proteasome-dependent X-linked inhibitor of apoptosis degradation and by enhancing the translocation of apoptosis-inducing factor from the mitochondria to the nucleus. This was found to be, at least in part, under the influence of upstream Akt activity, linking hirsutenone-dependent PI3K inhibition with downstream effects on apoptosis-inducing factor, X-linked inhibitor of apoptosis, and apoptosis. Our findings provide rationale for further investigation of the effects of hirsutenone on chemoresistant OVCA in clinical studies.
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Affiliation(s)
- Lee Farrand
- From the World Class University Major in Biomodulation, Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, Seoul National University, Republic of Korea
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18
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Orebaugh CD, Fye JM, Harvey S, Hollis T, Wilkinson JC, Perrino FW. The TREX1 C-terminal region controls cellular localization through ubiquitination. J Biol Chem 2013; 288:28881-92. [PMID: 23979357 DOI: 10.1074/jbc.m113.503391] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
TREX1 is an autonomous 3'-exonuclease that degrades DNA to prevent inappropriate immune activation. The TREX1 protein is composed of 314 amino acids; the N-terminal 242 amino acids contain the catalytic domain, and the C-terminal region (CTR) localizes TREX1 to the cytosolic compartment. In this study, we show that TREX1 modification by ubiquitination is controlled by a highly conserved sequence in the CTR to affect cellular localization. Transfection of TREX1 deletion constructs into human cells demonstrated that this sequence is required for ubiquitination at multiple lysine residues through a "non-canonical" ubiquitin linkage. A proteomic approach identified ubiquilin 1 as a TREX1 CTR-interacting protein, and this interaction was verified in vitro and in vivo. Cotransfection studies indicated that ubiquilin 1 localizes TREX1 to cytosolic punctate structures dependent upon the TREX1 CTR and lysines within the TREX1 catalytic core. Several TREX1 mutants linked to the autoimmune diseases Aicardi-Goutières syndrome and systemic lupus erythematosus that exhibit full catalytic function were tested for altered ubiquitin modification and cellular localization. Our data show that these catalytically competent disease-causing TREX1 mutants exhibit differential levels of ubiquitination relative to WT TREX1, suggesting a novel mechanism of dysfunction. Furthermore, these differentially ubiquitinated disease-causing mutants also exhibit altered ubiquilin 1 co-localization. Thus, TREX1 post-translational modification indicates an additional mechanism by which mutations disrupt TREX1 biology, leading to human autoimmune disease.
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Affiliation(s)
- Clinton D Orebaugh
- From the Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, North Carolina 27157
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19
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Feng X, Koh DW. Roles of poly(ADP-ribose) glycohydrolase in DNA damage and apoptosis. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 304:227-81. [PMID: 23809438 DOI: 10.1016/b978-0-12-407696-9.00005-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Poly(ADP-ribose) glycohydrolase (PARG) is the primary enzyme that catalyzes the hydrolysis of poly(ADP-ribose) (PAR), an essential biopolymer that is synthesized by poly(ADP-ribose) polymerases (PARPs) in the cell. By regulating the hydrolytic arm of poly(ADP-ribosyl)ation, PARG participates in a number of biological processes, including the repair of DNA damage, chromatin dynamics, transcriptional regulation, and cell death. Collectively, the research investigating the roles of PARG in the cell has identified the importance of PARG and its value as a therapeutic target. However, the biological role of PARG remains less understood than the role of PAR synthesis by the PARPs. Further complicating the study of PARG is the existence of multiple PARG isoforms in the cell, the lack of optimal PARG inhibitors, and the lack of viable PARG-null animals. This review will present our current knowledge of PARG, with a focus on its roles in DNA-damage repair and cell death.
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Affiliation(s)
- Xiaoxing Feng
- Department of Pharmaceutical Sciences, College of Pharmacy, Washington State University, Pullman, Washington, USA
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20
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Lewis EM, Wilkinson AS, Jackson JS, Mehra R, Varambally S, Chinnaiyan AM, Wilkinson JC. The enzymatic activity of apoptosis-inducing factor supports energy metabolism benefiting the growth and invasiveness of advanced prostate cancer cells. J Biol Chem 2012; 287:43862-75. [PMID: 23118229 DOI: 10.1074/jbc.m112.407650] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Apoptosis-inducing factor (AIF) promotes cell death yet also controls mitochondrial homeostasis and energy metabolism. It is unclear how these activities are coordinated, and the impact of AIF upon human disease, in particular cancer, is not well documented. In this study we have explored the contribution of AIF to the progression of prostate cancer. Analysis of archival gene expression data demonstrated that AIF transcript levels are elevated in human prostate cancer, and we found that AIF protein is increased in prostate tumors. Suppression of AIF expression in the prostate cancer cell lines LNCaP, DU145, and PC3 demonstrated that AIF does not contribute to cell toxicity via a variety of chemical death triggers, and growth under nutrient-rich conditions is largely unaffected by AIF ablation. However, under growth stress conditions, AIF depletion from DU145 and PC3 cell lines led to significant reductions in cell survival and growth that were not observed in LNCaP cells. Moreover AIF-deficient PC3 cells exhibited substantial reduction of tumorigenic growth in vivo. This reduced survival correlated with decreased expression of mitochondrial complex I protein subunits and concomitant changes in glucose metabolism. Finally, restoration of AIF-deficient PC3 cells with AIF variants demonstrated that the enzymatic activity of AIF is required for aggressive growth. Overall these studies show that AIF is an important factor for advanced prostate cancer cells and that through control of energy metabolism and redox balance, the enzymatic activity of AIF is critical for this support.
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Affiliation(s)
- Eric M Lewis
- Department of Biochemistry, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA
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21
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Bowlby SC, Thomas MJ, D’Agostino RB, Kridel SJ. Nicotinamide phosphoribosyl transferase (Nampt) is required for de novo lipogenesis in tumor cells. PLoS One 2012; 7:e40195. [PMID: 22768255 PMCID: PMC3387004 DOI: 10.1371/journal.pone.0040195] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Accepted: 06/02/2012] [Indexed: 11/18/2022] Open
Abstract
Tumor cells have increased metabolic requirements to maintain rapid growth. In particular, a highly lipogenic phenotype is a hallmark of many tumor types, including prostate. Cancer cells also have increased turnover of nicotinamide adenine dinucleotide (NAD+), a coenzyme involved in multiple metabolic pathways. However, a specific role for NAD+ in tumor cell lipogenesis has yet to be described. Our studies demonstrate a novel role for the NAD+-biosynthetic enzyme Nicotinamide phosphoribosyltransferase (Nampt) in maintaining de novo lipogenesis in prostate cancer (PCa) cells. Inhibition of Nampt reduces fatty acid and phospholipid synthesis. In particular, short chain saturated fatty acids and the phosphatidylcholine (PC) lipids into which these fatty acids are incorporated were specifically reduced by Nampt inhibition. Nampt blockade resulted in reduced ATP levels and concomitant activation of AMP-activated protein kinase (AMPK) and phosphorylation of acetyl-CoA carboxylase (ACC). In spite of this, pharmacological inhibition of AMPK was not sufficient to fully restore fatty acid synthesis. Rather, Nampt blockade also induced protein hyperacetylation in PC-3, DU145, and LNCaP cells, which correlated with the observed decreases in lipid synthesis. Moreover, the sirtuin inhibitor Sirtinol, and the simultaneous knockdown of SIRT1 and SIRT3, phenocopied the effects of Nampt inhibition on fatty acid synthesis. Altogether, these data reveal a novel role for Nampt in the regulation of de novo lipogenesis through the modulation of sirtuin activity in PCa cells.
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Affiliation(s)
- Sarah C. Bowlby
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Michael J. Thomas
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
- Comprehensive Cancer Center, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Ralph B. D’Agostino
- Department of Biostatistical Sciences, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
- Comprehensive Cancer Center, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - Steven J. Kridel
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
- Comprehensive Cancer Center, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
- * E-mail:
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