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Xie JJ, Xie YM, Chen B, Pan F, Guo JC, Zhao Q, Shen JH, Wu ZY, Wu JY, Xu LY, Li EM. ATF3 functions as a novel tumor suppressor with prognostic significance in esophageal squamous cell carcinoma. Oncotarget 2015; 5:8569-82. [PMID: 25149542 PMCID: PMC4226705 DOI: 10.18632/oncotarget.2322] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
ATF3 was a transcription factor involved in the progression of certain cancers. Here, we sought to explore the expression and biological function of ATF3 in esophageal squamous cell carcinomas (ESCC). The prognostic significance of ATF3 expression was evaluated in 150 ESCC samples and 21 normal squamous cell epithelium tissues. Results showed that ATF3 was down-regulated in ESCC lesions compared with paired non-cancerous tissues and low tumorous ATF3 expression significantly correlated with shorter overall survival (OS) and disease-free survival (DFS). Cox regression analysis confirmed that ATF3 expression was an independent prognostic factor. Experimentally, forced expression of ATF3 led to decreased growth and invasion properties of ESCC cells in vitro and in vivo, whereas knockdown of ATF3 did the opposite. Furthermore, ATF3 upregulated the expression of MDM2 by increasing the nuclear translocation of P53 and formed an ATF3/MDM2/MMP-2 complex that facilitated MMP-2 degradation, which subsequently led to inhibition of cell invasion. Finally, we showed that Cisplatin could restrain the invasion of ESCC cells by inducing the expression of ATF3 via P53 signaling. Combined, our findings highlight a suppressed role for ATF3 in ESCC and targeting ATF3 might be a potential therapeutic strategy.
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Affiliation(s)
- Jian-Jun Xie
- Key Laboratory of Molecular Biology in High Cancer Incidence Coastal Chaoshan Area of Guangdong Higher Education Institutes, Medical College of Shantou University, Shantou 515041, P. R. China. Department of Biochemistry and Molecular Biology, Medical College of Shantou University, Shantou 515041, P. R. China
| | - Yang-Min Xie
- Key Laboratory of Molecular Biology in High Cancer Incidence Coastal Chaoshan Area of Guangdong Higher Education Institutes, Medical College of Shantou University, Shantou 515041, P. R. China. Department of Experimental Animal Center, Medical College of Shantou University, Shantou 515041, P. R. China
| | - Bo Chen
- Key Laboratory of Molecular Biology in High Cancer Incidence Coastal Chaoshan Area of Guangdong Higher Education Institutes, Medical College of Shantou University, Shantou 515041, P. R. China. Institute of Oncologic Pathology, Medical College of Shantou University, Shantou 515041, P. R. China
| | - Feng Pan
- Key Laboratory of Molecular Biology in High Cancer Incidence Coastal Chaoshan Area of Guangdong Higher Education Institutes, Medical College of Shantou University, Shantou 515041, P. R. China. Department of Biochemistry and Molecular Biology, Medical College of Shantou University, Shantou 515041, P. R. China
| | - Jin-Cheng Guo
- Key Laboratory of Molecular Biology in High Cancer Incidence Coastal Chaoshan Area of Guangdong Higher Education Institutes, Medical College of Shantou University, Shantou 515041, P. R. China. Department of Biochemistry and Molecular Biology, Medical College of Shantou University, Shantou 515041, P. R. China
| | - Qing Zhao
- Key Laboratory of Molecular Biology in High Cancer Incidence Coastal Chaoshan Area of Guangdong Higher Education Institutes, Medical College of Shantou University, Shantou 515041, P. R. China. Institute of Oncologic Pathology, Medical College of Shantou University, Shantou 515041, P. R. China
| | - Jin-Hui Shen
- Department of Pathology, Shantou Central Hospital, Affiliated Shantou Hospital of Sun Yat-Sen University, Shantou 515041, P. R. China
| | - Zhi-Yong Wu
- Key Laboratory of Molecular Biology in High Cancer Incidence Coastal Chaoshan Area of Guangdong Higher Education Institutes, Medical College of Shantou University, Shantou 515041, P. R. China. Department of Oncologic Surgery, Shantou Central Hospital, Affiliated Shantou Hospital of Sun Yat-Sen University, Shantou 515041, P. R. China
| | - Jian-Yi Wu
- Key Laboratory of Molecular Biology in High Cancer Incidence Coastal Chaoshan Area of Guangdong Higher Education Institutes, Medical College of Shantou University, Shantou 515041, P. R. China. Department of Biochemistry and Molecular Biology, Medical College of Shantou University, Shantou 515041, P. R. China
| | - Li-Yan Xu
- Key Laboratory of Molecular Biology in High Cancer Incidence Coastal Chaoshan Area of Guangdong Higher Education Institutes, Medical College of Shantou University, Shantou 515041, P. R. China. Institute of Oncologic Pathology, Medical College of Shantou University, Shantou 515041, P. R. China
| | - En-Min Li
- Key Laboratory of Molecular Biology in High Cancer Incidence Coastal Chaoshan Area of Guangdong Higher Education Institutes, Medical College of Shantou University, Shantou 515041, P. R. China. Department of Biochemistry and Molecular Biology, Medical College of Shantou University, Shantou 515041, P. R. China
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102
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Boidot R, Branders S, Helleputte T, Rubio LI, Dupont P, Feron O. A generic cycling hypoxia-derived prognostic gene signature: application to breast cancer profiling. Oncotarget 2015; 5:6947-63. [PMID: 25216520 PMCID: PMC4196175 DOI: 10.18632/oncotarget.2285] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background Temporal and local fluctuations in O2 in tumors require adaptive mechanisms to support cancer cell survival and proliferation. The transcriptome associated with cycling hypoxia (CycHyp) could thus represent a prognostic biomarker of cancer progression. Methods We exposed 20 tumor cell lines to repeated periods of hypoxia/reoxygenation to determine a transcriptomic CycHyp signature and used clinical data sets from 2,150 breast cancer patients to estimate a prognostic Cox proportional hazard model to assess its prognostic performance. Results The CycHyp prognostic potential was validated in patients independently of the receptor status of the tumors. The discriminating capacity of the CycHyp signature was further increased in the ER+ HER2- patient populations including those with a node negative status under treatment (HR=3.16) or not (HR=5.54). The CycHyp prognostic signature outperformed a signature derived from continuous hypoxia and major prognostic metagenes (P<0.001). The CycHyp signature could also identify ER+HER2 node-negative breast cancer patients at high risk based on clinicopathologic criteria but who could have been spared from chemotherapy and inversely those patients classified at low risk based but who presented a negative outcome. Conclusions The CycHyp signature is prognostic of breast cancer and offers a unique decision making tool to complement anatomopathologic evaluation.
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Affiliation(s)
- Romain Boidot
- Institut de Recherche Expérimentale et Clinique (IREC), Pole of Pharmacology and Therapeutics (FATH), Université catholique de Louvain, Brussels, Belgium. These authors contribued equally to this work
| | - Samuel Branders
- Machine Learning Group, Institute of Information and Communication Technologies, Electronics and Applied Mathematics (ICTEAM), Université catholique de Louvain, Louvain-la-Neuve, Belgium. These authors contribued equally to this work
| | - Thibault Helleputte
- Machine Learning Group, Institute of Information and Communication Technologies, Electronics and Applied Mathematics (ICTEAM), Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Laila Illan Rubio
- Institut de Recherche Expérimentale et Clinique (IREC), Pole of Pharmacology and Therapeutics (FATH), Université catholique de Louvain, Brussels, Belgium
| | - Pierre Dupont
- Machine Learning Group, Institute of Information and Communication Technologies, Electronics and Applied Mathematics (ICTEAM), Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Olivier Feron
- Institut de Recherche Expérimentale et Clinique (IREC), Pole of Pharmacology and Therapeutics (FATH), Université catholique de Louvain, Brussels, Belgium
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103
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Hu Z, Zhang D, Wang D, Sun B, Safoor A, Young CYF, Lou H, Yuan H. Bisbibenzyls, novel proteasome inhibitors, suppress androgen receptor transcriptional activity and expression accompanied by activation of autophagy in prostate cancer LNCaP cells. PHARMACEUTICAL BIOLOGY 2015; 54:364-374. [PMID: 26017567 DOI: 10.3109/13880209.2015.1049278] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
CONTEXT Bisbibenzyl compounds have gained our interests for their potential antitumor activity in malignant cell-types. OBJECTIVE The objective of this study is to investigate the effect of bisbibenzyl compounds riccardin C (RC), marchantin M (MM), and riccardin D (RD) on androgen receptor (AR) in prostate cancer (PCa) cells. MATERIALS AND METHODS After exposure to 10 μM of the compounds for 24 h, cell cycle and cell survival analyses were performed using FACS and MTT assay to confirm the effect of these bisbibenzyls on PCa LNCaP cells. Changes in the AR expression and function, as the result of exposure to the compounds, were investigated using real-time PCR, ELISA, transient transfection, western blotting (WB), immunoprecipitation, and immunofluorescence staining (IF). Chemical-induced autophagy was examined by WB, IF, and RNAi. RESULTS RC, MM, and RD reduced the viability of LNCaP cells accompanied with arrested cell cycle in the G0/G1 phase and induction of apoptosis. Further investigation revealed that these compounds significantly inhibited AR expression at mRNA and protein levels, leading to the suppression of AR transcriptional activity. Moreover, inhibition of proteasome activity by bisbibenzyls, which in turn caused the induction of autophagy, as noted by induction of LC3B expression, conversion, and accumulation of punctate dots in treated cells. Co-localization of AR/LC3B and AR/Ub suggested that autophagy contributed to the degradation of polyubiquitinated-AR when proteasome activity was suppressed by the bisbibenzyls. DISCUSSION AND CONCLUSION Suppression of proteasome activity and induction of autophagy were involved in bisbibenzyl-mediated modulation of AR activities and apoptosis, suggesting their potential in treating PCa.
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Affiliation(s)
- Zhongyi Hu
- a Department of Biochemistry and Molecular Biology , Shandong University School of Medicine , Jinan , China
| | - Denglu Zhang
- a Department of Biochemistry and Molecular Biology , Shandong University School of Medicine , Jinan , China
| | - Dawei Wang
- a Department of Biochemistry and Molecular Biology , Shandong University School of Medicine , Jinan , China
| | - Bin Sun
- b Department of Natural Product Chemistry , Shandong University School of Pharmaceutical Sciences , Jinan , China , and
| | - Ayesha Safoor
- a Department of Biochemistry and Molecular Biology , Shandong University School of Medicine , Jinan , China
| | - Charles Y F Young
- c Department of Urology , Mayo Clinic College of Medicine, Mayo Clinic , Rochester , MN , USA
| | - Hongxiang Lou
- b Department of Natural Product Chemistry , Shandong University School of Pharmaceutical Sciences , Jinan , China , and
| | - Huiqing Yuan
- a Department of Biochemistry and Molecular Biology , Shandong University School of Medicine , Jinan , China
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104
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First EA. A continuous spectrophotometric assay for monitoring adenosine 5'-monophosphate production. Anal Biochem 2015; 483:34-9. [PMID: 25957126 DOI: 10.1016/j.ab.2015.04.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 04/24/2015] [Accepted: 04/27/2015] [Indexed: 11/18/2022]
Abstract
A number of biologically important enzymes release adenosine 5'-monophosphate (AMP) as a product, including aminoacyl-tRNA synthetases, cyclic AMP (cAMP) phosphodiesterases, ubiquitin and ubiquitin-like ligases, DNA ligases, coenzyme A (CoA) ligases, polyA deadenylases, and ribonucleases. In contrast to the abundance of assays available for monitoring the conversion of adenosine 5'-triphosphate (ATP) to ADP, there are relatively few assays for monitoring the conversion of ATP (or cAMP) to AMP. In this article, we describe a homogeneous assay that continuously monitors the production of AMP. Specifically, we have coupled the conversion of AMP to inosine 5'-monophosphate (IMP) (by AMP deaminase) to the oxidation of IMP (by IMP dehydrogenase). This results in the reduction of oxidized nicotine adenine dinucleotide (NAD(+)) to reduced nicotine adenine dinucleotide (NADH), allowing AMP formation to be monitored by the change in the absorbance at 340 nm. Changes in AMP concentrations of 5 μM or more can be reliably detected. The ease of use and relatively low expense make the AMP assay suitable for both high-throughput screening and kinetic analyses.
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Affiliation(s)
- Eric A First
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center in Shreveport, Shreveport, LA 71130, USA.
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105
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Obrist F, Manic G, Kroemer G, Vitale I, Galluzzi L. Trial Watch: Proteasomal inhibitors for anticancer therapy. Mol Cell Oncol 2015; 2:e974463. [PMID: 27308423 PMCID: PMC4904962 DOI: 10.4161/23723556.2014.974463] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Revised: 09/15/2014] [Accepted: 09/17/2014] [Indexed: 01/12/2023]
Abstract
The so-called "ubiquitin-proteasome system" (UPS) is a multicomponent molecular apparatus that catalyzes the covalent attachment of several copies of the small protein ubiquitin to other proteins that are generally (but not always) destined to proteasomal degradation. This enzymatic cascade is crucial for the maintenance of intracellular protein homeostasis (both in physiological conditions and in the course of adaptive stress responses), and regulates a wide array of signaling pathways. In line with this notion, defects in the UPS have been associated with aging as well as with several pathological conditions including cardiac, neurodegenerative, and neoplastic disorders. As transformed cells often experience a constant state of stress (as a result of the hyperactivation of oncogenic signaling pathways and/or adverse microenvironmental conditions), their survival and proliferation are highly dependent on the integrity of the UPS. This rationale has driven an intense wave of preclinical and clinical investigation culminating in 2003 with the approval of the proteasomal inhibitor bortezomib by the US Food and Drug Administration for use in multiple myeloma patients. Another proteasomal inhibitor, carfilzomib, is now licensed by international regulatory agencies for use in multiple myeloma patients, and the approved indications for bortezomib have been extended to mantle cell lymphoma. This said, the clinical activity of bortezomib and carfilzomib is often limited by off-target effects, innate/acquired resistance, and the absence of validated predictive biomarkers. Moreover, the antineoplastic activity of proteasome inhibitors against solid tumors is poor. In this Trial Watch we discuss the contribution of the UPS to oncogenesis and tumor progression and summarize the design and/or results of recent clinical studies evaluating the therapeutic profile of proteasome inhibitors in cancer patients.
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Affiliation(s)
- Florine Obrist
- Université Paris-Sud/Paris XI; Le Kremlin-Bicêtre, France
- INSERM, U1138; Paris, France
- Equipe 11 labelisée par la Ligue Nationale contre le Cancer, Center de Recherche des Cordeliers; Paris, France
- Gustave Roussy Cancer Campus; Villejuif, France
| | | | - Guido Kroemer
- INSERM, U1138; Paris, France
- Equipe 11 labelisée par la Ligue Nationale contre le Cancer, Center de Recherche des Cordeliers; Paris, France
- Université Paris Descartes/Paris V; Sorbonne Paris Cité; Paris, France
- Pôle de Biologie, Hôpital Européen Georges Pompidou; Paris, France
- Metabolomics and Cell Biology Platforms; Gustave Roussy Cancer Campus; Villejuif, France
| | - Ilio Vitale
- Regina Elena National Cancer Institute; Rome, Italy
- Department of Biology, University of Rome “Tor Vergata”
| | - Lorenzo Galluzzi
- INSERM, U1138; Paris, France
- Equipe 11 labelisée par la Ligue Nationale contre le Cancer, Center de Recherche des Cordeliers; Paris, France
- Gustave Roussy Cancer Campus; Villejuif, France
- Université Paris Descartes/Paris V; Sorbonne Paris Cité; Paris, France
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106
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Knockdown of ubiquitin protein ligase E3A affects proliferation and invasion, and induces apoptosis of breast cancer cells through regulation of annexin A2. Mol Med Rep 2015; 12:1107-13. [PMID: 25816213 DOI: 10.3892/mmr.2015.3549] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 01/21/2015] [Indexed: 11/05/2022] Open
Abstract
The present study used RNA interference (RNAi) to study how the expression of annexin A2 was affected by ubiquitin protein ligase E3A (UBE3A). In addition, the proliferation, apoptosis and invasiveness of BT-549 breast cancer cells was studied following knockdown of UBE3A. Three pairs of small interfering RNA (siRNA) fragments targeting UBE3A were designed and transfected into the BT-549 cells. The effects of silencing UBE3A were detected by reverse transcription-polymerase chain reaction and western blotting, and the same methods were used to detect the expression levels of annexin A2. Cell proliferation was determined using the Cell Counting kit-8, and flow cytometry and a Transwell chamber assay were used to assess the rate of cell apoptosis and invasion, respectively. Following transfection with the three siRNAs targeting UBE3A for 72 h, the mRNA expression levels of UBE3A were downregulated, as compared with those in the untreated groups, and siRNA1 was the shown to be the most effective siRNA for silencing UBE3A expression. The protein expression levels were concordant with the mRNA expression levels of UBE3A. In addition, the mRNA and protein expression levels of annexin A2 were downregulated. Cellular proliferation and invasion of the siRNA1 group was inhibited as compared with those in the untreated groups, and apoptosis of UBE3A-siRNA1 cells was increased as compared with that in the untreated groups. The results of the present study indicated that UBE3A may regulate the expression of annexin A2, resulting in promotion of proliferation and invasion and suppression of apoptosis in BT-549 cells.
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107
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Seizures are regulated by ubiquitin-specific peptidase 9 X-linked (USP9X), a de-ubiquitinase. PLoS Genet 2015; 11:e1005022. [PMID: 25763846 PMCID: PMC4357451 DOI: 10.1371/journal.pgen.1005022] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 01/22/2015] [Indexed: 01/10/2023] Open
Abstract
Epilepsy is a common disabling disease with complex, multifactorial genetic and environmental etiology. The small fraction of epilepsies subject to Mendelian inheritance offers key insight into epilepsy disease mechanisms; and pathologies brought on by mutations in a single gene can point the way to generalizable therapeutic strategies. Mutations in the PRICKLE genes can cause seizures in humans, zebrafish, mice, and flies, suggesting the seizure-suppression pathway is evolutionarily conserved. This pathway has never been targeted for novel anti-seizure treatments. Here, the mammalian PRICKLE-interactome was defined, identifying prickle-interacting proteins that localize to synapses and a novel interacting partner, USP9X, a substrate-specific de-ubiquitinase. PRICKLE and USP9X interact through their carboxy-termini; and USP9X de-ubiquitinates PRICKLE, protecting it from proteasomal degradation. In forebrain neurons of mice, USP9X deficiency reduced levels of Prickle2 protein. Genetic analysis suggests the same pathway regulates Prickle-mediated seizures. The seizure phenotype was suppressed in prickle mutant flies by the small-molecule USP9X inhibitor, Degrasyn/WP1130, or by reducing the dose of fat facets a USP9X orthologue. USP9X mutations were identified by resequencing a cohort of patients with epileptic encephalopathy, one patient harbored a de novo missense mutation and another a novel coding mutation. Both USP9X variants were outside the PRICKLE-interacting domain. These findings demonstrate that USP9X inhibition can suppress prickle-mediated seizure activity, and that USP9X variants may predispose to seizures. These studies point to a new target for anti-seizure therapy and illustrate the translational power of studying diseases in species across the evolutionary spectrum. Epilepsy is a common disabling disorder characterized by seizures with complex genetic and environmental components. The absence of a definitive pathophysiology for epilepsy stymies the development of effective treatment strategies. In a small fraction of epilepsy cases however, single gene mutations may illuminate seizure-causing mechanisms, which may open the door to the discovery of broader, more effective therapeutic strategies. We have previously shown that disruption of Prickle genes in multiple species including humans, results in a predisposition to seizures. Those findings support Prickle in a seizure-preventing role and presents a possible anti-seizure therapeutic target. We identified the deubiquitinase Usp9x (ubiquitin-specific peptidase 9 X-linked) as a new Prickle binding partner which stabilized Prickle by preventing its degradation. In mice lacking the Usp9x protein in their forebrains, Prickle2 was barely detectable. In seizure-prone prickle mutant Drosophila, reducing fat facets (Drosophila usp9x) genetically or by a small-molecule usp9x inhibitor (Degrasyn/WP1130) suppressed the seizures. We also found 2 epilepsy patients harboring mutations in USP9X. Our findings demonstrate that inhibition of Usp9x can arrest prickle-mediated seizures, and variations in USP9X may predispose to seizures. From these studies, we have elucidated a seizure-inducing mechanism, identified a potential anti-seizure target, and a potential anti-seizure drug.
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108
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Pireyre M, Burow M. Regulation of MYB and bHLH transcription factors: a glance at the protein level. MOLECULAR PLANT 2015; 8:378-88. [PMID: 25667003 DOI: 10.1016/j.molp.2014.11.022] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 11/10/2014] [Accepted: 11/24/2014] [Indexed: 05/07/2023]
Abstract
In complex, constantly changing environments, plants have developed astonishing survival strategies. These elaborated strategies rely on rapid and precise gene regulation mediated by transcription factors (TFs). TFs represent a large fraction of plant genomes and among them, MYBs and basic helix-loop-helix (bHLHs) have unique inherent properties specific to plants. Proteins of these two TF families can act as homo- or heterodimers, associate with proteins from other protein families, or form MYB/bHLH complexes to regulate distinct cellular processes. The ability of MYBs and bHLHs to interact with multiple protein partners has evolved to keep up with the increased metabolic complexity of multi-cellular organisms. Association and disassociation of dynamic TF complexes in response to developmental and environmental cues are controlled through a plethora of regulatory mechanisms specifically modulating TF activity. Regulation of TFs at the protein level is critical for efficient and precise control of their activity, and thus provides the mechanistic basis for a rapid on-and-off switch of TF activity. In this review, examples of post-translational modifications, protein-protein interactions, and subcellular mobilization of TFs are discussed with regard to the relevance of these regulatory mechanisms for the specific activation of MYBs and bHLHs in response to a given environmental stimulus.
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Affiliation(s)
- Marie Pireyre
- DynaMo DNRF Center of Excellence, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Meike Burow
- DynaMo DNRF Center of Excellence, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark.
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109
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Ehm P, Nalaskowski MM, Wundenberg T, Jücker M. The tumor suppressor SHIP1 colocalizes in nucleolar cavities with p53 and components of PML nuclear bodies. Nucleus 2015; 6:154-64. [PMID: 25723258 DOI: 10.1080/19491034.2015.1022701] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The inositol 5-phosphatase SHIP1 is a negative regulator of signaling processes in haematopoietic cells. By converting PI(3,4,5)P3 to PtdIns(3,4)P2 at the plasma membrane, SHIP1 modifies PI3-kinase mediated signaling. We have recently demonstrated that SHIP1 is a nucleo-cytoplasmic shuttling protein and SHIP1 nuclear puncta partially colocalize with FLASH, a component of nuclear bodies. In this study, we demonstrate that endogenous SHIP1 localizes to intranucleolar regions of both normal and leukemic haematopoietic cells. In addition, we report that ectopically expressed SHIP1 accumulates in nucleolar cavities and colocalizes with the tumor suppressor protein p53 and components of PML nuclear bodies (e.g. SP100, SUMO-1 and CK2). Moreover, SHIP1 also colocalizes in nucleolar cavities with components of the ubiquitin-proteasome pathway. By using confocal microscopy data, we generated 3D-models revealing the enormous extent of the SHIP1 aggresomes in the nucleolus. Furthermore, treatment of cells with the proteasome inhibitor MG132 causes an enlargement of nucleolar SHIP1 containing structures. Unexpectedly, this accumulation can be partially prevented by treatment with the inhibitor of nuclear protein export Leptomycin B. In recent years, several proteins aggregating in nucleolar cavities were shown to be key factors of neurodegenerative diseases and cancerogenesis. Our findings support current relevance of nuclear localized SHIP1.
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Key Words
- DFC, dense fibrillar component
- DIC, Differential interference contrast
- EGFP, enhanced green fluorescent protein
- FC, fibrillar center
- GC, granular component
- LMB, leptomycin B
- MG132
- NES, nuclear export signal
- PBMC, Peripheral Blood Mononuclear Cell
- PML bodies
- PML, Promyelocytic Leukemia
- PtdIns(3, 4)P2, phosphatidylinositol-(3, 4)-bisphosphate
- PtdIns(3, 4, 5)P3, phosphatidylinositol-(3, 4, 5)-trisphosphate
- RNA pol, RNA polymerase
- SHIP1
- SHIP1, src homology 2 domain-containing inositol phosphatase 1
- UPP, ubiquitin-proteasome pathway.
- aggresome
- cancer
- leptomycin B
- nucleolar cavities
- nucleus
- p53
- ubiquitin proteasome pathway
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Affiliation(s)
- Patrick Ehm
- a Institute of Biochemistry and Signal Transduction ; University Medical Center Hamburg-Eppendorf ; Hamburg , Germany
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Roles of ubiquitination and SUMOylation on prostate cancer: mechanisms and clinical implications. Int J Mol Sci 2015; 16:4560-80. [PMID: 25734985 PMCID: PMC4394435 DOI: 10.3390/ijms16034560] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 02/09/2015] [Accepted: 02/12/2015] [Indexed: 12/30/2022] Open
Abstract
The initiation and progression of human prostate cancer are highly associated with aberrant dysregulations of tumor suppressors and proto-oncogenes. Despite that deletions and mutations of tumor suppressors and aberrant elevations of oncogenes at the genetic level are reported to cause cancers, emerging evidence has revealed that cancer progression is largely regulated by posttranslational modifications (PTMs) and epigenetic alterations. PTMs play critical roles in gene regulation, cellular functions, tissue development, diseases, malignant progression and drug resistance. Recent discoveries demonstrate that ubiquitination and SUMOylation are complicated but highly-regulated PTMs, and make essential contributions to diseases and cancers by regulation of key factors and signaling pathways. Ubiquitination and SUMOylation pathways can be differentially modulated under various stimuli or stresses in order to produce the sustained oncogenic potentials. In this review, we discuss some new insights about molecular mechanisms on ubiquitination and SUMOylation, their associations with diseases, oncogenic impact on prostate cancer (PCa) and clinical implications for PCa treatment.
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111
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Zhou Y, Zhang N, Li BQ, Huang T, Cai YD, Kong XY. A method to distinguish between lysine acetylation and lysine ubiquitination with feature selection and analysis. J Biomol Struct Dyn 2015; 33:2479-90. [PMID: 25616595 DOI: 10.1080/07391102.2014.1001793] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Lysine acetylation and ubiquitination are two primary post-translational modifications (PTMs) in most eukaryotic proteins. Lysine residues are targets for both types of PTMs, resulting in different cellular roles. With the increasing availability of protein sequences and PTM data, it is challenging to distinguish the two types of PTMs on lysine residues. Experimental approaches are often laborious and time consuming. There is an urgent need for computational tools to distinguish between lysine acetylation and ubiquitination. In this study, we developed a novel method, called DAUFSA (distinguish between lysine acetylation and lysine ubiquitination with feature selection and analysis), to discriminate ubiquitinated and acetylated lysine residues. The method incorporated several types of features: PSSM (position-specific scoring matrix) conservation scores, amino acid factors, secondary structures, solvent accessibilities, and disorder scores. By using the mRMR (maximum relevance minimum redundancy) method and the IFS (incremental feature selection) method, an optimal feature set containing 290 features was selected from all incorporated features. A dagging-based classifier constructed by the optimal features achieved a classification accuracy of 69.53%, with an MCC of .3853. An optimal feature set analysis showed that the PSSM conservation score features and the amino acid factor features were the most important attributes, suggesting differences between acetylation and ubiquitination. Our study results also supported previous findings that different motifs were employed by acetylation and ubiquitination. The feature differences between the two modifications revealed in this study are worthy of experimental validation and further investigation.
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Affiliation(s)
- You Zhou
- a The Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and Shanghai Jiao Tong University School of Medicine , Shanghai 200031 , P.R. China
| | - Ning Zhang
- b Department of Biomedical Engineering, Tianjin Key Lab of BME Measurement , Tianjin University , Tianjin 300072 , P.R. China
| | - Bi-Qing Li
- c Key Laboratory of Systems Biology , Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences , Shanghai 200031 , P.R. China
| | - Tao Huang
- a The Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and Shanghai Jiao Tong University School of Medicine , Shanghai 200031 , P.R. China.,d Department of Genetics and Genomic Sciences , Icahn School of Medicine at Mount Sinai , New York , NY 10029 , USA
| | - Yu-Dong Cai
- e Institute of Systems Biology , Shanghai University , Shanghai 200444 , P.R. China
| | - Xiang-Yin Kong
- a The Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and Shanghai Jiao Tong University School of Medicine , Shanghai 200031 , P.R. China
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Li XL, Zhou J, Chen ZR, Chng WJ. p53 mutations in colorectal cancer- molecular pathogenesis and pharmacological reactivation. World J Gastroenterol 2015; 21:84-93. [PMID: 25574081 PMCID: PMC4284363 DOI: 10.3748/wjg.v21.i1.84] [Citation(s) in RCA: 221] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 08/20/2014] [Accepted: 10/15/2014] [Indexed: 02/06/2023] Open
Abstract
Colorectal cancer (CRC) is one of the most common malignancies with high prevalence and low 5-year survival. CRC is a heterogeneous disease with a complex, genetic and biochemical background. It is now generally accepted that a few important intracellular signaling pathways, including Wnt/β-catenin signaling, Ras signaling, and p53 signaling are frequently dysregulated in CRC. Patients with mutant p53 gene are often resistant to current therapies, conferring poor prognosis. Tumor suppressor p53 protein is a transcription factor inducing cell cycle arrest, senescence, and apoptosis under cellular stress. Emerging evidence from laboratories and clinical trials shows that some small molecule inhibitors exert anti-cancer effect via reactivation and restoration of p53 function. In this review, we summarize the p53 function and characterize its mutations in CRC. The involvement of p53 mutations in pathogenesis of CRC and their clinical impacts will be highlighted. Moreover, we also describe the current achievements of using p53 modulators to reactivate this pathway in CRC, which may have great potential as novel anti-cancer therapy.
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113
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Cao ZQ, Shen Z, Huang WY. MicroRNA-802 promotes osteosarcoma cell proliferation by targeting p27. Asian Pac J Cancer Prev 2015; 14:7081-4. [PMID: 24460254 DOI: 10.7314/apjcp.2013.14.12.7081] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
MicroRNAs have been demonstrated to regulate proliferation and apoptosis in many types of cancers, but biological functions in osteosarcomas remain relatively unknown. Here, we found expression of miR-802 to be up-regulated in osteosarcoma tissues in comparison with adjacent normal tissues. Enforced expression of miR-802 was able to promote cell proliferation in U2OS and MG63 cells, while miR-802 antisense oligonucleotides (antisense miR-802) inhibited cell proliferation. At the molecular level, our results further revealed that expression of p27, a negative cell-cycle regulator, was negatively regulated by miR-802. Therefore, the data reported here indicate that miR-802 is an important regulator in osteosarcoma, our findings contributing to a better understanding of important mis-regulated miRNAs in this tumour type.
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Affiliation(s)
- Zhong-Qing Cao
- Department of Orthopedics, St. Luke's Hospital, Shanghai, China E-mail :
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114
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Peter S, Bultinck J, Myant K, Jaenicke LA, Walz S, Müller J, Gmachl M, Treu M, Boehmelt G, Ade CP, Schmitz W, Wiegering A, Otto C, Popov N, Sansom O, Kraut N, Eilers M. Tumor cell-specific inhibition of MYC function using small molecule inhibitors of the HUWE1 ubiquitin ligase. EMBO Mol Med 2014; 6:1525-41. [PMID: 25253726 PMCID: PMC4287973 DOI: 10.15252/emmm.201403927] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Revised: 07/30/2014] [Accepted: 08/26/2014] [Indexed: 12/14/2022] Open
Abstract
Deregulated expression of MYC is a driver of colorectal carcinogenesis, necessitating novel strategies to inhibit MYC function. The ubiquitin ligase HUWE1 (HECTH9, ARF-BP1, MULE) associates with both MYC and the MYC-associated protein MIZ1. We show here that HUWE1 is required for growth of colorectal cancer cells in culture and in orthotopic xenograft models. Using high-throughput screening, we identify small molecule inhibitors of HUWE1, which inhibit MYC-dependent transactivation in colorectal cancer cells, but not in stem and normal colon epithelial cells. Inhibition of HUWE1 stabilizes MIZ1. MIZ1 globally accumulates on MYC target genes and contributes to repression of MYC-activated target genes upon HUWE1 inhibition. Our data show that transcriptional activation by MYC in colon cancer cells requires the continuous degradation of MIZ1 and identify a novel principle that allows for inhibition of MYC function in tumor cells.
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Affiliation(s)
- Stefanie Peter
- Theodor Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Jennyfer Bultinck
- Cytokine Receptor Lab, Department of Biochemistry, Ghent University, Ghent, Belgium
| | | | - Laura A Jaenicke
- Theodor Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Susanne Walz
- Theodor Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Judith Müller
- Department of Molecular Oncology, Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Michael Gmachl
- Department Lead Discovery, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Matthias Treu
- Department Lead Discovery, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Guido Boehmelt
- Department Lead Discovery, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Carsten P Ade
- Theodor Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Werner Schmitz
- Theodor Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Armin Wiegering
- Department of General, Visceral, Vascular and Paediatric Surgery, University Hospital Würzburg, Würzburg, Germany
| | - Christoph Otto
- Department of General, Visceral, Vascular and Paediatric Surgery, University Hospital Würzburg, Würzburg, Germany
| | - Nikita Popov
- Theodor Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany
| | | | - Norbert Kraut
- Department Lead Discovery, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Martin Eilers
- Theodor Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany
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115
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HSP90 regulates DNA repair via the interaction between XRCC1 and DNA polymerase β. Nat Commun 2014; 5:5513. [PMID: 25423885 PMCID: PMC4246423 DOI: 10.1038/ncomms6513] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 10/07/2014] [Indexed: 02/06/2023] Open
Abstract
Cellular DNA repair processes are crucial to maintain genome stability and integrity. In DNA base excision repair, a tight heterodimer complex formed by DNA polymerase β (Polβ) and XRCC1 is thought to facilitate repair by recruiting Polβ to DNA damage sites. Here we show that disruption of the complex does not impact DNA damage response or DNA repair. Instead, the heterodimer formation is required to prevent ubiquitylation and degradation of Polβ. In contrast, the stability of the XRCC1 monomer is protected from CHIP-mediated ubiquitylation by interaction with the binding partner HSP90. In response to cellular proliferation and DNA damage, proteasome and HSP90-mediated regulation of Polβ and XRCC1 alters the DNA repair complex architecture. We propose that protein stability, mediated by DNA repair protein complex formation, functions as a regulatory mechanism for DNA repair pathway choice in the context of cell cycle progression and genome surveillance.
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Cai F, Chen P, Chen L, Biskup E, Liu Y, Chen PC, Chang JF, Jiang W, Jing Y, Chen Y, Jin H, Chen S. Human RAD6 promotes G1-S transition and cell proliferation through upregulation of cyclin D1 expression. PLoS One 2014; 9:e113727. [PMID: 25409181 PMCID: PMC4237501 DOI: 10.1371/journal.pone.0113727] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 10/28/2014] [Indexed: 11/19/2022] Open
Abstract
Protein ubiquitinylation regulates protein stability and activity. RAD6, an E2 ubiquitin-conjugating enzyme, which that has been substantially biochemically characterized, functions in a number of biologically relevant pathways, including cell cycle progression. In this study, we show that RAD6 promotes the G1-S transition and cell proliferation by regulating the expression of cyclin D1 (CCND1) in human cells. Furthermore, our data indicate that RAD6 influences the transcription of CCND1 by increasing monoubiquitinylation of histone H2B and trimethylation of H3K4 in the CCND1 promoter region. Our study presents, for the first time, an evidence for the function of RAD6 in cell cycle progression and cell proliferation in human cells, raising the possibility that RAD6 could be a new target for molecular diagnosis and prognosis in cancer therapeutics.
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Affiliation(s)
- Fengfeng Cai
- School of Life Sciences and Technology, Department of Breast Surgery of Yangpu Hospital, Research Center for Translational Medicine at East Hospital, Tongji University, Shanghai, P. R. China
| | - Ping Chen
- School of Life Sciences and Technology, Department of Breast Surgery of Yangpu Hospital, Research Center for Translational Medicine at East Hospital, Tongji University, Shanghai, P. R. China
| | - Li Chen
- School of Life Sciences and Technology, Department of Breast Surgery of Yangpu Hospital, Research Center for Translational Medicine at East Hospital, Tongji University, Shanghai, P. R. China
| | - Ewelina Biskup
- Department of Oncology, University Hospital of Basel, Basel, Switzerland
| | - Yan Liu
- College of Life Sciences, Hebei United University, Tangshan, Hebei Province, P. R. China
- The Cancer Institute, Tangshan People’s Hospital, Tangshan, Hebei Province, P. R. China
| | - Pei-Chao Chen
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou, Zhejiang Province, P. R. China
| | - Jian-Feng Chang
- School of Life Sciences and Technology, Department of Breast Surgery of Yangpu Hospital, Research Center for Translational Medicine at East Hospital, Tongji University, Shanghai, P. R. China
| | - Wenjie Jiang
- School of Life Sciences and Technology, Department of Breast Surgery of Yangpu Hospital, Research Center for Translational Medicine at East Hospital, Tongji University, Shanghai, P. R. China
| | - Yuanya Jing
- School of Life Sciences and Technology, Department of Breast Surgery of Yangpu Hospital, Research Center for Translational Medicine at East Hospital, Tongji University, Shanghai, P. R. China
| | - Youwei Chen
- School of Life Sciences and Technology, Department of Breast Surgery of Yangpu Hospital, Research Center for Translational Medicine at East Hospital, Tongji University, Shanghai, P. R. China
| | - Hui Jin
- Department of Biochemistry and Molecular Cell Biology, School of Medcine, Shanghai Jiao Tong University, Shanghai, P. R. China
- * E-mail: (SC); (HJ)
| | - Su Chen
- School of Life Sciences and Technology, Department of Breast Surgery of Yangpu Hospital, Research Center for Translational Medicine at East Hospital, Tongji University, Shanghai, P. R. China
- * E-mail: (SC); (HJ)
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Abstract
The human genome encodes several hundred E3 ubiquitin ligases containing RING domains, and around 28 containing HECT domains. These enzymes catalyze the transfer of ubiquitin from E2 enzyme thioesters to a huge range of substrates and play crucial roles in many cellular functions. This makes them attractive potential therapeutic targets. However, they have proven difficult to inhibit: very few good inhibitors exist for RING domain ligases, and none have been described for HECT ligases. Here we show that bicyclic peptides isolated by phage display [Heinis C, Rutherford T, Freund S, Winter G (2009) Nat Chem Biol. 5(7):502-507] can target the E2 binding sites on the HECT domains of Smurf2, Nedd4, Mule/Huwe1, and WWP1, and thus act as specific inhibitors of these enzymes in vitro. By screening for displacement of one of these peptides from Smurf2, we were able to identify a small molecule, heclin (HECT ligase inhibitor), which inhibits several HECT ligases in tissue culture cells. In vitro, heclin does not block E2 binding but causes a conformational change that results in oxidation of the active site Cys. This demonstrates that HECT domains are potentially druggable and provides molecules that may be of experimental use. Heclin kills HEK293 cells growing in culture, consistent with an essential role for HECT ligase activity in mammalian cells.
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Horton TM, Perentesis JP, Gamis AS, Alonzo TA, Gerbing RB, Ballard J, Adlard K, Howard DS, Smith FO, Jenkins G, Kelder A, Schuurhuis GJ, Moscow JA. A Phase 2 study of bortezomib combined with either idarubicin/cytarabine or cytarabine/etoposide in children with relapsed, refractory or secondary acute myeloid leukemia: a report from the Children's Oncology Group. Pediatr Blood Cancer 2014; 61:1754-60. [PMID: 24976003 PMCID: PMC4247259 DOI: 10.1002/pbc.25117] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 05/05/2014] [Indexed: 12/20/2022]
Abstract
BACKGROUND This Phase 2 study tested the tolerability and efficacy of bortezomib combined with reinduction chemotherapy for pediatric patients with relapsed, refractory or secondary acute myeloid leukemia (AML). Correlative studies measured putative AML leukemia initiating cells (AML-LIC) before and after treatment. PROCEDURE Patients with <400 mg/m(2) prior anthracycline received bortezomib combined with idarubicin (12 mg/m(2) days 1-3) and low-dose cytarabine (100 mg/m(2) days 1-7) (Arm A). Patients with ≥400 mg/m(2) prior anthracycline received bortezomib with etoposide (100 mg/m(2) on days 1-5) and high-dose cytarabine (1 g/m(2) every 12 hours for 10 doses) (Arm B). RESULTS Forty-six patients were treated with 58 bortezomib-containing cycles. The dose finding phase of Arm B established the recommended Phase 2 dose of bortezomib at 1.3 mg/m(2) on days 1, 4, and 8 with Arm B chemotherapy. Both arms were closed after failure to meet predetermined efficacy thresholds during the first stage of the two-stage design. The complete response (CR + CRp) rates were 29% for Arm A and 43% for Arm B. Counting additional CRi responses (CR with incomplete neutrophil recovery), the overall CR rates were 57% for Arm A and 48% for Arm B. The 2-year overall survival (OS) was 39 ± 15%. Correlative studies showed that LIC depletion after the first cycle was associated with clinical response. CONCLUSION Bortezomib is tolerable when added to chemotherapy regimens for relapsed pediatric AML, but the regimens did not exceed preset minimum response criteria to allow continued accrual. This study also suggests that AML-LIC depletion has prognostic value.
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Affiliation(s)
- Terzah M. Horton
- Texas Children's Cancer and Hematology Centers at Baylor College of Medicine, Houston, Texas
| | | | - Alan S. Gamis
- Children's Mercy Hospitals & Clinics, Kansas City, Missouri
| | - Todd A. Alonzo
- Keck School of Medicine, University of Southern California, Los Angeles, California
- Children's Oncology Group—Operations Center, Monrovia, California
| | | | - Jennifer Ballard
- Department of Pediatrics, University of Kentucky, Lexington, Kentucky
| | | | - Dianna S. Howard
- Division of Hematology and Oncology, Wake Forest University, Winston-Salem, NC
| | - Franklin O. Smith
- Division of Hematology/Oncology, Department of Internal Medicine, University of Cincinnati Cancer Institute, Cincinnati, Ohio
| | - Gaye Jenkins
- Texas Children's Cancer and Hematology Centers at Baylor College of Medicine, Houston, Texas
| | - Angelé Kelder
- Department of Hematology, VU University Medical Center, Amsterdam, the Netherlands
| | - Gerrit J. Schuurhuis
- Department of Hematology, VU University Medical Center, Amsterdam, the Netherlands
| | - Jeffrey A. Moscow
- Department of Pediatrics, University of Kentucky, Lexington, Kentucky
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119
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Meng W, Wang PS, Liu J, Xue S, Wang GM, Meng XY, Chen G. Adenovirus-mediated siRNA targeting NOB1 inhibits tumor growth and enhances radiosensitivity of human papillary thyroid carcinoma in vitro and in vivo. Oncol Rep 2014; 32:2411-20. [PMID: 25231838 DOI: 10.3892/or.2014.3483] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Accepted: 08/12/2014] [Indexed: 11/05/2022] Open
Abstract
NIN1/RPN12 binding protein 1 homolog (NOB1), a ribosome assembly factor, plays critical roles in tumor progression and development. Previously, we reported that overexpression of NOB1 is correlated with the prognosis of patients with papillary thyroid carcinoma (PTC). Little is known, however, concerning its role in PTC. The aims of the present study were to investigate the association of NOB1 expression with tumor growth and radiosensitivity of human PTC. A recombinant adenovirus expression vector carrying NOB1 was constructed and then infected into the human PTC cell line TPC-1. Cell proliferation, cell cycle distribution, apoptosis, migration and invasion in vitro and tumor growth in vivo were determined after downregulation of NOB1 by RNAi. Additionally, the in vitro and in vivo radiosensitivity of PTC cells was determined by clonogenic cell survival assay and a mouse xenograft model, respectively. The results showed that downregulation of NOB1 expression using RNAi in TPC-1 cells significantly inhibited cell proliferation, migration and invasion and induced cell apoptosis in vitro, and suppressed tumor growth in vivo, as well as enhanced the in vitro and in vivo radiosensitivity of PTC cells. Moreover, our results also showed that downregulation of NOB1 was able to significantly activate constitutive phosphorylation of p38 MAPK, which might contribute to the inhibition of PTC cell growth. These findings suggest that NOB1 may be a potential therapeutic target for the treatment of PTC.
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Affiliation(s)
- Wei Meng
- Department of Thyroid Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Pei-Song Wang
- Department of Thyroid Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Jia Liu
- Department of Thyroid Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Shuai Xue
- Department of Thyroid Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Gui-Min Wang
- Department of Thyroid Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Xian-Ying Meng
- Department of Thyroid Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Guang Chen
- Department of Thyroid Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
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Ju D, Xie Y. Dyclonine enhances the cytotoxic effect of proteasome inhibitor bortezomib in multiple myeloma cells. Mol Med Rep 2014; 10:2609-12. [PMID: 25174315 DOI: 10.3892/mmr.2014.2522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 04/09/2014] [Indexed: 11/05/2022] Open
Abstract
The proteasome has become an important target for cancer therapy with the approval of bortezomib for the treatment of relapsed/refractory multiple myeloma (MM). However, numerous patients with MM do not respond to bortezomib and those responding initially often acquire resistance. Recent clinical studies have also demonstrated that bortezomib is also inefficacious in the treatment of other types of cancer. Therefore, it is imperative to develop novel approaches and agents for proteasome-targeting cancer therapy. In the present study, it was revealed that dyclonine, a major component of the cough droplets Sucrets, markedly enhances the cytotoxic effects of bortezomib and minimizes drug resistance in MM cells. It was demonstrated that a combination of bortezomib and dyclonine markedly induced apoptosis of MM cells. The present study suggests a novel therapeutic use of an over‑the‑counter medicine for the treatment of MM.
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Affiliation(s)
- Donghong Ju
- Karmanos Cancer Institute, Department of Oncology and Pathology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Youming Xie
- Karmanos Cancer Institute, Department of Oncology and Pathology, Wayne State University School of Medicine, Detroit, MI 48201, USA
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121
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Wang Z, Wang J, Li X, Xing L, Ding Y, Shi P, Zhang Y, Guo S, Shu X, Shan B. Bortezomib prevents oncogenesis and bone metastasis of prostate cancer by inhibiting WWP1, Smurf1 and Smurf2. Int J Oncol 2014; 45:1469-78. [PMID: 25051198 DOI: 10.3892/ijo.2014.2545] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 06/06/2014] [Indexed: 11/06/2022] Open
Abstract
Prostate cancer is the most common malignancy diagnosed in males, and bone metastases remain a significant source of morbidity and mortality in this population. Ubiquitin ligase E3s and proteasomes were thought to play essential roles in the development of cancers, therefore, they were proposed as therapy targets for the treatment of solid and hematological malignancies. Bortezomib, well-known as a proteasome inhibitor, has been observed with exact anticancer effect both in cell and animal models for several solid tumor types, including prostate cancer. To explore activities of the ubiquitin ligase E3s WWP1, Smurf1 and Smurf2 in oncogenesis and bone metastasis of prostate cancer, as well as in the functional mechanism of bortezomib in preventing prostate cancer, transcription and expression levels of WWP1, Smurf1 and Smurf2 genes in cell lines or tissues of benign prostate hyperplasia and human prostate cancer with and without bone metastasis were tested. Moreover, human prostate cancer PC3 cell lines were treated with bortezomib at different concentration gradients and then their proliferation at different time points, mRNA and protein levels were investigated. The results indicated that transcription and expression levels of WWP1, Smurf1 and Smurf2 genes in prostate cancer without bone metastasis were significantly higher compared to those in benign prostate hyperplasia (P<0.05), whereas significantly lower than prostate cancer metastatic to bone (P<0.05). Furthermore, bortezomib reduced the transcription and expression levels of WWP1, Smurf1 and Smurf2 genes in prostate cancer cell lines in a dose-dependent manner, thus, inhibiting the proliferation of prostate cancer cells. Elevated transcription and expression levels of ubiquitin ligase E3s WWP1, Smurf1 and Smurf2 genes may be the mechanisms of occurrence, development and metastasis of prostate cancer. In addition, bortezomib can prevent prostate cancer and its bone metastasis by downregulating WWP1, Smurf1 and Smurf2.
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Affiliation(s)
- Zhiyu Wang
- Department of Immunology and Immunotherapy, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China
| | - Juan Wang
- Department of Immunology and Immunotherapy, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China
| | - Xing Li
- Department of Immunology and Immunotherapy, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China
| | - Lianping Xing
- University of Rochester School of Medicine and Dentistry, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Yan Ding
- Department of Pathology, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China
| | - Penghui Shi
- Department of Immunology and Immunotherapy, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China
| | - Yuehua Zhang
- Department of Immunology and Immunotherapy, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China
| | - Shenghu Guo
- Department of Immunology and Immunotherapy, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China
| | - Xin Shu
- Department of Oncology, Armed Police General Hospital, Beijing 100039, P.R. China
| | - Baoen Shan
- Scientific Research Centre, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China
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Exploring the RING-catalyzed ubiquitin transfer mechanism by MD and QM/MM calculations. PLoS One 2014; 9:e101663. [PMID: 25003393 PMCID: PMC4086935 DOI: 10.1371/journal.pone.0101663] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2014] [Accepted: 06/09/2014] [Indexed: 11/19/2022] Open
Abstract
Ubiquitylation is a universal mechanism for controlling cellular functions. A large family of ubiquitin E3 ligases (E3) mediates Ubiquitin (Ub) modification. To facilitate Ub transfer, RING E3 ligases bind both the substrate and ubiquitin E2 conjugating enzyme (E2) linked to Ub via a thioester bond to form a catalytic complex. The mechanism of Ub transfer catalyzed by RING E3 remains elusive. By employing a combined computational approach including molecular modeling, molecular dynamics (MD) simulations, and quantum mechanics/molecular mechanics (QM/MM) calculations, we characterized this catalytic mechanism in detail. The three-dimensional model of dimeric RING E3 ligase RNF4 RING, E2 ligase UbcH5A, Ub and the substrate SUMO2 shows close contact between the substrate and Ub transfer catalytic center. Deprotonation of the substrate lysine by D117 on UbcH5A occurs with almost no energy barrier as calculated by MD and QM/MM calculations. Then, the side chain of the activated lysine gets close to the thioester bond via a conformation change. The Ub transfer pathway begins with a nucleophilic addition that forms an oxyanion intermediate of a 4.23 kcal/mol energy barrier followed by nucleophilic elimination, resulting in a Ub modified substrate by a 5.65 kcal/mol energy barrier. These results provide insight into the mechanism of RING-catalyzed Ub transfer guiding the discovery of Ub system inhibitors.
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123
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Jiang JH, Liu YF, Ke AW, Gu FM, Yu Y, Dai Z, Gao Q, Shi GM, Liao BY, Xie YH, Fan J, Huang XW, Zhou J. Clinical significance of the ubiquitin ligase UBE3C in hepatocellular carcinoma revealed by exome sequencing. Hepatology 2014; 59:2216-27. [PMID: 24425307 DOI: 10.1002/hep.27012] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 01/10/2014] [Indexed: 12/29/2022]
Abstract
UNLABELLED Virus-induced hepatocarcinogenesis involves a series of histological developmental processes with the stepwise acquisition of several genetic changes that are necessary for the malignant transformation of hepatocytes. Although genetic alterations are known to be involved in the pathogenesis of hepatocellular carcinoma (HCC), little is known about the contributions of specific genes to this process. To gain insight into the genetic alterations involved in the neoplastic evolution from chronic hepatitis B virus infection to dysplastic nodules (DN) to HCC, we captured and sequenced the exomes of four DNA samples: one DN sample, two HCC samples, and one control peripheral blood sample from a single HCC patient. Mutations in the UBE3C gene (encoding ubiquitin ligase E3C) were observed in both tumor tissues. Then we resequenced the UBE3C gene in a cohort of 105 HCC patients and identified mutations in 17 out of a total of 106 (16.0%) HCC patients. The subsequent experiments showed that UBE3C promoted HCC progression by regulating HCC cells epithelial-mesenchymal transition. Clinically, a tissue microarray study of a cohort containing 323 HCC patients revealed that the overexpression of UBE3C in primary HCC tissues correlated with decreased survival (hazard ratio [HR] =1.657, 95% confidence interval [CI] =1.220-2.251, P=0.001) and early tumor recurrence (HR=1.653, 95% CI=1.227-2.228, P=0.001) in postoperative HCC patients. CONCLUSION Our findings indicate that UBE3C is a candidate oncogene involved in tumor development and progression and therefore a potential therapeutic target in applicable HCC patients.
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Affiliation(s)
- Jia-Hao Jiang
- Liver Cancer Institute, Zhongshan Hospital, Fudan University; Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Shanghai, P.R. China
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Zaglia T, Milan G, Ruhs A, Franzoso M, Bertaggia E, Pianca N, Carpi A, Carullo P, Pesce P, Sacerdoti D, Sarais C, Catalucci D, Krüger M, Mongillo M, Sandri M. Atrogin-1 deficiency promotes cardiomyopathy and premature death via impaired autophagy. J Clin Invest 2014; 124:2410-24. [PMID: 24789905 DOI: 10.1172/jci66339] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Cardiomyocyte proteostasis is mediated by the ubiquitin/proteasome system (UPS) and autophagy/lysosome system and is fundamental for cardiac adaptation to both physiologic (e.g., exercise) and pathologic (e.g., pressure overload) stresses. Both the UPS and autophagy/lysosome system exhibit reduced efficiency as a consequence of aging, and dysfunction in these systems is associated with cardiomyopathies. The muscle-specific ubiquitin ligase atrogin-1 targets signaling proteins involved in cardiac hypertrophy for degradation. Here, using atrogin-1 KO mice in combination with in vivo pulsed stable isotope labeling of amino acids in cell culture proteomics and biochemical and cellular analyses, we identified charged multivesicular body protein 2B (CHMP2B), which is part of an endosomal sorting complex (ESCRT) required for autophagy, as a target of atrogin-1-mediated degradation. Mice lacking atrogin-1 failed to degrade CHMP2B, resulting in autophagy impairment, intracellular protein aggregate accumulation, unfolded protein response activation, and subsequent cardiomyocyte apoptosis, all of which increased progressively with age. Cellular proteostasis alterations resulted in cardiomyopathy characterized by myocardial remodeling with interstitial fibrosis, with reduced diastolic function and arrhythmias. CHMP2B downregulation in atrogin-1 KO mice restored autophagy and decreased proteotoxicity, thereby preventing cell death. These data indicate that atrogin-1 promotes cardiomyocyte health through mediating the interplay between UPS and autophagy/lysosome system and its alteration promotes development of cardiomyopathies.
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125
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Stintzing S, Lenz HJ. Molecular pathways: turning proteasomal protein degradation into a unique treatment approach. Clin Cancer Res 2014; 20:3064-70. [PMID: 24756373 DOI: 10.1158/1078-0432.ccr-13-3175] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Cancer treatment regimens have evolved from single cytotoxic substances affecting all proliferative tissues toward antibodies and kinase inhibitors targeting tumor-specific pathways. Treatment efficacy and cancer survival have improved overall, and side effects have become less frequent. The ubiquitin-proteasome system-mediated proteasomal protein degradation is the most critical pathway to regulate the quantity of signal proteins involved in carcinogenesis and tumor progression. These processes are, as well as protein recycling, highly regulated and offer targets for biomarker and drug development. Unspecific proteasome inhibitors such as bortezomib and carfilzomib have shown clinical efficacy and are approved for clinical use. Inhibitors of more substrate-specific enzymes of degradation processes are being developed and are now in early clinical trials. The novel compounds focus on the degradation of key regulatory proteins such as p53, p27(Kip1), and ß-catenin, and inhibitors specific for growth factor receptor kinase turnover are in preclinical testing.
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Affiliation(s)
- Sebastian Stintzing
- Authors' Affiliation: USC/Norris Comprehensive Cancer Center, Keck School of Medicine, Sharon Carpenter Laboratory, Los Angeles, California
| | - Heinz-Josef Lenz
- Authors' Affiliation: USC/Norris Comprehensive Cancer Center, Keck School of Medicine, Sharon Carpenter Laboratory, Los Angeles, California
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126
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Lill JR, Wertz IE. Toward understanding ubiquitin-modifying enzymes: from pharmacological targeting to proteomics. Trends Pharmacol Sci 2014; 35:187-207. [PMID: 24717260 DOI: 10.1016/j.tips.2014.01.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 01/24/2014] [Accepted: 01/24/2014] [Indexed: 11/20/2022]
Abstract
Ubiquitination is a highly conserved post-translational modification that regulates protein trafficking, function, and turnover. Ubiquitin ligases (E3s) conjugate ubiquitin polypeptides on substrates, whereas deubiquitnases (DUBs) reverse ubiquitination. Engineering of chemical antagonists and inhibitors of ubiquitin ligases and DUBs has considerably aided the study of enzymes that participate in ubiquitin modification of substrates. In addition, proteomic tools have been developed to characterize the enzymes, substrates, and modifications regulated by DUBs and E3s. Here we review inhibitors and antagonists that have been developed against DUBs and E3s, focusing on enzymes that participate in ubiquitin editing or in the reciprocal ubiquitin regulation of substrates. We outline the cellular biology that is regulated by these DUBs and E3s and highlight how the inhibitory compounds have improved our understanding of these pathways. Finally, we discuss the challenges and future directions for pharmacologically targeting ubiquitin-modifying enzymes, as well as the development of proteomic methods to evaluate ubiquitin modification of substrates.
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Affiliation(s)
- Jennie R Lill
- Department of Protein Chemistry, Genentech, Inc., 1 DNA Way, M/S 413A, South San Francisco, CA 94080, USA.
| | - Ingrid E Wertz
- Department of Early Discovery Biochemistry, Genentech, Inc., 1 DNA Way, M/S 40, South San Francisco, CA 94080, USA.
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127
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Lopez-Serra P, Marcilla M, Villanueva A, Ramos-Fernandez A, Palau A, Leal L, Wahi JE, Setien-Baranda F, Szczesna K, Moutinho C, Martinez-Cardus A, Heyn H, Sandoval J, Puertas S, Vidal A, Sanjuan X, Martinez-Balibrea E, Viñals F, Perales JC, Bramsem JB, Ørntoft TF, Andersen CL, Tabernero J, McDermott U, Boxer MB, Heiden MGV, Albar JP, Esteller M. A DERL3-associated defect in the degradation of SLC2A1 mediates the Warburg effect. Nat Commun 2014; 5:3608. [PMID: 24699711 PMCID: PMC3988805 DOI: 10.1038/ncomms4608] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 03/10/2014] [Indexed: 01/03/2023] Open
Abstract
Cancer cells possess aberrant proteomes that can arise by the disruption of genes involved in physiological protein degradation. Here we demonstrate the presence of promoter CpG island hypermethylation-linked inactivation of DERL3 (Derlin-3), a key gene in the endoplasmic reticulum-associated protein degradation pathway, in human tumours. The restoration of in vitro and in vivo DERL3 activity highlights the tumour suppressor features of the gene. Using the stable isotopic labelling of amino acids in cell culture workflow for differential proteome analysis, we identify SLC2A1 (glucose transporter 1, GLUT1) as a downstream target of DERL3. Most importantly, SLC2A1 overexpression mediated by DERL3 epigenetic loss contributes to the Warburg effect in the studied cells and pinpoints a subset of human tumours with greater vulnerability to drugs targeting glycolysis.
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Affiliation(s)
- Paula Lopez-Serra
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, 08908 Catalonia, Spain
| | - Miguel Marcilla
- Proteomics Unit, Spanish National Biotechnology Centre (CNB), CSIC, 28049 Madrid, Spain
| | - Alberto Villanueva
- Translational Research Laboratory, Catalan Institute of Oncology (ICO), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, 08908 Catalonia, Spain
| | | | - Anna Palau
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, 08908 Catalonia, Spain
| | - Lucía Leal
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, 08908 Catalonia, Spain
| | - Jessica E. Wahi
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, 08908 Catalonia, Spain
| | - Fernando Setien-Baranda
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, 08908 Catalonia, Spain
| | - Karolina Szczesna
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, 08908 Catalonia, Spain
| | - Catia Moutinho
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, 08908 Catalonia, Spain
| | - Anna Martinez-Cardus
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, 08908 Catalonia, Spain
| | - Holger Heyn
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, 08908 Catalonia, Spain
| | - Juan Sandoval
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, 08908 Catalonia, Spain
| | - Sara Puertas
- Translational Research Laboratory, Catalan Institute of Oncology (ICO), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, 08908 Catalonia, Spain
| | - August Vidal
- Bellvitge Biomedical Research Institute (IDIBELL), Department of Pathology, Bellvitge University Hospital, L'Hospitalet, Barcelona, 08908 Catalonia, Spain
| | - Xavier Sanjuan
- Bellvitge Biomedical Research Institute (IDIBELL), Department of Pathology, Bellvitge University Hospital, L'Hospitalet, Barcelona, 08908 Catalonia, Spain
| | - Eva Martinez-Balibrea
- Medical Oncology Service, Catalan Institute of Oncology (ICO), l'Institut d'Investigació en Ciències de la Salut Germans Trias i Pujol (IGTP), Hospital Germans Trias I Pujol, Badalona, Barcelona, 08916 Catalonia, Spain
| | - Francesc Viñals
- Translational Research Laboratory, Catalan Institute of Oncology (ICO), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, 08908 Catalonia, Spain
- Department of Physiological Sciences II, School of Medicine, University of Barcelona, 08036 Barcelona, Spain
| | - Jose C. Perales
- Department of Physiological Sciences II, School of Medicine, University of Barcelona, 08036 Barcelona, Spain
| | - Jesper B. Bramsem
- Department of Molecular Medicine, Aarhus University Hospital, Brendstrupgaardsvej 100, Aarhus N, DK-8200 Aarhus, Denmark
| | - Torben F. Ørntoft
- Department of Molecular Medicine, Aarhus University Hospital, Brendstrupgaardsvej 100, Aarhus N, DK-8200 Aarhus, Denmark
| | - Claus L. Andersen
- Department of Molecular Medicine, Aarhus University Hospital, Brendstrupgaardsvej 100, Aarhus N, DK-8200 Aarhus, Denmark
| | - Josep Tabernero
- Medical Oncology Department, Vall d’Hebron University Hospital, Barcelona, 08035 Catalonia, Spain
| | - Ultan McDermott
- Cancer Genome Project, Wellcome Trust Sanger Institute, Hinxton CB10 1SA, UK
| | - Matthew B. Boxer
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20891-4874, USA
| | - Matthew G. Vander Heiden
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA
| | - Juan Pablo Albar
- Proteomics Unit, Spanish National Biotechnology Centre (CNB), CSIC, 28049 Madrid, Spain
| | - Manel Esteller
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet, Barcelona, 08908 Catalonia, Spain
- Department of Physiological Sciences II, School of Medicine, University of Barcelona, 08036 Barcelona, Spain
- Institucio Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, 08010 Catalonia, Spain
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128
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Zhu J, Deng S, Duan J, Xie X, Xu S, Ran M, Dai X, Pu Y, Zhang X. FBXL20 acts as an invasion inducer and mediates E-cadherin in colorectal adenocarcinoma. Oncol Lett 2014; 7:2185-2191. [PMID: 24932313 PMCID: PMC4049678 DOI: 10.3892/ol.2014.2031] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 03/20/2014] [Indexed: 01/05/2023] Open
Abstract
The mechanisms eliciting colorectal adenocarcinoma are not well understood and the FBXL20 gene is problematic as it exhibits an abnormal expression in colorectal cancer cells. In the present study a recombinant plasmid, pReceiver-M03-FBL20 expression plasmid was constructed, which overexpressed FBXL20; this was transfected into Lovo cells to form Lovo-FBL20 cells. The FBXL20 expression level was examined by quantitative polymerase chain reaction (qPCR) and western blot analysis. The cell viability and invasion capacity were measured using cell counting kit 8, Transwell chamber and wound healing assays, respectively. The associated genes, including E-cadherin, β-catenin, c-Myc, SET nuclear oncogene, protein phosphatase-2A, Axin, p53 and caspase 3, were detected by qPCR and western blotting. It was demonstrated that the FBXL20 expression level was markedly upregulated in the Lovo-FBL20 cells transfected with pReceiver-M03-FBL20 expression plasmid, compared with that of the Lovo cells. In addition, the cell viability and invasion capacity of the Lovo-FBL20 cells were significantly increased. These increases correlated with a significant upregulation in the expression level of β-catenin and c-Myc, and a downregulated expression level of E-cadherin. The results of the present study indicate that FBXL20 may mediate the ubiquitin degradation of E-cadherin resulting in an increased invasive ability of malignant cells.
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Affiliation(s)
- Jianjun Zhu
- Department of Human Anatomy, Premedical College, North Sichuan Medical College, Nanchong, Sichuan 637000, P.R. China
| | - Shishan Deng
- Department of Human Anatomy, Premedical College, North Sichuan Medical College, Nanchong, Sichuan 637000, P.R. China
| | - Jie Duan
- Department of Neurosurgery, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan 637000, P.R. China
| | - Xingguo Xie
- Department of Human Anatomy, Premedical College, North Sichuan Medical College, Nanchong, Sichuan 637000, P.R. China
| | - Shiquan Xu
- Department of Human Anatomy, Premedical College, North Sichuan Medical College, Nanchong, Sichuan 637000, P.R. China
| | - Maocheng Ran
- Department of Human Anatomy, Premedical College, North Sichuan Medical College, Nanchong, Sichuan 637000, P.R. China
| | - Xiaosi Dai
- Department of Human Anatomy, Premedical College, North Sichuan Medical College, Nanchong, Sichuan 637000, P.R. China
| | - Yu Pu
- Sichuan Key Laboratory of Medical Imaging, Nanchong, Sichuan 637000, P.R. China
| | - Xiaoming Zhang
- Sichuan Key Laboratory of Medical Imaging, Nanchong, Sichuan 637000, P.R. China
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129
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Strikoudis A, Guillamot M, Aifantis I. Regulation of stem cell function by protein ubiquitylation. EMBO Rep 2014; 15:365-82. [PMID: 24652853 DOI: 10.1002/embr.201338373] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Tissue homeostasis depends largely on the ability to replenish impaired or aged cells. Thus, tissue-resident stem cells need to provide functional progeny throughout the lifetime of an organism. Significant work in the past years has characterized how stem cells integrate signals from their environment to shape regulatory transcriptional networks and chromatin-regulating factors that control stem cell differentiation or maintenance. There is increasing interest in how post-translational modifications, and specifically ubiquitylation, control these crucial decisions. Ubiquitylation modulates the stability and function of important factors that regulate key processes in stem cell behavior. In this review, we analyze the role of ubiquitylation in embryonic stem cells and different adult multipotent stem cell systems and discuss the underlying mechanisms that control the balance between quiescence, self-renewal, and differentiation. We also discuss deregulated processes of ubiquitin-mediated protein degradation that lead to the development of tumor-initiating cells.
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Affiliation(s)
- Alexandros Strikoudis
- Howard Hughes Medical Institute New York University School of Medicine, New York, NY, USA
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130
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Webb AE, Brunet A. FOXO transcription factors: key regulators of cellular quality control. Trends Biochem Sci 2014; 39:159-69. [PMID: 24630600 DOI: 10.1016/j.tibs.2014.02.003] [Citation(s) in RCA: 398] [Impact Index Per Article: 39.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 02/05/2014] [Accepted: 02/07/2014] [Indexed: 12/13/2022]
Abstract
FOXO transcription factors are conserved regulators of longevity downstream of insulin signaling. These transcription factors integrate signals emanating from nutrient deprivation and stress stimuli to coordinate programs of genes involved in cellular metabolism and resistance to oxidative stress. Here, we discuss emerging evidence for a pivotal role of FOXO factors in promoting the expression of genes involved in autophagy and the ubiquitin-proteasome system--two cell clearance processes that are essential for maintaining organelle and protein homeostasis (proteostasis). The ability of FOXO to maintain cellular quality control appears to be critical in processes and pathologies where damaged proteins and organelles accumulate, including aging and neurodegenerative diseases.
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Affiliation(s)
- Ashley E Webb
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Anne Brunet
- Department of Genetics, Stanford University, Stanford, CA 94305, USA; Glenn Laboratories for the Biology of Aging at Stanford, Stanford, CA 94305, USA.
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131
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Translational regulator eIF2α in tumor. Tumour Biol 2014; 35:6255-64. [DOI: 10.1007/s13277-014-1789-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 02/21/2014] [Indexed: 11/29/2022] Open
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132
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Lu S, Yan D, Wu Z, Jiang T, Chen J, Yuan L, Lin J, Peng Z, Tang H. Ubiquitin-like with PHD and ring finger domains 2 is a predictor of survival and a potential therapeutic target in colon cancer. Oncol Rep 2014; 31:1802-10. [PMID: 24573556 DOI: 10.3892/or.2014.3035] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 01/29/2014] [Indexed: 11/06/2022] Open
Abstract
In the present study, we investigated the expression of ubiquitin-like with PHD and ring finger domains 2 (UHRF2) in colon cancer and adjacent normal tissues and estimated the clinicopathological significance and predictive value of UHRF2 expression in colon cancer. Using quantitative real-time PCR, tissue microarray (TMA), western blot analysis and immunohistochemical staining, we evaluated UHRF2 mRNA and protein levels in tumor tissues and paired adjacent normal epithelium. We found that UHRF2 was upregulated at both the transcriptional and translational levels in tumor tissues. Immunohistochemical detection of UHRF2 on a TMA containing 203 paired specimens showed that increased cytoplasmic UHRF2 was significantly associated with clinical stage, depth of invasion, nodal involvement, tumor histologic grade and the presence of metastasis. Patients with UHRF2-positive tumors had a much lower disease-free survival [hazard ratio (HR) 9.511, P<0.001] and overall survival (HR 9.820, P<0.001). Univariate and multivariate analyses were performed to determine the correlation between these parameters and the clinical and pathological variables of the study population verifying that UHRF2 immunoreactivity emerged as an independent prognostic factor in the multivariate analysis. UHRF2 may contribute to the progression of colon carcinogenesis and function as a novel prognostic indicator after curative operation.
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Affiliation(s)
- Su Lu
- Department of Pathology, Shanghai Jiaotong University Affiliated First People's Hospital, Shanghai 200080, P.R. China
| | - Dongwang Yan
- Department of General Surgery, Shanghai Jiaotong University Affiliated First People's Hospital, Shanghai 200080, P.R. China
| | - Zehua Wu
- Department of General Surgery, Shanghai Jiaotong University Affiliated First People's Hospital, Shanghai 200080, P.R. China
| | - Tao Jiang
- Department of General Surgery, Shanghai Jiaotong University Affiliated First People's Hospital, Shanghai 200080, P.R. China
| | - Jian Chen
- Department of General Surgery, Shanghai Jiaotong University Affiliated First People's Hospital, Shanghai 200080, P.R. China
| | - Lin Yuan
- Department of Pathology, Shanghai Jiaotong University Affiliated First People's Hospital, Shanghai 200080, P.R. China
| | - Jun Lin
- Department of Pathology, Shanghai Jiaotong University Affiliated First People's Hospital, Shanghai 200080, P.R. China
| | - Zhihai Peng
- Department of General Surgery, Shanghai Jiaotong University Affiliated First People's Hospital, Shanghai 200080, P.R. China
| | - Huamei Tang
- Department of Pathology, Shanghai Jiaotong University Affiliated First People's Hospital, Shanghai 200080, P.R. China
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133
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Peng Z, Maxwell DS, Sun D, Bhanu Prasad BA, Schuber PT, Pal A, Ying Y, Han D, Gao L, Wang S, Levitzki A, Kapuria V, Talpaz M, Young M, Showalter HD, Donato NJ, Bornmann WG. Degrasyn-like symmetrical compounds: possible therapeutic agents for multiple myeloma (MM-I). Bioorg Med Chem 2014; 22:1450-8. [PMID: 24457091 DOI: 10.1016/j.bmc.2013.12.048] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 12/11/2013] [Accepted: 12/21/2013] [Indexed: 12/13/2022]
Abstract
A series of degrasyn-like symmetrical compounds have been designed, synthesized, and screened against B cell malignancy (multiple myeloma, mantle cell lymphoma) cell lines. The lead compounds T5165804 and CP2005 showed higher nanomolar potency against these tumor cells in comparison to degrasyn and inhibited Usp9x activity in vitro and in intact cells. These observations suggest that this new class of compounds holds promise as cancer therapeutic agents.
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Affiliation(s)
- Zhenghong Peng
- Department of Experimental Therapeutics, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States
| | - David S Maxwell
- Department of Experimental Therapeutics, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States
| | - Duoli Sun
- Department of Experimental Therapeutics, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States
| | - Basvoju A Bhanu Prasad
- Department of Experimental Therapeutics, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States
| | - Paul T Schuber
- Department of Experimental Therapeutics, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States
| | - Ashutosh Pal
- Department of Experimental Diagnostic Imaging, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States
| | - Yunming Ying
- Department of Experimental Diagnostic Imaging, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States
| | - Dongmei Han
- Department of Experimental Diagnostic Imaging, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States
| | - Liwei Gao
- Department of Experimental Diagnostic Imaging, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States
| | - Shimei Wang
- Department of Experimental Diagnostic Imaging, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States
| | - Alexander Levitzki
- Unit of Cellular Signaling, Department of Biological Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Vaibhav Kapuria
- Department of Internal Medicine/Division of Hematology/Oncology, University of Michigan School of Medicine, Comprehensive Cancer Center, United States
| | - Moshe Talpaz
- Department of Internal Medicine/Division of Hematology/Oncology, University of Michigan School of Medicine, Comprehensive Cancer Center, United States
| | - Matthew Young
- Department of Pharmacology, University of Michigan School of Medicine, Comprehensive Cancer Center, United States
| | - Hollis D Showalter
- Department of Medicinal Chemistry, University of Michigan College of Pharmacy, Ann Arbor, MI 48109, United States
| | - Nicholas J Donato
- Department of Internal Medicine/Division of Hematology/Oncology, University of Michigan School of Medicine, Comprehensive Cancer Center, United States
| | - William G Bornmann
- Department of Experimental Therapeutics, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States.
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134
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Tripp RA, Mark Tompkins S. Antiviral effects of inhibiting host gene expression. Curr Top Microbiol Immunol 2014; 386:459-77. [PMID: 25007848 DOI: 10.1007/82_2014_409] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
RNA interference (RNAi) has been used to probe the virus-host interface to understand the requirements for host-gene expression needed for virus replication. The availability of arrayed siRNA libraries has enabled a genome-scale, high-throughput analysis of gene pathways usurped for virus replication. Results from these and related screens have led to the discovery of new host factors that regulate virus replication. While effective delivery continues to limit development of RNAi-based drugs, RNAi-based genome discovery has led to identification of druggable targets. These validated targets enable rational development of novel antiviral drugs, including the rescue and repurposing of existing, approved drugs. Existing drugs with known cytotoxicity and mechanisms of action can potentially be re-targeted to regulate host genes and gene products needed by influenza to replicate. Drug repositioning is more cost-effective, less time-consuming, and more effective for anti-influenza virus drug discovery than traditional methods. In this chapter, a general overview of RNAi screening methods, host-gene discovery, and drug repurposing is examined with emphasis on utilizing RNAi to identify druggable genes that can be targeted for drug development or repurposing.
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Affiliation(s)
- Ralph A Tripp
- Department of Infectious Disease, University of Georgia, Athens, GA, 30602, USA,
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135
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Shen J, Song G, An M, Li X, Wu N, Ruan K, Hu J, Hu R. The use of hollow mesoporous silica nanospheres to encapsulate bortezomib and improve efficacy for non-small cell lung cancer therapy. Biomaterials 2014; 35:316-26. [DOI: 10.1016/j.biomaterials.2013.09.098] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 09/25/2013] [Indexed: 01/13/2023]
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136
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MDM2 SNP309 is an ethnicity-dependent risk factor for digestive tract cancers. Tumour Biol 2013; 35:3431-8. [PMID: 24338709 DOI: 10.1007/s13277-013-1453-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 11/19/2013] [Indexed: 01/10/2023] Open
Abstract
Published data on the relationship between T309G polymorphism in the murine double minute 2 (MDM2) gene and susceptibility of digestive tract cancers (DTC) are inconclusive. Thus, the aim of this study is to determine whether MDM2 T309G polymorphism is associated with the risk of diverse DTC, including esophagus, stomach, liver, bile duct, pancreas, and colorectum cancers. Relevant studies were identified up to October 1, 2013. Crude odds ratio (OR) and 95% confidence interval (CI) were used as a measure of the strength of the association. The pooled result based on all studies showed that there was a statistically significant link between MDM2 T309G polymorphism and DTC susceptibility (T vs. G: OR = 0.82, 95%CI = 0.76-0.88). When stratified by race, significant associations were observed for all genetic models among Asians (especially in Chinese population), but not among Caucasians. Subgroup analyses according to tumor location indicated that the genetic variant was associated with esophageal (OR = 0.88, 95%CI = 0.81-0.96 for T vs. G), hepatocellular (OR = 0.69, 95%CI = 0.57-0.84 for T vs. G) and pancreatic cancer risk but not associated with cholangiocarcinoma or colorectum cancer susceptibility. Meanwhile, the G allele was also suggested to be associated with increased gastric cancer risk (OR = 0.68, 95%CI = 0.54-0.87 for TT + TG vs. GG for intestinal type of gastric cancer and OR = 0.18, 95%CI = 0.06-0.50 for TT vs. GG for Helicobacter pylori infection positive stomach cancer). Our study indicates that the MDM2 T309G polymorphism may be an ethnicity-dependent risk factor for DTC, especially for the upper gastrointestinal tract malignancies.
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Till SJ, Raynsford EJ, Reynolds CJ, Quigley KJ, Grzybowska-Kowalczyk A, Saggar LR, Goldstone A, Maillere B, Kwok WW, Altmann DM, Durham SR, Boyton RJ. Peptide-induced immune regulation by a promiscuous and immunodominant CD4T-cell epitope of Timothy grass pollen: a role of Cbl-b and Itch in regulation. Thorax 2013; 69:335-45. [PMID: 24258832 DOI: 10.1136/thoraxjnl-2013-204324] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND T-cell targeted peptide epitope tolerogens from grass pollen allergens may be useful in treating seasonal allergic rhinitis, but there is urgent need for optimisation of approaches from improved understanding of mechanism. OBJECTIVE We sought to identify human leukocyte antigen (HLA)-DR1-restricted epitopes from the Timothy grass pollen allergen, Phleum pratense, and characterise T-cell immune regulation following intranasal administration of a single, immunodominant epitope. METHODS T-cell epitopes within P pratense were identified using HLA-DR1 transgenic mice and tetramer-guided epitope mapping (TGEM) in HLA-DR1-positive individuals with grass allergy. An immunodominant epitope was tested in HLA-DR1 transgenics for impact on responses to whole Phl p5 b or peptide. Microarrays and quantitative PCR were used to characterise T-cell immunity. RESULTS Peptide 26 (p26) was identified in HLA-DR1 transgenic mice and by TGEM analysis of HLA-DR1-positive individuals with grass allergy. p26 shows promiscuous binding to a wide range of HLA class II alleles, making it of relevance across immunogenetically diverse patients. The epitope is conserved in rye and velvet grass, making it applicable across a spectrum of grass pollen allergy. Intranasal pretreatment of mice with p26 results in significantly reduced T-cell responses. Transcriptomic array analysis in mice showed T-cell regulation in the intranasal treatment group associated with increased expression of members of the Cbl-b and Itch E3 ubiquitin ligase pathway. CONCLUSIONS We defined an immunodominant P pratense epitope, p26, with broad binding across multiple HLA class II alleles. Intranasal treatment of mice with p26 results in T-cell regulation to whole allergen, involving the Cbl-b and Itch regulatory pathway.
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Affiliation(s)
- Stephen J Till
- Department of Asthma, Allergy and Respiratory Science, Division of Asthma, Allergy & Lung Biology, MRC & Asthma UK Centre in Allergic Mechanisms of Asthma, King's College London, , London, UK
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Zhu S, Yao F, Li WH, Wan JN, Zhang YM, Tang Z, Khan S, Wang CH, Sun SR. PKCδ-dependent Activation of the Ubiquitin Proteasome System is Responsible for High Glucose-induced Human Breast Cancer MCF-7 Cell Proliferation, Migration and Invasion. Asian Pac J Cancer Prev 2013; 14:5687-92. [DOI: 10.7314/apjcp.2013.14.10.5687] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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139
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Wang H, Li P, Zhao B. Knockdown of NOB1 expression by RNAi inhibits cellular proliferation and migration in human gliomas. Gene 2013; 528:146-53. [DOI: 10.1016/j.gene.2013.07.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 07/02/2013] [Accepted: 07/08/2013] [Indexed: 01/27/2023]
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Hobbs GA, Gunawardena HP, Baker R, Campbell SL. Site-specific monoubiquitination activates Ras by impeding GTPase-activating protein function. Small GTPases 2013; 4:186-92. [PMID: 24030601 DOI: 10.4161/sgtp.26270] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
KRas has recently been shown to be activated by monoubiquitination (mUb). Similar to oncogenic mutations, mUb of Ras at position 147 activates Ras by causing a defect in GTPase activating protein (GAP) function. To characterize the mechanism by which mUb impairs GAP-mediated downregulation of Ras, we made various modifications at position 147 of Ras and examined the impact on Ras sensitivity to GAP function. Whereas small modifications (iodoacetamide and glutathione) at position 147 of Ras do not affect GAP-mediated hydrolysis, ligation of Ras to Ub(G76C) (native linker), Ub(X77C) (one residue longer), and PDZ2 (with a native ubiquitin linker) was defective in GAP-mediated GTP hydrolysis. However, restoration of GAP activity was observed for Ras modified with the PDZ2 domain containing a shorter and stiffer linker region than ubiquitin. Therefore, the properties of the linker region dictate whether modification affects GAP-mediated hydrolysis, and our data indicate that the GAP defect requires a minimum linker length of 7 to 8 residues.
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Affiliation(s)
- G Aaron Hobbs
- Department of Biochemistry and Biophysics; University of North Carolina; Chapel Hill, NC USA
| | - Harsha P Gunawardena
- Department of Biochemistry and Biophysics; University of North Carolina; Chapel Hill, NC USA
| | - Rachael Baker
- Department of Biochemistry and Biophysics; University of North Carolina; Chapel Hill, NC USA
| | - Sharon L Campbell
- Department of Biochemistry and Biophysics; University of North Carolina; Chapel Hill, NC USA; Lineberger Comprehensive Cancer Center; University of North Carolina; Chapel Hill, NC USA
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141
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Goard CA, Schimmer AD. Mitochondrial matrix proteases as novel therapeutic targets in malignancy. Oncogene 2013; 33:2690-9. [PMID: 23770858 DOI: 10.1038/onc.2013.228] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 04/23/2013] [Accepted: 04/30/2013] [Indexed: 12/30/2022]
Abstract
Although mitochondrial function is often altered in cancer, it remains essential for tumor viability. Tight control of protein homeostasis is required for the maintenance of mitochondrial function, and the mitochondrial matrix houses several coordinated protein quality control systems. These include three evolutionarily conserved proteases of the AAA+ superfamily-the Lon, ClpXP and m-AAA proteases. In humans, these proteases are proposed to degrade, process and chaperone the assembly of mitochondrial proteins in the matrix and inner membrane involved in oxidative phosphorylation, mitochondrial protein synthesis, mitochondrial network dynamics and nucleoid function. In addition, these proteases are upregulated by a variety of mitochondrial stressors, including oxidative stress, unfolded protein stress and imbalances in respiratory complex assembly. Given that tumor cells must survive and proliferate under dynamic cellular stress conditions, dysregulation of mitochondrial protein quality control systems may provide a selective advantage. The association of mitochondrial matrix AAA+ proteases with cancer and their potential for therapeutic modulation therefore warrant further consideration. Although our current knowledge of the endogenous human substrates of these proteases is limited, we highlight functional insights gained from cultured human cells, protease-deficient mouse models and other eukaryotic model organisms. We also review the consequences of disrupting mitochondrial matrix AAA+ proteases through genetic and pharmacological approaches, along with implications of these studies on the potential of these proteases as anticancer therapeutic targets.
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Affiliation(s)
- C A Goard
- Princess Margaret Cancer Centre, Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada
| | - A D Schimmer
- Princess Margaret Cancer Centre, Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada
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Correctors of the basic trafficking defect of the mutant F508del-CFTR that causes cystic fibrosis. Curr Opin Chem Biol 2013; 17:353-60. [DOI: 10.1016/j.cbpa.2013.04.020] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 04/16/2013] [Accepted: 04/18/2013] [Indexed: 01/01/2023]
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143
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Majetschak M. Regulation of the proteasome by ATP: implications for ischemic myocardial injury and donor heart preservation. Am J Physiol Heart Circ Physiol 2013; 305:H267-78. [PMID: 23709597 DOI: 10.1152/ajpheart.00206.2012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Several lines of evidence suggest that proteasomes are involved in multiple aspects of myocardial physiology and pathology, including myocardial ischemia-reperfusion injury. It is well established that the 26S proteasome is an ATP-dependent enzyme and that ischemic heart disease is associated with changes in the ATP content of the cardiomyocyte. A functional link between the 26S proteasome, myocardial ATP concentrations, and ischemic cardiac injury, however, has been suggested only recently. This review discusses the currently available data on the pathophysiological role of the cardiac proteasome during ischemia and reperfusion in the context of the cellular ATP content. Depletion of the myocardial ATP content during ischemia appears to activate the 26S proteasome via direct regulatory effects of ATP on 26S proteasome stability and activity. This implies pathological degradation of target proteins by the proteasome and could provide a pathophysiological basis for beneficial effects of proteasome inhibitors in various models of myocardial ischemia. In contrast to that in the ischemic heart, reduced and impaired proteasome activity is detectable in the postischemic heart. The paradoxical findings that proteasome inhibitors showed beneficial effects when administered during reperfusion in some studies could be explained by their anti-inflammatory and immune suppressive actions, leading to reduction of leukocyte-mediated myocardial reperfusion injury. The direct regulatory effects of ATP on the 26S proteasome have implications for the understanding of the contribution of the 26S proteasome to the pathophysiology of the ischemic heart and its possible role as a therapeutic target.
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Affiliation(s)
- Matthias Majetschak
- Departments of Surgery and Molecular Pharmacology and Therapeutics, Loyola University Chicago, Maywood, IL 60153, USA.
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