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Mishra AP, Salehi B, Sharifi-Rad M, Pezzani R, Kobarfard F, Sharifi-Rad J, Nigam M. Programmed Cell Death, from a Cancer Perspective: An Overview. Mol Diagn Ther 2018; 22:281-295. [PMID: 29560608 DOI: 10.1007/s40291-018-0329-9] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Programmed cell death (PCD) is probably the most widely discussed subject among the topics of cancer therapy. Over the last 2 decades an astonishing boost in our perception of cell death has been seen, and its role in cancer and cancer therapy has been thoroughly investigated. A number of discoveries have clarified the molecular mechanism of PCD, thus expounding the link between PCD and therapeutic tools. Even though PCD is assumed to play a major role in anticancer therapy, the clinical relevance of its induction remains uncertain. Since PCD involves multiple death programs including programmed necrosis and autophagic cell death, it has contributed to our better understanding of cancer pathogenesis and therapeutics. In this review, we discuss a brief outline of PCD types as well as their role in cancer therapeutics. Since irregularities in the cell death process are frequently found in various cancers, key proteins governing cell death type could be used as therapeutic targets for a wide range of cancer.
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Affiliation(s)
- Abhay P Mishra
- Department of Pharmaceutical Chemistry, H. N. B. Garhwal (A Central) University, Srinagar Garhwal, Uttarakhand, 246174, India
| | - Bahare Salehi
- Medical Ethics and Law Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mehdi Sharifi-Rad
- Department of Medical Parasitology, Zabol University of Medical Sciences, Zabol, 61663335, Iran
| | - Raffaele Pezzani
- OU Endocrinology, Dept. Medicine (DIMED), University of Padova, via Ospedale 105, 35128, Padua, Italy.,AIROB, Associazione Italiana per la Ricerca Oncologica di Base, Padua, Italy
| | - Farzad Kobarfard
- Phytochemistry Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Department of Medicinal Chemistry, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Javad Sharifi-Rad
- Phytochemistry Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. .,Department of Chemistry, Richardson College for the Environmental Science Complex, The University of Winnipeg, Winnipeg, MB, Canada.
| | - Manisha Nigam
- Department of Biochemistry, H. N. B. Garhwal (A Central) University, Srinagar Garhwal, Uttarakhand, 246174, India.
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Rogers-Broadway KR, Kumar J, Sisu C, Wander G, Mazey E, Jeyaneethi J, Pados G, Tsolakidis D, Klonos E, Grunt T, Hall M, Chatterjee J, Karteris E. Differential expression of mTOR components in endometriosis and ovarian cancer: Effects of rapalogues and dual kinase inhibitors on mTORC1 and mTORC2 stoichiometry. Int J Mol Med 2018; 43:47-56. [PMID: 30387804 PMCID: PMC6257843 DOI: 10.3892/ijmm.2018.3967] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 09/04/2018] [Indexed: 01/22/2023] Open
Abstract
Endometriosis is a well‑known risk factor for ovarian cancer. The genetic changes that characterise endometriosis are poorly understood; however, the mechanistic target of rapamycin (mTOR) pathway is involved. In this study, we investigated the expression of key mTOR components in endometriosis and the effects of rapalogues using an endometrioid ovarian carcinoma cell line (MDAH 2774) as an in vitro model. Gene expression of mTOR, DEPTOR, Rictor and Raptor was assessed by qPCR in 24 endometriosis patients and in silico in ovarian cancer patients. Furthermore, the effects of Rapamycin, Everolimus, Deforolimus, Temsirolimus, Resveratrol, and BEZ235 (Dactolisib, a dual kinase inhibitor) on mTOR signalling components was assessed. mTOR showed a significant increase in the expression in endometriosis and ovarian endometrioid adenocarcinoma patients compared to non‑affected controls. DEPTOR, an inhibitor of mTOR, was downregulated in the advanced stages of ovarian cancer (III and IV) compared to earlier stages (I and II). Treatment of MDAH‑2774 cells with the mTOR inhibitors resulted in the significant upregulation of DEPTOR mRNA, whereas treatment with rapamycin and BEZ‑235 (100 nM) resulted in downregulation of the mTOR protein expression after 48 h of treatment. None of the treatments resulted in translocation of mTOR from cytoplasm to nucleus. Upregulation of DEPTOR is a positive prognostic marker in ovarian cancer and is increased in response to mTOR pathway inhibition suggesting that it functions as a tumour suppressor gene in endometrioid ovarian carcinoma. Collectively, our data suggest the mTOR pathway as a potential connection between endometriosis and ovarian cancer and may be a potential target in the treatment of both conditions.
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Affiliation(s)
- Karly-Rai Rogers-Broadway
- Division of Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge UB8 3PH, UK
| | - Juhi Kumar
- Division of Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge UB8 3PH, UK
| | - Cristina Sisu
- Division of Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge UB8 3PH, UK
| | | | - Emily Mazey
- Division of Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge UB8 3PH, UK
| | - Jeyarooban Jeyaneethi
- Division of Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge UB8 3PH, UK
| | - George Pados
- First Department of OB‑GYN, 'Papageorgiou' Hospital, University of Thessaloniki Medical School, Thessaloniki 54124, Greece
| | - Dimitris Tsolakidis
- First Department of OB‑GYN, 'Papageorgiou' Hospital, University of Thessaloniki Medical School, Thessaloniki 54124, Greece
| | - Eleftherios Klonos
- First Department of OB‑GYN, 'Papageorgiou' Hospital, University of Thessaloniki Medical School, Thessaloniki 54124, Greece
| | - Thomas Grunt
- Ludwig Boltzmann Cluster Oncology and Division of Oncology, Department of Medicine I, Medical University Vienna, A‑1090 Vienna, Austria
| | - Marcia Hall
- Division of Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge UB8 3PH, UK
| | - Jayanta Chatterjee
- Faculty of Health and Medical Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey GU2 7XH, UK
| | - Emmanouil Karteris
- Division of Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge UB8 3PH, UK
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Guo X, He D, Zhang E, Chen J, Chen Q, Li Y, Yang L, Yang Y, Zhao Y, Wang G, He J, Cai Z. HMGB1 knockdown increases MM cell vulnerability by regulating autophagy and DNA damage repair. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2018; 37:205. [PMID: 30157958 PMCID: PMC6114506 DOI: 10.1186/s13046-018-0883-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 08/16/2018] [Indexed: 02/06/2023]
Abstract
Background With the development of novel therapeutic agents, the survival of multiple myeloma (MM) patients has much improved. However, the disease is incurable due to drug resistance. Previous studies have found that high-mobility group box 1 (HMGB1) is involved in inflammation, angiogenesis, DNA damage repair, and cancer invasion, progression, metastasis and drug resistance and that high HMGB1 expression is associated with poor MM prognosis, yet the role and mechanism of HMGB1 in MM remains unclear. Methods Through gene expression and Oncomine database analyses, we found that HMGB1 is associated with a poor prognosis in MM patients. RNA interference together with gene array analysis, cell proliferation and apoptosis assays, autophagy detection assays, western blotting, and in vivo xenograft models were employed to evaluate the effect of HMGB1 and the mechanism involved in MM drug resistance. Results MM cell lines and primary MM samples were found to express high levels of HMGB1, which was negatively associated with the 3-year survival of MM patients. HMGB1 knockdown in MM cells enhanced the inhibitory effect of chemotherapy with dexamethasone (Dex) via apoptosis induction. Furthermore, downregulation of HMGB1 activated the mTOR pathway, inhibited autophagy and increased DNA damage induced by Dex by modulating expression of related genes. In vivo, xenograft models showed that after Dex treatment, the tumor burden of HMGB1-knockdown mice was decreased compared with that of control mice. Conclusions Our research shows that HMGB1 participates in autophagy and DNA damage repair and that downregulation of HMGB1 enhances the sensitivity of MM cells to Dex, suggesting that HMGB1 may serve as a target for MM treatment.
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Affiliation(s)
- Xing Guo
- Bone Marrow Transplantation Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, Zhejiang, China
| | - Donghua He
- Bone Marrow Transplantation Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, Zhejiang, China
| | - Enfan Zhang
- Bone Marrow Transplantation Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, Zhejiang, China
| | - Jing Chen
- Bone Marrow Transplantation Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, Zhejiang, China
| | - Qingxiao Chen
- Bone Marrow Transplantation Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, Zhejiang, China
| | - Yi Li
- Bone Marrow Transplantation Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, Zhejiang, China
| | - Li Yang
- Bone Marrow Transplantation Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, Zhejiang, China
| | - Yang Yang
- Bone Marrow Transplantation Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, Zhejiang, China
| | - Yi Zhao
- Bone Marrow Transplantation Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, Zhejiang, China
| | - Gang Wang
- Quzhou People's Hospital, Quzhou, 324000, Zhejiang, China
| | - Jingsong He
- Bone Marrow Transplantation Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, Zhejiang, China
| | - Zhen Cai
- Bone Marrow Transplantation Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, Zhejiang, China.
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Hu B, Shi D, Lv X, Wu F, Chen S, Shao Z. Prognostic and clinicopathological significance of DEPTOR expression in cancer patients: a meta-analysis. Onco Targets Ther 2018; 11:5083-5092. [PMID: 30174446 PMCID: PMC6110285 DOI: 10.2147/ott.s167355] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Background DEP domain containing mammalian target of rapamycin (mTOR)-interacting protein (DEPTOR), a recently discovered endogenous inhibitor of mTOR, has been found to be abnormally expressed in various tumors. Recent studies have demonstrated that DEPTOR could serve as a potential prognostic biomarker in several kinds of cancer. However, the prognostic value of DEPTOR is still controversial so far. Patients and methods PubMed, Embase and Web of Science were systematically searched to obtain all relevant articles about the prognostic value of DEPTOR in cancer patients. ORs or HRs with corresponding 95% CIs were pooled to estimate the association between DEP-TOR expression and the clinicopathological characteristics or survival of cancer patients. Results A total of nine eligible studies with 974 cancer patients were included in our meta-analysis. Our results demonstrated that the expression of DEPTOR was not associated with the overall survival (OS) (pooled HR=0.795, 95% CI=0.252-2.509) and event-free survival (EFS) (pooled HR=1.244, 95% CI=0.543-2.848) in cancer patients. Furthermore, subgroup analysis divided by sample size, type of cancer, Newcastle-Ottawa Scale (NOS) score and evaluation of DEPTOR expression showed identical prognostic value. In addition, our analysis also revealed that there was no significant association between expression level of DEPTOR and clinicopathological characteristics, such as tumor stage, lymph node metastasis, differentiation grade and gender. Conclusion Our meta-analysis suggested that despite the fact that DEPTOR could be overexpressed or downregulated in cancer patients, it might not be a potential marker to predict the prognosis of cancer patients.
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Affiliation(s)
- Binwu Hu
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China,
| | - Deyao Shi
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China,
| | - Xiao Lv
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China,
| | - Fashuai Wu
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China,
| | - Songfeng Chen
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Zengwu Shao
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China,
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Chen S, Jia L, Zhang S, Zheng Y, Zhou Y. DEPTOR regulates osteogenic differentiation via inhibiting MEG3-mediated activation of BMP4 signaling and is involved in osteoporosis. Stem Cell Res Ther 2018; 9:185. [PMID: 29973283 PMCID: PMC6033203 DOI: 10.1186/s13287-018-0935-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 05/02/2018] [Accepted: 06/18/2018] [Indexed: 02/07/2023] Open
Abstract
Background The mammalian target of rapamycin (mTOR) pathway plays a significant role in osteogenic differentiation and bone maintenance. As the only known endogenous inhibitor of mTOR function, DEP domain containing mTOR interacting protein (DEPTOR) is potentially involved in stem cell differentiation, although the pathophysiological significance and its molecular mechanisms remain unclear. The present study aimed to elucidate the effects of DEPTOR on the progress of osteoporosis and investigate the underlying molecular mechanisms of osteogenic regulation. Methods An ovariectomy mouse model with decreased bone formation and osteogenic induction with bone marrow mesenchymal stem cells (BMSCs) were used to investigate the relationship between DEPTOR and osteogenic events. A loss-of-function investigation was then performed to explore the role of DEPTOR in the osteogenic differentiation of BMSCs both in vitro and in vivo. Finally, long noncoding RNA (lncRNA) and mRNA sequences were investigated to reveal the underlying mechanisms of DEPTOR in osteogenic regulation. RNA interference, western blotting, and chromatin immunoprecipitation assays were performed for further mechanistic determination. Results The results indicated that DEPTOR contributes to the progress of osteoporosis, and higher expression of Deptor was observed in osteoporotic bones. The expression of DEPTOR was reduced during the osteogenic differentiation of BMSCs, and knockdown of DEPTOR promoted BMSC osteogenesis in vitro and in vivo. lncRNA and mRNA sequences indicated that knockdown of DEPTOR upregulated the expression of maternally expressed 3 (nonprotein coding) (MEG3), which subsequently activated bone morphogenetic protein 4 (BMP4) signaling. Furthermore, DEPTOR could bind to a specific region (− 1000 bp ~ 0) of the MEG3 promoter to regulate its transcription, and inhibition of MEG3 reduced BMP4 activation triggered by DEPTOR knockdown. Conclusions Taken together, our study revealed a novel function of DEPTOR in osteogenic differentiation by inhibiting MEG3-mediated activation of BMP4 signaling, which suggested that DEPTOR could be a therapeutic target for bone loss diseases and skeletal tissue regeneration. Electronic supplementary material The online version of this article (10.1186/s13287-018-0935-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Si Chen
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China
| | - Lingfei Jia
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China.,Central Laboratory, Peking University School and Hospital of Stomatology, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China.,National Clinical Research Center for Oral Diseases, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China
| | - Shan Zhang
- Central Laboratory, Peking University School and Hospital of Stomatology, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China
| | - Yunfei Zheng
- Department of Orthodontics, Peking University School and Hospital of Stomatology, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China. .,National Clinical Research Center for Oral Diseases, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China.
| | - Yongsheng Zhou
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China. .,National Engineering Lab for Digital and Material Technology of Stomatology, Peking University School and Hospital of Stomatology, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China. .,National Clinical Research Center for Oral Diseases, 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China.
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Wang C, Dai H, Xiong Z, Song Q, Zou Z, Li M, Nie J, Bai X, Chen Z. Loss of DEPTOR in renal tubules protects against cisplatin-induced acute kidney injury. Cell Death Dis 2018; 9:441. [PMID: 29670094 PMCID: PMC5906659 DOI: 10.1038/s41419-018-0483-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 02/21/2018] [Accepted: 03/13/2018] [Indexed: 12/30/2022]
Abstract
DEP domain containing mTOR-interacting protein (DEPTOR) was originally identified as an in vivo dual inhibitor of mechanistic target of rapamycin (mTOR). It was recently reported to be involved in renal physiology and pathology in vitro; however, its detailed roles and mechanisms in vivo are completely unknown. We observed that DEPTOR expression in the kidney was markedly increased on day 3 after cisplatin treatment, at which time cell apoptosis peaked, implicating DEPTOR in cisplatin-induced acute kidney injury (AKI). We then used the Cre–LoxP system to generate mutant mice in which the DEPTOR gene was specifically deleted in the proximal tubule cells. DEPTOR deficiency did not alter the renal histology or functions in the saline-treated group, indicating that DEPTOR is not essential for kidney function under physiological conditions. Interestingly, DEPTOR deletion extensively preserved the renal histology and maintained the kidney functions after cisplatin treatment, suggesting that the absence of DEPTOR ameliorates cisplatin-induced AKI. Mechanistically, DEPTOR modulated p38 MAPK signaling and TNFα production in vivo and in vitro, rather than mTOR signaling, thus moderating the inflammatory response and cell apoptosis induced by cisplatin. Collectively, our findings demonstrate the roles and mechanisms of DEPTOR in the regulation of the renal physiology and pathology, and demonstrate that the loss of DEPTOR in the proximal tubules protects against cisplatin-induced AKI.
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Affiliation(s)
- Caixia Wang
- The State Key Laboratory of Organ Failure Research, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Huaiqian Dai
- The State Key Laboratory of Organ Failure Research, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Zhi Xiong
- The State Key Laboratory of Organ Failure Research, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Qiancheng Song
- The State Key Laboratory of Organ Failure Research, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Zhipeng Zou
- The State Key Laboratory of Organ Failure Research, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Mangmang Li
- The State Key Laboratory of Organ Failure Research, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Jing Nie
- The State Key Laboratory of Organ Failure Research, Department of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Xiaochun Bai
- The State Key Laboratory of Organ Failure Research, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China.
| | - Zhenguo Chen
- The State Key Laboratory of Organ Failure Research, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China.
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Perez-Alvarez MJ, Villa Gonzalez M, Benito-Cuesta I, Wandosell FG. Role of mTORC1 Controlling Proteostasis after Brain Ischemia. Front Neurosci 2018; 12:60. [PMID: 29497356 PMCID: PMC5818460 DOI: 10.3389/fnins.2018.00060] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 01/24/2018] [Indexed: 01/24/2023] Open
Abstract
Intense efforts are being undertaken to understand the pathophysiological mechanisms triggered after brain ischemia and to develop effective pharmacological treatments. However, the underlying molecular mechanisms are complex and not completely understood. One of the main problems is the fact that the ischemic damage is time-dependent and ranges from negligible to massive, involving different cell types such as neurons, astrocytes, microglia, endothelial cells, and some blood-derived cells (neutrophils, lymphocytes, etc.). Thus, approaching such a complicated cellular response generates a more complex combination of molecular mechanisms, in which cell death, cellular damage, stress and repair are intermixed. For this reason, animal and cellular model systems are needed in order to dissect and clarify which molecular mechanisms have to be promoted and/or blocked. Brain ischemia may be analyzed from two different perspectives: that of oxygen deprivation (hypoxic damage per se) and that of deprivation of glucose/serum factors. For investigations of ischemic stroke, middle cerebral artery occlusion (MCAO) is the preferred in vivo model, and uses two different approaches: transient (tMCAO), where reperfusion is permitted; or permanent (pMCAO). As a complement to this model, many laboratories expose different primary cortical neuron or neuronal cell lines to oxygen-glucose deprivation (OGD). This ex vivo model permits the analysis of the impact of hypoxic damage and the specific response of different cell types implicated in vivo, such as neurons, glia or endothelial cells. Using in vivo and neuronal OGD models, it was recently established that mTORC1 (mammalian Target of Rapamycin Complex-1), a protein complex downstream of PI3K-Akt pathway, is one of the players deregulated after ischemia and OGD. In addition, neuroprotective intervention either by estradiol or by specific AT2R agonists shows an important regulatory role for the mTORC1 activity, for instance regulating vascular endothelial growth factor (VEGF) levels. This evidence highlights the importance of understanding the role of mTORC1 in neuronal death/survival processes, as it could be a potential therapeutic target. This review summarizes the state-of-the-art of the complex kinase mTORC1 focusing in upstream and downstream pathways, their role in central nervous system and their relationship with autophagy, apoptosis and neuroprotection/neurodegeneration after ischemia/hypoxia.
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Affiliation(s)
- Maria J Perez-Alvarez
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Madrid, Spain.,Departamento de Biología (Fisiología Animal), Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, Spain.,Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas, Madrid, Spain
| | - Mario Villa Gonzalez
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Madrid, Spain.,Departamento de Biología (Fisiología Animal), Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, Spain
| | - Irene Benito-Cuesta
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Madrid, Spain.,Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas, Madrid, Spain
| | - Francisco G Wandosell
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Madrid, Spain.,Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas, Madrid, Spain
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Varusai TM, Nguyen LK. Dynamic modelling of the mTOR signalling network reveals complex emergent behaviours conferred by DEPTOR. Sci Rep 2018; 8:643. [PMID: 29330362 PMCID: PMC5766521 DOI: 10.1038/s41598-017-18400-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 12/01/2017] [Indexed: 01/10/2023] Open
Abstract
The mechanistic Target of Rapamycin (mTOR) signalling network is an evolutionarily conserved network that controls key cellular processes, including cell growth and metabolism. Consisting of the major kinase complexes mTOR Complex 1 and 2 (mTORC1/2), the mTOR network harbours complex interactions and feedback loops. The DEP domain-containing mTOR-interacting protein (DEPTOR) was recently identified as an endogenous inhibitor of both mTORC1 and 2 through direct interactions, and is in turn degraded by mTORC1/2, adding an extra layer of complexity to the mTOR network. Yet, the dynamic properties of the DEPTOR-mTOR network and the roles of DEPTOR in coordinating mTORC1/2 activation dynamics have not been characterised. Using computational modelling, systems analysis and dynamic simulations we show that DEPTOR confers remarkably rich and complex dynamic behaviours to mTOR signalling, including abrupt, bistable switches, oscillations and co-existing bistable/oscillatory responses. Transitions between these distinct modes of behaviour are enabled by modulating DEPTOR expression alone. We characterise the governing conditions for the observed dynamics by elucidating the network in its vast multi-dimensional parameter space, and develop strategies to identify core network design motifs underlying these dynamics. Our findings provide new systems-level insights into the complexity of mTOR signalling contributed by DEPTOR.
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Affiliation(s)
- Thawfeek M Varusai
- European Bioinformatics Institute, EMBL-EBI, Wellcome Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, UK.,Systems Biology Ireland, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Lan K Nguyen
- Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Victoria, 3800, Australia. .,Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, 3800, Australia. .,Systems Biology Ireland, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland.
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Siu C, Wiseman S, Gakkhar S, Heravi-Moussavi A, Bilenky M, Carles A, Sierocinski T, Tam A, Zhao E, Kasaian K, Moore RA, Mungall AJ, Walker B, Thomson T, Marra MA, Hirst M, Jones SJM. Characterization of the human thyroid epigenome. J Endocrinol 2017; 235:153-165. [PMID: 28808080 DOI: 10.1530/joe-17-0145] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 08/14/2017] [Indexed: 12/15/2022]
Abstract
The thyroid gland, necessary for normal human growth and development, functions as an essential regulator of metabolism by the production and secretion of appropriate levels of thyroid hormone. However, assessment of abnormal thyroid function may be challenging suggesting a more fundamental understanding of normal function is needed. One way to characterize normal gland function is to study the epigenome and resulting transcriptome within its constituent cells. This study generates the first published reference epigenomes for human thyroid from four individuals using ChIP-seq and RNA-seq. We profiled six histone modifications (H3K4me1, H3K4me3, H3K27ac, H3K36me3, H3K9me3, H3K27me3), identified chromatin states using a hidden Markov model, produced a novel quantitative metric for model selection and established epigenomic maps of 19 chromatin states. We found that epigenetic features characterizing promoters and transcription elongation tend to be more consistent than regions characterizing enhancers or Polycomb-repressed regions and that epigenetically active genes consistent across all epigenomes tend to have higher expression than those not marked as epigenetically active in all epigenomes. We also identified a set of 18 genes epigenetically active and consistently expressed in the thyroid that are likely highly relevant to thyroid function. Altogether, these epigenomes represent a powerful resource to develop a deeper understanding of the underlying molecular biology of thyroid function and provide contextual information of thyroid and human epigenomic data for comparison and integration into future studies.
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Affiliation(s)
- Celia Siu
- Canada's Michael Smith Genome Sciences CentreBC Cancer Agency, Vancouver, Canada
- Department of SciencesUniversity of British Columbia, Vancouver, Canada
| | - Sam Wiseman
- Department of SurgerySt. Paul's Hospital & University of British Columbia, Vancouver, Canada
| | - Sitanshu Gakkhar
- Canada's Michael Smith Genome Sciences CentreBC Cancer Agency, Vancouver, Canada
| | | | - Misha Bilenky
- Canada's Michael Smith Genome Sciences CentreBC Cancer Agency, Vancouver, Canada
| | - Annaick Carles
- Department of Microbiology & ImmunologyMichael Smith Laboratories, University of British Columbia, Vancouver, Canada
| | - Thomas Sierocinski
- Department of Microbiology & ImmunologyMichael Smith Laboratories, University of British Columbia, Vancouver, Canada
| | - Angela Tam
- Canada's Michael Smith Genome Sciences CentreBC Cancer Agency, Vancouver, Canada
| | - Eric Zhao
- Canada's Michael Smith Genome Sciences CentreBC Cancer Agency, Vancouver, Canada
| | - Katayoon Kasaian
- Canada's Michael Smith Genome Sciences CentreBC Cancer Agency, Vancouver, Canada
| | - Richard A Moore
- Canada's Michael Smith Genome Sciences CentreBC Cancer Agency, Vancouver, Canada
| | - Andrew J Mungall
- Canada's Michael Smith Genome Sciences CentreBC Cancer Agency, Vancouver, Canada
| | - Blair Walker
- Department of Pathology and Laboratory MedicineSt. Paul's Hospital & University of British Columbia, Vancouver, Canada
| | - Thomas Thomson
- Department of Pathology and Laboratory MedicineBC Cancer Agency & University of British Columbia, Vancouver, Canada
| | - Marco A Marra
- Canada's Michael Smith Genome Sciences CentreBC Cancer Agency, Vancouver, Canada
- Department of Medical GeneticsUniversity of British Columbia, Vancouver, Canada
| | - Martin Hirst
- Canada's Michael Smith Genome Sciences CentreBC Cancer Agency, Vancouver, Canada
- Department of Microbiology & ImmunologyMichael Smith Laboratories, University of British Columbia, Vancouver, Canada
| | - Steven J M Jones
- Canada's Michael Smith Genome Sciences CentreBC Cancer Agency, Vancouver, Canada
- Department of Medical GeneticsUniversity of British Columbia, Vancouver, Canada
- Department of Molecular Biology & BiochemistrySimon Fraser University, Burnaby, Canada
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60
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Hu B, Lv X, Gao F, Chen S, Wang S, Qing X, Liu J, Wang B, Shao Z. Downregulation of DEPTOR inhibits the proliferation, migration, and survival of osteosarcoma through PI3K/Akt/mTOR pathway. Onco Targets Ther 2017; 10:4379-4391. [PMID: 28932123 PMCID: PMC5598754 DOI: 10.2147/ott.s143518] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Accumulating evidence reveals that DEP-domain containing mTOR-interacting protein (DEPTOR) plays pivotal roles in the pathogenesis and progression of many tumors. However, the expression level of DEPTOR and its function in the tumorigenesis of osteosarcoma (OS) remain unknown. In this study, we conducted quantitative real-time polymerase chain reaction, Western blot, and immunohistochemistry to detect DEPTOR expression level in human OS tissues and cell lines. To assess DEPTOR function, DEPTOR siRNA was designed and transfected into OS cells, which were then used in a series of in vitro assays. Our results indicated that DEPTOR was highly expressed in some OS tissues and cell lines. DEPTOR knockdown by siRNA dramatically inhibited cell proliferation, migration, invasion, and the formation of vasculogenic mimicry in OS cells. In addition, DEPTOR knockdown induced cell cycle arrest in the G0/G1 phase and apoptosis in the OS cell lines, MG63 and MNNG/HOS. Furthermore, we found that DEPTOR knockdown notably activated mTOR and inhibited the PI3K/Akt pathway. Taken together, these results suggest that DEPTOR overexpression is necessary for the proliferation, migration, invasion, formation of vasculogenic mimicry, and survival of OS cells and may be a potential target for the treatment of OS.
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Affiliation(s)
- Binwu Hu
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiao Lv
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Feng Gao
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Songfeng Chen
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Shangyu Wang
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiangcheng Qing
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jianxiang Liu
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Baichuan Wang
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zengwu Shao
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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61
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DEPTOR maintains plasma cell differentiation and favorably affects prognosis in multiple myeloma. J Hematol Oncol 2017; 10:92. [PMID: 28420429 PMCID: PMC5395780 DOI: 10.1186/s13045-017-0461-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 03/31/2017] [Indexed: 11/24/2022] Open
Abstract
Background The B cell maturation process involves multiple steps, which are controlled by relevant pathways and transcription factors. The understanding of the final stages of plasma cell (PC) differentiation could provide new insights for therapeutic strategies in multiple myeloma (MM). Here, we explore the role of DEPTOR, an mTOR inhibitor, in the terminal differentiation of myeloma cells, and its potential impact on patient survival. Methods The expression level of DEPTOR in MM cell lines and B cell populations was measured by real-time RT-PCR, and/or Western blot analysis. DEPTOR protein level in MM patients was quantified by capillary electrophoresis immunoassay. RNA interference was used to downregulate DEPTOR in MM cell lines. Results DEPTOR knockdown in H929 and MM1S cell lines induced dedifferentiation of myeloma cells, as demonstrated by the upregulation of PAX5 and BCL6, the downregulation of IRF4, and a clear reduction in cell size and endoplasmic reticulum mass. This effect seemed to be independent of mTOR signaling, since mTOR substrates were not affected by DEPTOR knockdown. Additionally, the potential for DEPTOR to be deregulated in MM by particular miRNAs was investigated. The ectopic expression of miR-135b and miR-642a in myeloma cell lines substantially diminished DEPTOR protein levels, and caused dedifferentiation of myeloma cells. Interestingly, the level of expression of DEPTOR protein in myeloma patients was highly variable, the highest levels being associated with longer progression-free survival. Conclusions Our results demonstrate for the first time that DEPTOR expression is required to maintain myeloma cell differentiation and that high level of its expression are associated with better outcome. Primary samples used in this study correspond to patients entered into GEM2010 trial (registered at www.clinicaltrials.gov as #NCT01237249, 4 November 2010). Electronic supplementary material The online version of this article (doi:10.1186/s13045-017-0461-8) contains supplementary material, which is available to authorized users.
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