101
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Zhang Z, Zhang P, Qi GJ, Jiao FJ, Wang QZ, Yan JG, He F, Zhang Q, Lv ZX, Peng X, Cai HW, Chen X, Sun N, Tian B. CDK5-mediated phosphorylation of Sirt2 contributes to depressive-like behavior induced by social defeat stress. Biochim Biophys Acta Mol Basis Dis 2018; 1864:533-541. [DOI: 10.1016/j.bbadis.2017.11.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 10/19/2017] [Accepted: 11/16/2017] [Indexed: 02/02/2023]
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102
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Targeting PTEN in Colorectal Cancers. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1110:55-73. [DOI: 10.1007/978-3-030-02771-1_5] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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103
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Zhang Y, Zhao S, Wu D, Liu X, Shi M, Wang Y, Zhang F, Ding J, Xiao Y, Guo B. MicroRNA-22 Promotes Renal Tubulointerstitial Fibrosis by Targeting PTEN and Suppressing Autophagy in Diabetic Nephropathy. J Diabetes Res 2018; 2018:4728645. [PMID: 29850604 PMCID: PMC5903315 DOI: 10.1155/2018/4728645] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 01/03/2018] [Accepted: 01/14/2018] [Indexed: 12/11/2022] Open
Abstract
Renal tubulointerstitial fibrosis (TIF) is a major feature of diabetic nephropathy (DN). There is increasing evidence demonstrating that microRNAs act as key players in the regulation of autophagy and are involved in DN. However, the exact link among microRNAs, autophagy, and TIF in DN is largely unknown. In this study, our results showed that TIF was observed in DN rats together with obvious autophagy suppression. Moreover, microRNA-22 (miR-22) was upregulated and associated with reduced expression of its target gene phosphatase and tensin homolog (PTEN) in both the kidneys of DN rats and high glucose-cultured NRK-52E cells. Intriguingly, induction of autophagy by rapamycin antagonized high glucose-induced collagen IV (Col IV) and α-SMA expression. In addition, ectopic expression of miR-22 suppressed autophagic flux and induced the expression of Col IV and α-SMA, whereas the inhibition of endogenous miR-22 effectively relieved high glucose-induced autophagy suppression and the expression of Col IV and α-SMA in NRK-52E cells. Overexpression of PTEN protectively antagonized high glucose- and miR-22-induced autophagy suppression and the expression of Col IV. Therefore, our findings indicated that miR-22 may promote TIF by suppressing autophagy partially via targeting PTEN and represents a novel and promising therapeutic target for DN.
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Affiliation(s)
- Yingying Zhang
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou 550025, China
- Laboratory of Pathogenesis Research, Drug Prevention and Treatment of Major Diseases, Guizhou Medical University, Guiyang, Guizhou 550025, China
| | - Siqi Zhao
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou 550025, China
- Laboratory of Pathogenesis Research, Drug Prevention and Treatment of Major Diseases, Guizhou Medical University, Guiyang, Guizhou 550025, China
| | - Depei Wu
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou 550025, China
- Laboratory of Pathogenesis Research, Drug Prevention and Treatment of Major Diseases, Guizhou Medical University, Guiyang, Guizhou 550025, China
| | - Xingmei Liu
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou 550025, China
- Laboratory of Pathogenesis Research, Drug Prevention and Treatment of Major Diseases, Guizhou Medical University, Guiyang, Guizhou 550025, China
| | - Mingjun Shi
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou 550025, China
- Laboratory of Pathogenesis Research, Drug Prevention and Treatment of Major Diseases, Guizhou Medical University, Guiyang, Guizhou 550025, China
| | - Yuanyuan Wang
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou 550025, China
- Laboratory of Pathogenesis Research, Drug Prevention and Treatment of Major Diseases, Guizhou Medical University, Guiyang, Guizhou 550025, China
| | - Fan Zhang
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou 550025, China
- Laboratory of Pathogenesis Research, Drug Prevention and Treatment of Major Diseases, Guizhou Medical University, Guiyang, Guizhou 550025, China
| | - Jing Ding
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou 550025, China
- Laboratory of Pathogenesis Research, Drug Prevention and Treatment of Major Diseases, Guizhou Medical University, Guiyang, Guizhou 550025, China
| | - Ying Xiao
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou 550025, China
- Laboratory of Pathogenesis Research, Drug Prevention and Treatment of Major Diseases, Guizhou Medical University, Guiyang, Guizhou 550025, China
| | - Bing Guo
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou 550025, China
- Laboratory of Pathogenesis Research, Drug Prevention and Treatment of Major Diseases, Guizhou Medical University, Guiyang, Guizhou 550025, China
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104
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Statin and Bisphosphonate Induce Starvation in Fast-Growing Cancer Cell Lines. Int J Mol Sci 2017; 18:ijms18091982. [PMID: 28914765 PMCID: PMC5618631 DOI: 10.3390/ijms18091982] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 09/04/2017] [Accepted: 09/11/2017] [Indexed: 12/11/2022] Open
Abstract
Statins and bisphosphonates are increasingly recognized as anti-cancer drugs, especially because of their cholesterol-lowering properties. However, these drugs act differently on various types of cancers. Thus, the aim of this study was to compare the effects of statins and bisphosphonates on the metabolism (NADP+/NADPH-relation) of highly proliferative tumor cell lines from different origins (PC-3 prostate carcinoma, MDA-MB-231 breast cancer, U-2 OS osteosarcoma) versus cells with a slower proliferation rate like MG-63 osteosarcoma cells. Global gene expression analysis revealed that after 6 days of treatment with pharmacologic doses of the statin simvastatin and of the bisphosphonate ibandronate, simvastatin regulated more than twice as many genes as ibandronate, including many genes associated with cell cycle progression. Upregulation of starvation-markers and a reduction of metabolism and associated NADPH production, an increase in autophagy, and a concomitant downregulation of H3K27 methylation was most significant in the fast-growing cancer cell lines. This study provides possible explanations for clinical observations indicating a higher sensitivity of rapidly proliferating tumors to statins and bisphosphonates.
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105
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Bhore N, Wang BJ, Chen YW, Liao YF. Critical Roles of Dual-Specificity Phosphatases in Neuronal Proteostasis and Neurological Diseases. Int J Mol Sci 2017; 18:ijms18091963. [PMID: 28902166 PMCID: PMC5618612 DOI: 10.3390/ijms18091963] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 09/01/2017] [Accepted: 09/07/2017] [Indexed: 12/31/2022] Open
Abstract
Protein homeostasis or proteostasis is a fundamental cellular property that encompasses the dynamic balancing of processes in the proteostasis network (PN). Such processes include protein synthesis, folding, and degradation in both non-stressed and stressful conditions. The role of the PN in neurodegenerative disease is well-documented, where it is known to respond to changes in protein folding states or toxic gain-of-function protein aggregation. Dual-specificity phosphatases have recently emerged as important participants in maintaining balance within the PN, acting through modulation of cellular signaling pathways that are involved in neurodegeneration. In this review, we will summarize recent findings describing the roles of dual-specificity phosphatases in neurodegeneration and offer perspectives on future therapeutic directions.
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Affiliation(s)
- Noopur Bhore
- Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Yang-Ming University and Academia Sinica, Taipei 11529, Taiwan.
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan.
| | - Bo-Jeng Wang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan.
| | - Yun-Wen Chen
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan.
| | - Yung-Feng Liao
- Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Yang-Ming University and Academia Sinica, Taipei 11529, Taiwan.
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan.
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106
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Booth L, Roberts JL, Poklepovic A, Dent P. NEDD4 over-expression regulates the afatinib resistant phenotype of NSCLC cells. ACTA ACUST UNITED AC 2017; 1:19-30. [PMID: 30740589 DOI: 10.1016/j.onsig.2017.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
We focused on defining the role of the E3 ligase NEDD4 in NSCLC cell afatinib resistance. Afatinib resistant H1975 clones over-expressed NEDD4 and c-MET compared to control clones and expressed less ERBB1, ERBB3, ERBB4 and PTEN than control clones. Knock down of NEDD4 enhanced the expression of PTEN, ERBB1/3/4 and c-MET. This was also associated with a ∼3-fold enhancement in both mTOR expression and mTOR phosphorylation and a ∼4-fold elevation in phospho-ULK-1 S757 levels. In the absence of NEDD4 or the autophagy regulatory protein Beclin1, neither the drug combination of [pemetrexed + sildenafil] nor the HDAC inhibitor sodium valproate was as capable of: reducing the expression of ERBB1/3/4; reducing phosphorylation of ULK-1 S757; or at enhancing the phosphorylation of ULK-1 S317 and ATG13 S318. [Pemetrexed + sildenafil] exposure, via autophagic degradation, reduced the expression of multiple HDACs. Reduced expression of Class I HDACs lowered the expression of ERBB1/3/4 and PTEN. Treatment of afatinib resistant clones lacking NEDD4 with [pemetrexed + sildenafil] or sodium valproate resulted in a weaker induction of autophagosome and autolysosome formation and with reduced cell killing. Knock down of NEDD4 reduced [pemetrexed + sildenafil] lethality; knock down of PTEN enhanced drug-induced killing. Combined knock down of NEDD4 and PTEN reduced the elevated amount of killing caused by PTEN knock down alone back to basal levels. Collectively, our data argue that NEDD4 plays an essential role in maintaining the afatinib-resistant phenotype in our resistant H1975 clones.
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Affiliation(s)
| | | | - Andrew Poklepovic
- Departments of, Medicine, Virginia Commonwealth University, Richmond, VA 23298-0035
| | - Paul Dent
- Departments of Biochemistry and Molecular Biology
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107
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Sample A, He YY. Autophagy in UV Damage Response. Photochem Photobiol 2017; 93:943-955. [PMID: 27935061 PMCID: PMC5466513 DOI: 10.1111/php.12691] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 10/22/2016] [Indexed: 12/14/2022]
Abstract
UV radiation exposure from sunlight and artificial tanning beds is the major risk factor for the development of skin cancer and skin photoaging. UV-induced skin damage can trigger a cascade of DNA damage response signaling pathways, including cell cycle arrest, DNA repair and, if damage is irreparable, apoptosis. Compensatory proliferation replaces the apoptotic cells to maintain skin barrier integrity. Disruption of these processes can be exploited to promote carcinogenesis by allowing the survival and proliferation of damaged cells. UV radiation also induces autophagy, a catabolic process that clears unwanted or damaged proteins, lipids and organelles. The mechanisms by which autophagy is activated following UV exposure, and the functions of autophagy in UV response, are only now being clarified. Here, we summarize the current understanding of the mechanisms governing autophagy regulation by UV, the roles of autophagy in regulating cellular response to UV-induced photodamage and the implications of autophagy modulation in the treatment and prevention of photoaging and skin cancer.
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Affiliation(s)
- Ashley Sample
- Department of Medicine, Section of Dermatology, University of Chicago, Chicago, IL
- Committee on Cancer Biology, University of Chicago, Chicago, IL
| | - Yu-Ying He
- Department of Medicine, Section of Dermatology, University of Chicago, Chicago, IL
- Committee on Cancer Biology, University of Chicago, Chicago, IL
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108
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Wu Q, Allouch A, Martins I, Brenner C, Modjtahedi N, Deutsch E, Perfettini JL. Modulating Both Tumor Cell Death and Innate Immunity Is Essential for Improving Radiation Therapy Effectiveness. Front Immunol 2017; 8:613. [PMID: 28603525 PMCID: PMC5445662 DOI: 10.3389/fimmu.2017.00613] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Accepted: 05/09/2017] [Indexed: 12/17/2022] Open
Abstract
Radiation therapy is one of the cornerstones of cancer treatment. In tumor cells, exposure to ionizing radiation (IR) provokes DNA damages that trigger various forms of cell death such as apoptosis, necrosis, autophagic cell death, and mitotic catastrophe. IR can also induce cellular senescence that could serve as an additional antitumor barrier in a context-dependent manner. Moreover, accumulating evidence has demonstrated that IR interacts profoundly with tumor-infiltrating immune cells, which cooperatively drive treatment outcomes. Recent preclinical and clinical successes due to the combination of radiation therapy and immune checkpoint blockade have underscored the need for a better understanding of the interplay between radiation therapy and the immune system. In this review, we will present an overview of cell death modalities induced by IR, summarize the immunogenic properties of irradiated cancer cells, and discuss the biological consequences of IR on innate immune cell functions, with a particular attention on dendritic cells, macrophages, and NK cells. Finally, we will discuss their potential applications in cancer treatment.
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Affiliation(s)
- Qiuji Wu
- Cell Death and Aging Team, Gustave Roussy Cancer Campus, Villejuif, France.,Laboratory of Molecular Radiotherapy, INSERM U1030, Gustave Roussy Cancer Campus, Villejuif, France.,Gustave Roussy Cancer Campus, Villejuif, France.,Université Paris Saclay, Villejuif, France.,Department of Radiation and Medical Oncology, Zhongnan Hospital, Wuhan University, Wuhan, China.,Hubei Key Laboratory of Tumor Biological Behaviors, Zhongnan Hospital, Wuhan University, Wuhan, China
| | - Awatef Allouch
- Cell Death and Aging Team, Gustave Roussy Cancer Campus, Villejuif, France.,Laboratory of Molecular Radiotherapy, INSERM U1030, Gustave Roussy Cancer Campus, Villejuif, France.,Gustave Roussy Cancer Campus, Villejuif, France.,Université Paris Saclay, Villejuif, France
| | - Isabelle Martins
- Cell Death and Aging Team, Gustave Roussy Cancer Campus, Villejuif, France.,Laboratory of Molecular Radiotherapy, INSERM U1030, Gustave Roussy Cancer Campus, Villejuif, France.,Gustave Roussy Cancer Campus, Villejuif, France.,Université Paris Saclay, Villejuif, France
| | - Catherine Brenner
- Laboratory of Signaling and Cardiovascular Pathophysiology, INSERM UMR-S 1180, Université Paris-Sud, Faculté de Pharmacie, Châtenay-Malabry, France
| | - Nazanine Modjtahedi
- Laboratory of Molecular Radiotherapy, INSERM U1030, Gustave Roussy Cancer Campus, Villejuif, France.,Gustave Roussy Cancer Campus, Villejuif, France.,Université Paris Saclay, Villejuif, France
| | - Eric Deutsch
- Laboratory of Molecular Radiotherapy, INSERM U1030, Gustave Roussy Cancer Campus, Villejuif, France.,Gustave Roussy Cancer Campus, Villejuif, France.,Université Paris Saclay, Villejuif, France
| | - Jean-Luc Perfettini
- Cell Death and Aging Team, Gustave Roussy Cancer Campus, Villejuif, France.,Laboratory of Molecular Radiotherapy, INSERM U1030, Gustave Roussy Cancer Campus, Villejuif, France.,Gustave Roussy Cancer Campus, Villejuif, France.,Université Paris Saclay, Villejuif, France
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109
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He J, Long C, Huang Z, Zhou X, Kuang X, Liu L, Liu H, Tang Y, Fan Y, Ning J, Ma X, Zhang Q, Shen H. PTEN Reduced UVB-Mediated Apoptosis in Retinal Pigment Epithelium Cells. BIOMED RESEARCH INTERNATIONAL 2017; 2017:3681707. [PMID: 28321407 PMCID: PMC5340936 DOI: 10.1155/2017/3681707] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 01/22/2017] [Accepted: 01/26/2017] [Indexed: 02/06/2023]
Abstract
Age-related macular degeneration (AMD) is a leading cause of blindness and progressive loss of central vision in the elderly population. The important factor of AMD pathogenesis is the degeneration of retinal pigment epithelial (RPE) cells by oxidative stress. Inactivation of PTEN can disrupt intercellular adhesion in the RPE cells, but the mechanism of oxidative stress is less known. Here we presented evidence that UVB-mediated oxidative stress induced apoptosis in ARPE-19 cells. Downregulation of the expression of PTEN in UVB-irradiative RPE cells triggered DNA damage and increased the level of UVB-induced apoptosis by activating p53-dependent pathway. However, overexpression of PTEN increased cell survival by suppressing p-H2A in response to DNA damage and apoptosis. When using Pifithrin-α (one of p53 inhibitors), the level of p53-dependent apoptosis was significantly lower than untreated, which suggested that p53 was possibly involved in PTEN-dependent apoptosis. Thus, it elucidated the molecular mechanisms of UVB-induced damage in RPE cells and may offer an alternative therapeutic target in dry AMD.
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Affiliation(s)
- Jia He
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
| | - Chongde Long
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
| | - Zixin Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
| | - Xin Zhou
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
| | - Xielan Kuang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
- Biobank of Eye, State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
| | - Lanying Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
| | - Huijun Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
| | - Yan Tang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
| | - Yuting Fan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
| | - Jie Ning
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
| | - Xinqi Ma
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
| | - Qingjiong Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
| | - Huangxuan Shen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
- Biobank of Eye, State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 Xianlie Road, Guangzhou 510060, China
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110
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Contribution of classical end-joining to PTEN inactivation in p53-mediated glioblastoma formation and drug-resistant survival. Nat Commun 2017; 8:14013. [PMID: 28094268 PMCID: PMC5247582 DOI: 10.1038/ncomms14013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 11/21/2016] [Indexed: 02/07/2023] Open
Abstract
DNA repair gene defects are found in virtually all human glioblastomas, but the genetic evidence for a direct role remains lacking. Here we demonstrate that combined inactivation of the XRCC4 non-homologous end-joining (NHEJ) DNA repair gene and p53 efficiently induces brain tumours with hallmark characteristics of human proneural/classical glioblastoma. The murine tumours exhibit PTEN loss of function instigated by reduced PTEN mRNA, and increased phosphorylated inactivation and stability as a consequence of aberrantly elevated CK2 provoked by p53 ablation and irrevocably deregulated by NHEJ inactivation. This results in DNA damage-resistant cytoplasmic PTEN and CK2 expression, and the attenuation of DNA repair genes. CK2 inhibition restores PTEN nuclear distribution and DNA repair activities and impairs tumour but not normal cell survival. These observations demonstrate that NHEJ contributes to p53-mediated glioblastoma suppression, and reveal a crucial role for PTEN in the early DNA damage signalling cascade, the inhibition of which promotes tumorigenicity and drug-resistant survival. We know that defects in DNA repair genes are associated with cancer development. Here the authors eliminate XRCC4, a non-homologous end-joining protein, and p53 in the developing brain and find that this causes glioblastoma development as a consequence of reduced PTEN function.
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111
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Smida M, Fece de la Cruz F, Kerzendorfer C, Uras IZ, Mair B, Mazouzi A, Suchankova T, Konopka T, Katz AM, Paz K, Nagy-Bojarszky K, Muellner MK, Bago-Horvath Z, Haura EB, Loizou JI, Nijman SMB. MEK inhibitors block growth of lung tumours with mutations in ataxia-telangiectasia mutated. Nat Commun 2016; 7:13701. [PMID: 27922010 PMCID: PMC5150652 DOI: 10.1038/ncomms13701] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 10/26/2016] [Indexed: 01/04/2023] Open
Abstract
Lung cancer is the leading cause of cancer deaths, and effective treatments are urgently needed. Loss-of-function mutations in the DNA damage response kinase ATM are common in lung adenocarcinoma but directly targeting these with drugs remains challenging. Here we report that ATM loss-of-function is synthetic lethal with drugs inhibiting the central growth factor kinases MEK1/2, including the FDA-approved drug trametinib. Lung cancer cells resistant to MEK inhibition become highly sensitive upon loss of ATM both in vitro and in vivo. Mechanistically, ATM mediates crosstalk between the prosurvival MEK/ERK and AKT/mTOR pathways. ATM loss also enhances the sensitivity of KRAS- or BRAF-mutant lung cancer cells to MEK inhibition. Thus, ATM mutational status in lung cancer is a mechanistic biomarker for MEK inhibitor response, which may improve patient stratification and extend the applicability of these drugs beyond RAS and BRAF mutant tumours.
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Affiliation(s)
- Michal Smida
- Research Center for Molecular Medicine of the Austrian Academy of Sciences (CeMM), 1090 Vienna, Austria
- Central European Institute of Technology, Masaryk University, 62500 Brno, Czech Republic
| | - Ferran Fece de la Cruz
- Research Center for Molecular Medicine of the Austrian Academy of Sciences (CeMM), 1090 Vienna, Austria
- Nuffield Department of Clinical Medicine, Ludwig Institute for Cancer Research Ltd, University of Oxford, OX3 7FZ Oxford, UK
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, OX3 7FZ Oxford, UK
| | - Claudia Kerzendorfer
- Research Center for Molecular Medicine of the Austrian Academy of Sciences (CeMM), 1090 Vienna, Austria
| | - Iris Z. Uras
- Research Center for Molecular Medicine of the Austrian Academy of Sciences (CeMM), 1090 Vienna, Austria
| | - Barbara Mair
- Research Center for Molecular Medicine of the Austrian Academy of Sciences (CeMM), 1090 Vienna, Austria
- Nuffield Department of Clinical Medicine, Ludwig Institute for Cancer Research Ltd, University of Oxford, OX3 7FZ Oxford, UK
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, OX3 7FZ Oxford, UK
| | - Abdelghani Mazouzi
- Research Center for Molecular Medicine of the Austrian Academy of Sciences (CeMM), 1090 Vienna, Austria
| | - Tereza Suchankova
- Academy of Sciences of the Czech Republic, Institute of Biophysics, 61200 Brno, Czech Republic
| | - Tomasz Konopka
- Research Center for Molecular Medicine of the Austrian Academy of Sciences (CeMM), 1090 Vienna, Austria
- Nuffield Department of Clinical Medicine, Ludwig Institute for Cancer Research Ltd, University of Oxford, OX3 7FZ Oxford, UK
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, OX3 7FZ Oxford, UK
| | | | - Keren Paz
- Champions Oncology, Hackensack, New Jersey 07601, USA
| | - Katalin Nagy-Bojarszky
- Research Center for Molecular Medicine of the Austrian Academy of Sciences (CeMM), 1090 Vienna, Austria
| | - Markus K. Muellner
- Research Center for Molecular Medicine of the Austrian Academy of Sciences (CeMM), 1090 Vienna, Austria
| | - Zsuzsanna Bago-Horvath
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine, 1210 Vienna, Austria
- Clinical Institute of Pathology, Medical University of Vienna, 1090 Vienna, Austria
| | - Eric B. Haura
- Department of Thoracic Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida 33612, USA
| | - Joanna I. Loizou
- Research Center for Molecular Medicine of the Austrian Academy of Sciences (CeMM), 1090 Vienna, Austria
| | - Sebastian M. B. Nijman
- Research Center for Molecular Medicine of the Austrian Academy of Sciences (CeMM), 1090 Vienna, Austria
- Nuffield Department of Clinical Medicine, Ludwig Institute for Cancer Research Ltd, University of Oxford, OX3 7FZ Oxford, UK
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, OX3 7FZ Oxford, UK
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112
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PTEN Activation by DNA Damage Induces Protective Autophagy in Response to Cucurbitacin B in Hepatocellular Carcinoma Cells. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2016; 2016:4313204. [PMID: 28042385 PMCID: PMC5155108 DOI: 10.1155/2016/4313204] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 10/23/2016] [Accepted: 10/31/2016] [Indexed: 01/11/2023]
Abstract
Cucurbitacin B (Cuc B), a natural product, induced both protective autophagy and DNA damage mediated by ROS while the detailed mechanisms remain unclear. This study explored the mechanism of Cuc B-induced DNA damage and autophagy. Cuc B decreased cell viability in concentration- and time-dependent manners. Cuc B caused long comet tails and increased expression of γ-H2AX, phosphorylation of ATM/ATR, and Chk1/Chk2. Cuc B induced autophagy as evidenced by monodansylcadaverine (MDC) staining, increased expression of LC3II, phosphorylated ULK1, and decreased expression of phosphorylated AKT, mTOR. Cuc B induced apoptosis mediated by Bcl-2 family proteins and caspase activation. Furthermore, Cuc B induced ROS formation, which was inhibited by N-acetyl-L-cysteine (NAC). NAC pretreatment dramatically reversed Cuc B-induced DNA damage, autophagy, and apoptosis. Cuc B-induced apoptosis was reversed by NAC but enhanced by 3-methyladenine (3-MA), chloroquine (CQ), and silencing phosphatase and tensin homolog (PTEN). 3-MA and CQ showed no effect on Cuc B-induced DNA damage. In addition, Cuc B increased PTEN phosphorylation and silence PTEN restored Cuc B-induced autophagic protein expressions without affecting DNA damage. In summary, Cuc B induced DNA damage, apoptosis, and protective autophagy mediated by ROS. PTEN activation in response to DNA damage bridged DNA damage and prosurvival autophagy.
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113
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Mi S, Xiang G, Yuwen D, Gao J, Guo W, Wu X, Wu X, Sun Y, Su Y, Shen Y, Xu Q. Inhibition of autophagy by andrographolide resensitizes cisplatin-resistant non-small cell lung carcinoma cells via activation of the Akt/mTOR pathway. Toxicol Appl Pharmacol 2016; 310:78-86. [DOI: 10.1016/j.taap.2016.09.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 09/12/2016] [Accepted: 09/13/2016] [Indexed: 01/23/2023]
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114
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Zhu X, Pan Q, Huang N, Wu J, Zhen N, Sun F, Li Z, Yang Q. RAD51 regulates CHK1 stability via autophagy to promote cell growth in esophageal squamous carcinoma cells. Tumour Biol 2016; 37:10.1007/s13277-016-5455-6. [PMID: 27743378 DOI: 10.1007/s13277-016-5455-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 09/23/2016] [Indexed: 01/04/2023] Open
Abstract
The serine/threonine protein kinase CHK1 has been reported to bind to the recombinase RAD51 and facilitates its assembly in DNA damage sites via phosphorylation. However, the role of RAD51 in regulating the expression of CHK1 has never been explored. Here, we show that RAD51 is highly upregulated in esophageal squamous tumor tissues and its DMC1 domain significantly promotes cell growth of esophageal cancer (EC) cells through CHK1. To gain the mechanistic insights, firstly, in the presence of 3-methyladenine (3MA), an autophagy inhibitor, we found that the reduction of CHK1 and the inhibition of cell growth in RAD51-deficient EC109 cells were strikingly restored. Subsequently, the autophagy-related experiments revealed that RAD51 negatively participated in autophagy. Moreover, results from in vitro clonogenic survival assays showed that RAD51 depletion greatly enabled EC cells to resist the autophagy inhibitors 3MA and hydroxychloroquine (HCQ) treatments. Above all, our studies firstly highlight a direct role of RAD51 in autophagy process and characterize its functional domain in cell growth regulation. Moreover, our data firstly shed insights into the possible application of autophagy inhibitors in treating RAD51 overexpressed EC patients.
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Affiliation(s)
- Xinyi Zhu
- Department of Clinical Laboratory Medicine, Tenth People's Hospital of Tongji University, Shanghai, 200072, China
| | - Qiuhui Pan
- Central Laboratory, Tenth People's Hospital of Tongji University, Shanghai, 200072, China
| | - Nan Huang
- Department of Clinical Laboratory Medicine, Tenth People's Hospital of Tongji University, Shanghai, 200072, China
| | - Jianchun Wu
- Department of oncology, Shanghai Municipal Hospital of Traditional Chinese Medicine, Shanghai, 200071, China
| | - Ni Zhen
- Department of Clinical Laboratory Medicine, Tenth People's Hospital of Tongji University, Shanghai, 200072, China
| | - Fenyong Sun
- Department of Clinical Laboratory Medicine, Tenth People's Hospital of Tongji University, Shanghai, 200072, China
| | - Zhi Li
- Department of Clinical Laboratory Medicine, Yangpu Hospital of Tongji University, Shanghai, 200090, China.
| | - Qingyuan Yang
- Department of Clinical Laboratory Medicine, Tenth People's Hospital of Tongji University, Shanghai, 200072, China.
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115
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Luo M, Zhao X, Song Y, Cheng H, Zhou R. Nuclear autophagy: An evolutionarily conserved mechanism of nuclear degradation in the cytoplasm. Autophagy 2016; 12:1973-1983. [PMID: 27541589 DOI: 10.1080/15548627.2016.1217381] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Macroautophagy/autophagy is a catabolic process that is essential for cellular homeostasis. Studies on autophagic degradation of cytoplasmic components have generated interest in nuclear autophagy. Although its mechanisms and roles have remained elusive, tremendous progress has been made toward understanding nuclear autophagy. Nuclear autophagy is evolutionarily conserved in eukaryotes that may target various nuclear components through a series of processes, including nuclear sensing, nuclear export, autophagic substrate encapsulation and autophagic degradation in the cytoplasm. However, the molecular processes and regulatory mechanisms involved in nuclear autophagy remain largely unknown. Numerous studies have highlighted the importance of nuclear autophagy in physiological and pathological processes such as cancer. This review focuses on current advances in nuclear autophagy and provides a summary of its research history and landmark discoveries to offer new perspectives.
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Affiliation(s)
- Majing Luo
- a Hubei Key Laboratory of Cell Homeostasis, Laboratory of Molecular and Developmental Genetics, College of Life Sciences , Wuhan University , Wuhan , China
| | - Xueya Zhao
- a Hubei Key Laboratory of Cell Homeostasis, Laboratory of Molecular and Developmental Genetics, College of Life Sciences , Wuhan University , Wuhan , China
| | - Ying Song
- a Hubei Key Laboratory of Cell Homeostasis, Laboratory of Molecular and Developmental Genetics, College of Life Sciences , Wuhan University , Wuhan , China
| | - Hanhua Cheng
- a Hubei Key Laboratory of Cell Homeostasis, Laboratory of Molecular and Developmental Genetics, College of Life Sciences , Wuhan University , Wuhan , China
| | - Rongjia Zhou
- a Hubei Key Laboratory of Cell Homeostasis, Laboratory of Molecular and Developmental Genetics, College of Life Sciences , Wuhan University , Wuhan , China
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116
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Wang W, Liu M, Guan Y, Wu Q. Hypoxia-Responsive Mir-301a and Mir-301b Promote Radioresistance of Prostate Cancer Cells via Downregulating NDRG2. Med Sci Monit 2016; 22:2126-32. [PMID: 27327120 PMCID: PMC4920099 DOI: 10.12659/msm.896832] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 12/10/2015] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND MiR-301a and miR-301b are 2 oncomiRs involved in multiple types of cancer. In this study, we explored the expression change of miR-301a and miR-301b in prostate cancer cells in hypoxia and studied their regulation of autophagy and radiosensitivity of prostate cancer cells. MATERIAL AND METHODS QRT-PCR was performed to quantify the expression change of miR-301a and miR-301b in hypoxia. Their effects on autophagy were measured by Western blot analysis, and their effects on radiosensitivity were measured by clonogenic assay and flow cytometry. In addition, the regulation of miR-301a and miR-301b on NDRG2, a tumor-suppressor gene in prostate cancer, was also studied. The effect of miR-301a/b-NDRG2 axis on autophagy and radiosensitivity of prostate cancer cells was further investigated. RESULTS MiR-301a and miR-301b are 2 hypoxia responsive miRNAs that are significantly upregulated in hypoxia in prostate cancer cells. Higher level of miR-301a and miR-301b expression results in elevated autophagy and increased radioresistance in LNCaP cells. MiR-301a and miR-301b simultaneously target NDRG2 and decrease its expression. Knockdown of NDRG2 leads to increased autophagy and radioresistance. CONCLUSIONS MiR-301a and miR-301b are 2 hypoxia-responsive miRNAs that decrease autophagy of prostate cancer cells in hypoxia by targeting NDRG2. Through downregulating NDRG2, miR-301a and miR-301b can promote radioresistance of prostate cancer cells.
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Affiliation(s)
- Wei Wang
- Department of Radiation Oncology, Henan Provincial People’s Hospital, Zhengzhou, Henan, P.R. China
| | - Mingbo Liu
- Department of Radiation Oncology, Henan Provincial People’s Hospital, Zhengzhou, Henan, P.R. China
| | - Yawei Guan
- Department of Urology, General Hospital of Beijing Military Region, PLA, Beijing, P.R. China
| | - Qingwu Wu
- Department of Medical Imaging, The First Affiliated Hospital of Xinxiang Medical University, Weihui, Henan, P.R. China
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117
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Stumpf M, Blokzijl-Franke S, den Hertog J. Fine-Tuning of Pten Localization and Phosphatase Activity Is Essential for Zebrafish Angiogenesis. PLoS One 2016; 11:e0154771. [PMID: 27138341 PMCID: PMC4854392 DOI: 10.1371/journal.pone.0154771] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 04/19/2016] [Indexed: 02/06/2023] Open
Abstract
The lipid- and protein phosphatase PTEN is an essential tumor suppressor that is highly conserved among all higher eukaryotes. As an antagonist of the PI3K/Akt cell survival and proliferation pathway, it exerts its most prominent function at the cell membrane, but (PIP3-independent) functions of nuclear PTEN have been discovered as well. PTEN subcellular localization is tightly controlled by its protein conformation. In the closed conformation, PTEN localizes predominantly to the cytoplasm. Opening up of the conformation of PTEN exposes N-terminal and C-terminal regions of the protein that are required for both interaction with the cell membrane and translocation to the nucleus. Lack of Pten leads to hyperbranching of the intersegmental vessels during zebrafish embryogenesis, which is rescued by expression of exogenous Pten. Here, we observed that expression of mutant PTEN with an open conformation rescued the hyperbranching phenotype in pten double homozygous embryos and suppressed the increased p-Akt levels that are characteristic for embryos lacking Pten. In addition, in pten mutant and wild type embryos alike, open conformation PTEN induced stalled intersegmental vessels, which fail to connect with the dorsal longitudinal anastomotic vessel. Functional hyperactivity of open conformation PTEN in comparison to wild type PTEN seems to result predominantly from its enhanced recruitment to the cell membrane. Enhanced recruitment of phosphatase inactive mutants to the membrane did not induce the stalled vessel phenotype nor did it rescue the hyperbranching phenotype in pten double homozygous embryos, indicating that PTEN phosphatase activity is indispensable for its regulatory function during angiogenesis. Taken together, our data suggest that PTEN phosphatase activity needs to be carefully fine-tuned for normal embryogenesis and that the control of its subcellular localization is a key mechanism in this process.
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Affiliation(s)
- Miriam Stumpf
- Hubrecht Institute–Koninklijke Nederlandse Akademie van Wetenschappen (KNAW) and University Medical Center Utrecht, Utrecht, The Netherlands
| | - Sasja Blokzijl-Franke
- Hubrecht Institute–Koninklijke Nederlandse Akademie van Wetenschappen (KNAW) and University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jeroen den Hertog
- Hubrecht Institute–Koninklijke Nederlandse Akademie van Wetenschappen (KNAW) and University Medical Center Utrecht, Utrecht, The Netherlands
- Institute of Biology Leiden, Leiden University, Leiden, The Netherlands
- * E-mail:
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118
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Abstract
Autophagy constitutes a prominent mechanism through which eukaryotic cells preserve homeostasis in baseline conditions and in response to perturbations of the intracellular or extracellular microenvironment. Autophagic responses can be relatively non-selective or target a specific subcellular compartment. At least in part, this depends on the balance between the availability of autophagic substrates ("offer") and the cellular need of autophagic products or functions for adaptation ("demand"). Irrespective of cargo specificity, adaptive autophagy relies on a panel of sensors that detect potentially dangerous cues and convert them into signals that are ultimately relayed to the autophagic machinery. Here, we summarize the molecular systems through which specific subcellular compartments-including the nucleus, mitochondria, plasma membrane, reticular apparatus, and cytosol-convert homeostatic perturbations into an increased offer of autophagic substrates or an accrued cellular demand for autophagic products or functions.
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119
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Costa L, Amaral C, Teixeira N, Correia-da-Silva G, Fonseca BM. Cannabinoid-induced autophagy: Protective or death role? Prostaglandins Other Lipid Mediat 2015; 122:54-63. [PMID: 26732541 DOI: 10.1016/j.prostaglandins.2015.12.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 12/07/2015] [Accepted: 12/21/2015] [Indexed: 12/11/2022]
Abstract
Autophagy, the "self-digestion" mechanism of the cells, is an evolutionary conserved catabolic process that targets portions of cytoplasm, damaged organelles and proteins for lysosomal degradation, which plays a crucial role in development and disease. Cannabinoids are active compounds of Cannabis sativa and the most prevalent psychoactive substance is Δ(9)-tetrahydrocannabinol (THC). Cannabinoid compounds can be divided in three types: the plant-derived natural products (phytocannabinoids), the cannabinoids produced endogenously (endocannabinoids) and the synthesized compounds (synthetic cannabinoids). Various studies reported a cannabinoid-induced autophagy mechanism in cancer and non-cancer cells. In this review we focus on the recent advances in the cannabinoid-induced autophagy and highlight the molecular mechanisms involved in these processes.
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Affiliation(s)
- Lia Costa
- Departamento de Biologia, Universidade de Aveiro, Portugal; UCIBIO, REQUIMTE, Laboratório de Bioquímica, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Portugal
| | - Cristina Amaral
- UCIBIO, REQUIMTE, Laboratório de Bioquímica, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Portugal
| | - Natércia Teixeira
- UCIBIO, REQUIMTE, Laboratório de Bioquímica, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Portugal
| | - Georgina Correia-da-Silva
- UCIBIO, REQUIMTE, Laboratório de Bioquímica, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Portugal
| | - Bruno M Fonseca
- UCIBIO, REQUIMTE, Laboratório de Bioquímica, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Portugal.
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120
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Abstract
Apoptosis and autophagy are both highly regulated biological processes that have important roles in development, differentiation, homeostasis, and disease. These processes may take place independently, with autophagy being cytoprotective for preventing cells from apoptosis and apoptosis blocking autophagy. But in most circumstances, both may be induced sequentially with autophagy preceding apoptosis. The simultaneous activation of both processes has been observed not only in experimental settings but also in pathophysiological conditions. In fact, these two pathways are tightly connected with each other by substantial interplays between them, enabling the coordinated regulation of cell fates by these two pathways. They share some common upstream signaling components, and some components of one pathway may play important roles in the other, and vice versa. Such proteins represent the critical interconnections of the two pathways, which seem to determine the cell for survival or death. Here several critical molecular interconnections between apoptosis and autophagy pathways are reviewed, with their action mechanisms being highlighted.
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Affiliation(s)
- Gao-Xiang Zhao
- Department of Immunobiology, College of Life Science and Technology, Jinan University , Guangzhou 510632 , China
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121
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Yu X, Long YC, Shen HM. Differential regulatory functions of three classes of phosphatidylinositol and phosphoinositide 3-kinases in autophagy. Autophagy 2015; 11:1711-28. [PMID: 26018563 PMCID: PMC4824607 DOI: 10.1080/15548627.2015.1043076] [Citation(s) in RCA: 135] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 04/11/2015] [Accepted: 04/14/2015] [Indexed: 02/06/2023] Open
Abstract
Autophagy is an evolutionarily conserved and exquisitely regulated self-eating cellular process with important biological functions. Phosphatidylinositol 3-kinases (PtdIns3Ks) and phosphoinositide 3-kinases (PI3Ks) are involved in the autophagic process. Here we aim to recapitulate how 3 classes of these lipid kinases differentially regulate autophagy. Generally, activation of the class I PI3K suppresses autophagy, via the well-established PI3K-AKT-MTOR (mechanistic target of rapamycin) complex 1 (MTORC1) pathway. In contrast, the class III PtdIns3K catalytic subunit PIK3C3/Vps34 forms a protein complex with BECN1 and PIK3R4 and produces phosphatidylinositol 3-phosphate (PtdIns3P), which is required for the initiation and progression of autophagy. The class II enzyme emerged only recently as an alternative source of PtdIns3P and autophagic initiator. However, the orthodox paradigm is challenged by findings that the PIK3CB catalytic subunit of class I PI3K acts as a positive regulator of autophagy, and PIK3C3 was thought to be an amino acid sensor for MTOR, which curbs autophagy. At present, a number of PtdIns3K and PI3K inhibitors, including specific PIK3C3 inhibitors, have been developed for suppression of autophagy and for clinical applications in autophagy-related human diseases.
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Affiliation(s)
- Xinlei Yu
- a Department of Biochemistry; Yong Loo Lin School of Medicine, National University of Singapore ; Singapore
| | - Yun Chau Long
- a Department of Biochemistry; Yong Loo Lin School of Medicine, National University of Singapore ; Singapore
| | - Han-Ming Shen
- b Department of Physiology; Yong Loo Lin School of Medicine, National University of Singapore ; Singapore
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