101
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Yao D, Jiang Y, Gao S, Shang L, Zhao Y, Huang J, Wang J, Yang S, Chen L. Deconvoluting the complexity of microRNAs in autophagy to improve potential cancer therapy. Cell Prolif 2016; 49:541-53. [PMID: 27436709 DOI: 10.1111/cpr.12277] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Accepted: 06/20/2016] [Indexed: 12/17/2022] Open
Abstract
MicroRNAs (miRNAs) (small, non-coding RNAs ∼22 nucleotides [nt] in length), have been estimated to regulate in the region of 30% of human gene expression at the post-transcriptional and translational levels. They are also involved in a series of important cellular processes, such as autophagy. Autophagy is well-known to be an evolutionarily conserved lysosomal degradation process in which a cell degrades long-lived proteins and damaged organelles. Recent evidence has shown that miRNAs can function as either oncogenes or tumour-suppressive genes in human cancers. Also, they are well-characterized to be crucial in tumourigenesis, as either oncogenes or tumour suppressors, by regulating autophagy. However, discovering the intricate mechanism of miRNA-modulated autophagy remains in its infancy. Thus, in this review, we focus on summarizing the dual function of oncogenic or tumour-suppressive miRNAs in regulation of autophagy and their roles in carcinogenesis, thereby revealing the regulatory mechanism of miRNA-modulated autophagy in cancer, to shed light on more novel RNA therapeutic strategies in the future.
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Affiliation(s)
- Dahong Yao
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Yingnan Jiang
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Suyu Gao
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Lei Shang
- School of Pharmacy, China Medical University, Shenyang, 110122, China
| | - Yuqian Zhao
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Jian Huang
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Jinhui Wang
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, 110016, China.
| | - Shilin Yang
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, 110016, China.
| | - Lixia Chen
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, 110016, China.
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102
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Hu Z, Zhong Z, Huang S, Wen H, Chen X, Chu H, Li Q, Sun C. Decreased expression of Beclin‑1 is significantly associated with a poor prognosis in oral tongue squamous cell carcinoma. Mol Med Rep 2016; 14:1567-73. [PMID: 27356955 PMCID: PMC4940089 DOI: 10.3892/mmr.2016.5437] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Accepted: 04/29/2016] [Indexed: 01/07/2023] Open
Abstract
The autophagy-related gene Beclin-1 is critical in the regulation of tumourigenesis and progression, but its role in oral tongue squamous cell carcinoma (OTSCC) has not yet been reported. This study aimed to investigate Beclin-1 expression and its significance in OTSCC. Beclin-1 expression was assessed by reverse transcription-quantitative polymerase chain reaction or western blot analysis in 14 OTSCC tissues and matched adjacent noncancerous tissues as well as in 5 OTSCC cell lines and a normal tongue epithelial cell line. Beclin-1 protein expression was examined by immunohistochemistry in 133 OTSCC specimens, and the correlation between Beclin-1 expression and clinicopathological features was investigated. Furthermore, MTT and colony formation assays were performed to investigate the effect of Beclin-1 on the proliferation and clonogenicity of OTSCC cells. It was demonstrated that Beclin-1 expression was significantly decreased in the majority of the 14 OTSCC tissues and the 5 OTSCC cell lines relative to the matched non-cancerous tissues and the normal tongue epithelial cell line, respectively. Immunohistochemistry analysis revealed that decreased Beclin-1 expression was significantly correlated with poor differentiation, lymph node metastasis, advanced clinical tumour-node-metastasis stage, and a poor prognosis in patients with OTSCC. The in vitro assays indicated that the overexpression of Beclin-1 significantly inhibits the proliferation and clonogenicity of OTSCC cells. These results demonstrate that Beclin-1 acts as a tumour suppressor in the development or progression of OTSCC and that Beclin-1 may represent a novel prognostic marker for patients with OTSCC.
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Affiliation(s)
- Zedong Hu
- Department of Head and Neck Surgery, The Third Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650118, P.R. China
| | - Zhaoming Zhong
- Department of Head and Neck Surgery, The Third Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650118, P.R. China
| | - Shaohui Huang
- Department of Oral and Maxillofacial Surgery, School of Stomatology, China Medical University, Shenyang, Liaoning 110002, P.R. China
| | - Haojie Wen
- Department of Head and Neck Surgery, The Third Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650118, P.R. China
| | - Xue Chen
- Department of Head and Neck Surgery, The Third Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650118, P.R. China
| | - Hongying Chu
- Department of Head and Neck Surgery, The Third Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650118, P.R. China
| | - Qiuli Li
- Department of Head and Neck Surgery, Sun Yat‑sen University Cancer Center, Guangzhou, Guangdong 510060, P.R. China
| | - Chuanzheng Sun
- Department of Head and Neck Surgery, The Third Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650118, P.R. China
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103
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Rothschild SI, Gautschi O, Batliner J, Gugger M, Fey MF, Tschan MP. MicroRNA-106a targets autophagy and enhances sensitivity of lung cancer cells to Src inhibitors. Lung Cancer 2016; 107:73-83. [PMID: 27372519 DOI: 10.1016/j.lungcan.2016.06.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 05/30/2016] [Accepted: 06/10/2016] [Indexed: 02/07/2023]
Abstract
OBJECTIVES Src tyrosine kinase inhibitors (TKIs) significantly inhibit cell migration and invasion in lung cancer cell lines with minor cytotoxic effects. In clinical trials, however, they show modest activity in combination with chemotherapeutic agents. Possible resistance mechanisms include the induction of cytoprotective autophagy upon Src inhibition. Autophagy is a cellular recycling process that allows cell survival in response to a variety of stress stimuli including responses to various treatments. MATERIAL AND METHODS We screened autophagic activity in A549, H460, and H1299 NSCLC cell lines treated with two different Src-TKIs (saracatinib, dasatinib) or shRNA targeting SRC. The autophagy response was determined by LC3B-I to -II conversion, increased ULK1 epxression and increased GFP-LC3B dot formation. Autophagy was inhibited by pharmacological (bafilomycin A, chloroquine) or genetic (ULK1 shRNA) means. Expression of miR-106a and miR-20b was analyzed by qPCR, and we used different lentivral vectors for ectopic expression of either miR-106a mimetics, anti-sense miR-106a or different miR-106a-363 cluster constructs. RESULTS In the current study we found that Src-TKIs induce autophagy in lung adenocarcinoma cell lines and that a combination of autophagy and Src tyrosine kinase inhibition results in cell death. Moreover, Src-TKI induced autophagy depends on the induction of the key autophagy kinase ULK1. This ULK1 upregulation is caused by downregulation of the ULK1-targeting microRNA-106a. An inverse correlation of miR-106a and ULK1 expression was seen in lung adenocarcinoma. Accordingly, ectopic expression of miR-106a in combination with Src-TKI treatment resulted in significant cell death as compared to control transduced cells. CONCLUSIONS Autophagy protects lung adenocarcinoma cells from Src-TKIs via a newly identified miR-106a-ULK1 signaling pathway. The combined inhibition of Src and ULK1/autophagy might represent a promising treatment option for future clinical trials. Lastly, our data might challenge the term "oncogenic" miR-106a as it can promote sensitivity to Src-TKIs thereby underlining the context-dependent function of miRNAs.
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Affiliation(s)
- Sacha I Rothschild
- Department of Medical Oncology, Inselspital, Bern University Hospital, Switzerland; Department of Clinical Research, University of Bern, Bern, Switzerland; Department Internal Medicine, Medical Oncology, University Hospital Basel, Basel, Switzerland
| | - Oliver Gautschi
- Department of Medical Oncology, Inselspital, Bern University Hospital, Switzerland; Medical Oncology, Cantonal Hospital, Luzern, Switzerland
| | - Jasmin Batliner
- Department of Clinical Research, University of Bern, Bern, Switzerland
| | - Mathias Gugger
- Division of Experimental Pathology, Institute of Pathology, University of Bern, Bern, Switzerland
| | - Martin F Fey
- Department of Medical Oncology, Inselspital, Bern University Hospital, Switzerland; Department of Clinical Research, University of Bern, Bern, Switzerland
| | - Mario P Tschan
- Division of Experimental Pathology, Institute of Pathology, University of Bern, Bern, Switzerland.
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104
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Hjelmeland A, Zhang J. Metabolic, autophagic, and mitophagic activities in cancer initiation and progression. Biomed J 2016; 39:98-106. [PMID: 27372165 PMCID: PMC5514543 DOI: 10.1016/j.bj.2015.10.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 10/19/2015] [Indexed: 12/11/2022] Open
Abstract
Cancer is a complex disease marked by uncontrolled cell growth and invasion. These processes are driven by the accumulation of genetic and epigenetic alterations that promote cancer initiation and progression. Contributing to genome changes are the regulation of oxidative stress and reactive species-induced damage to molecules and organelles. Redox regulation, metabolic plasticity, autophagy, and mitophagy play important and interactive roles in cancer hallmarks including sustained proliferation, activated invasion, and replicative immortality. However, the impact of these processes can differ depending on the signaling pathways altered in cancer, tumor type, tumor stage, and/or the differentiation state. Here, we highlight some of the representative studies on the impact of oxidative and nitrosative activities, mitochondrial bioenergetics, metabolism, and autophagy and mitophagy in the context of tumorigenesis. We discuss the implications of these processes for cellular activities in cancer for anti-cancer-based therapeutics.
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Affiliation(s)
- Anita Hjelmeland
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, USA; Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jianhua Zhang
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL, USA; Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA; Department of Veterans Affairs, Birmingham VA Medical Center, Birmingham, AL, USA.
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105
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Gomes LR, Vessoni AT, Menck CF. Microenvironment and autophagy cross-talk: Implications in cancer therapy. Pharmacol Res 2016; 107:300-307. [DOI: 10.1016/j.phrs.2016.03.031] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 03/25/2016] [Accepted: 03/27/2016] [Indexed: 02/07/2023]
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106
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Choi SR, Chung BY, Kim SW, Kim CD, Yun WJ, Lee MW, Choi JH, Chang SE. Activation of autophagic pathways is related to growth inhibition and senescence in cutaneous squamous cell carcinoma. Exp Dermatol 2016; 23:718-24. [PMID: 25046976 DOI: 10.1111/exd.12515] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/17/2014] [Indexed: 12/21/2022]
Abstract
Cutaneous squamous cell carcinoma (SCC) is a very common resectable cancer; however, cutaneous SCC is highly resistant to chemotherapy if metastasis develops. Activating transcription factor 3 (ATF3) has been suggested as a marker of advanced or metastatic cutaneous SCC. Autophagy is one of the most important mechanisms in cancer biology and commonly induced by in vitro serum starvation. To investigate the role of autophagy activation in cutaneous SCC, we activated autophagic pathways by serum starvation in SCC13 and ATF3-overexpressing SCC13 (ATF3-SCC13) cell lines. ATF3-SCC13 cells demonstrated high proliferative capacity and low p53 and autophagy levels in comparison with control SCC13 cells under basal conditions. Intriguingly, autophagic stimulation via serum starvation resulted in growth inhibition and senescence in both cells, while ATF3-SCC13 cells further demonstrated growth inhibition and senescence. Apoptosis was not significantly induced by autophagy activation. Taken together, autophagy activation may be a promising antitumor approach for advanced cutaneous SCC.
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Affiliation(s)
- So Ra Choi
- Department of Dermatology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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107
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Unraveling the roles of Atg4 proteases from autophagy modulation to targeted cancer therapy. Cancer Lett 2016; 373:19-26. [DOI: 10.1016/j.canlet.2016.01.022] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 01/12/2016] [Accepted: 01/12/2016] [Indexed: 11/22/2022]
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108
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Therapy-induced microenvironmental changes in cancer. J Mol Med (Berl) 2016; 94:497-508. [DOI: 10.1007/s00109-016-1401-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Revised: 02/22/2016] [Accepted: 02/25/2016] [Indexed: 02/06/2023]
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109
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Chagin AS. Effectors of mTOR-autophagy pathway: targeting cancer, affecting the skeleton. Curr Opin Pharmacol 2016; 28:1-7. [PMID: 26921601 DOI: 10.1016/j.coph.2016.02.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 01/23/2016] [Accepted: 02/09/2016] [Indexed: 12/17/2022]
Abstract
Although some modulators of autophagy are emerging as drugs or supplements for anti-cancer therapy, the effects of these compounds on normal tissues must be examined carefully. Here, I review the role of autophagy in skeletal tissues in this context. First, I briefly review preclinical studies indicating the role of autophagy in cancer, as well as related on-going clinical trials. Thereafter, the role of autophagy in the physiology of skeletal tissues is discussed, with a focus on recent genetic preclinical studies. Specifically, I discuss the mTOR-autophagy pathway in relationship to epiphyseal chondrocytes, articular chondrocytes, osteoblasts, osteocytes and osteoclasts and potential side effects of targeting either mTOR pathway or autophagy in general in connection with anti-cancer therapy. Current preclinical findings indicate that inhibiting autophagy will not seriously reduce bone mass and enhance osteoporosis. However, inhibition of autophagy might damage articular cartilage and cause osteoarthritis, whereas treatment with rapalogs might result in relatively beneficial effects on articular cartilage. Modulation of the mTOR pathway or autophagy during childhood may have an undesirable influence on adult height, as well as acquisition of bone mass.
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Affiliation(s)
- Andrei S Chagin
- Department of Physiology and Pharmacology, Karolinska Institutet, Sweden.
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110
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Dash S, Chava S, Chandra PK, Aydin Y, Balart LA, Wu T. Autophagy in hepatocellular carcinomas: from pathophysiology to therapeutic response. Hepat Med 2016; 8:9-20. [PMID: 26955295 PMCID: PMC4772942 DOI: 10.2147/hmer.s63700] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Autophagy is an intracellular lysosomal degradation process performed by the cells to maintain energy balance. The autophagy response plays an important role in the progression of liver disease due to hepatitis virus infection, alcoholic liver disease, nonalcoholic fatty liver disease, liver cirrhosis, and hepatocellular carcinoma (HCC). An increased autophagy response also contributes to the pathogenesis of liver disease through modulation of innate and adaptive immune responses; a defective cellular autophagy response leads to the development of HCC. Recent progress in the field indicates that autophagy modulation provides a novel targeted therapy for human liver cancer. The purpose of this review is to update our understanding of how the cellular autophagy response impacts the pathophysiology of liver disease and HCC treatment.
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Affiliation(s)
- Srikanta Dash
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA, USA; Department of Gastroenterology and Hepatology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Srinivas Chava
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA, USA
| | - Partha K Chandra
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA, USA
| | - Yucel Aydin
- Department of Gastroenterology and Hepatology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Luis A Balart
- Department of Gastroenterology and Hepatology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Tong Wu
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA, USA
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111
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Lee JS, Oh E, Yoo JY, Choi KS, Yoon MJ, Yun CO. Adenovirus expressing dual c-Met-specific shRNA exhibits potent antitumor effect through autophagic cell death accompanied by senescence-like phenotypes in glioblastoma cells. Oncotarget 2016; 6:4051-65. [PMID: 25726528 PMCID: PMC4414172 DOI: 10.18632/oncotarget.3018] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 12/30/2014] [Indexed: 12/12/2022] Open
Abstract
c-Met, a cognate receptor tyrosine kinase of hepatocyte growth factor, is overexpressed and/or mutated in number of tumors. Therefore, abrogation of c-Met signaling may serve as potential therapeutic targets. In this study, we generated Ads expressing single shRNA specific to c-Met (shMet) (dl/shMet4 and dl/shMet5) or dual shRNAs specific to c-Met (dl/shMet4+5); and examined the therapeutic potential of these newly engineered Ads in targeting c-Met, and delineated their mechanism of action in vitro and in vivo. Ads expressing shMet induced knock-down in c-Met, and phenotypically resulted in autophagy-like features including appearance of membranousvacuoles, formation of acidic vesicular organelles, and cleavage and recruitment of microtubule-associated protein1 light chain 3 to autophagosomes. Ads expressing shMet also suppressed Akt phosphorylation and increased number of senescence-related gene products including SM22, TGase II, and PAI-1. These changes resulted in inhibition of cell proliferation and G2/M arrest of U343 cells. In vivo, intratumoral injection with dl/shMet4+5 resulted in a significant reduction of tumor growth with corresponding increasing overall survival. Histopathological analysis of these treated tumors revealed that Atg5 was highly up-regulated, indicating the therapeutic induction of autophagy. In sum, these results reveal that autophagic cell death induced by shMet-expressing Ads provide a novel strategy for targeting c-Met-expressing tumors through non-apoptotic mechanism of cell death.
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Affiliation(s)
- Jung-Sun Lee
- Institute for Cancer Research, Yonsei University College of Medicine, Seoul, Korea
| | - Eonju Oh
- Department of Bioengineering, College of Engineering, Hanyang University, Seoul, Korea
| | - Ji Young Yoo
- Institute for Cancer Research, Yonsei University College of Medicine, Seoul, Korea
| | - Kyeong Sook Choi
- Department of Molecular Science & Technology, Institute for Medical Sciences, Ajou University School of Medicine, Suwon, Korea
| | - Mi Jin Yoon
- Department of Molecular Science & Technology, Institute for Medical Sciences, Ajou University School of Medicine, Suwon, Korea
| | - Chae-Ok Yun
- Department of Bioengineering, College of Engineering, Hanyang University, Seoul, Korea
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112
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Mukhopadhyay S, Sinha N, Das DN, Panda PK, Naik PP, Bhutia SK. Clinical relevance of autophagic therapy in cancer: Investigating the current trends, challenges, and future prospects. Crit Rev Clin Lab Sci 2016; 53:228-52. [PMID: 26743568 DOI: 10.3109/10408363.2015.1135103] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Oncophagy (cancer-related autophagy) has a complex dual character at different stages of tumor progression. It remains an important clinical problem to unravel the reasons that propel the shift in the role of oncophagy from tumor inhibition to a protective mechanism that shields full-blown malignancy. Most treatment strategies emphasize curbing protective oncophagy while triggering the oncophagy that is lethal to tumor cells. In this review, we focus on the trends in current therapeutics as well as various challenges in clinical trials to address the oncophagic dilemma and evaluate the potential of these developing therapies. A detailed analysis of the clinical and pre-clinical scenario of the anticancer medicines highlights the various inducers and inhibitors of autophagy. The ways in which tumor stage, the microenvironment and combination drug treatment continue to play an important tactical role are discussed. Moreover, autophagy targets also play a crucial role in developing the best possible solution to this oncophagy paradox. In this review, we provide a comprehensive update on the current clinical impact of autophagy-based cancer therapeutic drugs and try to lessen the gap between translational medicine and clinical science.
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Affiliation(s)
- Subhadip Mukhopadhyay
- a Department of Life Science , National Institute of Technology , Rourkela , Odisha , India
| | - Niharika Sinha
- a Department of Life Science , National Institute of Technology , Rourkela , Odisha , India
| | - Durgesh Nandini Das
- a Department of Life Science , National Institute of Technology , Rourkela , Odisha , India
| | - Prashanta Kumar Panda
- a Department of Life Science , National Institute of Technology , Rourkela , Odisha , India
| | - Prajna Paramita Naik
- a Department of Life Science , National Institute of Technology , Rourkela , Odisha , India
| | - Sujit Kumar Bhutia
- a Department of Life Science , National Institute of Technology , Rourkela , Odisha , India
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113
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Ni Z, Gong Y, Dai X, Ding W, Wang B, Gong H, Qin L, Cheng P, Li S, Lian J, He F. AU4S: a novel synthetic peptide to measure the activity of ATG4 in living cells. Autophagy 2016; 11:403-15. [PMID: 25831015 DOI: 10.1080/15548627.2015.1009773] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
ATG4 plays a key role in autophagy induction, but the methods for monitoring ATG4 activity in living cells are limited. Here we designed a novel fluorescent peptide named AU4S for noninvasive detection of ATG4 activity in living cells, which consists of the cell-penetrating peptide (CPP), ATG4-recognized sequence "GTFG," and the fluorophore FITC. Additionally, an ATG4-resistant peptide AG4R was used as a control. CPP can help AU4S or AG4R to penetrate cell membrane efficiently. AU4S but not AG4R can be recognized and cleaved by ATG4, leading to the change of fluorescence intensity. Therefore, the difference between AU4S- and AG4R-measured fluorescence values in the same sample, defined as "F-D value," can reflect ATG4 activity. By detecting the F-D values, we found that ATG4 activity paralleled LC3B-II levels in rapamycin-treated cells, but neither paralleled LC3B-II levels in starved cells nor presented a correlation with LC3B-II accumulation in WBCs from healthy donors or leukemia patients. However, when DTT was added to the system, ATG4 activity not only paralleled LC3B-II levels in starved cells in the presence or absence of autophagy inhibitors, but also presented a positive correlation with LC3B-II accumulation in WBCs from leukemia patients (R(2) = 0.5288). In conclusion, this study provides a convenient, rapid, and quantitative method to monitor ATG4 activity in living cells, which may be beneficial to basic and clinical research on autophagy.
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Key Words
- 3-MA, 3-methyladenine
- AG4R, ATG4-resistant peptide
- ATG4
- ATG4, autophagy-related 4, cysteine peptidase
- AU4S
- AU4S, autophagy-related 4 substrate
- Ac, acetyl
- CFP, cyan fluorescent protein
- CPP, cell-penetrating peptide
- CQ, chloroquine
- DTT, dithiothreitol
- EBSS, Earle's balanced salt solution
- FITC, fluorescein isothiocyanate
- HIV, human immunodeficiency virus
- LC3
- MAP1LC3/LC3, microtubule-associated protein 1 light chain 3
- NAC, N-acetyl-L-cysteine
- NRK, normal rat kidney cell line
- PAGE, polyacrylamide gel electrophoresis
- PBS, phosphate-buffered saline
- PE, phosphatidylethanolamine
- PLA2, phospholipase A2
- PMSF, phenylmethanesulfonyl fluoride
- PtdIns3K, phosphatidylinositol 3-kinase
- ROS
- ROS, reactive oxygen species
- SDS, sodium dodecyl sulfate
- WBCs, white blood cells
- YFP, yellow fluorescent protein
- autophagy
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Affiliation(s)
- Zhenhong Ni
- a Department of Biochemistry and Molecular Biology; College of Basic Medical Sciences ; Third Military Medical University ; Chongqing , China
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114
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Pan B, Chen Y, Song H, Xu Y, Wang R, Chen L. Mir-24-3p downregulation contributes to VP16-DDP resistance in small-cell lung cancer by targeting ATG4A. Oncotarget 2016; 6:317-31. [PMID: 25426560 PMCID: PMC4381597 DOI: 10.18632/oncotarget.2787] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 11/15/2014] [Indexed: 01/22/2023] Open
Abstract
Although the combination of etoposide (VP16) and cisplatin (DDP) is widely used as a first-line treatment for advanced-stage small-cell lung cancer (SCLC), chemoresistance limits its clinical use. Abnormalities of autophagy are associated with tumor chemoresistance. The present study found that miR-24-3p, a recently discovered microRNA, is significantly downregulated in VP16-DDP-resistant SCLC cells (H446/EP) compared with VP16-DDP-sensitive parent cells (H446). Forced expression of miR-24-3p sensitized H446/EP cells to VP16-DDP treatment because of a blockade of autophagic activity. We further found that downregulated miR-24-3p enhanced autophagy activation as it directly targets and inhibits autophagy-associated gene 4A (ATG4A). Overexpression of miR-24-3p into H446/EP cells led to reduction of the ATG4A protein level, allowing SCLC cells to resensitize to VP16-DDP. We conclude that miR-24-3p regulates autophagy by targeting ATG4A. Inhibition of autophagy by increasing miR-24-3p could be the basis of a strategy to prevent and treat SCLC with combination chemotherapy, particularly in chemoresistant disease.
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Affiliation(s)
- Banzhou Pan
- Department of Medical Oncology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Yitian Chen
- Department of Medical Oncology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Haizhu Song
- Department of Medical Oncology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Yichen Xu
- Department of Medical Oncology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Rui Wang
- Department of Medical Oncology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Longbang Chen
- Department of Medical Oncology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
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115
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Abstract
Autophagy plays multiple roles in the formation and progression of cancer, including both suppressive and promotive roles. It not only impacts cancer cell growth and viability directly but also has a significant role through its effects on the tumor microenvironment. Measurement of autophagy can be confusing and sometimes misleading due to the inherent difficulty of measuring both the formation and turnover of molecules involved in the autophagic process. The LC3 proteins serve as autophagosomal markers and are the basis for most of the assays used for measuring autophagy. Since each of the current assays for autophagy has significant limitations, the use of multiple assays for the analysis of autophagy in most contexts is highly advised. Here we outline three assays that are commonly used to evaluate autophagic flux in cells. These assays include the determination of LC3II formation and LC3II and p62 turnover by use of Western Blotting, quantification of LC3 puncta, and the measurement of autophagic flux using tandem labeled mCherry-GFP-LC3.
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Liu J, Fan L, Wang H, Sun G. Autophagy, a double-edged sword in anti-angiogenesis therapy. Med Oncol 2015; 33:10. [PMID: 26715036 DOI: 10.1007/s12032-015-0721-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 12/12/2015] [Indexed: 12/24/2022]
Abstract
Autophagy is a highly conservative cell behavior to keep the intracellular homeostasis and is frequently activated when cells encounter disgusting conditions, such as nutrition or growth factor deprive, hypoxia and cytotoxic agents. However, the precise role of autophagy under various conditions may be opposite, differ from protect cells survival to promote cells death, and the mechanism of this conditional-dependent role is still unclear. Anti-angiogenesis agents, such as bevacizumab, sorafenib and sunitinib, could reduce tumor microvascular density and increase tumor hypoxia, thus up-regulating autophagy activation of tumor cells, but the function of autophagy induced by anti-angiogenesis agents is still divergent and is considered to play a cytoprotective role in most cases. In this review, we mainly discuss the relationship between anti-angiogenesis therapy-induced hypoxia and autophagy, and pay special attention on the exact role of anti-angiogenesis agents induced autophagy in the process of anti-angiogenesis treatment.
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Affiliation(s)
- Jiatao Liu
- Department of Oncology, The First Affiliated Hospital of Anhui Medical University, 218 Jixi Road, Hefei, 230022, Anhui Province, China.,Department of Pharmacy, The First Affiliated Hospital of Anhui Medical University, 218 Jixi Road, Hefei, 230022, Anhui Province, China
| | - Lulu Fan
- Department of Oncology, The First Affiliated Hospital of Anhui Medical University, 218 Jixi Road, Hefei, 230022, Anhui Province, China
| | - Hua Wang
- Department of Oncology, The First Affiliated Hospital of Anhui Medical University, 218 Jixi Road, Hefei, 230022, Anhui Province, China
| | - Guoping Sun
- Department of Oncology, The First Affiliated Hospital of Anhui Medical University, 218 Jixi Road, Hefei, 230022, Anhui Province, China.
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Lefort S, Joffre C, Kieffer Y, Givel AM, Bourachot B, Zago G, Bieche I, Dubois T, Meseure D, Vincent-Salomon A, Camonis J, Mechta-Grigoriou F. Inhibition of autophagy as a new means of improving chemotherapy efficiency in high-LC3B triple-negative breast cancers. Autophagy 2015; 10:2122-42. [PMID: 25427136 DOI: 10.4161/15548627.2014.981788] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The triple-negative breast cancer (TN BC) subtype is the most aggressive form of invasive BC. Despite intensive efforts to improve BC treatments, patients with TN BC continue to exhibit poor survival, with half developing resistance to chemotherapy. Here we identify autophagy as a key mechanism in the progression and chemoresistance of a subset of TN tumors. We demonstrate that LC3B, a protein involved in autophagosome formation, is a reliable marker of poor prognosis in TN BC, validating this prognostic value at both the mRNA and protein levels in several independent cohorts. We also show that LC3B has no prognostic value for other BC subtypes (Luminal or HER2 BC), thus revealing a specific impact of autophagy on TN tumors. Autophagy is essential for the proliferative and invasive properties in 3D of TN BC cells characterized by high LC3B levels. Interestingly, the activity of the transcriptional co-activator YAP1 (Yes-associated protein 1) is regulated by the autophagy process and we identify YAP1 as a new actor in the autophagy-dependent proliferative and invasive properties of high-LC3B TN BC. Finally, inhibiting autophagy by silencing ATG5 or ATG7 significantly impaired high-LC3B TN tumor growth in vivo. Moreover, using a patient-derived TN tumor transplanted into mice, we show that an autophagy inhibitor, chloroquine, potentiates the effects of chemotherapeutic agents. Overall, our data identify LC3B as a new prognostic marker for TN BC and the inhibition of autophagy as a promising therapeutic strategy for TN BC patients.
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Key Words
- 3-dimensional culture
- 3D, 3-dimensions
- AC, adriamycin and cyclophosphamide
- ACTB, actin, β
- AP2A1/adaptin, adaptor-related protein complex 2, α 1 subunit
- ATG, autophagy-related
- BC, breast cancer
- BECN1, Beclin 1, autophagy related
- BafA1, bafilomycin A1
- Ctrl, control
- DFS, disease-free survival
- EBSS, Earle's balanced salt solution
- ERBB2/HER2, v-erb-b2 avian erythroblastic leukemia viral oncogene homolog 2
- GAPDH, glyceraldehyde-3-phosphate dehydrogenase
- HScore, histological scoring
- IHC, immunohistochemistry
- LC3B
- Lum, Luminal
- MAP1LC3B/LC3B, microtubule-associated protein one light chain 3 β
- OS, overall survival
- PDX, patient-derived xenografted tumor
- TCGA, The Cancer Genome Atlas
- TGI, tumor growth inhibition
- TN BC, triple-negative breast cancer
- YAP1
- YAP1, Yes-associated protein 1
- autophagy
- breast cancers
- i.p., intra-peritoneal
- prognosis
- response to treatment
- sem, standard error of mean
- three-MA, 3-methyladenine
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Affiliation(s)
- Sylvain Lefort
- a Laboratory of Stress and Cancer; Institut Curie ; Paris , France
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Korah J, Canaff L, Lebrun JJ. The Retinoblastoma Tumor Suppressor Protein (pRb)/E2 Promoter Binding Factor 1 (E2F1) Pathway as a Novel Mediator of TGFβ-induced Autophagy. J Biol Chem 2015; 291:2043-54. [PMID: 26598524 DOI: 10.1074/jbc.m115.678557] [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] [Received: 07/13/2015] [Indexed: 12/19/2022] Open
Abstract
TGFβ is a multifunctional cytokine that regulates cell proliferation, cell immortalization, and cell death, acting as a key homeostatic mediator in various cell types and tissues. Autophagy is a programmed mechanism that plays a pivotal role in controlling cell fate and, consequently, many physiological and pathological processes, including carcinogenesis. Although autophagy is often considered a pro-survival mechanism that renders cells viable in stressful conditions and thus might promote tumor growth, emerging evidence suggests that autophagy is also a tumor suppressor pathway. The relationship between TGFβ signaling and autophagy is context-dependent and remains unclear. TGFβ-mediated activation of autophagy has recently been suggested to contribute to the growth inhibitory effect of TGFβ in hepatocarcinoma cells. In the present study, we define a novel process of TGFβ-mediated autophagy in cancer cell lines of various origins. We found that autophagosome initiation and maturation by TGFβ is dependent on the retinoblastoma tumor suppressor protein/E2 promoter binding factor (pRb/E2F1) pathway, which we have previously established as a critical signaling axis leading to various TGFβ tumor suppressive effects. We further determined that TGFβ induces pRb/E2F1-dependent transcriptional activation of several autophagy-related genes. Together, our findings reveal that TGFβ induces autophagy through the pRb/E2F1 pathway and transcriptional activation of autophagy-related genes and further highlight the central relevance of the pRb/E2F1 pathway downstream of TGFβ signaling in tumor suppression.
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Affiliation(s)
- Juliana Korah
- From the Department of Medicine, McGill University Health Center, Cancer Research Program, Montreal, Quebec H4A 3J1, Canada
| | - Lucie Canaff
- From the Department of Medicine, McGill University Health Center, Cancer Research Program, Montreal, Quebec H4A 3J1, Canada
| | - Jean-Jacques Lebrun
- From the Department of Medicine, McGill University Health Center, Cancer Research Program, Montreal, Quebec H4A 3J1, Canada
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Katagiri H, Nakayama K, Razia S, Nakamura K, Sato E, Ishibashi T, Ishikawa M, Iida K, Ishikawa N, Otsuki Y, Nakayama S, Kyo S. Loss of autophagy-related protein Beclin 1 may define poor prognosis in ovarian clear cell carcinomas. Int J Oncol 2015; 47:2037-44. [PMID: 26458502 PMCID: PMC4665333 DOI: 10.3892/ijo.2015.3191] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 08/03/2015] [Indexed: 12/28/2022] Open
Abstract
The aim of the present study was to clarify the role of autophagy in cisplatin (CDDP) sensitivity in OCCCs and the role of Beclin 1 in OCCC progression. Autophagy was measured using: i) western blot analysis of LC3 and p62 and ii) microscopic observation of GFP-LC3 puncta. Autophagy was suppressed using chloroquine and Beclin 1 siRNA. Surgical specimens were examined for Beclin 1 protein expression by immunohistochemistry. The correlations between the loss of Beclin 1 expression and clinicopathological characteristics, prognosis and chemosensitivity were investigated. Inhibition of autophagy by chloroquine or Beclin 1 siRNA did not enhance the sensitivity of the ES2 and TOV-21G OCCC cell lines to CDDP. Loss of Beclin 1 expression was observed in 38.3% (23/60) of the analyzed tumors. There was no significant correlation between loss of Beclin 1 expression and FIGO stage, CA125 levels, patient age, status of endometriosis, Ki-67 labeling index, chemotherapy regimen or status of residual tumor. However, negative expression of Beclin 1 was associated with a shorter progression-free survival in comparison to positive Beclin 1 expression in OCCC who received cytoreductive surgery, followed by a standard platinum-based chemotherapy regimen (P=0.027, log-rank test). Beclin 1-negative tumors were no more resistant to primary adjuvant chemotherapy than were Beclin 1-positive tumors (50.0 vs. 66.7%, P=0.937). Beclin 1 knockdown using siRNA increased cell growth but not cell migration and invasion in ES2 and TOV-21G OCCC cell lines. Autophagy defects caused by loss of Beclin 1 are not related to chemoresistance and metastasis, but may be associated with malignant phenotype and poor prognosis of OCCC.
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Affiliation(s)
- Hiroshi Katagiri
- Department of Obstetrics and Gynecology, Shimane University School of Medicine, Izumo 693-8501, Japan
| | - Kentaro Nakayama
- Department of Obstetrics and Gynecology, Shimane University School of Medicine, Izumo 693-8501, Japan
| | - Sultana Razia
- Department of Obstetrics and Gynecology, Shimane University School of Medicine, Izumo 693-8501, Japan
| | - Kohei Nakamura
- Department of Obstetrics and Gynecology, Shimane University School of Medicine, Izumo 693-8501, Japan
| | - Emi Sato
- Department of Obstetrics and Gynecology, Shimane University School of Medicine, Izumo 693-8501, Japan
| | - Tomoka Ishibashi
- Department of Obstetrics and Gynecology, Shimane University School of Medicine, Izumo 693-8501, Japan
| | - Masako Ishikawa
- Department of Obstetrics and Gynecology, Shimane University School of Medicine, Izumo 693-8501, Japan
| | - Kouji Iida
- Department of Obstetrics and Gynecology, Shimane University School of Medicine, Izumo 693-8501, Japan
| | - Noriyoshi Ishikawa
- Department of Organ Pathology, Shimane University School of Medicine, Izumo 693-8501, Japan
| | - Yoshiro Otsuki
- Department of Pathology, Seirei Hamamatsu General Hospital, Hamamatsu 430-8558, Japan
| | - Satoru Nakayama
- Department of Obstetrics and Gynecology, Seirei Hamamatsu General Hospital, Hamamatsu 430-8558, Japan
| | - Satoru Kyo
- Department of Obstetrics and Gynecology, Shimane University School of Medicine, Izumo 693-8501, Japan
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Jain S, Suklabaidya S, Das B, Raghav SK, Batra SK, Senapati S. TLR4 activation by lipopolysaccharide confers survival advantage to growth factor deprived prostate cancer cells. Prostate 2015; 75:1020-33. [PMID: 25833062 DOI: 10.1002/pros.22983] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 01/23/2015] [Indexed: 02/01/2023]
Abstract
BACKGROUND Prostate cancer (PCa) cells express Toll-like receptor-4 (TLR4), a known pro-tumorigenic molecule for different cancer cells. The cancer cells residing in the avascular region of the tumor confront various metabolic stresses and continuously adapt mechanisms to overcome them. We hypothesized that TLR4 activation might provide direct survival advantage to metabolically stressed PCa cells. METHODS We first investigated the effect of LPS on survival of serum deprived PCa cells. To understand the molecular mechanisms involved in TLR4 mediated PCa survival, we next investigated change in expression of markers for apoptosis, senescence and autophagy. Ultimately, the effect of LPS on established prostate tumors was confirmed in vivo using a syngeneic rat model for PCa. RESULTS Lipopolysaccharide (LPS)-mediated TLR4 activation significantly enhanced survival of serum deprived (SD) PC3, DU145 and MAT-LyLu PCa cells. TLR4 inhibition by a specific inhibitor resulted in rapid death of SD-PC3 cells, which was significantly suppressed by LPS. Interestingly, LPS treatment suppressed macroautophagy in SD-PC3 cells and increased expression of CCL2 (C-C motif ligand-2), a known autophagy inhibitor and pro-survival factor. Intra-tumor LPS injection resulted in increased tumor mass, induced TLR4 activation, suppressed autophagy, and increased the macrophage population in MAT-LyLu-tumors. CONCLUSIONS Our study reveals that bacterial LPS enhance survival of PCa cells under conditions of nutrient stress through TLR4 activation. Moreover, LPS induces overexpression of CCL2 involved in the suppression of starvation-induced macroautophagy in PCa cells, and enhanced macrophage population in prostate tumors in vivo. Taken together, the current study suggests the importance of bacterial infection or TLR4-activation in prostate cancer pathogenesis.
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Affiliation(s)
- Sumeet Jain
- Institute of Life Sciences, Bhubaneswar, Odisha, India
- Manipal University, Manipal, Karnataka, India
| | - Sujit Suklabaidya
- Institute of Life Sciences, Bhubaneswar, Odisha, India
- Manipal University, Manipal, Karnataka, India
| | - Biswajit Das
- Institute of Life Sciences, Bhubaneswar, Odisha, India
| | | | - Surinder K Batra
- Department of Biochemistry and Molecular Biology, Buffett Cancer Center, Eppley Institute for Cancer Research, University of Nebraska Medical Center, Omaha, Nebraska
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121
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Tsun ZY, Possemato R. Amino acid management in cancer. Semin Cell Dev Biol 2015; 43:22-32. [PMID: 26277542 PMCID: PMC4800996 DOI: 10.1016/j.semcdb.2015.08.002] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 07/21/2015] [Accepted: 08/09/2015] [Indexed: 12/30/2022]
Abstract
Amino acids have a dual role in cellular metabolism, as they are both the building blocks for protein synthesis and intermediate metabolites which fuel other biosynthetic reactions. Recent work has demonstrated that deregulation of both arms of amino acid management are common alterations seen in cancer. Among the most highly consumed nutrients by cancer cells are the amino acids glutamine and serine, and the biosynthetic pathways that metabolize them are required in various cancer subtypes and the object of current efforts to target cancer metabolism. Also altered in cancer are components of the machinery which sense amino acid sufficiency, nucleated by the mechanistic target of rapamycin (mTOR), a key regulator of cell growth via modulation of key processes including protein synthesis and autophagy. The precise ways in which altered amino acid management supports cellular transformation remain mostly elusive, and a fuller mechanistic understanding of these processes will be important for efforts to exploit such alterations for cancer therapy.
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Affiliation(s)
- Zhi-Yang Tsun
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Department of Biology, Nine Cambridge Center, Cambridge, MA 02142, USA
| | - Richard Possemato
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA.
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122
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Abstract
The metabolism of malignant cells is profoundly altered in order to maintain their survival and proliferation in adverse microenvironmental conditions. Autophagy is an intracellular recycling process that maintains basal levels of metabolites and biosynthetic intermediates under starvation or other forms of stress, hence serving as an important mechanism for metabolic adaptation in cancer cells. Although it is widely acknowledged that autophagy sustains metabolism in neoplastic cells under duress, many questions remain with regard to the mutual relationship between autophagy and metabolism in cancer. Importantly, autophagy has often been described as a "double-edged sword" that can either impede or promote cancer initiation and progression. Here, we overview such a dual function of autophagy in tumorigenesis and our current understanding of the coordinated regulation of autophagy and cancer cell metabolism in the control of tumor growth, progression, and resistance to therapy.
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123
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Yang Y, Yang Y, Yang X, Zhu H, Guo Q, Chen X, Zhang H, Cheng H, Sun X. Autophagy and its function in radiosensitivity. Tumour Biol 2015; 36:4079-87. [DOI: 10.1007/s13277-015-3496-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 04/23/2015] [Indexed: 01/03/2023] Open
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124
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Liu C, DeRoo EP, Stecyk C, Wolsey M, Szuchnicki M, Hagos EG. Impaired autophagy in mouse embryonic fibroblasts null for Krüppel-like Factor 4 promotes DNA damage and increases apoptosis upon serum starvation. Mol Cancer 2015; 14:101. [PMID: 25944097 PMCID: PMC4422415 DOI: 10.1186/s12943-015-0373-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Accepted: 04/23/2015] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Autophagy is a major cellular process by which cytoplasmic components such as damaged organelles and misfolded proteins are recycled. Although low levels of autophagy occur in cells under basal conditions, certain cellular stresses including nutrient depletion, DNA damage, and oxidative stress are known to robustly induce autophagy. Krüppel-like factor 4 (KLF4) is a zinc-finger transcription factor activated during oxidative stress to maintain genomic stability. Both autophagy and KLF4 play important roles in response to stress and function in tumor suppression. METHODS To explore the role of KLF4 on autophagy in mouse embryonic fibroblasts (MEFs), we compared wild-type with Klf4 deficient cells. To determine the levels of autophagy, we starved MEFs for different times with Earle's balanced salts solution (EBSS). Rapamycin was used to manipulate mTOR activity and autophagy. The percentage of cells with γ-H2AX foci, a marker for DNA damage, and punctate pattern of GFP-LC3 were counted by confocal microscopy. The effects of the drug treatments, Klf4 overexpression, or Klf4 transient silencing on autophagy were analyzed using Western blot. Trypan Blue assay and flow cytometry were used to study cell viability and apoptosis, respectively. qPCR was also used to assay basal and the effects of Klf4 overexpression on Atg7 expression levels. RESULTS Here our data suggested that Klf4 (-/-) MEFs exhibited impaired autophagy, which sensitized them to cell death under nutrient deprivation. Secondly, DNA damage in Klf4-null MEFs increased after treatment with EBSS and was correlated with increased apoptosis. Thirdly, we found that Klf4 (-/-) MEFs showed hyperactive mTOR activity. Furthermore, we demonstrated that rapamycin reduced the increased level of mTOR in Klf4 (-/-) MEFs, but did not restore the level of autophagy. Finally, re-expression of Klf4 in Klf4 deficient MEFs resulted in increased levels of LC3II, a marker for autophagy, and Atg7 expression level when compared to GFP-control transfected Klf4 (-/-) MEFs. CONCLUSION Taken together, our results strongly suggest that KLF4 plays a critical role in the regulation of autophagy and suppression of mTOR activity. In addition, we showed that rapamycin decreased the level of mTOR in Klf4 (-/-) MEFs, but did not restore autophagy. This suggests that KLF4 regulates autophagy through both mTOR-dependent and independent mechanisms. Furthermore, for the first time, our findings provide novel insights into the mechanism by which KLF4 perhaps prevents DNA damage and apoptosis through activation of autophagy.
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Affiliation(s)
- Changchang Liu
- Department of Biology, Colgate University, 13 Oak Dr., Olin Hall 205A, Hamilton, NY, 13346, USA.
| | - Elise P DeRoo
- Department of Biology, Colgate University, 13 Oak Dr., Olin Hall 205A, Hamilton, NY, 13346, USA. .,Program in Cellular and Molecular Medicine, Boston Childrens Hospital, Boston, MA, 02115, USA. .,School of Medical School, Harvard University, Boston, MA, 02115, USA.
| | - Catherine Stecyk
- Department of Biology, Colgate University, 13 Oak Dr., Olin Hall 205A, Hamilton, NY, 13346, USA. .,Cummings School of Veterinary Medicine, Tufts University, North Grafton, MA, 01536, USA.
| | - Margaret Wolsey
- Department of Biology, Colgate University, 13 Oak Dr., Olin Hall 205A, Hamilton, NY, 13346, USA.
| | - Mateusz Szuchnicki
- Department of Biology, Colgate University, 13 Oak Dr., Olin Hall 205A, Hamilton, NY, 13346, USA.
| | - Engda G Hagos
- Department of Biology, Colgate University, 13 Oak Dr., Olin Hall 205A, Hamilton, NY, 13346, USA.
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125
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Wang S, Xia P, Rehm M, Fan Z. Autophagy and cell reprogramming. Cell Mol Life Sci 2015; 72:1699-713. [PMID: 25572296 PMCID: PMC11113636 DOI: 10.1007/s00018-014-1829-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 12/23/2014] [Accepted: 12/30/2014] [Indexed: 12/17/2022]
Abstract
Autophagy is an evolutionarily conserved process that degrades cytoplasmic components, thus contributing to cell survival and tissue homeostasis. Recent studies have demonstrated that autophagy maintains stem cells in relatively undifferentiated states (stemness) and also contributes to differentiation processes. Autophagy likewise plays a crucial role in somatic cell reprogramming, a finely regulated process that resets differentiated cells to a pluripotent state and that requires comprehensive alterations in transcriptional activities and epigenetic signatures. Autophagy assists in manifesting the functional consequences that arise from these alterations by modifying cellular protein expression profiles. The role of autophagy appears to be particularly relevant for early phases of cell reprogramming during the generation of induced pluripotent stems cells (iPSCs). In this review, we provide an overview of the core molecular machinery that constitutes the autophagic degradation system, describe the roles of autophagy in maintenance, self-renewal, and differentiation of stem cells, and discuss the autophagic process and its regulation during cell reprogramming.
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Affiliation(s)
- Shuo Wang
- CAS Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101 China
| | - Pengyan Xia
- CAS Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101 China
| | - Markus Rehm
- Department of Physiology and Medical Physics, Centre for Systems Medicine, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Zusen Fan
- CAS Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101 China
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Kyöstilä K, Syrjä P, Jagannathan V, Chandrasekar G, Jokinen TS, Seppälä EH, Becker D, Drögemüller M, Dietschi E, Drögemüller C, Lang J, Steffen F, Rohdin C, Jäderlund KH, Lappalainen AK, Hahn K, Wohlsein P, Baumgärtner W, Henke D, Oevermann A, Kere J, Lohi H, Leeb T. A missense change in the ATG4D gene links aberrant autophagy to a neurodegenerative vacuolar storage disease. PLoS Genet 2015; 11:e1005169. [PMID: 25875846 PMCID: PMC4398399 DOI: 10.1371/journal.pgen.1005169] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 03/20/2015] [Indexed: 11/22/2022] Open
Abstract
Inherited neurodegenerative disorders are debilitating diseases that occur across different species. We have performed clinical, pathological and genetic studies to characterize a novel canine neurodegenerative disease present in the Lagotto Romagnolo dog breed. Affected dogs suffer from progressive cerebellar ataxia, sometimes accompanied by episodic nystagmus and behavioral changes. Histological examination revealed unique pathological changes, including profound neuronal cytoplasmic vacuolization in the nervous system, as well as spheroid formation and cytoplasmic aggregation of vacuoles in secretory epithelial tissues and mesenchymal cells. Genetic analyses uncovered a missense change, c.1288G>A; p.A430T, in the autophagy-related ATG4D gene on canine chromosome 20 with a highly significant disease association (p = 3.8 x 10-136) in a cohort of more than 2300 Lagotto Romagnolo dogs. ATG4D encodes a poorly characterized cysteine protease belonging to the macroautophagy pathway. Accordingly, our histological analyses indicated altered autophagic flux in affected tissues. The knockdown of the zebrafish homologue atg4da resulted in a widespread developmental disturbance and neurodegeneration in the central nervous system. Our study describes a previously unknown canine neurological disease with particular pathological features and implicates the ATG4D protein as an important autophagy mediator in neuronal homeostasis. The canine phenotype serves as a model to delineate the disease-causing pathological mechanism(s) and ATG4D function, and can also be used to explore treatment options. Furthermore, our results reveal a novel candidate gene for human neurodegeneration and enable the development of a genetic test for veterinary diagnostic and breeding purposes. Neurodegenerative disorders affect millions of people worldwide. We describe a novel neurodegenerative disease in a canine model, characterized by progressive cerebellar ataxia and cellular vacuolization. Our genetic analyses identified a single nucleotide change in the autophagy-related ATG4D gene in affected dogs. The ATG4D gene has not been linked to inherited diseases before. The autophagy-lysosome pathway plays an important role in degrading and recycling different cellular components. Disturbed autophagy has been reported in several different diseases but mutations in core autophagy components are rare. Histological analyses of affected canine brain tissues revealed altered autophagic flux, and a knockdown of the gene in the zebrafish model caused marked neurodevelopmental alterations and neurodegeneration. Our findings identify a new disease-causing pathway and implicate the ATG4D protease as an important mediator for neuronal homeostasis. Furthermore, our study establishes a large animal model to investigate the role of ATG4D in autophagy and to test possible treatment options.
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Affiliation(s)
- Kaisa Kyöstilä
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- Department of Molecular Genetics, Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Pernilla Syrjä
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | - Vidhya Jagannathan
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | | | - Tarja S. Jokinen
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland
| | - Eija H. Seppälä
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- Department of Molecular Genetics, Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Doreen Becker
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | | | - Elisabeth Dietschi
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Cord Drögemüller
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Johann Lang
- Department of Clinical Veterinary Medicine, Division of Clinical Radiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Frank Steffen
- Neurology Service, Department of Small Animals, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Cecilia Rohdin
- University Animal Hospital, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Karin H. Jäderlund
- Department of Companion Animal Clinical Sciences, Norwegian University of Life Sciences, Oslo, Norway
| | - Anu K. Lappalainen
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland
| | - Kerstin Hahn
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Peter Wohlsein
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Wolfgang Baumgärtner
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Diana Henke
- Division of Neurological Sciences, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Anna Oevermann
- Division of Neurological Sciences, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Juha Kere
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- Department of Molecular Genetics, Folkhälsan Institute of Genetics, Helsinki, Finland
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
- Science for Life Laboratory, Karolinska Institutet, Solna, Sweden
| | - Hannes Lohi
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- Department of Molecular Genetics, Folkhälsan Institute of Genetics, Helsinki, Finland
- * E-mail:
| | - Tosso Leeb
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
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127
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Galluzzi L, Pietrocola F, Bravo-San Pedro JM, Amaravadi RK, Baehrecke EH, Cecconi F, Codogno P, Debnath J, Gewirtz DA, Karantza V, Kimmelman A, Kumar S, Levine B, Maiuri MC, Martin SJ, Penninger J, Piacentini M, Rubinsztein DC, Simon HU, Simonsen A, Thorburn AM, Velasco G, Ryan KM, Kroemer G. Autophagy in malignant transformation and cancer progression. EMBO J 2015; 34:856-80. [PMID: 25712477 PMCID: PMC4388596 DOI: 10.15252/embj.201490784] [Citation(s) in RCA: 907] [Impact Index Per Article: 100.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 01/14/2015] [Accepted: 01/16/2015] [Indexed: 12/15/2022] Open
Abstract
Autophagy plays a key role in the maintenance of cellular homeostasis. In healthy cells, such a homeostatic activity constitutes a robust barrier against malignant transformation. Accordingly, many oncoproteins inhibit, and several oncosuppressor proteins promote, autophagy. Moreover, autophagy is required for optimal anticancer immunosurveillance. In neoplastic cells, however, autophagic responses constitute a means to cope with intracellular and environmental stress, thus favoring tumor progression. This implies that at least in some cases, oncogenesis proceeds along with a temporary inhibition of autophagy or a gain of molecular functions that antagonize its oncosuppressive activity. Here, we discuss the differential impact of autophagy on distinct phases of tumorigenesis and the implications of this concept for the use of autophagy modulators in cancer therapy.
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Affiliation(s)
- Lorenzo Galluzzi
- Equipe 11 labellisée pas la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France INSERM U1138, Paris, France Gustave Roussy Cancer Campus, Villejuif, France Université Paris Descartes Sorbonne Paris Cité, Paris, France
| | - Federico Pietrocola
- Equipe 11 labellisée pas la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France INSERM U1138, Paris, France Gustave Roussy Cancer Campus, Villejuif, France
| | - José Manuel Bravo-San Pedro
- Equipe 11 labellisée pas la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France INSERM U1138, Paris, France Gustave Roussy Cancer Campus, Villejuif, France
| | - Ravi K Amaravadi
- Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA, USA
| | - Eric H Baehrecke
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Francesco Cecconi
- Cell Stress and Survival Unit, Danish Cancer Society Research Center, Copenhagen, Denmark IRCCS Fondazione Santa Lucia and Department of Biology University of Rome Tor Vergata, Rome, Italy
| | - Patrice Codogno
- Université Paris Descartes Sorbonne Paris Cité, Paris, France Institut Necker Enfants-Malades (INEM), Paris, France INSERM U1151, Paris, France CNRS UMR8253, Paris, France
| | - Jayanta Debnath
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
| | - David A Gewirtz
- Department of Pharmacology, Toxicology and Medicine, Virginia Commonwealth University, Richmond Virginia, VA, USA
| | | | - Alec Kimmelman
- Division of Genomic Stability and DNA Repair, Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Sharad Kumar
- Centre for Cancer Biology, University of South Australia, Adelaide, SA, Australia
| | - Beth Levine
- Center for Autophagy Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, USA Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Maria Chiara Maiuri
- Equipe 11 labellisée pas la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France INSERM U1138, Paris, France Gustave Roussy Cancer Campus, Villejuif, France
| | - Seamus J Martin
- Department of Genetics, Trinity College, The Smurfit Institute, Dublin, Ireland
| | - Josef Penninger
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - Mauro Piacentini
- Department of Biology, University of Rome Tor Vergata, Rome, Italy National Institute for Infectious Diseases IRCCS 'Lazzaro Spallanzani', Rome, Italy
| | - David C Rubinsztein
- Department of Medical Genetics, Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Anne Simonsen
- Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Andrew M Thorburn
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Guillermo Velasco
- Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University of Madrid, Madrid, Spain Instituto de Investigaciones Sanitarias San Carlos (IdISSC), Madrid, Spain
| | - Kevin M Ryan
- Cancer Research UK Beatson Institute, Glasgow, UK
| | - Guido Kroemer
- Equipe 11 labellisée pas la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France INSERM U1138, Paris, France Université Paris Descartes Sorbonne Paris Cité, Paris, France Pôle de Biologie, Hôpital Européen Georges Pompidou, AP-HP, Paris, France Metabolomics and Cell Biology Platforms, Gustave Roussy Cancer Campus, Villejuif, France
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128
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Yang X, Yu DD, Yan F, Jing YY, Han ZP, Sun K, Liang L, Hou J, Wei LX. The role of autophagy induced by tumor microenvironment in different cells and stages of cancer. Cell Biosci 2015; 5:14. [PMID: 25844158 PMCID: PMC4384293 DOI: 10.1186/s13578-015-0005-2] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Accepted: 03/13/2015] [Indexed: 12/13/2022] Open
Abstract
Development of a tumor is a very complex process, and invasion and metastasis of malignant tumors are hallmarks and are difficult problems to overcome. The tumor microenvironment plays an important role in controlling tumor fate and autophagy induced by the tumor microenvironment is attracting more and more attention. Autophagy can be induced by several stressors in the tumor microenvironment and autophagy modifies the tumor microenvironment, too. Autophagy has dual roles in tumor growth. In this review, we discussed the interaction between autophagy and the tumor microenvironment and the paradoxical roles of autophagy on tumor growth at different stages of tumor development.
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Affiliation(s)
- Xue Yang
- Tumor Immunology and Gene Therapy Center, Eastern Hepatobiliary Surgery Hospital, The Second Military Medical University, 225 Changhai Road, 200438 Shanghai, China
| | - Dan-Dan Yu
- Tumor Immunology and Gene Therapy Center, Eastern Hepatobiliary Surgery Hospital, The Second Military Medical University, 225 Changhai Road, 200438 Shanghai, China
| | - Fei Yan
- Tumor Immunology and Gene Therapy Center, Eastern Hepatobiliary Surgery Hospital, The Second Military Medical University, 225 Changhai Road, 200438 Shanghai, China
| | - Ying-Ying Jing
- Tumor Immunology and Gene Therapy Center, Eastern Hepatobiliary Surgery Hospital, The Second Military Medical University, 225 Changhai Road, 200438 Shanghai, China
| | - Zhi-Peng Han
- Tumor Immunology and Gene Therapy Center, Eastern Hepatobiliary Surgery Hospital, The Second Military Medical University, 225 Changhai Road, 200438 Shanghai, China
| | - Kai Sun
- Central laboratory, Ren Ji Hospital, School of Medicine, Shanghai JiaoTong University, Shanghai, China
| | - Lei Liang
- Tumor Immunology and Gene Therapy Center, Eastern Hepatobiliary Surgery Hospital, The Second Military Medical University, 225 Changhai Road, 200438 Shanghai, China
| | - Jing Hou
- Department of Pharmacy, Chang Hai Hospital, The Second Military Medical University, Shanghai, China
| | - Li-Xin Wei
- Tumor Immunology and Gene Therapy Center, Eastern Hepatobiliary Surgery Hospital, The Second Military Medical University, 225 Changhai Road, 200438 Shanghai, China
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129
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Roles of autophagy induced by natural compounds in prostate cancer. BIOMED RESEARCH INTERNATIONAL 2015; 2015:121826. [PMID: 25821782 PMCID: PMC4364006 DOI: 10.1155/2015/121826] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 12/23/2014] [Indexed: 02/07/2023]
Abstract
Autophagy is a homeostatic mechanism through which intracellular organelles and proteins are degraded and recycled in response to increased metabolic demand or stress. Autophagy dysfunction is often associated with many diseases, including cancer. Because of its role in tumorigenesis, autophagy can represent a new therapeutic target for cancer treatment.
Prostate cancer (PCa) is one of the most common cancers in aged men. The evidence on alterations of autophagy related genes and/or protein levels in PCa cells suggests a potential implication of autophagy in PCa onset and progression. The use of natural compounds, characterized by low toxicity to normal tissue associated with specific anticancer effects at physiological levels in vivo, is receiving increasing attention for prevention and/or treatment of PCa. Understanding the mechanism of action of these compounds could be crucial for the development of new therapeutic or chemopreventive options. In this review we focus on the current evidence showing the capacity of natural compounds to exert their action through autophagy modulation in PCa cells.
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130
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Panda PK, Mukhopadhyay S, Das DN, Sinha N, Naik PP, Bhutia SK. Mechanism of autophagic regulation in carcinogenesis and cancer therapeutics. Semin Cell Dev Biol 2015; 39:43-55. [PMID: 25724561 DOI: 10.1016/j.semcdb.2015.02.013] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 02/12/2015] [Accepted: 02/19/2015] [Indexed: 12/15/2022]
Abstract
Autophagy in cancer is an intensely debated concept in the field of translational research. The dual nature of autophagy implies that it can potentially modulate the pro-survival and pro-death mechanisms in tumor initiation and progression. There is a prospective molecular relationship between defective autophagy and tumorigenesis that involves the accumulation of damaged mitochondria and protein aggregates, which leads to the production of reactive oxygen species (ROS) and ultimately causes DNA damage that can lead to genomic instability. Moreover, autophagy regulates necrosis and is followed by inflammation, which limits tumor metastasis. On the other hand, autophagy provides a survival advantage to detached, dormant metastatic cells through nutrient fueling by tumor-associated stromal cells. Manipulating autophagy for induction of cell death, inhibition of protective autophagy at tissue-and context-dependent for apoptosis modulation has therapeutic implications. This review presents a comprehensive overview of the present state of knowledge regarding autophagy as a new approach to treat cancer.
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Affiliation(s)
- Prashanta Kumar Panda
- Department of Life Science, National Institute of Technology Rourkela, Odisha, India
| | - Subhadip Mukhopadhyay
- Department of Life Science, National Institute of Technology Rourkela, Odisha, India
| | - Durgesh Nandini Das
- Department of Life Science, National Institute of Technology Rourkela, Odisha, India
| | - Niharika Sinha
- Department of Life Science, National Institute of Technology Rourkela, Odisha, India
| | - Prajna Paramita Naik
- Department of Life Science, National Institute of Technology Rourkela, Odisha, India
| | - Sujit K Bhutia
- Department of Life Science, National Institute of Technology Rourkela, Odisha, India.
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131
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Abstract
Autophagy is a catabolic degradation process in which cellular proteins and
organelles are engulfed by double-membrane autophagosomes and degraded in lysosomes.
Autophagy has emerged as a critical pathway in tumor development and cancer therapy,
although its precise function remains a conundrum. The current consensus is that
autophagy has a dual role in cancer. On the one hand, autophagy functions as a tumor
suppressor mechanism by preventing the accumulation of damaged organelles and
aggregated proteins. On the other hand, autophagy is a key cell survival mechanism
for established tumors; therefore autophagy inhibition suppresses tumor progression.
Here, we summarize recent progress on the role of autophagy in tumorigenesis and
cancer therapy.
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Affiliation(s)
- Xiaoyong Zhi
- Center for Autophagy Research, Department of
Internal Medicine, University of Texas Southwestern Medical
CenterDallas, Texas
75390USA
| | - Qing Zhong
- Department of Biochemistry, University of
Texas Southwestern Medical CenterDallas, Texas
75390USA
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132
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Tian Y, Wang L, Ou JHJ. Autophagy, a double-edged sword in hepatocarcinogenesis. Mol Cell Oncol 2015; 2:e1004968. [PMID: 27308502 PMCID: PMC4905348 DOI: 10.1080/23723556.2015.1004968] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 12/31/2014] [Accepted: 01/02/2015] [Indexed: 11/26/2022]
Abstract
Autophagy has opposite effects on hepatocarcinogenesis depending on whether it occurs before or after its onset. Autophagy prevents the initiation of hepatocarcinogenesis by suppressing oxidative stress and DNA damage. However, it also inhibits cell death and the expression of tumor suppressors to promote tumor progression once hepatocarcinogenesis has been initiated.
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Affiliation(s)
- Yongjun Tian
- Department of Molecular Microbiology and Immunology; University of Southern California Keck School of Medicine ; Los Angeles, CA, USA
| | - Linya Wang
- Department of Molecular Microbiology and Immunology; University of Southern California Keck School of Medicine ; Los Angeles, CA, USA
| | - Jing-Hsiung James Ou
- Department of Molecular Microbiology and Immunology; University of Southern California Keck School of Medicine ; Los Angeles, CA, USA
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133
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Teaching the basics of autophagy and mitophagy to redox biologists--mechanisms and experimental approaches. Redox Biol 2015; 4:242-59. [PMID: 25618581 PMCID: PMC4803799 DOI: 10.1016/j.redox.2015.01.003] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 12/24/2014] [Accepted: 01/01/2015] [Indexed: 02/08/2023] Open
Abstract
Autophagy is a lysosomal mediated degradation activity providing an essential mechanism for recycling cellular constituents, and clearance of excess or damaged lipids, proteins and organelles. Autophagy involves more than 30 proteins and is regulated by nutrient availability, and various stress sensing signaling pathways. This article provides an overview of the mechanisms and regulation of autophagy, its role in health and diseases, and methods for its measurement. Hopefully this teaching review together with the graphic illustrations will be helpful for instructors teaching graduate students who are interested in grasping the concepts and major research areas and introducing recent developments in the field. mTOR, Beclin–VPS34, LC3 homologs, and adaptor proteins in autophagy. Autophagosomal membranes may derive from multiple sources. Autophagosomal–lysosomal fusion contributes to the control of autophagic flux. Assess autophagy by autophagosomal and protein turnover, and morphological alterations. Autophagy adysfunction in cancer, aging, neurodegeneration and infection.
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134
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Fernández ÁF, López-Otín C. The functional and pathologic relevance of autophagy proteases. J Clin Invest 2015; 125:33-41. [PMID: 25654548 DOI: 10.1172/jci73940] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Autophagy is a well-conserved catabolic process essential for cellular homeostasis. First described in yeast as an adaptive response to starvation, this pathway is also present in higher eukaryotes, where it is triggered by stress signals such as damaged organelles or pathogen infection. Autophagy is characterized at the cellular level by the engulfment of portions of the cytoplasm in double-membrane structures called autophagosomes. Autophagosomes fuse with lysosomes, resulting in degradation of the inner autophagosomal membrane and luminal content. This process is coordinated by complex molecular systems, including the ATG8 ubiquitin-like conjugation system and the ATG4 cysteine proteases, which are implicated in the formation, elongation, and fusion of these autophagic vesicles. In this Review, we focus on the diverse functional roles of the autophagins, a protease family formed by the four mammalian orthologs of yeast Atg4. We also address the dysfunctional expression of these proteases in several pathologic conditions such as cancer and inflammation and discuss potential therapies based on their modulation.
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135
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Tian Y, Kuo CF, Sir D, Wang L, Govindarajan S, Petrovic LM, Ou JHJ. Autophagy inhibits oxidative stress and tumor suppressors to exert its dual effect on hepatocarcinogenesis. Cell Death Differ 2014; 22:1025-34. [PMID: 25526090 DOI: 10.1038/cdd.2014.201] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 10/05/2014] [Accepted: 11/05/2014] [Indexed: 12/29/2022] Open
Abstract
The role of autophagy in carcinogenesis is controversial and apparently complex. By using mice with hepatocyte-specific knockout of Atg5, a gene essential for autophagy, we longitudinally studied the role of autophagy in hepatocarcinogenesis. We found that impairing autophagy in hepatocytes would induce oxidative stress and DNA damage, followed by the initiation of hepatocarcinogenesis, which could be suppressed by the antioxidant N-acetylcysteine. Interestingly, these mice developed only benign tumors with no hepatocellular carcinoma (HCC), even after the treatment with diethylnitrosamine, which induced HCC in wild-type mice. The inability of mice to develop HCC when autophagy was impaired was associated with the induction of multiple tumor suppressors including p53. Further analysis indicated that the induction of p53 was associated with the DNA-damage response. Tumorigenesis studies using an established liver tumor cell line confirmed a positive role of autophagy in tumorigenesis and a negative role of p53 in this process when autophagy was impaired. Our studies thus demonstrate that autophagy is required to maintain healthy mitochondria and to reduce oxidative stress and DNA damage to prevent the initiation of hepatocarcinogenesis. However, once hepatocarcinogenesis has been initiated, its presence is also required to suppress the expression of tumor suppressors to promote the development of HCC.
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Affiliation(s)
- Y Tian
- Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
| | - C-F Kuo
- Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
| | - D Sir
- Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
| | - L Wang
- Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
| | - S Govindarajan
- 1] Department of Pathology, University of Southern California Keck School of Medicine, Los Angeles, CA, USA [2] Rancho Los Amigos Rehabilitation Center, Downey, CA, USA
| | - L M Petrovic
- Department of Pathology, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
| | - J-H J Ou
- Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
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136
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AMBRA1 links autophagy to cell proliferation and tumorigenesis by promoting c-Myc dephosphorylation and degradation. Nat Cell Biol 2014; 17:20-30. [PMID: 25438055 PMCID: PMC4976803 DOI: 10.1038/ncb3072] [Citation(s) in RCA: 166] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Accepted: 10/23/2014] [Indexed: 02/06/2023]
Abstract
Inhibition of a main regulator of cell metabolism, the protein kinase mTOR, induces autophagy and inhibits cell proliferation. However, the molecular pathways involved in the cross-talk between these two mTOR-dependent cell processes are largely unknown. Here we show that the scaffold protein AMBRA1, a member of the autophagy signalling network and a downstream target of mTOR, regulates cell proliferation by facilitating the dephosphorylation and degradation of the proto-oncogene C-MYC. We found that AMBRA1 favors the interaction between C-MYC and its phosphatase PP2A and that, when mTOR is inhibited, it enhances PP2A activity on this specific target, thereby reducing the cell division rate. As expected, such a de-regulation of C-MYC correlates with increased tumorigenesis in AMBRA1-defective systems, thus supporting a role for AMBRA1 as a haploinsufficient tumour suppressor gene.
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137
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Popovic D, Vucic D, Dikic I. Ubiquitination in disease pathogenesis and treatment. Nat Med 2014; 20:1242-53. [PMID: 25375928 DOI: 10.1038/nm.3739] [Citation(s) in RCA: 828] [Impact Index Per Article: 82.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 09/29/2014] [Indexed: 02/07/2023]
Abstract
Ubiquitination is crucial for a plethora of physiological processes, including cell survival and differentiation and innate and adaptive immunity. In recent years, considerable progress has been made in the understanding of the molecular action of ubiquitin in signaling pathways and how alterations in the ubiquitin system lead to the development of distinct human diseases. Here we describe the role of ubiquitination in the onset and progression of cancer, metabolic syndromes, neurodegenerative diseases, autoimmunity, inflammatory disorders, infection and muscle dystrophies. Moreover, we indicate how current knowledge could be exploited for the development of new clinical therapies.
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Affiliation(s)
- Doris Popovic
- 1] Institute of Biochemistry II, Goethe University School of Medicine, University Hospital, Frankfurt, Germany. [2] Buchmann Institute for Molecular Life Sciences, Goethe University School of Medicine, University Hospital, Frankfurt, Germany
| | - Domagoj Vucic
- Department of Early Discovery Biochemistry, Genentech, Inc., South San Francisco, California, USA
| | - Ivan Dikic
- 1] Institute of Biochemistry II, Goethe University School of Medicine, University Hospital, Frankfurt, Germany. [2] Buchmann Institute for Molecular Life Sciences, Goethe University School of Medicine, University Hospital, Frankfurt, Germany. [3] Department of Immunology, University of Split School of Medicine, Split, Croatia
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138
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Akin D, Wang SK, Habibzadegah-Tari P, Law B, Ostrov D, Li M, Yin XM, Kim JS, Horenstein N, Dunn WA. A novel ATG4B antagonist inhibits autophagy and has a negative impact on osteosarcoma tumors. Autophagy 2014; 10:2021-35. [PMID: 25483883 PMCID: PMC4502682 DOI: 10.4161/auto.32229] [Citation(s) in RCA: 174] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Autophagy has been implicated in the progression and chemoresistance of various cancers. In this study, we have shown that osteosarcoma Saos-2 cells lacking ATG4B, a cysteine proteinase that activates LC3B, are defective in autophagy and fail to form tumors in mouse models. By combining in silico docking with in vitro and cell-based assays, we identified small compounds that suppressed starvation-induced protein degradation, LC3B lipidation, and formation of autophagic vacuoles. NSC185058 effectively inhibited ATG4B activity in vitro and in cells while having no effect on MTOR and PtdIns3K activities. In addition, this ATG4B antagonist had a negative impact on the development of Saos-2 osteosarcoma tumors in vivo. We concluded that tumor suppression was due to a reduction in ATG4B activity, since we found autophagy suppressed within treated tumors and the compound had no effects on oncogenic protein kinases. Our findings demonstrate that ATG4B is a suitable anti-autophagy target and a promising therapeutic target to treat osteosarcoma.
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Key Words
- 3MA, 3-methyladenine
- ACTB, actin, beta
- ATG, autophagy-related
- ATG4B
- ATG4B, autophagy-related 4B, cysteine protease
- AV, autophagic vacuole
- BECN1, beclin 1, autophagy related
- CMPase, cytidine monophosphatase
- DMEM, Dulbecco's modified Eagle medium
- ECL, enhanced chemiluminescence
- FYVE, zinc-finger domain named after 4 cysteine-rich proteins: FAB1, YOTB, VAC1, and EEA1
- GABARAPL2, GABA(A) receptor-associated protein-like 2
- GFP, green fluorescent protein
- GST, glutathione S-transferase
- HRP, horseradish peroxidase
- IC50, half maximal inhibitory concentration
- IP, intraperitoneal
- LC3B
- MAP1LC3B/LC3B, microtubule-associated protein 1 light chain 3beta
- MP, melting point
- MTOR, mechanistic target of rapamycin
- NCI, National Cancer Institute
- NMR, nuclear magnetic resonance
- PLA2, phospholipase A2
- PVDF, polyvinylidene difluoride
- PtdIns3K, phosphatidylinositol 3-kinase class III
- PtdIns3P, phosphatidylinositol 3-phosphate
- RFP, red fluorescent protein
- RLU, relative luciferase units
- RPS6, ribosomal protein S6
- RPS6KB1, ribosomal protein S6 kinase, 70kDa, polypeptide 1
- SEM, standard error of the mean
- ULK1/2, unc-51-like autophagy activating kinase 1/2
- and xenografts
- antiautophagy compounds
- dNGLUC, Gaussia luciferase
- in silico docking
- osteosarcoma
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Affiliation(s)
- Debra Akin
- a Department of Anatomy and Cell Biology ; University of Florida ; Gainesville , FL USA
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139
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Cicchini M, Chakrabarti R, Kongara S, Price S, Nahar R, Lozy F, Zhong H, Vazquez A, Kang Y, Karantza V. Autophagy regulator BECN1 suppresses mammary tumorigenesis driven by WNT1 activation and following parity. Autophagy 2014; 10:2036-52. [PMID: 25483966 PMCID: PMC4502817 DOI: 10.4161/auto.34398] [Citation(s) in RCA: 117] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Earlier studies reported allelic deletion of the essential autophagy regulator BECN1 in breast cancers implicating BECN1 loss, and likely defective autophagy, in tumorigenesis. Recent studies have questioned the tumor suppressive role of autophagy, as autophagy-related gene (Atg) defects generally suppress tumorigenesis in well-characterized mouse tumor models. We now report that, while it delays or does not alter mammary tumorigenesis driven by Palb2 loss or ERBB2 and PyMT overexpression, monoallelic Becn1 loss promotes mammary tumor development in 2 specific contexts, namely following parity and in association with wingless-type MMTV integration site family, member 1 (WNT1) activation. Our studies demonstrate that Becn1 heterozygosity, which results in immature mammary epithelial cell expansion and aberrant TNFRSF11A/TNR11/RANK (tumor necrosis factor receptor superfamily, member 11a, NFKB activator) signaling, promotes mammary tumorigenesis in multiparous FVB/N mice and in cooperation with the progenitor cell-transforming WNT1 oncogene. Similar to our Becn1(+/-);MMTV-Wnt1 mouse model, low BECN1 expression and an activated WNT pathway gene signature correlate with the triple-negative subtype, TNFRSF11A axis activation and poor prognosis in human breast cancers. Our results suggest that BECN1 may have nonautophagy-related roles in mammary development, provide insight in the seemingly paradoxical roles of BECN1 in tumorigenesis, and constitute the basis for further studies on the pathophysiology and treatment of clinically aggressive triple negative breast cancers (TNBCs).
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Key Words
- 8-O-dG, 8-oxo-7, 8-dihydroguanine
- ATG, autophagy-related
- BECN1, Beclin 1, autophagy-related
- BSA, bovine serum albumin
- Beclin 1
- CASP3, caspase 3
- CD24, cluster of differentiation 24
- DAPI, 4′, 6-diamidino-2-phenylindole
- DFS, disease-free survival
- DMEM, Dulbecco's modified Eagle's medium
- E, 17b-estradiol
- EGF, epidermal growth factor
- EGFP, enhanced green fluorescent protein
- EGFR/ERBB1, epidermal growth factor receptor
- EM, electron microscopy
- EMT, epithelial-to-mesenchymal transition
- ERBB2, v-erb-b2 avian erythroblastic leukemia viral oncogene homolog 2
- ESR1, estrogen receptor 1
- FACS, fluorescence activated cell sorting
- FGF2/bFGF, fibroblast growth factor 2 (basic)
- GSEA, gene set enrichment analysis
- H&E, hematoxylin &, eosin
- HR, hormone receptor
- IF, immunofluorescence
- IHC, immunohistochemistry
- IL, interleukin
- ITGB1/CD29, Integrin, beta 1 (fibronectin receptor beta polypeptide, antigen CD29 includes MDF2, MSK12)
- ITGB3/CD61, integrin, beta 3 (platelet glycoprotein IIIa, antigen CD61)
- KRT, keratin
- Keratin 6
- LIN−, lineage negative (CD31− CD45− LY76−)
- LY76/TER119, lymphocyte antigen 76
- MAP1LC3B/LC3B, microtubule-associated protein 1 light chain 3 beta
- MEC, mammary epithelial cell
- MEGM, mammary epithelial growth medium
- MGs, mammary glands
- MKI67, marker of proliferation Ki-67
- MMTV, mouse mammary tumor virus
- MaPC, mammary progenitor cell
- MaSC, mammary stem cell
- NFKB
- NFKB/NFkB, nuclear factor of kappa light polypeptide gene enhancer in B-cells
- PBS, phosphate-buffered saline
- PECAM1/CD31, platelet/endothelial cell adhesion molecule 1
- PGR, progesterone receptor
- PI, propidium iodide
- PTPRC/CD45, protein tyrosine phosphatase, receptor type, C
- RELA/P65, v-rel avian reticuloendotheliosis viral oncogene homolog a
- ROS, reactive oxygen species
- SD, standard deviation
- SNPs, single nucleotide polymorphisms
- SQSTM1/p62, sequestosome1
- TEBs, terminal end buds
- TNBC
- TNBCs, triple-negative breast cancers
- TNF, tumor necrosis factor
- TNF11
- TNFRSF11A
- TNFRSF11A/TNR11/RANK, tumor necrosis factor receptor superfamily, member 11a, NFKB activator
- TNFSF11
- TNFSF11/TNF11/RANKL, tumor necrosis factor (ligand) superfamily, member 11
- TNR11
- TP53 (TRP53 in mice), tumor protein p53 (transformation related protein 53 in mice)
- WNT1
- WNT1, wingless-Type MMTV integration site family, member 1
- basal-like breast cancer
- iMMECs, immortalized mouse mammary epithelial cells
- p-KRT8/p-K8, phosphorylated Keratin 8
- parity
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140
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Autophagy as a pro-death pathway. Immunol Cell Biol 2014; 93:35-42. [PMID: 25331550 DOI: 10.1038/icb.2014.85] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 09/01/2014] [Accepted: 09/08/2014] [Indexed: 12/12/2022]
Abstract
The evolutionarily conserved catabolic process of autophagy involves the degradation of cytoplasmic components through lysosomal enzymes. Basal levels of autophagy maintain cellular homeostasis and under stress conditions high levels of autophagy are induced. It is often under such stress conditions that high levels of autophagy and cell death have been observed, leading to the idea that autophagy may act as an executioner of cell death. However the notion of autophagy as a cell death mechanism has been controversial and remains mechanistically undefined. There is now growing evidence that in specific contexts autophagy can indeed facilitate cell death. The pro-death role of autophagy is however complicated due to the extensive cross-talk between different signalling pathways. This review summarises the examples of where autophagy acts as a means of cell death and discusses the association of autophagy with the different cell death pathways.
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141
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Maycotte P, Thorburn A. Targeting autophagy in breast cancer. World J Clin Oncol 2014; 5:224-240. [PMID: 25114840 PMCID: PMC4127596 DOI: 10.5306/wjco.v5.i3.224] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 04/02/2014] [Accepted: 05/29/2014] [Indexed: 02/06/2023] Open
Abstract
Macroautophagy (referred to as autophagy here) is an intracellular degradation pathway enhanced in response to a variety of stresses and in response to nutrient deprivation. This process provides the cell with nutrients and energy by degrading aggregated and damaged proteins as well as compromised organelles. Since autophagy has been linked to diverse diseases including cancer, it has recently become a very interesting target in breast cancer treatment. Indeed, current clinical trials are trying to use chloroquine or hydroxychloroquine, alone or in combination with other drugs to inhibit autophagy during breast cancer therapy since chemotherapy and radiation, regimens that are used to treat breast cancer, are known to induce autophagy in cancer cells. Importantly, in breast cancer, autophagy has been involved in the development of resistance to chemotherapy and to anti-estrogens. Moreover, a close relationship has recently been described between autophagy and the HER2 receptor. Here, we discuss some of the recent findings relating autophagy and cancer with a particular focus on breast cancer therapy.
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142
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Abstract
The core aspect of the senescent phenotype is a stable state of cell cycle arrest. However, this is a disguise that conceals a highly active metabolic cell state with diverse functionality. Both the cell-autonomous and the non-cell-autonomous activities of senescent cells create spatiotemporally dynamic and context-dependent tissue reactions. For example, the senescence-associated secretory phenotype (SASP) provokes not only tumour-suppressive but also tumour-promoting responses. Senescence is now increasingly considered to be an integrated and widespread component that is potentially important for tumour development, tumour suppression and the response to therapy.
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Affiliation(s)
- Pedro A Pérez-Mancera
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, CB2 0RE, UK
| | - Andrew R J Young
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, CB2 0RE, UK
| | - Masashi Narita
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, CB2 0RE, UK
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143
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Liu J, Zheng L, Ma L, Wang B, Zhao Y, Wu N, Liu G, Lin X. Oleanolic acid inhibits proliferation and invasiveness of Kras-transformed cells via autophagy. J Nutr Biochem 2014; 25:1154-1160. [PMID: 25172632 DOI: 10.1016/j.jnutbio.2014.06.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 05/06/2014] [Accepted: 06/30/2014] [Indexed: 01/11/2023]
Abstract
Oleanolic acid (OA) has been widely studied because of its pleiotropic therapeutic and preventive effect on various diseases. However, the mechanisms of OA's action are still not clear yet, especially its suppressing effect on transformed cells. In this work, we found that OA induced autophagy in normal tissue-derived cells without cytotoxicity. OA-induced autophagy was shown to decrease the proliferation of KRAS-transformed normal cells and to impair their invasion and anchorage-independent growth. Interrupting autophagy rescued OA's effect on the transformed cells. Mouse model experiments also demonstrated that OA suppressed the growth of KRAS-transformed breast epithelial cell MCF10A-derived tumor xenograft by inducing autophagy. Finally, we identified that OA induced autophagy in normal cells by inhibiting the activation of Akt/mTOR/S6K signaling. In conclusions, we found that OA treatment permitted normal cells to undergo autophagy. The induced autophagy was required for OA to prevent or delay the growth of transformed normal cells.
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Affiliation(s)
- Jia Liu
- College of Medicine, Qingdao University, Qingdao 266021, China; Institutes of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Lanhong Zheng
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
| | - Leina Ma
- Department of Molecular Biology, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Bin Wang
- Department of Gastroenterology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, China
| | - Youguang Zhao
- Department of Urology, General Hospital of Chengdu Military Area Command of Chinese PLA, Chengdu 610083, China
| | - Ning Wu
- Institutes of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Ge Liu
- Institutes of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Xiukun Lin
- Institutes of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Capital Med. University, Dept. of Pharmacology, Beijing 100069, China.
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144
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Manic G, Obrist F, Kroemer G, Vitale I, Galluzzi L. Chloroquine and hydroxychloroquine for cancer therapy. Mol Cell Oncol 2014; 1:e29911. [PMID: 27308318 PMCID: PMC4905171 DOI: 10.4161/mco.29911] [Citation(s) in RCA: 138] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 06/16/2014] [Indexed: 02/06/2023]
Abstract
Macroautophagy (herein referred to as autophagy) is a highly conserved mechanism for the lysosomal degradation of cytoplasmic components. Autophagy is critical for the maintenance of intracellular homeostasis, both in baseline conditions and in the context of adaptive responses to stress. In line with this notion, defects in the autophagic machinery have been etiologically associated with various human disorders including infectious, inflammatory and neoplastic conditions. Once tumors are established, however, autophagy sustains the survival of malignant cells, hence representing an appealing target for the design of novel anticancer regimens. Accordingly, inhibitors of autophagy including chloroquine and hydroxychloroquine have been shown to mediate substantial antineoplastic effects in preclinical models, especially when combined with chemo- or radiotherapeutic interventions. The pharmacological profile of chloroquine and hydroxychloroquine, however, appear to involve mechanisms other than autophagy inhibition. Here, we discuss the dual role of autophagy in oncogenesis and tumor progression, and summarize the results or design of clinical studies recently completed or initiated to evaluate the therapeutic activity of chloroquine derivatives in cancer patients.
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Affiliation(s)
| | - Florine Obrist
- Université Paris-Sud/Paris XI; Le Kremlin-Bicêtre, France; INSERM, UMRS1138; Villejuif, France; Equipe 11 labelisée par la Ligue Nationale contre le Cancer; Centre de Recherche des Cordeliers; Paris, France
| | - Guido Kroemer
- INSERM, UMRS1138; Villejuif, France; Equipe 11 labelisée par la Ligue Nationale contre le Cancer; Centre de Recherche des Cordeliers; Paris, France; Metabolomics and Cell Biology Platforms; Gustave Roussy Cancer Campus; Villejuif, France; Pôle de Biologie, Hôpital Européen Georges Pompidou, AP-HP; Paris, France
| | - Ilio Vitale
- Regina Elena National Cancer Institute; Rome, Italy
| | - Lorenzo Galluzzi
- Regina Elena National Cancer Institute; Rome, Italy; Equipe 11 labelisée par la Ligue Nationale contre le Cancer; Centre de Recherche des Cordeliers; Paris, France; Université Paris Descartes/Paris V; Sorbonne Paris Cité; Paris, France
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145
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Hönscheid P, Datta K, Muders MH. Autophagy: detection, regulation and its role in cancer and therapy response. Int J Radiat Biol 2014; 90:628-35. [PMID: 24678799 DOI: 10.3109/09553002.2014.907932] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
PURPOSE Macroautophagy is a catabolic pathway that degrades cellular components through the lysosomal machinery. Cytoplasmic components are sequestered in double-membrane autophagosomes. They fuse with lysosomes where their cargo is delivered for degradation and recycling. Autophagy acts as a survival mechanism under stress by producing energy and as an intracellular quality management system by clearing damaged organelles like mitochondria and proteins. In this review, the regulation and the role of autophagy in cancer and therapy response are discussed. Furthermore, we will summarize methods for detecting autophagy in vitro and in vivo. CONCLUSION During the early and late stages of cancer development, the role of autophagy differs. In the very early stages of carcinogenesis, autophagy has an important function by reducing cancer initiating genetic instability and aberrant protein aggregates as well as promoting anti-cancer immune response. In established malignant tumors autophagy confers resistance against metabolic stress caused by nutrient deprivation and the rapid proliferation of carcinoma cells. This function of autophagy is also important for radiation and chemotherapy resistance in cancer. Our laboratory has found that Neuropilin-2-induced autophagy is a potent mediator of therapy resistance in different cancer types. Autophagy not only promotes the survival of tumor cells, but also leads to autophagic cell death. During dysfunctional apoptosis this form of cell death mainly sensitizes cancer cells for therapy such as ionizing radiation. Therefore, the functions of autophagy during cancer progression and therapy are two-sided and further research is needed to understand these in more detail.
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Affiliation(s)
- Pia Hönscheid
- Institute of Pathology, University Hospital 'Carl Gustav Carus' Dresden , TU Dresden , Germany
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146
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Liu PF, Leung CM, Chang YH, Cheng JS, Chen JJ, Weng CJ, Tsai KW, Hsu CJ, Liu YC, Hsu PC, Pan HW, Shu CW. ATG4B promotes colorectal cancer growth independent of autophagic flux. Autophagy 2014; 10:1454-65. [PMID: 24991826 DOI: 10.4161/auto.29556] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Autophagy is reported to suppress tumor proliferation, whereas deficiency of autophagy is associated with tumorigenesis. ATG4B is a deubiquitin-like protease that plays dual roles in the core machinery of autophagy; however, little is known about the role of ATG4B on autophagy and proliferation in tumor cells. In this study, we found that ATG4B knockdown induced autophagic flux and reduced CCND1 expression to inhibit G 1/S phase transition of cell cycle in colorectal cancer cell lines, indicating functional dominance of ATG4B on autophagy inhibition and tumor proliferation in cancer cells. Interestingly, based on the genetic and pharmacological ablation of autophagy, the growth arrest induced by silencing ATG4B was independent of autophagic flux. Moreover, dephosphorylation of MTOR was involved in reduced CCND1 expression and G 1/S phase transition in both cells and xenograft tumors with depletion of ATG4B. Furthermore, ATG4B expression was significantly increased in tumor cells of colorectal cancer patients compared with adjacent normal cells. The elevated expression of ATG4B was highly correlated with CCND1 expression, consistently supporting the notion that ATG4B might contribute to MTOR-CCND1 signaling for G 1/S phase transition in colorectal cancer cells. Thus, we report that ATG4B independently plays a role as a positive regulator on tumor proliferation and a negative regulator on autophagy in colorectal cancer cells. These results suggest that ATG4B is a potential biomarker and drug target for cancer therapy.
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Affiliation(s)
- Pei-Feng Liu
- Department of Medical Education and Research; Kaohsiung Veterans General Hospital; Kaohsiung, Taiwan; Department of Biotechnology; Fooyin University; Kaohsiung, Taiwan
| | - Chung-Man Leung
- Department of Radiation Oncology; Kaohsiung Veterans General Hospital; Kaohsiung, Taiwan; Department of Safety, Health and Environmental Engineering; National Kaohsiung First University of Science and Technology; Kaohsiung, Taiwan
| | - Yu-Hsiang Chang
- Department of Pediatrics; Kaohsiung Veterans General Hospital; Kaohsiung, Taiwan; School of Medicine; National Yang-Ming University; Taipei, Taiwan; Department of Nursing; Tajen University; Pingtung, Taiwan
| | - Jin-Shiung Cheng
- Department of Internal Medicine; Kaohsiung Veterans General Hospital; Kaohsiung, Taiwan
| | - Jih-Jung Chen
- Department of Pharmacy and Graduate Institute of Pharmaceutical Technology; Tajen University; Pingtung, Taiwan
| | - Chung-Jeu Weng
- Department of Obstetrics Gynecology; Zuoying Branch of Kaohsiung Armed Forces General Hospital; Kaohsiung, Taiwan
| | - Kuo-Wang Tsai
- Department of Medical Education and Research; Kaohsiung Veterans General Hospital; Kaohsiung, Taiwan
| | - Chien-Jen Hsu
- Department of Medical Education and Research; Kaohsiung Veterans General Hospital; Kaohsiung, Taiwan
| | - Yen-Chen Liu
- Department of Medical Education and Research; Kaohsiung Veterans General Hospital; Kaohsiung, Taiwan
| | - Ping-Chi Hsu
- Department of Safety, Health and Environmental Engineering; National Kaohsiung First University of Science and Technology; Kaohsiung, Taiwan
| | - Hung-Wei Pan
- Department of Medical Education and Research; Kaohsiung Veterans General Hospital; Kaohsiung, Taiwan
| | - Chih-Wen Shu
- Department of Medical Education and Research; Kaohsiung Veterans General Hospital; Kaohsiung, Taiwan
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147
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Feng L, Ma Y, Sun J, Shen Q, Liu L, Lu H, Wang F, Yue Y, Li J, Zhang S, Lin X, Chu J, Han W, Wang X, Jin H. YY1-MIR372-SQSTM1 regulatory axis in autophagy. Autophagy 2014; 10:1442-53. [PMID: 24991827 DOI: 10.4161/auto.29486] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Autophagy is a self-proteolytic process that degrades intracellular material to enable cellular survival under unfavorable conditions. However, how autophagy is activated in human carcinogenesis remains largely unknown. Herein we report an epigenetic regulation of autophagy in human cancer cells. YY1 (YY1 transcription factor) is a well-known epigenetic regulator and is upregulated in many cancers. We found that YY1 knockdown inhibited cell viability and autophagy flux through downregulating SQSTM1 (sequestosome 1). YY1 regulated SQSTM1 expression through the epigenetic modulation of the transcription of MIR372 (microRNA 372) which was found to target SQSTM1 directly. During nutrient starvation, YY1 was stimulated to promote SQSTM1 expression and subsequent autophagy activation by suppressing MIR372 expression. Similar to YY1 depletion, MIR372 overexpression blocked autophagy activation and inhibited in vivo tumor growth. SQSTM1 upregulation and competent autophagy flux thus contributed to the oncogenic function of YY1. YY1-promoted SQSTM1 upregulation might be a useful histological marker for cancer detection and a potential target for drug development.
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Affiliation(s)
- Lifeng Feng
- Laboratory of Cancer Biology; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang China
| | - Yanning Ma
- Laboratory of Cancer Biology; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang China
| | - Jie Sun
- Laboratory of Cancer Biology; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang China
| | - Qi Shen
- Department of Medical Oncology; Institute of Clinical Science; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang Province China
| | - Leiming Liu
- Laboratory of Cancer Biology; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang China
| | - Haiqi Lu
- Laboratory of Cancer Biology; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang China
| | - Faliang Wang
- Laboratory of Cancer Biology; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang China
| | - Yongfang Yue
- Laboratory of Cancer Biology; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang China
| | - Jiaqiu Li
- Department of Medical Oncology; Institute of Clinical Science; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang Province China
| | - Shenjie Zhang
- Laboratory of Cancer Biology; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang China
| | - Xiaoying Lin
- Laboratory of Cancer Biology; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang China
| | - Jue Chu
- Laboratory of Cancer Biology; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang China
| | - Weidong Han
- Department of Medical Oncology; Institute of Clinical Science; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang Province China
| | - Xian Wang
- Department of Medical Oncology; Institute of Clinical Science; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang Province China
| | - Hongchuan Jin
- Laboratory of Cancer Biology; Sir Runrun Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou, Zhejiang China
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148
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Deschênes-Simard X, Lessard F, Gaumont-Leclerc MF, Bardeesy N, Ferbeyre G. Cellular senescence and protein degradation: breaking down cancer. Cell Cycle 2014; 13:1840-58. [PMID: 24866342 DOI: 10.4161/cc.29335] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Autophagy and the ubiquitin-proteasome pathway (UPP) are the major protein degradation systems in eukaryotic cells. Whereas the former mediate a bulk nonspecific degradation, the UPP allows a rapid degradation of specific proteins. Both systems have been shown to play a role in tumorigenesis, and the interest in developing therapeutic agents inhibiting protein degradation is steadily growing. However, emerging data point to a critical role for autophagy in cellular senescence, an established tumor suppressor mechanism. Recently, a selective protein degradation process mediated by the UPP was also shown to contribute to the senescence phenotype. This process is tightly regulated by E3 ubiquitin ligases, deubiquitinases, and several post-translational modifications of target proteins. Illustrating the complexity of UPP, more than 600 human genes have been shown to encode E3 ubiquitin ligases, a number which exceeds that of the protein kinases. Nevertheless, our knowledge of proteasome-dependent protein degradation as a regulated process in cellular contexts such as cancer and senescence remains very limited. Here we discuss the implications of protein degradation in senescence and attempt to relate this function to the protein degradation pattern observed in cancer cells.
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Affiliation(s)
- Xavier Deschênes-Simard
- Department of Biochemistry and Molecular Medicine; Université de Montréal; Montréal, Québec, Canada
| | - Frédéric Lessard
- Department of Biochemistry and Molecular Medicine; Université de Montréal; Montréal, Québec, Canada
| | | | - Nabeel Bardeesy
- Massachusetts General Hospital Cancer Center; Harvard Medical School; Boston, MA USA
| | - Gerardo Ferbeyre
- Department of Biochemistry and Molecular Medicine; Université de Montréal; Montréal, Québec, Canada
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149
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The core autophagy protein ATG4B is a potential biomarker and therapeutic target in CML stem/progenitor cells. Blood 2014; 123:3622-34. [PMID: 24755409 DOI: 10.1182/blood-2013-07-516807] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Previous studies demonstrated that imatinib mesylate (IM) induces autophagy in chronic myeloid leukemia (CML) and that this process is critical to cell survival upon therapy. However, it is not known if the autophagic process differs at basal levels between CML patients and healthy individuals and if pretreatment CML cells harbor unique autophagy characteristics that could predict patients' clinical outcomes. We now demonstrate that several key autophagy genes are differentially expressed in CD34(+) hematopoietic stem/progenitor cells, with the highest transcript levels detected for ATG4B, and that the transcript and protein expression levels of ATG4 family members, ATG5 and BECLIN-1 are significantly increased in CD34(+) cells from chronic-phase CML patients (P < .05). Importantly, ATG4B is differentially expressed in pretreatment CML stem/progenitor cells from subsequent IM responders vs IM nonresponders (P < .05). Knockdown of ATG4B suppresses autophagy, impairs the survival of CML stem/progenitor cells and sensitizes them to IM treatment. Moreover, deregulated expression of ATG4B in CD34(+) CML cells inversely correlates with transcript levels of miR-34a, and ATG4B is shown to be a direct target of miR-34a. This study identifies ATG4B as a potential biomarker for predicting therapeutic response in treatment-naïve CML stem/progenitor cells and uncovers ATG4B as a possible drug target in these cells.
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150
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Choi S, Shin H, Song H, Lim HJ. Suppression of autophagic activation in the mouse uterus by estrogen and progesterone. J Endocrinol 2014; 221:39-50. [PMID: 24443716 DOI: 10.1530/joe-13-0449] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Autophagy is a major cellular catabolic pathway tightly associated with cell survival. The involvement of autophagy in the prolonged survival of blastocysts in the uterus is well established, and it was assumed that ovarian steroid hormones - progesterone (P4) and estrogens - have important roles in the regulation of autophagy. However, information is scarce regarding whether these hormones regulate autophagy in certain hormone-responsive cellular systems. In this study, we investigated the effects of estrogen and P4 on autophagic response in the uteri of pregnant mice and in ovariectomized (OVX) mice treated with hormones. During pregnancy, autophagic response is high on days 1 and 2 when the uterus shows an inflammatory response to mating, but it subsides around the time of implantation. Dexamethasone treatment to day 1 pregnant mice reduced autophagy in the uterus. In OVX mouse uteri, estrogen or P4 reduces autophagic response within 6 h. Glycogen content in OVX uteri was increased by 3-methyladenine treatment, suggesting that autophagy is involved in glycogen breakdown in the hormone-deprived uterus. The classical nuclear receptor antagonists, ICI 182 780 or mifepristone, lead to the recovery of the autophagic response in OVX uteri. The suppression of autophagy by 17β-estradiol is inversely correlated with the accumulation of phospho-mouse target of rapamycin, and rapamycin treatment is moderately effective in the upregulation of autophagic response in OVX mouse uteri. Collectively, this study establishes that the uterine autophagy is induced in hormone-derived environment and is suppressed by hormone treatment. Uterine autophagy may have multiple functions as a responsive mechanism to acute inflammation and as an energy provider by breaking down glycogen under hormone deprivation.
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Affiliation(s)
- Soyoung Choi
- Department of Biomedical Science and Technology, Institute of Biomedical Science and Technology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 143-701, Korea Department of Biomedical Science, College of Life Science, CHA University, Seoul 135-081, Korea
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