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Ravichandran R, PriyaDharshini LC, Sakthivel KM, Rasmi RR. Role and regulation of autophagy in cancer. Biochim Biophys Acta Mol Basis Dis 2022; 1868:166400. [PMID: 35341960 DOI: 10.1016/j.bbadis.2022.166400] [Citation(s) in RCA: 49] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 03/17/2022] [Accepted: 03/18/2022] [Indexed: 02/07/2023]
Abstract
Autophagy is an intracellular self-degradative mechanism which responds to cellular conditions like stress or starvation and plays a key role in regulating cell metabolism, energy homeostasis, starvation adaptation, development and cell death. Numerous studies have stipulated the participation of autophagy in cancer, but the role of autophagy either as tumor suppressor or tumor promoter is not clearly understood. However, mechanisms by which autophagy promotes cancer involves a diverse range of modifications of autophagy associated proteins such as ATGs, Beclin-1, mTOR, p53, KRAS etc. and autophagy pathways like mTOR, PI3K, MAPK, EGFR, HIF and NFκB. Furthermore, several researches have highlighted a context-dependent, cell type and stage-dependent regulation of autophagy in cancer. Alongside this, the interaction between tumor cells and their microenvironment including hypoxia has a great potential in modulating autophagy response in favour to substantiate cancer cell metabolism, self-proliferation and metastasis. In this review article, we highlight the mechanism of autophagy and their contribution to cancer cell proliferation and development. In addition, we discuss about tumor microenvironment interaction and their consequence on selective autophagy pathways and the involvement of autophagy in various tumor types and their therapeutic interventions concentrated on exploiting autophagy as a potential target to improve cancer therapy.
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Affiliation(s)
- Rakesh Ravichandran
- Department of Biotechnology, PSG College of Arts and Science, Civil Aerodrome Post, Coimbatore 641 014, Tamil Nadu, India
| | | | - Kunnathur Murugesan Sakthivel
- Department of Biochemistry, PSG College of Arts and Science, Civil Aerodrome Post, Coimbatore 641 014, Tamil Nadu, India
| | - Rajan Radha Rasmi
- Department of Biotechnology, PSG College of Arts and Science, Civil Aerodrome Post, Coimbatore 641 014, Tamil Nadu, India.
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2
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Niklaus NJ, Tokarchuk I, Zbinden M, Schläfli AM, Maycotte P, Tschan MP. The Multifaceted Functions of Autophagy in Breast Cancer Development and Treatment. Cells 2021; 10:cells10061447. [PMID: 34207792 PMCID: PMC8229352 DOI: 10.3390/cells10061447] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 06/04/2021] [Accepted: 06/04/2021] [Indexed: 12/12/2022] Open
Abstract
Macroautophagy (herein referred to as autophagy) is a complex catabolic process characterized by the formation of double-membrane vesicles called autophagosomes. During this process, autophagosomes engulf and deliver their intracellular content to lysosomes, where they are degraded by hydrolytic enzymes. Thereby, autophagy provides energy and building blocks to maintain cellular homeostasis and represents a dynamic recycling mechanism. Importantly, the clearance of damaged organelles and aggregated molecules by autophagy in normal cells contributes to cancer prevention. Therefore, the dysfunction of autophagy has a major impact on the cell fate and can contribute to tumorigenesis. Breast cancer is the most common cancer in women and has the highest mortality rate among all cancers in women worldwide. Breast cancer patients often have a good short-term prognosis, but long-term survivors often experience aggressive recurrence. This phenomenon might be explained by the high heterogeneity of breast cancer tumors rendering mammary tumors difficult to target. This review focuses on the mechanisms of autophagy during breast carcinogenesis and sheds light on the role of autophagy in the traits of aggressive breast cancer cells such as migration, invasion, and therapeutic resistance.
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Affiliation(s)
- Nicolas J. Niklaus
- Institute of Pathology, University of Bern, CH-3008 Bern, Switzerland; (N.J.N.); (I.T.); (M.Z.); (A.M.S.)
- Graduate School for Cellular and Biomedical Sciences, University of Bern, CH-3012 Bern, Switzerland
| | - Igor Tokarchuk
- Institute of Pathology, University of Bern, CH-3008 Bern, Switzerland; (N.J.N.); (I.T.); (M.Z.); (A.M.S.)
- Graduate School for Cellular and Biomedical Sciences, University of Bern, CH-3012 Bern, Switzerland
| | - Mara Zbinden
- Institute of Pathology, University of Bern, CH-3008 Bern, Switzerland; (N.J.N.); (I.T.); (M.Z.); (A.M.S.)
| | - Anna M. Schläfli
- Institute of Pathology, University of Bern, CH-3008 Bern, Switzerland; (N.J.N.); (I.T.); (M.Z.); (A.M.S.)
| | - Paola Maycotte
- Centro de Investigación Biomédica de Oriente (CIBIOR), Instituto Mexicano del Seguro Social (IMSS), Puebla 74360, Mexico;
| | - Mario P. Tschan
- Institute of Pathology, University of Bern, CH-3008 Bern, Switzerland; (N.J.N.); (I.T.); (M.Z.); (A.M.S.)
- Graduate School for Cellular and Biomedical Sciences, University of Bern, CH-3012 Bern, Switzerland
- Correspondence: ; Tel.: +41-31-632-87-80
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3
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Maiti A, Hait NC. Autophagy-mediated tumor cell survival and progression of breast cancer metastasis to the brain. J Cancer 2021; 12:954-964. [PMID: 33442395 PMCID: PMC7797661 DOI: 10.7150/jca.50137] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 10/07/2020] [Indexed: 02/07/2023] Open
Abstract
Brain metastases represent a substantial amount of morbidity and mortality in breast cancer (BC). Metastatic breast tumor cells committed to brain metastases are unique because they escape immune surveillance, can penetrate the blood-brain barrier, and also adapt to the brain tissue microenvironment (TME) for colonization and outgrowth. In addition, dynamic intracellular interactions between metastatic cancer cells and neighboring astrocytes in the brain are thought to play essential roles in brain tumor progression. A better understanding of the above mechanisms will lead to developing more effective therapies for brain metastases. Growing literature suggests autophagy, a conserved lysosomal degradation pathway involved in cellular homeostasis under stressful conditions, plays essential roles in breast tumor metastatic transformation and brain metastases. Cancer cells must adapt under various microenvironmental stresses, such as hypoxia, and nutrient (glucose) deprivation, in order to survive and progress. Clinical studies reveal that tumoral expression of autophagy-related proteins is higher in brain metastasis compared to primary breast tumors. In this review, we outline the molecular mechanisms underlying autophagy-mediated BC cell survival and metastasis to the brain.
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Affiliation(s)
- Aparna Maiti
- Division of Breast Surgery and Department of Surgical Oncology, Department of Molecular & Cellular Biology, Roswell Park Comprehensive Cancer Center, Buffalo, New York, 14263, USA
| | - Nitai C. Hait
- Division of Breast Surgery and Department of Surgical Oncology, Department of Molecular & Cellular Biology, Roswell Park Comprehensive Cancer Center, Buffalo, New York, 14263, USA
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4
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Vega-Rubín-de-Celis S, Kinch L, Peña-Llopis S. Regulation of Beclin 1-Mediated Autophagy by Oncogenic Tyrosine Kinases. Int J Mol Sci 2020; 21:ijms21239210. [PMID: 33287140 PMCID: PMC7729755 DOI: 10.3390/ijms21239210] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/28/2020] [Accepted: 12/01/2020] [Indexed: 12/12/2022] Open
Abstract
Beclin 1 is a major regulator of autophagy, and it is a core component of the class III PI3K complexes. Beclin 1 is a highly conserved protein and its function is regulated in a number of ways, including post-translational modifications. Several studies indicate that receptor and non-receptor tyrosine kinases regulate autophagy activity in cancer, and some suggest the importance of Beclin 1 tyrosine phosphorylation in this process. Here we summarize the current knowledge of the mechanism whereby some oncogenic tyrosine kinases regulate autophagy through Beclin 1.
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Affiliation(s)
- Silvia Vega-Rubín-de-Celis
- Institute for Cell Biology (Cancer Research), University Hospital Essen, 45147 Essen, Germany
- Correspondence: or
| | - Lisa Kinch
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA;
| | - Samuel Peña-Llopis
- Translational Genomics in Solid Tumors, German Cancer Consortium (DKTK) and German Cancer Research Center, University Hospital Essen, 45147 Essen, Germany;
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5
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Tyutyunyk-Massey L, Gewirtz DA. Roles of autophagy in breast cancer treatment: Target, bystander or benefactor. Semin Cancer Biol 2020; 66:155-162. [DOI: 10.1016/j.semcancer.2019.11.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 11/21/2019] [Accepted: 11/29/2019] [Indexed: 12/11/2022]
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Cocco S, Leone A, Piezzo M, Caputo R, Di Lauro V, Di Rella F, Fusco G, Capozzi M, Gioia GD, Budillon A, De Laurentiis M. Targeting Autophagy in Breast Cancer. Int J Mol Sci 2020; 21:ijms21217836. [PMID: 33105796 PMCID: PMC7660056 DOI: 10.3390/ijms21217836] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/19/2020] [Accepted: 10/21/2020] [Indexed: 02/07/2023] Open
Abstract
Breast cancer is a heterogeneous disease consisting of different biological subtypes, with differences in terms of incidence, response to diverse treatments, risk of disease progression, and sites of metastases. In the last years, several molecular targets have emerged and new drugs, targeting PI3K/Akt/mTOR and cyclinD/CDK/pRb pathways and tumor microenvironment have been integrated into clinical practice. However, it is clear now that breast cancer is able to develop resistance to these drugs and the identification of the underlying molecular mechanisms is paramount to drive further drug development. Autophagy is a highly conserved homeostatic process that can be activated in response to antineoplastic agents as a cytoprotective mechanism. Inhibition of autophagy could enhance tumor cell death by diverse anti-cancer therapies, representing an attractive approach to control mechanisms of drug resistance. In this manuscript, we present a review of autophagy focusing on its interplay with targeted drugs used for breast cancer treatment.
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Affiliation(s)
- Stefania Cocco
- Breast Unit, Istituto Nazionale Tumori IRCCS “Fondazione G. Pascale”, Via Mariano Semmola 53, 80131 Napoli, Italy; (M.P.); (R.C.); (V.D.L.); (F.D.R.); (G.F.); (M.C.); (G.d.G.)
- Correspondence: (S.C.); (M.D.L.)
| | - Alessandra Leone
- Experimental Pharmacology Unit, Istituto Nazionale Tumori IRCCS “Fondazione G. Pascale”, Via Mariano Semmola 53, 80131 Napoli, Italy; (A.L.); (A.B.)
| | - Michela Piezzo
- Breast Unit, Istituto Nazionale Tumori IRCCS “Fondazione G. Pascale”, Via Mariano Semmola 53, 80131 Napoli, Italy; (M.P.); (R.C.); (V.D.L.); (F.D.R.); (G.F.); (M.C.); (G.d.G.)
| | - Roberta Caputo
- Breast Unit, Istituto Nazionale Tumori IRCCS “Fondazione G. Pascale”, Via Mariano Semmola 53, 80131 Napoli, Italy; (M.P.); (R.C.); (V.D.L.); (F.D.R.); (G.F.); (M.C.); (G.d.G.)
| | - Vincenzo Di Lauro
- Breast Unit, Istituto Nazionale Tumori IRCCS “Fondazione G. Pascale”, Via Mariano Semmola 53, 80131 Napoli, Italy; (M.P.); (R.C.); (V.D.L.); (F.D.R.); (G.F.); (M.C.); (G.d.G.)
| | - Francesca Di Rella
- Breast Unit, Istituto Nazionale Tumori IRCCS “Fondazione G. Pascale”, Via Mariano Semmola 53, 80131 Napoli, Italy; (M.P.); (R.C.); (V.D.L.); (F.D.R.); (G.F.); (M.C.); (G.d.G.)
| | - Giuseppina Fusco
- Breast Unit, Istituto Nazionale Tumori IRCCS “Fondazione G. Pascale”, Via Mariano Semmola 53, 80131 Napoli, Italy; (M.P.); (R.C.); (V.D.L.); (F.D.R.); (G.F.); (M.C.); (G.d.G.)
| | - Monica Capozzi
- Breast Unit, Istituto Nazionale Tumori IRCCS “Fondazione G. Pascale”, Via Mariano Semmola 53, 80131 Napoli, Italy; (M.P.); (R.C.); (V.D.L.); (F.D.R.); (G.F.); (M.C.); (G.d.G.)
| | - Germira di Gioia
- Breast Unit, Istituto Nazionale Tumori IRCCS “Fondazione G. Pascale”, Via Mariano Semmola 53, 80131 Napoli, Italy; (M.P.); (R.C.); (V.D.L.); (F.D.R.); (G.F.); (M.C.); (G.d.G.)
| | - Alfredo Budillon
- Experimental Pharmacology Unit, Istituto Nazionale Tumori IRCCS “Fondazione G. Pascale”, Via Mariano Semmola 53, 80131 Napoli, Italy; (A.L.); (A.B.)
| | - Michelino De Laurentiis
- Breast Unit, Istituto Nazionale Tumori IRCCS “Fondazione G. Pascale”, Via Mariano Semmola 53, 80131 Napoli, Italy; (M.P.); (R.C.); (V.D.L.); (F.D.R.); (G.F.); (M.C.); (G.d.G.)
- Correspondence: (S.C.); (M.D.L.)
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7
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Tumors Responsive to Autophagy-Inhibition: Identification and Biomarkers. Cancers (Basel) 2020; 12:cancers12092463. [PMID: 32878084 PMCID: PMC7563256 DOI: 10.3390/cancers12092463] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/25/2020] [Accepted: 08/27/2020] [Indexed: 02/06/2023] Open
Abstract
Simple Summary Although the principle of personalized medicine has been the focus of attention, many cancer therapies are still based on a one-size-fits-all approach. The same holds true for targeting cancer cell survival mechanism that allows cancer cells to recycle their constituents (autophagy). In the past several indicators of elevated dependence of cancer cells on autophagy have been described. Addition of autophagy-inhibiting agents could be beneficial in treatment of these tumors. The biomarkers and mechanisms that lead to elevated dependence on autophagy are reviewed in the current manuscript. Abstract Recent advances in cancer treatment modalities reveal the limitations of the prevalent “one-size-fits-all” therapies and emphasize the necessity to develop personalized approaches. In this perspective, identification of predictive biomarkers and intrinsic vulnerabilities are an important advancement for further therapeutic strategies. Autophagy is an important lysosomal degradation and recycling pathway that provides energy and macromolecular precursors to maintain cellular homeostasis. Although all cells require autophagy, several genetic and/or cellular changes elevate the dependence of cancer cells on autophagy for their survival and indicates that autophagy inhibition in these tumors could provide a favorable addition to current therapies. In this context, we review the current literature on tumor (sub)types with elevated dependence on autophagy for their survival and highlight an exploitable vulnerability. We provide an inventory of microenvironmental factors, genetic alterations and therapies that may be exploited with autophagy-targeted approaches to improve efficacy of conventional anti-tumor therapies.
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Zhang Y, Whaley-Connell AT, Sowers JR, Ren J. Autophagy as an emerging target in cardiorenal metabolic disease: From pathophysiology to management. Pharmacol Ther 2018; 191:1-22. [PMID: 29909238 PMCID: PMC6195437 DOI: 10.1016/j.pharmthera.2018.06.004] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 06/05/2018] [Indexed: 12/16/2022]
Abstract
Although advances in medical technology and health care have improved the early diagnosis and management for cardiorenal metabolic disorders, the prevalence of obesity, insulin resistance, diabetes, hypertension, dyslipidemia, and kidney disease remains high. Findings from numerous population-based studies, clinical trials, and experimental evidence have consolidated a number of theories for the pathogenesis of cardiorenal metabolic anomalies including resistance to the metabolic action of insulin, abnormal glucose and lipid metabolism, oxidative and nitrosative stress, endoplasmic reticulum (ER) stress, apoptosis, mitochondrial damage, and inflammation. Accumulating evidence has recently suggested a pivotal role for proteotoxicity, the unfavorable effects of poor protein quality control, in the pathophysiology of metabolic dysregulation and related cardiovascular complications. The ubiquitin-proteasome system (UPS) and autophagy-lysosomal pathways, two major although distinct cellular clearance machineries, govern protein quality control by degradation and clearance of long-lived or damaged proteins and organelles. Ample evidence has depicted an important role for protein quality control, particularly autophagy, in the maintenance of metabolic homeostasis. To this end, autophagy offers promising targets for novel strategies to prevent and treat cardiorenal metabolic diseases. Targeting autophagy using pharmacological or natural agents exhibits exciting new strategies for the growing problem of cardiorenal metabolic disorders.
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Affiliation(s)
- Yingmei Zhang
- Shanghai Institute of Cardiovascular Diseases, Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Center for Cardiovascular Research and Alternative Medicine, University of Wyoming College of Health Sciences, Laramie, WY 82071, USA.
| | - Adam T Whaley-Connell
- Research Service, Harry S Truman Memorial Veterans' Hospital, University of Missouri-Columbia School of Medicine, Columbia, MO, USA; Diabetes and Cardiovascular Center, Department of Medicine, University of Missouri-Columbia School of Medicine, Columbia, MO, USA
| | - James R Sowers
- Research Service, Harry S Truman Memorial Veterans' Hospital, University of Missouri-Columbia School of Medicine, Columbia, MO, USA; Diabetes and Cardiovascular Center, Department of Medicine, University of Missouri-Columbia School of Medicine, Columbia, MO, USA
| | - Jun Ren
- Shanghai Institute of Cardiovascular Diseases, Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Center for Cardiovascular Research and Alternative Medicine, University of Wyoming College of Health Sciences, Laramie, WY 82071, USA.
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9
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Abstract
Obesity poses a severe threat to human health, including the increased prevalence of hypertension, insulin resistance, diabetes mellitus, cancer, inflammation, sleep apnoea and other chronic diseases. Current therapies focus mainly on suppressing caloric intake, but the efficacy of this approach remains poor. A better understanding of the pathophysiology of obesity will be essential for the management of obesity and its complications. Knowledge gained over the past three decades regarding the aetiological mechanisms underpinning obesity has provided a framework that emphasizes energy imbalance and neurohormonal dysregulation, which are tightly regulated by autophagy. Accordingly, there is an emerging interest in the role of autophagy, a conserved homeostatic process for cellular quality control through the disposal and recycling of cellular components, in the maintenance of cellular homeostasis and organ function by selectively ridding cells of potentially toxic proteins, lipids and organelles. Indeed, defects in autophagy homeostasis are implicated in metabolic disorders, including obesity, insulin resistance, diabetes mellitus and atherosclerosis. In this Review, the alterations in autophagy that occur in response to nutrient stress, and how these changes alter the course of obesogenesis and obesity-related complications, are discussed. The potential of pharmacological modulation of autophagy for the management of obesity is also addressed.
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Affiliation(s)
- Yingmei Zhang
- Department of Cardiology, Fudan University Zhongshan Hospital, Shanghai, China.
- Center for Cardiovascular Research and Alternative Medicine, University of Wyoming College of Health Sciences, Laramie, WY, USA.
| | - James R Sowers
- Diabetes and Cardiovascular Research Center, University of Missouri-Columbia School of Medicine, Columbia, MO, USA
| | - Jun Ren
- Department of Cardiology, Fudan University Zhongshan Hospital, Shanghai, China.
- Center for Cardiovascular Research and Alternative Medicine, University of Wyoming College of Health Sciences, Laramie, WY, USA.
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10
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Abstract
Approximately 20% of breast cancers have amplification of a cancer-causing signaling molecule known as human epidermal growth factor receptor 2 (HER2). Decreased mRNA expression of the autophagy gene, beclin 1/BECN1, increases the risk of HER2-positive breast cancer. However, the role of Beclin 1-dependent autophagy in regulating HER2-mediated tumorigenesis is unknown. Here, we show that a mutation in Becn1 that increases basal autophagy prevents HER2-mediated tumorigenesis in mice and prevents HER2-mediated inhibition of autophagy in cultured cells. Furthermore, treatment with a cell-penetrating, autophagy-inducing peptide derived from Beclin 1 inhibits growth of HER2-positive human breast tumor xenografts in mice as efficiently as a clinically used agent that inhibits HER2 receptor tyrosine kinase activity. These findings demonstrate that genetic and pharmacological activation of autophagy inhibits HER2-mediated breast tumorigenesis. Allelic loss of the autophagy gene, beclin 1/BECN1, increases the risk of patients developing aggressive, including human epidermal growth factor receptor 2 (HER2)-positive, breast cancers; however, it is not known whether autophagy induction may be beneficial in preventing HER2-positive breast tumor growth. We explored the regulation of autophagy in breast cancer cells by HER2 in vitro and the effects of genetic and pharmacological strategies to increase autophagy on HER2-driven breast cancer growth in vivo. Our findings demonstrate that HER2 interacts with Beclin 1 in breast cancer cells and inhibits autophagy. Mice with increased basal autophagy due to a genetically engineered mutation in Becn1 are protected from HER2-driven mammary tumorigenesis, and HER2 fails to inhibit autophagy in primary cells derived from these mice. Moreover, treatment of mice with HER2-positive human breast cancer xenografts with the Tat-Beclin 1 autophagy-inducing peptide inhibits tumor growth as effectively as a clinically used HER2 tyrosine kinase inhibitor (TKI). This inhibition of tumor growth is associated with a robust induction of autophagy, a disruption of HER2/Beclin 1 binding, and a transcriptional signature in the tumors distinct from that observed with HER2 TKI treatment. Taken together, these findings indicate that the HER2-mediated inhibition of Beclin 1 and autophagy likely contributes to HER2-mediated tumorigenesis and that strategies to block HER2/Beclin 1 binding and/or increase autophagy may represent a new therapeutic approach for HER2-positive breast cancers.
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11
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Identification of breast cancer cell subtypes sensitive to ATG4B inhibition. Oncotarget 2018; 7:66970-66988. [PMID: 27556700 PMCID: PMC5341851 DOI: 10.18632/oncotarget.11408] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Accepted: 08/09/2016] [Indexed: 01/22/2023] Open
Abstract
Autophagy, a lysosome-mediated degradation and recycling process, functions in advanced malignancies to promote cancer cell survival and contribute to cancer progression and drug resistance. While various autophagy inhibition strategies are under investigation for cancer treatment, corresponding patient selection criteria for these autophagy inhibitors need to be developed. Due to its central roles in the autophagy process, the cysteine protease ATG4B is one of the autophagy proteins being pursued as a potential therapeutic target. In this study, we investigated the expression of ATG4B in breast cancer, a heterogeneous disease comprised of several molecular subtypes. We examined a panel of breast cancer cell lines, xenograft tumors, and breast cancer patient specimens for the protein expression of ATG4B, and found a positive association between HER2 and ATG4B protein expression. We showed that HER2-positive cells, but not HER2-negative breast cancer cells, require ATG4B to survive under stress. In HER2-positive cells, cytoprotective autophagy was dependent on ATG4B under both starvation and HER2 inhibition conditions. Combined knockdown of ATG4B and HER2 by siRNA resulted in a significant decrease in cell viability, and the combination of ATG4B knockdown with trastuzumab resulted in a greater reduction in cell viability compared to trastuzumab treatment alone, in both trastuzumab-sensitive and -resistant HER2 overexpressing breast cancer cells. Together these results demonstrate a novel association of ATG4B positive expression with HER2 positive breast cancers and indicate that this subtype is suitable for emerging ATG4B inhibition strategies.
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12
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Autophagy Modulation in Cancer: Current Knowledge on Action and Therapy. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2018; 2018:8023821. [PMID: 29643976 PMCID: PMC5831833 DOI: 10.1155/2018/8023821] [Citation(s) in RCA: 138] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 11/13/2017] [Accepted: 12/14/2017] [Indexed: 12/16/2022]
Abstract
In the last two decades, accumulating evidence pointed to the importance of autophagy in various human diseases. As an essential evolutionary catabolic process of cytoplasmatic component digestion, it is generally believed that modulating autophagic activity, through targeting specific regulatory actors in the core autophagy machinery, may impact disease processes. Both autophagy upregulation and downregulation have been found in cancers, suggesting its dual oncogenic and tumor suppressor properties during malignant transformation. Identification of the key autophagy targets is essential for the development of new therapeutic agents. Despite this great potential, no therapies are currently available that specifically focus on autophagy modulation. Although drugs like rapamycin, chloroquine, hydroxychloroquine, and others act as autophagy modulators, they were not originally developed for this purpose. Thus, autophagy may represent a new and promising pharmacologic target for future drug development and therapeutic applications in human diseases. Here, we summarize our current knowledge in regard to the interplay between autophagy and malignancy in the most significant tumor types: pancreatic, breast, hepatocellular, colorectal, and lung cancer, which have been studied in respect to autophagy manipulation as a promising therapeutic strategy. Finally, we present an overview of the most recent advances in therapeutic strategies involving autophagy modulators in cancer.
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Shi H, Zhang W, Zhi Q, Jiang M. Lapatinib resistance in HER2+ cancers: latest findings and new concepts on molecular mechanisms. Tumour Biol 2016; 37:10.1007/s13277-016-5467-2. [PMID: 27726101 DOI: 10.1007/s13277-016-5467-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 09/23/2016] [Indexed: 12/12/2022] Open
Abstract
In the era of new and mostly effective molecular targeted therapies, human epidermal growth factor receptor 2 positive (HER2+) cancers are still intractable diseases. Lapatinib, a dual epidermal growth factor receptor (EGFR) and HER2 tyrosine kinase inhibitor, has greatly improved breast cancer prognosis in recent years after the initial introduction of trastuzumab (Herceptin). However, clinical evidence indicates the existence of both primary unresponsiveness and secondary lapatinib resistance, which leads to the failure of this agent in HER2+ cancer patients. It remains a major clinical challenge to target the oncogenic pathways with drugs having low resistance. Multiple pathways are involved in the occurrence of lapatinib resistance, including the pathways of receptor tyrosine kinase, non-receptor tyrosine kinase, autophagy, apoptosis, microRNA, cancer stem cell, tumor metabolism, cell cycle, and heat shock protein. Moreover, understanding the relationship among these mechanisms may contribute to future tumor combination therapies. Therefore, it is of urgent necessity to elucidate the precise mechanisms of lapatinib resistance and improve the therapeutic use of this agent in clinic. The present review, in the hope of providing further scientific support for molecular targeted therapies in HER2+ cancers, discusses about the latest findings and new concepts on molecular mechanisms underlying lapatinib resistance.
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Affiliation(s)
- Huiping Shi
- Department of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, 215006, China
| | - Weili Zhang
- Department of Gastroenterology, Xiangcheng People's Hospital, Suzhou, Jiangsu Province, 215131, China
| | - Qiaoming Zhi
- Department of General Surgery, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, 215006, China.
| | - Min Jiang
- Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, 215006, China.
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Kurozumi S, Padilla M, Kurosumi M, Matsumoto H, Inoue K, Horiguchi J, Takeyoshi I, Oyama T, Ranger-Moore J, Allred DC, Dennis E, Nitta H. HER2 intratumoral heterogeneity analyses by concurrent HER2 gene and protein assessment for the prognosis of HER2 negative invasive breast cancer patients. Breast Cancer Res Treat 2016; 158:99-111. [PMID: 27318853 PMCID: PMC4937084 DOI: 10.1007/s10549-016-3856-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 06/04/2016] [Indexed: 02/07/2023]
Abstract
HER2 gene-protein assay (GPA) is a new method for the simultaneous evaluation of HER2 immunohistochemistry (IHC) and HER2 dual in situ hybridization (DISH) on single tissue sections of breast cancer. We investigated the presence of HER2 gene and protein discrepancy and HER2-heterogeneity using HER2-GPA. HER2 status was analyzed for the correlation between the presence of HER2-heterogeneity and patient prognosis. Consecutive 280 invasive breast cancer were examined. Statuses of HER2 protein and gene were evaluated in whole tumor sections of HER2 GPA slides. HER2 protein and gene combination patterns were classified to six phenotypic and genotypic types for each case, as well as at individual cell levels: (A) IHC and DISH positive; (B) IHC positive and DISH negative; (C) IHC equivocal and DISH positive; (D) IHC equivocal and DISH negative; (E) IHC negative and DISH positive; and (F) IHC and DISH negative. The presence of HER2-heterogeneity was determined by the existence of at least two of six types within one tumor. HER2-IHC positive patients had significantly worse survival than IHC negative patients and HER2-DISH positive patients had significantly worse survival than DISH negative patients. HER2 IHC negative and DISH positive patients had significantly worse recurrence-free survival than IHC and DISH negative patients. In the HER2 IHC and DISH negative group, the HER2 heterogeneous group had significantly worse survival than the nonheterogeneous group. Notably, among triple negative breast cancer (TNBC), the HER2 heterogeneous group had significantly worse survival than the nonheterogeneous group. Our study suggests that the presence of HER2-heterogeneity might be a prognostic factor in HER2 negative breast cancer patients, especially in TNBC.
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Affiliation(s)
- Sasagu Kurozumi
- Division of Breast Surgery, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama, Japan
| | - Mary Padilla
- Ventana Medical Systems, Inc., 1910 East Innovation Park Drive, Tucson, AZ, 85755, USA
| | - Masafumi Kurosumi
- Department of Pathology, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan.
| | - Hiroshi Matsumoto
- Division of Breast Surgery, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama, Japan
| | - Kenichi Inoue
- Division of Breast Oncology, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama, Japan
| | - Jun Horiguchi
- Department of Thoracic and Visceral Organ Surgery, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi-city, Gunma, Japan
| | - Izumi Takeyoshi
- Department of Thoracic and Visceral Organ Surgery, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi-city, Gunma, Japan
| | - Tetsunari Oyama
- Department of Diagnostic Pathology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi-city, Gunma, Japan
| | - Jim Ranger-Moore
- Ventana Medical Systems, Inc., 1910 East Innovation Park Drive, Tucson, AZ, 85755, USA
| | - D Craig Allred
- Ventana Medical Systems, Inc., 1910 East Innovation Park Drive, Tucson, AZ, 85755, USA
| | - Eslie Dennis
- Ventana Medical Systems, Inc., 1910 East Innovation Park Drive, Tucson, AZ, 85755, USA
| | - Hiroaki Nitta
- Ventana Medical Systems, Inc., 1910 East Innovation Park Drive, Tucson, AZ, 85755, USA
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15
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Zhou Y, Rucker EB, Zhou BP. Autophagy regulation in the development and treatment of breast cancer. Acta Biochim Biophys Sin (Shanghai) 2016; 48:60-74. [PMID: 26637829 DOI: 10.1093/abbs/gmv119] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 10/21/2015] [Indexed: 12/14/2022] Open
Abstract
Autophagy is a major catabolic process in which intracellular membrane structures, protein complexes, and lysosomes are formed as lysoautophagosome to degrade and renew cytoplasmic components. Autophagy is physiologically a strategy and mechanism for cellular homeostasis as well as adaptation to stress, and thus alterations in the autophagy machinery may lead to diverse pathological conditions. The role of autophagy in cancer is complex, and the current literature reflects this as a 'double-edged sword'. Autophagy shows promise as a novel therapeutic target in various types of breast cancer, inhibiting or increasing treatment efficacy in a context- and cell-type-dependent manner. This review aims to summarize the recent advances in the understanding of the mechanisms by which key modulators of autophagy participate in cancer metastasis, highlight different autophagy-deficient murine models for breast cancer study, and provide further impetus for the modulation of autophagy in anticancer therapy.
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Affiliation(s)
- Yuting Zhou
- Department of Molecular and Cellular Biochemistry, University of Kentucky School of Medicine, Lexington, KY 40506, USA Department of Markey Cancer Center, University of Kentucky School of Medicine, Lexington, KY 40506, USA
| | - Edmund B Rucker
- Department of Biology, University of Kentucky College of Arts and Sciences, Lexington, KY 40506, USA Department of Markey Cancer Center, University of Kentucky School of Medicine, Lexington, KY 40506, USA
| | - Binhua P Zhou
- Department of Molecular and Cellular Biochemistry, University of Kentucky School of Medicine, Lexington, KY 40506, USA Department of Markey Cancer Center, University of Kentucky School of Medicine, Lexington, KY 40506, USA
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16
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Liang DH, El-Zein R, Dave B. Autophagy Inhibition to Increase Radiosensitization in Breast Cancer. ACTA ACUST UNITED AC 2015; 6. [PMID: 26613064 DOI: 10.4172/2155-9619.1000254] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Currently, many breast cancer patients with localized breast cancer undergo breast-conserving therapy, consisting of local excision followed by radiation therapy. Following radiation therapy, breast cancer cells are noted to undergo induction of autophagy, development of radioresistance, and enrichment of breast cancer stem cell subpopulations. It is hypothesized that inhibition of the cytoprotective autophagy that arises following radiation therapy increases radiosensitivity and confers longer relapse-free survival by eliminating tumor-initiating breast cancer stem cells. Therefore, we reviewed the controversial role of autophagy in breast cancer tumorigenesis and progression, autophagy induction by radiotherapy, and utilization of autophagy inhibitors to increase radiosensitivity of breast cancer and to target radioresistant breast cancer stem cells.
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Affiliation(s)
- Diana Hwang Liang
- Department of Surgery, Houston Methodist Hospital, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Randa El-Zein
- Department of Radiology, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Bhuvanesh Dave
- Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, TX 77030, USA
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17
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Rodríguez CE, Reidel SI, Bal de Kier Joffé ED, Jasnis MA, Fiszman GL. Autophagy Protects from Trastuzumab-Induced Cytotoxicity in HER2 Overexpressing Breast Tumor Spheroids. PLoS One 2015; 10:e0137920. [PMID: 26360292 PMCID: PMC4567133 DOI: 10.1371/journal.pone.0137920] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 08/23/2015] [Indexed: 12/15/2022] Open
Abstract
Multicellular tumor spheroids represent a 3D in vitro model that mimics solid tumor essential properties including assembly and development of extracellular matrix and nutrient, oxygen and proliferation gradients. In the present study, we analyze the impact of 3D spatial organization of HER2-overexpressing breast cancer cells on the response to Trastuzumab. We cultured human mammary adenocarcinoma cell lines as spheroids with the hanging drop method and we observed a gradient of proliferating, quiescent, hypoxic, apoptotic and autophagic cells towards the inner core. This 3D organization decreased Trastuzumab sensitivity of HER2 over-expressing cells compared to monolayer cell cultures. We did not observe apoptosis induced by Trastuzumab but found cell arrest in G0/G1 phase. Moreover, the treatment downregulated the basal apoptosis only found in tumor spheroids, by eliciting protective autophagy. We were able to increase sensitivity to Trastuzumab by autophagy inhibition, thus exposing the interaction between apoptosis and autophagy. We confirmed this result by developing a resistant cell line that was more sensitive to autophagy inhibition than the parental BT474 cells. In summary, the development of Trastuzumab resistance relies on the balance between death and survival mechanisms, characteristic of 3D cell organization. We propose the use of spheroids to further improve the understanding of Trastuzumab antitumor activity and overcome resistance.
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Affiliation(s)
- Cristina E. Rodríguez
- Research Area, Institute of Oncology ‘Ángel H. Roffo’, University of Buenos Aires, Buenos Aires, Argentina
| | - Sara I. Reidel
- Industrial Biotechnology Research and Development Center, National Institute of Industrial Technology, Buenos Aires, Argentina
| | - Elisa D. Bal de Kier Joffé
- Research Area, Institute of Oncology ‘Ángel H. Roffo’, University of Buenos Aires, Buenos Aires, Argentina
| | - Maria A. Jasnis
- Research Area, Institute of Oncology ‘Ángel H. Roffo’, University of Buenos Aires, Buenos Aires, Argentina
| | - Gabriel L. Fiszman
- Research Area, Institute of Oncology ‘Ángel H. Roffo’, University of Buenos Aires, Buenos Aires, Argentina
- Industrial Biotechnology Research and Development Center, National Institute of Industrial Technology, Buenos Aires, Argentina
- * E-mail:
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18
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Jung YY, Lee YK, Koo JS. The potential of Beclin 1 as a therapeutic target for the treatment of breast cancer. Expert Opin Ther Targets 2015; 20:167-78. [PMID: 26357854 DOI: 10.1517/14728222.2016.1085971] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
INTRODUCTION Beclin 1 plays a crucial role in autophagy via the Beclin 1 interactome, and is involved in various biological processes such as protein sorting, chemokinesis, and cell death. Via these biologic functions, Beclin 1 contributes to both tumor suppression and tumor progression. AREAS COVERED Beclin 1 plays a key biologic function on cell homeostasis and affects tumorigenesis. In this review, detailing up-to-date knowledge on the tumorigenic role of Beclin 1, its implication in breast cancer, and its utility as a breast cancer-specific drug target is discussed. EXPERT OPINION Because Beclin 1 is expressed in breast cancer cells, Beclin 1 could be a unique, effective drug target for the prevention and treatment of breast cancer. However, the expression of Beclin 1 varies according to cancer molecular subtypes, and Beclin 1 is involved in both breast cancer suppression and tumor progression; therefore, the decision of using a Beclin 1 inducer or inhibitor should be made based on breast cancer stage and subtype.
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Affiliation(s)
- Yoon Yang Jung
- a Yonsei University College of Medicine, Severance Hospital, Department of Pathology , 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea ;
| | - Yu Kyung Lee
- a Yonsei University College of Medicine, Severance Hospital, Department of Pathology , 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea ;
| | - Ja Seung Koo
- a Yonsei University College of Medicine, Severance Hospital, Department of Pathology , 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea ;
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19
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Shen M, Duan WM, Wu MY, Wang WJ, Liu L, Xu MD, Zhu J, Li DM, Gui Q, Lian L, Gong FR, Chen K, Li W, Tao M. Participation of autophagy in the cytotoxicity against breast cancer cells by cisplatin. Oncol Rep 2015; 34:359-67. [PMID: 26005215 DOI: 10.3892/or.2015.4005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 04/30/2015] [Indexed: 11/05/2022] Open
Abstract
Breast cancer is one of the most common cancers affecting women worldwide. Conventional chemotherapy is still one of the major approaches to the treatment of breast cancer. Autophagy, also termed as type II programmed cell death (PCD), exhibits either a protumorigenic or antitumorigenic function. In the present study, we investigated whether autophagy could be involved in the effect of chemotherapy against breast cancer. Epirubicin, docetaxel, methotrexate, cyclophosphamide, fluorouracil (5-FU) and cisplatin were applied in the present investigation. All of these chemotherapeutics presented cytotoxicity against breast cancer cells. DsRed-LC3 reporter assay revealed that only docetaxel and cisplatin induced autophagy. Autophagy inhibitor 3-methyladenine (3-MA) strengthened the cytotoxicity of docetaxel, yet impaired the cytotoxicity of cisplatin, suggesting that docetaxel stimulates protumorigenic autophagy, while cisplatin-induced autophagy could be antitumorigenic. Real-time PCR revealed that cisplatin upregulated multiple autophagy-related genes, including AMBRA1, ATG3, ATG4C, ATG4D, ATG5, ATG7, ATG13, ATG14, ATG16L2, Beclin1, DRAM1, GABARAP, GABARAPL1, GABARAPL2, HDAC6, IRGM, MAP1LC3B and ULK1, indicating that cisplatin induced autophagy through a multiple mechanism involved manner.
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Affiliation(s)
- Meng Shen
- Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Wei-Ming Duan
- Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Meng-Yao Wu
- Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Wen-Jie Wang
- Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Lu Liu
- Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Meng-Dan Xu
- Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Jie Zhu
- Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Dao-Ming Li
- Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Qi Gui
- Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Lian Lian
- Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Fei-Ran Gong
- Department of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Kai Chen
- Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Wei Li
- Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Min Tao
- Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
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20
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Tang H, Sebti S, Titone R, Zhou Y, Isidoro C, Ross TS, Hibshoosh H, Xiao G, Packer M, Xie Y, Levine B. Decreased BECN1 mRNA Expression in Human Breast Cancer is Associated with Estrogen Receptor-Negative Subtypes and Poor Prognosis. EBioMedicine 2015; 2:255-263. [PMID: 25825707 PMCID: PMC4376376 DOI: 10.1016/j.ebiom.2015.01.008] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Both BRCA1 and Beclin 1 (BECN1) are tumor suppressor genes, which are in close proximity on the human chromosome 17q21 breast cancer tumor susceptibility locus and are often concurrently deleted. However, their importance in sporadic human breast cancer is not known. To interrogate the effects of BECN1 and BRCA1 in breast cancer, we studied their mRNA expression patterns in breast cancer patients from two large datasets: The Cancer Genome Atlas (TCGA) (n = 1067) and the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) (n = 1992). In both datasets, low expression of BECN1 was more common in HER2-enriched and basal-like (mostly triple-negative) breast cancers compared to luminal A/B intrinsic tumor subtypes, and was also strongly associated with TP53 mutations and advanced tumor grade. In contrast, there was no significant association between low BRCA1 expression and HER2-enriched or basal-like subtypes, TP53 mutations or tumor grade. In addition, low expression of BECN1 (but not low BRCA1) was associated with poor prognosis, and BECN1 (but not BRCA1) expression was an independent predictor of survival. These findings suggest that decreased mRNA expression of the autophagy gene BECN1 may contribute to the pathogenesis and progression of HER2-enriched, basal-like, and TP53 mutant breast cancers. The tumor suppressor genes, BECN1 and BRCA1, are in close proximity to the 17q21 breast cancer tumor susceptibility locus. We studied mRNA expression patterns of BECN1 and BRCA1 in breast cancer patients in the large TCGA and METABRIC datasets. Decreased BECN1 (but not BRCA1) expression is linked with aggressive clinico-pathological features in human breast cancer. Decreased BECN1 (but not BRCA1) expression is linked with worse survival in human breast cancer patients.
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Affiliation(s)
- Hao Tang
- Department of Clinical Sciences, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Salwa Sebti
- Center for Autophagy Research, University of Texas Southwestern Medical Center, Dallas, Texas 75390 ; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Rossella Titone
- Center for Autophagy Research, University of Texas Southwestern Medical Center, Dallas, Texas 75390 ; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Yunyun Zhou
- Department of Clinical Sciences, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Ciro Isidoro
- Laboratory of Molecular Pathology and Nanobioimaging, Department of Health Sciences, Università del Piemonte Orientale "A Avogrado", Via Solaroli 17, 28100 Novara, Italy
| | - Theodora S Ross
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas 75390 ; Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Hanina Hibshoosh
- Department of Pathology and Cell Biology, Columbia University College of Physicians & Surgeons, New York, New York 10032
| | - Guanghua Xiao
- Department of Clinical Sciences, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Milton Packer
- Department of Clinical Sciences, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Yang Xie
- Department of Clinical Sciences, University of Texas Southwestern Medical Center, Dallas, Texas 75390 ; Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Beth Levine
- Center for Autophagy Research, University of Texas Southwestern Medical Center, Dallas, Texas 75390 ; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas 75390 ; Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas 75390 ; Howard Hughes Medical Research Institute, University of Texas Southwestern Medical Center, Dallas, Texas 75390
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21
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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: 52] [Impact Index Per Article: 5.2] [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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22
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Martinez-Outschoorn U, Sotgia F, Lisanti MP. Tumor microenvironment and metabolic synergy in breast cancers: critical importance of mitochondrial fuels and function. Semin Oncol 2014; 41:195-216. [PMID: 24787293 DOI: 10.1053/j.seminoncol.2014.03.002] [Citation(s) in RCA: 144] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Metabolic synergy or metabolic coupling between glycolytic stromal cells (Warburg effect) and oxidative cancer cells occurs in human breast cancers and promotes tumor growth. The Warburg effect or aerobic glycolysis is the catabolism of glucose to lactate to obtain adenosine triphosphate (ATP). This review summarizes the main findings on this stromal metabolic phenotype, and the associated signaling pathways, as well as the critical role of oxidative stress and autophagy, all of which promote carcinoma cell mitochondrial metabolism and tumor growth. Loss of Caveolin 1 (Cav-1) and the upregulation of monocarboxylate transporter 4 (MCT4) in stromal cells are novel markers of the Warburg effect and metabolic synergy between stromal and carcinoma cells. MCT4 and Cav-1 are also breast cancer prognostic biomarkers. Reactive oxygen species (ROS) are key mediators of the stromal Warburg effect. High ROS also favors cancer cell mitochondrial metabolism and tumorigenesis, and anti-oxidants can reverse this altered stromal and carcinoma metabolism. A pseudo-hypoxic state with glycolysis and low mitochondrial metabolism in the absence of hypoxia is a common feature in breast cancer. High ROS induces loss of Cav-1 in stromal cells and is sufficient to generate a pseudo-hypoxic state. Loss of Cav-1 in the stroma drives glycolysis and lactate extrusion via HIF-1α stabilization and the upregulation of MCT4. Stromal cells with loss of Cav-1 and/or high expression of MCT4 also show a catabolic phenotype, with enhanced macroautophagy. This catabolic state in stromal cells is driven by hypoxia-inducible factor (HIF)-1α, nuclear factor κB (NFκB), and JNK activation and high ROS generation. A feed-forward loop in stromal cells regulates pseudo-hypoxia and metabolic synergy, with Cav-1, MCT4, HIF-1α, NFκB, and ROS as its key elements. Metabolic synergy also may occur between cancer cells and cells in distant organs from the tumor. Cancer cachexia, which is due to severe organismal metabolic dysregulation in myocytes and adipocytes, shares similarities with stromal-carcinoma metabolic synergy, as well. In summary, metabolic synergy occurs when breast carcinoma cells induce a nutrient-rich microenvironment to promote tumor growth. The process of tumor metabolic synergy is a multistep process, due to the generation of ROS, and the induction of catabolism with autophagy, mitophagy and glycolysis. Studying epithelial-stromal interactions and metabolic synergy is important to better understand the ecology of cancer and the metabolic role of different cell types in tumor progression.
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Affiliation(s)
| | - Federica Sotgia
- University of Manchester, Manchester Breast Centre & Breakthrough Breast Cancer Research Unit, Manchester, United Kingdom
| | - Michael P Lisanti
- University of Manchester, Manchester Breast Centre & Breakthrough Breast Cancer Research Unit, Manchester, United Kingdom
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23
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Lozy F, Cai-McRae X, Teplova I, Price S, Reddy A, Bhanot G, Ganesan S, Vazquez A, Karantza V. ERBB2 overexpression suppresses stress-induced autophagy and renders ERBB2-induced mammary tumorigenesis independent of monoallelic Becn1 loss. Autophagy 2014; 10:662-76. [PMID: 24492513 PMCID: PMC4091153 DOI: 10.4161/auto.27867] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Defective autophagy has been implicated in mammary tumorigenesis, as the gene encoding the essential autophagy regulator BECN1 is deleted in human breast cancers and Becn1+/− mice develop mammary hyperplasias. In agreement with a recent study, which reports concurrent allelic BECN1 loss and ERBB2 amplification in a small number of human breast tumors, we found that low BECN1 mRNA correlates with ERBB2-overexpression in breast cancers, suggesting that BECN1 loss and ERBB2 overexpression may functionally interact in mammary tumorigenesis. We now report that ERBB2 overexpression suppressed autophagic response to stress in mouse mammary and human breast cancer cells. ERBB2-overexpressing Becn1+/+ and Becn1+/− immortalized mouse mammary epithelial cells (iMMECs) formed mammary tumors in nude mice with similar kinetics, and monoallelic Becn1 loss did not alter ERBB2- and PyMT-driven mammary tumorigenesis. In human breast cancer databases, ERBB2-expressing tumors exhibit a low autophagy gene signature, independent of BECN1 mRNA expression, and have similar gene expression profiles with non-ERBB2-expressing breast tumors with low BECN1 levels. We also found that ERBB2-expressing BT474 breast cancer cells, despite being partially autophagy-deficient under stress, can be sensitized to the anti-ERBB2 antibody trastuzumab (tzb) by further pharmacological or genetic autophagy inhibition. Our results indicate that ERBB2-driven mammary tumorigenesis is associated with functional autophagy suppression and ERBB2-positive breast cancers are partially autophagy-deficient even in a wild-type BECN1 background. Furthermore and extending earlier findings using tzb-resistant cells, exogenously imposed autophagy inhibition increases the anticancer effect of trastuzumab on tzb-sensitive ERBB2-expressing breast tumor cells, indicating that pharmacological autophagy suppression has a wider role in the treatment of ERBB2-positive breast cancer.
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Affiliation(s)
- Fred Lozy
- Rutgers University; State University of New Jersey; New Brunswick, NJ USA; Rutgers Cancer Institute of New Jersey; New Brunswick, NJ USA
| | - Xiaofeng Cai-McRae
- Rutgers University; State University of New Jersey; New Brunswick, NJ USA; Rutgers Cancer Institute of New Jersey; New Brunswick, NJ USA
| | - Irina Teplova
- Rutgers University; State University of New Jersey; New Brunswick, NJ USA; Rutgers Cancer Institute of New Jersey; New Brunswick, NJ USA
| | - Sandy Price
- Rutgers University; State University of New Jersey; New Brunswick, NJ USA; Rutgers Cancer Institute of New Jersey; New Brunswick, NJ USA
| | - Anupama Reddy
- Rutgers University; State University of New Jersey; New Brunswick, NJ USA
| | - Gyan Bhanot
- Rutgers University; State University of New Jersey; New Brunswick, NJ USA; Rutgers Cancer Institute of New Jersey; New Brunswick, NJ USA
| | - Shridar Ganesan
- Rutgers University; State University of New Jersey; New Brunswick, NJ USA; Rutgers Cancer Institute of New Jersey; New Brunswick, NJ USA; Division of Medical Oncology; Department of Internal Medicine; Rutgers Robert Wood Johnson Medical School; Piscataway, NJ USA
| | - Alexei Vazquez
- Rutgers University; State University of New Jersey; New Brunswick, NJ USA; Rutgers Cancer Institute of New Jersey; New Brunswick, NJ USA
| | - Vassiliki Karantza
- Rutgers University; State University of New Jersey; New Brunswick, NJ USA; Rutgers Cancer Institute of New Jersey; New Brunswick, NJ USA; Division of Medical Oncology; Department of Internal Medicine; Rutgers Robert Wood Johnson Medical School; Piscataway, NJ USA
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24
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Cufí S, Vazquez-Martin A, Oliveras-Ferraros C, Corominas-Faja B, Urruticoechea A, Martin-Castillo B, Menendez JA. Autophagy-related gene 12 (ATG12) is a novel determinant of primary resistance to HER2-targeted therapies: utility of transcriptome analysis of the autophagy interactome to guide breast cancer treatment. Oncotarget 2013; 3:1600-14. [PMID: 23307622 PMCID: PMC3681498 DOI: 10.18632/oncotarget.742] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The autophagic process, which can facilitate breast cancer resistance to endocrine, cytotoxic,
and molecularly targeted agents, is mainly regulated at the post-translational level. Although
recent studies have suggested a possible transcriptome regulation of the autophagic genes, little is
known about either the analysis tools that can be applied or the functional importance of putative
candidate genes emerging from autophagy-dedicated transcriptome studies. In this context, we
evaluated whether the constitutive activation of the autophagy machinery, as revealed by a
transcriptome analysis using an autophagy-focused polymerase chain reaction (PCR) array, might allow
for the identification of novel autophagy-specific biomarkers for intrinsic (primary) resistance to
HER2-targeted therapies. Quantitative real-time PCR (qRT-PCR)-based profiling of 84 genes involved
in autophagy revealed that, when compared to trastuzumab-sensitive SKBR3 cells, the positive
regulator of autophagic vesicle formation ATG12 (autophagy-related gene 12) was the
most differentially up-regulated gene in JIMT1 cells, a model of intrinsic cross-resistance to
trastuzumab and other HER1/2-targeting drugs. An analysis of the transcriptional status of
ATG12 in > 50 breast cancer cell lines suggested that the
ATG12 transcript is commonly upregulated in trastuzumab-unresponsive
HER2-overexpressing breast cancer cells. A lentiviral-delivered small hairpin RNA stable knockdown
of the ATG12 gene fully suppressed the refractoriness of JIMT1 cells to
trastuzumab, erlotinib, gefitinib, and lapatinib in vitro. ATG12 silencing
significantly reduced JIMT1 tumor growth induced by subcutaneous injection in nude mice. Remarkably,
the outgrowth of trastuzumab-unresponsive tumors was prevented completely when trastuzumab treatment
was administered in an ATG12-silenced genetic background. We demonstrate for the
first time the usefulness of low-density, autophagy-dedicated qRT-PCR-based platforms for monitoring
primary resistance to HER2-targeted therapies by transcriptionally screening the autophagy
interactome. The degree of predictive accuracy warrants further investigation in the clinical
situation.
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Affiliation(s)
- Sílvia Cufí
- Metabolism and Cancer Group, Translational Research Laboratory, Catalan Institute of Oncology-Girona, ICO-Girona
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25
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Autophagy and genomic integrity. Cell Death Differ 2013; 20:1444-54. [PMID: 23933813 DOI: 10.1038/cdd.2013.103] [Citation(s) in RCA: 123] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 06/07/2013] [Accepted: 07/02/2013] [Indexed: 01/25/2023] Open
Abstract
DNA lesions, constantly produced by endogenous and exogenous sources, activate the DNA damage response (DDR), which involves detection, signaling and repair of the damage. Autophagy, a lysosome-dependent degradation pathway that is activated by stressful situations such as starvation and oxidative stress, regulates cell fate after DNA damage and also has a pivotal role in the maintenance of nuclear and mitochondrial genomic integrity. Here, we review important evidence regarding the role played by autophagy in preventing genomic instability and tumorigenesis, as well as in micronuclei degradation. Several pathways governing autophagy activation after DNA injury and the influence of autophagy upon the processing of genomic lesions are also discussed herein. In this line, the mechanisms by which several proteins participate in both DDR and autophagy, and the importance of this crosstalk in cancer and neurodegeneration will be presented in an integrated fashion. At last, we present a hypothetical model of the role played by autophagy in dictating cell fate after genotoxic stress.
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26
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Choi J, Jung W, Koo JS. Expression of autophagy-related markers beclin-1, light chain 3A, light chain 3B and p62 according to the molecular subtype of breast cancer. Histopathology 2012; 62:275-86. [PMID: 23134379 DOI: 10.1111/his.12002] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
AIMS To investigate the relationship between the expression of autophagy-related proteins, including beclin-1, light chain (LC) 3A, LC3B, and p62, and prognosis in invasive breast cancer. METHODS AND RESULTS We constructed tissue microarrays from the breast cancer cells of 489 patients, and classified molecular subtypes using surrogate immunohistochemical stains. The tumoral expression levels of LC3A and LC3B were highest in triple-negative breast cancer (TNBC) (P < 0.001), whereas these types of tumour had the lowest expression levels of these markers in the stroma (P = 0.005 and P < 0.001, respectively). Cytoplasmic beclin-1 expression was highest in TNBC, but nuclear expression was lowest (P < 0.001). p62 cytoplasmic and nuclear expression were highest in HER2-type tumours (P = 0.001 and P < 0.001, respectively). Tumoral LC3A and LC3B expression were associated with high histological grade (P < 0.001, and P < 0.028, respectively), but nuclear p62 expression was associated with lower histological grade (P = 0.004). CONCLUSIONS Autophagy-related markers are differentially expressed according to the molecular subtype of breast cancer. In particular, expression of LC3A, LC3B and beclin-1 was highest in TNBC tumour cells, whereas that of LC3A and LC3B in the tumour stroma was lowest in TNBC.
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Affiliation(s)
- Junjeong Choi
- Department of Pathology, Yonsei University Wonju College of Medicine, Wonju Department of Pathology, Yonsei University College of Medicine, Seoul, South Korea
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27
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Swampillai A, Salomoni P, Short S. The Role of Autophagy in Clinical Practice. Clin Oncol (R Coll Radiol) 2012; 24:387-95. [DOI: 10.1016/j.clon.2011.09.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 08/22/2011] [Accepted: 08/23/2011] [Indexed: 01/07/2023]
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Lebovitz CB, Bortnik SB, Gorski SM. Here, there be dragons: charting autophagy-related alterations in human tumors. Clin Cancer Res 2012; 18:1214-26. [PMID: 22253413 DOI: 10.1158/1078-0432.ccr-11-2465] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Macroautophagy (or autophagy) is a catabolic cellular process that is both homeostatic and stress adaptive. Normal cells rely on basal levels of autophagy to maintain cellular integrity (via turnover of long-lived proteins and damaged organelles) and increased levels of autophagy to buoy cell survival during various metabolic stresses (via nutrient and energy provision through lysosomal degradation of cytoplasmic components). Autophagy can function in both tumor suppression and tumor progression, and is under investigation in clinical trials as a novel target for anticancer therapy. However, its role in cancer pathogenesis has yet to be fully explored. In particular, it remains unknown whether in vitro observations will be applicable to human cancer patients. Another outstanding question is whether there exists tumor-specific selection for alterations in autophagy function. In this review, we survey reported mutations in autophagy genes and key autophagy regulators identified in human tumor samples and summarize the literature regarding expression levels of autophagy genes and proteins in various cancer tissues. Although it is too early to draw inferences from this collection of in vivo studies of autophagy-related alterations in human cancers, their results highlight the challenges that must be overcome before we can accurately assess the scope of autophagy's predicted role in tumorigenesis.
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Affiliation(s)
- Chandra B Lebovitz
- Genome Sciences Centre, BC Cancer Agency, University of British Columbia, Vancouver, Canada
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29
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Cook KL, Shajahan AN, Clarke R. Autophagy and endocrine resistance in breast cancer. Expert Rev Anticancer Ther 2012; 11:1283-94. [PMID: 21916582 DOI: 10.1586/era.11.111] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The American Cancer Society estimates that over 200,000 new breast cancer cases are diagnosed annually in the USA alone. Of these cases, the majority are invasive breast cancers and almost 70% are estrogen receptor-α positive. Therapies targeting the estrogen receptor-α are widely applied and include selective estrogen receptor modulators such as tamoxifen, a selective estrogen receptor downregulator such as Fulvestrant (Faslodex; FAS, ICI 182,780), or one of the third-generation aromatase inhibitors including letrozole or anastrozole. While these treatments reduce breast cancer mortality, many estrogen receptor-α-positive tumors eventually recur, highlighting the clinical significance of endocrine therapy resistance. The signaling leading to endocrine therapy resistance is poorly understood; however, preclinical studies have established an important role for autophagy in the acquired resistance phenotype. Autophagy is a cellular degradation process initiated in response to stress or nutrient deprivation, which attempts to restore metabolic homeostasis through the catabolic lysis of aggregated proteins, unfolded/misfolded proteins or damaged subcellular organelles. The duality of autophagy, which can be either pro-survival or pro-death, is well known. However, in the context of endocrine therapy resistance in breast cancer, the inhibition of autophagy can potentiate resensitization of previously antiestrogen resistant breast cancer cells. In this article, we discuss the complex and occasionally contradictory roles of autophagy in cancer and in resistance to endocrine therapies in breast cancer.
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Affiliation(s)
- Katherine L Cook
- Department of Oncology and Lombardi Comprehensive Cancer Center W405A Research Building, Georgetown University Medical Center, 3970 Reservoir Road NW, Washington, DC 20057, USA.
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30
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Debnath J. The multifaceted roles of autophagy in tumors-implications for breast cancer. J Mammary Gland Biol Neoplasia 2011; 16:173-87. [PMID: 21779879 PMCID: PMC3170851 DOI: 10.1007/s10911-011-9223-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Accepted: 06/23/2011] [Indexed: 12/21/2022] Open
Abstract
Autophagy is an evolutionarily conserved lysosomal degradation process that is crucial for adaptation to stress as well as in cellular homeostasis. In cancer, our current understanding has uncovered multifaceted roles for autophagy in tumor initiation and progression. Although genetic evidence corroborates a critical role for autophagy as a tumor suppressor mechanism, autophagy can also promote the survival and fitness of advanced tumors subject to stress, which has important implications during breast cancer progression and metastasis. Here, I discuss the mechanisms and the evidence underlying these diverse roles for autophagy in cancer and speculate on specific circumstances in which autophagy can be most effectively targeted for breast cancer treatment.
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Affiliation(s)
- Jayanta Debnath
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, 513 Parnassus Ave, HSW450B, San Francisco, CA 94143, USA.
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31
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Wu WKK, Coffelt SB, Cho CH, Wang XJ, Lee CW, Chan FKL, Yu J, Sung JJY. The autophagic paradox in cancer therapy. Oncogene 2011; 31:939-53. [PMID: 21765470 DOI: 10.1038/onc.2011.295] [Citation(s) in RCA: 180] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Autophagy, hallmarked by the formation of double-membrane bound organelles known as autophagosomes, is a lysosome-dependent pathway for protein degradation. The role of autophagy in carcinogenesis is context dependent. As a tumor-suppressing mechanism in early-stage carcinogenesis, autophagy inhibits inflammation and promotes genomic stability. Moreover, disruption of autophagy-related genes accelerates tumorigenesis in animals. However, autophagy may also act as a pro-survival mechanism to protect cancer cells from various forms of cellular stress. In cancer therapy, adaptive autophagy in cancer cells sustains tumor growth and survival in face of the toxicity of cancer therapy. To this end, inhibition of autophagy may sensitize cancer cells to chemotherapeutic agents and ionizing radiation. Nevertheless, in certain circumstances, autophagy mediates the therapeutic effects of some anticancer agents. Data from recent studies are beginning to unveil the apparently paradoxical nature of autophagy as a cell-fate decision machinery. Taken together, modulation of autophagy is a novel approach for enhancing the efficacy of existing cancer therapy, but its Janus-faced nature may complicate the clinical development of autophagy modulators as anticancer therapeutics.
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Affiliation(s)
- W K K Wu
- Institute of Digestive Diseases, LKS Institute of Health Sciences and Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, China.
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32
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Sridharan S, Jain K, Basu A. Regulation of autophagy by kinases. Cancers (Basel) 2011; 3:2630-54. [PMID: 24212825 PMCID: PMC3757434 DOI: 10.3390/cancers3022630] [Citation(s) in RCA: 145] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 05/15/2011] [Accepted: 05/27/2011] [Indexed: 12/16/2022] Open
Abstract
Autophagy is a process of self-degradation that maintains cellular viability during periods of metabolic stress. Although autophagy is considered a survival mechanism when faced with cellular stress, extensive autophagy can also lead to cell death. Aberrations in autophagy are associated with several diseases, including cancer. Therapeutic exploitation of this process requires a clear understanding of its regulation. Although the core molecular components involved in the execution of autophagy are well studied there is limited information on how cellular signaling pathways, particularly kinases, regulate this complex process. Protein kinases are integral to the autophagy process. Atg1, the first autophagy-related protein identified, is a serine/threonine kinase and it is regulated by another serine/threonine kinase mTOR. Emerging studies suggest the participation of many different kinases in regulating various components/steps of this catabolic process. This review focuses on the regulation of autophagy by several kinases with particular emphasis on serine/threonine protein kinases such as mTOR, AMP-activated protein kinase, Akt, mitogen-activated protein kinase (ERK, p38 and JNK) and protein kinase C that are often deregulated in cancer and are important therapeutic targets.
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Affiliation(s)
- Savitha Sridharan
- Department of Molecular Biology and Immunology, University of North Texas Health Science Center and Institute for Cancer Research, Fort Worth, TX 76107, USA.
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Vazquez-Martin A, López-Bonetc E, Cufí S, Oliveras-Ferraros C, Del Barco S, Martin-Castillo B, Menendez JA. Repositioning chloroquine and metformin to eliminate cancer stem cell traits in pre-malignant lesions. Drug Resist Updat 2011; 14:212-23. [PMID: 21600837 DOI: 10.1016/j.drup.2011.04.003] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Revised: 04/19/2011] [Accepted: 04/20/2011] [Indexed: 01/07/2023]
Abstract
Ideal oncology drugs would be curative after a short treatment course if they could eliminate epithelium-originated carcinomas at their non-invasive, pre-malignant stages. Such ideal molecules, which are expected to molecularly abrogate all the instrumental mechanisms acquired by migrating cancer stem cells (CSCs) to by-pass tumour suppressor barriers, might already exist. We here illustrate how system biology strategies for repositioning existing FDA-approved drugs may accelerate our therapeutic capacity to eliminate CSC traits in pre-invasive intraepithelial neoplasias. First, we describe a signalling network signature that overrides bioenergetics stress- and oncogene-induced senescence (OIS) phenomena in CSCs residing at pre-invasive lesions. Second, we functionally map the anti-malarial chloroquine and the anti-diabetic metformin ("old drugs") to their recently recognized CSC targets ("new uses") within the network. By discussing the preclinical efficacy of chloroquine and metformin to inhibiting the genesis and self-renewal of CSCs we finally underscore the expected translational impact of the "old drugs-new uses" repurposing strategy to open a new CSC-targeted chemoprevention era.
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Affiliation(s)
- Alejandro Vazquez-Martin
- Unit of Translational Research, Catalan Institute of Oncology-Girona, Avenida de Francia s/n, E-17007 Girona, Catalonia, Spain
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