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Fang YX, Lu EQ, Xu E, Zhang YY, Zhu M. Arf1 promotes porcine intestinal epithelial cell proliferation via the mTORC1 signaling pathway. In Vitro Cell Dev Biol Anim 2024:10.1007/s11626-024-00942-y. [PMID: 39093368 DOI: 10.1007/s11626-024-00942-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 06/20/2024] [Indexed: 08/04/2024]
Abstract
The promotion of gut health, a pervasive problem in modern animal husbandry, positively affects organismal health, productivity, and economics. Porcine intestinal epithelial cells (IPEC-J2) continuously proliferate to maintain intestinal homeostasis, including barrier, immune, and absorptive functions. Gut homeostasis is fundamental to organismal health. ADP-ribosylation factor 1 (Arf1), a small GTPase, plays a crucial role in coordinating mTORC1 in response to nutrients, especially amino acid availability in the gut. mTORC1 is the central hub of proliferation. Thus, it seems likely that Arf1 promotes IPEC-J2 cell proliferation. However, the exact role of Arf1 in the porcine gut remains unclear. Therefore, we evaluated the functional role and possible mechanisms of Arf1 in the porcine intestine through Arf1 overexpression and knockdown in IPEC-J2 cells. Arf1 overexpression and knockdown significantly enhanced and inhibited, respectively, IPEC-J2 cell viability, and PCNA expression varied with Arf1 expression. Moreover, the proportion of Ki67-positive cells was significantly greater in the Arf1-overexpressing group than in the control group. These results suggest that Arf1 improves IPEC-J2 cell proliferation. The underlying mechanism was explored by Western blotting. Arf1 overexpression and knockdown significantly enhanced and suppressed, respectively, the levels of p-S6K1 and p-RPS6, which are key downstream targets of the mTORC1 signaling pathway. Collectively, our findings reveal the role of the Arf1-mTORC1 axis in IPEC-J2 cell proliferation and its potential function in regulating intestinal homeostasis and health.
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Affiliation(s)
- Yong-Xia Fang
- Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, College of Animal Science, Guizhou University, Guiyang, 550025, Guizhou Province, China
- Institute of Animal Nutrition and Feed Science, Guizhou University, Guiyang, 550025, China
| | - En-Qing Lu
- Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, College of Animal Science, Guizhou University, Guiyang, 550025, Guizhou Province, China
- Institute of Animal Nutrition and Feed Science, Guizhou University, Guiyang, 550025, China
| | - E Xu
- Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, College of Animal Science, Guizhou University, Guiyang, 550025, Guizhou Province, China
- Institute of Animal Nutrition and Feed Science, Guizhou University, Guiyang, 550025, China
| | - Yi-Yu Zhang
- Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, College of Animal Science, Guizhou University, Guiyang, 550025, Guizhou Province, China
- Institute of Animal Nutrition and Feed Science, Guizhou University, Guiyang, 550025, China
| | - Min Zhu
- Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, College of Animal Science, Guizhou University, Guiyang, 550025, Guizhou Province, China.
- Institute of Animal Nutrition and Feed Science, Guizhou University, Guiyang, 550025, China.
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Suarez-Henriques P, Miranda E Silva-Chaves CD, Cardoso-Leite R, Guilermo-Ferreira R, Katiki LM, Louvandini H. Exploring AMH levels, homeostasis parameters, and ovarian primordial follicle activation in pubertal infected sheep on a high-protein diet. Res Vet Sci 2024; 169:105158. [PMID: 38295629 DOI: 10.1016/j.rvsc.2024.105158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 01/09/2024] [Accepted: 01/17/2024] [Indexed: 02/02/2024]
Abstract
"Exploring AMH Levels, Homeostasis and Primordial Follicle Activation in Pubertal Infected Sheep on a High Protein Diet ". The first activation wave of ovarian primordial follicles is part of the onset of puberty and fertility. Abomasal helminth infection may cause an undesirable delay in puberty manifestation. Helminth-infected animals demand a higher amount of protein in their diet to repair the damage caused by the parasite in sheep's tissues, replenish the blood losses, and build the host's immune response. Helminths become resistant to drug therapy shortly after being exposed to a new treatment. Besides, there is the possibility of contamination by anthelmintic drugs in ovine products, possibly affecting human health and the environment. This study's objective was to evaluate if ovarian and clinical parameters can be improved by supplementing their diet with protein, offering a more sustainable management approach than relying on anthelmintic usage. We used a 2 × 2 factorial model where eighteen ewe lambs (Ovis aries) between 6 and 7 months old - born to the same ram - were fed one of two diet protein levels (12% or 19%). After 35 days on this diet, they were infected or left uninfected with 10,000 Haemonchus contortus L3 larvae. We evaluated Anti-Mullerian Hormone serum levels, blood cells and biochemical parameters at four different time points. Following 42 days of infection and 77 days on the diet, the lambs had their left ovaries removed, and we examined ovarian morphometrics through histological analysis. The groups Supplemented Protein-Infected(n = 5), Control Protein- Infected(n = 5), Supplemented Protein-Not Infected (n = 4) and Control Protein-Not Infected (n = 4) did not differ in their bodyweight gain. In the factorial ANOVA analysis examining the relationship between plasma protein, diet, and infection, the protein level of the diet showed significance (p = 0.02). Primordial follicle size varied with the interaction between diet and infection (p < 0.05), and oocyte size was affected by the level of protein in the diet (p = 0.047). Additionally, to understand how all homeostasis parameters relate to the primordial follicle and oocyte size, we applied an explanatory linear mixed model. In conclusion, serum AMH levels remained stable despite the infection and variations in diet protein levels, indicating its reliability as a marker for ovarian reserve in pubertal sheep. The number of blood cells, biochemical parameters, and primordial follicle activation were affected by both diet and infection.
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Affiliation(s)
- Paula Suarez-Henriques
- Animal Science Department, ESALQ, University of São Paulo, Piracicaba, São Paulo, Brazil.
| | - Camila De Miranda E Silva-Chaves
- Laboratory of Animal Nutrition - Centre for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, Brazil
| | | | - Rhainer Guilermo-Ferreira
- Biological Science Department, Federal University of Triangulo Mineiro, Uberaba, Minas Gerais, Brazil.
| | | | - Hélder Louvandini
- Laboratory of Animal Nutrition - Centre for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, São Paulo, Brazil.
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Bernardini I, Quagliariello A, Peruzza L, Martino ME, Dalla Rovere G, Iori S, Asnicar D, Ciscato M, Fabrello J, Corami F, Cecchetto M, Giubilato E, Carrer C, Bettiol C, Semenzin E, Marcomini A, Matozzo V, Bargelloni L, Milan M, Patarnello T. Contaminants from dredged sediments alter the transcriptome of Manila clam and induce shifts in microbiota composition. BMC Biol 2023; 21:234. [PMID: 37880625 PMCID: PMC10601118 DOI: 10.1186/s12915-023-01741-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 10/17/2023] [Indexed: 10/27/2023] Open
Abstract
BACKGROUND The reuse of dredged sediments in ports and lagoons is a big issue as it should not affect the quality and the equilibrium of ecosystems. In the lagoon of Venice, sediment management is of crucial importance as sediments are often utilized to built-up structures necessary to limit erosion. However, the impact of sediment reuse on organisms inhabiting this delicate area is poorly known. The Manila clam is a filter-feeding species of high economic and ecological value for the Venice lagoon experiencing a drastic decline in the last decades. In order to define the molecular mechanisms behind sediment toxicity, we exposed clams to sediments sampled from different sites within one of the Venice lagoon navigable canals close to the industrial area. Moreover, we investigated the impacts of dredged sediments on clam's microbial communities. RESULTS Concentrations of the trace elements and organic chemicals showed increasing concentrations from the city of Venice to sites close to the industrial area of Porto Marghera, where PCDD/Fs and PCBs concentrations were up to 120 times higher than the southern lagoon. While bioaccumulation of organic contaminants of industrial origin reflected sediments' chemical concentrations, metal bioaccumulation was not consistent with metal concentrations measured in sediments probably due to the activation of ABC transporters. At the transcriptional level, we found a persistent activation of the mTORC1 signalling pathway, which is central in the coordination of cellular responses to chemical stress. Microbiota characterization showed the over-representation of potential opportunistic pathogens following exposure to the most contaminated sediments, leading to host immune response activation. Despite the limited acquisition of new microbial species from sediments, the latter play an important role in shaping Manila clam microbial communities. CONCLUSIONS Sediment management in the Venice lagoon will increase in the next years to maintain and create new canals as well as to allow the operation of the new mobile gates at the three Venice lagoon inlets. Our data reveal important transcriptional and microbial changes of Manila clams after exposure to sediments, therefore reuse of dredged sediments represents a potential risk for the conservation of this species and possibly for other organisms inhabiting the Venice lagoon.
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Affiliation(s)
- Ilaria Bernardini
- Department of Comparative Biomedicine and Food Science, University of Padova, Viale Dell'Università 16, Agripolis, 35020, Legnaro, PD, Italy
| | - Andrea Quagliariello
- Department of Comparative Biomedicine and Food Science, University of Padova, Viale Dell'Università 16, Agripolis, 35020, Legnaro, PD, Italy
| | - Luca Peruzza
- Department of Comparative Biomedicine and Food Science, University of Padova, Viale Dell'Università 16, Agripolis, 35020, Legnaro, PD, Italy
| | - Maria Elena Martino
- Department of Comparative Biomedicine and Food Science, University of Padova, Viale Dell'Università 16, Agripolis, 35020, Legnaro, PD, Italy
| | - Giulia Dalla Rovere
- Department of Comparative Biomedicine and Food Science, University of Padova, Viale Dell'Università 16, Agripolis, 35020, Legnaro, PD, Italy
| | - Silvia Iori
- Department of Comparative Biomedicine and Food Science, University of Padova, Viale Dell'Università 16, Agripolis, 35020, Legnaro, PD, Italy
| | - Davide Asnicar
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35131, Padua, Italy
- Aquatic Bioscience, Huntsman Marine Science Centre, 1 Lower Campus Road, E5B 2L7, St Andrews, New Brunswick, Canada
| | - Maria Ciscato
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35131, Padua, Italy
| | - Jacopo Fabrello
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35131, Padua, Italy
| | - Fabiana Corami
- Department of Environmental Sciences, Informatics, and Statistics, Ca' Foscari University of Venice, Via Torino, 155, 30172, Venice-Mestre, Italy
- Institute of Polar Sciences, CNR-ISP, Foscari University of Venice, Campus Scientifico - CaVia Torino, 155, 30172, Venice-Mestre, Italy
| | - Martina Cecchetto
- Department of Environmental Sciences, Informatics, and Statistics, Ca' Foscari University of Venice, Via Torino, 155, 30172, Venice-Mestre, Italy
| | - Elisa Giubilato
- Department of Environmental Sciences, Informatics, and Statistics, Ca' Foscari University of Venice, Via Torino, 155, 30172, Venice-Mestre, Italy
| | - Claudio Carrer
- Thetis S.P.a. C/o laboratorio del Provveditorato Interregionale Alle Opere Pubbliche Per Il Veneto, Il Trentino Alto Adige E Il Friuli Venezia Giulia, Venice-Mestre, Italy
| | - Cinzia Bettiol
- Department of Environmental Sciences, Informatics, and Statistics, Ca' Foscari University of Venice, Via Torino, 155, 30172, Venice-Mestre, Italy
| | - Elena Semenzin
- Department of Environmental Sciences, Informatics, and Statistics, Ca' Foscari University of Venice, Via Torino, 155, 30172, Venice-Mestre, Italy
| | - Antonio Marcomini
- Department of Environmental Sciences, Informatics, and Statistics, Ca' Foscari University of Venice, Via Torino, 155, 30172, Venice-Mestre, Italy
| | - Valerio Matozzo
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35131, Padua, Italy
| | - Luca Bargelloni
- Department of Comparative Biomedicine and Food Science, University of Padova, Viale Dell'Università 16, Agripolis, 35020, Legnaro, PD, Italy
| | - Massimo Milan
- Department of Comparative Biomedicine and Food Science, University of Padova, Viale Dell'Università 16, Agripolis, 35020, Legnaro, PD, Italy.
- NFBC, National Future Biodiversity Center, Palermo, Italy.
| | - Tomaso Patarnello
- Department of Comparative Biomedicine and Food Science, University of Padova, Viale Dell'Università 16, Agripolis, 35020, Legnaro, PD, Italy
- NFBC, National Future Biodiversity Center, Palermo, Italy
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Jeong MH, Urquhart G, Lewis C, Chi Z, Jewell JL. Inhibition of phosphodiesterase 4D suppresses mTORC1 signaling and pancreatic cancer growth. JCI Insight 2023; 8:e158098. [PMID: 37427586 PMCID: PMC10371348 DOI: 10.1172/jci.insight.158098] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 05/23/2023] [Indexed: 07/11/2023] Open
Abstract
The mammalian target of rapamycin complex 1 (mTORC1) senses multiple upstream stimuli to orchestrate anabolic and catabolic events that regulate cell growth and metabolism. Hyperactivation of mTORC1 signaling is observed in multiple human diseases; thus, pathways that suppress mTORC1 signaling may help to identify new therapeutic targets. Here, we report that phosphodiesterase 4D (PDE4D) promotes pancreatic cancer tumor growth by increasing mTORC1 signaling. GPCRs paired to Gαs proteins activate adenylyl cyclase, which in turn elevates levels of 3',5'-cyclic adenosine monophosphate (cAMP), whereas PDEs catalyze the hydrolysis of cAMP to 5'-AMP. PDE4D forms a complex with mTORC1 and is required for mTORC1 lysosomal localization and activation. Inhibition of PDE4D and the elevation of cAMP levels block mTORC1 signaling via Raptor phosphorylation. Moreover, pancreatic cancer exhibits an upregulation of PDE4D expression, and high PDE4D levels predict the poor overall survival of patients with pancreatic cancer. Importantly, FDA-approved PDE4 inhibitors repress pancreatic cancer cell tumor growth in vivo by suppressing mTORC1 signaling. Our results identify PDE4D as an important activator of mTORC1 and suggest that targeting PDE4 with FDA-approved inhibitors may be beneficial for the treatment of human diseases with hyperactivated mTORC1 signaling.
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Affiliation(s)
- Mi-Hyeon Jeong
- Department of Molecular Biology
- Harold C. Simmons Comprehensive Cancer Center
- Hamon Center for Regenerative Science and Medicine, and
| | - Greg Urquhart
- Department of Molecular Biology
- Harold C. Simmons Comprehensive Cancer Center
- Hamon Center for Regenerative Science and Medicine, and
| | | | - Zhikai Chi
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Jenna L. Jewell
- Department of Molecular Biology
- Harold C. Simmons Comprehensive Cancer Center
- Hamon Center for Regenerative Science and Medicine, and
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5
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Hu J, Baydyuk M, Huang JK. Impact of amino acids on microglial activation and CNS remyelination. Curr Opin Pharmacol 2022; 66:102287. [PMID: 36067684 DOI: 10.1016/j.coph.2022.102287] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 07/20/2022] [Accepted: 08/01/2022] [Indexed: 11/27/2022]
Abstract
Amino acids and their derivatives function as building blocks as well as signaling molecules to modulate various cellular processes in living organisms. In mice, amino acids accumulate in demyelinated lesions and return to basal levels during remyelination. Studies have found that amino acids and their metabolites modulate immune activity in the central nervous system (CNS) and influence oligodendrocyte differentiation and remyelination efficiency. In this review, we discuss current studies on amino acid metabolism in the context of CNS remyelination. By understanding the mechanisms of amino acid signaling and metabolism in demyelinated lesions, we may deepen our understanding of compartmentalized CNS inflammation in demyelinating disease like multiple sclerosis (MS) and provide evidence to develop novel pharmacological therapies targeting amino acid metabolism to prevent disease worsening.
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Affiliation(s)
- Jingwen Hu
- Department of Biology, Georgetown University, 37th and O St., NW, Washington, DC, 20057, USA
| | - Maryna Baydyuk
- Department of Biology, Georgetown University, 37th and O St., NW, Washington, DC, 20057, USA; Center for Cell Reprogramming, Georgetown University Medical Center, 37th and O St., NW, Washington, DC, 20057, USA
| | - Jeffrey K Huang
- Department of Biology, Georgetown University, 37th and O St., NW, Washington, DC, 20057, USA; Center for Cell Reprogramming, Georgetown University Medical Center, 37th and O St., NW, Washington, DC, 20057, USA.
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6
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Huan J, Grivas P, Birch J, Hansel DE. Emerging Roles for Mammalian Target of Rapamycin (mTOR) Complexes in Bladder Cancer Progression and Therapy. Cancers (Basel) 2022; 14:1555. [PMID: 35326708 PMCID: PMC8946148 DOI: 10.3390/cancers14061555] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 03/03/2022] [Accepted: 03/15/2022] [Indexed: 12/15/2022] Open
Abstract
The mammalian target of rapamycin (mTOR) pathway regulates important cellular functions. Aberrant activation of this pathway, either through upstream activation by growth factors, loss of inhibitory controls, or molecular alterations, can enhance cancer growth and progression. Bladder cancer shows high levels of mTOR activity in approximately 70% of urothelial carcinomas, suggesting a key role for this pathway in this cancer. mTOR signaling initiates through upstream activation of phosphatidylinositol 3 kinase (PI3K) and protein kinase B (AKT) and results in activation of either mTOR complex 1 (mTORC1) or mTOR complex 2 (mTORC2). While these complexes share several key protein components, unique differences in their complex composition dramatically alter the function and downstream cellular targets of mTOR activity. While significant work has gone into analysis of molecular alterations of the mTOR pathway in bladder cancer, this has not yielded significant benefit in mTOR-targeted therapy approaches in urothelial carcinoma to date. New discoveries regarding signaling convergence onto mTOR complexes in bladder cancer could yield unique insights the biology and targeting of this aggressive disease. In this review, we highlight the functional significance of mTOR signaling in urothelial carcinoma and its potential impact on future therapy implications.
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Affiliation(s)
- Jianya Huan
- Department of Pathology & Laboratory Medicine, Oregon Health & Science University, Portland, OR 97239, USA; (J.H.); (J.B.)
| | - Petros Grivas
- Division of Medical Oncology, Department of Medicine, University of Washington School of Medicine, Fred Hutchinson Cancer Research Center, Seattle Cancer Care Alliance, Seattle, WA 98195, USA;
| | - Jasmine Birch
- Department of Pathology & Laboratory Medicine, Oregon Health & Science University, Portland, OR 97239, USA; (J.H.); (J.B.)
| | - Donna E. Hansel
- Department of Pathology & Laboratory Medicine, Oregon Health & Science University, Portland, OR 97239, USA; (J.H.); (J.B.)
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7
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Mafi S, Mansoori B, Taeb S, Sadeghi H, Abbasi R, Cho WC, Rostamzadeh D. mTOR-Mediated Regulation of Immune Responses in Cancer and Tumor Microenvironment. Front Immunol 2022; 12:774103. [PMID: 35250965 PMCID: PMC8894239 DOI: 10.3389/fimmu.2021.774103] [Citation(s) in RCA: 55] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Accepted: 12/14/2021] [Indexed: 12/17/2022] Open
Abstract
The mechanistic/mammalian target of rapamycin (mTOR) is a downstream mediator in the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways, which plays a pivotal role in regulating numerous cellular functions including cell growth, proliferation, survival, and metabolism by integrating a variety of extracellular and intracellular signals in the tumor microenvironment (TME). Dysregulation of the mTOR pathway is frequently reported in many types of human tumors, and targeting the PI3K/Akt/mTOR signaling pathway has been considered an attractive potential therapeutic target in cancer. The PI3K/Akt/mTOR signaling transduction pathway is important not only in the development and progression of cancers but also for its critical regulatory role in the tumor microenvironment. Immunologically, mTOR is emerging as a key regulator of immune responses. The mTOR signaling pathway plays an essential regulatory role in the differentiation and function of both innate and adaptive immune cells. Considering the central role of mTOR in metabolic and translational reprogramming, it can affect tumor-associated immune cells to undergo phenotypic and functional reprogramming in TME. The mTOR-mediated inflammatory response can also promote the recruitment of immune cells to TME, resulting in exerting the anti-tumor functions or promoting cancer cell growth, progression, and metastasis. Thus, deregulated mTOR signaling in cancer can modulate the TME, thereby affecting the tumor immune microenvironment. Here, we review the current knowledge regarding the crucial role of the PI3K/Akt/mTOR pathway in controlling and shaping the immune responses in TME.
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Affiliation(s)
- Sahar Mafi
- Department of Clinical Biochemistry, Yasuj University of Medical Sciences, Yasuj, Iran
- Medicinal Plants Research Center, Yasuj University of Medical Sciences, Yasuj, Iran
| | - Behzad Mansoori
- The Wistar Institute, Molecular & Cellular Oncogenesis Program, Philadelphia, PA, United States
| | - Shahram Taeb
- Department of Radiology, School of Paramedical Sciences, Guilan University of Medical Sciences, Rasht, Iran
- Medical Biotechnology Research Center, School of Paramedical Sciences, Guilan University of Medical Sciences, Rasht, Iran
| | - Hossein Sadeghi
- Medicinal Plants Research Center, Yasuj University of Medical Sciences, Yasuj, Iran
| | - Reza Abbasi
- Medicinal Plants Research Center, Yasuj University of Medical Sciences, Yasuj, Iran
| | - William C. Cho
- Department of Clinical Oncology, Queen Elizabeth Hospital, Hong Kong, Hong Kong SAR, China
- *Correspondence: Davoud Rostamzadeh, ; ; William C. Cho, ;
| | - Davoud Rostamzadeh
- Department of Clinical Biochemistry, Yasuj University of Medical Sciences, Yasuj, Iran
- Medicinal Plants Research Center, Yasuj University of Medical Sciences, Yasuj, Iran
- *Correspondence: Davoud Rostamzadeh, ; ; William C. Cho, ;
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8
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Tooley AS, Kazyken D, Bodur C, Gonzalez IE, Fingar DC. The innate immune kinase TBK1 directly increases mTORC2 activity and downstream signaling to Akt. J Biol Chem 2021; 297:100942. [PMID: 34245780 PMCID: PMC8342794 DOI: 10.1016/j.jbc.2021.100942] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 06/21/2021] [Accepted: 07/06/2021] [Indexed: 02/06/2023] Open
Abstract
TBK1 responds to microbes to initiate cellular responses critical for host innate immune defense. We found previously that TBK1 phosphorylates mTOR (mechanistic target of rapamycin) on S2159 to increase mTOR complex 1 (mTORC1) signaling in response to the growth factor EGF and the viral dsRNA mimetic poly(I:C). mTORC1 and the less well studied mTORC2 respond to diverse cues to control cellular metabolism, proliferation, and survival. Although TBK1 has been linked to Akt phosphorylation, a direct relationship between TBK1 and mTORC2, an Akt kinase, has not been described. By studying MEFs lacking TBK1, as well as MEFs, macrophages, and mice bearing an Mtor S2159A knock-in allele (MtorA/A) using in vitro kinase assays and cell-based approaches, we demonstrate here that TBK1 activates mTOR complex 2 (mTORC2) directly to increase Akt phosphorylation. We find that TBK1 and mTOR S2159 phosphorylation promotes mTOR-dependent phosphorylation of Akt in response to several growth factors and poly(I:C). Mechanistically, TBK1 coimmunoprecipitates with mTORC2 and phosphorylates mTOR S2159 within mTORC2 in cells. Kinase assays demonstrate that TBK1 and mTOR S2159 phosphorylation increase mTORC2 intrinsic catalytic activity. Growth factors failed to activate TBK1 or increase mTOR S2159 phosphorylation in MEFs. Thus, basal TBK1 activity cooperates with growth factors in parallel to increase mTORC2 (and mTORC1) signaling. Collectively, these results reveal cross talk between TBK1 and mTOR, key regulatory nodes within two major signaling networks. As TBK1 and mTOR contribute to tumorigenesis and metabolic disorders, these kinases may work together in a direct manner in a variety of physiological and pathological settings.
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Affiliation(s)
- Aaron Seth Tooley
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Dubek Kazyken
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Cagri Bodur
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Ian E Gonzalez
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Diane C Fingar
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan, USA.
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9
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Nazari N, Jafari F, Ghalamfarsa G, Hadinia A, Atapour A, Ahmadi M, Dolati S, Rostamzadeh D. The emerging role of microRNA in regulating the mTOR signaling pathway in immune and inflammatory responses. Immunol Cell Biol 2021; 99:814-832. [PMID: 33988889 DOI: 10.1111/imcb.12477] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 05/10/2021] [Accepted: 05/10/2021] [Indexed: 01/01/2023]
Abstract
The mechanistic/mammalian target of rapamycin (mTOR) is considered to be an atypical protein kinase that plays a critical role in integrating different cellular and environmental inputs in the form of growth factors, nutrients and energy and, subsequently, in regulating different cellular events, including cell metabolism, survival, homeostasis, growth and cellular differentiation. Immunologically, mTOR is a critical regulator of immune function through integrating numerous signals from the immune microenvironment, which coordinates the functions of immune cells and T cell fate decisions. The crucial role of mTOR in immune responses has been lately even more appreciated. MicroRNAs (miRNAs) are endogenous, small, noncoding single-stranded RNAs that act as molecular regulators involved in multiple processes during immune cells development, homeostasis, activation and effector polarization. Several studies have recently indicated that a range of miRNAs are involved in regulating the phosphoinositide 3-kinase/protein kinase B/mTOR (PI3K/AKT/mTOR) signaling pathway by targeting multiple components of this signaling pathway and modulating the expression and function of these targets. Current evidence has revealed the interplay between miRNAs and the mTOR pathway circuits in various immune cell types. The expression of individual miRNA can affect the function of mTOR signaling to determine the cell fate decisions in immune responses through coordinating immune signaling and cell metabolism. Dysregulation of the mTOR pathway/miRNAs crosstalk has been reported in cancers and various immune-related diseases. Thus, expression profiles of dysregulated miRNAs could influence the mTOR pathway, resulting in the promotion of aberrant immunity. This review summarizes the latest information regarding the reciprocal role of the mTOR signaling pathway and miRNAs in orchestrating immune responses.
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Affiliation(s)
- Nazanin Nazari
- Shiraz Institute for Cancer Research, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Farzaneh Jafari
- Department of Medical Genetics, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Ghasem Ghalamfarsa
- Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran
| | - Abolghasem Hadinia
- Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran
| | - Amir Atapour
- Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Majid Ahmadi
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Sanam Dolati
- Physical Medicine and Rehabilitation Research Center, Aging Research Institute, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Davood Rostamzadeh
- Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran.,Medicinal Plants Research Center, Yasuj University of Medical Sciences, Yasuj, Iran
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10
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Meng D, Yang Q, Melick CH, Park BC, Hsieh T, Curukovic A, Jeong M, Zhang J, James NG, Jewell JL. ArfGAP1 inhibits mTORC1 lysosomal localization and activation. EMBO J 2021; 40:e106412. [PMID: 33988249 PMCID: PMC8204869 DOI: 10.15252/embj.2020106412] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 03/14/2021] [Accepted: 03/24/2021] [Indexed: 12/11/2022] Open
Abstract
The mammalian target of rapamycin complex 1 (mTORC1) integrates nutrients, growth factors, stress, and energy status to regulate cell growth and metabolism. Amino acids promote mTORC1 lysosomal localization and subsequent activation. However, the subcellular location or interacting proteins of mTORC1 under amino acid-deficient conditions is not completely understood. Here, we identify ADP-ribosylation factor GTPase-activating protein 1 (ArfGAP1) as a crucial regulator of mTORC1. ArfGAP1 interacts with mTORC1 in the absence of amino acids and inhibits mTORC1 lysosomal localization and activation. Mechanistically, the membrane curvature-sensing amphipathic lipid packing sensor (ALPS) motifs that bind to vesicle membranes are crucial for ArfGAP1 to interact with and regulate mTORC1 activity. Importantly, ArfGAP1 represses cell growth through mTORC1 and is an independent prognostic factor for the overall survival of pancreatic cancer patients. Our study identifies ArfGAP1 as a critical regulator of mTORC1 that functions by preventing the lysosomal transport and activation of mTORC1, with potential for cancer therapeutics.
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Affiliation(s)
- Delong Meng
- Department of Molecular BiologyUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Harold C. Simmons Comprehensive Cancer CenterUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Hamon Center for Regenerative Science and MedicineUniversity of Texas Southwestern Medical CenterDallasTXUSA
| | - Qianmei Yang
- Department of Molecular BiologyUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Harold C. Simmons Comprehensive Cancer CenterUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Hamon Center for Regenerative Science and MedicineUniversity of Texas Southwestern Medical CenterDallasTXUSA
| | - Chase H Melick
- Department of Molecular BiologyUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Harold C. Simmons Comprehensive Cancer CenterUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Hamon Center for Regenerative Science and MedicineUniversity of Texas Southwestern Medical CenterDallasTXUSA
| | - Brenden C Park
- Department of Molecular BiologyUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Harold C. Simmons Comprehensive Cancer CenterUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Hamon Center for Regenerative Science and MedicineUniversity of Texas Southwestern Medical CenterDallasTXUSA
| | - Ting‐Sung Hsieh
- Department of Molecular BiologyUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Harold C. Simmons Comprehensive Cancer CenterUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Hamon Center for Regenerative Science and MedicineUniversity of Texas Southwestern Medical CenterDallasTXUSA
| | - Adna Curukovic
- Department of Molecular BiologyUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Harold C. Simmons Comprehensive Cancer CenterUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Hamon Center for Regenerative Science and MedicineUniversity of Texas Southwestern Medical CenterDallasTXUSA
| | - Mi‐Hyeon Jeong
- Department of Molecular BiologyUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Harold C. Simmons Comprehensive Cancer CenterUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Hamon Center for Regenerative Science and MedicineUniversity of Texas Southwestern Medical CenterDallasTXUSA
| | - Junmei Zhang
- Department of Molecular BiologyUniversity of Texas Southwestern Medical CenterDallasTXUSA
| | - Nicholas G James
- Department of Cell and Molecular BiologyJohn A. Burns School of MedicineUniversity of HawaiiHonoluluHIUSA
| | - Jenna L Jewell
- Department of Molecular BiologyUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Harold C. Simmons Comprehensive Cancer CenterUniversity of Texas Southwestern Medical CenterDallasTXUSA
- Hamon Center for Regenerative Science and MedicineUniversity of Texas Southwestern Medical CenterDallasTXUSA
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11
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Abstract
This review provides epidemiological and translational evidence for milk and dairy intake as critical risk factors in the pathogenesis of hepatocellular carcinoma (HCC). Large epidemiological studies in the United States and Europe identified total dairy, milk and butter intake with the exception of yogurt as independent risk factors of HCC. Enhanced activity of mechanistic target of rapamycin complex 1 (mTORC1) is a hallmark of HCC promoted by hepatitis B virus (HBV) and hepatitis C virus (HCV). mTORC1 is also activated by milk protein-induced synthesis of hepatic insulin-like growth factor 1 (IGF-1) and branched-chain amino acids (BCAAs), abundant constituents of milk proteins. Over the last decades, annual milk protein-derived BCAA intake increased 3 to 5 times in Western countries. In synergy with HBV- and HCV-induced secretion of hepatocyte-derived exosomes enriched in microRNA-21 (miR-21) and miR-155, exosomes of pasteurized milk as well deliver these oncogenic miRs to the human liver. Thus, milk exosomes operate in a comparable fashion to HBV- or HCV- induced exosomes. Milk-derived miRs synergistically enhance IGF-1-AKT-mTORC1 signaling and promote mTORC1-dependent translation, a meaningful mechanism during the postnatal growth phase, but a long-term adverse effect promoting the development of HCC. Both, dietary BCAA abundance combined with oncogenic milk exosome exposure persistently overstimulate hepatic mTORC1. Chronic alcohol consumption as well as type 2 diabetes mellitus (T2DM), two HCC-related conditions, increase BCAA plasma levels. In HCC, mTORC1 is further hyperactivated due to RAB1 mutations as well as impaired hepatic BCAA catabolism, a metabolic hallmark of T2DM. The potential HCC-preventive effect of yogurt may be caused by lactobacilli-mediated degradation of BCAAs, inhibition of branched-chain α-ketoacid dehydrogenase kinase via production of intestinal medium-chain fatty acids as well as degradation of milk exosomes including their oncogenic miRs. A restriction of total animal protein intake realized by a vegetable-based diet is recommended for the prevention of HCC.
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Affiliation(s)
- Bodo C Melnik
- Department of Dermatology, Environmental Medicine and Health Theory, University of Osnabrück, Osnabrück, Germany
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12
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King KE, Losier TT, Russell RC. Regulation of Autophagy Enzymes by Nutrient Signaling. Trends Biochem Sci 2021; 46:687-700. [PMID: 33593593 DOI: 10.1016/j.tibs.2021.01.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 01/12/2021] [Accepted: 01/21/2021] [Indexed: 02/07/2023]
Abstract
Autophagy is the primary catabolic program of the cell that promotes survival in response to metabolic stress. It is tightly regulated by a suite of kinases responsive to nutrient status, including mammalian target of rapamycin complex 1 (mTORC1), AMP-activated protein kinase (AMPK), protein kinase C-α (PKCα), MAPK-activated protein kinases 2/3 (MAPKAPK2/3), Rho kinase 1 (ROCK1), c-Jun N-terminal kinase 1 (JNK), and Casein kinase 2 (CSNK2). Here, we highlight recently uncovered mechanisms linking amino acid, glucose, and oxygen levels to autophagy regulation through mTORC1 and AMPK. In addition, we describe new pathways governing the autophagic machinery, including the Unc-51-like (ULK1), vacuolar protein sorting 34 (VPS34), and autophagy related 16 like 1 (ATG16L1) enzyme complexes. Novel downstream targets of ULK1 protein kinase are also discussed, such as the ATG16L1 subunit of the microtubule-associated protein 1 light chain 3 (LC3)-lipidating enzyme and the ATG14 subunit of the VPS34 complex. Collectively, we describe the complexities of the autophagy pathway and its role in maintaining cellular nutrient homeostasis during times of starvation.
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Affiliation(s)
- Karyn E King
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ONT, Canada
| | - Truc T Losier
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ONT, Canada
| | - Ryan C Russell
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ONT, Canada; Center for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, ONT, Canada; Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ONT, Canada.
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13
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Sakamoto H, Yamasaki T, Sumiyoshi T, Takeda M, Shibasaki N, Utsunomiya N, Arakaki R, Akamatsu S, Kobayashi T, Inoue T, Kamba T, Nakamura E, Ogawa O. Functional and genomic characterization of patient-derived xenograft model to study the adaptation to mTORC1 inhibitor in clear cell renal cell carcinoma. Cancer Med 2021; 10:119-134. [PMID: 33107222 PMCID: PMC7826464 DOI: 10.1002/cam4.3578] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 09/24/2020] [Accepted: 10/12/2020] [Indexed: 02/06/2023] Open
Abstract
Resistance to the mechanistic target of rapamycin (mTOR) inhibitors, which are a standard treatment for advanced clear cell renal cell carcinoma (ccRCC), eventually develops in most cases. In this study, we established a patient-derived xenograft (PDX) model which acquired resistance to the mTOR inhibitor temsirolimus, and explored the underlying mechanisms of resistance acquisition. Temsirolimus was administered to PDX model mice, and one cohort of PDX models acquired resistance after repeated passages. PDX tumors were genetically analyzed by whole-exome sequencing and detected several genetic alterations specific to resistant tumors. Among them, mutations in ANKRD12 and DNMT1 were already identified in the early passage of a resistant PDX model, and we focused on a DNMT1 mutation as a potential candidate for developing the resistant phenotype. While DNMT1 expression in temsirolimus-resistant tumors was comparable with the control tumors, DNMT enzyme activity was decreased in resistant tumors compared with controls. Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9-mediated heterozygous knockdown of DNMT1 in the temsirolimus-sensitive ccRCC (786-O) cell line was shown to result in a temsirolimus-resistant phenotype in vitro and in vivo. Integrated gene profiles using methylation and microarray analyses of PDX tumors suggested a global shift for the hypomethylation status including promotor regions, and showed the upregulation of several molecules that regulate the mTOR pathway in temsirolimus-resistant tumors. Present study showed the feasibility of PDX model to explore the mechanisms of mTOR resistance acquisition and suggested that genetic alterations, including that of DNMT1, which alter the methylation status in cancer cells, are one of the potential mechanisms of developing resistance to temsirolimus.
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Affiliation(s)
- Hiromasa Sakamoto
- Department of UrologyKyoto University Graduate School of MedicineKyotoJapan
| | - Toshinari Yamasaki
- Department of UrologyKyoto University Graduate School of MedicineKyotoJapan
| | - Takayuki Sumiyoshi
- Department of UrologyKyoto University Graduate School of MedicineKyotoJapan
| | - Masashi Takeda
- Department of UrologyKyoto University Graduate School of MedicineKyotoJapan
| | - Noboru Shibasaki
- Department of UrologyKyoto University Graduate School of MedicineKyotoJapan
| | - Noriaki Utsunomiya
- Department of UrologyKyoto University Graduate School of MedicineKyotoJapan
| | - Ryuichiro Arakaki
- Department of UrologyKyoto University Graduate School of MedicineKyotoJapan
| | - Shusuke Akamatsu
- Department of UrologyKyoto University Graduate School of MedicineKyotoJapan
| | - Takashi Kobayashi
- Department of UrologyKyoto University Graduate School of MedicineKyotoJapan
| | - Takahiro Inoue
- Department of Nephro‐Urologic Surgery and AndrologyMie University Graduate School of MedicineTsuJapan
| | - Tomomi Kamba
- Department of UrologyKumamoto University Graduate School of Medical SciencesKumamotoJapan
| | - Eijiro Nakamura
- DSK Project, Medical Innovation CenterKyoto University Graduate School of MedicineKyotoJapan
| | - Osamu Ogawa
- Department of UrologyKyoto University Graduate School of MedicineKyotoJapan
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14
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Nada S, Okada M. Genetic dissection of Ragulator structure and function in amino acid-dependent regulation of mTORC1. J Biochem 2020; 168:621-632. [PMID: 32653916 DOI: 10.1093/jb/mvaa076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 06/30/2020] [Indexed: 11/12/2022] Open
Abstract
Ragulator is a heteropentameric protein complex consisting of two roadblock heterodimers wrapped by the membrane anchor p18/Lamtor1. The Ragulator complex functions as a lysosomal membrane scaffold for Rag GTPases to recruit and activate mechanistic target of rapamycin complex 1 (mTORC1). However, the roles of Ragulator structure in the regulation of mTORC1 function remain elusive. In this study, we disrupted Ragulator structure by directly anchoring RagC to lysosomes and monitored the effect on amino acid-dependent mTORC1 activation. Expression of lysosome-anchored RagC in p18-deficient cells resulted in constitutive lysosomal localization and amino acid-independent activation of mTORC1. Co-expression of Ragulator in this system restored the amino acid dependency of mTORC1 activation. Furthermore, ablation of Gator1, a suppressor of Rag GTPases, induced amino acid-independent activation of mTORC1 even in the presence of Ragulator. These results demonstrate that Ragulator structure is essential for amino acid-dependent regulation of Rag GTPases via Gator1. In addition, our genetic analyses revealed new roles of amino acids in the regulation of mTORC1 as follows: amino acids could activate a fraction of mTORC1 in a Rheb-independent manner, and could also drive negative-feedback regulation of mTORC1 signalling via protein phosphatases. These intriguing findings contribute to our overall understanding of the regulatory mechanisms of mTORC1 signalling.
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Affiliation(s)
- Shigeyuki Nada
- Department of Oncogene Research, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565, Japan
| | - Masato Okada
- Department of Oncogene Research, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565, Japan
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15
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Pang W, Hu F. Cellular and physiological functions of C9ORF72 and implications for ALS/FTD. J Neurochem 2020; 157:334-350. [PMID: 33259633 DOI: 10.1111/jnc.15255] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 10/27/2020] [Accepted: 11/26/2020] [Indexed: 12/12/2022]
Abstract
The hexanucleotide repeat expansion (HRE) in the C9ORF72 gene is the main cause of two tightly linked neurodegenerative diseases, amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). HRE leads to not only a gain of toxicity from RNA repeats and dipeptide repeats but also reduced levels of C9ORF72 protein. However, the cellular and physiological functions of C9ORF72 were unknown until recently. Through proteomic analysis, Smith-Magenis chromosome regions 8 (SMCR8) and WD repeat-containing protein (WDR41) were identified as binding partners of C9ORF72. These three proteins have been shown to form a tight complex, but the exact functions of this complex remain to be characterized. Both C9ORF72 and SMCR8 contain a DENN domain, which has been shown to regulate the activities of small GTPases. The C9ORF72 complex has been implicated in many cellular processes, including vesicle trafficking, lysosome homeostasis, mTORC1 signaling , and autophagy. C9ORF72 deficiency in mice results in exaggerated inflammatory responses and human patients with C9ORF72 mutations have neuroinflammation phenotype. Recent studies indicate that C9ORF72 regulates trafficking and lysosomal degradation of inflammatory mediators, including toll-like receptors (TLRs) and STING, to affect inflammatory outputs. Further exploration of cellular and physiological functions of C9ORF72 will help dissect the pathological mechanism of ALS/FTD caused by C9ORF72 mutations.
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Affiliation(s)
- Weilun Pang
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Fenghua Hu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
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16
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de Souza DR, Vasconcelos DAAD, Murata GM, Fortes MAS, Marzuca-Nassr GN, Levada-Pires AC, Vitzel KF, Abreu P, Scervino MVM, Hirabara SM, Curi R, Pithon-Curi TC. Glutamine supplementation versus functional overload in extensor digitorum longus muscle hypertrophy. PHARMANUTRITION 2020. [DOI: 10.1016/j.phanu.2020.100236] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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17
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Jang YG, Choi Y, Jun K, Chung J. Mislocalization of TORC1 to Lysosomes Caused by KIF11 Inhibition Leads to Aberrant TORC1 Activity. Mol Cells 2020; 43:705-717. [PMID: 32759469 PMCID: PMC7468583 DOI: 10.14348/molcells.2020.0089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/15/2020] [Accepted: 06/24/2020] [Indexed: 01/15/2023] Open
Abstract
While the growth factors like insulin initiate a signaling cascade to induce conformational changes in the mechanistic target of rapamycin complex 1 (mTORC1), amino acids cause the complex to localize to the site of activation, the lysosome. The precise mechanism of how mTORC1 moves in and out of the lysosome is yet to be elucidated in detail. Here we report that microtubules and the motor protein KIF11 are required for the proper dissociation of mTORC1 from the lysosome upon amino acid scarcity. When microtubules are disrupted or KIF11 is knocked down, we observe that mTORC1 localizes to the lysosome even in the amino acid-starved situation where it should be dispersed in the cytosol, causing an elevated mTORC1 activity. Moreover, in the mechanistic perspective, we discover that mTORC1 interacts with KIF11 on the motor domain of KIF11, enabling the complex to move out of the lysosome along microtubules. Our results suggest not only a novel way of the regulation regarding amino acid availability for mTORC1, but also a new role of KIF11 and microtubules in mTOR signaling.
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Affiliation(s)
- Yoon-Gu Jang
- Institute of Molecular Biology and Genetics, Seoul National University, Seoul 08826, Korea
- School of Biological Sciences, Seoul National University, Seoul 0886, Korea
- These authors contributed equally to this work.
| | - Yujin Choi
- Institute of Molecular Biology and Genetics, Seoul National University, Seoul 08826, Korea
- School of Biological Sciences, Seoul National University, Seoul 0886, Korea
- These authors contributed equally to this work.
| | - Kyoungho Jun
- Institute of Molecular Biology and Genetics, Seoul National University, Seoul 08826, Korea
- School of Biological Sciences, Seoul National University, Seoul 0886, Korea
| | - Jongkyeong Chung
- Institute of Molecular Biology and Genetics, Seoul National University, Seoul 08826, Korea
- School of Biological Sciences, Seoul National University, Seoul 0886, Korea
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18
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Shorning BY, Dass MS, Smalley MJ, Pearson HB. The PI3K-AKT-mTOR Pathway and Prostate Cancer: At the Crossroads of AR, MAPK, and WNT Signaling. Int J Mol Sci 2020; 21:E4507. [PMID: 32630372 PMCID: PMC7350257 DOI: 10.3390/ijms21124507] [Citation(s) in RCA: 287] [Impact Index Per Article: 71.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 06/22/2020] [Accepted: 06/22/2020] [Indexed: 12/13/2022] Open
Abstract
Oncogenic activation of the phosphatidylinositol-3-kinase (PI3K), protein kinase B (PKB/AKT), and mammalian target of rapamycin (mTOR) pathway is a frequent event in prostate cancer that facilitates tumor formation, disease progression and therapeutic resistance. Recent discoveries indicate that the complex crosstalk between the PI3K-AKT-mTOR pathway and multiple interacting cell signaling cascades can further promote prostate cancer progression and influence the sensitivity of prostate cancer cells to PI3K-AKT-mTOR-targeted therapies being explored in the clinic, as well as standard treatment approaches such as androgen-deprivation therapy (ADT). However, the full extent of the PI3K-AKT-mTOR signaling network during prostate tumorigenesis, invasive progression and disease recurrence remains to be determined. In this review, we outline the emerging diversity of the genetic alterations that lead to activated PI3K-AKT-mTOR signaling in prostate cancer, and discuss new mechanistic insights into the interplay between the PI3K-AKT-mTOR pathway and several key interacting oncogenic signaling cascades that can cooperate to facilitate prostate cancer growth and drug-resistance, specifically the androgen receptor (AR), mitogen-activated protein kinase (MAPK), and WNT signaling cascades. Ultimately, deepening our understanding of the broader PI3K-AKT-mTOR signaling network is crucial to aid patient stratification for PI3K-AKT-mTOR pathway-directed therapies, and to discover new therapeutic approaches for prostate cancer that improve patient outcome.
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Affiliation(s)
| | | | | | - Helen B. Pearson
- The European Cancer Stem Cell Research Institute, Cardiff University, Hadyn Ellis Building, Maindy Road, Cardiff CF24 4HQ, Wales, UK; (B.Y.S.); (M.S.D.); (M.J.S.)
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19
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Lai GR, Lee YF, Yan SJ, Ting HJ. Active vitamin D induces gene-specific hypomethylation in prostate cancer cells developing vitamin D resistance. Am J Physiol Cell Physiol 2020; 318:C836-C847. [PMID: 32159363 DOI: 10.1152/ajpcell.00522.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Prostate cancer (PCa) is a leading cause of cancer death in men. Despite the antiproliferative effects of 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3] on PCa, accumulating evidence indicates that 1,25(OH)2D3 promotes cancer progression by increasing genome plasticity. Our investigation of epigenetic changes associated with vitamin D insensitivity found that 1,25(OH)2D3 treatment reduced the expression levels and activities of DNA methyltransferases 1 and 3B (DNMT1 and DNMT3B, respectively). In silico analysis and reporter assay confirmed that 1,25(OH)2D3 downregulated transcriptional activation of the DNMT3B promoter and upregulated microRNAs targeting the 3'-untranslated regions of DNMT3B. We then profiled DNA methylation in the vitamin D-resistant PC-3 cells and a resistant PCa cell model generated by long-term 1,25(OH)2D3 exposure. Several candidate genes were found to be hypomethylated and overexpressed in vitamin D-resistant PCa cells compared with vitamin D-sensitive cells. Most of the identified genes were associated with mammalian target of rapamycin (mTOR) signaling activation, which is known to promote cancer progression. Among them, we found that inhibition of ribosomal protein S6 kinase A1 (RPS6KA1) promoted vitamin D sensitivity in PC-3 cells. Furthermore, The Cancer Genome Atlas (TCGA) prostate cancer data set demonstrated that midline 1 (MID1) expression is positively correlated with tumor stage. Overall, our study reveals an inhibitory mechanism of 1,25(OH)2D3 on DNMT3B, which may contribute to vitamin D resistance in PCa.
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Affiliation(s)
- Guan-Rong Lai
- Department of Physiology, College of Medicine, National Cheng Kung University, Tainan, Taiwan, Republic of China
| | - Yi-Fen Lee
- Department of Urology, Pathology, and Wilmot Cancer Cancer, University of Rochester, Rochester, New York
| | - Shian-Jang Yan
- Department of Physiology, College of Medicine, National Cheng Kung University, Tainan, Taiwan, Republic of China
| | - Huei-Ju Ting
- Department of Biological Sciences and Technology, National University of Tainan, Tainan, Taiwan, Republic of China
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20
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Abstract
The mechanistic target of rapamycin complex 1 (mTORC1) controls cell growth and metabolism in response to various environmental inputs, especially amino acids. In fact, the activity of mTORC1 is highly sensitive to changes in amino acid levels. Over past decades, a variety of proteins have been identified as participating in the mTORC1 pathway regulated by amino acids. Classically, the Rag guanosine triphosphatases (GTPases), which reside on the lysosome, transmit amino acid availability to the mTORC1 pathway and recruit mTORC1 to the lysosome upon amino acid sufficiency. Recently, several sensors of leucine, arginine, and S-adenosylmethionine for the amino acid-stimulated mTORC1 pathway have been coming to light. Characterization of these sensors is requisite for understanding how cells adjust amino acid sensing pathways to their different needs. In this review, we summarize recent advances in amino acid sensing mechanisms that regulate mTORC1 activity and highlight these identified sensors that accurately transmit specific amino acid signals to the mTORC1 pathway.
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Affiliation(s)
- Xiu-Zhi Li
- State Key Laboratory of Agricultural Microbiology, College of Animal Sciences and Technology, Huazhong Agricultural University, Wuhan 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China.,Hubei Provincial Engineering Laboratory for Pig Precision Feeding and Feed Safety Technology, Wuhan 430070, China
| | - Xiang-Hua Yan
- State Key Laboratory of Agricultural Microbiology, College of Animal Sciences and Technology, Huazhong Agricultural University, Wuhan 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China.,Hubei Provincial Engineering Laboratory for Pig Precision Feeding and Feed Safety Technology, Wuhan 430070, China
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21
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Zhao D, Wu J, Zhao Y, Shao W, Cheng Q, Shao X, Yuan X, Ye J, Gao J, Jin M, Li C, Chen X, Zhao Y, Xue B. Zoledronic acid inhibits TSC2-null cell tumor growth via RhoA/YAP signaling pathway in mouse models of lymphangioleiomyomatosis. Cancer Cell Int 2020; 20:46. [PMID: 32063747 PMCID: PMC7011352 DOI: 10.1186/s12935-020-1131-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 01/29/2020] [Indexed: 12/14/2022] Open
Abstract
Background This study is to investigate the effects of zoledronic acid (ZA) on TSC2-null cell proliferation and on the tumor progression and recurrence in mouse models of lymphangioleiomyomatosis (LAM). Methods Subcutaneous mouse models and LAM mouse models were established. Immunohistochemistry and immunofluorescence were performed to detect the protein expression levels. TUNEL assay was conducted to detect cell apoptosis. Immunoprecipitation was carried out to determine the interaction between proteins. Results ZA prevented the growth of TSC2-null cells both in culture and in LAM mouse models. Compared with rapamycin, ZA more effectively promoted the apoptosis of TSC2-null cells. Moreover, combined with the rapamycin, ZA effectively suppressed the tumor recurrence after drug withdrawal and ZA inhibited the activity of GTPase RhoA by decreasing protein geranylgeranylation, resulting in changes of Yap nucleus translocation. Conclusion ZA promotes cell apoptosis in TSC2-null cells through the RhoA/YAP signaling pathway. ZA may be used for the clinical treatment of LAM.
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Affiliation(s)
- Dandan Zhao
- 2State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Key Laboratory of Molecular Medicine and School of Medicine, Nanjing University, Nanjing, 210093 Jiangsu China
| | - Jing Wu
- 1Core Laboratory, Sir Run Run Hospital, Nanjing Medical University, Nanjing, 211166 Jiangsu China
| | - Yinjuan Zhao
- 3Collaborative Innovation Center of Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, 210037 Jiangsu China
| | - Wei Shao
- 1Core Laboratory, Sir Run Run Hospital, Nanjing Medical University, Nanjing, 211166 Jiangsu China
| | - Qi Cheng
- 2State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Key Laboratory of Molecular Medicine and School of Medicine, Nanjing University, Nanjing, 210093 Jiangsu China
| | - Xiaoyan Shao
- 2State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Key Laboratory of Molecular Medicine and School of Medicine, Nanjing University, Nanjing, 210093 Jiangsu China
| | - Xianwen Yuan
- 2State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Key Laboratory of Molecular Medicine and School of Medicine, Nanjing University, Nanjing, 210093 Jiangsu China.,4Department of Hepatobiliary Surgery, The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008 Jiangsu China
| | - Juan Ye
- 2State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Key Laboratory of Molecular Medicine and School of Medicine, Nanjing University, Nanjing, 210093 Jiangsu China.,5Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, 210028 Jiangsu China
| | - Jianpu Gao
- 1Core Laboratory, Sir Run Run Hospital, Nanjing Medical University, Nanjing, 211166 Jiangsu China
| | - Meiling Jin
- 6Pulmonary Department, Zhongshan Hospital, Fudan University, Shanghai, 200032 China
| | - Chaojun Li
- 2State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Key Laboratory of Molecular Medicine and School of Medicine, Nanjing University, Nanjing, 210093 Jiangsu China.,7Jiangsu Key Laboratory of Molecular Medicine and School of Medicine, Nanjing University, Nanjing, 210093 Jiangsu China
| | - Xiaolin Chen
- 9Respiratory Department, Sir Run Run Hospital, Nanjing Medical University, Nanjing, 211166 Jiangsu China
| | - Yue Zhao
- 2State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Key Laboratory of Molecular Medicine and School of Medicine, Nanjing University, Nanjing, 210093 Jiangsu China.,7Jiangsu Key Laboratory of Molecular Medicine and School of Medicine, Nanjing University, Nanjing, 210093 Jiangsu China
| | - Bin Xue
- 1Core Laboratory, Sir Run Run Hospital, Nanjing Medical University, Nanjing, 211166 Jiangsu China.,2State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Key Laboratory of Molecular Medicine and School of Medicine, Nanjing University, Nanjing, 210093 Jiangsu China.,7Jiangsu Key Laboratory of Molecular Medicine and School of Medicine, Nanjing University, Nanjing, 210093 Jiangsu China.,8State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009 Jiangsu China
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22
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Samuel SM, Varghese E, Kubatka P, Triggle CR, Büsselberg D. Metformin: The Answer to Cancer in a Flower? Current Knowledge and Future Prospects of Metformin as an Anti-Cancer Agent in Breast Cancer. Biomolecules 2019; 9:E846. [PMID: 31835318 PMCID: PMC6995629 DOI: 10.3390/biom9120846] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 12/02/2019] [Accepted: 12/06/2019] [Indexed: 12/25/2022] Open
Abstract
Interest has grown in studying the possible use of well-known anti-diabetic drugs as anti-cancer agents individually or in combination with, frequently used, chemotherapeutic agents and/or radiation, owing to the fact that diabetes heightens the risk, incidence, and rapid progression of cancers, including breast cancer, in an individual. In this regard, metformin (1, 1-dimethylbiguanide), well known as 'Glucophage' among diabetics, was reported to be cancer preventive while also being a potent anti-proliferative and anti-cancer agent. While meta-analysis studies reported a lower risk and incidence of breast cancer among diabetic individuals on a metformin treatment regimen, several in vitro, pre-clinical, and clinical studies reported the efficacy of using metformin individually as an anti-cancer/anti-tumor agent or in combination with chemotherapeutic drugs or radiation in the treatment of different forms of breast cancer. However, unanswered questions remain with regards to areas such as cancer treatment specific therapeutic dosing of metformin, specificity to cancer cells at high concentrations, resistance to metformin therapy, efficacy of combinatory therapeutic approaches, post-therapeutic relapse of the disease, and efficacy in cancer prevention in non-diabetic individuals. In the current article, we discuss the biology of metformin and its molecular mechanism of action, the existing cellular, pre-clinical, and clinical studies that have tested the anti-tumor potential of metformin as a potential anti-cancer/anti-tumor agent in breast cancer therapy, and outline the future prospects and directions for a better understanding and re-purposing of metformin as an anti-cancer drug in the treatment of breast cancer.
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Affiliation(s)
- Samson Mathews Samuel
- Department of Physiology and Biophysics, Weill Cornell Medicine-Qatar, Education City, Qatar Foundation, Doha 24144, Qatar;
| | - Elizabeth Varghese
- Department of Physiology and Biophysics, Weill Cornell Medicine-Qatar, Education City, Qatar Foundation, Doha 24144, Qatar;
| | - Peter Kubatka
- Department of Medical Biology, Jessenius Faculty of Medicine, Comenius University in Bratislava, 03601 Martin, Slovakia;
| | - Chris R. Triggle
- Department of Pharmacology, Weill Cornell Medicine-Qatar, Education City, Qatar Foundation, Doha 24144, Qatar;
| | - Dietrich Büsselberg
- Department of Physiology and Biophysics, Weill Cornell Medicine-Qatar, Education City, Qatar Foundation, Doha 24144, Qatar;
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23
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Kazyken D, Magnuson B, Bodur C, Acosta-Jaquez HA, Zhang D, Tong X, Barnes TM, Steinl GK, Patterson NE, Altheim CH, Sharma N, Inoki K, Cartee GD, Bridges D, Yin L, Riddle SM, Fingar DC. AMPK directly activates mTORC2 to promote cell survival during acute energetic stress. Sci Signal 2019; 12:12/585/eaav3249. [PMID: 31186373 PMCID: PMC6935248 DOI: 10.1126/scisignal.aav3249] [Citation(s) in RCA: 145] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
AMP-activated protein kinase (AMPK) senses energetic stress and, in turn, promotes catabolic and suppresses anabolic metabolism coordinately to restore energy balance. We found that a diverse array of AMPK activators increased mTOR complex 2 (mTORC2) signaling in an AMPK-dependent manner in cultured cells. Activation of AMPK with the type 2 diabetes drug metformin (GlucoPhage) also increased mTORC2 signaling in liver in vivo and in primary hepatocytes in an AMPK-dependent manner. AMPK-mediated activation of mTORC2 did not result from AMPK-mediated suppression of mTORC1 and thus reduced negative feedback on PI3K flux. Rather, AMPK associated with and directly phosphorylated mTORC2 (mTOR in complex with rictor). As determined by two-stage in vitro kinase assay, phosphorylation of mTORC2 by recombinant AMPK was sufficient to increase mTORC2 catalytic activity toward Akt. Hence, AMPK phosphorylated mTORC2 components directly to increase mTORC2 activity and downstream signaling. Functionally, inactivation of AMPK, mTORC2, and Akt increased apoptosis during acute energetic stress. By showing that AMPK activates mTORC2 to increase cell survival, these data provide a potential mechanism for how AMPK paradoxically promotes tumorigenesis in certain contexts despite its tumor-suppressive function through inhibition of growth-promoting mTORC1. Collectively, these data unveil mTORC2 as a target of AMPK and the AMPK-mTORC2 axis as a promoter of cell survival during energetic stress.
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Affiliation(s)
- Dubek Kazyken
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109-2200, USA
| | - Brian Magnuson
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109-2200, USA
| | - Cagri Bodur
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109-2200, USA
| | - Hugo A. Acosta-Jaquez
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109-2200, USA
| | - Deqiang Zhang
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48109-2200, USA
| | - Xin Tong
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48109-2200, USA
| | - Tammy M. Barnes
- Department of Internal Medicine and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48109-2200, USA
| | - Gabrielle K. Steinl
- Department of Internal Medicine and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48109-2200, USA
| | - Nicole E. Patterson
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109-2200, USA
| | - Christopher H. Altheim
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109-2200, USA
| | - Naveen Sharma
- School of Kinesiology, Department of Molecular and Integrative Physiology, Institute of Gerontology, University of Michigan, Ann Arbor, MI 48109-2200, USA
| | - Ken Inoki
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48109-2200, USA
| | - Gregory D. Cartee
- School of Kinesiology, Department of Molecular and Integrative Physiology, Institute of Gerontology, University of Michigan, Ann Arbor, MI 48109-2200, USA
| | - Dave Bridges
- Department of Nutritional Sciences, University of Michigan, Ann Arbor, MI 48109-2200, USA
| | - Lei Yin
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48109-2200, USA
| | | | - Diane C. Fingar
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109-2200, USA.,Corresponding author.
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24
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Wang Y, Zhang H. Regulation of Autophagy by mTOR Signaling Pathway. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1206:67-83. [PMID: 31776980 DOI: 10.1007/978-981-15-0602-4_3] [Citation(s) in RCA: 198] [Impact Index Per Article: 39.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Autophagy plays a crucial role in maintaining cellular homeostasis, and is closely related to the occurrence of variety of human diseases. It is known that autophagy occurs in response to various environmental stresses such as nutrient deficiency, growth factor deficiency, and hypoxia. Induced autophagy eliminates the damage caused by these stresses and returns to normal levels when the stresses are relieved. To comprehend the induction of autophagy under various stress conditions and the effects of autophagy on the life processes of cells, it is necessary to understand how autophagy is regulated. Many studies have shown that a number of signal transduction pathways are involved in the regulation of autophagy. Among these pathways, some pathways converge at the target of rapamycin (TOR), a highly conserved kinase important for autophagy regulation. This review will focus on the role of TOR signaling pathway in the regulation of autophagy.
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Affiliation(s)
- Ying Wang
- Department of Physiology, Chinese Academy of Medical Sciences and Peking Union Medical College, Institute of Basic Medical Sciences, Beijing, China.,Department of Molecular Orthopedics, Beijing Research Institute of Traumatology and Orthopaedics, Beijing, China
| | - Hongbing Zhang
- Department of Physiology, Chinese Academy of Medical Sciences and Peking Union Medical College, Institute of Basic Medical Sciences, Beijing, China.
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