51
|
Jung S, Gámez-Díaz L, Proietti M, Grimbacher B. "Immune TOR-opathies," a Novel Disease Entity in Clinical Immunology. Front Immunol 2018; 9:966. [PMID: 29867948 PMCID: PMC5954032 DOI: 10.3389/fimmu.2018.00966] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 04/18/2018] [Indexed: 12/30/2022] Open
Abstract
Primary immunodeficiencies (PIDs) represent a group of mostly monogenic disorders caused by loss- or gain-of-function mutations in over 340 known genes that lead to abnormalities in the development and/or the function of the immune system. However, mutations in different genes can affect the same cell-signaling pathway and result in overlapping clinical phenotypes. In particular, mutations in the genes encoding for members of the phosphoinositide3-kinase (PI3K)/AKT/mTOR/S6 kinase (S6K) signaling cascade or for molecules interacting with this pathway have been associated with different PIDs that are often characterized by the coexistence of both immune deficiency and autoimmunity. The serine/threonine kinase mechanistic/mammalian target of rapamycin (mTOR), which acts downstream of PI3K and AKT, is emerging as a key regulator of immune responses. It integrates a variety of signals from the microenvironment to control cell growth, proliferation, and metabolism. mTOR plays therefore a central role in the regulation of immune cells’ differentiation and functions. Here, we review the different PIDs that share an impairment of the PI3K/AKT/mTOR/S6K pathway and we propose to name them “immune TOR-opathies” by analogy with a group of neurological disorders that has been originally defined by PB Crino and that are due to aberrant mTOR signaling (1). A better understanding of the role played by this complex intracellular cascade in the pathophysiology of “immune TOR-opathies” is crucial to develop targeted therapies.
Collapse
Affiliation(s)
- Sophie Jung
- CNRS, UPR 3572 (I2CT), Institut de Biologie Moléculaire et Cellulaire (IBMC), Strasbourg, France.,Hôpitaux Universitaires de Strasbourg, Pôle de Médecine et de Chirurgie Bucco-Dentaires, Strasbourg - Université de Strasbourg, Faculté de Chirurgie Dentaire, Strasbourg, France.,Center for Chronic Immunodeficiency (CCI), Medical Center - Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Laura Gámez-Díaz
- Center for Chronic Immunodeficiency (CCI), Medical Center - Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Michele Proietti
- Center for Chronic Immunodeficiency (CCI), Medical Center - Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Bodo Grimbacher
- Center for Chronic Immunodeficiency (CCI), Medical Center - Faculty of Medicine, University of Freiburg, Freiburg, Germany
| |
Collapse
|
52
|
Celik S, Celikkan FT, Ozkavukcu S, Can A, Celik-Ozenci C. Expression of inhibitor proteins that control primordial follicle reserve decreases in cryopreserved ovaries after autotransplantation. J Assist Reprod Genet 2018; 35:615-626. [PMID: 29497951 DOI: 10.1007/s10815-018-1140-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 02/14/2018] [Indexed: 01/12/2023] Open
Abstract
PURPOSE Even with 86 live births reported globally so far, the mechanism of primordial follicle loss following autotransplantation of the frozen-thawed ovarian tissue needs further evaluation. Pten, Tsc1, p27, and Amh are the inhibitor proteins that play crucial roles in suppressing the transition from the primordial follicle to primary state, maintaining the primordial follicle reserve. In this study, we aimed to evaluate whether the expression patterns of these proteins change and it may be related to the global primordial follicle loss after autotransplantation of the frozen-thawed ovarian tissue. METHODS Four groups were established in rats: fresh-control, frozen/thawed, fresh-transplanted, and frozen/thawed and transplanted. After slow freezing and thawing process, two ovarian pieces were transplanted into the back muscle of the same rat. After 2 weeks, grafts were harvested, fixed, and embedded into the paraffin block. Normal and atretic primordial/growing follicle count was performed in all groups. Ovarian tissues were evaluated for the dynamic expressions of the Pten, Tsc1, p27, and Amh proteins using immunohistochemistry, and H-score analyses were done. RESULTS Ovarian tissue cryopreservation does not change the expression patterns of inhibitory proteins that control ovarian reserve. Both in fresh and frozen/thawed autotransplanted groups, the expression of inhibitory proteins and Amh decreased significantly in primordial follicles and in growing follicles, respectively. In control group and in frozen/thawed group, primordial follicle counts were similar but decreased by almost half in both fresh-transplanted and frozen/thawed and transplanted groups. CONCLUSIONS One of the causes of primordial follicle loss after transplantation of ovarian graft may be decreased expression of the inhibitory proteins that guard the ovarian reserve and transplantation itself seems to be the major cause for disruption of inhibitory molecular signaling. Our findings highlight important molecular aspects for future clinical applications for fertility preservation in humans.
Collapse
Affiliation(s)
- Soner Celik
- Department of Histology and Embryology, School of Medicine, Akdeniz University, Campus, 07070, Antalya, Turkey
| | - Ferda Topal Celikkan
- Department of Histology and Embryology, Ankara University School of Medicine, 06100, Ankara, Turkey
| | - Sinan Ozkavukcu
- Department of Obstetrics and Gynecology, Centre for Assisted Reproduction, School of Medicine, Ankara University, 06100, Ankara, Turkey
| | - Alp Can
- Department of Histology and Embryology, Ankara University School of Medicine, 06100, Ankara, Turkey
| | - Ciler Celik-Ozenci
- Department of Histology and Embryology, School of Medicine, Akdeniz University, Campus, 07070, Antalya, Turkey.
| |
Collapse
|
53
|
Pompura SL, Dominguez-Villar M. The PI3K/AKT signaling pathway in regulatory T-cell development, stability, and function. J Leukoc Biol 2018; 103:1065-1076. [PMID: 29357116 DOI: 10.1002/jlb.2mir0817-349r] [Citation(s) in RCA: 166] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 12/08/2017] [Accepted: 12/14/2017] [Indexed: 12/11/2022] Open
Abstract
The PI3K/AKT signaling pathway is an essential node in mammalian cells that controls cell growth, migration, proliferation, and metabolism. During the last decade, a number of works have demonstrated an important role for the PI3K/AKT pathway in regulatory T cell development, function, and stability. This review summarizes our current knowledge of how the PI3K/AKT pathway regulates thymic and peripheral Treg generation and function, with an emphasis on translation of these observations to therapies targeting Tregs in several pathologies.
Collapse
Affiliation(s)
- Saige L Pompura
- Department of Immunobiology, Yale School of Medicine, New Haven, Connecticut, USA
- Department of Neurology, Human and Translational Immunology Program, Yale School of Medicine, New Haven, Connecticut, USA
| | - Margarita Dominguez-Villar
- Department of Neurology, Human and Translational Immunology Program, Yale School of Medicine, New Haven, Connecticut, USA
| |
Collapse
|
54
|
López-Sánchez E, Francés-Muñoz E, Menezo J, Pinazo-Durán M. Optic Nerve Alterations in PTEN+/–Mice. Eur J Ophthalmol 2018. [DOI: 10.1177/112067210601600313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
| | | | - J.L. Menezo
- Hospital “La Fe”
- Fundación Oftalmológica del Mediterráneo (FOM)
| | | |
Collapse
|
55
|
Tran CW, Saibil SD, Le Bihan T, Hamilton SR, Lang KS, You H, Lin AE, Garza KM, Elford AR, Tai K, Parsons ME, Wigmore K, Vainberg MG, Penninger JM, Woodgett JR, Mak TW, Ohashi PS. Glycogen Synthase Kinase-3 Modulates Cbl-b and Constrains T Cell Activation. THE JOURNAL OF IMMUNOLOGY 2017; 199:4056-4065. [DOI: 10.4049/jimmunol.1600396] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 10/05/2017] [Indexed: 11/19/2022]
|
56
|
Neben CL, Lo M, Jura N, Klein OD. Feedback regulation of RTK signaling in development. Dev Biol 2017; 447:71-89. [PMID: 29079424 DOI: 10.1016/j.ydbio.2017.10.017] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 10/17/2017] [Accepted: 10/23/2017] [Indexed: 02/07/2023]
Abstract
Precise regulation of the amplitude and duration of receptor tyrosine kinase (RTK) signaling is critical for the execution of cellular programs and behaviors. Understanding these control mechanisms has important implications for the field of developmental biology, and in recent years, the question of how augmentation or attenuation of RTK signaling via feedback loops modulates development has become of increasing interest. RTK feedback regulation is also important for human disease research; for example, germline mutations in genes that encode RTK signaling pathway components cause numerous human congenital syndromes, and somatic alterations contribute to the pathogenesis of diseases such as cancers. In this review, we survey regulators of RTK signaling that tune receptor activity and intracellular transduction cascades, with a focus on the roles of these genes in the developing embryo. We detail the diverse inhibitory mechanisms utilized by negative feedback regulators that, when lost or perturbed, lead to aberrant increases in RTK signaling. We also discuss recent biochemical and genetic insights into positive regulators of RTK signaling and how these proteins function in tandem with negative regulators to guide embryonic development.
Collapse
Affiliation(s)
- Cynthia L Neben
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco 94143, USA
| | - Megan Lo
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco 94143, USA; Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Natalia Jura
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA.
| | - Ophir D Klein
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco 94143, USA; Department of Pediatrics and Institute for Human Genetics, University of California, San Francisco, San Francisco 94143, USA.
| |
Collapse
|
57
|
Kim HS, Jang SW, Lee W, Kim K, Sohn H, Hwang SS, Lee GR. PTEN drives Th17 cell differentiation by preventing IL-2 production. J Exp Med 2017; 214:3381-3398. [PMID: 29018045 PMCID: PMC5679178 DOI: 10.1084/jem.20170523] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 07/14/2017] [Accepted: 08/14/2017] [Indexed: 12/17/2022] Open
Abstract
Th17 cells mediate inflammation and autoimmunity. Although it was known that cytokine IL-2 inhibits Th17 cell differentiation, how it does so was elusive. Using IL-17–specific PTEN-deficient mice, Kim et al. show that phosphatase PTEN inhibits IL-2 production and thus promotes Th17 cell differentiation. T helper 17 (Th17) cells are a CD4+ T cell subset that produces IL-17A to mediate inflammation and autoimmunity. IL-2 inhibits Th17 cell differentiation. However, the mechanism by which IL-2 is suppressed during Th17 cell differentiation remains unclear. Here, we show that phosphatase and tensin homologue (PTEN) is a key factor that regulates Th17 cell differentiation by suppressing IL-2 production. Th17-specific Pten deletion (Ptenfl/flIl17acre) impairs Th17 cell differentiation in vitro and ameliorated symptoms of experimental autoimmune encephalomyelitis (EAE), a model of Th17-mediated autoimmune disease. Mechanistically, Pten deficiency up-regulates IL-2 and phosphorylation of STAT5, but reduces STAT3 phosphorylation, thereby inhibiting Th17 cell differentiation. PTEN inhibitors block Th17 cell differentiation in vitro and in the EAE model. Thus, PTEN plays a key role in Th17 cell differentiation by blocking IL-2 expression.
Collapse
Affiliation(s)
- Hyeong Su Kim
- Department of Life Science, Sogang University, Seoul, South Korea
| | - Sung Woong Jang
- Department of Life Science, Sogang University, Seoul, South Korea
| | - Wonyong Lee
- Department of Life Science, Sogang University, Seoul, South Korea
| | - Kiwan Kim
- Department of Life Science, Sogang University, Seoul, South Korea
| | - Hyogon Sohn
- Department of Life Science, Sogang University, Seoul, South Korea
| | - Soo Seok Hwang
- Department of Life Science, Sogang University, Seoul, South Korea
| | - Gap Ryol Lee
- Department of Life Science, Sogang University, Seoul, South Korea
| |
Collapse
|
58
|
Mendes RD, Canté-Barrett K, Pieters R, Meijerink JPP. The relevance of PTEN-AKT in relation to NOTCH1-directed treatment strategies in T-cell acute lymphoblastic leukemia. Haematologica 2017; 101:1010-7. [PMID: 27582570 DOI: 10.3324/haematol.2016.146381] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 06/01/2016] [Indexed: 11/09/2022] Open
Abstract
The tumor suppressor phosphatase and tensin homolog (PTEN) negatively regulates phosphatidylinositol 3-kinase (PI3K)-AKT signaling and is often inactivated by mutations (including deletions) in a variety of cancer types, including T-cell acute lymphoblastic leukemia. Here we review mutation-associated mechanisms that inactivate PTEN together with other molecular mechanisms that activate AKT and contribute to T-cell leukemogenesis. In addition, we discuss how Pten mutations in mouse models affect the efficacy of gamma-secretase inhibitors to block NOTCH1 signaling through activation of AKT. Based on these models and on observations in primary diagnostic samples from patients with T-cell acute lymphoblastic leukemia, we speculate that PTEN-deficient cells employ an intrinsic homeostatic mechanism in which PI3K-AKT signaling is dampened over time. As a result of this reduced PI3K-AKT signaling, the level of AKT activation may be insufficient to compensate for NOTCH1 inhibition, resulting in responsiveness to gamma-secretase inhibitors. On the other hand, de novo acquired PTEN-inactivating events in NOTCH1-dependent leukemia could result in temporary, strong activation of PI3K-AKT signaling, increased glycolysis and glutaminolysis, and consequently gamma-secretase inhibitor resistance. Due to the central role of PTEN-AKT signaling and in the resistance to NOTCH1 inhibition, AKT inhibitors may be a promising addition to current treatment protocols for T-cell acute lymphoblastic leukemia.
Collapse
Affiliation(s)
- Rui D Mendes
- Department of Pediatric Oncology/Hematology, Erasmus MC Rotterdam-Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Kirsten Canté-Barrett
- Department of Pediatric Oncology/Hematology, Erasmus MC Rotterdam-Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Rob Pieters
- Department of Pediatric Oncology/Hematology, Erasmus MC Rotterdam-Sophia Children's Hospital, Rotterdam, The Netherlands Princess Máxima Center for Pediatric Oncology, Utrecht, The Netherlands
| | - Jules P P Meijerink
- Department of Pediatric Oncology/Hematology, Erasmus MC Rotterdam-Sophia Children's Hospital, Rotterdam, The Netherlands Princess Máxima Center for Pediatric Oncology, Utrecht, The Netherlands
| |
Collapse
|
59
|
Abstract
Since their ‘re-discovery’ more than two decades ago, FOXP3+ regulatory T cells (Tregs) have been an important subject of investigation in the biomedical field and our understanding of the mechanisms that drive their phenotype and function in health and disease has advanced tremendously. During the past few years it has become clear that Tregs are not a terminally differentiated population but show some degree of plasticity, and can, under specific environmental conditions, acquire the phenotype of effector T cells. In particular, recent works have highlighted the acquisition of a Th1-like phenotype by Tregs in several pathological environments. In this review we give an update on the concept of Treg plasticity and the advances in defining the molecular mechanisms that underlie the generation of Th1-like Tregs during an immune response and in different disease settings.
Collapse
Affiliation(s)
- Alexandra Kitz
- Departments of Neurology and Immunobiology, Yale School of Medicine, 300 George Street, New Haven, CT, 06519, USA
| | - Margarita Dominguez-Villar
- Department of Neurology, Human and Translational Immunology Program, Yale School of Medicine, 300 George Street, New Haven, CT, 06519, USA.
| |
Collapse
|
60
|
Munn DH, Sharma MD, Johnson TS, Rodriguez P. IDO, PTEN-expressing Tregs and control of antigen-presentation in the murine tumor microenvironment. Cancer Immunol Immunother 2017; 66:1049-1058. [PMID: 28488123 DOI: 10.1007/s00262-017-2010-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 05/02/2017] [Indexed: 01/16/2023]
Abstract
The tumor microenvironment is profoundly immunosuppressive. This creates a major barrier for attempts to combine immunotherapy with conventional chemotherapy or radiation, because the tumor antigens released by these cytotoxic agents are not cross-presented in an immunogenic fashion. In this Focused Research Review, we focus on mouse preclinical studies exploring the role of immunosuppressive Tregs expressing the PTEN lipid phosphatase, and the links between PTEN+ Tregs and the immunoregulatory enzyme indoleamine 2,3-dioxygenase (IDO). IDO has received attention because it can be expressed by a variety of human tumor types in vivo, but IDO can also be induced in host immune cells of both humans and mice in response to inflammation, infection or dying (apoptotic) cells. Mechanistically, IDO and PTEN+ Tregs are closely connected, with IDO causing activation of the PTEN pathway in Tregs. Genetic ablation or pharmacologic inhibition of PTEN in mouse Tregs destabilizes their suppressive phenotype, and this prevents transplantable and autochthonous tumors from creating their normal immunosuppressive microenvironment. Genetic ablation of either IDO or PTEN+ Tregs in mice results in a fundamental defect in the ability to maintain tolerance to antigens associated with apoptotic cells, including dying tumor cells. Consistent with this, pharmacologic inhibitors of either pathway show synergy when combined with cytotoxic agents such as chemotherapy or radiation. Thus, we propose that IDO and PTEN+ Tregs represent closely linked checkpoints that can influence the choice between immune activation versus tolerance to dying tumor cells.
Collapse
Affiliation(s)
- David H Munn
- Georgia Cancer Center, Medical College of Georgia, Augusta University, Room CN4141, Augusta, GA, 30912, USA. .,Department of Pediatrics, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA.
| | - Madhav D Sharma
- Georgia Cancer Center, Medical College of Georgia, Augusta University, Room CN4141, Augusta, GA, 30912, USA.,Department of Pediatrics, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Theodore S Johnson
- Georgia Cancer Center, Medical College of Georgia, Augusta University, Room CN4141, Augusta, GA, 30912, USA.,Department of Pediatrics, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Paulo Rodriguez
- Georgia Cancer Center, Medical College of Georgia, Augusta University, Room CN4141, Augusta, GA, 30912, USA
| |
Collapse
|
61
|
Petersen F, Yue X, Riemekasten G, Yu X. Dysregulated homeostasis of target tissues or autoantigens - A novel principle in autoimmunity. Autoimmun Rev 2017; 16:602-611. [PMID: 28411168 DOI: 10.1016/j.autrev.2017.04.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Accepted: 03/11/2017] [Indexed: 01/22/2023]
Abstract
Monogenic autoimmune disorders provide a powerful tool for our understanding of the principles of autoimmunity due to the obvious impact of a single gene on the disease. So far, approximately 100 single gene defects causing murine monogenic autoimmune disorders have been reported and the functional characterization of these genes will provide significant progress in understanding the nature of autoimmunity. According to their function, genes leading to monogenic autoimmune disorders can be categorized into two groups. An expectable first group contains genes involved in the homeostasis of the immune system, including homeostasis of immune organs and immune cells. Intriguingly, the second group consists of genes functionally involved in the homeostasis of target tissues or autoantigens. According to our novel hypothesis, we propose that autoimmunity represents a consequence of a dysregulated homeostasis of the immune system and/or its targets including autoantigens and target tissues. In this review we refer to both aspects of homeostasis in autoimmunity with a highlight on the role of the homeostasis of target tissues and autoantigens.
Collapse
Affiliation(s)
- Frank Petersen
- Priority Area Asthma & Allergy, Research Center Borstel, Airway Research Center North (ARCN), Members of the German Center for Lung Research (DZL), 23845 Borstel, Germany
| | - Xiaoyang Yue
- Priority Area Asthma & Allergy, Research Center Borstel, Airway Research Center North (ARCN), Members of the German Center for Lung Research (DZL), 23845 Borstel, Germany
| | - Gabriela Riemekasten
- Priority Area Asthma & Allergy, Research Center Borstel, Airway Research Center North (ARCN), Members of the German Center for Lung Research (DZL), 23845 Borstel, Germany; Department of Rheumatology, University of Lübeck, 23538 Lübeck, Germany
| | - Xinhua Yu
- Priority Area Asthma & Allergy, Research Center Borstel, Airway Research Center North (ARCN), Members of the German Center for Lung Research (DZL), 23845 Borstel, Germany; Xiamen-Borstel Joint Laboratory of Autoimmunity, Medical College of Xiamen University, Xiamen 361102, China.
| |
Collapse
|
62
|
Brandmaier A, Hou SQ, Demaria S, Formenti SC, Shen WH. PTEN at the interface of immune tolerance and tumor suppression. ACTA ACUST UNITED AC 2017. [PMID: 29527223 DOI: 10.1007/s11515-017-1443-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND PTEN is well known to function as a tumor suppressor that antagonizes oncogenic signaling and maintains genomic stability. The PTEN gene is frequently deleted or mutated in human cancers and the wide cancer spectrum associated with PTEN deficiency has been recapitulated in a variety of mouse models of Pten deletion or mutation. Pten mutations are highly penetrant in causing various types of spontaneous tumors that often exhibit resistance to anticancer therapies including immunotherapy. Recent studies demonstrate that PTEN also regulates immune functionality. OBJECTIVE To understand the multifaceted functions of PTEN as both a tumor suppressor and an immune regulator. METHODS This review will summarize the emerging knowledge of PTEN function in cancer immunoediting. In addition, the mechanisms underlying functional integration of various PTEN pathways in regulating cancer evolution and tumor immunity will be highlighted. RESULTS Recent preclinical and clinical studies revealed the essential role of PTEN in maintaining immune homeostasis, which significantly expands the repertoire of PTEN functions. Mechanistically, aberrant PTEN signaling alters the interplay between the immune system and tumors, leading to immunosuppression and tumor escape. CONCLUSION Rational design of personalized anti-cancer treatment requires mechanistic understanding of diverse PTEN signaling pathways in modulation of the crosstalk between tumor and immune cells.
Collapse
Affiliation(s)
- Andrew Brandmaier
- Department of Radiation Oncology, Weill Cornell Medicine, Cornell University, New York, NY 10065, USA
| | - Sheng-Qi Hou
- Department of Radiation Oncology, Weill Cornell Medicine, Cornell University, New York, NY 10065, USA
| | - Sandra Demaria
- Department of Radiation Oncology, Weill Cornell Medicine, Cornell University, New York, NY 10065, USA
| | - Silvia C Formenti
- Department of Radiation Oncology, Weill Cornell Medicine, Cornell University, New York, NY 10065, USA
| | - Wen H Shen
- Department of Radiation Oncology, Weill Cornell Medicine, Cornell University, New York, NY 10065, USA
| |
Collapse
|
63
|
Vila IK, Yao Y, Kim G, Xia W, Kim H, Kim SJ, Park MK, Hwang JP, González-Billalabeitia E, Hung MC, Song SJ, Song MS. A UBE2O-AMPKα2 Axis that Promotes Tumor Initiation and Progression Offers Opportunities for Therapy. Cancer Cell 2017; 31:208-224. [PMID: 28162974 PMCID: PMC5463996 DOI: 10.1016/j.ccell.2017.01.003] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 10/10/2016] [Accepted: 01/05/2017] [Indexed: 01/06/2023]
Abstract
UBE2O is localized in the 17q25 locus, which is known to be amplified in human cancers, but its role in tumorigenesis remains undefined. Here we show that Ube2o deletion in MMTV-PyVT or TRAMP mice profoundly impairs tumor initiation, growth, and metastasis, while switching off the metabolic reprogramming of tumor cells. Mechanistically, UBE2O specifically targets AMPKα2 for ubiquitination and degradation, and thereby promotes activation of the mTOR-HIF1α pathway. Notably, inactivation of AMPKα2, but not AMPKα1, abrogates the tumor attenuation caused by UBE2O loss, while treatment with rapamycin or inhibition of HIF1α ablates UBE2O-dependent tumor biology. Finally, pharmacological blockade of UBE2O inhibits tumorigenesis through the restoration of AMPKα2, suggesting the UBE2O-AMPKα2 axis as a potential cancer therapeutic target.
Collapse
Affiliation(s)
- Isabelle K Vila
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Yixin Yao
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Goeun Kim
- Soonchunhyang Institute of Medi-bio Science, Soonchunhyang University, Cheonan-si, Chungcheongnam-do 31151, Republic of Korea
| | - Weiya Xia
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Hyejin Kim
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Sun-Joong Kim
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Mi-Kyung Park
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - James P Hwang
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | | | - Mien-Chie Hung
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Cancer Biology Program, The University of Texas Graduate School of Biomedical Sciences, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Center for Molecular Medicine and Graduate Institute of Cancer Biology, China Medical University, Taichung 404, Taiwan
| | - Su Jung Song
- Soonchunhyang Institute of Medi-bio Science, Soonchunhyang University, Cheonan-si, Chungcheongnam-do 31151, Republic of Korea.
| | - Min Sup Song
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Cancer Biology Program, The University of Texas Graduate School of Biomedical Sciences, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| |
Collapse
|
64
|
Gao L, Ren W, Zhang L, Li S, Kong X, Zhang H, Dong J, Cai G, Jin C, Zheng D, Zhi K. PTENp1, a natural sponge of miR‐21, mediates PTEN expression to inhibit the proliferation of oral squamous cell carcinoma. Mol Carcinog 2016; 56:1322-1334. [PMID: 27862321 DOI: 10.1002/mc.22594] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2016] [Revised: 11/02/2016] [Accepted: 11/11/2016] [Indexed: 12/21/2022]
Affiliation(s)
- Ling Gao
- Department of Oral Maxillofacial SurgeryThe Affiliated Hospital of Qingdao UniversityQingdao, ShandongP. R. China
- Department of Oral Maxillofacial Surgery, Stomatological Hospital, College of MedicineXi'an Jiaotong UniversityXi'an, ShaanxiP. R. China
| | - Wenhao Ren
- Department of Oral Maxillofacial SurgeryThe Affiliated Hospital of Qingdao UniversityQingdao, ShandongP. R. China
- Department of Oral Maxillofacial Surgery, Stomatological Hospital, College of MedicineXi'an Jiaotong UniversityXi'an, ShaanxiP. R. China
| | - Linmei Zhang
- Department of Oral Maxillofacial Surgery, Stomatological Hospital, College of MedicineXi'an Jiaotong UniversityXi'an, ShaanxiP. R. China
| | - Shaoming Li
- Department of Oral Maxillofacial SurgeryThe Affiliated Hospital of Qingdao UniversityQingdao, ShandongP. R. China
| | - Xinjuan Kong
- Department of GastroenterologyThe Affiliated Hospital of Qingdao UniversityQingdao, ShandongP. R. China
| | - Hao Zhang
- Department of Oral Maxillofacial Surgery, Stomatological Hospital, College of MedicineXi'an Jiaotong UniversityXi'an, ShaanxiP. R. China
| | - Jianwei Dong
- Department of Oral Maxillofacial Surgery, Stomatological Hospital, College of MedicineXi'an Jiaotong UniversityXi'an, ShaanxiP. R. China
| | - Guangfeng Cai
- Department of Oral Maxillofacial Surgery, Stomatological Hospital, College of MedicineXi'an Jiaotong UniversityXi'an, ShaanxiP. R. China
| | - Changxiong Jin
- Department of Oral Maxillofacial Surgery, Stomatological Hospital, College of MedicineXi'an Jiaotong UniversityXi'an, ShaanxiP. R. China
| | - Danqing Zheng
- Department of Oral Maxillofacial Surgery, Stomatological Hospital, College of MedicineXi'an Jiaotong UniversityXi'an, ShaanxiP. R. China
| | - Keqian Zhi
- Department of Oral Maxillofacial SurgeryThe Affiliated Hospital of Qingdao UniversityQingdao, ShandongP. R. China
- Department of Oral Maxillofacial Surgery, Stomatological Hospital, College of MedicineXi'an Jiaotong UniversityXi'an, ShaanxiP. R. China
| |
Collapse
|
65
|
Avan A, Narayan R, Giovannetti E, Peters GJ. Role of Akt signaling in resistance to DNA-targeted therapy. World J Clin Oncol 2016; 7:352-369. [PMID: 27777878 PMCID: PMC5056327 DOI: 10.5306/wjco.v7.i5.352] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 06/06/2016] [Accepted: 08/01/2016] [Indexed: 02/06/2023] Open
Abstract
The Akt signal transduction pathway controls most hallmarks of cancer. Activation of the Akt cascade promotes a malignant phenotype and is also widely implicated in drug resistance. Therefore, the modulation of Akt activity is regarded as an attractive strategy to enhance the efficacy of cancer therapy and irradiation. This pathway consists of phosphatidylinositol 3 kinase (PI3K), mammalian target of rapamycin, and the transforming serine-threonine kinase Akt protein isoforms, also known as protein kinase B. DNA-targeted agents, such as platinum agents, taxanes, and antimetabolites, as well as radiation have had a significant impact on cancer treatment by affecting DNA replication, which is aberrantly activated in malignancies. However, the caveat is that they may also trigger the activation of repairing mechanisms, such as upstream and downstream cascade of Akt survival pathway. Thus, each target can theoretically be inhibited in view of improving the potency of conventional treatment. Akt inhibitors, e.g., MK-2206 and perifosine, or PI3K modulators, e.g., LY294002 and Wortmannin, have shown some promising results in favor of sensitizing the cancer cells to the therapy in vitro and in vivo, which have provided the rationale for incorporation of these novel agents into multimodality treatment of different malignancies. Nevertheless, despite the acceptable safety profile of some of these agents in the clinical studies, with regard to the efficacy, the results are still too preliminary. Hence, we need to wait for the upcoming data from the ongoing trials before utilizing them into the standard care of cancer patients.
Collapse
|
66
|
Muñoz-Fontela C, Mandinova A, Aaronson SA, Lee SW. Emerging roles of p53 and other tumour-suppressor genes in immune regulation. Nat Rev Immunol 2016; 16:741-750. [PMID: 27667712 DOI: 10.1038/nri.2016.99] [Citation(s) in RCA: 244] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Tumour-suppressor genes are indispensable for the maintenance of genomic integrity. Recently, several of these genes, including those encoding p53, PTEN, RB1 and ARF, have been implicated in immune responses and inflammatory diseases. In particular, the p53 tumour- suppressor pathway is involved in crucial aspects of tumour immunology and in homeostatic regulation of immune responses. Other studies have identified roles for p53 in various cellular processes, including metabolism and stem cell maintenance. Here, we discuss the emerging roles of p53 and other tumour-suppressor genes in tumour immunology, as well as in additional immunological settings, such as virus infection. This relatively unexplored area could yield important insights into the homeostatic control of immune cells in health and disease and facilitate the development of more effective immunotherapies. Consequently, tumour-suppressor genes are emerging as potential guardians of immune integrity.
Collapse
Affiliation(s)
- César Muñoz-Fontela
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Martinistrasse 52, 20251 Hamburg, Germany
| | - Anna Mandinova
- Cutaneous Biology Research Center, Massachusetts General Hospital and Harvard Medical School, Building 149 13th Street, Charlestown, Massachusetts 02129, USA.,Harvard Stem Cell Institute, 7 Divinity Avenue, Cambridge, Massachusetts 02138, USA.,Broad Institute of Harvard and MIT, 7 Cambridge Center, Cambridge, Massachusetts 02142, USA
| | - Stuart A Aaronson
- Department of Oncological Sciences, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, New York 10029, USA
| | - Sam W Lee
- Cutaneous Biology Research Center, Massachusetts General Hospital and Harvard Medical School, Building 149 13th Street, Charlestown, Massachusetts 02129, USA.,Broad Institute of Harvard and MIT, 7 Cambridge Center, Cambridge, Massachusetts 02142, USA
| |
Collapse
|
67
|
Immune dysregulation in patients with PTEN hamartoma tumor syndrome: Analysis of FOXP3 regulatory T cells. J Allergy Clin Immunol 2016; 139:607-620.e15. [PMID: 27477328 PMCID: PMC5292998 DOI: 10.1016/j.jaci.2016.03.059] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 01/25/2016] [Accepted: 03/22/2016] [Indexed: 12/14/2022]
Abstract
Background Patients with heterozygous germline mutations in phosphatase and tensin homolog deleted on chromosome 10 (PTEN) experience autoimmunity and lymphoid hyperplasia. Objectives Because regulation of the phosphoinositide 3-kinase (PI3K) pathway is critical for maintaining regulatory T (Treg) cell functions, we investigate Treg cells in patients with heterozygous germline PTEN mutations (PTEN hamartoma tumor syndrome [PHTS]). Methods Patients with PHTS were assessed for immunologic conditions, lymphocyte subsets, forkhead box P3 (FOXP3)+ Treg cell levels, and phenotype. To determine the functional importance of phosphatases that control the PI3K pathway, we assessed Treg cell induction in vitro, mitochondrial depolarization, and recruitment of PTEN to the immunologic synapse. Results Autoimmunity and peripheral lymphoid hyperplasia were found in 43% of 79 patients with PHTS. Immune dysregulation in patients with PHTS included lymphopenia, CD4+ T-cell reduction, and changes in T- and B-cell subsets. Although total CD4+FOXP3+ Treg cell numbers are reduced, frequencies are maintained in the blood and intestine. Despite pathogenic PTEN mutations, the FOXP3+ T cells are phenotypically normal. We show that the phosphatase PH domain leucine-rich repeat protein phosphatase (PHLPP) downstream of PTEN is highly expressed in normal human Treg cells and provides complementary phosphatase activity. PHLPP is indispensable for the differentiation of induced Treg cells in vitro and Treg cell mitochondrial fitness. PTEN and PHLPP form a phosphatase network that is polarized at the immunologic synapse. Conclusion Heterozygous loss of function of PTEN in human subjects has a significant effect on T- and B-cell immunity. Assembly of the PTEN-PHLPP phosphatase network allows coordinated phosphatase activities at the site of T-cell receptor activation, which is important for limiting PI3K hyperactivation in Treg cells despite PTEN haploinsufficiency.
Collapse
|
68
|
Kitz A, de Marcken M, Gautron AS, Mitrovic M, Hafler DA, Dominguez-Villar M. AKT isoforms modulate Th1-like Treg generation and function in human autoimmune disease. EMBO Rep 2016; 17:1169-83. [PMID: 27312110 DOI: 10.15252/embr.201541905] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 05/13/2016] [Indexed: 12/22/2022] Open
Abstract
Foxp3(+) regulatory T cells (Tregs) exhibit plasticity, which dictates their function. Secretion of the inflammatory cytokine IFNγ, together with the acquisition of a T helper 1 (Th1)-like effector phenotype as observed in cancer, infection, and autoimmune diseases, is associated with loss of Treg suppressor function through an unknown mechanism. Here, we describe the signaling events driving the generation of human Th1-Tregs. Using a genome-wide gene expression approach and pathway analysis, we identify the PI3K/AKT/Foxo1/3 signaling cascade as the major pathway involved in IFNγ secretion by human Tregs. Furthermore, we describe the opposing roles of AKT isoforms in Th1-Treg generation ex vivo Finally, we employ multiple sclerosis as an in vivo model with increased but functionally defective Th1-Tregs. We show that the PI3K/AKT/Foxo1/3 pathway is activated in ex vivo-isolated Tregs from untreated relapsing-remitting MS patients and that blockade of the pathway inhibits IFNγ secretion and restores the immune suppressive function of Tregs. These data define a fundamental pathway regulating the function of human Tregs and suggest a novel treatment paradigm for autoimmune diseases.
Collapse
Affiliation(s)
- Alexandra Kitz
- Departments of Neurology and Immunobiology, Yale School of Medicine, New Haven, CT, USA
| | - Marine de Marcken
- Departments of Neurology and Immunobiology, Yale School of Medicine, New Haven, CT, USA
| | - Anne-Sophie Gautron
- Departments of Neurology and Immunobiology, Yale School of Medicine, New Haven, CT, USA
| | - Mitja Mitrovic
- Departments of Neurology and Immunobiology, Yale School of Medicine, New Haven, CT, USA
| | - David A Hafler
- Departments of Neurology and Immunobiology, Yale School of Medicine, New Haven, CT, USA
| | | |
Collapse
|
69
|
Hyperactive mTOR pathway promotes lymphoproliferation and abnormal differentiation in autoimmune lymphoproliferative syndrome. Blood 2016; 128:227-38. [PMID: 27099149 DOI: 10.1182/blood-2015-11-685024] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 04/14/2016] [Indexed: 12/23/2022] Open
Abstract
Autoimmune lymphoproliferative syndrome (ALPS) is a human disorder characterized by defective Fas signaling, resulting in chronic benign lymphoproliferation and accumulation of TCRαβ(+) CD4(-) CD8(-) double-negative T (DNT) cells. Although their phenotype resembles that of terminally differentiated or exhausted T cells, lack of KLRG1, high eomesodermin, and marginal T-bet expression point instead to a long-lived memory state with potent proliferative capacity. Here we show that despite their terminally differentiated phenotype, human ALPS DNT cells exhibit substantial mitotic activity in vivo. Notably, hyperproliferation of ALPS DNT cells is associated with increased basal and activation-induced phosphorylation of serine-threonine kinases Akt and mechanistic target of rapamycin (mTOR). The mTOR inhibitor rapamycin abrogated survival and proliferation of ALPS DNT cells, but not of CD4(+) or CD8(+) T cells in vitro. In vivo, mTOR inhibition reduced proliferation and abnormal differentiation by DNT cells. Importantly, increased mitotic activity and hyperactive mTOR signaling was also observed in recently defined CD4(+) or CD8(+) precursor DNT cells, and mTOR inhibition specifically reduced these cells in vivo, indicating abnormal programming of Fas-deficient T cells before the DNT stage. Thus, our results identify the mTOR pathway as a major regulator of lymphoproliferation and aberrant differentiation in ALPS.
Collapse
|
70
|
The microRNA miR-148a functions as a critical regulator of B cell tolerance and autoimmunity. Nat Immunol 2016; 17:433-40. [PMID: 26901150 PMCID: PMC4803625 DOI: 10.1038/ni.3385] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 12/18/2015] [Indexed: 12/14/2022]
Abstract
Autoreactive B cells have critical roles in a large diversity of autoimmune diseases, but the molecular pathways that control these cells remain poorly understood. We performed an in vivo functional screen of a lymphocyte-expressed microRNA library and identified miR-148a as a potent regulator of B cell tolerance. Elevated miR-148a expression impaired B cell tolerance by promoting the survival of immature B cells after engagement of the B cell antigen receptor by suppressing the expression of the autoimmune suppressor Gadd45α, the tumor suppressor PTEN and the pro-apoptotic protein Bim. Furthermore, increased expression of miR-148a, which occurs frequently in patients with lupus and lupus-prone mice, facilitated the development of lethal autoimmune disease in a mouse model of lupus. Our studies demonstrate a function for miR-148a as a regulator of B cell tolerance and autoimmunity.
Collapse
|
71
|
Sagar V, Bond JR, Chowdhary VR. A 50-Year-Old Woman With Cowden Syndrome and Joint Pains. Arthritis Care Res (Hoboken) 2016; 67:1604-8. [PMID: 25989067 DOI: 10.1002/acr.22616] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 04/25/2015] [Accepted: 05/05/2015] [Indexed: 01/01/2023]
Affiliation(s)
- Vinay Sagar
- Mayo Clinic College of Medicine, Rochester, Minnesota
| | | | | |
Collapse
|
72
|
Pulido R. PTEN: a yin-yang master regulator protein in health and disease. Methods 2016; 77-78:3-10. [PMID: 25843297 DOI: 10.1016/j.ymeth.2015.02.009] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 02/19/2015] [Indexed: 01/16/2023] Open
Abstract
The PTEN gene is a tumor suppressor gene frequently mutated in human tumors, which encodes a ubiquitous protein whose major activity is to act as a lipid phosphatase that counteracts the action of the oncogenic PI3K. In addition, PTEN displays protein phosphatase- and catalytically-independent activities. The physiologic control of PTEN function, and its inactivation in cancer and other human diseases, including some neurodevelopmental disorders, is upon the action of multiple regulatory mechanisms. This provides a wide spectrum of potential therapeutic approaches to reconstitute PTEN activity. By contrast, inhibition of PTEN function may be beneficial in a different group of human diseases, such as type 2 diabetes or neuroregeneration-related pathologies. This makes PTEN a functionally dual yin-yang protein with high potential in the clinics. Here, a brief overview on PTEN and its relation with human disease is presented.
Collapse
Affiliation(s)
- Rafael Pulido
- BioCruces Health Research Institute, Barakaldo, Spain; IKERBASQUE, Basque Foundation for Science, Bilbao, Spain.
| |
Collapse
|
73
|
Oncogenic PTEN functions and models in T-cell malignancies. Oncogene 2015; 35:3887-96. [PMID: 26616857 DOI: 10.1038/onc.2015.462] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 10/07/2015] [Accepted: 10/13/2015] [Indexed: 02/07/2023]
Abstract
PTEN is a protein phosphatase that is crucial to prevent the malignant transformation of T-cells. Although a numerous mechanisms regulate its expression and function, they are often altered in T-cell acute lymphoblastic leukaemias and T-cell lymphomas. As such, PTEN inactivation frequently occurs in these malignancies, where it can be associated with chemotherapy resistance and poor prognosis. Different Pten knockout models recapitulated the development of T-cell leukaemia/lymphoma, demonstrating that PTEN loss is at the center of a complex oncogenic network that sustains and drives tumorigenesis via the activation of multiple signalling pathways. These aspects and their therapeutic implications are discussed in this review.
Collapse
|
74
|
Browning MJ, Chandra A, Carbonaro V, Okkenhaug K, Barwell J. Cowden's syndrome with immunodeficiency. J Med Genet 2015; 52:856-9. [PMID: 26246517 DOI: 10.1136/jmedgenet-2015-103266] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 06/26/2015] [Indexed: 11/04/2022]
Abstract
BACKGROUND Cowden's syndrome is a rare, autosomal dominant disease caused by mutations in the phosphoinositide 3-kinase and phosphatase and tensin homolog (PTEN) gene. It is associated with hamartomatous polyposis of the gastrointestinal tract, mucocutaneous lesions and increased risk of developing certain types of cancer. In addition to increased risk of tumour development, mutations in PTEN have also been associated with autoimmunity in both mice and humans. Until now, however, an association between Cowden's syndrome and immune deficiency has been reported in a single patient only. METHODS AND RESULTS Two patients with Cowden's syndrome and an increased frequency of infections were investigated for possible underlying immunodeficiency. In one patient, hypogammaglobulinaemia with a functional antibody deficiency was identified, while the other patient had a persisting CD4+ T cell lymphopenia (with normal antibody production). CONCLUSIONS Our data indicate that Cowden's syndrome may be associated with both T cell and B cell immune dysfunction. We recommend that patients with Cowden's syndrome and an increased frequency of infections are investigated for associated immunodeficiency.
Collapse
Affiliation(s)
| | - Anita Chandra
- Department of Biochemistry and Immunology, Addenbrooke's Hospital, Cambridge, UK Laboratory of Lymphocyte Signalling and Development, Babraham Institute, Babraham, UK
| | - Valentina Carbonaro
- Laboratory of Lymphocyte Signalling and Development, Babraham Institute, Babraham, UK
| | - Klaus Okkenhaug
- Laboratory of Lymphocyte Signalling and Development, Babraham Institute, Babraham, UK
| | - Julian Barwell
- Department of Genetics, Leicester Royal Infirmary, Leicester, UK
| |
Collapse
|
75
|
Tilot AK, Frazier TW, Eng C. Balancing Proliferation and Connectivity in PTEN-associated Autism Spectrum Disorder. Neurotherapeutics 2015; 12:609-19. [PMID: 25916396 PMCID: PMC4489960 DOI: 10.1007/s13311-015-0356-8] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Germline mutations in PTEN, which encodes a widely expressed phosphatase, was mapped to 10q23 and identified as the susceptibility gene for Cowden syndrome, characterized by macrocephaly and high risks of breast, thyroid, and other cancers. The phenotypic spectrum of PTEN mutations expanded to include autism with macrocephaly only 10 years ago. Neurological studies of patients with PTEN-associated autism spectrum disorder (ASD) show increases in cortical white matter and a distinctive cognitive profile, including delayed language development with poor working memory and processing speed. Once a germline PTEN mutation is found, and a diagnosis of phosphatase and tensin homolog (PTEN) hamartoma tumor syndrome made, the clinical outlook broadens to include higher lifetime risks for multiple cancers, beginning in childhood with thyroid cancer. First described as a tumor suppressor, PTEN is a major negative regulator of the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (mTOR) signaling pathway-controlling growth, protein synthesis, and proliferation. This canonical function combines with less well-understood mechanisms to influence synaptic plasticity and neuronal cytoarchitecture. Several excellent mouse models of Pten loss or dysfunction link these neural functions to autism-like behavioral abnormalities, such as altered sociability, repetitive behaviors, and phenotypes like anxiety that are often associated with ASD in humans. These models also show the promise of mTOR inhibitors as therapeutic agents capable of reversing phenotypes ranging from overgrowth to low social behavior. Based on these findings, therapeutic options for patients with PTEN hamartoma tumor syndrome and ASD are coming into view, even as new discoveries in PTEN biology add complexity to our understanding of this master regulator.
Collapse
Affiliation(s)
- Amanda K. Tilot
- />Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 USA
- />Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine, Cleveland, OH 44195 USA
| | - Thomas W. Frazier
- />Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 USA
- />Center for Autism, Pediatric Institute, Cleveland Clinic, Cleveland, OH 44195 USA
- />Department of Pediatrics, Cleveland Clinic, Cleveland, OH 44195 USA
| | - Charis Eng
- />Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 USA
- />Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH 44195 USA
- />Stanley Shalom Zielony Institute of Nursing Excellence, Cleveland Clinic, Cleveland, OH 44195 USA
- />Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine, Cleveland, OH 44195 USA
- />Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH 44106 USA
- />Germline High Risk Focus Group, CASE Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH 44106 USA
| |
Collapse
|
76
|
Abstract
Understanding the cell-intrinsic cues that permit self-reactivity in lymphocytes, and therefore autoimmunity, requires an understanding of the transcriptional and posttranscriptional regulation of gene expression in these cells. In this Review, we address seminal and recent research on microRNA (miRNA) regulation of central and peripheral tolerance. Human and mouse studies demonstrate that the PI3K pathway is a critical point of miRNA regulation of immune cell development and function that affects the development of autoimmunity. We also discuss how miRNA expression profiling in human autoimmune diseases has inspired mechanistic studies of miRNA function in the pathogenesis of multiple sclerosis, rheumatoid arthritis, systemic lupus erythematosus, type 1 diabetes, and asthma.
Collapse
|
77
|
Lee T, Le EN, Glass DA, Bowen CD, Dominguez AR. Systemic lupus erythematosus in a patient with PTEN hamartoma tumour syndrome. Br J Dermatol 2015; 170:990-2. [PMID: 24641667 DOI: 10.1111/bjd.12767] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- T Lee
- University of Texas Southwestern Medical School, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-9191, U.S.A
| | | | | | | | | |
Collapse
|
78
|
Li Chew C, Lunardi A, Gulluni F, Ruan DT, Chen M, Salmena L, Nishino M, Papa A, Ng C, Fung J, Clohessy JG, Sasaki J, Sasaki T, Bronson RT, Hirsch E, Pandolfi PP. In Vivo Role of INPP4B in Tumor and Metastasis Suppression through Regulation of PI3K-AKT Signaling at Endosomes. Cancer Discov 2015; 5:740-51. [PMID: 25883022 DOI: 10.1158/2159-8290.cd-14-1347] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 04/01/2015] [Indexed: 11/16/2022]
Abstract
UNLABELLED The phosphatases PTEN and INPP4B have been proposed to act as tumor suppressors by antagonizing PI3K-AKT signaling and are frequently dysregulated in human cancer. Although PTEN has been extensively studied, little is known about the underlying mechanisms by which INPP4B exerts its tumor-suppressive function and its role in tumorigenesis in vivo. Here, we show that a partial or complete loss of Inpp4b morphs benign thyroid adenoma lesions in Pten heterozygous mice into lethal and metastatic follicular-like thyroid cancer (FTC). Importantly, analyses of human thyroid cancer cell lines and specimens reveal INPP4B downregulation in FTC. Mechanistically, we find that INPP4B, but not PTEN, is enriched in the early endosomes of thyroid cancer cells, where it selectively inhibits AKT2 activation and in turn tumor proliferation and anchorage-independent growth. We therefore identify INPP4B as a novel tumor suppressor in FTC oncogenesis and metastasis through localized regulation of the PI3K-AKT pathway at the endosomes. SIGNIFICANCE Although both PTEN and INPP4B can inhibit PI3K-AKT signaling through their lipid phosphatase activities, here we demonstrate lack of an epistatic relationship between the two tumor suppressors. Instead, the qualitative regulation of PI3K-AKT2 signaling by INPP4B provides a mechanism for their cooperation in suppressing thyroid tumorigenesis and metastasis.
Collapse
Affiliation(s)
- Chen Li Chew
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Departments of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Andrea Lunardi
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Departments of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Federico Gulluni
- Molecular Biotechnology Center, Department of Molecular Biotechnology and Health Sciences, University of Torino, Italy
| | - Daniel T Ruan
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Departments of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Ming Chen
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Departments of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Leonardo Salmena
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Departments of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Michiya Nishino
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Antonella Papa
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Departments of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Christopher Ng
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Departments of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Jacqueline Fung
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Departments of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - John G Clohessy
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Departments of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Junko Sasaki
- Department of Medical Biology, Akita University Graduate School of Medicine and Research Center for Biosignal, Akita University, Akita, Japan
| | - Takehiko Sasaki
- Department of Medical Biology, Akita University Graduate School of Medicine and Research Center for Biosignal, Akita University, Akita, Japan
| | - Roderick T Bronson
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts
| | - Emilio Hirsch
- Molecular Biotechnology Center, Department of Molecular Biotechnology and Health Sciences, University of Torino, Italy
| | - Pier Paolo Pandolfi
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Departments of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts.
| |
Collapse
|
79
|
Abstract
Induction of specific immune tolerance to grafts remains the sought-after standard following transplantation. Defined by expression of the Foxp3 (forkhead box protein 3) transcription factor, the regulatory T-cell (Treg) lineage has been noted to exert potent immunoregulatory functions that contribute to specific graft tolerance. In this review, we discuss the known signals and pathways which govern Treg development, both in the thymus and in peripheral sites, as well as lineage maintenance and homeostasis. In particular, we highlight the roles of T-cell receptor signaling, CD28 costimulation, and signals through phosphatidyl inositol 3-kinase (PI3K) and related metabolic pathways in multiple aspects of Treg biology.
Collapse
Affiliation(s)
- Alexandria Huynh
- Division of Medical Sciences, Harvard Medical School, Boston, MA, USA; Transplantation Biology Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | | | | |
Collapse
|
80
|
Wu T, Ye Y, Min SY, Zhu J, Khobahy E, Zhou J, Yan M, Hemachandran S, Pathak S, Zhou XJ, Andreeff M, Mohan C. Prevention of murine lupus nephritis by targeting multiple signaling axes and oxidative stress using a synthetic triterpenoid. Arthritis Rheumatol 2015; 66:3129-39. [PMID: 25047252 DOI: 10.1002/art.38782] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 07/08/2014] [Indexed: 01/10/2023]
Abstract
OBJECTIVE Current treatment options for lupus are far from optimal. Previously, we reported that phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin, MEK-1/ERK-1,2, p38, STAT-3, STAT-5, NF-κB, multiple Bcl-2 family members, and various cell cycle molecules were overexpressed in splenic B cells in an age-dependent and gene dose-dependent manner in mouse strains with spontaneous lupus. Since the synthetic triterpenoid methyl-2-cyano-3,12-dioxooleana-1,9-dien-28-oate (CDDO-Me) has been shown to inhibit AKT, MEK-1/2, and NF-κB, and to induce caspase-mediated apoptosis, we tested the therapeutic potential of this agent in murine lupus nephritis. METHODS The synthetic triterpenoid CDDO-Me or placebo was administered to 2-month-old B6.Sle1.Sle3 mice or MRL/lpr mice, which develop spontaneous lupus. All mice were phenotyped for disease. RESULTS CDDO-Me-treated mice exhibited significantly reduced splenic cellularity, with decreased numbers of both CD4+ T cells and activated CD69+/CD4+ T cells compared to the placebo-treated mice. These mice also exhibited a significant reduction in serum autoantibody levels, including anti-double-stranded DNA (anti-dsDNA) and antiglomerular antibodies. Finally, CDDO-Me treatment attenuated renal disease in mice, as indicated by reduced 24-hour proteinuria, blood urea nitrogen, and glomerulonephritis. At the mechanistic level, CDDO-Me treatment dampened MEK-1/2, ERK, and STAT-3 signaling within lymphocytes and oxidative stress. Importantly, the NF-E2-related factor 2 pathway was activated after CDDO-Me treatment, indicating that CDDO-Me may modulate renal damage in lupus via the inhibition of oxidative stress. CONCLUSION These findings underscore the importance of AKT/MEK-1/2/NF-κB signaling in engendering murine lupus. Our findings indicate that the blockade of multiple signaling nodes and oxidative stress may effectively prevent and reverse the hematologic, autoimmune, and pathologic manifestations of lupus.
Collapse
Affiliation(s)
- Tianfu Wu
- University of Texas Southwestern Medical Center at Dallas and University of Houston, Houston, Texas
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
81
|
Plum LM, Brieger A, Engelhardt G, Hebel S, Nessel A, Arlt M, Kaltenberg J, Schwaneberg U, Huber M, Rink L, Haase H. PTEN-inhibition by zinc ions augments interleukin-2-mediated Akt phosphorylation. Metallomics 2015; 6:1277-87. [PMID: 24759986 DOI: 10.1039/c3mt00197k] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Free zinc ions (Zn(2+)) participate in several signaling pathways. The aim of the present study was to investigate a potential involvement of Zn(2+) in the PI3K/Akt pathway of interleukin (IL)-2 signaling in T-cells. The IL-2 receptor triggers three major pathways, ERK1/2, JAK/STAT5, and PI3K/Akt. We have previously shown that an IL-2-mediated release of lysosomal Zn(2+) into the cytoplasm activates ERK1/2, but not STAT5. In the present study, Akt phosphorylation in response to IL-2 was abrogated by the Zn(2+) chelator N,N,N',N'-tetrakis-2(pyridyl-methyl)ethylenediamine, and was induced by treatment with Zn(2+) and the ionophore pyrithione. The latter were ineffective in cells that were treated with siRNA against the phosphatase and tensin homolog deleted on chromosome 10 (PTEN), a phosphatase that degrades the lipid second messenger PI(3,4,5)P3, which is produced by PI3K and leads to activation of Akt. Inhibition of recombinant PTEN by Zn(2+)in vitro yielded an IC50 of 0.59 nM. Considering a resting free cytoplasmic Zn(2+) level of 0.2 nM in the T-cell line CTLL-2, this seems ideally suited for dynamic regulation by cellular Zn(2+). Oxidation with H2O2 and supplementation with Zn(2+) led to similar changes in the CD spectrum of PTEN. Moreover, Zn(2+) partially prevented the oxidation of cysteines 71 and 124. Hence, we hypothesize that zinc signals affect the IL-2-dependent PI3K/Akt pathway by inhibiting the negative regulator PTEN through binding with a sub-nanomolar affinity to cysteine residues that are essential for its catalytic activity.
Collapse
Affiliation(s)
- Laura Marie Plum
- Institute of Immunology, Medical Faculty, RWTH Aachen University, Pauwelsstrasse 30, 52074 Aachen, Germany.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
82
|
A precisely substituted benzopyran targets androgen refractory prostate cancer cells through selective modulation of estrogen receptors. Toxicol Appl Pharmacol 2015; 283:187-97. [PMID: 25655200 DOI: 10.1016/j.taap.2015.01.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 01/21/2015] [Accepted: 01/23/2015] [Indexed: 12/28/2022]
Abstract
Dietary consumption of phytoestrogens like genistein has been linked with lower incidence of prostate cancer. The estradiol-like benzopyran core of genistein confers estrogen receptor-β (ER-β) selectivity that imparts weak anti-proliferative activity against prostate cancer cells. DL-2-[4-(2-piperidinoethoxy)phenyl]-3-phenyl-2H-1-benzopyran (BP), a SERM designed with benzopyran core, targeted androgen independent prostate cancer (PC-3) cells 14-times more potently than genistein, ~25% more efficiently than tamoxifen and 6.5-times more actively than ICI-182780, without forfeiting significant specificity in comparison to genistein. BP increased apoptosis (annexin-V and TUNEL labeling), arrested cell cycle, and significantly increased caspase-3 activity along with mRNA expressions of estrogen receptor (ER)-β and FasL (qPCR) in PC-3 cells. In classical ERE-luc reporter assay BP behaved as a potent ER-α antagonist and ER-β agonist. Accordingly, it decreased expression of ER-α target PS2 (P<0.01) and increased expression of ER-β target TNF-α (P<0.05) genes in PC-3. ER-β deficient PC-3 (siRNA-transfected) was resistant to apoptotic and anti-proliferative actions of SERMs, including stimulation of FasL expression by BP. BP significantly inhibited phosphorylation of Akt and ERK-1/2, JNK and p38 in PC-3 (immunoblotting), and thus adopted a multi-pathway mechanism to exert a more potent anti-proliferative activity against prostate cancer cells than natural and synthetic SERMs. Its precise ER-subtype specific activity presents a unique lead structure for further optimization.
Collapse
|
83
|
Huynh A, DuPage M, Priyadharshini B, Sage PT, Quiros J, Borges CM, Townamchai N, Gerriets VA, Rathmell JC, Sharpe AH, Bluestone JA, Turka LA. Control of PI(3) kinase in Treg cells maintains homeostasis and lineage stability. Nat Immunol 2015; 16:188-96. [PMID: 25559257 PMCID: PMC4297515 DOI: 10.1038/ni.3077] [Citation(s) in RCA: 319] [Impact Index Per Article: 35.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 12/01/2014] [Indexed: 12/13/2022]
Abstract
Foxp3(+) regulatory T cells (Treg cells) are required for immunological homeostasis. One notable distinction between conventional T cells (Tconv cells) and Treg cells is differences in the activity of phosphatidylinositol-3-OH kinase (PI(3)K); only Tconv cells downregulate PTEN, the main negative regulator of PI(3)K, upon activation. Here we found that control of PI(3)K in Treg cells was essential for lineage homeostasis and stability. Mice lacking Pten in Treg cells developed an autoimmune-lymphoproliferative disease characterized by excessive T helper type 1 (TH1) responses and B cell activation. Diminished control of PI(3)K activity in Treg cells led to reduced expression of the interleukin-2 (IL-2) receptor α subunit CD25, accumulation of Foxp3(+)CD25(-) cells and, ultimately, loss of expression of the transcription factor Foxp3 in these cells. Collectively, our data demonstrate that control of PI(3)K signaling by PTEN in Treg cells is critical for maintaining their homeostasis, function and stability.
Collapse
Affiliation(s)
- Alexandria Huynh
- Division of Medical Sciences, Harvard Medical School, Boston, MA
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Boston, MA
| | - Michel DuPage
- Diabetes Center and the Department of Medicine, University of California - San Francisco, San Francisco, CA
| | - Bhavana Priyadharshini
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Boston, MA
| | - Peter T. Sage
- Division of Immunology, Department of Microbiology, Harvard Medical School, Boston, MA
| | - Jason Quiros
- Diabetes Center and the Department of Medicine, University of California - San Francisco, San Francisco, CA
| | - Christopher M. Borges
- Division of Medical Sciences, Harvard Medical School, Boston, MA
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Boston, MA
| | - Natavudh Townamchai
- Division of Nephrology, Department of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Valerie A. Gerriets
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC
| | - Jeffrey C. Rathmell
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC
| | - Arlene H. Sharpe
- Division of Immunology, Department of Microbiology, Harvard Medical School, Boston, MA
| | - Jeffrey A. Bluestone
- Diabetes Center and the Department of Medicine, University of California - San Francisco, San Francisco, CA
| | - Laurence A. Turka
- Division of Medical Sciences, Harvard Medical School, Boston, MA
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Boston, MA
| |
Collapse
|
84
|
Daikh DI. Animal models of lupus. Rheumatology (Oxford) 2015. [DOI: 10.1016/b978-0-323-09138-1.00129-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
|
85
|
Abstract
Mice with T-cell-specific loss of the tumor suppressor gene PTEN early in T-cell ontogeny develop thymic lymphomas that invariably harbor a reciprocal translocation involving the T-cell receptor α/δ locus and c-myc, t(14;15). In addition to its known function as a lipid phosphatase opposing PI3K signaling, PTEN has also been described as playing a prominent role in promoting genomic stability. As a result, it has been uncertain which one(s) of these 2 separable features were required to block the development of lymphoma. Here, using a conditional model in which T cells selectively express 1 phosphatase-dead PTEN mutant (C124S) and maintain 1 null allele, we show that PTEN phosphatase activity is required for preventing the emergence of a malignant T-cell population harboring t(14;15), thus constituting a critical function of PTEN in preventing lymphomagenesis.
Collapse
|
86
|
A microRNA upregulated in asthma airway T cells promotes TH2 cytokine production. Nat Immunol 2014; 15:1162-70. [PMID: 25362490 PMCID: PMC4233009 DOI: 10.1038/ni.3026] [Citation(s) in RCA: 187] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 10/02/2014] [Indexed: 12/12/2022]
Abstract
MicroRNAs (miRNAs) exert powerful effects on immunological function by tuning networks of target genes that orchestrate cell activity. We sought to identify miRNAs and miRNA-regulated pathways that control the type 2 helper T cell (TH2 cell) responses that drive pathogenic inflammation in asthma. Profiling miRNA expression in human airway-infiltrating T cells revealed elevated expression of the miRNA miR-19a in asthma. Modulating miR-19 activity altered TH2 cytokine production in both human and mouse T cells, and TH2 cell responses were markedly impaired in cells lacking the entire miR-17∼92 cluster. miR-19 promoted TH2 cytokine production and amplified inflammatory signaling by direct targeting of the inositol phosphatase PTEN, the signaling inhibitor SOCS1 and the deubiquitinase A20. Thus, upregulation of miR-19a in asthma may be an indicator and a cause of increased TH2 cytokine production in the airways.
Collapse
|
87
|
Papa A, Wan L, Bonora M, Salmena L, Song MS, Hobbs RM, Lunardi A, Webster K, Ng C, Newton RH, Knoblauch N, Guarnerio J, Ito K, Turka LA, Beck AH, Pinton P, Bronson RT, Wei W, Pandolfi PP. Cancer-associated PTEN mutants act in a dominant-negative manner to suppress PTEN protein function. Cell 2014; 157:595-610. [PMID: 24766807 DOI: 10.1016/j.cell.2014.03.027] [Citation(s) in RCA: 215] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 11/25/2013] [Accepted: 03/11/2014] [Indexed: 10/25/2022]
Abstract
PTEN dysfunction plays a crucial role in the pathogenesis of hereditary and sporadic cancers. Here, we show that PTEN homodimerizes and, in this active conformation, exerts lipid phosphatase activity on PtdIns(3,4,5)P3. We demonstrate that catalytically inactive cancer-associated PTEN mutants heterodimerize with wild-type PTEN and constrain its phosphatase activity in a dominant-negative manner. To study the consequences of homo- and heterodimerization of wild-type and mutant PTEN in vivo, we generated Pten knockin mice harboring two cancer-associated PTEN mutations (PtenC124S and PtenG129E). Heterozygous Pten(C124S/+) and Pten(G129E/+) cells and tissues exhibit increased sensitivity to PI3-K/Akt activation compared to wild-type and Pten(+/-) counterparts, whereas this difference is no longer apparent between Pten(C124S/-) and Pten(-/-) cells. Notably, Pten KI mice are more tumor prone and display features reminiscent of complete Pten loss. Our findings reveal that PTEN loss and PTEN mutations are not synonymous and define a working model for the function and regulation of PTEN.
Collapse
Affiliation(s)
- Antonella Papa
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Department of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Lixin Wan
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Massimo Bonora
- Department of Morphology, Surgery and Experimental Medicine Section of General Pathology University of Ferrara, Ferrara 44124, Italy
| | - Leonardo Salmena
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Department of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Min Sup Song
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Department of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Robin M Hobbs
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Department of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Andrea Lunardi
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Department of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Kaitlyn Webster
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Department of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Christopher Ng
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Department of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Ryan H Newton
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Nicholas Knoblauch
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Jlenia Guarnerio
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Department of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Keisuke Ito
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Department of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Laurence A Turka
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Andy H Beck
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Paolo Pinton
- Department of Morphology, Surgery and Experimental Medicine Section of General Pathology University of Ferrara, Ferrara 44124, Italy
| | - Roderick T Bronson
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Pier Paolo Pandolfi
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Department of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
| |
Collapse
|
88
|
Suárez-Fueyo A, Rojas JM, Cariaga AE, García E, Steiner BH, Barber DF, Puri KD, Carrera AC. Inhibition of PI3Kδ reduces kidney infiltration by macrophages and ameliorates systemic lupus in the mouse. THE JOURNAL OF IMMUNOLOGY 2014; 193:544-54. [PMID: 24935930 DOI: 10.4049/jimmunol.1400350] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Systemic lupus erythematosus (SLE) is a human chronic inflammatory disease generated and maintained throughout life by autoreactive T and B cells. Class I phosphoinositide 3-kinases (PI3K) are heterodimers composed of a regulatory and a catalytic subunit that catalyze phosphoinositide-3,4,5-P3 formation and regulate cell survival, migration, and division. Activity of the PI3Kδ isoform is enhanced in human SLE patient PBLs. In this study, we analyzed the effect of inhibiting PI3Kδ in MRL/lpr mice, a model of human SLE. We found that PI3Kδ inhibition ameliorated lupus progression. Treatment of these mice with a PI3Kδ inhibitor reduced the excessive numbers of CD4(+) effector/memory cells and B cells. In addition, this treatment reduced serum TNF-α levels and the number of macrophages infiltrating the kidney. Expression of inactive PI3Kδ, but not deletion of the other hematopoietic isoform PI3Kγ, reduced the ability of macrophages to cross the basement membrane, a process required to infiltrate the kidney, explaining MRL/lpr mice improvement by pharmacologic inhibition of PI3Kδ. The observations that p110δ inhibitor prolonged mouse life span, reduced disease symptoms, and showed no obvious secondary effects indicates that PI3Kδ is a promising target for SLE.
Collapse
Affiliation(s)
- Abel Suárez-Fueyo
- Departamento de Inmunología y Oncología, Centro Nacional de Biotecnología/Consejo Superior de Investigaciones Científicas, Cantoblanco, Madrid 28049, Spain
| | - José M Rojas
- Departamento de Inmunología y Oncología, Centro Nacional de Biotecnología/Consejo Superior de Investigaciones Científicas, Cantoblanco, Madrid 28049, Spain
| | - Ariel E Cariaga
- Departamento de Inmunología y Oncología, Centro Nacional de Biotecnología/Consejo Superior de Investigaciones Científicas, Cantoblanco, Madrid 28049, Spain
| | - Esther García
- Departamento de Biologia Molecular e Celular, Centro Nacional de Biotecnología/Consejo Superior de Investigaciones Científicas, Cantoblanco, Madrid 28049, Spain; and
| | - Bart H Steiner
- Department of Biology, Gilead Sciences, Seattle, WA 98102
| | - Domingo F Barber
- Departamento de Inmunología y Oncología, Centro Nacional de Biotecnología/Consejo Superior de Investigaciones Científicas, Cantoblanco, Madrid 28049, Spain
| | - Kamal D Puri
- Department of Biology, Gilead Sciences, Seattle, WA 98102
| | - Ana C Carrera
- Departamento de Inmunología y Oncología, Centro Nacional de Biotecnología/Consejo Superior de Investigaciones Científicas, Cantoblanco, Madrid 28049, Spain;
| |
Collapse
|
89
|
Qi X, Xu J, Gu P, Yang X, Gao X. PTEN in smooth muscle cells is essential for colonic immune homeostasis. Int J Biochem Cell Biol 2014; 53:108-14. [PMID: 24819541 DOI: 10.1016/j.biocel.2014.04.029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 04/14/2014] [Accepted: 04/29/2014] [Indexed: 12/25/2022]
Abstract
Colonic immune homeostasis is essential for normal gastrointestinal tract functioning. In this study, we report that specific gene targeting of phosphatase and tensin homolog (PTEN) in smooth muscle cells caused age-related colonic lymphoid hyperplasia followed by global immune activation in mice. Beginning at 5 weeks of age, these mutant mice displayed massive neutrophil infiltration in the colonic lamina propria. The gene expression levels of pro-inflammatory cytokines and chemokines, including those code for monocyte chemotactic protein-1 (Mcp-1), stromal cell-derived factor 1α (Sdf-1α), and chemokine (C-C motif) ligand 28 (Ccl-28), were upregulated in the colon. Accordingly, permeability and proliferation of the colonic epithelium was compromised. These abnormalities were alleviated to a great extent when the mutants were crossed with Akt1-null mice, indicating that the pathogenesis was mediated by Akt1 signaling. Our results suggest that in smooth muscle cells, PTEN is crucial for maintaining colonic immune homeostasis.
Collapse
Affiliation(s)
- Xin Qi
- Genetic Laboratory of Development and Diseases, Institute of Biotechnology, Beijing 100071, PR China; MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, 12 Xuefu Road, Nanjing 210061, China
| | - Jingyue Xu
- Genetic Laboratory of Development and Diseases, Institute of Biotechnology, Beijing 100071, PR China
| | - Pengyu Gu
- Genetic Laboratory of Development and Diseases, Institute of Biotechnology, Beijing 100071, PR China
| | - Xiao Yang
- Genetic Laboratory of Development and Diseases, Institute of Biotechnology, Beijing 100071, PR China
| | - Xiang Gao
- MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, 12 Xuefu Road, Nanjing 210061, China.
| |
Collapse
|
90
|
Sankhala RS, Lokareddy RK, Cingolani G. Structure of human PIR1, an atypical dual-specificity phosphatase. Biochemistry 2014; 53:862-71. [PMID: 24447265 PMCID: PMC3985963 DOI: 10.1021/bi401240x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
![]()
PIR1 is an atypical dual-specificity
phosphatase (DSP) that dephosphorylates
RNA with a higher specificity than phosphoproteins. Here we report
the atomic structure of a catalytically inactive mutant (C152S) of
the human PIR1 phosphatase core (PIR1-core, residues 29–205),
refined at 1.20 Å resolution. PIR1-core shares structural similarities
with DSPs related to Vaccinia virus VH1 and with
RNA 5′-phosphatases such as the baculovirus RNA triphosphatase
and the human mRNA capping enzyme. The PIR1 active site cleft is wider
and deeper than that of VH1 and contains two bound ions: a phosphate
trapped above the catalytic cysteine C152 exemplifies the binding
mode expected for the γ-phosphate of RNA, and ∼6 Å
away, a chloride ion coordinates the general base R158. Two residues
in the PIR1 phosphate-binding loop (P-loop), a histidine (H154) downstream
of C152 and an asparagine (N157) preceding R158, make close contacts
with the active site phosphate, and their nonaliphatic side chains
are essential for phosphatase activity in vitro.
These residues are conserved in all RNA 5′-phosphatases that,
analogous to PIR1, lack a “general acid” residue. Thus,
a deep active site crevice, two active site ions, and conserved P-loop
residues stabilizing the γ-phosphate of RNA are defining features
of atypical DSPs that specialize in dephosphorylating 5′-RNA.
Collapse
Affiliation(s)
- Rajeshwer Singh Sankhala
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University , 233 South 10th Street, Philadelphia, Pennsylvania 19107, United States
| | | | | |
Collapse
|
91
|
PTEN, Longevity and Age-Related Diseases. Biomedicines 2013; 1:17-48. [PMID: 28548055 PMCID: PMC5423463 DOI: 10.3390/biomedicines1010017] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 11/26/2013] [Accepted: 12/09/2013] [Indexed: 02/08/2023] Open
Abstract
Since the discovery of PTEN, this protein has been shown to be an effective suppressor of cancer and a contributor to longevity. This report will review, in depth, the associations between PTEN and other molecules, its mutations and regulations in order to present how PTEN can be used to increase longevity. This report will collect recent research of PTEN and use this to discuss PTEN’s role in caloric restriction, antioxidative defense of DNA-damage and the role it plays in suppressing tumors. The report will also discuss that variety of ways that PTEN can be compromised, through mutations, complete loss of alleles and its main antagonist, the PI3K/AKT pathway.
Collapse
|
92
|
The deubiquitylase Ataxin-3 restricts PTEN transcription in lung cancer cells. Oncogene 2013; 33:4265-72. [PMID: 24292675 PMCID: PMC4351423 DOI: 10.1038/onc.2013.512] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Revised: 10/22/2013] [Accepted: 10/23/2013] [Indexed: 12/12/2022]
Abstract
The phosphatidylinositol-3-kinase (PI3K) pathway is commonly hyperactivated in cancer. One mechanism by which this occurs is by silencing of the phosphatase and tensin homolog (PTEN), a tumor suppressor and major antagonist of the pathway, through genetic, epigenetic or posttranscriptional mechanisms. Here, we used an unbiased siRNA screen in non-small-cell lung cancer cells to identify deubiquitylases (DUBs) that have an impact on PI3K signaling by regulating the abundance of PTEN. We found that PTEN expression was induced by depleting any of three members of the Josephin family DUBs: ataxin 3 (ATXN3), ataxin 3-like (ATXN3L) and Josephin domain containing 1 (JOSD1). However, this effect is not mediated through altered PTEN protein stability. Instead, depletion of each DUB increases expression of both the PTEN transcript and its competing endogenous RNA, PTENP1. In ATXN3-depleted cells, under conditions of transcriptional inhibition, PTEN and PTENP1 mRNAs rapidly decay, suggesting that ATXN3 acts primarily by repressing their transcription. Importantly, the PTEN induction observed in response to ATXN3 siRNA is sufficient to downregulate Akt phosphorylation and hence PI3K signaling. Histone deacetylase inhibitors (HDACi) have been suggested as potential mediators of PTEN transcriptional reactivation in non-small-cell lung cancer. Although PTEN exhibits a very limited response to the broad-spectrum HDACi Vorinostat (SAHA) in A549 cells, we find that combination with ATXN3 depletion enhances PTEN induction in an additive manner. Similarly, these interventions additively decrease cell viability. Thus, ATXN3 provides an autonomous, complementary therapeutic target in cancers with epigenetic downregulation of PTEN.
Collapse
|
93
|
Srivastava N, Sudan R, Kerr WG. Role of inositol poly-phosphatases and their targets in T cell biology. Front Immunol 2013; 4:288. [PMID: 24069021 PMCID: PMC3779868 DOI: 10.3389/fimmu.2013.00288] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Accepted: 09/03/2013] [Indexed: 11/13/2022] Open
Abstract
T lymphocytes play a critical role in host defense in all anatomical sites including mucosal surfaces. This not only includes the effector arm of the immune system, but also regulation of immune responses in order to prevent autoimmunity. Genetic targeting of PI3K isoforms suggests that generation of PI(3,4,5)P3 by PI3K plays a critical role in promoting effector T cell responses. Consequently, the 5'- and 3'-inositol poly-phosphatases SHIP1, SHIP2, and phosphatase and tensin homolog capable of targeting PI(3,4,5)P3 are potential genetic determinants of T cell effector functions in vivo. In addition, the 5'-inositol poly-phosphatases SHIP1 and 2 can shunt PI(3,4,5)P3 to the rare but potent signaling phosphoinositide species PI(3,4)P2 and thus these SHIP1/2, and the INPP4A/B enzymes that deplete PI(3,4)P2 may have precise roles in T cell biology to amplify or inhibit effectors of PI3K signaling that are selectively recruited to and activated by PI(3,4)P2. Here we summarize recent genetic and chemical evidence that indicates the inositol poly-phosphatases have important roles in both the effector and regulatory functions of the T cell compartment. In addition, we will discuss future genetic studies that might be undertaken to further elaborate the role of these enzymes in T cell biology as well as potential pharmaceutical manipulation of these enzymes for therapeutic purposes in disease settings where T cell function is a key in vivo target.
Collapse
Affiliation(s)
- Neetu Srivastava
- Department of Microbiology and Immunology, SUNY Upstate Medical University , Syracuse, NY , USA
| | | | | |
Collapse
|
94
|
Jeker LT, Bour-Jordan H, Bluestone JA. Breakdown in peripheral tolerance in type 1 diabetes in mice and humans. Cold Spring Harb Perspect Med 2013; 2:a007807. [PMID: 22393537 DOI: 10.1101/cshperspect.a007807] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Type 1 Diabetes (T1D), also called juvenile diabetes because of its classically early onset, is considered an autoimmune disease targeting the insulin-producing β cells in the pancreatic islets of Langerhans. T1D reflects a loss of tolerance to tissue self-antigens caused by defects in both central tolerance, which aims at eliminating potentially autoreactive lymphocytes developing in the thymus, and peripheral tolerance, which normally controls autoreactive T cells that escaped the thymus. Like in other autoimmune diseases, the mechanisms leading to T1D are multifactorial and depend on a complex combination of genetic, epigenetic, molecular, and cellular elements that result in the breakdown of peripheral tolerance. In this article, we discuss the contribution of these factors in the development of the autoimmune response targeting pancreatic islets in T1D and the therapeutic strategies currently being explored to correct these defects.
Collapse
Affiliation(s)
- Lukas T Jeker
- UCSF Diabetes Center, University of California at San Francisco, San Francisco, California 94143, USA
| | | | | |
Collapse
|
95
|
Taher TE, Muhammad HA, Rahim A, Flores-Borja F, Renaudineau Y, Isenberg DA, Mageed RA. Aberrant B-lymphocyte responses in lupus: inherent or induced and potential therapeutic targets. Eur J Clin Invest 2013; 43:866-80. [PMID: 23701475 DOI: 10.1111/eci.12111] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 04/29/2013] [Indexed: 12/11/2022]
Abstract
BACKGROUND Lupus is a prototype autoimmune disease of unknown aetiology. The disease is complex; manifest diverse clinical symptoms and disease mechanisms. This complexity has provided many leads to explore: from disease mechanisms to approaches for therapy. B-lymphocytes play a central role in the pathogenesis of the disease. However, the cause of aberrant B-lymphocyte responses in patients and, indeed, its causal relationship with the disease remain unclear. DESIGN This article provides a synopsis of current knowledge of immunological abnormalities in lupus with an emphasis on abnormalities in the B-lymphocyte compartment. RESULTS There is evidence for abnormalities in most compartments of the immune system in animal models and patients with lupus including an ever expanding list of abnormalities within the B-lymphocyte compartment. In addition, recent genome-wide linkage analyses in large cohorts of patients have identified new sets of genetic association factors some with potential links with defective B-lymphocyte responses although their full pathophysiological effects remain to be determined. The accumulating knowledge may help in the identification and application of new targeted therapies for treating lupus disease. CONCLUSIONS Cellular, molecular and genetic studies have provided significant insights into potential causes of immunological defects associated with lupus. Most of this insight relate to defects in B- and T-lymphocyte tolerance, signalling and responses. For B-lymphocytes, there is evidence for altered regulation of inter and intracellular signalling pathways at multiple levels. Some of these abnormalities will be discussed within the context of potential implications for disease pathogenesis and targeted therapies.
Collapse
Affiliation(s)
- Taher E Taher
- Bone & Joint Research Unit, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | | | | | | | | | | | | |
Collapse
|
96
|
Inoue K, Fry EA, Taneja P. Recent progress in mouse models for tumor suppressor genes and its implications in human cancer. Clin Med Insights Oncol 2013; 7:103-22. [PMID: 23843721 PMCID: PMC3682694 DOI: 10.4137/cmo.s10358] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Gain-of-function mutations in oncogenes and loss-of-function mutations in tumor suppressor genes (TSG) lead to cancer. In most human cancers, these mutations occur in somatic tissues. However, hereditary forms of cancer exist for which individuals are heterozygous for a germline mutation in a TSG locus at birth. The second allele is frequently inactivated by gene deletion, point mutation, or promoter methylation in classical TSGs that meet Knudson's two-hit hypothesis. Conversely, the second allele remains as wild-type, even in tumors in which the gene is haplo-insufficient for tumor suppression. This article highlights the importance of PTEN, APC, and other tumor suppressors for counteracting aberrant PI3K, β-catenin, and other oncogenic signaling pathways. We discuss the use of gene-engineered mouse models (GEMM) of human cancer focusing on Pten and Apc knockout mice that recapitulate key genetic events involved in initiation and progression of human neoplasia. Finally, the therapeutic potential of targeting these tumor suppressor and oncogene signaling networks is discussed.
Collapse
Affiliation(s)
- Kazushi Inoue
- Department of Pathology, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157, USA
- Department of Cancer Biology, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157, USA
| | - Elizabeth A. Fry
- Department of Pathology, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157, USA
- Department of Cancer Biology, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157, USA
| | - Pankaj Taneja
- Department of Pathology, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157, USA
- Department of Cancer Biology, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157, USA
| |
Collapse
|
97
|
Guo H, Qiao G, Ying H, Li Z, Zhao Y, Liang Y, Yang L, Lipkowitz S, Penninger JM, Langdon WY, Zhang J. E3 ubiquitin ligase Cbl-b regulates Pten via Nedd4 in T cells independently of its ubiquitin ligase activity. Cell Rep 2013; 1:472-82. [PMID: 22763434 DOI: 10.1016/j.celrep.2012.04.008] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
E3 ubiquitin ligase Cbl-b plays a crucial role in T cell activation and tolerance induction. However, the molecular mechanism by which Cbl-b inhibits T cell activation remains unclear. Here, we report that Cbl-b does not inhibit PI3K but rather suppresses TCR/CD28-induced inactivation of Pten. The elevated Akt activity in Cbl-b(-/-) T cells is therefore due to heightened Pten inactivation. Suppression of Pten inactivation in T cells by Cbl-b is achieved by impeding the association of Pten with Nedd4, which targets Pten K13 for K63-linked polyubiquitination. Consistent with this finding, introducing Nedd4 deficiency into Cbl-b(-/-) mice abrogates hyper-T cell responses caused by the loss of Cbl-b. Hence, our data demonstrate that Cbl-b inhibits T cell activation by suppressing Pten inactivation independently of its ubiquitin ligase activity.
Collapse
Affiliation(s)
- Hui Guo
- Section of Nephrology, Department of Medicine, The University of Chicago, 5841 S. Maryland Avenue, Chicago, IL 60637, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
98
|
Huynh A, Turka LA. Control of T cell tolerance by phosphatase and tensin homolog. Ann N Y Acad Sci 2013; 1280:27-9. [PMID: 23551099 DOI: 10.1111/nyas.12015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The in vivo maintenance of immune tolerance is critically dependent on regulatory T (Treg ) cells, a lineage of CD4(+) T cells expressing the transcription factor Foxp3 that exerts immunoregulatory function. Because of the potential benefit of using Treg cells for cellular immunotherapy in clinical settings, including autoimmune disease and transplantation, much attention has been directed at understanding the signals that govern Treg cell development, function, and homeostasis. Studies with genetically modified mouse models have shown that the lipid phosphatase PTEN (phosphatase and tensin homolog), the predominant negative regulator of the PI3K/Akt pathway in T cells, has multiple functions in sustaining T cell-mediated immune tolerance in vivo. In addition to its role in maintaining T cell homeostasis, the PI3K/Akt pathway also has an essential role in T cell development and lineage commitment, contributing to the cell fate decision between conventional and regulatory T cells.
Collapse
Affiliation(s)
- Alexandria Huynh
- Massachusetts General Hospital, Transplantation Biology Research Center MGH-East, Boston, Massachusetts 02129, USA
| | | |
Collapse
|
99
|
Liu XS, Chopp M, Wang XL, Zhang L, Hozeska-Solgot A, Tang T, Kassis H, Zhang RL, Chen C, Xu J, Zhang ZG. MicroRNA-17-92 cluster mediates the proliferation and survival of neural progenitor cells after stroke. J Biol Chem 2013; 288:12478-88. [PMID: 23511639 DOI: 10.1074/jbc.m112.449025] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The role of microRNAs (miRNAs) in mediating adult neurogenesis after stroke has not been extensively studied. The present study investigated the function of the miR17-92 cluster in adult neural progenitor cells after experimental stroke. We found that stroke substantially up-regulated miR17-92 cluster expression in neural progenitor cells of the adult mouse. Overexpression of the miR17-92 cluster either in cultured ischemic neural progenitor cells or in the subventricular zone (SVZ) of ischemic animals significantly increased cell proliferation, whereas inhibition of individual members of the miR17-92 cluster, miR-18a and miR-19a, suppressed cell proliferation and increased cell death. The miR17-92 cluster mediated PTEN (phosphatase and tensin homolog) expression, which is a predicted target of the miR17-92 cluster. Addition of Sonic hedgehog (Shh) protein up-regulated miR17-92 expression and elevated c-Myc protein in ischemic neural progenitor cells, whereas blockade of the Shh signaling pathway down-regulated miR17-92 cluster expression and reduced c-Myc levels. Overexpression of c-Myc up-regulated miR17-92 cluster expression. Intraventricular infusion of Shh and a Shh receptor inhibitor, cyclopamine, to ischemic animals further elevated and suppressed, respectively, miR17-92 cluster expression in the SVZ. These data indicate that the miR17-92 cluster plays an important role in mediating neural progenitor cell function and that the Shh signaling pathway is involved in up-regulating miR17-92 cluster expression.
Collapse
Affiliation(s)
- Xian Shuang Liu
- Department of Neurology, Henry Ford Health System, Detroit, Michigan 48202, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
100
|
Abstract
Celiac disease (CD)-associated inflammation is characterized by high interleukin- 21 (IL-21), but the mechanisms that control IL-21 production are not fully understood. Here we analyzed IL-21 cell sources and examined how IL-21 production is regulated in CD. Intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs), isolated from CD patients and non-CD controls, were analyzed for cell markers, cytokines, and transcription factors by flow cytometry. IL-21 was highly produced by CD4+ and CD4+/CD8+ IELs and LPLs in active CD. IL-21-producing cells coexpressed interferon-γ (IFN-γ) and to a lesser extent T helper type 17 (Th17) cytokines. Treatment of control LPLs with IL-15, a cytokine overproduced in CD, activated Akt and STAT3 (signal transducer and activator of transcription 3), thus enhancing IL-21 synthesis. Active CD biopsies contained elevated levels of Akt, and blockade of IL-15 in those samples reduced IL-21. Similarly, neutralization of IL-15 in biopsies of inactive CD patients inhibited peptic-tryptic digest of gliadin-induced IL-21 expression. These findings indicate that in CD, IL-15 positively regulates IL-21 production.
Collapse
|