1
|
Duewell BR, Wilson NE, Bailey GM, Peabody SE, Hansen SD. Molecular dissection of PI3Kβ synergistic activation by receptor tyrosine kinases, GβGγ, and Rho-family GTPases. eLife 2024; 12:RP88991. [PMID: 38713746 PMCID: PMC11076043 DOI: 10.7554/elife.88991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2024] Open
Abstract
Phosphoinositide 3-kinase (PI3K) beta (PI3Kβ) is functionally unique in the ability to integrate signals derived from receptor tyrosine kinases (RTKs), G-protein coupled receptors, and Rho-family GTPases. The mechanism by which PI3Kβ prioritizes interactions with various membrane-tethered signaling inputs, however, remains unclear. Previous experiments did not determine whether interactions with membrane-tethered proteins primarily control PI3Kβ localization versus directly modulate lipid kinase activity. To address this gap in our knowledge, we established an assay to directly visualize how three distinct protein interactions regulate PI3Kβ when presented to the kinase in a biologically relevant configuration on supported lipid bilayers. Using single molecule Total Internal Reflection Fluorescence (TIRF) Microscopy, we determined the mechanism controlling PI3Kβ membrane localization, prioritization of signaling inputs, and lipid kinase activation. We find that auto-inhibited PI3Kβ prioritizes interactions with RTK-derived tyrosine phosphorylated (pY) peptides before engaging either GβGγ or Rac1(GTP). Although pY peptides strongly localize PI3Kβ to membranes, stimulation of lipid kinase activity is modest. In the presence of either pY/GβGγ or pY/Rac1(GTP), PI3Kβ activity is dramatically enhanced beyond what can be explained by simply increasing membrane localization. Instead, PI3Kβ is synergistically activated by pY/GβGγ and pY/Rac1 (GTP) through a mechanism consistent with allosteric regulation.
Collapse
Affiliation(s)
- Benjamin R Duewell
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, University of OregonEugeneUnited States
| | - Naomi E Wilson
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, University of OregonEugeneUnited States
| | - Gabriela M Bailey
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, University of OregonEugeneUnited States
| | - Sarah E Peabody
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, University of OregonEugeneUnited States
| | - Scott D Hansen
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, University of OregonEugeneUnited States
| |
Collapse
|
2
|
Duewell BR, Wilson NE, Bailey GM, Peabody SE, Hansen SD. Molecular dissection of PI3Kβ synergistic activation by receptor tyrosine kinases, GβGγ, and Rho-family GTPases. bioRxiv 2023:2023.05.01.538969. [PMID: 37205345 PMCID: PMC10187233 DOI: 10.1101/2023.05.01.538969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The class 1A phosphoinositide 3-kinase (PI3K) beta (PI3Kβ) is functionally unique in the ability to integrate signals derived from receptor tyrosine kinases (RTKs), heterotrimeric guanine nucleotide-binding protein (G-protein)-coupled receptors (GPCRs), and Rho-family GTPases. The mechanism by which PI3Kβ prioritizes interactions with various membrane tethered signaling inputs, however, remains unclear. Previous experiments have not been able to elucidate whether interactions with membrane-tethered proteins primarily control PI3Kβ localization versus directly modulate lipid kinase activity. To address this gap in our understanding of PI3Kβ regulation, we established an assay to directly visualize and decipher how three distinct protein interactions regulate PI3Kβ when presented to the kinase in a biologically relevant configuration on supported lipid bilayers. Using single molecule Total Internal Reflection Fluorescence (TIRF) Microscopy, we determined the mechanism controlling membrane localization of PI3Kβ, prioritization of signaling inputs, and lipid kinase activation. We find that auto-inhibited PI3Kβ prioritizes interactions with RTK-derived tyrosine phosphorylated (pY) peptides before engaging either GβGγ or Rac1(GTP). Although pY peptides strongly localize PI3Kβ to membranes, stimulation of lipid kinase activity is modest. In the presence of either pY/GβGγ or pY/Rac1(GTP), PI3Kβ activity is dramatically enhanced beyond what can be explained by simply increasing the strength of membrane localization. Instead, PI3Kβ is synergistically activated by pY/GβGγ and pY/Rac1(GTP) through a mechanism consistent with allosteric regulation.
Collapse
|
3
|
Safaroghli-Azar A, Sanaei MJ, Pourbagheri-Sigaroodi A, Bashash D. Phosphoinositide 3-kinase (PI3K) classes: From cell signaling to endocytic recycling and autophagy. Eur J Pharmacol 2023:175827. [PMID: 37269974 DOI: 10.1016/j.ejphar.2023.175827] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/19/2023] [Accepted: 05/31/2023] [Indexed: 06/05/2023]
Abstract
Lipid signaling is defined as any biological signaling action in which a lipid messenger binds to a protein target, converting its effects to specific cellular responses. In this complex biological pathway, the family of phosphoinositide 3-kinase (PI3K) represents a pivotal role and affects many aspects of cellular biology from cell survival, proliferation, and migration to endocytosis, intracellular trafficking, metabolism, and autophagy. While yeasts have a single isoform of phosphoinositide 3-kinase (PI3K), mammals possess eight PI3K types divided into three classes. The class I PI3Ks have set the stage to widen research interest in the field of cancer biology. The aberrant activation of class I PI3Ks has been identified in 30-50% of human tumors, and activating mutations in PIK3CA is one of the most frequent oncogenes in human cancer. In addition to indirect participation in cell signaling, class II and III PI3Ks primarily regulate vesicle trafficking. Class III PI3Ks are also responsible for autophagosome formation and autophagy flux. The current review aims to discuss the original data obtained from international research laboratories on the latest discoveries regarding PI3Ks-mediated cell biological processes. Also, we unravel the mechanisms by which pools of the same phosphoinositides (PIs) derived from different PI3K types act differently.
Collapse
Affiliation(s)
- Ava Safaroghli-Azar
- Department of Hematology and Blood Banking, School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad-Javad Sanaei
- Department of Hematology and Blood Banking, School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Atieh Pourbagheri-Sigaroodi
- Department of Hematology and Blood Banking, School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Davood Bashash
- Department of Hematology and Blood Banking, School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
4
|
Buxton AK, Abbasova S, Bevan CL, Leach DA. Liver Microenvironment Response to Prostate Cancer Metastasis and Hormonal Therapy. Cancers (Basel) 2022; 14. [PMID: 36551674 DOI: 10.3390/cancers14246189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/12/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
Prostate cancer-associated deaths arise from disease progression and metastasis. Metastasis to the liver is associated with the worst clinical outcomes for prostate cancer patients, and these metastatic tumors can be particularly resistant to the currently widely used chemotherapy and hormonal therapies, such as anti-androgens which block androgen synthesis or directly target the androgen receptor. The incidence of liver metastases is reportedly increasing, with a potential correlation with use of anti-androgen therapies. A key player in prostate cancer progression and therapeutic response is the microenvironment of the tumor(s). This is a dynamic and adaptive collection of cells and proteins, which impart signals and stimuli that can alter biological processes within prostate cancer cells. Investigation in the prostate primary site has demonstrated that cells of the microenvironment are also responsive to hormones and hormonal therapies. In this review, we collate information about what happens when cancer moves to the liver: the types of prostate cancer cells that metastasize there, the response of resident mesenchymal cells of the liver, and how the interactions between the cancer cells and the microenvironment may be altered by hormonal therapy.
Collapse
|
5
|
Xuan R, Wang J, Zhao X, Li Q, Wang Y, Du S, Duan Q, Guo Y, Ji Z, Chao T. Transcriptome Analysis of Goat Mammary Gland Tissue Reveals the Adaptive Strategies and Molecular Mechanisms of Lactation and Involution. Int J Mol Sci 2022; 23:ijms232214424. [PMID: 36430911 PMCID: PMC9693614 DOI: 10.3390/ijms232214424] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 11/12/2022] [Accepted: 11/16/2022] [Indexed: 11/22/2022] Open
Abstract
To understand how genes precisely regulate lactation physiological activity and the molecular genetic mechanisms underlying mammary gland involution, this study investigated the transcriptome characteristics of goat mammary gland tissues at the late gestation (LG), early lactation (EL), peak lactation (PL), late lactation (LL), dry period (DP), and involution (IN) stages. A total of 13,083 differentially expressed transcripts were identified by mutual comparison of mammary gland tissues at six developmental stages. Genes related to cell growth, apoptosis, immunity, nutrient transport, synthesis, and metabolism make adaptive transcriptional changes to meet the needs of mammary lactation. Notably, platelet derived growth factor receptor beta (PDGFRB) was screened as a hub gene of the mammary gland developmental network, which is highly expressed during the DP and IN. Overexpression of PDGFRB in vitro could slow down the G1/S phase arrest of goat mammary epithelial cell cycle and promote cell proliferation by regulating the PI3K/Akt signaling pathway. In addition, PDGFRB overexpression can also affect the expression of genes related to apoptosis, matrix metalloproteinase family, and vascular development, which is beneficial to the remodeling of mammary gland tissue during involution. These findings provide new insights into the molecular mechanisms involved in lactation and mammary gland involution.
Collapse
|
6
|
Abstract
Over the past two decades, new insights have positioned phosphoinositide 3-kinase-γ (PI3Kγ) as a context-dependent modulator of immunity and inflammation. Recent advances in protein structure determination and drug development have allowed for generation of highly specific PI3Kγ inhibitors, with the first now in clinical trials for several oncology indications. Recently, a monogenic immune disorder caused by PI3Kγ deficiency was discovered in humans and modelled in mice. Human inactivated PI3Kγ syndrome confirms the immunomodulatory roles of PI3Kγ and strengthens newly defined roles of this molecule in modulating inflammatory cytokine release in macrophages. Here, we review the functions of PI3Kγ in the immune system and discuss how our understanding of its potential as a therapeutic target has evolved.
Collapse
Affiliation(s)
- Stephen M Lanahan
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | | | - Carrie L Lucas
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA.
| |
Collapse
|
7
|
Yadav S, Garrido A, Hernández MC, Oliveros JC, Pérez-García V, Fraga MF, Carrera AC. PI3Kβ-regulated β-catenin mediates EZH2 removal from promoters controlling primed human ESC stemness and primitive streak gene expression. Stem Cell Reports 2022; 17:2239-2255. [PMID: 36179694 PMCID: PMC9561645 DOI: 10.1016/j.stemcr.2022.09.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 09/01/2022] [Accepted: 09/02/2022] [Indexed: 11/21/2022] Open
Abstract
The mechanism governing the transition of human embryonic stem cells (hESCs) toward differentiated cells is only partially understood. To explore this transition, the activity and expression of the ubiquitous phosphatidylinositol 3-kinase (PI3Kα and PI3Kβ) were modulated in primed hESCs. The study reports a pathway that dismantles the restraint imposed by the EZH2 polycomb repressor on an essential stemness gene, NODAL, and on transcription factors required to trigger primitive streak formation. The primitive streak is the site where gastrulation begins to give rise to the three embryonic cell layers from which all human tissues derive. The pathway involves a PI3Kβ non-catalytic action that controls nuclear/active RAC1 levels, activation of JNK (Jun N-terminal kinase) and nuclear β-catenin accumulation. β-Catenin deposition at promoters triggers release of the EZH2 repressor, permitting stemness maintenance (through control of NODAL) and correct differentiation by allowing primitive streak master gene expression. PI3Kβ epigenetic control of EZH2/β-catenin might be modulated to direct stem cell differentiation. PI3Kβ directs epigenetic control of stemness and primitive streak (PS) essential genes PI3Kβ directs RAC1/JNK/β-catenin activation and induces EZH2 promoter displacement β-Catenin/EZH2 control NODAL, a gene essential for stemness and the master PS genes PI3Kβ/PI3K activities cooperate at stemness; PI3Kβ directs PS gene expression
Collapse
Affiliation(s)
- Sudhanshu Yadav
- Department of Immunology and Oncology, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Antonio Garrido
- Department of Immunology and Oncology, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - M Carmen Hernández
- Department of Immunology and Oncology, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Juan C Oliveros
- Department of Systems Biology, Bioinformatics, Centro Nacional de Biotecnología/CSIC, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Vicente Pérez-García
- Centro de Investigación Príncipe Felipe, Eduardo Primo Yúfera, 46013 Valencia, Spain
| | - Mario F Fraga
- Nanomaterials and Nanotechnology Research Center/CSIC, Health Research Institute of Asturias (ISPA), Institute of Oncology of Asturias (IUOPA), Research Center for Rare Diseases (CIBERER), 33011 Oviedo, Asturias, Spain
| | - Ana C Carrera
- Department of Immunology and Oncology, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
| |
Collapse
|
8
|
Burgos CF, Cikutovic R, Alarcón M. MicroRNA expression in male infertility. Reprod Fertil Dev 2022; 34:805-818. [PMID: 35760398 DOI: 10.1071/rd21131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Accepted: 05/25/2022] [Indexed: 11/23/2022] Open
Abstract
Male infertility is a multifactorial disorder that involves different physiopathological mechanisms and multiple genes. In this sense, we analyse the role of miRNAs in this pathology. Gene expression analysis can provide relevant information to detect biomarkers, signalling pathways, pathologic mechanisms, and potential therapeutic targets for the disease. In this review, we describe four miRNA microarrays related to patients who present infertility diseases, including azoospermia, asthenozoospermia, and oligoasthenozoospermic. We selected 13 miRNAs with altered expressions in testis tissue (hsa-miR-122-5p, hsa-miR-145-5p, hsa-miR-16-5p, hsa-miR-193a-3p, hsa-miR-19a-3p, hsa-miR-23a-3p, hsa-miR-30b-5p, hsa-miR-34b-5p, hsa-miR-34c-5p, hsa-miR-374b-5p, hsa-miR-449a, hsa-miR-574-3p and hsa-miR-92a-3p), and systematically examine the mechanisms of four relevant miRNAs (hsa-miR-16-5p, hsa-miR-19a-3p, hsa-miR-92a-3p and hsa-miR-30b-5p) which we found that regulated a large number of proteins. An interaction network was generated, and its connections allowed us to identify signalling pathways and interactions between proteins associated with male infertility. In this way, we confirm that the most affected and relevant pathway is the PI3K-Akt signalling.
Collapse
Affiliation(s)
- C F Burgos
- Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción, Concepcion, Chile
| | - R Cikutovic
- Universidad de Talca, Talca, 360000 Maule, Chile
| | - M Alarcón
- Department of Clinical Biochemistry and Immunohaematology, Faculty of Health Sciences, Universidad de Talca, Talca, Chile
| |
Collapse
|
9
|
Morris G, Walder K, Berk M, Carvalho AF, Marx W, Bortolasci CC, Yung AR, Puri BK, Maes M. Intertwined associations between oxidative and nitrosative stress and endocannabinoid system pathways: Relevance for neuropsychiatric disorders. Prog Neuropsychopharmacol Biol Psychiatry 2022; 114:110481. [PMID: 34826557 DOI: 10.1016/j.pnpbp.2021.110481] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 10/19/2021] [Accepted: 11/21/2021] [Indexed: 12/12/2022]
Abstract
The endocannabinoid system (ECS) appears to regulate metabolic, cardiovascular, immune, gastrointestinal, lung, and reproductive system functions, as well as the central nervous system. There is also evidence that neuropsychiatric disorders are associated with ECS abnormalities as well as oxidative and nitrosative stress pathways. The goal of this mechanistic review is to investigate the mechanisms underlying the ECS's regulation of redox signalling, as well as the mechanisms by which activated oxidative and nitrosative stress pathways may impair ECS-mediated signalling. Cannabinoid receptor (CB)1 activation and upregulation of brain CB2 receptors reduce oxidative stress in the brain, resulting in less tissue damage and less neuroinflammation. Chronically high levels of oxidative stress may impair CB1 and CB2 receptor activity. CB1 activation in peripheral cells increases nitrosative stress and inducible nitric oxide (iNOS) activity, reducing mitochondrial activity. Upregulation of CB2 in the peripheral and central nervous systems may reduce iNOS, nitrosative stress, and neuroinflammation. Nitrosative stress may have an impact on CB1 and CB2-mediated signalling. Peripheral immune activation, which frequently occurs in response to nitro-oxidative stress, may result in increased expression of CB2 receptors on T and B lymphocytes, dendritic cells, and macrophages, reducing the production of inflammatory products and limiting the duration and intensity of the immune and oxidative stress response. In conclusion, high levels of oxidative and nitrosative stress may compromise or even abolish ECS-mediated redox pathway regulation. Future research in neuropsychiatric disorders like mood disorders and deficit schizophrenia should explore abnormalities in these intertwined signalling pathways.
Collapse
Affiliation(s)
- Gerwyn Morris
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, School of Medicine, Barwon Health, Geelong, Australia
| | - Ken Walder
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, School of Medicine, Barwon Health, Geelong, Australia.
| | - Michael Berk
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, School of Medicine, Barwon Health, Geelong, Australia; Orygen, Parkville, Victoria, Australia; Centre for Youth Mental Health, The University of Melbourne, Parkville, Victoria, Australia.
| | - Andre F Carvalho
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, School of Medicine, Barwon Health, Geelong, Australia
| | - Wolf Marx
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, School of Medicine, Barwon Health, Geelong, Australia.
| | - Chiara C Bortolasci
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, School of Medicine, Barwon Health, Geelong, Australia.
| | - Alison R Yung
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, School of Medicine, Barwon Health, Geelong, Australia; Orygen, Parkville, Victoria, Australia; Centre for Youth Mental Health, The University of Melbourne, Parkville, Victoria, Australia; School of Health Science, University of Manchester, UK.
| | - Basant K Puri
- University of Winchester, UK, and C.A.R., Cambridge, UK.
| | - Michael Maes
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, School of Medicine, Barwon Health, Geelong, Australia; Department of Psychiatry, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Bangkok, Thailand; Department of Psychiatry, Medical University of Plovdiv, Plovdiv, Bulgaria.
| |
Collapse
|
10
|
Solinas G, Becattini B. PI3K and AKT at the Interface of Signaling and Metabolism. Curr Top Microbiol Immunol 2022. [DOI: 10.1007/978-3-031-06566-8_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
11
|
Aytenfisu TY, Campbell HM, Chakrabarti M, Amzel LM, Gabelli SB. Class I PI3K Biology. Curr Top Microbiol Immunol 2022. [DOI: 10.1007/978-3-031-06566-8_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
12
|
Zhang B, Luk C, Valadares J, Aronis C, Foukas LC. Dominant Role of PI3K p110α over p110β in Insulin and β-Adrenergic Receptor Signalling. Int J Mol Sci 2021; 22:12813. [PMID: 34884613 DOI: 10.3390/ijms222312813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/10/2021] [Accepted: 11/23/2021] [Indexed: 11/17/2022] Open
Abstract
Attribution of specific roles to the two ubiquitously expressed PI 3-kinase (PI3K) isoforms p110α and p110β in biological functions they have been implicated, such as in insulin signalling, has been challenging. While p110α has been demonstrated to be the principal isoform activated downstream of the insulin receptor, several studies have provided evidence for a role of p110β. Here we have used isoform-selective inhibitors to estimate the relative contribution of each of these isoforms in insulin signalling in adipocytes, which are a cell type with essential roles in regulation of metabolism at the systemic level. Consistent with previous genetic and pharmacological studies, we found that p110α is the principal isoform activated downstream of the insulin receptor under physiological conditions. p110α interaction with Ras enhanced the strength of p110α activation by insulin. However, this interaction did not account for the selectivity for p110α over p110β in insulin signalling. We also demonstrate that p110α is the principal isoform activated downstream of the β-adrenergic receptor (β-AR), another important signalling pathway in metabolic regulation, through a mechanism involving activation of the cAMP effector molecule EPAC1. This study offers further insights in the role of PI3K isoforms in the regulation of energy metabolism with implications for the therapeutic application of selective inhibitors of these isoforms.
Collapse
|
13
|
Berta GN, Di Scipio F, Yang Z, Oberto A, Abbadessa G, Romano F, Carere ME, Ceccarelli A, Hirsch E, Mognetti B. Chemical Oral Cancerogenesis Is Impaired in PI3Kγ Knockout and Kinase-Dead Mice. Cancers (Basel) 2021; 13:cancers13164211. [PMID: 34439365 PMCID: PMC8391366 DOI: 10.3390/cancers13164211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 08/17/2021] [Accepted: 08/18/2021] [Indexed: 12/08/2022] Open
Abstract
We investigated the role of PI3Kγ in oral carcinogenesis by using a murine model of oral squamous carcinoma generated by exposure to 4-nitroquinoline 1-oxide (4NQO) and the continuous human cancer cell line HSC-2 and Cal-27. PI3Kγ knockout (not expressing PI3Kγ), PI3Kγ kinase-dead (carrying a mutation in the PI3Kγ gene causing loss of kinase activity) and wild-type (WT) C57Bl/6 mice were administered 4NQO via drinking water to induce oral carcinomas. At sacrifice, lesions were histologically examined and stained for prognostic tumoral markers (EGFR, Neu, cKit, Ki67) and inflammatory infiltrate (CD3, CD4, CD8, CD19 and CD68). Prevalence and incidence of preneoplastic and exophytic lesions were significantly and similarly delayed in both transgenic mice versus the control. The expression of prognostic markers, as well as CD19+ and CD68+ cells, was higher in WT, while T lymphocytes were more abundant in tongues isolated from transgenic mice. HSC-2 and Cal-27 cells were cultured in the presence of the specific PI3Kγ-inhibitor (IPI-549) which significantly impaired cell vitality in a dose-dependent manner, as shown by the MTT test. Here, we highlighted two different mechanisms, namely the modulation of the tumor-infiltrating cells and the direct inhibition of cancer-cell proliferation, which might impair oral cancerogenesis in the absence/inhibition of PI3Kγ.
Collapse
Affiliation(s)
- Giovanni Nicolao Berta
- Department of Clinical and Biological Science, University of Turin, Regione Gonzole 10, 10043 Orbassano, TO, Italy; (F.D.S.); (G.A.); (M.E.C.); (A.C.)
- Correspondence: (G.N.B.); (B.M.); Tel.: +39-011-670-5446 (G.N.B.); +39-011-670-4518 (B.M.)
| | - Federica Di Scipio
- Department of Clinical and Biological Science, University of Turin, Regione Gonzole 10, 10043 Orbassano, TO, Italy; (F.D.S.); (G.A.); (M.E.C.); (A.C.)
| | - Zhiqian Yang
- Scientific Research Center, First Affiliated Hospital of Guangdong Pharmaceutical University, No. 19 Nonglinxia Road, Guangzhou 510080, China;
| | - Alessandra Oberto
- Department of Neuroscience, University of Turin, Regione Gonzole 10, 10043 Orbassano, TO, Italy;
- Neuroscience Institute of the Cavalieri-Ottolenghi Foundation, Regione Gonzole 10, 10043 Orbassano, TO, Italy
| | - Giuliana Abbadessa
- Department of Clinical and Biological Science, University of Turin, Regione Gonzole 10, 10043 Orbassano, TO, Italy; (F.D.S.); (G.A.); (M.E.C.); (A.C.)
| | - Federica Romano
- Department of Surgical Sciences, C.I.R. Dental School, University of Turin, 10126 Turin, Italy;
| | - Maria Elisabetta Carere
- Department of Clinical and Biological Science, University of Turin, Regione Gonzole 10, 10043 Orbassano, TO, Italy; (F.D.S.); (G.A.); (M.E.C.); (A.C.)
| | - Adriano Ceccarelli
- Department of Clinical and Biological Science, University of Turin, Regione Gonzole 10, 10043 Orbassano, TO, Italy; (F.D.S.); (G.A.); (M.E.C.); (A.C.)
- Neuroscience Institute of the Cavalieri-Ottolenghi Foundation, Regione Gonzole 10, 10043 Orbassano, TO, Italy
| | - Emilio Hirsch
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, 10126 Turin, Italy;
| | - Barbara Mognetti
- Department of Life Science and System Biology, University of Turin, Via Accademia Albertina 13, 10123 Turin, Italy
- Correspondence: (G.N.B.); (B.M.); Tel.: +39-011-670-5446 (G.N.B.); +39-011-670-4518 (B.M.)
| |
Collapse
|
14
|
Zhang Y, Chaput C, Fournier E, Prunier J, Sirard MA. Comparing the whole genome methylation landscape of dairy calf blood cells revealed intergenerational inheritance of the maternal metabolism. Epigenetics 2021; 17:705-714. [PMID: 34304691 DOI: 10.1080/15592294.2021.1955188] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
This study evaluated the hypothesis that the maternal metabolic stressed status could be inherited to their F1 daughters via epigenetic mechanism. The maternal cow blood β-hydroxybutyric acid (BHB) level (≥0.9 mM/L) was used as an indicator of maternal metabolic stress. Eight newborn daughters' blood cells were used for methylation comparison and analysis. By Whole Genome Bisulphite Sequencing (WGBS), a total of 1,861 Differentially Methylated Regions (DMRs), including 944 differentially methylated cytosines (DMCs), were identified. Most DMRs were distributed in intronic and intergenic regions, and most of the DMR in promoter regions were hypermethylated. Differentially methylated genes (DMGs) with DMR methylation differences higher than 20% were mainly enriched in metabolism-related pathways. These results suggest that newborn calves' metabolic pathways were altered, with 64 DMGs being clustered with metabolic signalling by KEGG analysis. Our study revealed the whole epigenetic landscape of calf blood cells and suggested that the maternal metabolic status can affect the embryo's epigenetic status and metabolic-related pathways in offspring, providing further evidence for epigenetic intergenerational inheritance of metabolic stress in domestic animals. Besides, this study also contributed more evidence to support the Developmental Origins of Health and Disease (DOHAD) theory in large animals.
Collapse
Affiliation(s)
- Ying Zhang
- Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Faculté des Sciences de l'Agriculture et de l'Alimentation, Département des Sciences Animales, Pavillon INAF, Université Laval, Québec, Québec, Canada
| | - Catherine Chaput
- Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Faculté des Sciences de l'Agriculture et de l'Alimentation, Département des Sciences Animales, Pavillon INAF, Université Laval, Québec, Québec, Canada
| | - Eric Fournier
- Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Faculté des Sciences de l'Agriculture et de l'Alimentation, Département des Sciences Animales, Pavillon INAF, Université Laval, Québec, Québec, Canada
| | - Julien Prunier
- Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Faculté des Sciences de l'Agriculture et de l'Alimentation, Département des Sciences Animales, Pavillon INAF, Université Laval, Québec, Québec, Canada
| | - Marc-André Sirard
- Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Faculté des Sciences de l'Agriculture et de l'Alimentation, Département des Sciences Animales, Pavillon INAF, Université Laval, Québec, Québec, Canada
| |
Collapse
|
15
|
Li H, Prever L, Hirsch E, Gulluni F. Targeting PI3K/AKT/mTOR Signaling Pathway in Breast Cancer. Cancers (Basel) 2021; 13:3517. [PMID: 34298731 PMCID: PMC8304822 DOI: 10.3390/cancers13143517] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/06/2021] [Accepted: 07/10/2021] [Indexed: 12/19/2022] Open
Abstract
Breast cancer is the most frequently diagnosed cancer and the primary cause of cancer death in women worldwide. Although early diagnosis and cancer growth inhibition has significantly improved breast cancer survival rate over the years, there is a current need to develop more effective systemic treatments to prevent metastasis. One of the most commonly altered pathways driving breast cancer cell growth, survival, and motility is the PI3K/AKT/mTOR signaling cascade. In the past 30 years, a great surge of inhibitors targeting these key players has been developed at a rapid pace, leading to effective preclinical studies for cancer therapeutics. However, the central role of PI3K/AKT/mTOR signaling varies among diverse biological processes, suggesting the need for more specific and sophisticated strategies for their use in cancer therapy. In this review, we provide a perspective on the role of the PI3K signaling pathway and the most recently developed PI3K-targeting breast cancer therapies.
Collapse
Affiliation(s)
| | | | | | - Federico Gulluni
- Department of Molecular Biotechnology and Health Sciences, University of Turin, 10126 Turin, Italy; (H.L.); (L.P.); (E.H.)
| |
Collapse
|
16
|
Moradi S, Jarrahi E, Ahmadi A, Salimian J, Karimi M, Zarei A, Azimzadeh Jamalkandi S, Ghanei M. PI3K signalling in chronic obstructive pulmonary disease and opportunities for therapy. J Pathol 2021; 254:505-518. [PMID: 33959951 DOI: 10.1002/path.5696] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 04/01/2021] [Accepted: 04/26/2021] [Indexed: 11/08/2022]
Abstract
Chronic obstructive pulmonary disease (COPD) is a chronic lung disease characterised by airway inflammation and progressive obstruction of the lung airflow. Current pharmacological treatments include bronchodilators, alone or in combination with steroids, or other anti-inflammatory agents, which have only partially contributed to the inhibition of disease progression and mortality. Therefore, further research unravelling the underlying mechanisms is necessary to develop new anti-COPD drugs with both lower toxicity and higher efficacy. Extrinsic signalling pathways play crucial roles in COPD development and exacerbations. In particular, phosphoinositide 3-kinase (PI3K) signalling has recently been shown to be a major driver of the COPD phenotype. Therefore, several small-molecule inhibitors have been identified to block the hyperactivation of this signalling pathway in COPD patients, many of them showing promising outcomes in both preclinical animal models of COPD and human clinical trials. In this review, we discuss the critically important roles played by hyperactivated PI3K signalling in the pathogenesis of COPD. We also critically review current therapeutics based on PI3K inhibition, and provide suggestions focusing on PI3K signalling for the further improvement of the COPD phenotype. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Sharif Moradi
- Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.,Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Esmaeil Jarrahi
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Ali Ahmadi
- Molecular Biology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Jafar Salimian
- Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Mehrdad Karimi
- Department of Traditional Medicine, School of Persian Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Azadeh Zarei
- Department of Traditional Medicine, School of Persian Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Sadegh Azimzadeh Jamalkandi
- Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Mostafa Ghanei
- Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| |
Collapse
|
17
|
Arcucci S, Ramos-delgado F, Cayron C, Therville N, Gratacap M, Basset C, Thibault B, Guillermet-guibert J. Organismal roles for the PI3Kα and β isoforms: their specificity, redundancy or cooperation is context-dependent. Biochem J 2021; 478:1199-225. [DOI: 10.1042/bcj20210004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/16/2021] [Accepted: 02/22/2021] [Indexed: 02/07/2023]
Abstract
PI3Ks are important lipid kinases that produce phosphoinositides phosphorylated in position 3 of the inositol ring. There are three classes of PI3Ks: class I PI3Ks produce PIP3 at plasma membrane level. Although D. melanogaster and C. elegans have only one form of class I PI3K, vertebrates have four class I PI3Ks called isoforms despite being encoded by four different genes. Hence, duplication of these genes coincides with the acquisition of coordinated multi-organ development. Of the class I PI3Ks, PI3Kα and PI3Kβ, encoded by PIK3CA and PIK3CB, are ubiquitously expressed. They present similar putative protein domains and share PI(4,5)P2 lipid substrate specificity. Fifteen years after publication of their first isoform-selective pharmacological inhibitors and genetically engineered mouse models (GEMMs) that mimic their complete and specific pharmacological inhibition, we review the knowledge gathered in relation to the redundant and selective roles of PI3Kα and PI3Kβ. Recent data suggest that, further to their redundancy, they cooperate for the integration of organ-specific and context-specific signal cues, to orchestrate organ development, physiology, and disease. This knowledge reinforces the importance of isoform-selective inhibitors in clinical settings.
Collapse
|
18
|
Abstract
Phosphatidyl inositol 3 kinase gamma (PI3Kγ) is expressed in all the cell types that are involved in airway inflammation and disease, including not only leukocytes, but also structural cells, where it is expressed at very low levels under physiological conditions, while is significantly upregulated after stress. In the airways, PI3Kγ behaves as a trigger or a controller, depending on the pathological context. In this review, the contribution of PI3Kγ in a plethora of respiratory diseases, spanning from acute lung injury, pulmonary fibrosis, asthma, cystic fibrosis and response to both bacterial and viral pathogens, will be commented.
Collapse
Affiliation(s)
- Valentina Sala
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, 10126, Torino, Italy
| | - Angela Della Sala
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, 10126, Torino, Italy
| | - Alessandra Ghigo
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, 10126, Torino, Italy.,Kither Biotech S.r.l. Via Nizza 52, 10126, Torino, Italy.,Equal contribution to senior authorship
| | - Emilio Hirsch
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, 10126, Torino, Italy.,Kither Biotech S.r.l. Via Nizza 52, 10126, Torino, Italy.,Equal contribution to senior authorship
| |
Collapse
|
19
|
Gjelaj E, Hamel PA. Distinct epithelial-to-mesenchymal transitions induced by PIK3CA H1047R and PIK3CB. J Cell Sci 2021; 134:jcs.248294. [PMID: 33526718 DOI: 10.1242/jcs.248294] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 01/13/2021] [Indexed: 02/01/2023] Open
Abstract
The most common PIK3CA mutation, producing the H1047R mutant of p110α, arises in myriad malignancies and is typically observed in low-grade breast tumours. In contrast, amplification is observed for wild-type PIK3CB, encoding p110β, and occurs at low frequency but in aggressive, high-grade metastatic tumours. We hypothesized that mutant p110αH1047R and wild-type p110β give rise to distinct transformed phenotypes. We show that p110αH1047R and wild-type p110β, but not wild-type p110α, transform MCF-10A cells and constitutively stimulate phosphoinositide 3-kinase (PI3K)-AKT pathway signalling. However, their resultant morphological transformed phenotypes are distinct. p110αH1047R induced an epithelial-to-mesenchymal transition (EMT) commensurate with SNAIL (also known as SNAI1) induction and loss of E-cadherin. Upon p110β expression, however, E-cadherin expression was maintained despite cells readily delaminating from epithelial sheets. Distinct from the prominent filopodia in p110αH1047R-expressing cells, p110β induced formation of lamellipodia, and these cells migrated with significantly greater velocity and decreased directionality. p110β-induced phenotypic alterations were accompanied by hyperactivation of RAC1; the dependency of transformation of p110β-binding to Rac1 revealed using a Rac1-binding mutant of p110β. Thus, PIK3CB amplification induces a transformed phenotype that is dependent upon a p110β-Rac1 signalling loop and is distinct from the transformed phenotype induced by p110αH1047R.
Collapse
Affiliation(s)
- Ersa Gjelaj
- Department of Laboratory Medicine & Pathobiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Paul A Hamel
- Department of Laboratory Medicine & Pathobiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| |
Collapse
|
20
|
Mazloumi Gavgani F, Karlsson T, Tangen IL, Morovicz AP, Arnesen VS, Turcu DC, Ninzima S, Spang K, Krakstad C, Guillermet-Guibert J, Lewis AE. Nuclear upregulation of class I phosphoinositide 3-kinase p110β correlates with high 47S rRNA levels in cancer cells. J Cell Sci 2021; 134:jcs.246090. [PMID: 33536247 DOI: 10.1242/jcs.246090] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 12/24/2020] [Indexed: 12/12/2022] Open
Abstract
The class I phosphoinositide 3-kinase (PI3K) catalytic subunits p110α and p110β are ubiquitously expressed but differently targeted in tumours. In cancer, PIK3CB (encoding p110β) is seldom mutated compared with PIK3CA (encoding p110α) but can contribute to tumorigenesis in certain PTEN-deficient tumours. The underlying molecular mechanisms are, however, unclear. We have previously reported that p110β is highly expressed in endometrial cancer (EC) cell lines and at the mRNA level in primary patient tumours. Here, we show that p110β protein levels are high in both the cytoplasmic and nuclear compartments in EC cells. Moreover, high nuclear:cytoplasmic staining ratios were detected in high-grade primary tumours. High levels of phosphatidylinositol (3,4,5)-trisphosphate [PtdIns(3,4,5)P 3] were measured in the nucleus of EC cells, and pharmacological and genetic approaches showed that its production was partly dependent upon p110β activity. Using immunofluorescence staining, p110β and PtdIns(3,4,5)P 3 were localised in the nucleolus, which correlated with high levels of 47S pre-rRNA. p110β inhibition led to a decrease in both 47S rRNA levels and cell proliferation. In conclusion, these results present a nucleolar role for p110β that may contribute to tumorigenesis in EC.This article has an associated First Person interview with Fatemeh Mazloumi Gavgani, joint first author of the paper.
Collapse
Affiliation(s)
| | - Thomas Karlsson
- Department of Biological Sciences, University of Bergen, Bergen 5008, Norway
| | - Ingvild L Tangen
- Centre for Cancer Biomarkers, Department of Clinical Science, University of Bergen, Bergen 5021, Norway.,Department of Gynaecology and Obstetrics, Haukeland University Hospital, Bergen 5021, Norway
| | | | | | - Diana C Turcu
- Department of Biological Sciences, University of Bergen, Bergen 5008, Norway
| | - Sandra Ninzima
- Department of Biological Sciences, University of Bergen, Bergen 5008, Norway
| | - Katharina Spang
- Department of Biological Sciences, University of Bergen, Bergen 5008, Norway
| | - Camilla Krakstad
- Centre for Cancer Biomarkers, Department of Clinical Science, University of Bergen, Bergen 5021, Norway.,Department of Gynaecology and Obstetrics, Haukeland University Hospital, Bergen 5021, Norway
| | - Julie Guillermet-Guibert
- Inserm U1037, Centre de Recherches en Cancérologie de Toulouse (CRCT), Institut National de la Santé et de la Recherche Médicale (INSERM), Université Toulouse III Paul Sabatier, 31037 Toulouse, France
| | - Aurélia E Lewis
- Department of Biological Sciences, University of Bergen, Bergen 5008, Norway
| |
Collapse
|
21
|
Aydin E, Faehling S, Saleh M, Llaó Cid L, Seiffert M, Roessner PM. Phosphoinositide 3-Kinase Signaling in the Tumor Microenvironment: What Do We Need to Consider When Treating Chronic Lymphocytic Leukemia With PI3K Inhibitors? Front Immunol 2021; 11:595818. [PMID: 33552053 PMCID: PMC7857022 DOI: 10.3389/fimmu.2020.595818] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 12/07/2020] [Indexed: 12/12/2022] Open
Abstract
Phosphoinositide 3-kinases (PI3Ks) and their downstream proteins constitute a signaling pathway that is involved in both normal cell growth and malignant transformation of cells. Under physiological conditions, PI3K signaling regulates various cellular functions such as apoptosis, survival, proliferation, and growth, depending on the extracellular signals. A deterioration of these extracellular signals caused by mutational damage in oncogenes or growth factor receptors may result in hyperactivation of this signaling cascade, which is recognized as a hallmark of cancer. Although higher activation of PI3K pathway is common in many types of cancer, it has been therapeutically targeted for the first time in chronic lymphocytic leukemia (CLL), demonstrating its significance in B-cell receptor (BCR) signaling and malignant B-cell expansion. The biological activity of the PI3K pathway is not only limited to cancer cells but is also crucial for many components of the tumor microenvironment, as PI3K signaling regulates cytokine responses, and ensures the development and function of immune cells. Therefore, the success or failure of the PI3K inhibition is strongly related to microenvironmental stimuli. In this review, we outline the impacts of PI3K inhibition on the tumor microenvironment with a specific focus on CLL. Acknowledging the effects of PI3K inhibitor-based therapies on the tumor microenvironment in CLL can serve as a rationale for improved drug development, explain treatment-associated adverse events, and suggest novel combinatory treatment strategies in CLL.
Collapse
Affiliation(s)
- Ebru Aydin
- Molecular Genetics, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Institute of Clinical Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Sebastian Faehling
- Molecular Genetics, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Medical Faculty, University of Heidelberg, Heidelberg, Germany
| | - Mariam Saleh
- Molecular Genetics, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Faculty of Molecular Medicine, Ulm University, Ulm, Germany
| | - Laura Llaó Cid
- Molecular Genetics, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Faculty of Bioscience, University of Heidelberg, Heidelberg, Germany
| | - Martina Seiffert
- Molecular Genetics, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Philipp M Roessner
- Molecular Genetics, German Cancer Research Center (DKFZ), Heidelberg, Germany
| |
Collapse
|
22
|
Brunner JS, Vogel A, Lercher A, Caldera M, Korosec A, Pühringer M, Hofmann M, Hajto A, Kieler M, Garrido LQ, Kerndl M, Kuttke M, Mesteri I, Górna MW, Kulik M, Dominiak PM, Brandon AE, Estevez E, Egan CL, Gruber F, Schweiger M, Menche J, Bergthaler A, Weichhart T, Klavins K, Febbraio MA, Sharif O, Schabbauer G. The PI3K pathway preserves metabolic health through MARCO-dependent lipid uptake by adipose tissue macrophages. Nat Metab 2020; 2:1427-1442. [PMID: 33199895 DOI: 10.1038/s42255-020-00311-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 10/09/2020] [Indexed: 12/25/2022]
Abstract
Adipose tissue macrophages (ATMs) display tremendous heterogeneity depending on signals in their local microenvironment and contribute to the pathogenesis of obesity. The phosphoinositide 3-kinase (PI3K) signalling pathway, antagonized by the phosphatase and tensin homologue (PTEN), is important for metabolic responses to obesity. We hypothesized that fluctuations in macrophage-intrinsic PI3K activity via PTEN could alter the trajectory of metabolic disease by driving distinct ATM populations. Using mice harbouring macrophage-specific PTEN deletion or bone marrow chimeras carrying additional PTEN copies, we demonstrate that sustained PI3K activity in macrophages preserves metabolic health in obesity by preventing lipotoxicity. Myeloid PI3K signalling promotes a beneficial ATM population characterized by lipid uptake, catabolism and high expression of the scavenger macrophage receptor with collagenous structure (MARCO). Dual MARCO and myeloid PTEN deficiencies prevent the generation of lipid-buffering ATMs, reversing the beneficial actions of elevated myeloid PI3K activity in metabolic disease. Thus, macrophage-intrinsic PI3K signalling boosts metabolic health by driving ATM programmes associated with MARCO-dependent lipid uptake.
Collapse
Affiliation(s)
- Julia S Brunner
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Andrea Vogel
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Alexander Lercher
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Michael Caldera
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
- Max Perutz Laboratories, Vienna, Austria
| | - Ana Korosec
- Skin and Endothelium Research Division, Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Marlene Pühringer
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Melanie Hofmann
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Alexander Hajto
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Markus Kieler
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Lucia Quemada Garrido
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Martina Kerndl
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Mario Kuttke
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | | | - Maria W Górna
- Biological and Chemical Research Centre, Department of Chemistry, University of Warsaw, Warsaw, Poland
| | - Marta Kulik
- Biological and Chemical Research Centre, Department of Chemistry, University of Warsaw, Warsaw, Poland
| | - Paulina M Dominiak
- Biological and Chemical Research Centre, Department of Chemistry, University of Warsaw, Warsaw, Poland
| | - Amanda E Brandon
- Insulin Action and Energy Metabolism Laboratory, Division of Diabetes & Metabolism, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
- Faculty of Medicine and Health, School of Medical Sciences, University of Sydney, Sydney, New South Wales, Australia
| | - Emma Estevez
- Cellular & Molecular Metabolism Laboratory, Division of Diabetes & Metabolism, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Casey L Egan
- Cellular & Molecular Metabolism Laboratory, Division of Diabetes & Metabolism, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Florian Gruber
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Martina Schweiger
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Jörg Menche
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
- Max Perutz Laboratories, Vienna, Austria
| | - Andreas Bergthaler
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Thomas Weichhart
- Center of Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, Vienna, Austria
| | - Kristaps Klavins
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
- Rudolfs Cimdins Riga Biomaterials Innovations and Development Centre, Riga Technical University, Riga, Latvia
| | - Mark A Febbraio
- Cellular & Molecular Metabolism Laboratory, Division of Diabetes & Metabolism, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Omar Sharif
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria.
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria.
| | - Gernot Schabbauer
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria.
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria.
| |
Collapse
|
23
|
Xie S, Ni J, McFaline-Figueroa JR, Wang Y, Bronson RT, Ligon KL, Wen PY, Roberts TM, Zhao JJ. Divergent Roles of PI3K Isoforms in PTEN-Deficient Glioblastomas. Cell Rep 2020; 32:108196. [PMID: 32997991 PMCID: PMC7571617 DOI: 10.1016/j.celrep.2020.108196] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 08/10/2020] [Accepted: 09/03/2020] [Indexed: 01/01/2023] Open
Abstract
Loss of PTEN, the negative regulator of PI3K activity, is frequent in glioblastomas (GBMs). However, the role of the two major PI3K isoforms, p110α and p110β, in PTEN-deficient gliomagenesis remains unknown. We show that PTEN-deficient GBM largely depends on p110α for proliferation and p110β for migration. Genetic ablation of either isoform delays tumor progression in mice, but only ablating both isoforms completely blocks GBM driven by the concurrent ablation of Pten and p53. BKM120 (buparlisib) treatment only modestly prolongs survival in mice bearing intracranial Pten/p53 null tumors due to partial pathway inhibition. BKM120 extends the survival of mice bearing intracranial tumors in which p110β, but not p110α, has been genetically ablated in the Pten/p53 null glioma, indicating that BKM120 fails to inhibit p110β effectively. Our study suggests that the failure of PI3K inhibitors in GBM may be due to insufficient inhibition of p110β and indicates a need to develop brain-penetrant p110α/β inhibitors. Xie et al. show that p110α and p110β isoforms of PI3K play overlapping and divergent roles in PTEN-deficient glioblastomas, suggesting the importance of blocking both PI3K isoforms to effectively treat PTEN-deficient glioblastomas. Moreover, this study also provides a potential mechanism explaining the failure of BKM120 in the clinic.
Collapse
Affiliation(s)
- Shaozhen Xie
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02215, USA
| | - Jing Ni
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02215, USA
| | - J Ricardo McFaline-Figueroa
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Center for Neuro-Oncology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Departments of Medical Oncology and Oncologic Pathology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Yanzhi Wang
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Roderick T Bronson
- Dana-Farber/Harvard Cancer Center Rodent Histopathology Core, Boston, MA 02215, USA
| | - Keith L Ligon
- Center for Neuro-Oncology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Departments of Medical Oncology and Oncologic Pathology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Patrick Y Wen
- Center for Neuro-Oncology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Departments of Medical Oncology and Oncologic Pathology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Thomas M Roberts
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02215, USA.
| | - Jean J Zhao
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02215, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA.
| |
Collapse
|
24
|
Zecchin D, Moore C, Michailidis F, Horswell S, Rana S, Howell M, Downward J. Combined targeting of G protein-coupled receptor and EGF receptor signaling overcomes resistance to PI3K pathway inhibitors in PTEN-null triple negative breast cancer. EMBO Mol Med 2020; 12:e11987. [PMID: 32672423 PMCID: PMC7411640 DOI: 10.15252/emmm.202011987] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 06/09/2020] [Accepted: 06/16/2020] [Indexed: 12/12/2022] Open
Abstract
Triple-negative breast cancer (TNBC) has poorer prognosis compared to other types of breast cancers due to the lack of effective therapies and markers for patient stratification. Loss of PTEN tumor suppressor gene expression is a frequent event in TNBC, resulting in over-activation of the PI 3-kinase (PI3K) pathway and sensitivity to its inhibition. However, PI3K pathway inhibitors show limited efficacy as monotherapies on these tumors. We report a whole-genome screen to identify targets whose inhibition enhanced the effects of different PI3K pathway inhibitors on PTEN-null TNBC. This identified a signaling network that relies on both the G protein-coupled receptor for thrombin (PAR1/F2R) and downstream G protein βγ subunits and also epidermal growth factor receptor (EGFR) for the activation of the PI3K isoform p110β and AKT. Compensation mechanisms involving these two branches of the pathway could bypass PI3K blockade, but combination targeting of both EGFR and PI3Kβ suppressed ribosomal protein S6 phosphorylation and exerted anti-tumor activity both in vitro and in vivo, suggesting a new potential therapeutic strategy for PTEN-null TNBC.
Collapse
Affiliation(s)
| | | | | | | | - Sareena Rana
- Oncogene BiologyFrancis Crick InstituteLondonUK
- Lung Cancer GroupInstitute of Cancer ResearchLondonUK
| | - Michael Howell
- High Throughput Screening LaboratoriesFrancis Crick InstituteLondonUK
| | - Julian Downward
- Oncogene BiologyFrancis Crick InstituteLondonUK
- Lung Cancer GroupInstitute of Cancer ResearchLondonUK
| |
Collapse
|
25
|
Hervieu A, Heuss SF, Zhang C, Barrow-McGee R, Joffre C, Ménard L, Clarke PA, Kermorgant S. A PI3K- and GTPase-independent Rac1-mTOR mechanism mediates MET-driven anchorage-independent cell growth but not migration. Sci Signal 2020; 13:eaba8627. [PMID: 32576681 PMCID: PMC7329383 DOI: 10.1126/scisignal.aba8627] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Receptor tyrosine kinases (RTKs) are often overexpressed or mutated in cancers and drive tumor growth and metastasis. In the current model of RTK signaling, including that of MET, downstream phosphatidylinositol 3-kinase (PI3K) mediates both cell proliferation and cell migration, whereas the small guanosine triphosphatase (GTPase) Rac1 mediates cell migration. However, in cultured NIH3T3 and glioblastoma cells, we found that class I PI3K mediated oncogenic MET-induced cell migration but not anchorage-independent growth. In contrast, Rac1 regulated both processes in distinct ways. Downstream of PI3K, Rac1 mediated cell migration through its GTPase activity, whereas independently of PI3K, Rac1 mediated anchorage-independent growth in a GTPase-independent manner through an adaptor function. Through its RKR motif, Rac1 formed a complex with the kinase mTOR to promote its translocation to the plasma membrane, where its activity promoted anchorage-independent growth of the cell cultures. Inhibiting mTOR with rapamycin suppressed the growth of subcutaneous MET-mutant cell grafts in mice, including that of MET inhibitor-resistant cells. These findings reveal a GTPase-independent role for Rac1 in mediating a PI3K-independent MET-to-mTOR pathway and suggest alternative or combined strategies that might overcome resistance to RTK inhibitors in patients with cancer.
Collapse
Affiliation(s)
- Alexia Hervieu
- Spatial Signalling Team, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, Charterhouse Square, London EC1M 6BQ, UK
- Signal Transduction and Molecular Pharmacology Team, CRUK Cancer Therapeutics Unit, Division of Cancer Therapeutics, Institute of Cancer Research, 15 Cotswold Road, Sutton, London SM2 5NG, UK
| | - Sara Farrah Heuss
- Spatial Signalling Team, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, Charterhouse Square, London EC1M 6BQ, UK
| | - Chi Zhang
- Signal Transduction and Molecular Pharmacology Team, CRUK Cancer Therapeutics Unit, Division of Cancer Therapeutics, Institute of Cancer Research, 15 Cotswold Road, Sutton, London SM2 5NG, UK
| | - Rachel Barrow-McGee
- Spatial Signalling Team, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, Charterhouse Square, London EC1M 6BQ, UK
| | - Carine Joffre
- Spatial Signalling Team, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, Charterhouse Square, London EC1M 6BQ, UK
| | - Ludovic Ménard
- Spatial Signalling Team, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, Charterhouse Square, London EC1M 6BQ, UK
| | - Paul Andrew Clarke
- Signal Transduction and Molecular Pharmacology Team, CRUK Cancer Therapeutics Unit, Division of Cancer Therapeutics, Institute of Cancer Research, 15 Cotswold Road, Sutton, London SM2 5NG, UK
| | - Stéphanie Kermorgant
- Spatial Signalling Team, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, Charterhouse Square, London EC1M 6BQ, UK.
| |
Collapse
|
26
|
Xenou L, Papakonstanti E. p110δ PI3K as a therapeutic target of solid tumours. Clin Sci (Lond) 2020; 134:1377-97. [DOI: 10.1042/cs20190772] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 05/21/2020] [Accepted: 06/01/2020] [Indexed: 12/12/2022]
Abstract
AbstractFrom the time of first characterization of PI3K as a heterodimer made up of a p110 catalytic subunit and a regulatory subunit, a wealth of evidence have placed the class IA PI3Ks at the forefront of drug development for the treatment of various diseases including cancer. The p110α isoform was quickly brought at the centre of attention in the field of cancer research by the discovery of cancer-specific gain-of-function mutations in PIK3CA gene in a range of human solid tumours. In contrast, p110δ PI3K was placed into the spotlight of immunity, inflammation and haematologic malignancies because of the preferential expression of this isoform in leucocytes and the rare mutations in PIK3CD gene. The last decade, however, several studies have provided evidence showing that the correlation between the PIK3CA mutations and the response to PI3K inhibition is less clear than originally considered, whereas concurrently an unexpected role of p110δ PI3K in solid tumours has being emerging. While PIK3CD is mostly non-mutated in cancer, the expression levels of p110δ protein seem to act as an intrinsic cancer-causing driver in various solid tumours including breast, prostate, colorectal and liver cancer, Merkel-Cell carcinoma, glioblastoma and neurobalstoma. Furthermore, p110δ selective inhibitors are being studied as potential single agent treatments or as combination partners in attempt to improve cancer immunotherapy, with both strategies to shown great promise for the treatment of several solid tumours. In this review, we discuss the evidence implicating the p110δ PI3K in human solid tumours, their impact on the current state of the field and the potential of using p110δ-selective inhibitors as monotherapy or combined therapy in different cancer contexts.
Collapse
|
27
|
Affiliation(s)
- Alessandra Ghigo
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, Torino, Italy
| |
Collapse
|
28
|
Abstract
Phosphoinositide 3-kinases (PI3Ks) are lipid kinases that regulate important intracellular signalling and vesicle trafficking events via the generation of 3-phosphoinositides. Comprising eight core isoforms across three classes, the PI3K family displays broad expression and function throughout mammalian tissues, and the (patho)physiological roles of these enzymes in the cardiovascular system present the PI3Ks as potential therapeutic targets in settings such as thrombosis, atherosclerosis and heart failure. This review will discuss the PI3K enzymes and their roles in cardiovascular physiology and disease, with a particular focus on platelet function and thrombosis. The current progress and future potential of targeting the PI3K enzymes for therapeutic benefit in cardiovascular disease will be considered, while the challenges of developing drugs against these master cellular regulators will be discussed.
Collapse
Affiliation(s)
- Tom N Durrant
- Department of Chemistry, University of Oxford, Oxford, OX1 3QZ, UK.
| | - Ingeborg Hers
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences Building, University Walk, Bristol, BS8 1TD, UK.
| |
Collapse
|
29
|
Abstract
The phosphoinositide 3 (PI3)-kinase/Akt signaling pathway has always been a focus of interest in breast cancer due to its role in cell growth, cell proliferation, cell migration and deregulated apoptosis. Its activation has been linked to endocrine resistance and worse prognosis in certain subgroups of breast cancer. In addition, deregulation of the PI3K/Akt pathway including PIK3CA activating mutation is frequently present in breast cancer. Multiple efforts have been carried out to target this pathway, initially with pan-PI3K inhibitors with some hint of activity but hampered by their limiting side-effects. A recent large randomized trial in patients with endocrine-resistant PIK3CA-mutant hormone receptor (HR)-positive tumors led to the approval of the first PI3K inhibitor, alpelisib, in combination with fulvestrant. The specificity of alpelisib against the p110α catalytic isoform provided additional efficacy and a better toxicity profile. In this review, we summarize the main research with PI3K inhibitors in breast cancer and we provide some insight of potential future combinations of this treatment in breast cancer patients.
Collapse
Affiliation(s)
- B Verret
- Medical Oncology Department, Gustave Roussy Cancer Campus, Villejuif, France
| | - J Cortes
- IOB Institute of Oncology, Quiron, Madrid & Barcelona
- Department of Medical Oncology, Vall d'Hebron Institute of Oncology (VHIO), Barcelona
- Medica Scientia Innovation Research (MedSIR), Valencia, Spain
- Medica Scientia Innovation Research (MedSIR), New York, USA
| | - T Bachelot
- Medical Oncology Department, Centre Léon Bérard, Lyon
| | - F Andre
- Medical Oncology Department, Gustave Roussy Cancer Campus, Villejuif, France
- Inserm Unit U981, Gustave Roussy Cancer Campus, Villejuif
- Université Paris Sud, Paris-Saclay, France
| | - M Arnedos
- Medical Oncology Department, Gustave Roussy Cancer Campus, Villejuif, France
- Inserm Unit U981, Gustave Roussy Cancer Campus, Villejuif
| |
Collapse
|
30
|
Pirozzi F, Ren K, Murabito A, Ghigo A. PI3K Signaling in Chronic Obstructive Pulmonary Disease: Mechanisms, Targets, and Therapy. Curr Med Chem 2019; 26:2791-2800. [DOI: 10.2174/0929867325666180320120054] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 02/20/2018] [Accepted: 03/06/2018] [Indexed: 12/31/2022]
Abstract
Chronic Obstructive Pulmonary Disease (COPD) is a progressive respiratory disorder characterized by irreversible chronic inflammation and airflow obstruction. It affects more than 64 million patients worldwide and it is predicted to become the third cause of death in the industrialized world by 2030. Currently available therapies are not able to block disease progression and to reduce mortality, underlying the need for a better understanding of COPD pathophysiological mechanisms to identify new molecular therapeutic targets. Recent studies demonstrated that phosphoinositide 3-kinase (PI3K) signaling is prominently activated in COPD and correlates with an increased susceptibility of patients to lung infections. PI3Ks have thus emerged as promising alternative drug targets for COPD and a wide array of pan-isoform and isoform-selective inhibitors have been tested in preclinical models and are currently being evaluated in clinical studies. Here, we summarize the recent knowledge on the involvement of PI3K enzymes in the pathophysiology of COPD, and we discuss the most recent results arising from the preclinical as well as the clinical testing of PI3K inhibitors as novel therapeutics for COPD.
Collapse
Affiliation(s)
- Flora Pirozzi
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Kai Ren
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Alessandra Murabito
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Alessandra Ghigo
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| |
Collapse
|
31
|
Buchanan CM, Lee KL, Shepherd PR. For Better or Worse: The Potential for Dose Limiting the On-Target Toxicity of PI 3-Kinase Inhibitors. Biomolecules 2019; 9:biom9090402. [PMID: 31443495 PMCID: PMC6770514 DOI: 10.3390/biom9090402] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 08/15/2019] [Accepted: 08/21/2019] [Indexed: 02/07/2023] Open
Abstract
The hyper-activation of the phosphoinositide (PI) 3-kinase signaling pathway is a hallmark of many cancers and overgrowth syndromes, and as a result, there has been intense interest in the development of drugs that target the various isoforms of PI 3-kinase. Given the key role PI 3-kinases play in many normal cell functions, there is significant potential for the disruption of essential cellular functions by PI 3-kinase inhibitors in normal tissues; so-called on-target drug toxicity. It is, therefore, no surprise that progress within the clinical development of PI 3-kinase inhibitors as single-agent anti-cancer therapies has been slowed by the difficulty of identifying a therapeutic window. The aim of this review is to place the cellular, tissue and whole-body effects of PI 3-kinase inhibition in the context of understanding the potential for dose limiting on-target toxicities and to introduce possible strategies to overcome these.
Collapse
Affiliation(s)
- Christina M Buchanan
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Kate L Lee
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Peter R Shepherd
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
| |
Collapse
|
32
|
Abstract
Class 1 Phosphoinositide-3-Kinases (PI3Ks) have been widely studied and mediate essential roles in cellular proliferation, chemotaxis, insulin sensitivity, and immunity. Here, we provide a comprehensive overview of how macrophage expressed PI3Ks and their downstream pathways orchestrate responses to metabolic stimuli and nutrients, polarizing macrophages, shaping their cellular identity and function. Particular emphasis will be given to adipose tissue macrophages, crucial players of insulin resistance and chronic metabolically triggered inflammation during obesity. An understanding of PI3K dependent wiring of macrophage responses is important as this is involved in various diseases ranging from obesity, type 2 diabetes to chronic inflammatory disease.
Collapse
Affiliation(s)
- Omar Sharif
- Centre for Physiology and Pharmacology, Institute for Vascular Biology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Julia Stefanie Brunner
- Centre for Physiology and Pharmacology, Institute for Vascular Biology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Andrea Vogel
- Centre for Physiology and Pharmacology, Institute for Vascular Biology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Gernot Schabbauer
- Centre for Physiology and Pharmacology, Institute for Vascular Biology, Medical University Vienna, Vienna, Austria
- Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| |
Collapse
|
33
|
Salloum G, Jakubik CT, Erami Z, Heitz SD, Bresnick AR, Backer JM. PI3Kβ is selectively required for growth factor-stimulated macropinocytosis. J Cell Sci 2019; 132:jcs.231639. [PMID: 31409694 DOI: 10.1242/jcs.231639] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 07/16/2019] [Indexed: 12/16/2022] Open
Abstract
Macropinocytosis is an actin-dependent but clathrin-independent endocytic process by which cells nonselectively take up large aliquots of extracellular material. Macropinocytosis is used for immune surveillance by dendritic cells, as a route of infection by viruses and protozoa, and as a nutrient uptake pathway in tumor cells. In this study, we explore the role of class I phosphoinositide 3-kinases (PI3Ks) during ligand-stimulated macropinocytosis. We find that macropinocytosis in response to receptor tyrosine kinase activation is strikingly dependent on a single class I PI3K isoform, namely PI3Kβ (containing the p110β catalytic subunit encoded by PIK3CB). Loss of PI3Kβ expression or activity blocks macropinocytosis at early steps, before the formation of circular dorsal ruffles, but also plays a role in later steps, downstream from Rac1 activation. PI3Kβ is also required for the elevated levels of constitutive macropinocytosis found in tumor cells that are defective for the PTEN tumor suppressor. Our data shed new light on PI3K signaling during macropinocytosis, and suggest new therapeutic uses for pharmacological inhibitors of PI3Kβ.
Collapse
Affiliation(s)
- Gilbert Salloum
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Charles T Jakubik
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Zahra Erami
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Samantha D Heitz
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Anne R Bresnick
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Jonathan M Backer
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA .,Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| |
Collapse
|
34
|
Erami Z, Heitz S, Bresnick AR, Backer JM. PI3Kβ links integrin activation and PI(3,4)P 2 production during invadopodial maturation. Mol Biol Cell 2019; 30:2367-2376. [PMID: 31318314 PMCID: PMC6741064 DOI: 10.1091/mbc.e19-03-0182] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 06/17/2019] [Accepted: 07/01/2019] [Indexed: 11/17/2022] Open
Abstract
The invasion of tumor cells from the primary tumor is mediated by invadopodia, actin-rich protrusive organelles that secrete matrix metalloproteases and degrade the extracellular matrix. This coupling between protrusive activity and matrix degradation facilitates tumor invasion. We previously reported that the PI3Kβ isoform of PI 3-kinase, which is regulated by both receptor tyrosine kinases and G protein-coupled receptors, is required for invasion and gelatin degradation in breast cancer cells. We have now defined the mechanism by which PI3Kβ regulates invadopodia. We find that PI3Kβ is specifically activated downstream from integrins, and is required for integrin-stimulated spreading and haptotaxis as well as integrin-stimulated invadopodia formation. Surprisingly, these integrin-stimulated and PI3Kβ-dependent responses require the production of PI(3,4)P2 by the phosphoinositide 5'-phosphatase SHIP2. Thus, integrin activation of PI3Kβ is coupled to the SHIP2-dependent production of PI(3,4)P2, which regulates the recruitment of PH domain-containing scaffolds such as lamellipodin to invadopodia. These findings provide novel mechanistic insight into the role of PI3Kβ in the regulation of invadopodia in breast cancer cells.
Collapse
Affiliation(s)
- Zahra Erami
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Samantha Heitz
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Anne R. Bresnick
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Jonathan M. Backer
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461
| |
Collapse
|
35
|
Molinaro A, Becattini B, Mazzoli A, Bleve A, Radici L, Maxvall I, Sopasakis VR, Molinaro A, Bäckhed F, Solinas G. Insulin-Driven PI3K-AKT Signaling in the Hepatocyte Is Mediated by Redundant PI3Kα and PI3Kβ Activities and Is Promoted by RAS. Cell Metab 2019; 29:1400-1409.e5. [PMID: 30982732 DOI: 10.1016/j.cmet.2019.03.010] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 02/04/2019] [Accepted: 03/19/2019] [Indexed: 12/17/2022]
Abstract
Phosphatidylinositol-3-kinase (PI3K) activity is aberrant in tumors, and PI3K inhibitors are investigated as cancer therapeutics. PI3K signaling mediates insulin action in metabolism, but the role of PI3K isoforms in insulin signaling remains unresolved. Defining the role of PI3K isoforms in insulin signaling is necessary for a mechanistic understanding of insulin action and to develop PI3K inhibitors with optimal therapeutic index. We show that insulin-driven PI3K-AKT signaling depends on redundant PI3Kα and PI3Kβ activities, whereas PI3Kδ and PI3Kγ are largely dispensable. We have also found that RAS activity promotes AKT phosphorylation in insulin-stimulated hepatocytes and that promotion of insulin-driven AKT phosphorylation by RAS depends on PI3Kα. These findings reveal the detailed mechanism by which insulin activates AKT, providing an improved mechanistic understanding of insulin signaling. This improved model for insulin signaling predicts that isoform-selective PI3K inhibitors discriminating between PI3Kα and PI3Kβ should be dosed below their hyperglycemic threshold to achieve isoform selectivity.
Collapse
Affiliation(s)
- Angela Molinaro
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Barbara Becattini
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Arianna Mazzoli
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Augusto Bleve
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Lucia Radici
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Ingela Maxvall
- Translational Science, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Victoria Rotter Sopasakis
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Antonio Molinaro
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Fredrik Bäckhed
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden; Novo Nordisk Foundation Center for Basic Metabolic Research, Section for Metabolic Receptology and Enteroendocrinology, Faculty of Health Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Giovanni Solinas
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden.
| |
Collapse
|
36
|
Fujikawa T, Choi YH, Yang DJ, Shin DM, Donato J, Kohno D, Lee CE, Elias CF, Lee S, Kim KW. P110β in the ventromedial hypothalamus regulates glucose and energy metabolism. Exp Mol Med 2019; 51:1-9. [PMID: 31028248 PMCID: PMC6486607 DOI: 10.1038/s12276-019-0249-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 01/10/2019] [Accepted: 01/23/2019] [Indexed: 12/29/2022] Open
Abstract
Phosphoinositide 3-kinase (PI3K) signaling in hypothalamic neurons integrates peripheral metabolic cues, including leptin and insulin, to coordinate systemic glucose and energy homeostasis. PI3K is composed of different subunits, each of which has several unique isoforms. However, the role of the PI3K subunits and isoforms in the ventromedial hypothalamus (VMH), a prominent site for the regulation of glucose and energy homeostasis, is unclear. Here we investigated the role of subunit p110β in steroidogenic factor-1 (SF-1) neurons of the VMH in the regulation of metabolism. Our data demonstrate that the deletion of p110β in SF-1 neurons disrupts glucose metabolism, rendering the mice insulin resistant. In addition, the deletion of p110β in SF-1 neurons leads to the whitening of brown adipose tissues and increased susceptibility to diet-induced obesity due to blunted energy expenditure. These results highlight a critical role for p110β in the regulation of glucose and energy homeostasis via VMH neurons. A particular subunit of a critical signaling enzyme is needed for neurons inside the brain’s hypothalamus to properly regulate energy metabolism. Ki Woo Kim from Yonsei University College of Dentistry, Seoul, South Korea, and colleagues explored the role that the PI3K enzyme plays in neurons of the ventromedial area toward the front of the hypothalamus, a region involved in regulating hunger and metabolism. Deleting a subunit of PI3K called p110β, which is needed for enzymatic function, made mice less responsive to insulin, the hormone that keeps blood sugar levels at healthy levels. As well as having abnormal glucose metabolism, the mice converted more brown fat, which burns energy, into white fat, which stores energy. They were also more susceptible to diet-induced obesity. The findings point toward p110β as a potential drug target for treating diabetes.
Collapse
Affiliation(s)
- Teppei Fujikawa
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Cellular and Integrative Physiology, Long School of Medicine, UT Health San Antonio, San Antonio, TX, USA
| | - Yun-Hee Choi
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Oral Biology, BK21 PLUS, Yonsei University College of Dentistry, Seoul, 03722, Korea
| | - Dong Joo Yang
- Department of Oral Biology, BK21 PLUS, Yonsei University College of Dentistry, Seoul, 03722, Korea
| | - Dong Min Shin
- Department of Oral Biology, BK21 PLUS, Yonsei University College of Dentistry, Seoul, 03722, Korea
| | - Jose Donato
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, 05508000, Brazil
| | - Daisuke Kohno
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, 371-8512, Japan
| | - Charlotte E Lee
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Carol F Elias
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Syann Lee
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA.,Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Ki Woo Kim
- Division of Hypothalamic Research, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, 75390, USA. .,Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, 75390, USA. .,Department of Oral Biology, BK21 PLUS, Yonsei University College of Dentistry, Seoul, 03722, Korea.
| |
Collapse
|
37
|
Abstract
The phosphoinositide 3-kinase (PI3K) family includes eight distinct catalytic subunits and seven regulatory subunits. Only two PI3Ks are directly regulated downstream from G protein-coupled receptors (GPCRs): the class I enzymes PI3Kβ and PI3Kγ. Both enzymes produce phosphatidylinositol 3,4,5-trisposphate in vivo and are regulated by both heterotrimeric G proteins and small GTPases from the Ras or Rho families. However, PI3Kβ is also regulated by direct interactions with receptor tyrosine kinases (RTKs) and their tyrosine phosphorylated substrates, and similar to the class II and III PI3Ks, it binds activated Rab5. The unusually complex regulation of PI3Kβ by small and trimeric G proteins and RTKs leads to a rich landscape of signaling responses at the cellular and organismic levels. This review focuses first on the regulation of PI3Kβ activity in vitro and in cells, and then summarizes the biology of PI3Kβ signaling in distinct tissues and in human disease.
Collapse
Affiliation(s)
- Anne R Bresnick
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York
- Correspondence: Anne R. Bresnick, PhD, or Jonathan M. Backer, MD, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461. E-mail: or
| | - Jonathan M Backer
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York
- Correspondence: Anne R. Bresnick, PhD, or Jonathan M. Backer, MD, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461. E-mail: or
| |
Collapse
|
38
|
Mazloumi Gavgani F, Smith Arnesen V, Jacobsen RG, Krakstad C, Hoivik EA, Lewis AE. Class I Phosphoinositide 3-Kinase PIK3CA/p110α and PIK3CB/p110β Isoforms in Endometrial Cancer. Int J Mol Sci 2018; 19:E3931. [PMID: 30544563 DOI: 10.3390/ijms19123931] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 11/26/2018] [Accepted: 12/03/2018] [Indexed: 12/24/2022] Open
Abstract
The phosphoinositide 3-kinase (PI3K) signalling pathway is highly dysregulated in cancer, leading to elevated PI3K signalling and altered cellular processes that contribute to tumour development. The pathway is normally orchestrated by class I PI3K enzymes and negatively regulated by the phosphatase and tensin homologue, PTEN. Endometrial carcinomas harbour frequent alterations in components of the pathway, including changes in gene copy number and mutations, in particular in the oncogene PIK3CA, the gene encoding the PI3K catalytic subunit p110α, and the tumour suppressor PTEN. PIK3CB, encoding the other ubiquitously expressed class I isoform p110β, is less frequently altered but the few mutations identified to date are oncogenic. This isoform has received more research interest in recent years, particularly since PTEN-deficient tumours were found to be reliant on p110β activity to sustain transformation. In this review, we describe the current understanding of the common and distinct biochemical properties of the p110α and p110β isoforms, summarise their mutations and highlight how they are targeted in clinical trials in endometrial cancer.
Collapse
|
39
|
Goulielmaki E, Bermudez-Brito M, Andreou M, Tzenaki N, Tzardi M, de Bree E, Tsentelierou E, Makrigiannakis A, Papakonstanti EA. Pharmacological inactivation of the PI3K p110δ prevents breast tumour progression by targeting cancer cells and macrophages. Cell Death Dis 2018; 9:678. [PMID: 29880805 PMCID: PMC5992183 DOI: 10.1038/s41419-018-0717-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 04/01/2018] [Accepted: 04/20/2018] [Indexed: 01/12/2023]
Abstract
Patient selection for PI3K-targeted solid cancer treatment was based on the PIK3CA/PTEN mutational status. However, it is increasingly clear that this is not a good predictor of the response of breast cancer cells to the anti-proliferative effect of PI3K inhibitors, indicating that isoform(s) other than p110α may modulate cancer cells sensitivity to PI3K inhibition. Surprisingly, we found that although no mutations in the p110δ subunit have been detected thus far in breast cancer, the expression of p110δ becomes gradually elevated during human breast cancer progression from grade I to grade III. Moreover, pharmacological inactivation of p110δ in mice abrogated the formation of tumours and the recruitment of macrophages to tumour sites and strongly affected the survival, proliferation and apoptosis of grafted tumour cells. Pharmacological inactivation of p110δ in mice with defective macrophages or in mice with normal macrophages but grafted with p110δ-lacking tumours suppressed only partly tumour growth, indicating a requisite role of p110δ in both macrophages and cancer cells in tumour progression. Adoptive transfer of δD910A/D910A macrophages into mice with defected macrophages suppressed tumour growth, eliminated the recruitment of macrophages to tumour sites and prevented metastasis compared with mice that received WT macrophages further establishing that inactivation of p110δ in macrophage prevents tumour progression. Our work provides the first in vivo evidence for a critical role of p110δ in cancer cells and macrophages during solid tumour growth and may pave the way for the use of p110δ inhibitors in breast cancer treatment.
Collapse
Affiliation(s)
- Evangelia Goulielmaki
- Department of Biochemistry, School of Medicine, University of Crete, Heraklion, Greece
| | - Miriam Bermudez-Brito
- Department of Biochemistry, School of Medicine, University of Crete, Heraklion, Greece
| | - Margarita Andreou
- Department of Biochemistry, School of Medicine, University of Crete, Heraklion, Greece
| | - Niki Tzenaki
- Department of Biochemistry, School of Medicine, University of Crete, Heraklion, Greece
| | - Maria Tzardi
- Department of Pathology, University Hospital, School of Medicine, University of Crete, Heraklion, Greece
| | - Eelco de Bree
- Department of Surgical Oncology, University Hospital, School of Medicine, University of Crete, Heraklion, Greece
| | - Eleftheria Tsentelierou
- Department of Obstetrics and Gynaecology, University Hospital, School of Medicine, University of Crete, Heraklion, Greece
| | - Antonis Makrigiannakis
- Department of Obstetrics and Gynaecology, University Hospital, School of Medicine, University of Crete, Heraklion, Greece
| | | |
Collapse
|
40
|
Zhang J, Gao X, Schmit F, Adelmant G, Eck MJ, Marto JA, Zhao JJ, Roberts TM. CRKL Mediates p110β-Dependent PI3K Signaling in PTEN-Deficient Cancer Cells. Cell Rep 2018; 20:549-557. [PMID: 28723560 DOI: 10.1016/j.celrep.2017.06.054] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 05/01/2017] [Accepted: 06/20/2017] [Indexed: 02/03/2023] Open
Abstract
The p110β isoform of PI3K is preferentially activated in many tumors deficient in the phosphatase and tensin homolog (PTEN). However, the mechanism(s) linking PTEN loss to p110β activation remain(s) mysterious. Here, we identify CRKL as a member of the class of PI3Kβ-interacting proteins. Silencing CRKL expression in PTEN-null human cancer cells leads to a decrease in p110β-dependent PI3K signaling and cell proliferation. In contrast, CRKL depletion does not impair p110α-mediated signaling. Further study showed that CRKL binds to tyrosine-phosphorylated p130Cas in PTEN-null cancer cells. Since Src family kinases are known both to be regulated by PTEN and to phosphorylate and activate p130Cas, we tested and found that Src inhibition cooperated with p110β inhibition to suppress the growth of PTEN-null cells. These data suggest both a potential mechanism linking PTEN loss to p110β activation and the possible benefit of dual inhibition of Src and PI3K for PTEN-null tumors.
Collapse
Affiliation(s)
- Jing Zhang
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02215, USA
| | - Xueliang Gao
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02215, USA
| | - Fabienne Schmit
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02215, USA
| | - Guillaume Adelmant
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02215, USA
| | - Michael J Eck
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02215, USA
| | - Jarrod A Marto
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02215, USA
| | - Jean J Zhao
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02215, USA.
| | - Thomas M Roberts
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02215, USA.
| |
Collapse
|
41
|
Dinsmore CJ, Soriano P. MAPK and PI3K signaling: At the crossroads of neural crest development. Dev Biol 2018; 444 Suppl 1:S79-S97. [PMID: 29453943 DOI: 10.1016/j.ydbio.2018.02.003] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 02/06/2018] [Accepted: 02/06/2018] [Indexed: 02/08/2023]
Abstract
Receptor tyrosine kinase-mediated growth factor signaling is essential for proper formation and development of the neural crest. The many ligands and receptors implicated in these processes signal through relatively few downstream pathways, frequently converging on the MAPK and PI3K pathways. Despite decades of study, there is still considerable uncertainty about where and when these signaling pathways are required and how they elicit particular responses. This review summarizes our current understanding of growth factor-induced MAPK and PI3K signaling in the neural crest.
Collapse
Affiliation(s)
- Colin J Dinsmore
- Department of Cell, Developmental and Regenerative Biology, Tisch Cancer Institute, Icahn School of Medicine at Mt. Sinai, New York, NY 10029, USA
| | - Philippe Soriano
- Department of Cell, Developmental and Regenerative Biology, Tisch Cancer Institute, Icahn School of Medicine at Mt. Sinai, New York, NY 10029, USA.
| |
Collapse
|
42
|
Pridham KJ, Varghese RT, Sheng Z. The Role of Class IA Phosphatidylinositol-4,5-Bisphosphate 3-Kinase Catalytic Subunits in Glioblastoma. Front Oncol 2017; 7:312. [PMID: 29326882 PMCID: PMC5736525 DOI: 10.3389/fonc.2017.00312] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 12/04/2017] [Indexed: 12/19/2022] Open
Abstract
Phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) plays a critical role in the pathogenesis of cancer including glioblastoma, the most common and aggressive form of brain cancer. Targeting the PI3K pathway to treat glioblastoma has been tested in the clinic with modest effect. In light of the recent finding that PI3K catalytic subunits (PIK3CA/p110α, PIK3CB/p110β, PIK3CD/p110δ, and PIK3CG/p110γ) are not functionally redundant, it is imperative to determine whether these subunits play divergent roles in glioblastoma and whether selectively targeting PI3K catalytic subunits represents a novel and effective strategy to tackle PI3K signaling. This article summarizes recent advances in understanding the role of PI3K catalytic subunits in glioblastoma and discusses the possibility of selective blockade of one PI3K catalytic subunit as a treatment option for glioblastoma.
Collapse
Affiliation(s)
- Kevin J Pridham
- Virginia Tech Carilion Research Institute, Virginia Tech, Roanoke, VA, United States.,Graduate Program in Translational Biology, Medicine, and Health, Virginia Tech, Blacksburg, VA, United States
| | - Robin T Varghese
- Edward Via College of Osteopathic Medicine, Blacksburg, VA, United States
| | - Zhi Sheng
- Virginia Tech Carilion Research Institute, Virginia Tech, Roanoke, VA, United States.,Virginia Tech Carilion School of Medicine, Virginia Tech, Roanoke, VA, United States.,Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, United States.,Faculty of Health Science, Virginia Tech, Blacksburg, VA, United States
| |
Collapse
|
43
|
|
44
|
Whitecross DE, Anderson DH. Identification of the Binding Sites on Rab5 and p110beta Phosphatidylinositol 3-kinase. Sci Rep 2017; 7:16194. [PMID: 29170408 PMCID: PMC5700975 DOI: 10.1038/s41598-017-16029-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 11/06/2017] [Indexed: 12/19/2022] Open
Abstract
Rab5 is a small monomeric GTPase that mediates protein trafficking during endocytosis. Inactivation of Rab5 by GTP hydrolysis causes a conformational change that masks binding sites on its “switch regions” from downstream effectors. The p85 subunit of phosphatidylinositol 3-kinase (PI3K) is a GTPase activating protein (GAP) towards Rab5. Whereas p85 can bind with both Rab5-GTP and Rab5-GDP, the PI3K catalytic subunit p110β binds only Rab5-GTP, suggesting it interacts with the switch regions. Thus, the GAP functions of the catalytic arginine finger (from p85) and switch region stabilization (from p110β) may be provided by both proteins, acting together. To identify the Rab5 residues involved in binding p110β, residues in the Rab5 switch regions were mutated. A stabilized recombinant p110 protein, where the p85-iSH2 domain was fused to p110 (alpha or beta) was used in binding experiments. Eleven Rab5 mutants, including E80R and H83E, showed reduced p110β binding. The Rab5 binding site on p110β was also resolved through mutation of p110β in its Ras binding domain, and includes residues I234, E238 and Y244. This is a second region within p110β important for Rab5 binding. The Rab5-GTP:p110β interaction may be further elucidated through the characterization of these non-binding mutants in cells.
Collapse
Affiliation(s)
- Dielle E Whitecross
- Cancer Research, Saskatchewan Cancer Agency, 107 Wiggins Road, Saskatoon, Saskatchewan, S7N 5E5, Canada
| | - Deborah H Anderson
- Cancer Research, Saskatchewan Cancer Agency, 107 Wiggins Road, Saskatoon, Saskatchewan, S7N 5E5, Canada. .,Departments of Oncology and Biochemistry, College of Medicine, 107 Wiggins Road, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5E5, Canada.
| |
Collapse
|
45
|
Erami Z, Khalil BD, Salloum G, Yao Y, LoPiccolo J, Shymanets A, Nürnberg B, Bresnick AR, Backer JM. Rac1-stimulated macropinocytosis enhances Gβγ activation of PI3Kβ. Biochem J 2017; 474:3903-14. [PMID: 29046393 DOI: 10.1042/BCJ20170279] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 10/05/2017] [Accepted: 10/10/2017] [Indexed: 12/30/2022]
Abstract
Phosphoinositide 3-kinases (PI 3-kinases) are regulated by a diverse range of upstream activators, including receptor tyrosine kinases (RTKs), G-protein-coupled receptors (GPCRs), and small GTPases from the Ras, Rho and Rab families. For the Class IA PI 3-kinase PI3Kβ, two mechanisms for GPCR-mediated regulation have been described: direct binding of Gβγ subunits to the C2-helical domain linker of p110β, and Dock180/Elmo1-mediated activation of Rac1, which binds to the Ras-Binding Domain of p110β. We now show that the integration of these dual pathways is unexpectedly complex. In breast cancer cells, expression of constitutively activated Rac1 (CA-Rac1) along with either GPCR stimulation or expression of Gβγ led to an additive PI3Kβ-dependent activation of Akt. Whereas CA-Rac1-mediated activation of Akt was blocked in cells expressing a mutated PI3Kβ that cannot bind Gβγ, Gβγ and GPCR-mediated activation of Akt was preserved when Rac1 binding to PI3Kβ was blocked. Surprisingly, PI3Kβ-dependent CA-Rac1 signaling to Akt was still seen in cells expressing a mutant p110β that cannot bind Rac1. Instead of directly binding to PI3Kβ, CA-Rac1 acts by enhancing Gβγ coupling to PI3Kβ, as CA-Rac1-mediated Akt activation was blocked by inhibitors of Gβγ. Cells expressing CA-Rac1 exhibited a robust induction of macropinocytosis, and inhibitors of macropinocytosis blocked the activation of Akt by CA-Rac1 or lysophosphatidic acid. Our data suggest that Rac1 can potentiate the activation of PI3Kβ by GPCRs through an indirect mechanism, by driving the formation of macropinosomes that serve as signaling platforms for Gβγ coupling to PI3Kβ.
Collapse
|
46
|
Abstract
Ischemic preconditioning (IPC) limits myocardial infarct size through the activation of the PI3K-Akt signal cascade; however, little is known about the roles of individual PI3K isoforms in cardioprotection. We aimed, therefore, to elucidate the role of the PI3Kα isoform in cardioprotection Pharmacological PI3Kα inhibition was assessed in isolated-perfused mouse hearts subjected to ischemia/reperfusion injury (IRI), either during the IPC procedure or at reperfusion. PI3Kα inhibition abrogated the IPC-induced protective effect at reperfusion, but not when given only during the IPC protocol. These results were confirmed in an in vivo model. Moreover, pharmacological PI3Kα activation by insulin at reperfusion was sufficient to confer cardioprotection against IRI. In addition, PI3Kα was shown to be expressed and activated in mouse cardiomyocytes, mouse cardiac endothelial cells, as well as in mouse and human heart tissue. Furthermore, PI3Kα was shown to mediate its effect though the inhibition of mitochondrial permeability transition pore opening. In conclusion, PI3Kα activity is required during the early reperfusion phase to reduce myocardial infarct size. This suggests that strategies specifically enhancing the α isoform of PI3K at reperfusion promote tissue salvage and as such, and could provide a direct target for clinical treatment of IRI.
Collapse
Affiliation(s)
- Xavier Rossello
- The Hatter Cardiovascular Institute, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Jaime A Riquelme
- The Hatter Cardiovascular Institute, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Quimicas y Farmaceuticas and Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Zhenhe He
- The Hatter Cardiovascular Institute, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Stasa Taferner
- The Hatter Cardiovascular Institute, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| | | | - Sean M Davidson
- The Hatter Cardiovascular Institute, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Derek M Yellon
- The Hatter Cardiovascular Institute, University College London, 67 Chenies Mews, London, WC1E 6HX, UK.
| |
Collapse
|
47
|
Abstract
Phosphatidylinositide 3 kinases (PI3Ks) and their downstream mediators AKT and mammalian target of rapamycin (mTOR) constitute the core components of the PI3K/AKT/mTOR signalling cascade, regulating cell proliferation, survival and metabolism. Although these functions are well-defined in the context of tumorigenesis, recent studies - in particular those using pluripotent stem cells - have highlighted the importance of this pathway to development and cellular differentiation. Here, we review the recent in vitro and in vivo evidence for the role PI3K/AKT/mTOR signalling plays in the control of pluripotency and differentiation, with a particular focus on the molecular mechanisms underlying these functions.
Collapse
Affiliation(s)
- Jason S L Yu
- Institute of Reproductive and Developmental Biology, Department of Surgery and Cancer, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Wei Cui
- Institute of Reproductive and Developmental Biology, Department of Surgery and Cancer, Imperial College London, Du Cane Road, London W12 0NN, UK
| |
Collapse
|
48
|
Abstract
Receptor signaling relays on intracellular events amplified by secondary and tertiary messenger molecules. In cardiomyocytes and smooth muscle cells, cyclic AMP (cAMP) and subsequent calcium (Ca2+) fluxes are the best characterized receptor-regulated signaling events. However, most of receptors able to modify contractility and other intracellular responses signal through a variety of other messengers, and whether these signaling events are interconnected has long remained unclear. For example, the PI3K (phosphoinositide 3-kinase) pathway connected to the production of the lipid second messenger PIP3/PtdIns(3,4,5)P3 (phosphatidylinositol (3,4,5)-trisphosphate) is potentially involved in metabolic regulation, activation of hypertrophy, and survival pathways. Recent studies, highlighted in this review, started to interconnect PI3K pathway activation to Ca2+ signaling. This interdependency, by balancing contractility with metabolic control, is crucial for cells of the cardiovascular system and is emerging to play key roles in disease development. Better understanding of the interplay between Ca2+ and PI3K signaling is, thus, expected to provide new ground for therapeutic intervention. This review explores the emerging molecular mechanisms linking Ca2+ and PI3K signaling in health and disease.
Collapse
Affiliation(s)
- Alessandra Ghigo
- From the Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino, Italy (A.G., M. Li, E.H.); and INSERM U1048, I2MC and Université Toulouse III, France (M. Laffargue)
| | - Muriel Laffargue
- From the Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino, Italy (A.G., M. Li, E.H.); and INSERM U1048, I2MC and Université Toulouse III, France (M. Laffargue)
| | - Mingchuan Li
- From the Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino, Italy (A.G., M. Li, E.H.); and INSERM U1048, I2MC and Université Toulouse III, France (M. Laffargue)
| | - Emilio Hirsch
- From the Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino, Italy (A.G., M. Li, E.H.); and INSERM U1048, I2MC and Université Toulouse III, France (M. Laffargue).
| |
Collapse
|
49
|
Chaudhari A, Ejeskär K, Wettergren Y, Kahn CR, Rotter Sopasakis V. Hepatic deletion of p110α and p85α results in insulin resistance despite sustained IRS1-associated phosphatidylinositol kinase activity. F1000Res 2017; 6:1600. [PMID: 29983910 PMCID: PMC6020741 DOI: 10.12688/f1000research.12418.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/25/2017] [Indexed: 09/27/2023] Open
Abstract
BACKGROUND Class IA phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) is an integral mediator of insulin signaling. The p110 catalytic and p85 regulatory subunits of PI3K are the products of separate genes, and while they come together to make the active heterodimer, they have opposing roles in insulin signaling and action. Deletion of hepatic p110α results in an impaired insulin signal and severe insulin resistance, whereas deletion of hepatic p85α results in improved insulin sensitivity due to sustained levels of phosphatidylinositol (3,4,5)-trisphosphate. Here, we created mice with combined hepatic deletion of p110α and p85α (L-DKO) to study the impact on insulin signaling and whole body glucose homeostasis. METHODS Six-week old male flox control and L-DKO mice were studied over a period of 18 weeks, during which weight and glucose levels were monitored, and glucose tolerance tests, insulin tolerance test and pyruvate tolerance test were performed. Fasting insulin, insulin signaling mediators, PI3K activity and insulin receptor substrate (IRS)1-associated phosphatidylinositol kinase activity were examined at 10 weeks. Liver, muscle and white adipose tissue weight was recorded at 10 weeks and 25 weeks. RESULTS The L-DKO mice showed a blunted insulin signal downstream of PI3K, developed markedly impaired glucose tolerance, hyperinsulinemia and had decreased liver and adipose tissue weights. Surprisingly, however, these mice displayed normal hepatic glucose production, normal insulin tolerance, and intact IRS1-associated phosphatidylinositol kinase activity without compensatory upregulated signaling of other classes of PI3K. CONCLUSIONS The data demonstrate an unexpectedly overall mild metabolic phenotype of the L-DKO mice, suggesting that lipid kinases other than PI3Ks might partially compensate for the loss of p110α/p85α by signaling through other nodes than Akt/Protein Kinase B.
Collapse
Affiliation(s)
- Aditi Chaudhari
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden
- Department of Clinical Chemistry and Transfusion Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Katarina Ejeskär
- Institute of Health and Education, Translational Medicine, University of Skövde, Skövde, Sweden
| | - Yvonne Wettergren
- Department of Surgery, University of Gothenburg, Sahlgrenska University Hospital/Östra, Gothenburg, Sweden
| | - C. Ronald Kahn
- Joslin Diabetes Center and Harvard Medical School, One Joslin Place, Boston, MA, USA
| | - Victoria Rotter Sopasakis
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden
- Department of Clinical Chemistry and Transfusion Medicine, University of Gothenburg, Gothenburg, Sweden
- Joslin Diabetes Center and Harvard Medical School, One Joslin Place, Boston, MA, USA
| |
Collapse
|
50
|
Chaudhari A, Ejeskär K, Wettergren Y, Kahn CR, Rotter Sopasakis V. Hepatic deletion of p110α and p85α results in insulin resistance despite sustained IRS1-associated phosphatidylinositol kinase activity. F1000Res 2017; 6:1600. [PMID: 29983910 PMCID: PMC6020741 DOI: 10.12688/f1000research.12418.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/01/2018] [Indexed: 12/11/2022] Open
Abstract
Background: Class IA phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) is an integral mediator of insulin signaling. The p110 catalytic and p85 regulatory subunits of PI3K are the products of separate genes, and while they come together to make the active heterodimer, they have opposing roles in insulin signaling and action. Deletion of hepatic p110α results in an impaired insulin signal and severe insulin resistance, whereas deletion of hepatic p85α results in improved insulin sensitivity due to sustained levels of phosphatidylinositol (3,4,5)-trisphosphate. Here, we created mice with combined hepatic deletion of p110α and p85α (L-DKO) to study the impact on insulin signaling and whole body glucose homeostasis. Methods: Six-week old male flox control and L-DKO mice were studied over a period of 18 weeks, during which weight and glucose levels were monitored, and glucose tolerance tests, insulin tolerance test and pyruvate tolerance test were performed. Fasting insulin, insulin signaling mediators, PI3K activity and insulin receptor substrate (IRS)1-associated phosphatidylinositol kinase activity were examined at 10 weeks. Liver, muscle and white adipose tissue weight was recorded at 10 weeks and 25 weeks. Results: The L-DKO mice showed a blunted insulin signal downstream of PI3K, developed markedly impaired glucose tolerance, hyperinsulinemia and had decreased liver and adipose tissue weights. Surprisingly, however, these mice displayed normal hepatic glucose production, normal insulin tolerance, and intact IRS1-associated phosphatidylinositol kinase activity without compensatory upregulated signaling of other classes of PI3K. Conclusions: The data demonstrate an unexpectedly overall mild metabolic phenotype of the L-DKO mice, suggesting that lipid kinases other than PI3Ks might partially compensate for the loss of p110α/p85α by signaling through other nodes than Akt/Protein Kinase B.
Collapse
Affiliation(s)
- Aditi Chaudhari
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden
- Department of Clinical Chemistry and Transfusion Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Katarina Ejeskär
- Institute of Health and Education, Translational Medicine, University of Skövde, Skövde, Sweden
| | - Yvonne Wettergren
- Department of Surgery, University of Gothenburg, Sahlgrenska University Hospital/Östra, Gothenburg, Sweden
| | - C. Ronald Kahn
- Joslin Diabetes Center and Harvard Medical School, One Joslin Place, Boston, MA, USA
| | - Victoria Rotter Sopasakis
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden
- Department of Clinical Chemistry and Transfusion Medicine, University of Gothenburg, Gothenburg, Sweden
- Joslin Diabetes Center and Harvard Medical School, One Joslin Place, Boston, MA, USA
| |
Collapse
|