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Soetkamp D, Gallet R, Parker SJ, Holewinski R, Venkatraman V, Peck K, Goldhaber JI, Marbán E, Van Eyk JE. Myofilament Phosphorylation in Stem Cell Treated Diastolic Heart Failure. Circ Res 2021; 129:1125-1140. [PMID: 34641704 DOI: 10.1161/circresaha.119.316311] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
RATIONALE Phosphorylation of sarcomeric proteins has been implicated in heart failure with preserved ejection fraction (HFpEF); such changes may contribute to diastolic dysfunction by altering contractility, cardiac stiffness, Ca2+-sensitivity, and mechanosensing. Treatment with cardiosphere-derived cells (CDCs) restores normal diastolic function, attenuates fibrosis and inflammation, and improves survival in a rat HFpEF model. OBJECTIVE Phosphorylation changes that underlie HFpEF and those reversed by CDC therapy, with a focus on the sarcomeric subproteome were analyzed. METHODS AND RESULTS Dahl salt-sensitive rats fed a high-salt diet, with echocardiographically verified diastolic dysfunction, were randomly assigned to either intracoronary CDCs or placebo. Dahl salt-sensitive rats receiving low salt diet served as controls. Protein and phosphorylated Ser, Thr, and Tyr residues from left ventricular tissue were quantified by mass spectrometry. HFpEF hearts exhibited extensive hyperphosphorylation with 98% of the 529 significantly changed phospho-sites increased compared with control. Of those, 39% were located within the sarcomeric subproteome, with a large group of proteins located or associated with the Z-disk. CDC treatment partially reverted the hyperphosphorylation, with 85% of the significantly altered 76 residues hypophosphorylated. Bioinformatic upstream analysis of the differentially phosphorylated protein residues revealed PKC as the dominant putative regulatory kinase. PKC isoform analysis indicated increases in PKC α, β, and δ concentration, whereas CDC treatment led to a reversion of PKCβ. Use of PKC isoform specific inhibition and overexpression of various PKC isoforms strongly suggests that PKCβ is the dominant kinase involved in hyperphosphorylation in HFpEF and is altered with CDC treatment. CONCLUSIONS Increased protein phosphorylation at the Z-disk is associated with diastolic dysfunction, with PKC isoforms driving most quantified phosphorylation changes. Because CDCs reverse the key abnormalities in HFpEF and selectively reverse PKCβ upregulation, PKCβ merits being classified as a potential therapeutic target in HFpEF, a disease notoriously refractory to medical intervention.
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Affiliation(s)
- Daniel Soetkamp
- Smidt Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Romain Gallet
- Smidt Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Sarah J Parker
- Smidt Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA
| | | | | | - Kiel Peck
- Smidt Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA
| | | | - Eduardo Marbán
- Smidt Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA
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2
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Fakhr Y, Brindley DN, Hemmings DG. Physiological and pathological functions of sphingolipids in pregnancy. Cell Signal 2021; 85:110041. [PMID: 33991614 DOI: 10.1016/j.cellsig.2021.110041] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 05/10/2021] [Accepted: 05/11/2021] [Indexed: 01/12/2023]
Abstract
Signaling by the bioactive sphingolipid, sphingosine 1-phosphate (S1P), and its precursors are emerging areas in pregnancy research. S1P and ceramide levels increase towards end of gestation, suggesting a physiological role in parturition. However, high levels of circulating S1P and ceramide are correlated with pregnancy disorders such as preeclampsia, gestational diabetes mellitus and intrauterine growth restriction. Expression of placental and decidual enzymes that metabolize S1P and S1P receptors are also dysregulated during pregnancy complications. In this review, we provide an in-depth examination of the signaling mechanism of S1P and ceramide in various reproductive tissues during gestation. These factors determine implantation and early pregnancy success by modulating corpus luteum function from progesterone production to luteolysis through to apoptosis. We also highlight the role of S1P through receptor signaling in inducing decidualization and angiogenesis in the decidua, as well as regulating extravillous trophoblast migration to anchor the placenta into the uterine wall. Recent advances on the role of the S1P:ceramide rheostat in controlling the fate of villous trophoblasts and the role of S1P as a negative regulator of trophoblast syncytialization to a multinucleated placental barrier are discussed. This review also explores the role of S1P in anti-inflammatory and pro-inflammatory signaling, its role as a vasoconstrictor, and the effects of S1P metabolizing enzymes and receptors in pregnancy.
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Affiliation(s)
- Yuliya Fakhr
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB T6G 2S2, Canada; Women and Children's Health Research Institute, University of Alberta, Edmonton, AB T6G 1C9, Canada
| | - David N Brindley
- Women and Children's Health Research Institute, University of Alberta, Edmonton, AB T6G 1C9, Canada; Signal Transduction Research Group, Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2S2, Canada; Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, AB T6G 2S2, Canada
| | - Denise G Hemmings
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB T6G 2S2, Canada; Women and Children's Health Research Institute, University of Alberta, Edmonton, AB T6G 1C9, Canada; Li Ka Shing Institute of Virology, University of Alberta, Edmonton, AB T6G 2E1, Canada; Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, AB T6G 2S2, Canada; Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB T6G 2S2, Canada.
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3
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Administration of a Postbiotic Causes Immunomodulatory Responses in Broiler Gut and Reduces Disease Pathogenesis Following Challenge. Microorganisms 2019; 7:microorganisms7080268. [PMID: 31426502 PMCID: PMC6723925 DOI: 10.3390/microorganisms7080268] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 08/09/2019] [Accepted: 08/16/2019] [Indexed: 01/02/2023] Open
Abstract
With the reemergence of poultry diseases such as necrotic enteritis following the restriction of in-feed antibiotics, the search for antibiotic alternatives has become critically important. Postbiotics are non-viable bacterial products or metabolic byproducts from probiotic microorganisms that have positive effects on the host or microbiota. These are a promising alternative to antibiotics. Here, we describe the mechanism of action of a postbiotic in the context of a Clostridium perfringens (C. perfringens) challenge model. By using performance measurements and a peptide array kinome analysis, we describe the kinotypes and signal transduction changes elicited by the postbiotic with and without C. perfringens challenge. The postbiotic improves lesion scores, C. perfringens counts and mortality compared to challenge groups without the postbiotic, and it improves weight gain in the most severely challenged birds. The postbiotic predominantly affects the innate immune response and appears immunomodulatory. In the context of infection, it reduces the proinflammatory responses and generates a homeostatic-like response. This postbiotic is a viable alternative to antibiotics to improve poultry health in the context of C. perfringens pathogen challenge.
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4
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Dietrich M, Malik MS, Skeie M, Bertelsen V, Stang E. Protein kinase C regulates ErbB3 turnover. Exp Cell Res 2019; 382:111473. [PMID: 31233741 DOI: 10.1016/j.yexcr.2019.06.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 06/14/2019] [Accepted: 06/17/2019] [Indexed: 01/07/2023]
Abstract
ErbB3, which belongs to the epidermal growth factor receptor (EGFR) or ErbB family of receptor tyrosine kinases, is involved in progression of several human cancers and a tight regulation of its expression is crucial. An important mechanism for regulation of ErbB proteins is endocytosis and we recently showed that ErbB3, contrary to other ErbB proteins, like EGFR and ErbB2, is constitutively internalized and degraded. Several studies show that protein kinase C (PKC) can regulate the activation, localization and stability of EGFR and ErbB2. Activation of PKC causes their down-regulation from the plasma membrane, but instead of being degraded the receptors accumulate in an endosomal recycling compartment. Since little is known about possible connections between ErbB3 and PKC, we have in the present study investigated effects PKC activity has on ErbB3 stability and intracellular trafficking. While PKC inhibition tends to increase ErbB3 degradation, activation of PKC causes ErbB3 stabilization. The stabilization was not due to inhibited internalization, on the contrary we find that expression of ErbB3 at the plasma membrane is reduced upon PMA-induced PKC activation. However, while endocytosed ErbB3 under normal conditions and upon PKC inhibition is found in early endosomal antigen 1 (EEA1) positive early endosomes and lysosomal-associated membrane protein 1 (LAMP1) positive late endosomes/lysosomes, indicating that it follows the classic degradative pathway, ErbB3 localizes to EEA1 and LAMP1 negative compartments upon PMA-induced activation of PKC. Altogether this shows that PKC regulates the stability of ErbB3, and knockdown experiments show that PKCδ is essential in this process. A likely explanation is that PKC regulates endosomal sorting of ErbB3 and that activated PKC sorts ErbB3 away from the degradative pathway.
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Affiliation(s)
- Markus Dietrich
- Department of Pathology, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | | | - Marianne Skeie
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | | | - Espen Stang
- Department of Pathology, Oslo University Hospital, Oslo, Norway.
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5
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Visualizing bioactive ceramides. Chem Phys Lipids 2018; 216:142-151. [PMID: 30266560 DOI: 10.1016/j.chemphyslip.2018.09.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 09/19/2018] [Accepted: 09/20/2018] [Indexed: 11/23/2022]
Abstract
In the last 30 years, ceramides have been found to mediate a myriad of biological processes. Ceramides have been recognized as bioactive molecules and their metabolizing enzymes are attractive targets in cancer therapy and other diseases. The molecular mechanism of action of cellular ceramides are still not fully established, with insights into roles through modification of lipid rafts, creation of ceramide platforms, ceramide channels, or through regulation of direct protein effectors such as protein phosphatases and kinases. Recently, the 'Many Ceramides' hypothesis focuses on distinct pools of subcellular ceramides and ceramide species as potential defined bioactive entities. Traditional methods that measure changes in ceramide levels in the whole cell, such as mass spectrometry, fluorescent ceramide analogues, and ceramide antibodies, fail to differentiate specific bioactive species at the subcellular level. However, a few ceramide binding proteins have been reported, and a smaller subgroup within these, have been shown to translocate to ceramide-enriched membranes, revealing these localized pools of bioactive ceramides. In this review we want to discuss and consolidate these works and explore the possibility of defining these binding proteins as new tools are emerging to visualize bioactive ceramides in cells. Our goal is to encourage the scientific community to explore these ceramide partners, to improve techniques to refine the list of these binding partners, making possible the identification of specific domains that recognize and bind ceramides to be used to visualize the 'Many Ceramides' in the cell.
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6
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Hage-Sleiman R, Hamze AB, El-Hed AF, Attieh R, Kozhaya L, Kabbani S, Dbaibo G. Ceramide inhibits PKCθ by regulating its phosphorylation and translocation to lipid rafts in Jurkat cells. Immunol Res 2017; 64:869-86. [PMID: 26798039 DOI: 10.1007/s12026-016-8787-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Protein kinase C theta (PKCθ) is a novel, calcium-independent member of the PKC family of kinases that was identified as a central player in T cell signaling and proliferation. Upon T cell activation by antigen-presenting cells, PKCθ gets phosphorylated and activated prior to its translocation to the immunological synapse where it couples with downstream effectors. PKCθ may be regulated by ceramide, a crucial sphingolipid that is known to promote differentiation, growth arrest, and apoptosis. To further investigate the mechanism, we stimulated human Jurkat T cells with either PMA or anti-CD3/anti-CD28 antibodies following induction of ceramide accumulation by adding exogenous ceramide, bacterial sphingomyelinase, or Fas ligation. Our results suggest that ceramide regulates the PKCθ pathway through preventing its critical threonine 538 (Thr538) phosphorylation and subsequent activation, thereby inhibiting the kinase's translocation to lipid rafts. Moreover, this inhibition is not likely to be a generic effect of ceramide on membrane reorganization. Other lipids, namely dihydroceramide, palmitate, and sphingosine, did not produce similar effects on PKCθ. Addition of the phosphatase inhibitors okadaic acid and calyculin A reversed the inhibition exerted by ceramide, and this suggests involvement of a ceramide-activated protein phosphatase. Such previously undescribed mechanism of regulation of PKCθ raises the possibility that ceramide, or one of its derivatives, and may prove valuable in novel therapeutic approaches for disorders involving autoimmunity or excessive inflammation-where PKCθ plays a critical role.
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Affiliation(s)
- Rouba Hage-Sleiman
- Department of Biology, Faculty of Sciences, Lebanese University, Hadath, Lebanon
| | - Asmaa B Hamze
- Department of Biomedical Science, Faculty of Health Sciences, Global University, Batrakiyye, Beirut, Lebanon
| | - Aimée F El-Hed
- Department of Pediatrics and Adolescent Medicine, Center for Infectious Diseases Research, Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, PO Box 11-0236 Riad El Solh, Beirut, Lebanon
| | - Randa Attieh
- Department of Pediatrics and Adolescent Medicine, Center for Infectious Diseases Research, Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, PO Box 11-0236 Riad El Solh, Beirut, Lebanon
| | - Lina Kozhaya
- Department of Pediatrics and Adolescent Medicine, Center for Infectious Diseases Research, Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, PO Box 11-0236 Riad El Solh, Beirut, Lebanon
| | - Sarah Kabbani
- Department of Pediatrics and Adolescent Medicine, Center for Infectious Diseases Research, Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, PO Box 11-0236 Riad El Solh, Beirut, Lebanon
| | - Ghassan Dbaibo
- Department of Pediatrics and Adolescent Medicine, Center for Infectious Diseases Research, Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, PO Box 11-0236 Riad El Solh, Beirut, Lebanon.
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7
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Spassieva S, Bieberich E. Lysosphingolipids and sphingolipidoses: Psychosine in Krabbe's disease. J Neurosci Res 2017; 94:974-81. [PMID: 27638582 DOI: 10.1002/jnr.23888] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Revised: 07/24/2016] [Accepted: 07/25/2016] [Indexed: 12/14/2022]
Abstract
Until recently, lipids were considered inert building blocks of cellular membranes. This changed three decades ago when lipids were found to regulate cell polarity and vesicle transport, and the "lipid raft" concept took shape. The lipid-driven membrane anisotropy in form of "rafts" that associate with proteins led to the view that organized complexes of lipids and proteins regulate various cell functions. Disturbance of this organization can lead to cellular, tissue, and organ malfunction. Sphingolipidoses, lysosomal storage diseases that are caused by enzyme deficiencies in the sphingolipid degradation pathway, were found to be particularly detrimental to the brain. These enzyme deficiencies result in accumulation of sphingolipid metabolites in lysosomes, although it is not yet clear how this accumulation affects the organization of lipids in cellular membranes. Krabbe's disease (KD), or globoid cell leukodystrophy, was one of the first sphingolipidosis for which the raft concept offered a potential mechanism. KD is caused by mutations in the enzyme β-galactocerebrosidase; however, elevation of its substrate, galactosylceramide, is not observed or considered detrimental. Instead, it was found that a byproduct of galactosylceramide metabolism, the lysosphingolipid psychosine, is accumulated. The "psychosine hypothesis" has been refined by showing that psychosine disrupts lipid rafts and vesicular transport critical for the function of glia and neurons. The role of psychosine in KD is an example of how the disruption of sphingolipid metabolism can lead to elevation of a toxic lysosphingolipid, resulting in disruption of cellular membrane organization and neurotoxicity. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Stefka Spassieva
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, Texas
| | - Erhard Bieberich
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, Geogia.
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8
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Liu M, Clarke CJ, Salama MF, Choi YJ, Obeid LM, Hannun YA. Co-ordinated activation of classical and novel PKC isoforms is required for PMA-induced mTORC1 activation. PLoS One 2017; 12:e0184818. [PMID: 28926616 PMCID: PMC5604983 DOI: 10.1371/journal.pone.0184818] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 08/31/2017] [Indexed: 01/19/2023] Open
Abstract
Protein kinase C (PKC) has been shown to activate the mammalian target of rapamycin complex 1 (mTORC1) signaling pathway, a central hub in the regulation of cell metabolism, growth and proliferation. However, the mechanisms by which PKCs activate mTORC1 are still ambiguous. Our previous study revealed that activation of classical PKCs (cPKC) results in the perinuclear accumulation of cPKC and phospholipase D2 (PLD2) in recycling endosomes in a PLD2-dependent manner. Here, we report that mTORC1 activation by phorbol 12,13-myristate acetate (PMA) requires both classic, cPKC, and novel PKC (nPKC) isoforms, specifically PKCη, acting through distinct pathways. The translocation of mTOR to perinuclear lysosomes was detected after treatment of PKC activators, which was not colocalized with PKCα- or RAB11-positive endosomes and was not inhibited by PLD inhibitors. We found that PKCη inhibition by siRNA or bisindolylmaleimide I effectively decreased mTOR accumulation in lysosomes and its activity. Also, we identified that PKCη plays a role upstream of the v-ATPase/Ragulator/Rag pathway in response to PMA. These data provides a spatial aspect to the regulation of mTORC1 by sustained activation of PKC, requiring co-ordinated activation of two distinct elements, the perinuclear accumulation of cPKC- and PLD-containing endosomes and the nPKC-dependent translation of of mTOR in the perinuclear lysosomes. The close proximity of these two distinct compartments shown in this study suggests the possibility that transcompartment signaling may be a factor in the regulation of mTORC1 activity and also underscores the importance of PKCη as a potential therapeutic target of mTORC-related disorders.
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Affiliation(s)
- Mengling Liu
- Department of Medicine, Stony Brook University, Stony Brook, NY, United States of America
- Stony Brook Cancer Center, Stony Brook University Hospital, Stony Brook, NY, United States of America
| | - Christopher J. Clarke
- Department of Medicine, Stony Brook University, Stony Brook, NY, United States of America
- Stony Brook Cancer Center, Stony Brook University Hospital, Stony Brook, NY, United States of America
| | - Mohamed F. Salama
- Department of Medicine, Stony Brook University, Stony Brook, NY, United States of America
- Department of Biochemistry, Faculty of Veterinary Medicine, Mansoura University, Mansoura, Egypt
| | - Yeon Ja Choi
- Stony Brook Cancer Center, Stony Brook University Hospital, Stony Brook, NY, United States of America
- Department of Pathology, Stony Brook University, Stony Brook, NY, United States of America
| | - Lina M. Obeid
- Department of Medicine, Stony Brook University, Stony Brook, NY, United States of America
- Stony Brook Cancer Center, Stony Brook University Hospital, Stony Brook, NY, United States of America
| | - Yusuf A. Hannun
- Department of Medicine, Stony Brook University, Stony Brook, NY, United States of America
- Stony Brook Cancer Center, Stony Brook University Hospital, Stony Brook, NY, United States of America
- Department of Pathology, Stony Brook University, Stony Brook, NY, United States of America
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9
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Heckman CA, Pandey P, Cayer ML, Biswas T, Zhang Z, Boudreau NS. The tumor promoter-activated protein kinase Cs are a system for regulating filopodia. Cytoskeleton (Hoboken) 2017; 74:297-314. [PMID: 28481056 PMCID: PMC5575509 DOI: 10.1002/cm.21373] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Revised: 04/28/2017] [Accepted: 05/01/2017] [Indexed: 01/02/2023]
Abstract
Different protein kinase C (PKC) isoforms have distinct roles in regulating cell functions. The conventional (α, β, γ) and novel (δ, ɛ, η, θ) classes are targets of phorbol ester tumor promoters, which are surrogates of endogenous second messenger, diacylglycerol. The promoter-stimulated disappearance of filopodia was investigated by use of blocking peptides (BPs) that inhibit PKC maturation and/or docking. Filopodia were partially rescued by a peptide representing PKC ɛ hydrophobic sequence, but also by a myristoylated PKC α/β pseudosubstrate sequence, and an inhibitor of T-cell protein tyrosine phosphatase (TC-PTP). The ability to turn over filopodia was widely distributed among PKC isoforms. PKC α and η hydrophobic sequences enhanced filopodia in cells in the absence of tumor promoter treatment. With transcriptional knockdown of PKC α, the content of PKC ɛ predominated over other isoforms. PKC ɛ could decrease filopodia significantly in promoter-treated cells, and this was attributed to ruffling. The presence of PKC α counteracted the PKC ɛ-mediated enhancement of ruffling. The results showed that there were two mechanisms of filopodia downregulation. One operated in the steady-state and relied on PKC α and η. The other was stimulated by tumor promoters and relied on PKC ɛ. Cycles of protrusion and retraction are characteristic of filopodia and are essential for the cell to orient itself during chemotaxis and haptotaxis. By suppressing filopodia, PKC ɛ can create a long-term "memory" of an environmental signal that may act in nature as a mnemonic device to mark the direction of a repulsive signal.
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Affiliation(s)
- Carol A. Heckman
- Department of Biological SciencesBowling Green State UniversityLife Sciences Building Room 217Bowling GreenOhio43403
| | - Pratima Pandey
- Department of Biological SciencesBowling Green State UniversityLife Sciences Building Room 217Bowling GreenOhio43403
| | - Marilyn L. Cayer
- Center for Microscopy and MicroanalysisBowling Green State UniversityLife Sciences Building Room 217Bowling GreenOhio43403
| | - Tania Biswas
- Department of Biological SciencesBowling Green State UniversityLife Sciences Building Room 217Bowling GreenOhio43403
| | - Zhong‐Yin Zhang
- Department of Medicinal Chemistry and Molecular PharmacologyPurdue UniversityRobert E. Heine Pharmacy Building, Room 202A, 575 Stadium Mall DriveWest LafayetteIndiana47907
| | - Nancy S. Boudreau
- Department of Applied Statistics and Operations ResearchBowling Green State University344 Business Administration BuildingBowling GreenOhio43403
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The Role of Tumor Microenvironment in Chemoresistance: To Survive, Keep Your Enemies Closer. Int J Mol Sci 2017; 18:ijms18071586. [PMID: 28754000 PMCID: PMC5536073 DOI: 10.3390/ijms18071586] [Citation(s) in RCA: 277] [Impact Index Per Article: 39.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 07/16/2017] [Accepted: 07/19/2017] [Indexed: 12/12/2022] Open
Abstract
Chemoresistance is a leading cause of morbidity and mortality in cancer and it continues to be a challenge in cancer treatment. Chemoresistance is influenced by genetic and epigenetic alterations which affect drug uptake, metabolism and export of drugs at the cellular levels. While most research has focused on tumor cell autonomous mechanisms of chemoresistance, the tumor microenvironment has emerged as a key player in the development of chemoresistance and in malignant progression, thereby influencing the development of novel therapies in clinical oncology. It is not surprising that the study of the tumor microenvironment is now considered to be as important as the study of tumor cells. Recent advances in technological and analytical methods, especially ‘omics’ technologies, has made it possible to identify specific targets in tumor cells and within the tumor microenvironment to eradicate cancer. Tumors need constant support from previously ‘unsupportive’ microenvironments. Novel therapeutic strategies that inhibit such microenvironmental support to tumor cells would reduce chemoresistance and tumor relapse. Such strategies can target stromal cells, proteins released by stromal cells and non-cellular components such as the extracellular matrix (ECM) within the tumor microenvironment. Novel in vitro tumor biology models that recapitulate the in vivo tumor microenvironment such as multicellular tumor spheroids, biomimetic scaffolds and tumor organoids are being developed and are increasing our understanding of cancer cell-microenvironment interactions. This review offers an analysis of recent developments on the role of the tumor microenvironment in the development of chemoresistance and the strategies to overcome microenvironment-mediated chemoresistance. We propose a systematic analysis of the relationship between tumor cells and their respective tumor microenvironments and our data show that, to survive, cancer cells interact closely with tumor microenvironment components such as mesenchymal stem cells and the extracellular matrix.
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11
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Kitatani K, Usui T, Sriraman SK, Toyoshima M, Ishibashi M, Shigeta S, Nagase S, Sakamoto M, Ogiso H, Okazaki T, Hannun YA, Torchilin VP, Yaegashi N. Ceramide limits phosphatidylinositol-3-kinase C2β-controlled cell motility in ovarian cancer: potential of ceramide as a metastasis-suppressor lipid. Oncogene 2015; 35:2801-12. [PMID: 26364609 PMCID: PMC4791218 DOI: 10.1038/onc.2015.330] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2014] [Revised: 06/19/2015] [Accepted: 07/17/2015] [Indexed: 12/15/2022]
Abstract
Targeting cell motility, which is required for dissemination and metastasis, has therapeutic potential for ovarian cancer metastasis, and regulatory mechanisms of cell motility need to be uncovered for developing novel therapeutics. Invasive ovarian cancer cells spontaneously formed protrusions, such as lamellipodia, which are required for generating locomotive force in cell motility. Short interfering RNA screening identified class II phosphatidylinositol 3-kinase C2β (PI3KC2β) as the predominant isoform of PI3K involved in lamellipodia formation of ovarian cancer cells. The bioactive sphingolipid ceramide has emerged as an antitumorigenic lipid, and treatment with short-chain C6-ceramide decreased the number of ovarian cancer cells with PI3KC2β-driven lamellipodia. Pharmacological analysis demonstrated that long-chain ceramide regenerated from C6-ceramide through the salvage/recycling pathway, at least in part, mediated the action of C6-ceramide. Mechanistically, ceramide was revealed to interact with the PIK-catalytic domain of PI3KC2β and affect its compartmentalization, thereby suppressing PI3KC2β activation and its driven cell motility. Ceramide treatment also suppressed cell motility promoted by epithelial growth factor, which is a prometastatic factor. To examine the role of ceramide in ovarian cancer metastasis, ceramide liposomes were employed and confirmed to suppress cell motility in vitro. Ceramide liposomes had an inhibitory effect on peritoneal metastasis in a murine xenograft model of human ovarian cancer. Metastasis of PI3KC2β knocked-down cells was insensitive to treatment with ceramide liposomes, suggesting specific involvement of ceramide interaction with PI3KC2β in metastasis suppression. Our study identified ceramide as a bioactive lipid that limits PI3KC2β-governed cell motility, and ceramide is proposed to serve as a metastasis-suppressor lipid in ovarian cancer. These findings could be translated into developing ceramide-based therapy for metastatic diseases.
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Affiliation(s)
- K Kitatani
- Tohoku Medical Megabank Organization, Tohoku University Graduate School of Medicine, Tohoku University, Sendai, Japan.,Department of Obstetrics and Gynecology, Tohoku University Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - T Usui
- Tohoku Medical Megabank Organization, Tohoku University Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - S K Sriraman
- Department of Pharmaceutical Sciences, Center for Pharmaceutical Biotechnology and Nanomedicine, Northeastern University, Boston, MA, USA
| | - M Toyoshima
- Department of Obstetrics and Gynecology, Tohoku University Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - M Ishibashi
- Department of Obstetrics and Gynecology, Tohoku University Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - S Shigeta
- Department of Obstetrics and Gynecology, Tohoku University Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - S Nagase
- Department of Obstetrics and Gynecology, Yamagata University, Yamagata, Japan
| | - M Sakamoto
- Department of Obstetrics and Gynecology, Tohoku University Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - H Ogiso
- Department of Life Science, Medical Research Institute, Kanazawa Medical University, Ishikawa, Japan
| | - T Okazaki
- Department of Life Science, Medical Research Institute, Kanazawa Medical University, Ishikawa, Japan.,Department of Medicine, Division of Hematology/Immunology, Kanazawa Medical University, Ishikawa, Japan
| | - Y A Hannun
- Stony Brook Cancer Center and Department of Medicine, Stony Brook University, Stony Brook, NY, USA
| | - V P Torchilin
- Department of Pharmaceutical Sciences, Center for Pharmaceutical Biotechnology and Nanomedicine, Northeastern University, Boston, MA, USA
| | - N Yaegashi
- Tohoku Medical Megabank Organization, Tohoku University Graduate School of Medicine, Tohoku University, Sendai, Japan.,Department of Obstetrics and Gynecology, Tohoku University Graduate School of Medicine, Tohoku University, Sendai, Japan
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12
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Salama MF, Carroll B, Adada M, Pulkoski-Gross M, Hannun YA, Obeid LM. A novel role of sphingosine kinase-1 in the invasion and angiogenesis of VHL mutant clear cell renal cell carcinoma. FASEB J 2015; 29:2803-13. [PMID: 25805832 DOI: 10.1096/fj.15-270413] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 02/25/2015] [Indexed: 12/12/2022]
Abstract
Sphingosine kinase 1 (SK1), the enzyme responsible for sphingosine 1-phosphate (S1P) production, is overexpressed in many human solid tumors. However, its role in clear cell renal cell carcinoma (ccRCC) has not been described previously. ccRCC cases are usually associated with mutations in von Hippel-Lindau (VHL) and subsequent normoxic stabilization of hypoxia-inducible factor (HIF). We previously showed that HIF-2α up-regulates SK1 expression during hypoxia in glioma cells. Therefore, we hypothesized that the stabilized HIF in ccRCC cells will be associated with increased SK1 expression. Here, we demonstrate that SK1 is overexpressed in 786-0 renal carcinoma cells lacking functional VHL, with concomitant high S1P levels that appear to be HIF-2α mediated. Moreover, examining the TCGA RNA seq database shows that SK1 expression was ∼2.7-fold higher in solid tumor tissue from ccRCC patients, and this was associated with less survival. Knockdown of SK1 in 786-0 ccRCC cells had no effect on cell proliferation. On the other hand, this knockdown resulted in an ∼3.5-fold decrease in invasion, less phosphorylation of focal adhesion kinase (FAK), and an ∼2-fold decrease in angiogenesis. Moreover, S1P treatment of SK1 knockdown cells resulted in phosphorylation of FAK and invasion, and this was mediated by S1P receptor 2. These results suggest that higher SK1 and S1P levels in VHL-defective ccRCC could induce invasion in an autocrine manner and angiogenesis in a paracrine manner. Accordingly, targeting SK1 could reduce both the invasion and angiogenesis of ccRCC and therefore improve the survival rate of patients.
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Affiliation(s)
- Mohamed F Salama
- *Stony Brook Cancer Center and the Department of Medicine, Stony Brook University, Health Sciences Center, Stony Brook, New York, USA; Department of Biochemistry, Faculty of Veterinary Medicine, Mansoura University, Mansoura, Egypt; and Northport Veterans Affairs Medical Center, Northport, New York, USA
| | - Brittany Carroll
- *Stony Brook Cancer Center and the Department of Medicine, Stony Brook University, Health Sciences Center, Stony Brook, New York, USA; Department of Biochemistry, Faculty of Veterinary Medicine, Mansoura University, Mansoura, Egypt; and Northport Veterans Affairs Medical Center, Northport, New York, USA
| | - Mohamad Adada
- *Stony Brook Cancer Center and the Department of Medicine, Stony Brook University, Health Sciences Center, Stony Brook, New York, USA; Department of Biochemistry, Faculty of Veterinary Medicine, Mansoura University, Mansoura, Egypt; and Northport Veterans Affairs Medical Center, Northport, New York, USA
| | - Michael Pulkoski-Gross
- *Stony Brook Cancer Center and the Department of Medicine, Stony Brook University, Health Sciences Center, Stony Brook, New York, USA; Department of Biochemistry, Faculty of Veterinary Medicine, Mansoura University, Mansoura, Egypt; and Northport Veterans Affairs Medical Center, Northport, New York, USA
| | - Yusuf A Hannun
- *Stony Brook Cancer Center and the Department of Medicine, Stony Brook University, Health Sciences Center, Stony Brook, New York, USA; Department of Biochemistry, Faculty of Veterinary Medicine, Mansoura University, Mansoura, Egypt; and Northport Veterans Affairs Medical Center, Northport, New York, USA
| | - Lina M Obeid
- *Stony Brook Cancer Center and the Department of Medicine, Stony Brook University, Health Sciences Center, Stony Brook, New York, USA; Department of Biochemistry, Faculty of Veterinary Medicine, Mansoura University, Mansoura, Egypt; and Northport Veterans Affairs Medical Center, Northport, New York, USA
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Chen SD, Yin JH, Hwang CS, Tang CM, Yang DI. Anti-apoptotic and anti-oxidative mechanisms of minocycline against sphingomyelinase/ceramide neurotoxicity: implication in Alzheimer's disease and cerebral ischemia. Free Radic Res 2012; 46:940-50. [PMID: 22583533 DOI: 10.3109/10715762.2012.674640] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Sphingolipids represent a major class of lipids in which selected family members act as bioactive molecules that control diverse cellular processes, such as proliferation, differentiation, growth, senescence, migration and apoptosis. Emerging evidence reveals that sphingomyelinase/ceramide pathway plays a pivotal role in neurodegenerative diseases that involve mitochondrial dysfunction, oxidative stress and apoptosis. Minocycline, a semi-synthetic second-generation tetracycline derivative in clinical use for infection control, is also considered an effective protective agent in various neurodegenerative diseases in pre-clinical studies. Acting via multiple mechanisms, including anti-inflammatory, anti-oxidative and anti-apoptotic effects, minocycline is a desirable candidate for clinical trials in both acute brain injury as well as chronic neurodegenerative disorders. This review is focused on the anti-apoptotic and anti-oxidative mechanisms of minocycline against neurotoxicity induced by sphingomyelinase/ceramide in relation to neurodegeneration, particularly Alzheimer's disease and cerebral ischemia.
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Affiliation(s)
- Shang-Der Chen
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
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14
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Liu X, Zhang QH, Yi GH. Regulation of metabolism and transport of sphingosine-1-phosphate in mammalian cells. Mol Cell Biochem 2011; 363:21-33. [DOI: 10.1007/s11010-011-1154-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Accepted: 11/11/2011] [Indexed: 02/04/2023]
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15
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El-Shewy HM, Abdel-Samie SA, Al Qalam AM, Lee MH, Kitatani K, Anelli V, Jaffa AA, Obeid LM, Luttrell LM. Phospholipase C and protein kinase C-β 2 mediate insulin-like growth factor II-dependent sphingosine kinase 1 activation. Mol Endocrinol 2011; 25:2144-56. [PMID: 22016563 DOI: 10.1210/me.2011-0101] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
We recently reported that IGF-II binding to the IGF-II/mannose-6-phosphate (M6P) receptor activates the ERK1/2 cascade by triggering sphingosine kinase 1 (SK1)-dependent transactivation of G protein-coupled sphingosine 1-phosphate (S1P) receptors. Here, we investigated the mechanism of IGF-II/M6P receptor-dependent sphingosine kinase 1 (SK1) activation in human embryonic kidney 293 cells. Pretreating cells with protein kinase C (PKC) inhibitor, bisindolylmaleimide-I, abolished IGF-II-stimulated translocation of green fluorescent protein (GFP)-tagged SK1 to the plasma membrane and activation of endogenous SK1, implicating PKC as an upstream regulator of SK1. Using confocal microscopy to examine membrane translocation of GFP-tagged PKCα, β1, β2, δ, and ζ, we found that IGF-II induced rapid, transient, and isoform-specific translocation of GFP-PKCβ2 to the plasma membrane. Immunoblotting of endogenous PKC phosphorylation confirmed PKCβ2 activation in response to IGF-II. Similarly, IGF-II stimulation caused persistent membrane translocation of the kinase-deficient GFP-PKCβ2 (K371R) mutant, which does not dissociate from the membrane after translocation. IGF-II stimulation increased diacylglycerol (DAG) levels, the established activator of classical PKC. Interestingly, the polyunsaturated fraction of DAG was increased, indicating involvement of phosphatidyl inositol/phospholipase C (PLC). Pretreating cells with the PLC inhibitor, U73122, attenuated IGF-II-dependent DAG production and PKCβ2 phosphorylation, blocked membrane translocation of the kinase-deficient GFP-PKCβ2 (K371R) mutant, and reduced sphingosine 1-phosphate production, suggesting that PLC/PKCβ2 are upstream regulators of SK1 in the pathway. Taken together, these data provide evidence that activation of PLC and PKCβ2 by the IGF-II/M6P receptor are required for the activation of SK1.
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Affiliation(s)
- Hesham M El-Shewy
- Departments of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425, USA.
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16
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Shakor ABA, Taniguchi M, Kitatani K, Hashimoto M, Asano S, Hayashi A, Nomura K, Bielawski J, Bielawska A, Watanabe K, Kobayashi T, Igarashi Y, Umehara H, Takeya H, Okazaki T. Sphingomyelin synthase 1-generated sphingomyelin plays an important role in transferrin trafficking and cell proliferation. J Biol Chem 2011; 286:36053-36062. [PMID: 21856749 DOI: 10.1074/jbc.m111.228593] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Transferrin (Tf) endocytosis and recycling are essential for iron uptake and the regulation of cell proliferation. Tf and Tf receptor (TfR) complexes are internalized via clathrin-coated pits composed of a variety of proteins and lipids and pass through early endosomes to recycling endosomes. We investigated the role of sphingomyelin (SM) synthases (SMS1 and SMS2) in clathrin-dependent trafficking of Tf and cell proliferation. We employed SM-deficient lymphoma cells that lacked SMSs and that failed to proliferate in response to Tf. Transfection of SMS1, but not SMS2, enabled these cells to incorporate SM into the plasma membrane, restoring Tf-mediated proliferation. SM-deficient cells showed a significant reduction in clathrin-dependent Tf uptake compared with the parental SM-producing cells. Both SMS1 gene transfection and exogenous short-chain SM treatment increased clathrin-dependent Tf uptake in SM-deficient cells, with the Tf being subsequently sorted to Rab11-positive recycling endosomes. We observed trafficking of the internalized Tf to late/endolysosomal compartments, and this was not dependent on the clathrin pathway in SM-deficient cells. Thus, SMS1-mediated SM synthesis directs Tf-TfR to undergo clathrin-dependent endocytosis and recycling, promoting the proliferation of lymphoma cells.
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Affiliation(s)
- Abo Bakr Abdel Shakor
- Division of Clinical Laboratory Medicine and Hematology/Oncology, Faculty of Medicine, Tottori University, 86 Nishi-Cho, Yonago 683-8503, Japan
| | - Makoto Taniguchi
- Division of Clinical Laboratory Medicine and Hematology/Oncology, Faculty of Medicine, Tottori University, 86 Nishi-Cho, Yonago 683-8503, Japan
| | - Kazuyuki Kitatani
- Division of Clinical Laboratory Medicine and Hematology/Oncology, Faculty of Medicine, Tottori University, 86 Nishi-Cho, Yonago 683-8503, Japan
| | - Mayumi Hashimoto
- Division of Clinical Laboratory Medicine and Hematology/Oncology, Faculty of Medicine, Tottori University, 86 Nishi-Cho, Yonago 683-8503, Japan
| | - Satoshi Asano
- Division of Clinical Laboratory Medicine and Hematology/Oncology, Faculty of Medicine, Tottori University, 86 Nishi-Cho, Yonago 683-8503, Japan
| | - Akira Hayashi
- Division of Clinical Laboratory Medicine and Hematology/Oncology, Faculty of Medicine, Tottori University, 86 Nishi-Cho, Yonago 683-8503, Japan
| | - Kenichi Nomura
- Division of Clinical Laboratory Medicine and Hematology/Oncology, Faculty of Medicine, Tottori University, 86 Nishi-Cho, Yonago 683-8503, Japan
| | - Jacek Bielawski
- Departmant of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Alicja Bielawska
- Departmant of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Ken Watanabe
- Department of Bone and Joint Disease, National Center for Geriatrics and Gerontology, 35 Gengo, Morioka-cho, Obu, Aichi 474-8511, Japan
| | | | - Yasuyuki Igarashi
- Laboratory of Biomembrane and Biofunctional Chemistry, Faculty of Advanced Life Sciences, Hokkaido University, Kita 21-jo, Nishi 11-choume, Kita-ku, Sapporo 001-0021, Japan
| | - Hisanori Umehara
- Department of Hematology and Immunology, Kanazawa Medical University, 1-1 Daigaku Uchinada, Ishikawa 902-0293, Japan
| | - Hiroyuki Takeya
- Division of Pathological Biochemistry, Department of Biomedical Science, Faculty of Medicine, Tottori University, 86 Nishi-Cho, Yonago 683-8503, Japan
| | - Toshiro Okazaki
- Division of Clinical Laboratory Medicine and Hematology/Oncology, Faculty of Medicine, Tottori University, 86 Nishi-Cho, Yonago 683-8503, Japan; Department of Hematology and Immunology, Kanazawa Medical University, 1-1 Daigaku Uchinada, Ishikawa 902-0293, Japan.
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17
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18
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Ruvolo PP, Zhou L, Watt JC, Ruvolo VR, Burks JK, Jiffar T, Kornblau S, Konopleva M, Andreeff M. Targeting PKC-mediated signal transduction pathways using enzastaurin to promote apoptosis in acute myeloid leukemia-derived cell lines and blast cells. J Cell Biochem 2011; 112:1696-707. [PMID: 21360576 PMCID: PMC3394435 DOI: 10.1002/jcb.23090] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Recent studies in acute myeloid leukemia (AML) suggest activation of pro-proliferative signaling cascades including those mediated by protein kinase C (PKC) represent a poor prognostic factor for patients. The classical PKC isoforms α and β generally support survival signaling and have emerged as important targets for anti-cancer therapy. Enzastaurin is a PKC β inhibitor and is in clinical trials for lymphomas, gliomas, and lung cancer. Presently, it is not known if enzastaurin could be effective against AML. In the current study, we found that high dose enzastaurin was found to promote apoptosis in the AML-derived cell lines and in blast cells from AML patients. The mechanism of cell death, however, likely does not involve PKC β as another PKC β inhibitor was not toxic to AML cell lines and did not promote enzastaurin-induced cell killing. While enzastaurin is fairly specific for PKC β, the agent can inhibit other PKC isoforms at higher concentrations. Enzastaurin was effective at inhibiting PKC α phosphorylation and membrane localization in the AML cell lines and suppressed phosphorylation of BCL2. Furthermore, enzastaurin suppressed activation of ERK (which can be activated by PKC α). Analysis of the serine/threonine phosphorylation profile in HL60 cells after enzastaurin treatment revealed that the drug inhibits the phosphorylation of a distinct set of proteins while promoting phosphorylation of another set of proteins. This suggests the drug may regulate multiple signaling pathways. Taken together, these findings suggest that enzastaurin could be effective in the therapy of AML.
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Affiliation(s)
- Peter P. Ruvolo
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
- Division of Signal Transduction and Apoptosis, University of Minnesota Hormel Institute, Austin, Minnesota
| | - Liran Zhou
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Julie C. Watt
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Vivian R. Ruvolo
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
- Division of Signal Transduction and Apoptosis, University of Minnesota Hormel Institute, Austin, Minnesota
| | - Jared K. Burks
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Tilahun Jiffar
- Division of Signal Transduction and Apoptosis, University of Minnesota Hormel Institute, Austin, Minnesota
| | - Steven Kornblau
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Marina Konopleva
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Michael Andreeff
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
- Department of Stem Cell Transplantation, The University of Texas MD Anderson Cancer Center, Houston, Texas
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19
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Ceramide in stem cell differentiation and embryo development: novel functions of a topological cell-signaling lipid and the concept of ceramide compartments. J Lipids 2010; 2011:610306. [PMID: 21490805 PMCID: PMC3066852 DOI: 10.1155/2011/610306] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Accepted: 11/29/2010] [Indexed: 11/27/2022] Open
Abstract
In the last two decades, the view on the function of ceramide as a sole metabolic precursor for other sphingolipids has completely changed. A plethora of studies has shown that ceramide is an important lipid cell-signaling factor regulating apoptosis in a variety of cell types. With the advent of new stem cell technologies and knockout mice for specific steps in ceramide biosynthesis, this view is about to change again. Recent studies suggest that ceramide is a critical cell-signaling factor for stem cell differentiation and cell polarity, two processes at the core of embryo development. This paper discusses studies on ceramide using in vitro differentiated stem cells, embryo cultures, and knockout mice with the goal of linking specific developmental stages to exciting and novel functions of this lipid. Particular attention is devoted to the concept of ceramide as a topological cell-signaling lipid: a lipid that forms distinct structures (membrane domains and vesicles termed “sphingosome”), which confines ceramide-induced cell signaling pathways to localized and even polarized compartments.
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20
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Józefowski S, Czerkies M, Łukasik A, Bielawska A, Bielawski J, Kwiatkowska K, Sobota A. Ceramide and Ceramide 1-Phosphate Are Negative Regulators of TNF-α Production Induced by Lipopolysaccharide. THE JOURNAL OF IMMUNOLOGY 2010; 185:6960-73. [DOI: 10.4049/jimmunol.0902926] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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21
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Tirado OM, MacCarthy CM, Fatima N, Villar J, Mateo-Lozano S, Notario V. Caveolin-1 promotes resistance to chemotherapy-induced apoptosis in Ewing's sarcoma cells by modulating PKCalpha phosphorylation. Int J Cancer 2010; 126:426-36. [PMID: 19609943 DOI: 10.1002/ijc.24754] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Caveolin-1 (CAV1) has been implicated in the regulation of several signaling pathways and in oncogenesis. Previously, we identified CAV1 as a key determinant of the oncogenic phenotype and tumorigenic activity of cells from tumors of the Ewing's Sarcoma Family (ESFT). However, the possible CAV1 involvement in the chemotherapy resistance commonly presented by an ESFT subset has not been established to date. This report shows that CAV1 expression determines the sensitivity of ESFT cells to clinically relevant chemotherapeutic agents. Analyses of endogenous CAV1 levels in several ESFT cells and ectopic CAV1 expression into ESFT cells expressing low endogenous CAV1 showed that the higher the CAV1 levels, the greater their resistance to drug treatment. Moreover, results from antisense- and shRNA-mediated gene expression knockdown and protein re-expression experiments demonstrated that CAV1 increases the resistance of ESFT cells to doxorubicin (Dox)- and cisplatin (Cp)-induced apoptosis by a mechanism involving the activating phosphorylation of PKCalpha. CAV1 knockdown in ESFT cells led to decreased phospho(Thr(638))-PKCalpha levels and a concomitant sensitization to apoptosis, which were reversed by CAV1 re-expression. These results were recapitulated by PKCalpha knockdown and re-expression in ESFT cells in which CAV1 was previously knocked down, thus demonstrating that phospho(Thr(638))-PKCalpha acts downstream of CAV1 to determine the sensitivity of ESFT cells to chemotherapeutic drugs. These data, along with the finding that CAV1 and phospho(Thr(638))-PKCalpha are co-expressed in approximately 45% of ESFT specimens tested, imply that targeting CAV1 and/or PKCalpha may allow the development of new molecular therapeutic strategies to improve the treatment outcome for patients with ESFT.
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Affiliation(s)
- Oscar M Tirado
- Institut d'Investigació Biomédica de Bellvitge, Centre d'Oncología Molecular, L'Hospitalet de Llobregat, Barcelona, Spain
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22
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The inhibition of lipopolysaccharide-induced tumor necrosis factor-α and nitric oxide production by Clostridium perfringens α-toxin and its relation to α-toxin-induced intracellular ceramide generation. Int J Med Microbiol 2009; 299:554-62. [DOI: 10.1016/j.ijmm.2009.04.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2009] [Revised: 03/04/2009] [Accepted: 04/19/2009] [Indexed: 11/18/2022] Open
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23
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Phospholipase D modulation by ceramide in senescence. Mol Cell Biochem 2009; 337:153-8. [DOI: 10.1007/s11010-009-0294-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Accepted: 10/08/2009] [Indexed: 11/27/2022]
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24
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Qiao H, May JM. Macrophage differentiation increases expression of the ascorbate transporter (SVCT2). Free Radic Biol Med 2009; 46:1221-32. [PMID: 19232538 PMCID: PMC3732409 DOI: 10.1016/j.freeradbiomed.2009.02.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 01/24/2009] [Accepted: 02/05/2009] [Indexed: 12/11/2022]
Abstract
To determine whether macrophage differentiation involves increased uptake of vitamin C, or ascorbic acid, we assessed the expression and function of its transporter SVCT2 during phorbol ester-induced differentiation of human-derived THP-1 monocytes. Induction of THP-1 monocyte differentiation by phorbol 12-myristate 13-acetate (PMA) markedly increased SVCT2 mRNA, protein, and function. When ascorbate was present during PMA-induced differentiation, the increase in SVCT2 protein expression was inhibited, but differentiation was enhanced. PMA-induced SVCT2 protein expression was blocked by inhibitors of protein kinase C (PKC), with most of the affect due to the PKCbetaI and betaII isoforms. Activation of MEK/ERK was sustained up to 48 h after PMA treatment, and the inhibitors completely blocked PMA-stimulated SVCT2 protein expression, indicating an exclusive role for the classical MAP kinase pathway. However, inhibitors of NF-kappaB activation, NADPH oxidase inhibitors, and several antioxidants also partially prevented SVCT2 induction, suggesting diverse distal routes for control of SVCT2 transcription. Both known promoters for the SVCT2 were involved in these effects. In conclusion, PMA-induced monocyte-macrophage differentiation is enhanced by ascorbate and associated with increased expression and function of the SVCT2 protein through a pathway involving sustained activation of PKCbetaI/II, MAP kinase, NADPH oxidase, and NF-kappaB.
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Affiliation(s)
- Huan Qiao
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232-6303, USA
| | - James M. May
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232-6303, USA
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25
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Villar J, Quadri HS, Song I, Tomita Y, Tirado OM, Notario V. PCPH/ENTPD5 expression confers to prostate cancer cells resistance against cisplatin-induced apoptosis through protein kinase Calpha-mediated Bcl-2 stabilization. Cancer Res 2009; 69:102-10. [PMID: 19117992 DOI: 10.1158/0008-5472.can-08-2922] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Prostate cancer (PCa) frequently develops antiapoptotic mechanisms and acquires resistance to anticancer drugs. Therefore, identifying PCa drug resistance determinants should facilitate designing more effective chemotherapeutic regimens. Recently, we described that the PCPH protein becomes highly expressed in human prostatic intraepithelial neoplasia and in PCa, and that the functional interaction between PCPH and protein kinase Cdelta (PKCdelta) increases the invasiveness of human PCa. Here, we report that the functional interaction between PCPH and a different PKC isoform, PKCalpha, confers resistance against cisplatin-induced apoptosis to PCa cells. This interaction elicits a mechanism ultimately resulting in the posttranslational stabilization and subsequent elevated expression of Bcl-2. Stable knockdown of either PCPH, mt-PCPH, or PKCalpha in PCa cells decreased Ser70-phosphorylated Bcl-2 and total Bcl-2 protein, thereby increasing their cisplatin sensitivity. Conversely, forced expression of the PCPH protein or, in particular, of the mt-PCPH oncoprotein increased the levels of phosphorylated PKCalpha concurrently with those of Ser70-phosphorylated and total Bcl-2 protein, thus promoting cisplatin resistance. Consistently, Bcl-2 knockdown sensitized PCa cells to cisplatin treatment and, more importantly, reversed the cisplatin resistance of PCa cells expressing the mt-PCPH oncoprotein. Moreover, reexpression of Bcl-2 in PCPH/mt-PCPH knockdown PCa cells reversed the cisplatin sensitization caused by PCPH or mt-PCPH down-regulation. These findings identify PCPH and mt-PCPH as important participants in the chemotherapy response of PCa cells, establish a role for PCPH-PKCalpha-Bcl-2 functional interactions in the drug response process, and imply that targeting PCPH expression before, or simultaneously with, chemotherapy may improve the treatment outcome for PCa patients.
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Affiliation(s)
- Joaquín Villar
- Laboratory of Experimental Carcinogenesis, Department of Radiation Medicine, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, 3970 Reservoir Road Northwest, Washington, DC 20057-1482, USA
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26
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Tazzari PL, Tabellini G, Ricci F, Papa V, Bortul R, Chiarini F, Evangelisti C, Martinelli G, Bontadini A, Cocco L, McCubrey JA, Martelli AM. Synergistic proapoptotic activity of recombinant TRAIL plus the Akt inhibitor Perifosine in acute myelogenous leukemia cells. Cancer Res 2008; 68:9394-403. [PMID: 19010914 DOI: 10.1158/0008-5472.can-08-2815] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
To potentiate the response of acute myelogenous leukemia (AML) cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) cytotoxicity, we have examined the efficacy of a combination with perifosine, a novel phosphatidylinositol-3-kinase (PI3K)/Akt signaling inhibitor. The rationale for using such a combination is that perifosine was recently described to increase TRAIL-R2 receptor expression and decrease the cellular FLICE-inhibitory protein (cFLIP) in human lung cancer cell lines. Perifosine and TRAIL both induced cell death by apoptosis in the THP-1 AML cell line, which is characterized by constitutive PI3K/Akt activation, but lacks functional p53. Perifosine, at concentrations below IC(50), dephosphorylated Akt and increased TRAIL-R2 levels, as shown by Western blot, reverse transcription-PCR, and flow cytometric analysis. Perifosine also decreased the long isoform of cFLIP (cFLIP-L) and the X-linked inhibitor of apoptosis protein (XIAP) expression. Perifosine and TRAIL synergized to activate caspase-8 and induce apoptosis, which was blocked by a caspase-8-selective inhibitor. Up-regulation of TRAIL-R2 expression was dependent on a protein kinase Calpha/c-Jun-NH(2)-kinase 2/c-Jun signaling pathway activated by perifosine through reactive oxygen species production. Perifosine also synergized with TRAIL in primary AML cells displaying constitutive activation of the Akt pathway by inducing apoptosis, Akt dephosphorylation, TRAIL-R2 up-regulation, cFLIP-L and XIAP down-regulation, and c-Jun phosphorylation. The combined treatment negatively affected the clonogenic activity of CD34(+) cells from patients with AML. In contrast, CD34(+) cells from healthy donors were resistant to perifosine and TRAIL treatment. Our findings suggest that the combination of perifosine and TRAIL might offer a novel therapeutic strategy for AML.
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Affiliation(s)
- Pier Luigi Tazzari
- Servizio di Immunoematologia e Trasfusionale, Policlinico S. Orsola-Malpighi, Università di Bologna, Italy
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27
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Abstract
Protein kinase C (PKC) isoforms comprise a family of lipid-activated enzymes that have been implicated in a wide range of cellular functions. PKCs are modular enzymes comprised of a regulatory domain (that contains the membrane-targeting motifs that respond to lipid cofactors, and in the case of some PKCs calcium) and a relatively conserved catalytic domain that binds ATP and substrates. These enzymes are coexpressed and respond to similar stimulatory agonists in many cell types. However, there is growing evidence that individual PKC isoforms subserve unique (and in some cases opposing) functions in cells, at least in part as a result of isoform-specific subcellular compartmentalization patterns, protein-protein interactions, and posttranslational modifications that influence catalytic function. This review focuses on the structural basis for differences in lipid cofactor responsiveness for individual PKC isoforms, the regulatory phosphorylations that control the normal maturation, activation, signaling function, and downregulation of these enzymes, and the intra-/intermolecular interactions that control PKC isoform activation and subcellular targeting in cells. A detailed understanding of the unique molecular features that underlie isoform-specific posttranslational modification patterns, protein-protein interactions, and subcellular targeting (i.e., that impart functional specificity) should provide the basis for the design of novel PKC isoform-specific activator or inhibitor compounds that can achieve therapeutically useful changes in PKC signaling in cells.
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Affiliation(s)
- Susan F Steinberg
- Department of Pharmacology, College of Physicians and Surgeons, Columbia University, New York, New York 10032, USA.
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28
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Ceramide is responsible for the failure of compensatory nerve sprouting in apolipoprotein E knock-out mice. J Neurosci 2008; 28:7891-9. [PMID: 18667621 DOI: 10.1523/jneurosci.1461-08.2008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Apolipoprotein E (apoE) is a key transporter of the cholesterol and phospholipids required for membrane synthesis and nerve growth. We now report a virtual absence in apoE knock-out (KO) mice of normal nerve growth factor (NGF)-driven compensatory sprouting of undamaged cutaneous nociceptive nerves. In contrast, NGF-independent regeneration of crushed axons was unaffected. Essentially similar results came from aged wild-type mice. In apoE KO mice, the endogenous sprouting stimulus was suspect, because NGF administration induced normal sprouting; nevertheless, NGF increased normally in denervated skin, transported normally in the axons, and led to phosphorylation of trkA, erk1, and erk2. However, sprouting was restored in apoE KO mice (although not in aged mice) by fumonisin B1, an inhibitor of ceramide synthesis. A shotgun analysis revealed a wide array of changes in individual ceramide species in DRG neurons of apoE KO mice, and the changes for ceramide species OH_N15:0 made it a candidate inhibitor of sprouting (increased in apoE KO mice and normalized by fumonisin B1). Nevertheless, the unknown effects of individual ceramide species on sprouting, as well as the variability of their changed levels in apoE KO mice and how these were affected by fumonisin B1, support a different conclusion. We suggest that absence of apoE expression alters the balance among ceramide species to one that collectively inhibits compensatory sprouting, whereas fumonisin B1 establishes a new balance that allows sprouting. Nontoxic ceramide modulators might usefully promote sprouting and circuitry repair in neurodegenerative disorders in which ceramide species are perturbed, adding to the benefits of reducing ceramide-induced neuronal apoptosis.
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29
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Abstract
Most of the previous work on the sphingolipid ceramide has been devoted to its function as an apoptosis inducer. Recent studies, however, have shown that in stem cells, ceramide has additional nonapoptotic functions. In this article, ceramide signaling will be reviewed in light of 'systems interface biology': as an interconnection of sphingolipid metabolism, membrane biophysics and cell signaling. The focus will be on the metabolic interconversion of ceramide and sphingomyelin or sphingosine-1-phosphate. Lipid rafts and sphingolipid-induced protein scaffolds will be discussed as a membrane interface for lipid-controlled cell signaling. Ceramide/sphingomyelin and ceramide/sphingosine-1-phosphate-interdependent cell-signaling pathways are significant for the regulation of cell polarity, apoptosis and/or proliferation, and as novel pharmacologic targets in cancer and stem cells.
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Affiliation(s)
- Erhard Bieberich
- Institute of Molecular Medicine & Genetics, School of Medicine, Medical College of Georgia, 1120 15th Street, Room CB-2803, Augusta, GA 30912, USA
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30
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Sakaki K, Wu J, Kaufman RJ. Protein kinase Ctheta is required for autophagy in response to stress in the endoplasmic reticulum. J Biol Chem 2008; 283:15370-80. [PMID: 18356160 PMCID: PMC2397484 DOI: 10.1074/jbc.m710209200] [Citation(s) in RCA: 156] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2007] [Revised: 03/17/2008] [Indexed: 12/25/2022] Open
Abstract
Autophagy is an evolutionally conserved process for the bulk degradation of cytoplasmic proteins and organelles. Recent observations indicate that autophagy is induced in response to cellular insults that result in the accumulation of misfolded proteins in the lumen of the endoplasmic reticulum (ER). However, the signaling mechanisms that activate autophagy under these conditions are not understood. Here, we report that ER stress-induced autophagy requires the activation of protein kinase C (PKC), a member of the novel-type PKC family. Induction of ER stress by treatment with either thapsigargin or tunicamycin activated autophagy in immortalized hepatocytes as monitored by the conversion LC3-I to LC3-II, clustering of LC3 into dot-like cytoplasmic structures, and electron microscopic detection of autophagosomes. Pharmacological inhibition of PKC or small interfering RNA-mediated knockdown of PKC prevented the autophagic response to ER stress. Treatment with ER stressors induced PKC phosphorylation within the activation loop and localization of phospho-PKC to LC3-containing dot structures in the cytoplasm. However, signaling through the known unfolded protein response sensors was not required for PKC activation. PKC activation and stress-induced autophagy were blocked by chelation of intracellular Ca(2+) with BAPTA-AM. PKC was not activated or required for autophagy in response to amino acid starvation. These observations indicate that Ca(2+)-dependent PKC activation is specifically required for autophagy in response to ER stress but not in response to amino acid starvation.
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Affiliation(s)
- Kenjiro Sakaki
- Departments of Biological Chemistry and Internal Medicine and the Howard Hughes Medical Institute, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Jun Wu
- Departments of Biological Chemistry and Internal Medicine and the Howard Hughes Medical Institute, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Randal J. Kaufman
- Departments of Biological Chemistry and Internal Medicine and the Howard Hughes Medical Institute, University of Michigan Medical School, Ann Arbor, Michigan 48109
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31
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Majumder N, Bhattacharjee S, Dey R, Bhattacharyya Majumdar S, Pal NK, Majumdar S. Arabinosylated lipoarabinomannan modulates the impaired cell mediated immune response in Mycobacterium tuberculosis H37Rv infected C57BL/6 mice. Microbes Infect 2007; 10:349-57. [PMID: 18417403 DOI: 10.1016/j.micinf.2007.12.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2007] [Revised: 12/10/2007] [Accepted: 12/19/2007] [Indexed: 11/24/2022]
Abstract
Mycobacterium tuberculosis is a facultative intracellular pathogen that flourishes inside the host macrophages. This organism has the ability to deactivate the cell-mediated immune responses involving the down-regulation of pro-inflammatory cytokines, T cell proliferation, apoptosis of CD4+T cells and impairment of the expression of MHC Class II molecules. We observed that Arabinosylated Lipoarabinomannan (Ara-LAM), a glycolipid present in the cell wall of the avirulent Mycobacterium smegmatis, could effectively restrict the growth of tubercle bacilli, induced the transcription of Th1 cytokines in alveolar macrophages (AMs) and splenocytes, enhanced the frequency of CD4+T cells secreting IFN-gamma and induced the expression of MHC Class II molecules on the splenocyte membrane, compared to that of Mycobacterium tuberculosis H37Rv infected C57BL/6 mice. Collectively our findings strongly suggest that Ara-LAM had the potency to restore the impaired cell mediated immune responses in mice infected with Mycobacterium tuberculosis H37Rv, and hence could be utilized as an effective immuno-prophylactic tool in the control of tuberculosis.
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32
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Kitatani K, Idkowiak-Baldys J, Hannun YA. The sphingolipid salvage pathway in ceramide metabolism and signaling. Cell Signal 2007; 20:1010-8. [PMID: 18191382 DOI: 10.1016/j.cellsig.2007.12.006] [Citation(s) in RCA: 436] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2007] [Revised: 11/18/2007] [Accepted: 12/03/2007] [Indexed: 01/12/2023]
Abstract
Sphingolipids are important components of eukaryotic cells, many of which function as bioactive signaling molecules. Of these, ceramide is a central metabolite and plays key roles in a variety of cellular responses, including regulation of cell growth, viability, differentiation, and senescence. Ceramide is composed of the long-chain sphingoid base, sphingosine, in N-linkage to a variety of acyl groups. Sphingosine serves as the product of sphingolipid catabolism, and it is mostly salvaged through reacylation, resulting in the generation of ceramide or its derivatives. This recycling of sphingosine is termed the "salvage pathway", and recent evidence points to important roles for this pathway in ceramide metabolism and function. A number of enzymes are involved in the salvage pathway, and these include sphingomyelinases, cerebrosidases, ceramidases, and ceramide synthases. Recent studies suggest that the salvage pathway is not only subject to regulation, but it also modulates the formation of ceramide and subsequent ceramide-dependent cellular signals. This review focuses on the salvage pathway in ceramide metabolism, its regulation, its experimental analysis, and emerging biological functions.
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Affiliation(s)
- Kazuyuki Kitatani
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 173 Ashley Avenue, Charleston, South Carolina 29425, United States
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