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Barace S, Santamaría E, Infante S, Arcelus S, De La Fuente J, Goñi E, Tamayo I, Ochoa I, Sogbe M, Sangro B, Hernaez M, Avila MA, Argemi J. Application of Graph Models to the Identification of Transcriptomic Oncometabolic Pathways in Human Hepatocellular Carcinoma. Biomolecules 2024; 14:653. [PMID: 38927057 PMCID: PMC11201933 DOI: 10.3390/biom14060653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 05/22/2024] [Accepted: 05/29/2024] [Indexed: 06/28/2024] Open
Abstract
Whole-tissue transcriptomic analyses have been helpful to characterize molecular subtypes of hepatocellular carcinoma (HCC). Metabolic subtypes of human HCC have been defined, yet whether these different metabolic classes are clinically relevant or derive in actionable cancer vulnerabilities is still an unanswered question. Publicly available gene sets or gene signatures have been used to infer functional changes through gene set enrichment methods. However, metabolism-related gene signatures are poorly co-expressed when applied to a biological context. Here, we apply a simple method to infer highly consistent signatures using graph-based statistics. Using the Cancer Genome Atlas Liver Hepatocellular cohort (LIHC), we describe the main metabolic clusters and their relationship with commonly used molecular classes, and with the presence of TP53 or CTNNB1 driver mutations. We find similar results in our validation cohort, the LIRI-JP cohort. We describe how previously described metabolic subtypes could not have therapeutic relevance due to their overall downregulation when compared to non-tumoral liver, and identify N-glycan, mevalonate and sphingolipid biosynthetic pathways as the hallmark of the oncogenic shift of the use of acetyl-coenzyme A in HCC metabolism. Finally, using DepMap data, we demonstrate metabolic vulnerabilities in HCC cell lines.
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Affiliation(s)
- Sergio Barace
- DNA and RNA Medicine Division, Applied Medical Research Center (CIMA), University of Navarre, 31008 Pamplona, Spain; (S.B.); (E.S.); (S.I.); (S.A.)
| | - Eva Santamaría
- DNA and RNA Medicine Division, Applied Medical Research Center (CIMA), University of Navarre, 31008 Pamplona, Spain; (S.B.); (E.S.); (S.I.); (S.A.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBER-EHD), Av. Monforte de Lemos, 3-5. Pabellón 11, Planta 0, 28029 Madrid, Spain (M.A.A.)
| | - Stefany Infante
- DNA and RNA Medicine Division, Applied Medical Research Center (CIMA), University of Navarre, 31008 Pamplona, Spain; (S.B.); (E.S.); (S.I.); (S.A.)
- Facultad de Medicina Humana, Universidad de Piura, Lima 15074, Peru
| | - Sara Arcelus
- DNA and RNA Medicine Division, Applied Medical Research Center (CIMA), University of Navarre, 31008 Pamplona, Spain; (S.B.); (E.S.); (S.I.); (S.A.)
| | - Jesus De La Fuente
- Bioinformatics Platform, Applied Medical Research Center (CIMA), University of Navarre, 31008 Pamplona, Spain (M.H.)
| | - Enrique Goñi
- Bioinformatics Platform, Applied Medical Research Center (CIMA), University of Navarre, 31008 Pamplona, Spain (M.H.)
| | - Ibon Tamayo
- Bioinformatics Platform, Applied Medical Research Center (CIMA), University of Navarre, 31008 Pamplona, Spain (M.H.)
| | - Idoia Ochoa
- Tecnun School of Engineering (TECNUN), University of Navarre, 31008 Pamplona, Spain;
| | - Miguel Sogbe
- Liver Unit, Tecnun School of Engineering (TECNUN), University of Navarre, 31008 Pamplona, Spain;
| | - Bruno Sangro
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBER-EHD), Av. Monforte de Lemos, 3-5. Pabellón 11, Planta 0, 28029 Madrid, Spain (M.A.A.)
- Liver Unit, Tecnun School of Engineering (TECNUN), University of Navarre, 31008 Pamplona, Spain;
- Instituto de Investigación Sanitaria de Navarra (IdisNA), 31008 Pamplona, Spain
| | - Mikel Hernaez
- Bioinformatics Platform, Applied Medical Research Center (CIMA), University of Navarre, 31008 Pamplona, Spain (M.H.)
- Instituto de Investigación Sanitaria de Navarra (IdisNA), 31008 Pamplona, Spain
| | - Matias A. Avila
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBER-EHD), Av. Monforte de Lemos, 3-5. Pabellón 11, Planta 0, 28029 Madrid, Spain (M.A.A.)
- Instituto de Investigación Sanitaria de Navarra (IdisNA), 31008 Pamplona, Spain
- Solid Tumor Program, Hepatology Laboratory, Applied Medical Research Center (CIMA), University of Navarre, C. de Irunlarrea, 3, 31008 Pamplona, Spain
| | - Josepmaria Argemi
- DNA and RNA Medicine Division, Applied Medical Research Center (CIMA), University of Navarre, 31008 Pamplona, Spain; (S.B.); (E.S.); (S.I.); (S.A.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBER-EHD), Av. Monforte de Lemos, 3-5. Pabellón 11, Planta 0, 28029 Madrid, Spain (M.A.A.)
- Liver Unit, Tecnun School of Engineering (TECNUN), University of Navarre, 31008 Pamplona, Spain;
- Instituto de Investigación Sanitaria de Navarra (IdisNA), 31008 Pamplona, Spain
- Division of Gastroenterology Hepatology and Nutrition, University of Pittsburgh, Pittsburgh, PA 15232, USA
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Jamjoum R, Majumder S, Issleny B, Stiban J. Mysterious sphingolipids: metabolic interrelationships at the center of pathophysiology. Front Physiol 2024; 14:1229108. [PMID: 38235387 PMCID: PMC10791800 DOI: 10.3389/fphys.2023.1229108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 11/27/2023] [Indexed: 01/19/2024] Open
Abstract
Metabolic pathways are complex and intertwined. Deficiencies in one or more enzymes in a given pathway are directly linked with genetic diseases, most of them having devastating manifestations. The metabolic pathways undertaken by sphingolipids are diverse and elaborate with ceramide species serving as the hubs of sphingolipid intermediary metabolism and function. Sphingolipids are bioactive lipids that serve a multitude of cellular functions. Being pleiotropic in function, deficiency or overproduction of certain sphingolipids is associated with many genetic and chronic diseases. In this up-to-date review article, we strive to gather recent scientific evidence about sphingolipid metabolism, its enzymes, and regulation. We shed light on the importance of sphingolipid metabolism in a variety of genetic diseases and in nervous and immune system ailments. This is a comprehensive review of the state of the field of sphingolipid biochemistry.
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Affiliation(s)
- Rama Jamjoum
- Department of Pharmacy, Birzeit University, West Bank, Palestine
| | - Saurav Majumder
- National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health, Rockville, MD, United States
| | - Batoul Issleny
- Department of Pharmacy, Birzeit University, West Bank, Palestine
| | - Johnny Stiban
- Department of Biology and Biochemistry, Birzeit University, West Bank, Palestine
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3
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Qu G, Yang G, Chen D, Tang C, Xu Y. E2F2 serves as an essential prognostic biomarker and therapeutic target for human renal cell carcinoma by presenting "E2F2/miR-16-5p/SPTLC1" schema. Transl Oncol 2023; 34:101699. [PMID: 37300925 DOI: 10.1016/j.tranon.2023.101699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 05/18/2023] [Accepted: 05/22/2023] [Indexed: 06/12/2023] Open
Abstract
BACKGROUND Renal cell carcinoma (RCC) is a common malignant tumor of the urinary system with high mortality and morbidity. Although E2F2, a classical transcription factor implicated in cell cycle, has been shown to foster tumorigenesis in several human cancers, it could not draw a satisfy answer referring to precise downstream signaling axis in RCC development yet. METHODS Based on the publicly available data from TCGA database, expression patterns of E2F2, SPTLC1 and miR-16-5p were identified, either with the ability to predict the prognosis of patients with RCC, which was further validated in 38 paired RCC tissues and matched adjacent tissues by RT-qPCR and Western blot, respectively. Their cellular biofunctions were evaluated using MTT, EdU, Colony formation and transwell assays. Chromatin immunoprecipitation (ChIP) and luciferase reporter assay were employed to certain the exquisite core transcription regulatory circuitry of E2F2/miR-16-5p/SPTLC1 in RCC progression, which was also determined in xenograft tumor model. RESULTS Consistent with the public TCGA database, E2F2 was significantly increased in RCC tissues and cells, indicating shorter overall survival. Mechanistically, E2F2 served as a transcriptional activator of miR-16-5p, thus accounting for its negative regulation on SPTLC1 expression. E2F2 knockdown-mediated suppressive biofunctions on RCC cells were rescued by miR-16-5p mimics, while this effect was abolished again by SPTLC1 overexpression. Role of E2F2 on RCC tumorigenesis via the miR-16-5p/SPTLC1 axis was verified both in vitro and in vivo. CONCLUSION E2F2 promoted RCC progression via the miR-16-5p/SPTLC1 axis, which may represent a novel prognostic and therapeutic biomarker for RCC.
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Affiliation(s)
- GenYi Qu
- Department of Urology, ZhuZhou central hospital, ZhuZhou, Hunan Province 412000, China
| | - Guang Yang
- Department of Urology, ZhuZhou central hospital, ZhuZhou, Hunan Province 412000, China
| | - Dan Chen
- Department of Urology, ZhuZhou central hospital, ZhuZhou, Hunan Province 412000, China
| | - Cheng Tang
- Department of Urology, ZhuZhou central hospital, ZhuZhou, Hunan Province 412000, China
| | - Yong Xu
- Department of Urology, ZhuZhou central hospital, ZhuZhou, Hunan Province 412000, China.
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Li Y, Cao H, Dong T, Wang X, Ma L, Li K, Lou H, Song CP, Ren D. Phosphorylation of the LCB1 subunit of Arabidopsis serine palmitoyltransferase stimulates its activity and modulates sphingolipid biosynthesis. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2023. [PMID: 36738228 DOI: 10.1111/jipb.13461] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Indexed: 06/18/2023]
Abstract
Sphingolipids are the structural components of membrane lipid bilayers and act as signaling molecules in many cellular processes. Serine palmitoyltransferase (SPT) is the first committed and rate-limiting enzyme in the de novo sphingolipids biosynthetic pathway. The core SPT enzyme is a heterodimer consisting of LONG-CHAIN BASE1 (LCB1) and LCB2 subunits. SPT activity is inhibited by orosomucoid proteins and stimulated by small subunits of SPT (ssSPTs). However, whether LCB1 is modified and how such modification might regulate SPT activity have to date been unclear. Here, we show that activation of MITOGEN-ACTIVATED PROTEIN KINASE 3 (MPK3) and MPK6 by upstream MKK9 and treatment with Flg22 (a pathogen-associated molecular pattern) increases SPT activity and induces the accumulation of sphingosine long-chain base t18:0 in Arabidopsis thaliana, with activated MPK3 and MPK6 phosphorylating AtLCB1. Phosphorylation of AtLCB1 strengthened its binding with AtLCB2b, promoted its binding with ssSPTs, and stimulated the formation of higher order oligomeric and active SPT complexes. Our findings therefore suggest a novel regulatory mechanism for SPT activity.
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Affiliation(s)
- Yuan Li
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Hanwei Cao
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Tingting Dong
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Xiaoke Wang
- State Key Laboratory of Agro-Biotechnology and Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Liang Ma
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Kun Li
- Collaborative Innovation Center of Crop Stress Biology, Henan Province. Institute of Plant Stress Biology, School of Life Science, Henan University, Kaifeng, 475001, China
| | - Huiqiang Lou
- State Key Laboratory of Agro-Biotechnology and Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Chun-Peng Song
- Collaborative Innovation Center of Crop Stress Biology, Henan Province. Institute of Plant Stress Biology, School of Life Science, Henan University, Kaifeng, 475001, China
| | - Dongtao Ren
- State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
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Raza Y, Atallah J, Luberto C. Advancements on the Multifaceted Roles of Sphingolipids in Hematological Malignancies. Int J Mol Sci 2022; 23:12745. [PMID: 36361536 PMCID: PMC9654982 DOI: 10.3390/ijms232112745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 10/07/2022] [Accepted: 10/17/2022] [Indexed: 09/19/2023] Open
Abstract
Dysregulation of sphingolipid metabolism plays a complex role in hematological malignancies, beginning with the first historical link between sphingolipids and apoptosis discovered in HL-60 leukemic cells. Numerous manuscripts have reviewed the field including the early discoveries that jumpstarted the studies. Many studies discussed here support a role for sphingolipids, such as ceramide, in combinatorial therapeutic regimens to enhance anti-leukemic effects and reduce resistance to standard therapies. Additionally, inhibitors of specific nodes of the sphingolipid pathway, such as sphingosine kinase inhibitors, significantly reduce leukemic cell survival in various types of leukemias. Acid ceramidase inhibitors have also shown promising results in acute myeloid leukemia. As the field moves rapidly, here we aim to expand the body of literature discussed in previously published reviews by focusing on advances reported in the latter part of the last decade.
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Affiliation(s)
- Yasharah Raza
- Department of Pharmacological Sciences, Molecular and Cellular Pharmacology, Stony Brook University, Stony Brook, NY 11794, USA
- Stony Brook Cancer Center, Stony Brook University Hospital, Stony Brook, NY 11794, USA
| | - Jane Atallah
- Stony Brook Cancer Center, Stony Brook University Hospital, Stony Brook, NY 11794, USA
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY 11794, USA
| | - Chiara Luberto
- Stony Brook Cancer Center, Stony Brook University Hospital, Stony Brook, NY 11794, USA
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY 11794, USA
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Structural insights into the regulation of human serine palmitoyltransferase complexes. Nat Struct Mol Biol 2021; 28:240-248. [PMID: 33558761 PMCID: PMC9812531 DOI: 10.1038/s41594-020-00551-9] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 12/16/2020] [Indexed: 01/31/2023]
Abstract
Sphingolipids are essential lipids in eukaryotic membranes. In humans, the first and rate-limiting step of sphingolipid synthesis is catalyzed by the serine palmitoyltransferase holocomplex, which consists of catalytic components (SPTLC1 and SPTLC2) and regulatory components (ssSPTa and ORMDL3). However, the assembly, substrate processing and regulation of the complex are unclear. Here, we present 8 cryo-electron microscopy structures of the human serine palmitoyltransferase holocomplex in various functional states at resolutions of 2.6-3.4 Å. The structures reveal not only how catalytic components recognize the substrate, but also how regulatory components modulate the substrate-binding tunnel to control enzyme activity: ssSPTa engages SPTLC2 and shapes the tunnel to determine substrate specificity. ORMDL3 blocks the tunnel and competes with substrate binding through its amino terminus. These findings provide mechanistic insights into sphingolipid biogenesis governed by the serine palmitoyltransferase complex.
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7
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Azadi M, Alemi F, Sadeghi S, Mohammadi M, Rahimi NA, Mirzaie S, Vahabi F, Parvaz S, Arjmand M, Zamani Z. An Integrative In Silico Mathematical Modelling Study of The Anti-Cancer Effect of Clove Extract ( Syzygium aromaticum ) Combined with In Vitro Metabolomics Study Using 1HNMR Spectroscopy. IRANIAN JOURNAL OF BIOTECHNOLOGY 2020; 18:e2336. [PMID: 33850939 PMCID: PMC8035415 DOI: 10.30498/ijb.2020.141102.2336] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Clove oil is known for its medicinal properties. The mechanism of anti-cancer properties of Syzygium aromaticum were investigated by mathematical modelling on the genome scale with metabolomics using 1H Nuclear Magnetic Resonance spectroscopy on Raji cells. OBJECTIVES An integrative analysis correlated the metabolites identified by 1HNMR and genes with the detected pathways. MATERIALS AND METHODS Raji cells treated with clove oil were collected and sent for 1HNMR spectroscopy and the spectra analyzed by MATLAB and Human Metabolome Database for metabolite identification. Pathway and topology analysis was implemented using the genes and metabolites in the integrative analysis of Metaboanalyst software. RESULTS 50% inhibitory concentration of clove oil was 50 µg/ml and the model anticipated 74 genes with differentiating metabolites being some amino acids, cholesterol and fucose. CONCLUSION The integrative study predicted that the anti cancer mechanism of clove oil involves novel enzymes, as likely drug targets, 24-dehydrocholesterol reductase and 7-dehydrocholesterol reductase in cholesterol biosynthesis, dehydrofolate reductase in one carbon metabolism and serine palmitoyl-transferase long chain in sphingolipid biosynthesis.
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Affiliation(s)
- Mehri Azadi
- Biochemistry Department, Pasteur Institute of Iran, Tehran, Iran
| | - Fatemeh Alemi
- Chemical Engineering Department, Islamic Azad University, Tehran, Iran
| | - Sedigheh Sadeghi
- Biochemistry Department, Pasteur Institute of Iran, Tehran, Iran
| | - Maryam Mohammadi
- Biochemistry Department, Pasteur Institute of Iran, Tehran, Iran
| | | | - Sako Mirzaie
- Biology Department, Islamic Azad University, Pasdaran Avenue, Sanandaj, Iran
| | - Farideh Vahabi
- Biochemistry Department, Pasteur Institute of Iran, Tehran, Iran
| | - Shirin Parvaz
- Biochemistry Department, Pasteur Institute of Iran, Tehran, Iran
| | - Mohammad Arjmand
- Biochemistry Department, Pasteur Institute of Iran, Tehran, Iran
| | - Zahra Zamani
- Biochemistry Department, Pasteur Institute of Iran, Tehran, Iran
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Kong Z, Guo X, Zhao Z, Wu W, Luo L, Zhu Z, Yin S, Cai C, Wu W, Wang D, Liu Y, Duan X. SPTLC1 inhibits cell growth via modulating Akt/FOXO1 pathway in renal cell carcinoma cells. Biochem Biophys Res Commun 2019; 520:1-7. [PMID: 31554600 DOI: 10.1016/j.bbrc.2019.09.073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 09/18/2019] [Accepted: 09/18/2019] [Indexed: 11/19/2022]
Abstract
Serine palmitoyltransferase long chain-1 (SPTLC1), which is the rate-limiting enzyme for sphingolipid biosynthesis, has been indicated to be essential for carcinoma cell survival and proliferation in recent, but its role in the regulation of renal cell carcinoma (RCC) remains unknown. In the present study, we found that SPTLC1 expression was significantly decreased in RCC tissues compared to non-tumor tissues, and low SPTLC1 expression was associated with poor overall survival of RCC patients. In addition, our results revealed that forced expression of SPTLC1 could significantly inhibit cell growth in vitro and in vivo via, at least in part, modulating Akt/FOXO1 signaling pathway, thus representing a novel role of SPTLC1 in the regulation of tumor growth in RCC for the first time.
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Affiliation(s)
- Zhenzhen Kong
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangdong Key Laboratory of Urology, Guangzhou Institute of Urology, Guangzhou, China
| | - Xinming Guo
- Department of Pharmacy, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, China
| | - Zhijian Zhao
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangdong Key Laboratory of Urology, Guangzhou Institute of Urology, Guangzhou, China
| | - Weizhou Wu
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangdong Key Laboratory of Urology, Guangzhou Institute of Urology, Guangzhou, China
| | - Lianmin Luo
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangdong Key Laboratory of Urology, Guangzhou Institute of Urology, Guangzhou, China
| | - Zhiguo Zhu
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangdong Key Laboratory of Urology, Guangzhou Institute of Urology, Guangzhou, China
| | - Shanfeng Yin
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangdong Key Laboratory of Urology, Guangzhou Institute of Urology, Guangzhou, China
| | - Chao Cai
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangdong Key Laboratory of Urology, Guangzhou Institute of Urology, Guangzhou, China
| | - Wenqi Wu
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangdong Key Laboratory of Urology, Guangzhou Institute of Urology, Guangzhou, China
| | - Ding Wang
- The Third Affiliated Hospital of Guangzhou Medical University, Key Laboratory for Major Obstetric Diseases of Guangdong Province, Guangzhou, China
| | - Yongda Liu
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangdong Key Laboratory of Urology, Guangzhou Institute of Urology, Guangzhou, China.
| | - Xiaolu Duan
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangdong Key Laboratory of Urology, Guangzhou Institute of Urology, Guangzhou, China.
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Abstract
Mechanistic details for the roles of sphingolipids and their downstream targets in the regulation of tumor growth, response to chemo/radiotherapy, and metastasis have been investigated in recent studies using innovative molecular, genetic and pharmacologic tools in various cancer models. Induction of ceramide generation in response to cellular stress by chemotherapy, radiation, or exogenous ceramide analog drugs mediates cell death via apoptosis, necroptosis, or mitophagy. In this chapter, distinct functions and mechanisms of action of endogenous ceramides with different fatty acyl chain lengths in the regulation of cancer cell death versus survival will be discussed. In addition, importance of ceramide subcellular localization, trafficking, and lipid-protein binding between ceramide and various target proteins in cancer cells will be reviewed. Moreover, clinical trials from structure-function-based studies to restore antiproliferative ceramide signaling by activating ceramide synthesis will also be analyzed. Future studies are important to understand the mechanistic involvement of ceramide-mediated cell death in anticancer therapy, including immunotherapy.
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Affiliation(s)
- Rose Nganga
- Department of Biochemistry and Molecular Biology, and Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, United States
| | - Natalia Oleinik
- Department of Biochemistry and Molecular Biology, and Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, United States
| | - Besim Ogretmen
- Department of Biochemistry and Molecular Biology, and Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, United States
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10
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Zhu WK, Xu WH, Wang J, Huang YQ, Abudurexiti M, Qu YY, Zhu YP, Zhang HL, Ye DW. Decreased SPTLC1 expression predicts worse outcomes in ccRCC patients. J Cell Biochem 2019; 121:1552-1562. [PMID: 31512789 DOI: 10.1002/jcb.29390] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 08/28/2019] [Indexed: 12/22/2022]
Abstract
OBJECTIVE Serine palmitoyltransferase, long chain base subunit 1 (SPTLC1) catalyzes the first step in sphingolipid synthesis and has been implicated in the progression of various cancers. However, its role in clear cell renal cell carcinoma (ccRCC) remains unclear. Here, we investigated the expression and prognostic value of SPTLC1 in ccRCC. METHODS Three ccRCC patient cohorts were studied. ccRCC and adjacent normal kidney tissue samples were obtained from 183 patients at the Fudan University Shanghai Cancer Center (FUSCC) and subjected to immunohistochemical staining and quantitative reverse-transcription polymerase chain reaction to evaluate SPTLC1 protein and messenger RNA (mRNA) expression. Two validation cohorts consisting of mRNA and clinicopathological data sets from patients with ccRCC were obtained from the Cancer Genome Atlas (TCGA, n = 429) and Oncomine (n = 178) databases. Associations between low and high SPTLC1 mRNA and protein expression and survival were evaluated using the Kaplan-Meier method and log-rank test. Independent prognostic factors were identified using univariate and multivariate Cox regression analysis. RESULTS SPTLC1 mRNA or protein were expressed at significantly lower levels in ccRCC tissues compared with normal kidney tissues in all three patient cohorts (P < .001). Low SPTLC1 expression was significantly associated with shorter overall survival in the FUSCC (P = .041) and Oncomine (P < .001) cohorts, and was significantly associated with shorter overall survival (P < .0001) and progression-free survival (P < .001) in the TCGA cohort. Bioinformatics analysis identified 10 genes significantly coregulated with SPTLC1 in ccRCC, most of which contributed to sphingomyelin metabolism (SPTLC2, SPTLC3, SPTSSA, SPTSSB, ORMDL1, ORMDL2, ORMDL3, ZDHHC9, GOLGA7B, and KDSR). Functional enrichment analysis predicted that SPTLC1 and its network play significant roles in inflammatory, hypoxia, and interferon gamma responses, and in allograft rejection pathways. CONCLUSION Low SPTLC1 expression is significantly associated with disease progression and poor survival in patients with ccRCC, suggesting that SPTLC1 may function as a tumor suppressor. Thus, SPTLC1 could be a potential new biomarker and/or therapeutic target for ccRCC.
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Affiliation(s)
- Wen-Kai Zhu
- Institutes of Biomedical Science, Fudan University, Shanghai, China.,Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wen-Hao Xu
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jun Wang
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yong-Qiang Huang
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Mierxiati Abudurexiti
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yuan-Yuan Qu
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yi-Ping Zhu
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Hai-Liang Zhang
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Ding-Wei Ye
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
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11
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Dehghani R, Rahmani F, Rezaei N. MicroRNA in Alzheimer's disease revisited: implications for major neuropathological mechanisms. Rev Neurosci 2018; 29:161-182. [PMID: 28941357 DOI: 10.1515/revneuro-2017-0042] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 07/09/2017] [Indexed: 12/28/2022]
Abstract
Pathology of Alzheimer's disease (AD) goes far beyond neurotoxicity resulting from extracellular deposition of amyloid β (Aβ) plaques. Aberrant cleavage of amyloid precursor protein and accumulation of Aβ in the form of the plaque or neurofibrillary tangles are the known primary culprits of AD pathogenesis and target for various regulatory mechanisms. Hyper-phosphorylation of tau, a major component of neurofibrillary tangles, precipitates its aggregation and prevents its clearance. Lipid particles, apolipoproteins and lipoprotein receptors can act in favor or against Aβ and tau accumulation by altering neural membrane characteristics or dynamics of transport across the blood-brain barrier. Lipids also alter the oxidative/anti-oxidative milieu of the central nervous system (CNS). Irregular cell cycle regulation, mitochondrial stress and apoptosis, which follow both, are also implicated in AD-related neuronal loss. Dysfunction in synaptic transmission and loss of neural plasticity contribute to AD. Neuroinflammation is a final trail for many of the pathologic mechanisms while playing an active role in initiation of AD pathology. Alterations in the expression of microRNAs (miRNAs) in AD and their relevance to AD pathology have long been a focus of interest. Herein we focused on the precise pathomechanisms of AD in which miRNAs were implicated. We performed literature search through PubMed and Scopus using the search term: ('Alzheimer Disease') OR ('Alzheimer's Disease') AND ('microRNAs' OR 'miRNA' OR 'MiR') to reach for relevant articles. We show how a limited number of common dysregulated pathways and abnormal mechanisms are affected by various types of miRNAs in AD brain.
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Affiliation(s)
- Reihaneh Dehghani
- Molecular Immunology Research Center, School of Medicine, Tehran University of Medical Sciences, Tehran 1419783151, Iran
| | - Farzaneh Rahmani
- Students Scientific Research Center (SSRC), Tehran University of Medical Sciences, Tehran, Iran
| | - Nima Rezaei
- Molecular Immunology Research Center, School of Medicine, Tehran University of Medical Sciences, Tehran 1419783151, Iran
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12
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Harrison PJ, Dunn T, Campopiano DJ. Sphingolipid biosynthesis in man and microbes. Nat Prod Rep 2018; 35:921-954. [PMID: 29863195 PMCID: PMC6148460 DOI: 10.1039/c8np00019k] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Indexed: 12/20/2022]
Abstract
A new review covering up to 2018 Sphingolipids are essential molecules that, despite their long history, are still stimulating interest today. The reasons for this are that, as well as playing structural roles within cell membranes, they have also been shown to perform a myriad of cell signalling functions vital to the correct function of eukaryotic and prokaryotic organisms. Indeed, sphingolipid disregulation that alters the tightly-controlled balance of these key lipids has been closely linked to a number of diseases such as diabetes, asthma and various neuropathologies. Sphingolipid biogenesis, metabolism and regulation is mediated by a large number of enzymes, proteins and second messengers. There appears to be a core pathway common to all sphingolipid-producing organisms but recent studies have begun to dissect out important, species-specific differences. Many of these have only recently been discovered and in most cases the molecular and biochemical details are only beginning to emerge. Where there is a direct link from classic biochemistry to clinical symptoms, a number a drug companies have undertaken a medicinal chemistry campaign to try to deliver a therapeutic intervention to alleviate a number of diseases. Where appropriate, we highlight targets where natural products have been exploited as useful tools. Taking all these aspects into account this review covers the structural, mechanistic and regulatory features of sphingolipid biosynthetic and metabolic enzymes.
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Affiliation(s)
- Peter J. Harrison
- School of Chemistry
, University of Edinburgh
,
David Brewster Road
, Edinburgh
, EH9 3FJ
, UK
.
| | - Teresa M. Dunn
- Department of Biochemistry and Molecular Biology
, Uniformed Services University
,
Bethesda
, Maryland
20814
, USA
| | - Dominic J. Campopiano
- School of Chemistry
, University of Edinburgh
,
David Brewster Road
, Edinburgh
, EH9 3FJ
, UK
.
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13
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Rossignoli G, Phillips RS, Astegno A, Menegazzi M, Voltattorni CB, Bertoldi M. Phosphorylation of pyridoxal 5'-phosphate enzymes: an intriguing and neglected topic. Amino Acids 2017; 50:205-215. [PMID: 29204749 DOI: 10.1007/s00726-017-2521-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Accepted: 11/29/2017] [Indexed: 12/25/2022]
Abstract
Pyridoxal 5'-phosphate (PLP)-dependent enzymes catalyze a wide range of reactions of amino acids and amines, with the exception of glycogen phosphorylase which exhibits peculiar both substrate preference and chemical mechanism. They represent about 4% of the gene products in eukaryotic cells. Although structure-function investigations regarding these enzymes are copious, their regulation by post-translational modifications is largely unknown. Protein phosphorylation is the most common post-translational modification fundamental in mediating diverse cellular functions. This review aims at summarizing the current knowledge on regulation of PLP enzymes by phosphorylation. Starting from the paradigmatic PLP-dependent glycogen phosphorylase, the first phosphoprotein discovered, we collect data in literature regarding functional phosphorylation events of eleven PLP enzymes belonging to different fold types and discuss the impact of the modification in affecting their activity and localization as well as the implications on the pathogenesis of diseases in which many of these enzymes are involved. The pivotal question is to correlate the structural consequences of phosphorylation among PLP enzymes of different folds with the functional modifications exerted in terms of activity or conformational changes or others. Although the literature shows that the phosphorylation of PLP enzymes plays important roles in mediating diverse cellular functions, our recapitulation of clue findings in the field makes clear that there is still much to be learnt. Besides mass spectrometry-based proteomic analyses, further biochemical and structural studies on purified native proteins are imperative to fully understand and predict how phosphorylation regulates PLP enzymes and to find the relationship between addition of a phosphate moiety and physiological response.
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Affiliation(s)
- Giada Rossignoli
- Department of Neuroscience, Biomedicine and Movement, University of Verona, Strada Le Grazie, 8, 37134, Verona, Italy
| | - Robert S Phillips
- Department of Chemistry, University of Georgia, Athens, GA, 30602, USA.,Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Alessandra Astegno
- Department of Biotechnology, University of Verona, Strada Le Grazie, 15, 37134, Verona, Italy
| | - Marta Menegazzi
- Department of Neuroscience, Biomedicine and Movement, University of Verona, Strada Le Grazie, 8, 37134, Verona, Italy
| | - Carla Borri Voltattorni
- Department of Neuroscience, Biomedicine and Movement, University of Verona, Strada Le Grazie, 8, 37134, Verona, Italy
| | - Mariarita Bertoldi
- Department of Neuroscience, Biomedicine and Movement, University of Verona, Strada Le Grazie, 8, 37134, Verona, Italy.
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14
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Major apoptotic mechanisms and genes involved in apoptosis. Tumour Biol 2016; 37:8471-86. [PMID: 27059734 DOI: 10.1007/s13277-016-5035-9] [Citation(s) in RCA: 362] [Impact Index Per Article: 45.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 03/28/2016] [Indexed: 12/12/2022] Open
Abstract
As much as the cellular viability is important for the living organisms, the elimination of unnecessary or damaged cells has the opposite necessity for the maintenance of homeostasis in tissues, organs and the whole organism. Apoptosis, a type of cell death mechanism, is controlled by the interactions between several molecules and responsible for the elimination of unwanted cells from the body. Apoptosis can be triggered by intrinsically or extrinsically through death signals from the outside of the cell. Any abnormality in apoptosis process can cause various types of diseases from cancer to auto-immune diseases. Different gene families such as caspases, inhibitor of apoptosis proteins, B cell lymphoma (Bcl)-2 family of genes, tumor necrosis factor (TNF) receptor gene superfamily, or p53 gene are involved and/or collaborate in the process of apoptosis. In this review, we discuss the basic features of apoptosis and have focused on the gene families playing critical roles, activation/inactivation mechanisms, upstream/downstream effectors, and signaling pathways in apoptosis on the basis of cancer studies. In addition, novel apoptotic players such as miRNAs and sphingolipid family members in various kind of cancer are discussed.
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15
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Yamane M. Palmitoyl-ceramide accumulation with necrotic cell death in A549 cells, followed by a steep increase in sphinganine content. BIOCHIMIE OPEN 2015; 1:11-27. [PMID: 29632826 PMCID: PMC5889477 DOI: 10.1016/j.biopen.2015.06.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 06/03/2015] [Indexed: 11/29/2022]
Abstract
Ceramides (Cers) have recently been identified as key signaling molecules that mediate biological functions such as cell growth, differentiation, senescence, apoptosis, and autophagy. However, the functions of Cer accumulation in necrotic cell death remain unknown. The aim of this study was to clarify the relationship between Cer accumulation with inhibition of the conversion pathway of Cer and concomitant necrotic cell death. In order to minimize the effect of apoptosis against necrotic cell death, A549 cells having the inhibiting effect of caspase 9 by survivin were used in this study. Consequently, Cer accumulation in A549 cells would likely be associated with a pathway other than the mitochondrial caspase-dependent pathway of apoptosis. Here, we showed that the dual addition of a glucosyl-Cer synthase inhibitor and a ceramidase inhibitor to A549 cell culture induced palmitoyl-Cer accumulation with Cer synthase 5 expression and necrotic cell death with lysosomal rupture together with leakage of cathepsin B/alkalization after 2–3 h, although it is unknown in this study whether the necrotic cell death was caused by the lysosomal rupture. This Cer accumulation was followed by a steep increase in sphinganine base levels via the activation of serine palmitoyltransferase activity brought about by the increase in palmitoyl-coenzyme A concentration as a substrate after 5–6 h. The increase in palmitoyl-coenzyme A concentration was achieved by activation of the fatty acid synthetic pathway from acetyl coenzyme A. Palmitoylceramide accumulation with necrosis is studied. The accumulation is with ceramide synthase 5 expression. The accumulation is followed by high sphinganine levels.
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Key Words
- ([13C16]C16:0-CoA, palmitoyl-13C16 coenzyme A
- 4-HPR, N-(4-hydroxyphenyl)retinamide
- A549 cells
- APCI, atmospheric pressure chemical ionization
- BSA, bovine serum albumin
- C16:0-Cer, palmitoyl-ceramide
- C16:0-CoA, palmitoyl-coenzyme A
- C2:0-CoA, acetyl-coenzyme A
- CHOP, CAAT/enhancer binding protein homologous protein
- CathB, cathepsin B
- Cer, ceramide
- CerS, ceramide synthase
- D-NMAPPD
- D-NMAPPD, N-[(1R,2R)-2-hydroxy-1-(hydroxy-methyl)-2-(4-nitrophenyl)ethyl]tetradecanamide
- DAPI, 4′,6-diamidino-2-phenylindole
- DL-PDMP
- DL-PDMP, DL-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol
- DMEM, Dulbecco's modified Eagle's medium
- DMSO, dimethylsulfoxide
- DTT, dithiothreitol
- ER, endoplasmic reticulum
- ESI, electrospray ionization
- FATP1, fatty acid transport protein 1
- FBS, fetal bovine serum
- GlcCer, glucosylceramide
- IS, internal standard
- L-[2,3,3-D3]Ser, L-serine-2,3,3-D3
- LC3, microtubule-associated protein 1 light chain 3B
- LDH, lactate dehydrogenase
- LMP, lysosomal membrane permeabilization
- Lys, lysosomes
- MAM, mitochondria-associated membrane
- Myriocin, 2-amino-3,4-dihydroxy-2-(hydroxymethyl)-14-oxo-6-eicosenoic acid
- Necrosis
- Palmitoyl-ceramide
- SDS, sodium dodecyl sulfate
- SDS-PAGE, sodium dodecyl sulfate-polyacrylamide gel electrophoresis
- SIM, selected-ion monitoring
- SM, sphingomyelin
- SPT, serine palmitoyltransferase
- SPTLC, SPT-long chain base subunit
- Ser, Serine
- Sphinganine
- [1,2,3,4-13C4]C16:0 acid, palmitic acid-1,2,3,4-13C4
- [2-13C]C2:0 acid, sodium acetate-2-13C
- [D7]d18:0, D-erythro-sphinganine-D7
- [D7]d18:1, D-erythro-sphingosine-D7
- acridine orange, 3,6-Bis(dimethylamino) acridine hydrochloride
- d18:0, sphinganine
- d18:1, sphingosine
- d18:1-[D31]C16:0-Cer, N-palmitoyl [D31]-D-erythro-sphingosine
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Affiliation(s)
- Mototeru Yamane
- Department of Biochemistry, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, Tokyo 160-0023, Japan
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16
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Kitatani K, Taniguchi M, Okazaki T. Role of Sphingolipids and Metabolizing Enzymes in Hematological Malignancies. Mol Cells 2015; 38:482-95. [PMID: 25997737 PMCID: PMC4469906 DOI: 10.14348/molcells.2015.0118] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 05/07/2015] [Indexed: 12/16/2022] Open
Abstract
Sphingolipids such as ceramide, sphingosine-1-phosphate and sphingomyelin have been emerging as bioactive lipids since ceramide was reported to play a role in human leukemia HL-60 cell differentiation and death. Recently, it is well-known that ceramide acts as an inducer of cell death, that sphingomyelin works as a regulator for microdomain function of the cell membrane, and that sphingosine-1-phosphate plays a role in cell survival/proliferation. The lipids are metabolized by the specific enzymes, and each metabolite could be again returned to the original form by the reverse action of the different enzyme or after a long journey of many metabolizing/synthesizing pathways. In addition, the metabolites may serve as reciprocal bio-modulators like the rheostat between ceramide and sphingosine-1-phosphate. Therefore, the change of lipid amount in the cells, the subcellular localization and the downstream signal in a specific subcellular organelle should be clarified to understand the pathobiological significance of sphingolipids when extracellular stimulation induces a diverse of cell functions such as cell death, proliferation and migration. In this review, we focus on how sphingolipids and their metabolizing enzymes cooperatively exert their function in proliferation, migration, autophagy and death of hematopoetic cells, and discuss the way developing a novel therapeutic device through the regulation of sphingolipids for effectively inhibiting cell proliferation and inducing cell death in hematological malignancies such as leukemia, malignant lymphoma and multiple myeloma.
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Affiliation(s)
- Kazuyuki Kitatani
- Tohoku Medical Megabank Organization, Sendai,
Japan
- Department of Obstetrics and Gynecology, Tohoku University Graduate School of Medicine, Tohoku University, Sendai,
Japan
| | - Makoto Taniguchi
- Medical Research Institute, Kanazawa Medical University, Uchinada, Ishikawa 920-0293,
Japan
| | - Toshiro Okazaki
- Medical Research Institute, Kanazawa Medical University, Uchinada, Ishikawa 920-0293,
Japan
- Department of Medicine, Division of Hematology/Immunology, Kanazawa Medical University, Uchinada, Ishikawa 920-0293,
Japan
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17
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Gupta SD, Gable K, Alexaki A, Chandris P, Proia RL, Dunn TM, Harmon JM. Expression of the ORMDLS, modulators of serine palmitoyltransferase, is regulated by sphingolipids in mammalian cells. J Biol Chem 2014; 290:90-8. [PMID: 25395622 DOI: 10.1074/jbc.m114.588236] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The relationship between serine palmitoyltransferase (SPT) activity and ORMDL regulation of sphingolipid biosynthesis was investigated in mammalian HEK293 cells. Each of the three human ORMDLs reduced the increase in long-chain base synthesis seen after overexpression of wild-type SPT or SPT containing the C133W mutation in hLCB1, which produces the non-catabolizable sphingoid base, 1-deoxySa. ORMDL-dependent repression of sphingoid base synthesis occurred whether SPT was expressed as individual subunits or as a heterotrimeric single-chain SPT fusion protein. Overexpression of the single-chain SPT fusion protein under the control of a tetracycline-inducible promoter in stably transfected cells resulted in increased endogenous ORMDL expression. This increase was not transcriptional; there was no significant increase in any of the ORMDL mRNAs. Increased ORMDL protein expression required SPT activity since overexpression of a catalytically inactive SPT with a mutation in hLCB2a had little effect. Significantly, increased ORMDL expression was also blocked by myriocin inhibition of SPT as well as fumonisin inhibition of the ceramide synthases, suggesting that increased expression is a response to a metabolic signal. Moreover, blocking ORMDL induction with fumonisin treatment resulted in significantly greater increases in in vivo SPT activity than was seen when ORMDLs were allowed to increase, demonstrating the physiological significance of this response.
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Affiliation(s)
- Sita D Gupta
- From the Departments of Biochemistry and Molecular Biology and
| | - Kenneth Gable
- From the Departments of Biochemistry and Molecular Biology and
| | - Aikaterini Alexaki
- Genetics of Development and Disease Branch, NIDDK, National Institutes of Health, Bethesda, Maryland 20892
| | - Panagiotis Chandris
- Genetics of Development and Disease Branch, NIDDK, National Institutes of Health, Bethesda, Maryland 20892
| | - Richard L Proia
- Genetics of Development and Disease Branch, NIDDK, National Institutes of Health, Bethesda, Maryland 20892
| | - Teresa M Dunn
- From the Departments of Biochemistry and Molecular Biology and
| | - Jeffrey M Harmon
- Pharmacology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814-4799 and
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18
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Pepin E, Higa A, Schuster-Klein C, Bernard C, Sulpice T, Guardiola B, Chevet E, Alquier T. Deletion of apoptosis signal-regulating kinase 1 (ASK1) protects pancreatic beta-cells from stress-induced death but not from glucose homeostasis alterations under pro-inflammatory conditions. PLoS One 2014; 9:e112714. [PMID: 25383781 PMCID: PMC4226582 DOI: 10.1371/journal.pone.0112714] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 10/14/2014] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Type 2 diabetes is characterized by pancreatic beta-cell dysfunction and is associated with low-grade inflammation. Recent observations suggest that apoptosis signal-regulating kinase 1 (ASK1) is involved in beta-cell death in response to different stressors. In this study, we tested whether ASK1 deficiency protects beta-cells from glucolipotoxic conditions and cytokines treatment or from glucose homeostasis alteration induced by endotoxemia. METHODOLOGY/PRINCIPAL FINDINGS Insulin secretion was neither affected upon shRNA-mediated downregulation of ASK1 in MIN6 cells nor in islets from ASK1-deficient mice. ASK1 silencing in MIN6 cells and deletion in islets did not prevent the deleterious effect of glucolipotoxic conditions or cytokines on insulin secretion. However, it protected MIN6 cells from death induced by ER stress or palmitate and islets from short term caspase activation in response to cytokines. Moreover, endotoxemia induced by LPS infusion increased insulin secretion during hyperglycemic clamps but the response was similar in wild-type and ASK1-deficient mice. Finally, insulin sensitivity in the presence of LPS was not affected by ASK1-deficiency. CONCLUSIONS/SIGNIFICANCE Our study demonstrates that ASK1 is not involved in beta-cell function and dysfunction but controls stress-induced beta-cell death.
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Affiliation(s)
| | - Arisa Higa
- Inserm U1053, Team Endoplasmic Reticulum Stress and Cancer, Université de Bordeaux, Bordeaux, France, 33076
| | | | | | - Thierry Sulpice
- Betagenex Inc, Laval, QC, Canada, H7V5B7
- Physiogenex SAS, Labège, France, 31670
| | | | - Eric Chevet
- Inserm U1053, Team Endoplasmic Reticulum Stress and Cancer, Université de Bordeaux, Bordeaux, France, 33076
| | - Thierry Alquier
- Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), and Departments of Medicine, Biochemistry and Cell Biology and Pathology, Université de Montréal, Montréal, QC, Canada, H3T 1J4
- * E-mail:
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