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Shakeel I, Haider S, Khan S, Ahmed S, Hussain A, Alajmi MF, Chakrabarty A, Afzal M, Imtaiyaz Hassan M. Thymoquinone, artemisinin, and thymol attenuate proliferation of lung cancer cells as Sphingosine kinase 1 inhibitors. Biomed Pharmacother 2024; 177:117123. [PMID: 39004062 DOI: 10.1016/j.biopha.2024.117123] [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: 05/03/2024] [Revised: 07/08/2024] [Accepted: 07/08/2024] [Indexed: 07/16/2024] Open
Abstract
Sphingosine-1-phosphate (S1P) formed via catalytic actions of sphingosine kinase 1 (SphK1) behaves as a pro-survival substance and activates downstream target molecules associated with various pathologies, including initiation, inflammation, and progression of cancer. Here, we aimed to investigate the SphK1 inhibitory potentials of thymoquinone (TQ), Artemisinin (AR), and Thymol (TM) for the therapeutic management of lung cancer. We implemented docking, molecular dynamics (MD) simulations, enzyme inhibition assay, and fluorescence measurement studies to estimate binding affinity and SphK1 inhibitory potential of TQ, AR, and TM. We further investigated the anti-cancer potential of these compounds on non-small cell lung cancer (NSCLC) cell lines (H1299 and A549), followed by estimation of mitochondrial ROS, mitochondrial membrane potential depolarization, and cleavage of DNA by comet assay. Enzyme activity and fluorescence binding studies suggest that TQ, AR, and TM significantly inhibit the activity of SphK1 with IC50 values of 35.52 µM, 42.81 µM, and 53.68 µM, respectively, and have an excellent binding affinity. TQ shows cytotoxic effect and anti-proliferative potentials on H1299 and A549 with an IC50 value of 27.96 µM and 54.43 µM, respectively. Detection of mitochondrial ROS and mitochondrial membrane potential depolarization shows promising TQ-induced oxidative stress on H1299 and A549 cell lines. Comet assay shows promising TQ-induced oxidative DNA damage. In conclusion, TQ, AR, and TM act as potential inhibitors for SphK1, with a strong binding affinity. In addition, the cytotoxicity of TQ is linked to oxidative stress due to mitochondrial ROS generation. Overall, our study suggests that TQ is a promising inhibitor of SphK1 targeting lung cancer therapy.
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Affiliation(s)
- Ilma Shakeel
- Department of Zoology, Aligarh Muslim University, Aligarh, UP 202001, India; Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Shaista Haider
- Department of Life Sciences, School of Natural Sciences, Shiv Nadar Institution of Eminence, Deemed to be University, Gautam Buddha Nagar, UP 201314, India
| | - Shama Khan
- South African Medical Research Council, Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Science, School of Pathology, University of the Witwatersrand, Johannesburg, South Africa
| | - Shahbaz Ahmed
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Afzal Hussain
- Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Mohamed F Alajmi
- Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Anindita Chakrabarty
- Department of Life Sciences, School of Natural Sciences, Shiv Nadar Institution of Eminence, Deemed to be University, Gautam Buddha Nagar, UP 201314, India
| | - Mohammad Afzal
- Department of Zoology, Aligarh Muslim University, Aligarh, UP 202001, India
| | - Md Imtaiyaz Hassan
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India.
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Chen F, Fan Y, Hou J, Liu B, Zhang B, Shang Y, Chang Y, Cao P, Tan K. Integrated analysis identifies TfR1 as a prognostic biomarker which correlates with immune infiltration in breast cancer. Aging (Albany NY) 2021; 13:21671-21699. [PMID: 34518441 PMCID: PMC8457555 DOI: 10.18632/aging.203512] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 08/24/2021] [Indexed: 01/16/2023]
Abstract
Breast cancer (BC) is the most common malignancy with high morbidity and mortality in females worldwide. Emerging evidence indicates that transferrin receptor 1 (TfR1) plays vital roles in regulating cellular iron import. However, the distinct role of TfR1 in BC remains elusive. TfR1 expression was investigated using the TCGA, GEO, TIMER, UALCAN and Oncomine databases. The prognostic potential of TfR1 was evaluated by Kaplan-Meier (KM) plotter and univariate and multivariate Cox regression analyses. Moreover, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and gene set enrichment analysis (GSEA) were used to explore the molecular mechanism of TfR1. The potential link between TfR1 expression and infiltrating abundances of immune cells was examined through the TIMER and CIBERSORT algorithm. The expression of TfR1 was dramatically upregulated in BC tissues. Increased TfR1 expression and decreased methylation levels of TfR1 were strongly correlated with multiple clinicopathological parameters. Elevated TfR1 expression was associated with a poor survival rate in BC patients. The nomogram model further confirmed that TfR1 could act as an independent prognostic biomarker in BC. The results of GO, KEGG and GSEA revealed that TfR1 was closely correlated with multiple signaling pathways and immune responses. Additionally, TfR1 was positively associated with the infiltration abundances of six major immune cells, including CD4+ T cells, CD8+ T cells, B cells, neutrophils, macrophages, and dendritic cells in BC. Interestingly, TfR1 influenced prognosis partially through immune infiltration. These comprehensive bioinformatics analyses suggest that TfR1 is a new independent prognostic biomarker and a potential target for immunotherapy in BC.
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Affiliation(s)
- Fei Chen
- Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, China
| | - Yumei Fan
- Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, China
| | - Jiajie Hou
- Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, China
| | - Bing Liu
- Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, China
| | - Bo Zhang
- Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, China
| | - Yanan Shang
- Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, China
| | - Yanzhong Chang
- Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, China
| | - Pengxiu Cao
- Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, China
| | - Ke Tan
- Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, China
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3
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Xiong Q, Li X, Li W, Chen G, Xiao H, Li P, Wu C. WDR45 Mutation Impairs the Autophagic Degradation of Transferrin Receptor and Promotes Ferroptosis. Front Mol Biosci 2021; 8:645831. [PMID: 34012978 PMCID: PMC8126626 DOI: 10.3389/fmolb.2021.645831] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 04/06/2021] [Indexed: 12/11/2022] Open
Abstract
WDR45 is an autophagy-related protein that involves in the formation of autophagosome. Mutations in WDR45 lead to the impairment of autophagy which is associated with the human β-propeller protein-associated neurodegeneration (BPAN). However, the relationship between autophagy and brain iron accumulation in patients with BPAN remains unclear. Here, we demonstrated that transferrin receptor (TfRC) which is critical for the iron import of cells was degraded via autophagy. TfRC was accumulated after the inhibition of autophagy by treatment with autophagic inhibitor chloroquine or knockdown of ATG2A. The intracellular iron content was increased in cells overexpressing TfRC or mutant WDR45, however, ferritin H (FTH) chain was decreased. Increased TfRC and simultaneously decreased FTH consequently resulted in an elevated level of ferrous iron (Fe2+) which further promoted cell ferroptosis, demonstrated by the increased lipid peroxidation and reactive oxygen species (ROS) and the decreased glutathione peroxidase 4 (GPX4) and cell viability. Taken together, these findings provide a piece of important evidence that WDR45 deficiency impairs autophagic degradation of TfRC, therefore leading to iron accumulation, and the elevated iron promotes ferroptosis which may contribute to the progression of BPAN.
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Affiliation(s)
- Qiuhong Xiong
- Institutes of Biomedical Sciences, Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan, China
| | - Xin Li
- Institutes of Biomedical Sciences, Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan, China
| | - Wenjing Li
- Institutes of Biomedical Sciences, Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan, China
| | - Guangxin Chen
- Institutes of Biomedical Sciences, Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan, China
| | - Han Xiao
- Institutes of Biomedical Sciences, Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan, China
| | - Ping Li
- Institutes of Biomedical Sciences, Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan, China
| | - Changxin Wu
- Institutes of Biomedical Sciences, Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan, China
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Brown RDR, Veerman BEP, Oh J, Tate RJ, Torta F, Cunningham MR, Adams DR, Pyne S, Pyne NJ. A new model for regulation of sphingosine kinase 1 translocation to the plasma membrane in breast cancer cells. J Biol Chem 2021; 296:100674. [PMID: 33865856 PMCID: PMC8135045 DOI: 10.1016/j.jbc.2021.100674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 04/01/2021] [Accepted: 04/14/2021] [Indexed: 01/24/2023] Open
Abstract
The translocation of sphingosine kinase 1 (SK1) to the plasma membrane (PM) is crucial in promoting oncogenesis. We have previously proposed that SK1 exists as both a monomer and dimer in equilibrium, although it is unclear whether these species translocate to the PM via the same or different mechanisms. We therefore investigated the structural determinants involved to better understand how translocation might potentially be targeted for therapeutic intervention. We report here that monomeric WT mouse SK1 (GFP-mSK1) translocates to the PM of MCF-7L cells stimulated with carbachol or phorbol 12-myristate 13-acetate, whereas the dimer translocates to the PM in response to sphingosine-1-phosphate; thus, the equilibrium between the monomer and dimer is sensitive to cellular stimulus. In addition, carbachol and phorbol 12-myristate 13-acetate induced translocation of monomeric GFP-mSK1 to lamellipodia, whereas sphingosine-1-phosphate induced translocation of dimeric GFP-mSK1 to filopodia, suggesting that SK1 regulates different cell biological processes dependent on dimerization. GFP-mSK1 mutants designed to modulate dimerization confirmed this difference in localization. Regulation by the C-terminal tail of SK1 was investigated using GFP-mSK1 truncations. Removal of the last five amino acids (PPEEP) prevented translocation of the enzyme to the PM, whereas removal of the last ten amino acids restored translocation. This suggests that the penultimate five amino acids (SRRGP) function as a translocation brake, which can be released by sequestration of the PPEEP sequence. We propose that these determinants alter the arrangement of N-terminal and C-terminal domains in SK1, leading to unique surfaces that promote differential translocation to the PM.
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Affiliation(s)
- Ryan D R Brown
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, UK
| | - Ben E P Veerman
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, UK
| | - Jeongah Oh
- SLING, Singapore Lipidomics Incubator, Life Sciences Institute and Department of Biochemistry, YLL School of Medicine, National University of Singapore, Singapore, Singapore
| | - Rothwelle J Tate
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, UK
| | - Federico Torta
- SLING, Singapore Lipidomics Incubator, Life Sciences Institute and Department of Biochemistry, YLL School of Medicine, National University of Singapore, Singapore, Singapore
| | - Margaret R Cunningham
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, UK
| | - David R Adams
- School of Engineering & Physical Sciences, Heriot-Watt University, Edinburgh, UK
| | - Susan Pyne
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, UK
| | - Nigel J Pyne
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, UK.
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5
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METTL3-mediated m 6A methylation of SPHK2 promotes gastric cancer progression by targeting KLF2. Oncogene 2021; 40:2968-2981. [PMID: 33758320 DOI: 10.1038/s41388-021-01753-1] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 02/27/2021] [Accepted: 03/08/2021] [Indexed: 02/01/2023]
Abstract
N6-methyladenosine (m6A) RNA methylation is profoundly involved in epigenetic regulation, especially for carcinogenesis and tumor progression. Mounting evidence suggests that methyltransferase METTL3 regulates malignant behaviors of gastric cancer (GC). However, the clinical significance and biological implication of SPHK2 and its related m6A modification in GC remain unclear. In this study, quantitative real-time PCR (qRT-PCR), western blot and immunohistochemistry were utilized to detect the expression profiles and prognostic significance of SPHK2 in GC. Here, we showed that increased SPHK2 was signified a poor prognosis of GC patients. Phosphorylation and ubiquitination assays were used to investigate the possible mechanisms of SPHK2-mediated KLF2 expression. SPHK2 can promote the phosphorylation of KLF2, which triggers the ubiquitination and degradation of KLF2 protein in GC. Methylated RNA immunoprecipitation (MeRIP) was performed to uncover the m6A modification of SPHK2 mRNA. METTL3 promotes translation of SPHK2 mRNA via an m6A-YTHDF1-dependent manner. Functionally, SPHK2 facilitates GC cell proliferation, migration and invasion by inhibiting KLF2 expression. SPHK2/KLF2 regulates the cell proliferation, migration, and invasion induced by METTL3 in GC. Overall, our findings reveal that METTL3-mediated m6A modification of SPHK2 contributes to GC progression, which extends the understanding of the importance m6A methylation in GC and represents a potential target for GC therapy.
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Corral VM, Schultz ER, Eisenstein RS, Connell GJ. Roquin is a major mediator of iron-regulated changes to transferrin receptor-1 mRNA stability. iScience 2021; 24:102360. [PMID: 33898949 PMCID: PMC8058555 DOI: 10.1016/j.isci.2021.102360] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 09/18/2020] [Accepted: 03/23/2021] [Indexed: 11/21/2022] Open
Abstract
Transferrin receptor-1 (TfR1) has essential iron transport and proposed signal transduction functions. Proper TfR1 regulation is a requirement for hematopoiesis, neurological development, and the homeostasis of tissues including the intestine and muscle, while dysregulation is associated with cancers and immunodeficiency. TfR1 mRNA degradation is highly regulated, but the identity of the degradation activity remains uncertain. Here, we show with gene knockouts and siRNA knockdowns that two Roquin paralogs are major mediators of iron-regulated changes to the steady-state TfR1 mRNA level within four different cell types (HAP1, HUVEC, L-M, and MEF). Roquin is demonstrated to destabilize the TfR1 mRNA, and its activity is fully dependent on three hairpin loops within the TfR1 mRNA 3′-UTR that are essential for iron-regulated instability. We further show in L-M cells that TfR1 mRNA degradation does not require ongoing translation, consistent with Roquin-mediated instability. We conclude that Roquin is a major effector of TfR1 mRNA abundance. Roquin is a major mediator of iron-regulated TfR1 mRNA instability Roquin-mediated instability requires three stem loops within the TfR1 3′-UTR Iron-regulated TfR1 mRNA instability can occur in the absence of Regnase-1
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Affiliation(s)
- Victor M Corral
- Department of Pharmacology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Eric R Schultz
- Department of Pharmacology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Richard S Eisenstein
- Department of Nutritional Sciences, University of Wisconsin, Madison, WI 53706, USA
| | - Gregory J Connell
- Department of Pharmacology, University of Minnesota, Minneapolis, MN 55455, USA
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7
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Wang X, Sun Y, Peng X, Naqvi SMAS, Yang Y, Zhang J, Chen M, Chen Y, Chen H, Yan H, Wei G, Hong P, Lu Y. The Tumorigenic Effect of Sphingosine Kinase 1 and Its Potential Therapeutic Target. Cancer Control 2020; 27:1073274820976664. [PMID: 33317322 PMCID: PMC8480355 DOI: 10.1177/1073274820976664] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Sphingosine kinase 1 (SPHK1) regulates cell proliferation and survival by converting sphingosine to the signaling mediator sphingosine 1-phosphate (S1P). SPHK1 is widely overexpressed in most cancers, promoting tumor progression and is associated with clinical prognosis. Numerous studies have explored SPHK1 as a promising target for cancer therapy. However, due to insufficient knowledge of SPHK1 oncogenic mechanisms, its inhibitors’ therapeutic potential in preventing and treating cancer still needs further investigation. In this review, we summarized the metabolic balance regulated by the SPHK1/S1P signaling pathway and highlighted the oncogenic mechanisms of SPHK1 via the upregulation of autophagy, proliferation, and survival, migration, angiogenesis and inflammation, and inhibition of apoptosis. Drug candidates targeting SPHK1 were also discussed at the end. This review provides new insights into the oncogenic effect of SPHK1 and sheds light on the future direction for targeting SPHK1 as cancer therapy.
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Affiliation(s)
- Xianwang Wang
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, Hubei, China
- Laboratory of Oncology, Center for Molecular Medicine, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, Hubei, China
| | - Yong Sun
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, Hubei, China
| | - Xiaochun Peng
- Laboratory of Oncology, Center for Molecular Medicine, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, Hubei, China
| | - Syed Manzar Abbas Shah Naqvi
- Laboratory of Oncology, Center for Molecular Medicine, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, Hubei, China
| | - Yue Yang
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, Hubei, China
| | - Jing Zhang
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, Hubei, China
| | - Meiwen Chen
- Laboratory of Oncology, Center for Molecular Medicine, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, Hubei, China
| | - Yuan Chen
- Laboratory of Oncology, Center for Molecular Medicine, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, Hubei, China
| | - Hongyue Chen
- Laboratory of Oncology, Center for Molecular Medicine, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, Hubei, China
| | - Huizi Yan
- Laboratory of Oncology, Center for Molecular Medicine, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, Hubei, China
| | - Guangliang Wei
- Laboratory of Oncology, Center for Molecular Medicine, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, Hubei, China
| | - Peng Hong
- The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Yingying Lu
- The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
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8
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Pyne NJ, Pyne S. Recent advances in the role of sphingosine 1-phosphate in cancer. FEBS Lett 2020; 594:3583-3601. [PMID: 32969034 DOI: 10.1002/1873-3468.13933] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 09/05/2020] [Accepted: 09/07/2020] [Indexed: 12/18/2022]
Abstract
Sphingosine 1-phosphate (S1P) is a bioactive lipid that binds to a family of G protein-coupled receptors (S1P1-5 ) and intracellular targets, such as HDAC1/2, that are functional in normal and pathophysiologic cell biology. There is a significant role for sphingosine 1-phosphate in cancer underpinning the so-called hallmarks, such as transformation and replicative immortality. In this review, we survey the most recent developments concerning the role of sphingosine 1-phosphate receptors, sphingosine kinase and S1P lyase in cancer and the prognostic indications of these receptors and enzymes in terms of disease-specific survival and recurrence. We also provide evidence for identification of new therapeutic approaches targeting sphingosine 1-phosphate to prevent neovascularisation, to revert aggressive and drug-resistant cancers to more amenable forms sensitive to chemotherapy, and to induce cytotoxicity in cancer cells. Finally, we briefly describe current advances in the development of isoform-specific inhibitors of sphingosine kinases for potential use in the treatment of various cancers, where these enzymes have a predominant role. This review will therefore highlight sphingosine 1-phosphate signalling as a promising translational target for precision medicine in stratified cancer patients.
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Affiliation(s)
- Nigel J Pyne
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK
| | - Susan Pyne
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK
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Alshaker H, Thrower H, Pchejetski D. Sphingosine Kinase 1 in Breast Cancer-A New Molecular Marker and a Therapy Target. Front Oncol 2020; 10:289. [PMID: 32266132 PMCID: PMC7098968 DOI: 10.3389/fonc.2020.00289] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 02/19/2020] [Indexed: 12/31/2022] Open
Abstract
It is now well-established that sphingosine kinase 1 (SK1) plays a significant role in breast cancer development, progression, and spread, whereas SK1 knockdown can reverse these processes. In breast cancer cells and tumors, SK1 was shown to interact with various pathways involved in cell survival and chemoresistance, such as nuclear factor-kappa B (NFκB), Notch, Ras/MAPK, PKC, and PI3K. SK1 is upregulated by estrogen signaling, which, in turn, confers cancer cells with resistance to tamoxifen. Sphingosine-1-phosphate (S1P) produced by SK1 has been linked to tumor invasion and metastasis. Both SK1 and S1P are closely linked to inflammation and adipokine signaling in breast cancer. In human tumors, high SK1 expression has been linked with poorer survival and prognosis. SK1 is upregulated in triple negative tumors and basal-like subtypes. It is often associated with high phosphorylation levels of ERK1/2, SFK, LYN, AKT, and NFκB. Higher tumor SK1 mRNA levels were correlated with poor response to chemotherapy. This review summarizes the up-to-date evidence and discusses the therapeutic potential for the SK1 inhibition in breast cancer, with emphasis on the mechanisms of chemoresistance and combination with other therapies such as gefitinib or docetaxel. We have outlined four key areas for future development, including tumor microenvironment, combination therapies, and nanomedicine. We conclude that SK1 may have a potential as a target for precision medicine, its high expression being a negative prognostic marker in ER-negative breast cancer, as well as a target for chemosensitization therapy.
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Affiliation(s)
- Heba Alshaker
- School of Medicine, University of East Anglia, Norwich, United Kingdom
| | - Hannah Thrower
- Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Dmitri Pchejetski
- School of Medicine, University of East Anglia, Norwich, United Kingdom
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10
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Kelch-like protein 5-mediated ubiquitination of lysine 183 promotes proteasomal degradation of sphingosine kinase 1. Biochem J 2019; 476:3211-3226. [DOI: 10.1042/bcj20190245] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 09/13/2019] [Accepted: 10/14/2019] [Indexed: 01/30/2023]
Abstract
Sphingosine kinase 1 (SK1) is a signalling enzyme that catalyses the phosphorylation of sphingosine to generate the bioactive lipid sphingosine 1-phosphate (S1P). A number of SK1 inhibitors and chemotherapeutics can induce the degradation of SK1, with the loss of this pro-survival enzyme shown to significantly contribute to the anti-cancer properties of these agents. Here we define the mechanistic basis for this degradation of SK1 in response to SK1 inhibitors, chemotherapeutics, and in natural protein turnover. Using an inducible SK1 expression system that enables the degradation of pre-formed SK1 to be assessed independent of transcriptional or translational effects, we found that SK1 was degraded primarily by the proteasome since several proteasome inhibitors blocked SK1 degradation, while lysosome, cathepsin B or pan caspase inhibitors had no effect. Importantly, we demonstrate that this proteasomal degradation of SK1 was enabled by its ubiquitination at Lys183 that appears facilitated by SK1 inhibitor-induced conformational changes in the structure of SK1 around this residue. Furthermore, using yeast two-hybrid screening, we identified Kelch-like protein 5 (KLHL5) as an important protein adaptor linking SK1 to the cullin 3 (Cul3) ubiquitin ligase complex. Notably, knockdown of KLHL5 or Cul3, use of a cullin inhibitor or a dominant-negative Cul3 all attenuated SK1 degradation. Collectively this data demonstrates the KLHL5/Cul3-based E3 ubiquitin ligase complex is important for regulation of SK1 protein stability via Lys183 ubiquitination, in response to SK1 inhibitors, chemotherapy and for normal SK1 protein turnover.
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Vorbach S, Gründer A, Zhou F, Koellerer C, Jutzi JS, Simoni M, Riccetti L, Valk PJ, Sanders MA, Müller-Tidow C, Nofer JR, Pahl HL, Potì F. Enhanced expression of the sphingosine-1-phosphate-receptor-3 causes acute myelogenous leukemia in mice. Leukemia 2019; 34:721-734. [PMID: 31636343 DOI: 10.1038/s41375-019-0577-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 05/20/2019] [Accepted: 06/07/2019] [Indexed: 12/19/2022]
Abstract
Acute myeloid leukemia (AML) carries a 10-100 fold lower mutational burden than other neoplastic entities. Mechanistic explanations for why a low number of mutations suffice to induce leukemogenesis are therefore required. Here we demonstrate that transgenic overexpression of the wild type sphingosine-1-phosphate receptor 3 (S1P3) in murine hematopoietic stem cells is sufficient to induce a transplantable myeloid leukemia. In contrast, S1P3 expression in more mature compartments does not cause malignant transformation. Treatment with the sphingosine phosphate receptor modulator Fingolimod, which prevents receptor signaling, normalized peripheral blood cell counts and reduced spleen sizes in S1P3 expressing mice. Gene expression analyses in AML patients revealed elevated S1P3 expression specifically in two molecular subclasses. Our data suggest a previously unrecognized contribution of wild type S1P3 signaling to leukemogenesis that warrants the exploration of S1P3 antagonists in preclinical AML models.
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Affiliation(s)
- Samuel Vorbach
- Department of Medicine I, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany
| | - Albert Gründer
- Department of Medicine I, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany
| | - Fengbiao Zhou
- Department of Medicine, Hematology, Oncology and Rheumatology, University Hospital Heidelberg, 69120, Heidelberg, Germany
| | - Christoph Koellerer
- Department of Medicine I, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany
| | - Jonas S Jutzi
- Department of Medicine I, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany
| | - Manuela Simoni
- Dept. of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Via Giardini 1355, Modena, Italy
| | - Laura Riccetti
- Dept. of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Via Giardini 1355, Modena, Italy
| | - Peter J Valk
- Department of Hematology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Mathijs A Sanders
- Department of Hematology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Carsten Müller-Tidow
- Department of Medicine, Hematology, Oncology and Rheumatology, University Hospital Heidelberg, 69120, Heidelberg, Germany
| | - Jerzy-Roch Nofer
- Institute of Clinical Chemistry and Laboratory Medicine, University Medical Center Hamburg-Eppendorf, 20251, Hamburg, Germany
| | - Heike L Pahl
- Department of Medicine I, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany.
| | - Francesco Potì
- Dept. of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Via Giardini 1355, Modena, Italy.,Department of Medicine and Surgery-Unit of Neurosciences, University of Parma, Via Volturno 39/F, 43125, Parma, Italy
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12
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Alshaker H, Wang Q, Brewer D, Pchejetski D. Transcriptome-Wide Effects of Sphingosine Kinases Knockdown in Metastatic Prostate and Breast Cancer Cells: Implications for Therapeutic Targeting. Front Pharmacol 2019; 10:303. [PMID: 30971929 PMCID: PMC6445839 DOI: 10.3389/fphar.2019.00303] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 03/11/2019] [Indexed: 12/18/2022] Open
Abstract
Sphingosine kinases 1 and 2 (SK1 and SK2) are proto-oncogenic isozymes expressed in many human tumors and associated with chemoresistance and poor prognosis. They are well-recognized therapy targets and their inhibition was shown to induce tumor volume reduction and chemosensitization in multiple cancer models. Oncogenic signaling is extremely complex and often cross-regulated. Designing molecular therapies and their combinations requires rational approaches to avoid redundant targeting or developing resistance. In this study, we have performed RNA transcriptome microarray analysis of two breast and two prostate metastatic cancer cell lines treated with siRNAs targeting SK1 or SK2. In prostate cancer cell lines SK1 knockdown (KD) has significantly changed expression of several genes including downregulation of NSUN2, G3BP2 and upregulation of ETS1. SK2 KD also affected expression of multiple genes including downregulation of CAPZA1 NSUN3 and ADPGK and upregulation of VDAC1, IBTK, ETS1, and MKNK2. Similarly, in breast cancer cells SK1 KD led to downregulation of NSUN2, NFATC3, CDK2, and G3BP2 and upregulation of GTF2B, TTC17, and RAB23. SK2 KD in breast cancer cells has decreased expression of ITGAV and CAPZA1 and increased expression of GTF2B and ST13. Gene-set enrichment analysis of known biochemical pathways showed that in prostate and breast cell lines SKs KD have altered multiple pathways. SK1 KD altered chromatin assembly, regulation of G1/S transition and mitosis, Wnt and MAP kinase signaling and cell motility. SK2 KD altered RAS protein signal transduction, regulation of MAP kinase and serine/threonine kinase activity, cell motility, small GTPase mediated signal transduction and phosphatidylinositol 3-kinase (PI3K) signaling. Through genome-wide microarray analysis, we have identified important molecular pathways affected by SK1 and SK2 KD. It appears that while KD of both genes leads to a decrease in individual pro-tumorigenic genes, there is a universal cellular response resulting in upregulation of several known pro-survival and pro-tumorigenic pathways such as MAPK, RAS, and PI3K, which may mediate cancer resistance to anti-SKs therapies. Our data point out to the potential advantage of certain molecular therapy combinations in targeting prostate and breast cancer. Further signaling studies are required to confirm the individual involvement of identified pathways.
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Affiliation(s)
- Heba Alshaker
- School of Medicine, University of East Anglia, Norwich, United Kingdom.,Department of Pharmacology and Biomedical Sciences, Faculty of Pharmacy and Medical Sciences, University of Petra, Amman, Jordan
| | - Qi Wang
- School of Medicine, University of East Anglia, Norwich, United Kingdom
| | - Daniel Brewer
- School of Medicine, University of East Anglia, Norwich, United Kingdom.,Earlham Institute, Norwich, United Kingdom
| | - Dmitri Pchejetski
- School of Medicine, University of East Anglia, Norwich, United Kingdom
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13
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El Buri A, Adams DR, Smith D, Tate RJ, Mullin M, Pyne S, Pyne NJ. The sphingosine 1-phosphate receptor 2 is shed in exosomes from breast cancer cells and is N-terminally processed to a short constitutively active form that promotes extracellular signal regulated kinase activation and DNA synthesis in fibroblasts. Oncotarget 2018; 9:29453-29467. [PMID: 30034630 PMCID: PMC6047680 DOI: 10.18632/oncotarget.25658] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 06/04/2018] [Indexed: 12/21/2022] Open
Abstract
We demonstrate here that the G protein-coupled receptor (GPCR), sphingosine 1-phosphate receptor 2 (S1P2, Mr = 40 kDa) is shed in hsp70+ and CD63+ containing exosomes from MDA-MB-231 breast cancer cells. The receptor is taken up by fibroblasts, where it is N-terminally processed to a shorter form (Mr = 36 kDa) that appears to be constitutively active and able to stimulate the extracellular signal regulated kinase-1/2 (ERK-1/2) pathway and DNA synthesis. An N-terminally truncated construct of S1P2, which may correspond to the processed form of the receptor generated in fibroblasts, was found to be constitutively active when over-expressed in HEK293 cells. Analysis based on the available crystal structure of the homologous S1P1 receptor suggests that, in the inactive-state, the N-terminus of S1P2 may tension TM1 so as to maintain a compressive action on TM7. This in turn may stabilise a closed basal state interface between the intracellular ends of TM7 and TM6. Cleavage and removal of the S1P2 N-terminal peptide is postulated to facilitate relaxation of TM1 and accompanying separation of TM6 and TM7. The latter transition is one of the key elements of G protein engagement and is required to open the intracellular coupling interface beneath the GPCR helix bundle. Therefore, removal at the N-terminus of S1P2 is likely to enhance G protein coupling. These findings provide the first evidence that S1P2 is released from breast cancer cells in exosomes and is processed by fibroblasts to promote ERK signaling and proliferation of these cells.
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Affiliation(s)
- Ashref El Buri
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, UK
| | - David R Adams
- School of Engineering & Physical Sciences, Heriot-Watt University, Edinburgh, Scotland, UK
| | - Douglas Smith
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, UK
| | - Rothwelle J Tate
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, UK
| | - Margaret Mullin
- Electron Microscopy Facility, School of Life Sciences, MVLS, Joseph Black Building, University of Glasgow, Glasgow, Scotland, UK
| | - Susan Pyne
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, UK
| | - Nigel J Pyne
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, UK
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14
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Neubauer HA, Pham DH, Zebol JR, Moretti PAB, Peterson AL, Leclercq TM, Chan H, Powell JA, Pitman MR, Samuel MS, Bonder CS, Creek DJ, Gliddon BL, Pitson SM. An oncogenic role for sphingosine kinase 2. Oncotarget 2018; 7:64886-64899. [PMID: 27588496 PMCID: PMC5323123 DOI: 10.18632/oncotarget.11714] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 08/25/2016] [Indexed: 01/02/2023] Open
Abstract
While both human sphingosine kinases (SK1 and SK2) catalyze the generation of the pleiotropic signaling lipid sphingosine 1-phosphate, these enzymes appear to be functionally distinct. SK1 has well described roles in promoting cell survival, proliferation and neoplastic transformation. The roles of SK2, and its contribution to cancer, however, are much less clear. Some studies have suggested an anti-proliferative/pro-apoptotic function for SK2, while others indicate it has a pro-survival role and its inhibition can have anti-cancer effects. Our analysis of gene expression data revealed that SK2 is upregulated in many human cancers, but only to a small extent (up to 2.5-fold over normal tissue). Based on these findings, we examined the effect of different levels of cellular SK2 and showed that high-level overexpression reduced cell proliferation and survival, and increased cellular ceramide levels. In contrast, however, low-level SK2 overexpression promoted cell survival and proliferation, and induced neoplastic transformation in vivo. These findings coincided with decreased nuclear localization and increased plasma membrane localization of SK2, as well as increases in extracellular S1P formation. Hence, we have shown for the first time that SK2 can have a direct role in promoting oncogenesis, supporting the use of SK2-specific inhibitors as anti-cancer agents.
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Affiliation(s)
- Heidi A Neubauer
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia, Australia.,School of Biological Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - Duyen H Pham
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia, Australia.,School of Biological Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - Julia R Zebol
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia, Australia
| | - Paul A B Moretti
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia, Australia
| | - Amanda L Peterson
- Monash Institute of Pharmaceutical Science, Monash University, Parkville, Victoria, Australia
| | - Tamara M Leclercq
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia, Australia
| | - Huasheng Chan
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia, Australia.,School of Biological Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - Jason A Powell
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia, Australia.,School of Medicine, University of Adelaide, Adelaide, South Australia, Australia
| | - Melissa R Pitman
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia, Australia
| | - Michael S Samuel
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia, Australia.,School of Medicine, University of Adelaide, Adelaide, South Australia, Australia
| | - Claudine S Bonder
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia, Australia.,School of Biological Sciences, University of Adelaide, Adelaide, South Australia, Australia.,School of Medicine, University of Adelaide, Adelaide, South Australia, Australia
| | - Darren J Creek
- Monash Institute of Pharmaceutical Science, Monash University, Parkville, Victoria, Australia
| | - Briony L Gliddon
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia, Australia
| | - Stuart M Pitson
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia, Australia.,School of Biological Sciences, University of Adelaide, Adelaide, South Australia, Australia.,School of Medicine, University of Adelaide, Adelaide, South Australia, Australia
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15
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Putzbach W, Gao QQ, Patel M, van Dongen S, Haluck-Kangas A, Sarshad AA, Bartom ET, Kim KYA, Scholtens DM, Hafner M, Zhao JC, Murmann AE, Peter ME. Many si/shRNAs can kill cancer cells by targeting multiple survival genes through an off-target mechanism. eLife 2017; 6. [PMID: 29063830 PMCID: PMC5655136 DOI: 10.7554/elife.29702] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Accepted: 09/13/2017] [Indexed: 12/27/2022] Open
Abstract
Over 80% of multiple-tested siRNAs and shRNAs targeting CD95 or CD95 ligand (CD95L) induce a form of cell death characterized by simultaneous activation of multiple cell death pathways preferentially killing transformed and cancer stem cells. We now show these si/shRNAs kill cancer cells through canonical RNAi by targeting the 3’UTR of critical survival genes in a unique form of off-target effect we call DISE (death induced by survival gene elimination). Drosha and Dicer-deficient cells, devoid of most miRNAs, are hypersensitive to DISE, suggesting cellular miRNAs protect cells from this form of cell death. By testing 4666 shRNAs derived from the CD95 and CD95L mRNA sequences and an unrelated control gene, Venus, we have identified many toxic sequences - most of them located in the open reading frame of CD95L. We propose that specific toxic RNAi-active sequences present in the genome can kill cancer cells. Cells store their genetic code within molecules of DNA. Some of this information will be copied into chemically similar molecules called RNAs, from which the sequence of letters in the genetic code can be translated to build proteins. However, these messenger RNAs are not the only RNA molecules that cells can make. MicroRNAs are other short pieces of RNA that closely match sequences in parts of certain messenger RNAs. The messenger RNAs targeted by microRNAs are broken down inside the cell, which reduces how much protein can be produced from them. Since its discovery, scientists have exploited this process – called RNA interference (or RNAi for short) – and designed microRNA-like small interfering RNAs (siRNAs) to target particular messenger RNAs and decrease the levels of the corresponding proteins in countless experiments. Two proteins that have been studied in RNAi experiments are CD95 and its interaction partner CD95L. Both of these proteins are important in human cancer cells, and targeting them via RNAi killed cancer cells in an unknown mechanism that the cancer cells were unable to resist. RNAi experiments are designed to be specific, but sometimes they can accidently target other non-target messenger RNAs. Putzbach, Gao, Patel et al. have now analyzed all of the siRNAs that can be made from the messenger RNAs for CD95 and CD95L to mediate RNAi in cancer cells. This revealed that several messenger RNAs, other than those for CD95 and CD95L, were unintentionally being targeted, including many that code for proteins that cells need to survive. Further examination of the messenger RNA for CD95 and CD95L showed that they contain short sequences that are similar to those in the messenger RNAs of the genes that encode these survival proteins. Putzbach et al. were able to study and then predict which siRNA sequences would be toxic to cancer cells. These findings indicate that an RNAi off-target effect may actually be used to kill cancer cells. Future studies will determine whether this effect could be exploited to shrink tumors in animal models of cancer. If successful, this in turn could lead to new treatments for cancer patients.
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Affiliation(s)
- William Putzbach
- Division of Hematology and Oncology, Department of Medicine, Northwestern University, Chicago, United States
| | - Quan Q Gao
- Division of Hematology and Oncology, Department of Medicine, Northwestern University, Chicago, United States
| | - Monal Patel
- Division of Hematology and Oncology, Department of Medicine, Northwestern University, Chicago, United States
| | - Stijn van Dongen
- European Bioinformatics Institute (EMBL-EBI), Cambridge, United Kingdom
| | - Ashley Haluck-Kangas
- Division of Hematology and Oncology, Department of Medicine, Northwestern University, Chicago, United States
| | - Aishe A Sarshad
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, United States
| | - Elizabeth T Bartom
- Department of Biochemistry and Molecular Genetics, Northwestern University, Chicago, United States
| | - Kwang-Youn A Kim
- Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, United States
| | - Denise M Scholtens
- Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, United States
| | - Markus Hafner
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, United States
| | - Jonathan C Zhao
- Division of Hematology and Oncology, Department of Medicine, Northwestern University, Chicago, United States
| | - Andrea E Murmann
- Division of Hematology and Oncology, Department of Medicine, Northwestern University, Chicago, United States
| | - Marcus E Peter
- Division of Hematology and Oncology, Department of Medicine, Northwestern University, Chicago, United States.,Department of Biochemistry and Molecular Genetics, Northwestern University, Chicago, United States
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16
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Pyne NJ, El Buri A, Adams DR, Pyne S. Sphingosine 1-phosphate and cancer. Adv Biol Regul 2017; 68:97-106. [PMID: 28942351 DOI: 10.1016/j.jbior.2017.09.006] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 09/13/2017] [Accepted: 09/13/2017] [Indexed: 01/08/2023]
Abstract
The bioactive lipid, sphingosine 1-phosphate (S1P) is produced by phosphorylation of sphingosine and this is catalysed by two sphingosine kinase isoforms (SK1 and SK2). Here we discuss structural functional aspects of SK1 (which is a dimeric quaternary enzyme) that relate to coordinated coupling of membrane association with phosphorylation of Ser225 in the 'so-called' R-loop, catalytic activity and protein-protein interactions (e.g. TRAF2, PP2A and Gq). S1P formed by SK1 at the plasma-membrane is released from cells via S1P transporters to act on S1P receptors to promote tumorigenesis. We discuss here an additional novel mechanism that can operate between cancer cells and fibroblasts and which involves the release of the S1P receptor, S1P2 in exosomes from breast cancer cells that regulates ERK-1/2 signalling in fibroblasts. This novel mechanism of signalling might provide an explanation for the role of S1P2 in promoting metastasis of cancer cells and which is dependent on the micro-environmental niche.
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Affiliation(s)
- Nigel J Pyne
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral St, Glasgow, G4 0RE, Scotland, UK.
| | - Ashref El Buri
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral St, Glasgow, G4 0RE, Scotland, UK
| | - David R Adams
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, Scotland, UK
| | - Susan Pyne
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral St, Glasgow, G4 0RE, Scotland, UK
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17
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Khiroya H, Moore JS, Ahmad N, Kay J, Woolnough K, Langman G, Ismail I, Naidu B, Tselepis C, Turner AM. IRP2 as a potential modulator of cell proliferation, apoptosis and prognosis in nonsmall cell lung cancer. Eur Respir J 2017; 49:1600711. [PMID: 28404645 DOI: 10.1183/13993003.00711-2016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 12/20/2016] [Indexed: 01/10/2023]
Abstract
IREB2 is a gene that produces iron regulatory protein 2 (IRP2), which is critical to intracellular iron homeostasis and which relates to the rate of cellular proliferation. IREB2 lies in a lung cancer susceptibility locus. The aims were to assess 1) the relationship between iron loading, cell proliferation and IRP2 expression in lung cancer; 2) the potential of iron related pathways as therapeutic targets; and 3) the relevance of IRP2 in operated lung cancer patients.Cells of two nonsmall cell cancer (NSCLC) lines and primary bronchial epithelial cells (PBECs) were cultured with and without iron; and proliferation, apoptosis and migration were assessed. Reverse transcriptase PCR and Western blot were used to assess expression of iron homeostasis genes/proteins. Iron chelation and knockdown of IREB2 were used in vitro to explore therapeutics. A cohort of operated NSCLC patients was studied for markers of systemic iron status, tumour IRP2 staining and survival.Iron loading caused cell proliferation in cancer cell lines, which were less able to regulate IREB2 expression than PBECs. Iron chelation resulted in a return of proliferation rates to baseline levels; knockdown of IREB2 had a similar effect. IRP2-positive tumours were larger (p=0.045) and higher percentage staining related to poorer survival (p=0.079).Loss of iron regulation represents a poor prognostic marker in lung cancer.
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Affiliation(s)
- Heena Khiroya
- University of Birmingham, Birmingham, UK
- Both authors contributed equally
| | - Jasbir S Moore
- University of Birmingham, Birmingham, UK
- Both authors contributed equally
| | | | - Jamie Kay
- Barts and the London School of Medicine and Dentistry, London, UK
| | | | | | - Iyad Ismail
- Heart of England NHS Foundation Trust, Birmingham, UK
| | - Babu Naidu
- University of Birmingham, Birmingham, UK
- Heart of England NHS Foundation Trust, Birmingham, UK
| | | | - Alice M Turner
- University of Birmingham, Birmingham, UK
- Heart of England NHS Foundation Trust, Birmingham, UK
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18
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Targeting sphingosine kinase 1 induces MCL1-dependent cell death in acute myeloid leukemia. Blood 2016; 129:771-782. [PMID: 27956387 DOI: 10.1182/blood-2016-06-720433] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 11/30/2016] [Indexed: 12/21/2022] Open
Abstract
Acute myeloid leukemia (AML) is an aggressive malignancy where despite improvements in conventional chemotherapy and bone marrow transplantation, overall survival remains poor. Sphingosine kinase 1 (SPHK1) generates the bioactive lipid sphingosine 1-phosphate (S1P) and has established roles in tumor initiation, progression, and chemotherapy resistance in a wide range of cancers. The role and targeting of SPHK1 in primary AML, however, has not been previously investigated. Here we show that SPHK1 is overexpressed and constitutively activated in primary AML patient blasts but not in normal mononuclear cells. Subsequent targeting of SPHK1 induced caspase-dependent cell death in AML cell lines, primary AML patient blasts, and isolated AML patient leukemic progenitor/stem cells, with negligible effects on normal bone marrow CD34+ progenitors from healthy donors. Furthermore, administration of SPHK1 inhibitors to orthotopic AML patient-derived xenografts reduced tumor burden and prolonged overall survival without affecting murine hematopoiesis. SPHK1 inhibition was associated with reduced survival signaling from S1P receptor 2, resulting in selective downregulation of the prosurvival protein MCL1. Subsequent analysis showed that the combination of BH3 mimetics with either SPHK1 inhibition or S1P receptor 2 antagonism triggered synergistic AML cell death. These results support the notion that SPHK1 is a bona fide therapeutic target for the treatment of AML.
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19
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Mirfazeli ES, Marashi SA, Kalantari S. In silico prediction of specific pathways that regulate mesangial cell proliferation in IgA nephropathy. Med Hypotheses 2016; 97:38-45. [PMID: 27876127 DOI: 10.1016/j.mehy.2016.10.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 09/28/2016] [Accepted: 10/19/2016] [Indexed: 11/30/2022]
Abstract
IgA nephropathy is one of the most common forms of primary glomerulonephritis worldwide leading to end-stage renal disease. Proliferation of mesangial cells, i.e., the multifunctional cells located in the intracapillary region of glomeruli, after IgA- dominant immune deposition is the major histologic feature in IgA nephropathy. In spite of several studies on molecular basis of proliferation in these cells, specific pathways responsible for regulation of proliferation are still to be discovered. In this study, we predicted a specific signaling pathway started from transferrin receptor (TFRC), a specific IgA1 receptor on mesangial cells, toward a set of proliferation-related proteins. The final constructed subnetwork was presented after filtration and evaluation. The results suggest that estrogen receptor (ESR1) as a hub protein in the significant subnetwork has an important role in the mesangial cell proliferation and is a potential target for IgA nephropathy therapy. In conclusion, this study suggests a novel hypothesis for the mechanism of pathogenesis in IgA nephropathy and is a reasonable start point for the future experimental studies on mesangial proliferation process in this disease.
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Affiliation(s)
| | - Sayed-Amir Marashi
- Department of Biotechnology, College of Science, University of Tehran, Tehran, Iran
| | - Shiva Kalantari
- Chronic Kidney Disease Research Center (CKDRC), Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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20
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Aveic S, Tonini GP. Resistance to receptor tyrosine kinase inhibitors in solid tumors: can we improve the cancer fighting strategy by blocking autophagy? Cancer Cell Int 2016; 16:62. [PMID: 27486382 PMCID: PMC4970224 DOI: 10.1186/s12935-016-0341-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 07/25/2016] [Indexed: 12/19/2022] Open
Abstract
A growing field of evidence suggests the involvement of oncogenic receptor tyrosine kinases (RTKs) in the transformation of malignant cells. Constitutive and abnormal activation of RTKs may occur in tumors either through hyperactivation of mutated RTKs or via functional upregulation by RTK-coding gene amplification. In several types of cancer prognosis and therapeutic responses were found to be associated with deregulated activation of one or more RTKs. Therefore, targeting various RTKs remains a significant challenge in the treatment of patients with diverse malignancies. However, a frequent issue with the use of RTK inhibitors is drug resistance. Autophagy activation during treatment with RTK inhibitors has been commonly observed as an obstacle to more efficacious therapy and has been associated with the limited efficacy of RTK inhibitors. In the present review, we discuss autophagy activation after the administration of RTK inhibitors and summarize the achievements of combination RTK/autophagy inhibitor therapy in overcoming the reported resistance to RTK inhibitors in a growing number of cancers.
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Affiliation(s)
- Sanja Aveic
- Neuroblastoma Laboratory, Pediatric Research Institute-Città della Speranza, Padua, Italy
| | - Gian Paolo Tonini
- Neuroblastoma Laboratory, Pediatric Research Institute-Città della Speranza, Padua, Italy
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21
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Ryslik GA, Cheng Y, Modis Y, Zhao H. Leveraging protein quaternary structure to identify oncogenic driver mutations. BMC Bioinformatics 2016; 17:137. [PMID: 27001666 PMCID: PMC4802602 DOI: 10.1186/s12859-016-0963-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 02/18/2016] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Identifying key "driver" mutations which are responsible for tumorigenesis is critical in the development of new oncology drugs. Due to multiple pharmacological successes in treating cancers that are caused by such driver mutations, a large body of methods have been developed to differentiate these mutations from the benign "passenger" mutations which occur in the tumor but do not further progress the disease. Under the hypothesis that driver mutations tend to cluster in key regions of the protein, the development of algorithms that identify these clusters has become a critical area of research. RESULTS We have developed a novel methodology, QuartPAC (Quaternary Protein Amino acid Clustering), that identifies non-random mutational clustering while utilizing the protein quaternary structure in 3D space. By integrating the spatial information in the Protein Data Bank (PDB) and the mutational data in the Catalogue of Somatic Mutations in Cancer (COSMIC), QuartPAC is able to identify clusters which are otherwise missed in a variety of proteins. The R package is available on Bioconductor at: http://bioconductor.jp/packages/3.1/bioc/html/QuartPAC.html . CONCLUSION QuartPAC provides a unique tool to identify mutational clustering while accounting for the complete folded protein quaternary structure.
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Affiliation(s)
- Gregory A. Ryslik
- />Department of Biostatistics, Yale School of Public Health, New Haven, CT USA
| | - Yuwei Cheng
- />Program of Computational Biology and Bioinformatics, Yale University, New Haven, CT USA
| | - Yorgo Modis
- />Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH UK
| | - Hongyu Zhao
- />Department of Biostatistics, Yale School of Public Health, New Haven, CT USA
- />Program of Computational Biology and Bioinformatics, Yale University, New Haven, CT USA
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Pyne S, Adams DR, Pyne NJ. Sphingosine 1-phosphate and sphingosine kinases in health and disease: Recent advances. Prog Lipid Res 2016; 62:93-106. [PMID: 26970273 DOI: 10.1016/j.plipres.2016.03.001] [Citation(s) in RCA: 141] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 03/07/2016] [Accepted: 03/08/2016] [Indexed: 12/24/2022]
Abstract
Sphingosine kinases (isoforms SK1 and SK2) catalyse the formation of a bioactive lipid, sphingosine 1-phosphate (S1P). S1P is a well-established ligand of a family of five S1P-specific G protein coupled receptors but also has intracellular signalling roles. There is substantial evidence to support a role for sphingosine kinases and S1P in health and disease. This review summarises recent advances in the area in relation to receptor-mediated signalling by S1P and novel intracellular targets of this lipid. New evidence for a role of each sphingosine kinase isoform in cancer, the cardiovascular system, central nervous system, inflammation and diabetes is discussed. There is continued research to develop isoform selective SK inhibitors, summarised here. Analysis of the crystal structure of SK1 with the SK1-selective inhibitor, PF-543, is used to identify residues that could be exploited to improve selectivity in SK inhibitor development for future therapeutic application.
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Affiliation(s)
- Susan Pyne
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral St, Glasgow, G4 0RE, Scotland, UK.
| | - David R Adams
- School of Engineering & Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, Scotland, UK.
| | - Nigel J Pyne
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral St, Glasgow, G4 0RE, Scotland, UK.
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Clarke JN, Davies LK, Calvert JK, Gliddon BL, Shujari WHA, Aloia AL, Helbig KJ, Beard MR, Pitson SM, Carr JM. Reduction in sphingosine kinase 1 influences the susceptibility to dengue virus infection by altering antiviral responses. J Gen Virol 2015; 97:95-109. [PMID: 26541871 DOI: 10.1099/jgv.0.000334] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Sphingosine kinase (SK) 1 is a host kinase that enhances some viral infections. Here we investigated the ability of SK1 to modulate dengue virus (DENV) infection in vitro. Overexpression of SK1 did not alter DENV infection; however, targeting SK1 through chemical inhibition resulted in reduced DENV RNA and infectious virus release. DENV infection of SK1⁻/ ⁻ murine embryonic fibroblasts (MEFs) resulted in inhibition of infection in an immortalized line (iMEF) but enhanced infection in primary MEFs (1°MEFs). Global cellular gene expression profiles showed expected innate immune mRNA changes in DENV-infected WT but no induction of these responses in SK1⁻/⁻ iMEFs. Reverse transciption PCR demonstrated a low-level induction of IFN-β and poor induction of mRNA for the interferon-stimulated genes (ISGs) viperin, IFIT1 and CXCL10 in DENV-infected SK1⁻/⁻ compared with WT iMEFs. Similarly, reduced induction of ISGs was observed in SK1⁻/⁻ 1°MEFs, even in the face of high-level DENV replication. In both iMEFs and 1°MEFs, DENV infection induced production of IFN-β protein. Additionally, higher basal levels of antiviral factors (IRF7, CXCL10 and OAS1) were observed in uninfected SK1⁻/⁻ iMEFs but not 1°MEFs. This suggests that, in this single iMEF line, lack of SK1 upregulates the basal levels of factors that may protect cells against DENV infection. More importantly, regardless of the levels of DENV replication, all cells that lacked SK1 produced IFN-β but were refractory to induction of ISGs such as viperin, IFIT1 and CXCL10. Based on these findings, we propose new roles for SK1 in affecting innate responses that regulate susceptibility to DENV infection.
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Affiliation(s)
- Jennifer N Clarke
- Microbiology and Infectious Diseases, School of Medicine, Flinders University, Bedford Park, Adelaide, South Australia 5042, Australia
| | - Lorena K Davies
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia 5000, Australia
| | - Julie K Calvert
- Microbiology and Infectious Diseases, School of Medicine, Flinders University, Bedford Park, Adelaide, South Australia 5042, Australia
| | - Briony L Gliddon
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia 5000, Australia
| | - Wisam H Al Shujari
- Microbiology and Infectious Diseases, School of Medicine, Flinders University, Bedford Park, Adelaide, South Australia 5042, Australia
| | - Amanda L Aloia
- Microbiology and Infectious Diseases, School of Medicine, Flinders University, Bedford Park, Adelaide, South Australia 5042, Australia
| | - Karla J Helbig
- School of Molecular and Biomedical Science, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Michael R Beard
- School of Molecular and Biomedical Science, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Stuart M Pitson
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia 5000, Australia
| | - Jillian M Carr
- Microbiology and Infectious Diseases, School of Medicine, Flinders University, Bedford Park, Adelaide, South Australia 5042, Australia
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Noncanonical role of transferrin receptor 1 is essential for intestinal homeostasis. Proc Natl Acad Sci U S A 2015; 112:11714-9. [PMID: 26324903 DOI: 10.1073/pnas.1511701112] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Transferrin receptor 1 (Tfr1) facilitates cellular iron uptake through receptor-mediated endocytosis of iron-loaded transferrin. It is expressed in the intestinal epithelium but not involved in dietary iron absorption. To investigate its role, we inactivated the Tfr1 gene selectively in murine intestinal epithelial cells. The mutant mice had severe disruption of the epithelial barrier and early death. There was impaired proliferation of intestinal epithelial cell progenitors, aberrant lipid handling, increased mRNA expression of stem cell markers, and striking induction of many genes associated with epithelial-to-mesenchymal transition. Administration of parenteral iron did not improve the phenotype. Surprisingly, however, enforced expression of a mutant allele of Tfr1 that is unable to serve as a receptor for iron-loaded transferrin appeared to fully rescue most animals. Our results implicate Tfr1 in homeostatic maintenance of the intestinal epithelium, acting through a role that is independent of its iron-uptake function.
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Gu Y, Shea J, Slattum G, Firpo MA, Alexander M, Mulvihill SJ, Golubovskaya VM, Rosenblatt J. Defective apical extrusion signaling contributes to aggressive tumor hallmarks. eLife 2015; 4:e04069. [PMID: 25621765 PMCID: PMC4337653 DOI: 10.7554/elife.04069] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 01/22/2015] [Indexed: 12/12/2022] Open
Abstract
When epithelia become too crowded, some cells are extruded that later die. To extrude, a cell produces the lipid, Sphingosine 1-Phosphate (S1P), which activates S1P2 receptors in neighboring cells that seamlessly squeeze the cell out of the epithelium. Here, we find that extrusion defects can contribute to carcinogenesis and tumor progression. Tumors or epithelia lacking S1P2 cannot extrude cells apically and instead form apoptotic-resistant masses, possess poor barrier function, and shift extrusion basally beneath the epithelium, providing a potential mechanism for cell invasion. Exogenous S1P2 expression is sufficient to rescue apical extrusion, cell death, and reduce orthotopic pancreatic tumors and their metastases. Focal Adhesion Kinase (FAK) inhibitor can bypass extrusion defects and could, therefore, target pancreatic, lung, and colon tumors that lack S1P2 without affecting wild-type tissue. DOI:http://dx.doi.org/10.7554/eLife.04069.001 Epithelial cells cover the surface of our bodies, line our lungs, stomach and intestines and serve as a protective layer around other organs. If too many epithelial cells die and are not replaced, this protective layer may erode and lead to organ damage. However, if too many new cells grow, tumors can form. One process that helps to maintain the right number of epithelial cells is called extrusion. When too many epithelial cells are present, the resulting overcrowding triggers this process to squeeze excess cells out of the layer and away from the organ. Usually, these cells quickly die. However, if the pathway that regulates this process—which involves a receptor protein called S1P2—is disturbed, the cells may instead be pushed into the space between the epithelial layer and the organ. When this happens, the cells are more likely to survive and may then form a tumor that invades the organ. Gu et al. interfered with extrusion by reducing the levels of the S1P2 receptor in layers of human epithelial cells grown in the laboratory. Fewer epithelial cells were squeezed out of these cell layers, making the layers up to three times as thick in places. Moreover, mutant zebrafish lacking the S1P2 receptor also accumulated epithelial masses throughout their bodies. Gu et al. found that disrupting the extrusion process made the cells resistant to chemotherapy, and that certain hard-to-treat human pancreatic, lung, and colon cancers had lower levels of the S1P2 receptors. Boosting the activity of S1P2 receptors helped to restore normal extrusion and reduced the size of pancreatic tumors in mice. Gu et al. then focused on an enzyme called Focal Adhesion Kinase that helps cells to survive. Treating zebrafish with a drug to block the activity of this enzyme left normal fish unharmed. However, in mutant fish with malfunctioning extrusion pathways, the drug rescued the number of cells that died, reduced the size and number of masses, and cured their leaky skin barrier. If further studies confirm the results, the drug may offer a new, less toxic, treatment for certain cancers that do not respond to currently available treatments. DOI:http://dx.doi.org/10.7554/eLife.04069.002
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Affiliation(s)
- Yapeng Gu
- Huntsman Cancer Institute, University of Utah, Salt Lake City, United States
| | - Jill Shea
- Department of Surgery, University of Utah, Salt Lake City, United States
| | - Gloria Slattum
- Huntsman Cancer Institute, University of Utah, Salt Lake City, United States
| | - Matthew A Firpo
- Department of Surgery, University of Utah, Salt Lake City, United States
| | - Margaret Alexander
- Huntsman Cancer Institute, University of Utah, Salt Lake City, United States
| | - Sean J Mulvihill
- Department of Surgery, University of Utah, Salt Lake City, United States
| | - Vita M Golubovskaya
- Department of Surgical Oncology, Roswell Park Cancer Institute, Buffalo, United States
| | - Jody Rosenblatt
- Huntsman Cancer Institute, University of Utah, Salt Lake City, United States
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