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Schultz CR, Sheldon RD, Xie H, Demireva EY, Uhl KL, Agnew DW, Geerts D, Bachmann AS. New K50R mutant mouse models reveal impaired hypusination of eif5a2 with alterations in cell metabolite landscape. Biol Open 2023; 12:290754. [PMID: 36848144 PMCID: PMC10084858 DOI: 10.1242/bio.059647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 02/21/2023] [Indexed: 03/01/2023] Open
Abstract
The eukaryotic translation initiation factor 5A1 (eIF5A1) and 5A2 (eIF5A2) are important proteins in a variety of physiological and pathophysiological processes and their function has been linked to neurodevelopmental disorders, cancer, and viral infections. Here, we report two new genome-edited mouse models, generated using a CRISPR-Cas9 approach, in which the amino acid residue lysine 50 is replaced with arginine 50 (K50R) in eIF5A1 or in the closely related eIF5A2 protein. This mutation prevents the spermidine-dependent post-translational formation of hypusine, a unique lysine derivative that is necessary for activation of eIF5A1 and eIF5A2. Mouse brain lysates from homozygous eif5a2-K50R mutant mice (eif5a2K50R/K50R) confirmed the absence of hypusine formation of eIF5A2, and metabolomic analysis of primary mouse dermal fibroblasts revealed significant alterations in the metabolite landscape compared to controls including increased levels of tryptophan, kyrunenine, pyridoxine, nicotinamide adenine dinucleotide, riboflavin, flavin adenine dinucleotide, pantothenate, and coenzyme A. Further supported by new publicly available bioinformatics data, these new mouse models represent excellent in vivo models to study hypusine-dependent biological processes, hypusination-related disorders caused by eIF5A1 and eIF5A2 gene aberrations or mRNA expression dysregulation, as well as several major human cancer types and potential therapies.
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Affiliation(s)
- Chad R Schultz
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA
| | - Ryan D Sheldon
- Core Technologies and Services, Mass Spectrometry Core, Van Andel Institute, Grand Rapids, MI 49503, USA
| | - Huirong Xie
- Transgenic and Genome Editing Facility, Institute for Quantitative Health Science and Engineering, Research Technology Support Facility, Michigan State University, East Lansing, MI 48824, USA
| | - Elena Y Demireva
- Transgenic and Genome Editing Facility, Institute for Quantitative Health Science and Engineering, Research Technology Support Facility, Michigan State University, East Lansing, MI 48824, USA
| | - Katie L Uhl
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA
| | - Dalen W Agnew
- Department of Pathobiology & Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA
| | - Dirk Geerts
- Department of Hematology, Amsterdam University Medical Center, Location VUMC, 1081 HV Amsterdam, The Netherlands
| | - André S Bachmann
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA
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Zhou XE, Schultz CR, Suino Powell K, Henrickson A, Lamp J, Brunzelle JS, Demeler B, Vega IE, Bachmann AS, Melcher K. Structure and Enzymatic Activity of an Intellectual Disability-Associated Ornithine Decarboxylase Variant, G84R. ACS Omega 2022; 7:34665-34675. [PMID: 36188294 PMCID: PMC9520691 DOI: 10.1021/acsomega.2c04702] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 08/30/2022] [Indexed: 06/13/2023]
Abstract
Ornithine decarboxylase (ODC) is a rate-limiting enzyme for the synthesis of polyamines (PAs). PAs are required for proliferation, and increased ODC activity is associated with cancer and neural over-proliferation. ODC levels and activity are therefore tightly regulated, including through the ODC-specific inhibitor, antizyme AZ1. Recently, ODC G84R has been reported as a partial loss-of-function variant that is associated with intellectual disability and seizures. However, G84 is distant from both the catalytic center and the ODC homodimerization interface. To understand how G84R modulates ODC activity, we have determined the crystal structure of ODC G84R in both the presence and the absence of the cofactor pyridoxal 5-phosphate. The structures show that the replacement of G84 by arginine leads to hydrogen bond formation of R84 with F420, the last residue of the ODC C-terminal helix, a structural element that is involved in the AZ1-mediated proteasomal degradation of ODC. In contrast, the catalytic center is essentially indistinguishable from that of wildtype ODC. We therefore reanalyzed the catalytic activity of ODC G84R and found that it is rescued when the protein is purified in the presence of a reducing agent to mimic the reducing environment of the cytoplasm. This suggests that R84 may exert its neurological effects not through reducing ODC catalytic activity but through misregulation of its AZ1-mediated proteasomal degradation.
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Affiliation(s)
- X. Edward Zhou
- Department
of Structural Biology, Van Andel Institute, Grand Rapids, Michigan 49503, United States
| | - Chad R. Schultz
- Department
of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, Michigan 49546, United States
| | - Kelly Suino Powell
- Department
of Structural Biology, Van Andel Institute, Grand Rapids, Michigan 49503, United States
| | - Amy Henrickson
- Department
of Chemistry and Biochemistry, The University
of Lethbridge, Lethbridge, AB T1K3M4, Canada
| | - Jared Lamp
- Department
of Translational Neuroscience, Integrated Mass Spectrometry Unit,
College of Human Medicine, Michigan State
University, Grand
Rapids, Michigan 49503, United States
| | - Joseph S. Brunzelle
- Northwestern
University Synchrotron Research Center, Life Sciences Collaborative
Access Team, Northwestern University, Argonne, Illinois 60439, United States
| | - Borries Demeler
- Department
of Chemistry and Biochemistry, The University
of Lethbridge, Lethbridge, AB T1K3M4, Canada
- Department
of Chemistry and Biochemistry, The University
of Montana, Missoula, Montana 59812, United
States
| | - Irving E. Vega
- Department
of Translational Neuroscience, Integrated Mass Spectrometry Unit,
College of Human Medicine, Michigan State
University, Grand
Rapids, Michigan 49503, United States
| | - André S. Bachmann
- Department
of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, Michigan 49546, United States
| | - Karsten Melcher
- Department
of Structural Biology, Van Andel Institute, Grand Rapids, Michigan 49503, United States
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Kim HI, Schultz CR, Chandramouli GVR, Geerts D, Risinger JI, Bachmann AS. Pharmacological targeting of polyamine and hypusine biosynthesis reduces tumor activity of endometrial cancer. J Drug Target 2022; 30:623-633. [PMID: 35100927 DOI: 10.1080/1061186x.2022.2036164] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Endometrial cancer (EC) is a common and deadly cancer in women and novel therapeutic approaches are urgently needed. Polyamines (putrescine, spermidine, spermine) are critical for mammalian cell proliferation and MYC coordinately regulates polyamine metabolism through ornithine decarboxylase (ODC). ODC is a MYC target gene and rate-limiting enzyme of polyamine biosynthesis and the FDA-approved anti-protozoan drug α-difluoromethylornithine (DFMO) inhibits ODC activity and induces polyamine depletion that leads to tumor growth arrest. Spermidine is required for the hypusine-dependent activation of eukaryotic translation initiation factors 5A1 (eIF5A1) and 5A2 (eIF5A2) and connects the MYC/ODC-induced deregulation of spermidine to eIF5A1/2 protein translation, which is increased during cancer cell proliferation. We show that the eIF5A1 is significantly upregulated in EC cells compared to control cells (p = 0.000038) and that combined pharmacological targeting of ODC and eIF5A hypusination with cytostatic drugs DFMO and N1-guanyl-1,7-diaminoheptane (GC7), respectively, reduces eIF5A1 activation and synergistically induces apoptosis in EC cells. In vivo, DFMO/GC7 suppressed xenografted EC tumor growth in mice more potently than each drug alone compared to control (p = 0.002) and decreased putrescine (p = 0.045) and spermidine levels in tumor tissues. Our data suggest DFMO and GC7 combination therapy may be useful in the treatment or prevention of EC.
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Affiliation(s)
- Hong Im Kim
- Department of Obstetrics, Gynecology and Reproductive Biology, College of Human Medicine, Michigan State University, Grand Rapids MI
| | - Chad R Schultz
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids MI
| | | | - Dirk Geerts
- Glycostem Therapeutics, Oss, The Netherlands
| | - John I Risinger
- Department of Obstetrics, Gynecology and Reproductive Biology, College of Human Medicine, Michigan State University, Grand Rapids MI
| | - André S Bachmann
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids MI
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Schultz CR, Swanson MA, Dowling TC, Bachmann AS. Probenecid increases renal retention and antitumor activity of DFMO in neuroblastoma. Cancer Chemother Pharmacol 2021; 88:607-617. [PMID: 34129075 DOI: 10.1007/s00280-021-04309-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 05/30/2021] [Indexed: 01/14/2023]
Abstract
BACKGROUND Neuroblastoma (NB) is the most common extracranial solid tumor in children. Interference with the polyamine biosynthesis pathway by inhibition of MYCN-activated ornithine decarboxylase (ODC) is a validated approach. The ODC inhibitor α-difluoromethylornithine (DFMO, or Eflornithine) has been FDA-approved for the treatment of trypanosomiasis and hirsutism and has advanced to clinical cancer trials including NB as well as cancer-unrelated human diseases. One key challenge of DFMO is its rapid renal clearance and the need for high and frequent drug dosing during treatment. METHODS We performed in vivo pharmacokinetic (PK), antitumorigenic, and molecular studies with DFMO/probenecid using NB patient-derived xenografts (PDX) in mice. We used LC-MS/MS, HPLC, and immunoblotting to analyze blood, brain tissue, and PDX tumor tissue samples collected from mice. RESULTS The organic anion transport 1/3 (OAT 1/3) inhibitor probenecid reduces the renal clearance of DFMO and significantly increases the antitumor activity of DFMO in PDX of NB (P < 0.02). Excised tumors revealed that DFMO/probenecid treatment decreases polyamines putrescine and spermidine, reduces MYCN protein levels and dephosphorylates retinoblastoma (Rb) protein (p-RbSer795), suggesting DFMO/probenecid-induced cell cycle arrest. CONCLUSION Addition of probenecid as an adjuvant to DFMO therapy may be suitable to decrease overall dose and improve drug efficacy in vivo.
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Affiliation(s)
- Chad R Schultz
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, 400 Monroe Ave, NW, Grand Rapids, MI, 49503, USA
| | - Matthew A Swanson
- Shimadzu Core Laboratory for Academic and Research Excellence, Ferris State University, Big Rapids, MI, USA
| | - Thomas C Dowling
- Department of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, MI, USA
| | - André S Bachmann
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, 400 Monroe Ave, NW, Grand Rapids, MI, 49503, USA.
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5
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Prokop JW, Bupp CP, Frisch A, Bilinovich SM, Campbell DB, Vogt D, Schultz CR, Uhl KL, VanSickle E, Rajasekaran S, Bachmann AS. Emerging Role of ODC1 in Neurodevelopmental Disorders and Brain Development. Genes (Basel) 2021; 12:genes12040470. [PMID: 33806076 PMCID: PMC8064465 DOI: 10.3390/genes12040470] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 03/15/2021] [Accepted: 03/22/2021] [Indexed: 01/18/2023] Open
Abstract
Ornithine decarboxylase 1 (ODC1 gene) has been linked through gain-of-function variants to a rare disease featuring developmental delay, alopecia, macrocephaly, and structural brain anomalies. ODC1 has been linked to additional diseases like cancer, with growing evidence for neurological contributions to schizophrenia, mood disorders, anxiety, epilepsy, learning, and suicidal behavior. The evidence of ODC1 connection to neural disorders highlights the need for a systematic analysis of ODC1 genotype-to-phenotype associations. An analysis of variants from ClinVar, Geno2MP, TOPMed, gnomAD, and COSMIC revealed an intellectual disability and seizure connected loss-of-function variant, ODC G84R (rs138359527, NC_000002.12:g.10444500C > T). The missense variant is found in ~1% of South Asian individuals and results in 2.5-fold decrease in enzyme function. Expression quantitative trait loci (eQTLs) reveal multiple functionally annotated, non-coding variants regulating ODC1 that associate with psychiatric/neurological phenotypes. Further dissection of RNA-Seq during fetal brain development and within cerebral organoids showed an association of ODC1 expression with cell proliferation of neural progenitor cells, suggesting gain-of-function variants with neural over-proliferation and loss-of-function variants with neural depletion. The linkage from the expression data of ODC1 in early neural progenitor proliferation to phenotypes of neurodevelopmental delay and to the connection of polyamine metabolites in brain function establish ODC1 as a bona fide neurodevelopmental disorder gene.
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Affiliation(s)
- Jeremy W. Prokop
- Department of Pediatrics and Human Development, Michigan State University, Grand Rapids, MI 49503, USA; (C.P.B.); (A.F.); (S.M.B.); (D.B.C.); (D.V.); (C.R.S.); (K.L.U.); (S.R.)
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824, USA
- Center for Research in Autism, Intellectual, and Other Neurodevelopmental Disabilities, Michigan State University, East Lansing, MI 48824, USA
- Correspondence: (J.W.P.); (A.S.B.)
| | - Caleb P. Bupp
- Department of Pediatrics and Human Development, Michigan State University, Grand Rapids, MI 49503, USA; (C.P.B.); (A.F.); (S.M.B.); (D.B.C.); (D.V.); (C.R.S.); (K.L.U.); (S.R.)
- Spectrum Health Medical Genetics, Grand Rapids, MI 49503, USA;
| | - Austin Frisch
- Department of Pediatrics and Human Development, Michigan State University, Grand Rapids, MI 49503, USA; (C.P.B.); (A.F.); (S.M.B.); (D.B.C.); (D.V.); (C.R.S.); (K.L.U.); (S.R.)
| | - Stephanie M. Bilinovich
- Department of Pediatrics and Human Development, Michigan State University, Grand Rapids, MI 49503, USA; (C.P.B.); (A.F.); (S.M.B.); (D.B.C.); (D.V.); (C.R.S.); (K.L.U.); (S.R.)
| | - Daniel B. Campbell
- Department of Pediatrics and Human Development, Michigan State University, Grand Rapids, MI 49503, USA; (C.P.B.); (A.F.); (S.M.B.); (D.B.C.); (D.V.); (C.R.S.); (K.L.U.); (S.R.)
- Center for Research in Autism, Intellectual, and Other Neurodevelopmental Disabilities, Michigan State University, East Lansing, MI 48824, USA
- Neuroscience Program, Michigan State University, East Lansing, MI 48824, USA
| | - Daniel Vogt
- Department of Pediatrics and Human Development, Michigan State University, Grand Rapids, MI 49503, USA; (C.P.B.); (A.F.); (S.M.B.); (D.B.C.); (D.V.); (C.R.S.); (K.L.U.); (S.R.)
- Center for Research in Autism, Intellectual, and Other Neurodevelopmental Disabilities, Michigan State University, East Lansing, MI 48824, USA
- Neuroscience Program, Michigan State University, East Lansing, MI 48824, USA
| | - Chad R. Schultz
- Department of Pediatrics and Human Development, Michigan State University, Grand Rapids, MI 49503, USA; (C.P.B.); (A.F.); (S.M.B.); (D.B.C.); (D.V.); (C.R.S.); (K.L.U.); (S.R.)
| | - Katie L. Uhl
- Department of Pediatrics and Human Development, Michigan State University, Grand Rapids, MI 49503, USA; (C.P.B.); (A.F.); (S.M.B.); (D.B.C.); (D.V.); (C.R.S.); (K.L.U.); (S.R.)
| | | | - Surender Rajasekaran
- Department of Pediatrics and Human Development, Michigan State University, Grand Rapids, MI 49503, USA; (C.P.B.); (A.F.); (S.M.B.); (D.B.C.); (D.V.); (C.R.S.); (K.L.U.); (S.R.)
- Pediatric Intensive Care Unit, Helen DeVos Children’s Hospital, Grand Rapids, MI 49503, USA
- Office of Research, Spectrum Health, Grand Rapids, MI 49503, USA
| | - André S. Bachmann
- Department of Pediatrics and Human Development, Michigan State University, Grand Rapids, MI 49503, USA; (C.P.B.); (A.F.); (S.M.B.); (D.B.C.); (D.V.); (C.R.S.); (K.L.U.); (S.R.)
- Correspondence: (J.W.P.); (A.S.B.)
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Abstract
The natural product allicin is a reactive sulfur species (RSS) from garlic (Allium sativum L.). Neuroblastoma (NB) is an early childhood cancer arising from the developing peripheral nervous system. Ornithine decarboxylase (ODC) is a rate-limiting enzyme in the biosynthesis of polyamines, which are oncometabolites that contribute to cell proliferation in NB and other c-MYC/MYCN-driven cancers. Both c-MYC and MYCN directly transactivate the E-box gene ODC1, a validated anticancer drug target. We identified allicin as a potent ODC inhibitor in a specific radioactive in vitro assay using purified human ODC. Allicin was ∼23 000-fold more potent (IC50 = 11 nM) than DFMO (IC50 = 252 μM), under identical in vitro assay conditions. ODC is a homodimer with 12 cysteines per monomer, and allicin reversibly S-thioallylates cysteines. In actively proliferating human NB cells allicin inhibited ODC enzyme activity, reduced cellular polyamine levels, inhibited cell proliferation (IC50 9-19 μM), and induced apoptosis. The natural product allicin is a new ODC inhibitor and could be developed for use in conjunction with other anticancer treatments, the latter perhaps at a lower than usual dosage, to achieve drug synergism with good prognosis and reduced adverse effects.
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Affiliation(s)
- Chad R. Schultz
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI, USA
| | - Martin C.H. Gruhlke
- Department of Plant Physiology, RWTH Aachen University, 52056 Aachen, Germany
| | - Alan J. Slusarenko
- Department of Plant Physiology, RWTH Aachen University, 52056 Aachen, Germany
- Corresponding Authors: André S. Bachmann, Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, 400 Monroe Ave, NW, Grand Rapids, MI 49503, USA. Tel: +616-234-2841, or Alan J. Slusarenko, Department of Plant Physiology, RWTH Aachen University, Worringerweg 1, D-52074 Aachen, Germany. Tel: +49-241-80-266-50,
| | - André S. Bachmann
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI, USA
- Corresponding Authors: André S. Bachmann, Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, 400 Monroe Ave, NW, Grand Rapids, MI 49503, USA. Tel: +616-234-2841, or Alan J. Slusarenko, Department of Plant Physiology, RWTH Aachen University, Worringerweg 1, D-52074 Aachen, Germany. Tel: +49-241-80-266-50,
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Schultz CR, Gruhlke MC, Slusarenko AJ, Bachmann AS. Abstract 464: Allicin, a potent new ornithine decarboxylase inhibitor in neuroblastoma. Cancer Res 2020. [DOI: 10.1158/1538-7445.am2020-464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The purpose of this study was to test if allicin inhibits ornithine decarboxylase (ODC) in pediatric neuroblastoma (NB). The natural product allicin is a reactive sulfur species (RSS) from garlic (Allium sativum L.). NB is an early childhood cancer arising from the developing peripheral nervous system. In up to 25% of cases MYCN gene amplification is correlated to high tumor stage and poor patient prognosis. High stage NB relapses frequently despite multimodal therapy and relapsed tumors are virtually untreatable. Therefore, there is a clear need for specific, novel therapeutics. MYCN transactivates the E-box gene ODC1, and the gene product ODC is a rate-limiting enzyme in polyamine biosynthesis. The increase of polyamines (putrescine, spermidine, spermine) triggers cell hyperproliferation in NB and other MYC-driven cancers through the activation of Rb-regulated cell cycle progression. ODC is a validated drug target and α-difluoromethylornithine (DFMO) is an ODC inhibitor under investigation in phase II NB trials. Although a safe drug with clinical promise, DFMO has various challenges including the need for exceptionally high treatment doses and rapid renal clearance in the urine. In an effort to identify pharmacologically superior ODC inhibitors, we identified allicin as a potent ODC inhibitor using a specific radioactive in vitro activity assay with purified ODC. Allicin also inhibited ODC activity in actively growing NB cells, reduced polyamine levels, and induced apoptosis in cell cultures. ODC is a homodimer with 12 cysteines per monomer and allicin S-thioallylates cysteines. Allicin reacts with, and is titrated-out by, low molecular weight thiols like dithiothreitol (DTT). Removal of DTT from the ODC activity assay reaction resulted in significantly higher allicin potency (IC50 at 11 nM). Although allicin has multiple cellular targets, our data reveal that one mode of action is ODC inhibition, which suppresses polyamine accumulation and induces apoptosis. The natural product allicin could be used in conjunction with other anticancer treatments, the latter at a lower than usual dosage, to achieve drug synergism with good prognosis and less side-effects.
Citation Format: Chad R. Schultz, Martin C. Gruhlke, Alan J. Slusarenko, Andre S. Bachmann. Allicin, a potent new ornithine decarboxylase inhibitor in neuroblastoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 464.
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8
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Bupp CP, Schultz CR, Uhl KL, Rajasekaran S, Bachmann AS. Cover Image, Volume 176A, Number 12, December 2018. Am J Med Genet A 2018. [DOI: 10.1002/ajmg.a.61036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Caleb P. Bupp
- Medical Genetics, Spectrum Health and Helen DeVos Children's Hospital; Grand Rapids Michigan
- Department of Pediatrics and Human Development; College of Human Medicine, Michigan State University; Grand Rapids Michigan
| | - Chad R. Schultz
- Department of Pediatrics and Human Development; College of Human Medicine, Michigan State University; Grand Rapids Michigan
| | - Katie L. Uhl
- Department of Pediatrics and Human Development; College of Human Medicine, Michigan State University; Grand Rapids Michigan
| | - Surender Rajasekaran
- Department of Pediatrics and Human Development; College of Human Medicine, Michigan State University; Grand Rapids Michigan
- Pediatric Critical Care Medicine; Helen DeVos Children's Hospital; Grand Rapids Michigan
| | - André S. Bachmann
- Department of Pediatrics and Human Development; College of Human Medicine, Michigan State University; Grand Rapids Michigan
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9
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Bupp CP, Schultz CR, Uhl KL, Rajasekaran S, Bachmann AS. Novel de novo pathogenic variant in the ODC1 gene in a girl with developmental delay, alopecia, and dysmorphic features. Am J Med Genet A 2018; 176:2548-2553. [PMID: 30239107 DOI: 10.1002/ajmg.a.40523] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 08/03/2018] [Accepted: 08/04/2018] [Indexed: 11/09/2022]
Abstract
The ornithine decarboxylase 1 (ODC1) gene plays an important role in physiological and cell developmental processes including embryogenesis, organogenesis, and neoplastic cell growth. Here, we report an 32-month-old Caucasian female with a heterozygous de novo nonsense mutation in the ODC1 gene that leads to a premature abrogation of 14-aa residues at the ODC protein c-terminus. This is the first human case confirming similar symptoms observed in a transgenic ODC1 mouse model first described over 20 years ago. Phenotypic manifestations include macrosomia, macrocephaly, developmental delay, alopecia, spasticity, hypotonia, cutaneous vascular malformation, delayed visual maturation, and sensorineural hearing loss. We here describe for the first time a new pediatric disorder that is directly linked to a de novo pathogenic variant in the ODC1 gene. The ODC1 gene mutation (c.1342 A>T) was identified by whole-exome sequencing and confirmed by Sanger sequencing. Red blood cells obtained from our patient showed elevated ODC protein and polyamine levels compared to healthy controls. Our autosomal dominant patient who carries this gain-of-function ODC1 mutation may benefit from treatment with α-difluoromethylornithine, a well-tolerated, U.S. Food and Drug Administration (FDA). FDA-approved drug.
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Affiliation(s)
- Caleb P Bupp
- Medical Genetics, Spectrum Health and Helen DeVos Children's Hospital, Grand Rapids, Michigan.,Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, Michigan
| | - Chad R Schultz
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, Michigan
| | - Katie L Uhl
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, Michigan
| | - Surender Rajasekaran
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, Michigan.,Pediatric Critical Care Medicine, Helen DeVos Children's Hospital, Grand Rapids, Michigan
| | - André S Bachmann
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, Michigan
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10
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Weicht RR, Schultz CR, Geerts D, Uhl KL, Bachmann AS. Polyamine Biosynthetic Pathway as a Drug Target for Osteosarcoma Therapy. Med Sci (Basel) 2018; 6:E65. [PMID: 30115881 PMCID: PMC6165283 DOI: 10.3390/medsci6030065] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 08/09/2018] [Accepted: 08/13/2018] [Indexed: 12/13/2022] Open
Abstract
Osteosarcoma (OS) is the most common bone tumor in children. Polyamines (PAs) are ubiquitous cations involved in many cell processes including tumor development, invasion and metastasis. In other pediatric cancer models, inhibition of the PA biosynthesis pathway with ornithine decarboxylase (ODC) inhibitor alpha-difluoromethylornithine (DFMO) results in decreased cell proliferation and differentiation. In OS, the PA pathway has not been evaluated. DFMO is an attractive, orally administered drug, is well tolerated, can be given for prolonged periods, and is already used in pediatric patients. Three OS cell lines were used to study the cellular effects of PA inhibition with DFMO: MG-63, U-2 OS and Saos-2. Effects on proliferation were analyzed by cell count, flow cytometry-based cell cycle analysis and RealTime-Glo™ MT Cell Viability assays. Intracellular PA levels were measured with high-performance liquid chromatography (HPLC). Western blot analysis was used to evaluate cell differentiation. DFMO exposure resulted in significantly decreased cell proliferation in all cell lines. After treatment, intracellular spermidine levels were drastically decreased. Cell cycle arrest at G₂/M was observed in U-2 OS and Saos-2. Cell differentiation was most prominent in MG-63 and U-2 OS as determined by increases in the terminal differentiation markers osteopontin and collagen 1a1. Cell proliferation continued to be suppressed for several days after removal of DFMO. Based on our findings, DFMO is a promising new adjunct to current osteosarcoma therapy in patients at high risk of relapse, such as those with poor necrosis at resection or those with metastatic or recurrent osteosarcoma. It is a well-tolerated oral drug that is currently in phase II clinical trials in pediatric neuroblastoma patients as a maintenance therapy. The same type of regimen may also improve outcomes in osteosarcoma patients in whom there have been essentially no medical advances in the last 30 years.
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Affiliation(s)
- Rebecca R. Weicht
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, 400 Monroe Avenue, NW, Grand Rapids, MI 49503, USA; (R.R.W.); (C.R.S.); (K.L.U.)
- Helen DeVos Children’s Hospital, Department of Pediatric Hematology Oncology, Grand Rapids, MI 49503, USA
| | - Chad R. Schultz
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, 400 Monroe Avenue, NW, Grand Rapids, MI 49503, USA; (R.R.W.); (C.R.S.); (K.L.U.)
| | - Dirk Geerts
- Department of Medical Biology, Amsterdam University Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands;
| | - Katie L. Uhl
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, 400 Monroe Avenue, NW, Grand Rapids, MI 49503, USA; (R.R.W.); (C.R.S.); (K.L.U.)
| | - André S. Bachmann
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, 400 Monroe Avenue, NW, Grand Rapids, MI 49503, USA; (R.R.W.); (C.R.S.); (K.L.U.)
- Helen DeVos Children’s Hospital, Department of Pediatric Hematology Oncology, Grand Rapids, MI 49503, USA
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Uhl KL, Schultz CR, Geerts D, Bachmann AS. Abstract 1902: Potential role of DYRK family kinases in harmine-induced apoptosis in neuroblastoma. Cancer Res 2018. [DOI: 10.1158/1538-7445.am2018-1902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The purpose of this study was to determine the effect of the natural product Harmine in human neuroblastoma (NB). NB is an early childhood malignancy arising from the developing peripheral nervous system. In up to 25% of cases MYCN gene amplification is correlated to high tumor stage and poor patient prognosis. High stage NB relapses frequently in spite of multimodal therapy and is then virtually untreatable. There is a clear need for specific, novel therapeutics. Harmine is a tricyclic β-carboline alkaloid from the harmal plant with cytostatic and cytotoxic effects on tumor cells. It is capable of blocking the activity of mitogen activate protein kinase (MAPK) and the dual specificity tyrosine-phosphorylation-regulated kinase (DYRK) family proteins. These kinases inhibit apoptosis and encourage proliferation. Four human NB cell lines were used to study the effects of Harmine treatment: SK-N-BE(2)-C and KELLY (MYCN amplified) as well as SK-N-AS and SK-N-FI (MYCN single copy). Molecular interaction models of Harmine bound to DYRK family kinases were generated by computational docking using x-ray structures. The anti-cancer properties of Harmine were analyzed by real-time cell viability assays, in a dose-dependent manner, over a 72 hour period. The IC50 values were 169.9, 170.8, and 791.7 μM for SK-N-BE(2)-C, KELLY, and SK-N-FI, respectively, after 72 hours. Apoptosis assays for caspase activation, PARP cleavage, and annexin V induction, were performed using Western blot and flow cytometry. NB cell line exposure to 100 μM Harmine resulted in caspase-3/7 and caspase 9 activation, PARP cleavage, and annexin V-positive stained cells as early as 24 hours after treatment, indicating apoptosis induction. These results led us to investigate the clinical correlations of DYRK family gene expression in NB tumors. The patient results support our hypothesis that Harmine induces NB cell death through a cellular mechanism that involves DYRK family kinases and triggers caspase-mediated apoptosis.
Citation Format: Katie L. Uhl, Chad R. Schultz, Dirk Geerts, Andre S. Bachmann. Potential role of DYRK family kinases in harmine-induced apoptosis in neuroblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1902.
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Affiliation(s)
| | | | - Dirk Geerts
- 2University of Amsterdam, Amsterdam, Netherlands
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Uhl KL, Schultz CR, Geerts D, Bachmann AS. Harmine, a dual-specificity tyrosine phosphorylation-regulated kinase (DYRK) inhibitor induces caspase-mediated apoptosis in neuroblastoma. Cancer Cell Int 2018; 18:82. [PMID: 29977157 PMCID: PMC5992763 DOI: 10.1186/s12935-018-0574-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 05/26/2018] [Indexed: 11/12/2022] Open
Abstract
Background Neuroblastoma (NB) is an early childhood malignancy that arises from the developing sympathetic nervous system. Harmine is a tricyclic β-carboline alkaloid isolated from the harmal plant that exhibits both cytostatic and cytotoxic effects. Harmine is capable of blocking the activities of dual-specificity tyrosine phosphorylation-regulated kinase (DYRK) family proteins and mitogen-activated protein kinase. These kinases promote proliferation and inhibit apoptosis. Methods Four human NB cell lines were used to study the effects of harmine treatment: SKNBE and KELLY (MYCN-amplified) as well as SKNAS and SKNFI (MYCN non-amplified). The anti-cancer properties of harmine were examined by RealTime-Glo MT cell viability assays, caspase activity assays, PARP cleavage using Western blot analysis, and flow cytometry-based Annexin V detection. A molecular interaction model of harmine bound to the DYRK2 family kinase was generated by computational docking using X-ray structures. NB tumors from human patients were profiled for DYRK mRNA expression patterns and clinical correlations using the R2 platform. Results The IC50 values for harmine after 72 h treatment were 169.6, 170.8, and 791.7 μM for SKNBE, KELLY, and SKNFI, respectively. Exposure of these NB cell lines to 100 μM of harmine resulted in caspase-3/7 and caspase-9 activation as well as caspase-mediated PARP cleavage and Annexin V-positive stained cells, as early as 24 h after treatment, clearly suggesting apoptosis induction, especially in MYCN-amplified cell lines. Elevated DYRK2 mRNA levels correlated with poor prognosis in a large cohort of NB tumors. Conclusion Harmine is a known inhibitor of DYRK family kinases. It can induce apoptosis in NB cell lines, which led us to investigate the clinical correlations of DYRK family gene expression in NB tumors. The patient results support our hypothesis that DYRK inhibition by harmine and the subsequent triggering of caspase-mediated apoptosis might present a novel approach to NB therapy. Electronic supplementary material The online version of this article (10.1186/s12935-018-0574-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Katie L Uhl
- 1Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, 400 Monroe Avenue NW, Grand Rapids, MI 49503 USA
| | - Chad R Schultz
- 1Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, 400 Monroe Avenue NW, Grand Rapids, MI 49503 USA
| | - Dirk Geerts
- 2Department of Medical Biology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - André S Bachmann
- 1Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, 400 Monroe Avenue NW, Grand Rapids, MI 49503 USA
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Schultz CR, Geerts D, Mooney M, El-Khawaja R, Koster J, Bachmann AS. Synergistic drug combination GC7/DFMO suppresses hypusine/spermidine-dependent eIF5A activation and induces apoptotic cell death in neuroblastoma. Biochem J 2018; 475:531-545. [PMID: 29295892 DOI: 10.1042/bcj20170597] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 12/19/2017] [Accepted: 01/01/2018] [Indexed: 12/17/2023]
Abstract
The eukaryotic initiation factor 5A (eIF5A), which contributes to several crucial processes during protein translation, is the only protein that requires activation by a unique post-translational hypusine modification. eIF5A hypusination controls cell proliferation and has been linked to cancer. eIF5A hypusination requires the enzymes deoxyhypusine synthase (DHPS) and deoxyhypusine hydroxylase and uniquely depends on the polyamine (PA) spermidine as the sole substrate. Ornithine decarboxylase (ODC) is the rate-limiting enzyme in PA biosynthesis. Both ODC and PAs control cell proliferation and are frequently dysregulated in cancer. Since only spermidine can activate eIF5A, we chose the hypusine-PA nexus as a rational target to identify new drug combinations with synergistic antiproliferative effects. We show that elevated mRNA levels of the two target enzymes DHPS and ODC correlate with poor prognosis in a large cohort of neuroblastoma (NB) tumors. The DHPS inhibitor GC7 (N1-guanyl-1,7-diaminoheptane) and the ODC inhibitor α-difluoromethylornithine (DFMO) are target-specific and in combination induced synergistic effects in NB at concentrations that were not individually cytotoxic. Strikingly, while each drug alone at higher concentrations is known to induce p21/Rb- or p27/Rb-mediated G1 cell cycle arrest, we found that the drug combination induced caspase 3/7/9, but not caspase 8-mediated apoptosis, in NB cells. Hypusinated eIF5A levels and intracellular spermidine levels correlated directly with drug treatments, signifying specific drug targeting effects. This two-pronged GC7/DFMO combination approach specifically inhibits both spermidine biosynthesis and post-translational, spermidine-dependent hypusine-eIF5A activation, offering an exciting clue for improved NB drug therapy.
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Affiliation(s)
- Chad R Schultz
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, U.S.A
| | - Dirk Geerts
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Marie Mooney
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, U.S.A
| | | | - Jan Koster
- Department of Oncogenomics, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - André S Bachmann
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, U.S.A.
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Kim HI, Schultz CR, Buras AL, Friedman E, Fedorko A, Seamon L, Chandramouli GVR, Maxwell GL, Bachmann AS, Risinger JI. Ornithine decarboxylase as a therapeutic target for endometrial cancer. PLoS One 2017; 12:e0189044. [PMID: 29240775 PMCID: PMC5730160 DOI: 10.1371/journal.pone.0189044] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 11/19/2017] [Indexed: 12/13/2022] Open
Abstract
Ornithine Decarboxylase (ODC) a key enzyme in polyamine biosynthesis is often overexpressed in cancers and contributes to polyamine-induced cell proliferation. We noted ubiquitous expression of ODC1 in our published endometrial cancer gene array data and confirmed this in the cancer genome atlas (TCGA) with highest expression in non-endometrioid, high grade, and copy number high cancers, which have the worst clinical outcomes. ODC1 expression was associated with worse overall survival and increased recurrence in three endometrial cancer gene expression datasets. Importantly, we confirmed these findings using quantitative real-time polymerase chain reaction (qRT-PCR) in a validation cohort of 60 endometrial cancers and found that endometrial cancers with elevated ODC1 had significantly shorter recurrence-free intervals (KM log-rank p = 0.0312, Wald test p = 5.59e-05). Difluoromethylornithine (DFMO) a specific inhibitor of ODC significantly reduced cell proliferation, cell viability, and colony formation in cell line models derived from undifferentiated, endometrioid, serous, carcinosarcoma (mixed mesodermal tumor; MMT) and clear cell endometrial cancers. DFMO also significantly reduced human endometrial cancer ACI-98 tumor burden in mice compared to controls (p = 0.0023). ODC-regulated polyamines (putrescine [Put] and/or spermidine [Spd]) known activators of cell proliferation were strongly decreased in response to DFMO, in both tumor tissue ([Put] (p = 0.0006), [Spd] (p<0.0001)) and blood plasma ([Put] (p<0.0001), [Spd] (p = 0.0049)) of treated mice. Our study indicates that some endometrial cancers appear particularly sensitive to DFMO and that the polyamine pathway in endometrial cancers in general and specifically those most likely to suffer adverse clinical outcomes could be targeted for effective treatment, chemoprevention or chemoprevention of recurrence.
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Affiliation(s)
- Hong Im Kim
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, Grand Rapids, Michigan, United States of America
| | - Chad R. Schultz
- Department of Pediatrics and Human Development, Michigan State University, Grand Rapids, Michigan, United States of America
| | - Andrea L. Buras
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, Grand Rapids, Michigan, United States of America
- Spectrum Health, Grand Rapids, Michigan, United States of America
| | | | - Alyssa Fedorko
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, Grand Rapids, Michigan, United States of America
- Spectrum Health, Grand Rapids, Michigan, United States of America
| | - Leigh Seamon
- Spectrum Health, Grand Rapids, Michigan, United States of America
| | | | - G. Larry Maxwell
- Department of Obsteterics and Gynecology, Inova Fairfax Women’s Hospital, Falls Church, Virginia, United States of America
| | - André S. Bachmann
- Department of Pediatrics and Human Development, Michigan State University, Grand Rapids, Michigan, United States of America
- * E-mail: (JR); (AB)
| | - John I. Risinger
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, Grand Rapids, Michigan, United States of America
- Spectrum Health, Grand Rapids, Michigan, United States of America
- * E-mail: (JR); (AB)
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Bakas NA, Schultz CR, Yco LP, Roberts CC, Chang CEA, Bachmann AS, Pirrung MC. Immunoproteasome inhibition and bioactivity of thiasyrbactins. Bioorg Med Chem 2017; 26:401-412. [PMID: 29269255 DOI: 10.1016/j.bmc.2017.11.048] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 11/21/2017] [Accepted: 11/29/2017] [Indexed: 12/12/2022]
Abstract
A family of macrodilactam natural products, the syrbactins, are known proteasome inhibitors. A small group of syrbactin analogs was prepared with a sulfur-for-carbon substitution to enhance synthetic accessibility and facilitate modulation of their solubility. Two of these compounds surprisingly proved to be inhibitors of the trypsin-like catalytic site, including of the immunoproteasome. Their bound and free conformations suggest special properties of the thiasyrbactin ring are responsible for this unusual preference, which may be exploited to develop drug-like immunoproteasome inhibitors. These compounds show greater selectivity than earlier compounds used to infer phenotypes of immunoproteasome inhibition, like ONX-0914.
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Affiliation(s)
- Nicole A Bakas
- Department of Chemistry, University of California, Riverside, CA 92521, USA
| | - Chad R Schultz
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA
| | - Lisette P Yco
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA
| | | | - Chia-En A Chang
- Department of Chemistry, University of California, Riverside, CA 92521, USA
| | - André S Bachmann
- Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA.
| | - Michael C Pirrung
- Department of Chemistry, University of California, Riverside, CA 92521, USA; Department of Pharmaceutical Sciences, University of California, Irvine, CA 92697, USA.
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16
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Kim HI, Schultz CR, Buras AL, Friedman E, Fedorko AM, Seamon LG, Chandramouli G, Bachmann AS, Risinger JI. Abstract 1242: Ornithine decarboxylase as a therapeutic target in endometrial cancer. Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-1242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Endometrial cancer is the 4th most common cancer and the 6th deadliest cancer in US women. The American Cancer Society estimates there will be 60,050 new endometrial cancers in 2016, an increase of more than 10% from the previous year highlighting the need for more effective treatments and prevention. Ornithine Decarboxylase (ODC) a key enzyme in polyamine synthesis is often overexpressed in cancers and contributes to cell proliferation and tumor growth. Therefore, ODC and the polyamine pathway are considered rational targets for cancer treatment or prevention. We noted ubiquitous expression of ODC1 in our previously published endometrial cancer gene array data and confirmed this in the cancer genome atlas (TCGA), finding expression in all four molecular sub-types with highest expression in copy number high cancers which have the worst clinical outcomes. Therefore, we explored the association of ODC1 gene expression with clinical outcomes of overall survival (OS) and recurrence in the TCGA cohort and noted that elevated ODC1 was significantly related to OS (Wald test p=0.001) and recurrence (p=0.01). Importantly, we confirmed these observations using QRT-PCR in a validation cohort of 60 endometrial cancers and found that endometrial cancers with elevated ODC1 had significantly shorter recurrence-free intervals (p=5.59x10-5) and elevated hazard ratio=3.72. Similar to TCGA data we also noted a strong trend to worse OS ( p=0.00014) with elevated hazard ratio 3.81. Numerous studies including clinical trials have examined the chemopreventive and anti-tumor effects of difluoromethylornithine (DFMO), a specific inhibitor of ODC. We found that DFMO treatment significantly reduced cell proliferation, cell viability, and colony formation in human cell line models derived from undifferentiated, endometrioid, serous, MMT and clear cell endometrial cancers. In contrast, immortalized uterine endometrial epithelial cells (EM E6/E7 TERT1) were less sensitive to DFMO. To confirm the significant effects of DFMO in vitro we performed an in vivo study with human endometrial cancer (ACI-98) tumor-bearing athymic nude mice. Xenografted mice were either treated with 2% (w/v) DFMO supplied in drinking water or water only (n=10/group). DFMO significantly reduced the tumor burden in mice compared to controls (p=0.0023). ODC-regulated polyamines (putrescine [Put] and spermidine [Spd]) known activators of cell proliferation were strongly decreased in response to DFMO, in both tumor tissue ([Put] (p=0.0006), [Spd] (p<0.0001)) and blood plasma ([Put] (p<0.0001), [Spd] (p=0.0049)) of treated mice. Results of these studies indicate that some endometrial cancers appear particularly sensitive to DFMO. Our findings indicate that the polyamine pathway in endometrial cancers in general and specifically those most clinically relevant endometrial cancers could be targeted for effective treatment, chemoprevention or chemoprevention of recurrence.
Citation Format: Hong Im Kim, Chad R. Schultz, Andrea L. Buras, Elizabeth Friedman, Alyssa M. Fedorko, Leigh G. Seamon, Gadisetti Chandramouli, André S. Bachmann, John I. Risinger. Ornithine decarboxylase as a therapeutic target in endometrial cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1242. doi:10.1158/1538-7445.AM2017-1242
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Affiliation(s)
- Hong Im Kim
- 1Michigan State University, Grand Rapids, MI
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17
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Thomas SL, Schultz CR, Mouzon E, Golembieski WA, Lemke N, Poisson LM, Gutierrez JA, Cottingham S, Rempel SA. Abstract 2363: Loss of Sparc in p53-null astrocytes alters collagen deposition and promotes macrophage activation and tumor phagocytosis. Cancer Res 2015. [DOI: 10.1158/1538-7445.am2015-2363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Both the induction of SPARC expression and the loss of the p53 tumor suppressor gene are changes that occur early in glioma development. Therefore, the upregulation of SPARC may cooperate with the loss of p53 to enhance cell survival and inhibit apoptosis during glioma formation. This study determined whether the loss of Sparc in astrocytes that are null for p53 (p53-null/Sparc-null) would result in reduced cell survival and tumor formation and increased tumor immunogenicity in an in vivo xenograft brain tumor model. In vitro, the loss of Sparc in p53-null astrocytes resulted in an increase in cell proliferation (15-33%, p<0.01); however, there was an inhibition of growth in soft agar. Intracranial xenografts of p53-null/Sparc-wt and p53-null/Sparc-null astrocytes were assessed for tumor size, proliferation rate, and SPARC expression. At 7 days post-implantation, Sparc-null astrocytes produced significantly smaller tumors (Wilcoxon rank-sum test p = 0.0091, median = 0.709mm2 for Sparc-wt and 0.240mm2 for Sparc-null) with a significantly lower MIB-1 proliferation index (Wilcoxon rank-sum test p = 0.0345, median = 8.6% for Sparc-wt and 0.4% for Sparc-null). By CD68 and periodic acid Schiff +/- diastase staining of xenograft tumors, it was found that Sparc-null tumors had a massive infiltration of microglia/macrophages with a phagocytic appearance compared to the activated, but non-phagocytic, microglia/macrophages present within the Sparc-wt tumors. The loss of Sparc in astrocytes and the resulting increase in microglia/macrophage activation lead to an alteration in the tumor microenvironment with increased collagen deposition and altered collagen structure at both 7 and 50 days post-implantation as assessed by picrosirius red and polarized light microscopy. Sparc-null tumors had increased collagen deposition with a long fiber structure compared to the small bundles of collagen present in Sparc-wt tumors. Our results indicate that the loss of p53 by deletion/mutation in the early stages of glioma formation may cooperate with the induction of SPARC to potentiate cancer cell survival and escape from immune surveillance.
Citation Format: Stacey L. Thomas, Chad R. Schultz, Ezekiell Mouzon, William A. Golembieski, Nancy Lemke, Laila M. Poisson, Jorge A. Gutierrez, Sandra Cottingham, Sandra A. Rempel. Loss of Sparc in p53-null astrocytes alters collagen deposition and promotes macrophage activation and tumor phagocytosis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2363. doi:10.1158/1538-7445.AM2015-2363
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Thomas SL, Schultz CR, Mouzon E, Golembieski WA, El Naili R, Radakrishnan A, Lemke N, Poisson LM, Gutiérrez JA, Cottingham S, Rempel SA. Loss of Sparc in p53-null Astrocytes Promotes Macrophage Activation and Phagocytosis Resulting in Decreased Tumor Size and Tumor Cell Survival. Brain Pathol 2015; 25:391-400. [PMID: 24862407 PMCID: PMC4520390 DOI: 10.1111/bpa.12161] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 05/19/2014] [Indexed: 12/26/2022] Open
Abstract
Both the induction of SPARC expression and the loss of the p53 tumor suppressor gene are changes that occur early in glioma development. Both SPARC and p53 regulate glioma cell survival by inverse effects on apoptotic signaling. Therefore, during glioma formation, the upregulation of SPARC may cooperate with the loss of p53 to enhance cell survival. This study determined whether the loss of Sparc in astrocytes that are null for p53 would result in reduced cell survival and tumor formation and increased tumor immunogenicity in an in vivo xenograft brain tumor model. In vitro, the loss of Sparc in p53‐null astrocytes resulted in an increase in cell proliferation, but a loss of tumorigenicity. At 7 days after intracranial implantation, Sparc‐null tumors had decreased tumor cell survival, proliferation and reduced tumor size. The loss of Sparc promoted microglia/macrophage activation and phagocytosis of tumor cells. Our results indicate that the loss of p53 by deletion/mutation in the early stages of glioma formation may cooperate with the induction of SPARC to potentiate cancer cell survival and escape from immune surveillance.
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Affiliation(s)
- Stacey L Thomas
- Department of Neurosurgery, Barbara Jane Levy Laboratory of Molecular Neuro-Oncology and Hermelin Brain Tumor Center, Henry Ford Hospital, Detroit, MI.,Department of Clinical Neurosciences, Laboratory of Molecular Neuro-Oncology, Division of Neurosurgery, Spectrum Health System, Grand Rapids, MI
| | - Chad R Schultz
- Department of Neurosurgery, Barbara Jane Levy Laboratory of Molecular Neuro-Oncology and Hermelin Brain Tumor Center, Henry Ford Hospital, Detroit, MI.,Department of Clinical Neurosciences, Laboratory of Molecular Neuro-Oncology, Division of Neurosurgery, Spectrum Health System, Grand Rapids, MI
| | - Ezekiell Mouzon
- Department of Neurosurgery, Barbara Jane Levy Laboratory of Molecular Neuro-Oncology and Hermelin Brain Tumor Center, Henry Ford Hospital, Detroit, MI
| | - William A Golembieski
- Department of Neurosurgery, Barbara Jane Levy Laboratory of Molecular Neuro-Oncology and Hermelin Brain Tumor Center, Henry Ford Hospital, Detroit, MI.,Department of Clinical Neurosciences, Laboratory of Molecular Neuro-Oncology, Division of Neurosurgery, Spectrum Health System, Grand Rapids, MI
| | - Reima El Naili
- Department of Neurosurgery, Barbara Jane Levy Laboratory of Molecular Neuro-Oncology and Hermelin Brain Tumor Center, Henry Ford Hospital, Detroit, MI
| | - Archanna Radakrishnan
- Department of Neurosurgery, Barbara Jane Levy Laboratory of Molecular Neuro-Oncology and Hermelin Brain Tumor Center, Henry Ford Hospital, Detroit, MI
| | - Nancy Lemke
- Department of Neurosurgery, Barbara Jane Levy Laboratory of Molecular Neuro-Oncology and Hermelin Brain Tumor Center, Henry Ford Hospital, Detroit, MI
| | - Laila M Poisson
- Department of Public Health Sciences, Henry Ford Hospital, Detroit, MI
| | | | - Sandra Cottingham
- Department of Neuropathology and Clinical Neurosciences, Spectrum Health System, Grand Rapids, MI
| | - Sandra A Rempel
- Department of Neurosurgery, Barbara Jane Levy Laboratory of Molecular Neuro-Oncology and Hermelin Brain Tumor Center, Henry Ford Hospital, Detroit, MI.,Department of Clinical Neurosciences, Laboratory of Molecular Neuro-Oncology, Division of Neurosurgery, Spectrum Health System, Grand Rapids, MI
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Bourne AR, Mohan G, Stone MF, Pham MQ, Schultz CR, Meyerhoff JL, Lumley LA. Olfactory cues increase avoidance behavior and induce Fos expression in the amygdala, hippocampus and prefrontal cortex of socially defeated mice. Behav Brain Res 2013; 256:188-96. [PMID: 23968590 DOI: 10.1016/j.bbr.2013.08.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 08/10/2013] [Accepted: 08/13/2013] [Indexed: 11/29/2022]
Abstract
Genes and proteins of the Fos family are used as markers of neuronal activity and can be modulated by stress. This study investigated whether social defeat (SD) or exposure to an olfactory cue associated with the SD experience activated Fos and FosB/DeltaFosB (ΔFosB) expression in brain regions implicated in the development of post-traumatic stress disorder. Mice exposed to acute SD showed more Fos positive cells in the basolateral amygdala (BLA), CA1 of the hippocampus and the medial prefrontal cortex (mPFC) 1h after SD, and had greater expression of the more persistent FosB/ΔFosB protein in the BLA 24 h after SD compared to controls. Mice exposed to an olfactory cue 24 h or 7 days after SD had higher levels of Fos expression in all three regions 1h after exposure to the cue, and displayed increased avoidance behavior compared to controls. While the avoidance response dissipated with time (less at 7 day vs 24 h after social defeat), Fos expression in the mPFC and CA1 in response to an olfactory cue was greater at 7 days relative to 24 h after social defeat. The results suggest additional processing of the cue-stress association and may provide further support for a role of the mPFC in fear inhibition. These findings may have implications for brain regions and circuitry involved in the avoidance of cues associated with a stressful event that may lead to context-dependent adaptive or maladaptive behavior.
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Affiliation(s)
- A R Bourne
- US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010-5400, USA
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Alam R, Schultz CR, Golembieski WA, Poisson LM, Rempel SA. PTEN suppresses SPARC-induced pMAPKAPK2 and inhibits SPARC-induced Ser78 HSP27 phosphorylation in glioma. Neuro Oncol 2013; 15:451-61. [PMID: 23382286 DOI: 10.1093/neuonc/nos326] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Secreted protein acidic and rich in cysteine (SPARC) is overexpressed in astrocytomas (World Health Organization grades II-IV). We previously demonstrated that SPARC promotes glioma migration and invasion-in part, by activating the P38 mitogen-activated protein kinase (MAPK)-heat shock protein (HSP)27 signaling pathway. The commonly lost tumor suppressor phosphatase and tensin homolog (PTEN) suppresses SPARC-induced migration, which is accompanied by suppression of Shc-Ras-Raf-MEK-ERK1/2 and Akt signaling. As PTEN completely suppresses SPARC-induced migration, we proposed that PTEN must also interfere with SPARC-induced HSP27 signaling. Therefore, this study determined the effects of PTEN expression on SPARC-induced expression and phosphorylation of HSP27. METHODS Control and SPARC-expressing clones transfected with control- or PTEN-expression plasmids were plated on fibronectin-coated tissue culture plates for 3, 6, 24, and 48 h and then lysed. Equal amounts of protein were subjected to Western blot and densitometric analyses. RESULTS The results show that SPARC enhances phosphorylated (p)P38 MAPK, phosphorylated MAPK-activated protein kinase 2 (pMAPKAPK2), and serine (Ser)78 HSP27 phosphorylation relative to total HSP27. PTEN suppresses pAkt and pMAPKAPK2, suggesting that PTEN effects are downstream of pP38 MAPK. PTEN suppressed SPARC-induced sustained phosphorylation at Ser78 HSP27. As the level of total HSP27 differed based on the presence of SPARC or PTEN, the ratios of phosphorylation-specific to total HSP27 were examined. The data demonstrate that SPARC-induced phosphorylation at Ser78 remains elevated despite increasing levels of total HSP27. In contrast, PTEN inhibits SPARC-induced increases in Ser78 HSP27 phosphorylation relative to total HSP27. CONCLUSION These data describe a novel mechanism whereby PTEN inhibits SPARC-induced migration through suppression and differential regulation of pAkt and the P38 MAPK-MAPKAPK2-HSP27 signaling pathway.
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Affiliation(s)
- Ridwan Alam
- Barbara Jane Levy Laboratory of Molecular Neuro-Oncology, Hermelin Brain Tumor Center, Department of Neurosurgery, Education and Research Bldg., Henry Ford Hospital, 2799 West Grand Blvd., Detroit, MI 48202, USA
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Schultz CR, Golembieski WA, King DA, Brown SL, Brodie C, Rempel SA. Inhibition of HSP27 alone or in combination with pAKT inhibition as therapeutic approaches to target SPARC-induced glioma cell survival. Mol Cancer 2012; 11:20. [PMID: 22480225 PMCID: PMC3349587 DOI: 10.1186/1476-4598-11-20] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Accepted: 04/05/2012] [Indexed: 12/18/2022] Open
Abstract
Background The current treatment regimen for glioma patients is surgery, followed by radiation therapy plus temozolomide (TMZ), followed by 6 months of adjuvant TMZ. Despite this aggressive treatment regimen, the overall survival of all surgically treated GBM patients remains dismal, and additional or different therapies are required. Depending on the cancer type, SPARC has been proposed both as a therapeutic target and as a therapeutic agent. In glioma, SPARC promotes invasion via upregulation of the p38 MAPK/MAPKAPK2/HSP27 signaling pathway, and promotes tumor cell survival by upregulating pAKT. As HSP27 and AKT interact to regulate the activity of each other, we determined whether inhibition of HSP27 was better than targeting SPARC as a therapeutic approach to inhibit both SPARC-induced glioma cell invasion and survival. Results Our studies found the following. 1) SPARC increases the expression of tumor cell pro-survival and pro-death protein signaling in balance, and, as a net result, tumor cell survival remains unchanged. 2) Suppressing SPARC increases tumor cell survival, indicating it is not a good therapeutic target. 3) Suppressing HSP27 decreases tumor cell survival in all gliomas, but is more effective in SPARC-expressing tumor cells due to the removal of HSP27 inhibition of SPARC-induced pro-apoptotic signaling. 4) Suppressing total AKT1/2 paradoxically enhanced tumor cell survival, indicating that AKT1 or 2 are poor therapeutic targets. 5) However, inhibiting pAKT suppresses tumor cell survival. 6) Inhibiting both HSP27 and pAKT synergistically decreases tumor cell survival. 7) There appears to be a complex feedback system between SPARC, HSP27, and AKT. 8) This interaction is likely influenced by PTEN status. With respect to chemosensitization, we found the following. 1) SPARC enhances pro-apoptotic signaling in cells exposed to TMZ. 2) Despite this enhanced signaling, SPARC protects cells against TMZ. 3) This protection can be reduced by inhibiting pAKT. 4) Combined inhibition of HSP27 and pAKT is more effective than TMZ treatment alone. Conclusions We conclude that inhibition of HSP27 alone, or in combination with pAKT inhibitor IV, may be an effective therapeutic approach to inhibit SPARC-induced glioma cell invasion and survival in SPARC-positive/PTEN-wildtype and SPARC-positive/PTEN-null tumors, respectively.
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Affiliation(s)
- Chad R Schultz
- The Barbara Jane Levy Laboratory of Molecular Neuro-Oncology, Henry Ford Hospital, Detroit, MI 48202, USA
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Weaver M, Workman G, Schultz CR, Lemke N, Rempel SA, Sage EH. Proteolysis of the matricellular protein hevin by matrix metalloproteinase-3 produces a SPARC-like fragment (SLF) associated with neovasculature in a murine glioma model. J Cell Biochem 2012; 112:3093-102. [PMID: 21688302 DOI: 10.1002/jcb.23235] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The matricellular SPARC-family member hevin (Sparc-like 1/SPARCL-1/SC1/Mast9) contributes to neural development and alters tumor progression in a range of mammalian models. Based on sequence similarity, we hypothesized that proteolytic digestion of hevin would result in SPARC-like fragments (SLF) that affect the activity and/or location of these proteins. Incubation of hevin with matrix metalloproteinase-3 (MMP-3), a protease known to cleave SPARC, produced a limited number of peptides. Sequencing revealed the major proteolytic products to be SPARC-like in primary structure. In gliomas implanted into murine brain, a SLF was associated with SPARC in the neovasculature but not with hevin, the latter prominent in the astrocytes encompassed by infiltrating tumor. In this model of invasive glioma that involves MMP-3 activity, host-derived SLF was not observed in the extracellular matrix adjacent to tumor cells. In contrast, it occurred with its homolog SPARC in the angiogenic response to the tumor. We conclude that MMP-3-derived SLF is a marker of neovessels in glioma, where it could influence the activity of SPARC.
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Affiliation(s)
- Matt Weaver
- Benaroya Research Institute, 1201 Ninth Avenue, Seattle, Washington 98101, USA
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McClung HM, Golembieski WA, Schultz CR, Jankowski M, Schultz LR, Rempel SA. Deletion of the SPARC acidic domain or EGF-like module reduces SPARC-induced migration and signaling through p38 MAPK/HSP27 in glioma. Carcinogenesis 2011; 33:275-84. [PMID: 22114076 DOI: 10.1093/carcin/bgr276] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
We previously demonstrated that secreted protein acidic and rich in cysteine (SPARC) increases heat shock protein 27 (HSP27) expression and phosphorylation and promotes glioma cell migration through the p38 mitogen-activated protein kinase (MAPK)/HSP27 signaling pathway. As different regions of the SPARC protein mediate different SPARC functions, elucidating which SPARC domains regulate HSP27 expression, signaling and migration might provide potential therapeutic strategies to target these functions. To investigate the roles of specific domains, we used an SPARC-green fluorescent protein (GFP) fusion protein and constructs of SPARC-GFP with deletions of either the acidic domain (ΔAcidic) or the epidermal growth factor (EGF)-like module (ΔEGF). GFP, SPARC-GFP and the two deletion mutants were expressed in U87MG glioma cells. Characterization of the derived stable clones by confocal imaging and western blotting suggests proper folding, processing and secretion of the deletion constructs. Uptake of the constructs by naive cells suggests enhanced internalization of ΔAcidic and reduced internalization of ΔEGF. Wound and transwell migration assays and western blot analysis confirm our previous results and indicate that ΔAcidic reduces SPARC-induced migration and p38 MAPK/HSP27 signaling and ΔEGF decreases SPARC-induced migration and dramatically decreases the expression and phosphorylation of HSP27 but is poorly internalized. Loss of the EGF-like module suppresses the enhanced HSP27 protein stability conferred by SPARC. In conclusion, deletions of the acidic domain and EGF-like module have differential effects on cell surface binding and HSP27 protein stability; however, both regions regulate SPARC-induced migration and signaling through HSP27. Our data link the domains of SPARC with different functions and suggest one or both of the constructs as potential therapeutic agents to inhibit SPARC-induced migration.
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Affiliation(s)
- Heather M McClung
- Hermelin Brain Tumor Center, Department of Neurosurgery, Henry Ford Hospital, Detroit, MI 48202, USA
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Golembieski WA, Thomas SL, Schultz CR, Yunker CK, McClung HM, Lemke N, Cazacu S, Barker T, Sage EH, Brodie C, Rempel SA. HSP27 mediates SPARC-induced changes in glioma morphology, migration, and invasion. Glia 2008; 56:1061-75. [PMID: 18442089 DOI: 10.1002/glia.20679] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Secreted protein acidic and rich in cysteine (SPARC) regulates cell-extracellular matrix interactions that influence cell adhesion and migration. We have demonstrated that SPARC is highly expressed in human gliomas, and it promotes brain tumor invasion in vitro and in vivo. To further our understanding regarding SPARC function in glioma migration, we transfected SPARC-green fluorescent protein (GFP) and control GFP vectors into U87MG cells, and assessed the effects of SPARC on cell morphology, migration, and invasion after 24 h. The expression of SPARC was associated with elongated cell morphology, and increased migration and invasion. The effects of SPARC on downstream signaling were assessed from 0 to 6 h and 24 h. SPARC increased the levels of total and phosphorylated HSP27; the latter was preceded by activation of p38 MAPK and inhibited by the p38 MAPK inhibitor SB203580. Augmented expression of SPARC was correlated with increased levels of HSP27 mRNA. In a panel of glioma cell lines, increasing levels of SPARC correlated with increasing total and phosphorylated HSP27. SPARC and HSP27 were colocalized to invading cells in vivo. Inhibition of HSP27 mRNA reversed the SPARC-induced changes in cell morphology, migration, and invasion in vitro. These data indicate that HSP27, a protein that regulates actin polymerization, cell contraction, and migration, is a novel downstream effector of SPARC-regulated cell morphology and migration. As such, it is a potential therapeutic target to inhibit SPARC-induced glioma invasion.
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Affiliation(s)
- William A Golembieski
- Barbara Jane Levy Laboratory of Molecular Neuro-Oncology, Department of Neurosurgery, Henry Ford Hospital, Detroit, Michigan 48202, USA
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Yunker CK, Golembieski W, Lemke N, Schultz CR, Cazacu S, Brodie C, Rempel SA. SPARC-induced increase in glioma matrix and decrease in vascularity are associated with reduced VEGF expression and secretion. Int J Cancer 2008; 122:2735-43. [PMID: 18350569 PMCID: PMC3644882 DOI: 10.1002/ijc.23450] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2007] [Accepted: 12/27/2007] [Indexed: 11/23/2022]
Abstract
Glioblastomas are heterogeneous tumors displaying regions of necrosis, proliferation, angiogenesis, apoptosis and invasion. SPARC, a matricellular protein that negatively regulates angiogenesis and cell proliferation, but enhances cell deadhesion from matrix, is upregulated in gliomas (Grades II-IV). We previously demonstrated that SPARC promotes invasion while concomitantly decreasing tumor growth, in part by decreasing proliferation of the tumor cells. In other cancer types, SPARC has been shown to influence tumor growth by altering matrix production, and by decreasing angiogenesis via interfering with the VEGF-VEGFR1 signaling pathway. We therefore examined whether the SPARC-induced decrease in glioma tumor growth was also, in part, due to alterations in matrix and/or decreased vascularity, and assessed SPARC-VEGF interactions. The data demonstrate that SPARC upregulates glioma matrix, collagen I is a constituent of the matrix and SPARC promotes collagen fibrillogenesis. Furthermore, SPARC suppressed glioma vascularity, and this was accompanied by decreased VEGF expression and secretion, which was, in part, due to reduced VEGF165 transcript abundance. These data indicate that SPARC modulates glioma growth by altering the tumor microenvironment and by suppressing tumor vascularity through suppression of VEGF expression and secretion. These experiments implicate a novel mechanism, whereby SPARC regulates VEGF function by limiting the available growth factor. Because SPARC is considered to be a therapeutic target for gliomas, a further understanding of its complex signaling mechanisms is important, as targeting SPARC to decrease invasion could undesirably lead to the growth of more vascular and proliferative tumors.
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Affiliation(s)
- Christopher K Yunker
- Barbara Jane Levy Laboratory of Molecular Neuro-Oncology, Hermelin Brain Tumor Center, Department of Neurosurgery, Henry Ford HospitalDetroit, MI
| | - William Golembieski
- Barbara Jane Levy Laboratory of Molecular Neuro-Oncology, Hermelin Brain Tumor Center, Department of Neurosurgery, Henry Ford HospitalDetroit, MI
| | - Nancy Lemke
- Barbara Jane Levy Laboratory of Molecular Neuro-Oncology, Hermelin Brain Tumor Center, Department of Neurosurgery, Henry Ford HospitalDetroit, MI
| | - Chad R Schultz
- Barbara Jane Levy Laboratory of Molecular Neuro-Oncology, Hermelin Brain Tumor Center, Department of Neurosurgery, Henry Ford HospitalDetroit, MI
| | - Simona Cazacu
- William and Karen Davidson Laboratory of Cell Signaling and Tumorigenesis, Hermelin Brain Tumor Center, Department of Neurosurgery, Henry Ford HospitalDetroit, MI
| | - Chaya Brodie
- William and Karen Davidson Laboratory of Cell Signaling and Tumorigenesis, Hermelin Brain Tumor Center, Department of Neurosurgery, Henry Ford HospitalDetroit, MI
| | - Sandra A Rempel
- Barbara Jane Levy Laboratory of Molecular Neuro-Oncology, Hermelin Brain Tumor Center, Department of Neurosurgery, Henry Ford HospitalDetroit, MI
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Rempel SA, Hawley RC, Gutiérrez JA, Mouzon E, Bobbitt KR, Lemke N, Schultz CR, Schultz LR, Golembieski W, Koblinski J, VanOsdol S, Miller CG. Splenic and immune alterations of the Sparc-null mouse accompany a lack of immune response. Genes Immun 2007; 8:262-74. [PMID: 17344888 DOI: 10.1038/sj.gene.6364388] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Sparc-null mice have been used as models to assess tumor-host immune cell interactions. However, it is not known if they have a competent immune system. In this study, the immune systems of Sparc wild-type and null mice were compared. Mice were assessed for differences in total body weight, spleen weight and spleen-to-body weight ratios. Spleens were compared with respect to morphology, and Sparc, Ki-67, MOMA-1 and IgM expression. Immune cells in blood, bone marrow and spleen were assessed by blood smears, automated blood panel, and flow cytometry. Additionally, the ability of Sparc-null mice to respond to immune challenge was evaluated using a footpad model. The morphological and immunohistochemical results indicated that Sparc-null spleens had more white pulp, hyperproliferative B cells in the germinal centers, and decreased marginal zones. Sparc-null spleens lacked normal Sparc expression in red and white pulp, marginal zones, endothelial and sinusoidal cells. By flow analysis, B cells were decreased and T cells were increased in the bone marrow. Finally, Sparc-null mice were unable to mount an immune response following footpad lipopolysaccharide challenge. These data confirm that Sparc-null mice have an impaired immune system.
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Affiliation(s)
- S A Rempel
- Department of Neurosurgery, Barbara Jane Levy Laboratory of Molecular Neuro-Oncology, Hermelin Brain Tumor Center, Henry Ford Hospital, Detroit, MI, USA.
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