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Gambari R, Waziri AD, Goonasekera H, Peprah E. Pharmacogenomics of Drugs Used in β-Thalassemia and Sickle-Cell Disease: From Basic Research to Clinical Applications. Int J Mol Sci 2024; 25:4263. [PMID: 38673849 PMCID: PMC11050010 DOI: 10.3390/ijms25084263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 03/30/2024] [Accepted: 04/04/2024] [Indexed: 04/28/2024] Open
Abstract
In this short review we have presented and discussed studies on pharmacogenomics (also termed pharmacogenetics) of the drugs employed in the treatment of β-thalassemia or Sickle-cell disease (SCD). This field of investigation is relevant, since it is expected to help clinicians select the appropriate drug and the correct dosage for each patient. We first discussed the search for DNA polymorphisms associated with a high expression of γ-globin genes and identified this using GWAS studies and CRISPR-based gene editing approaches. We then presented validated DNA polymorphisms associated with a high HbF production (including, but not limited to the HBG2 XmnI polymorphism and those related to the BCL11A, MYB, KLF-1, and LYAR genes). The expression of microRNAs involved in the regulation of γ-globin genes was also presented in the context of pharmacomiRNomics. Then, the pharmacogenomics of validated fetal hemoglobin inducers (hydroxyurea, butyrate and butyrate analogues, thalidomide, and sirolimus), of iron chelators, and of analgesics in the pain management of SCD patients were considered. Finally, we discuss current clinical trials, as well as international research networks focusing on clinical issues related to pharmacogenomics in hematological diseases.
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Affiliation(s)
- Roberto Gambari
- Center “Chiara Gemmo and Elio Zago” for the Research on Thalassemia, Department of Life Sciences and Biotechnology, Ferrara University, 40124 Ferrara, Italy
| | - Aliyu Dahiru Waziri
- Department of Hematology and Blood Transfusion, Ahmadu Bello University Teaching Hospital Zaria, Kaduna 810001, Nigeria;
| | - Hemali Goonasekera
- Department of Anatomy, Genetics and Biomedical Informatics, Faculty of Medicine, University of Colombo, Colombo P.O. Box 271, Sri Lanka;
| | - Emmanuel Peprah
- Implementing Sustainable Evidence-Based Interventions through Engagement (ISEE) Lab, Department of Global and Environmental Health, School of Global Public Health, New York University, New York, NY 10003, USA;
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Heydari N, Shariati L, Khanahmad H, Hejazi Z, Shahbazi M, Salehi M. Gamma reactivation using the spongy effect of KLF1-binding site sequence: an approach in gene therapy for beta-thalassemia. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2016; 19:1063-1069. [PMID: 27872702 PMCID: PMC5110654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
OBJECTIVES β-thalassemia is one of the most common genetic disorders in the world. As one of the promising treatment strategies, fetal hemoglobin (Hb F) can be induced. The present study was an attempt to reactivate the γ-globin gene by introducing a gene construct containing KLF1 binding sites to the K562 cell line. MATERIALS AND METHODS A plasmid containing a 192 bp sequence with two repeats of KLF1 binding sites on β-globin and BCL11A promoters was constructed and used to transfect the K562 cell line. Positive selection was performed under treatment with 150 μg/ml hygromycin B. The remaining cells were expanded and harvested on day 28, and genomic DNA was extracted. The PCR was carried out to verify insertion of DNA fragment to the genome of K562 cells. The cells were differentiated with 15 μg/ml cisplatin. Flowcytometry was performed to identify erythroid differentiation by detection of CD235a+ cells. Real-time RT-PCR was performed to evaluate γ-globin expression in the transfected cells. RESULTS A 1700 bp fragment was observed on agarose gel as expected and insertion of DNA fragment to the genome of K562 cells was verified. Totally, 84% of cells were differentiated. The transfected cells significantly increased γ-globin expression after differentiation compared to untransfected ones. CONCLUSION The findings demonstrate that the spongy effect of KLF1-binding site on BCL11A and β-globin promoters can induce γ-globin expression in K562 cells. This novel strategy can be promising for the treatment of β-thalassemia and sickle cell disease.
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Affiliation(s)
- Nasrin Heydari
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Laleh Shariati
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hossein Khanahmad
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran,Pediatric Inherited Diseases Research Center, Research Institute for Primordial Prevention of Non-communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran,Corresponding author: Hossein Khanahmad. Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran. Tel: +98-311-37922487; Fax: +98-311-3668859;
| | - Zahra Hejazi
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mansoureh Shahbazi
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mansoor Salehi
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
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Moos WH, Maneta E, Pinkert CA, Irwin MH, Hoffman ME, Faller DV, Steliou K. Epigenetic Treatment of Neuropsychiatric Disorders: Autism and Schizophrenia. Drug Dev Res 2016; 77:53-72. [PMID: 26899191 DOI: 10.1002/ddr.21295] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Neuropsychiatric disorders are a heterogeneous group of conditions that often share underlying mitochondrial dysfunction and biological pathways implicated in their pathogenesis, progression, and treatment. To date, these disorders have proven notoriously resistant to molecular-targeted therapies, and clinical options are relegated to interventional types, which do not address the core symptoms of the disease. In this review, we discuss emerging epigenetic-driven approaches using novel acylcarnitine esters (carnitinoids) that act on master regulators of antioxidant and cytoprotective genes and mitophagic pathways. These carnitinoids are actively transported, mitochondria-localizing, biomimetic coenzyme A surrogates of short-chain fatty acids, which inhibit histone deacetylase and may reinvigorate synaptic plasticity and protect against neuronal damage. We outline these neuroprotective effects in the context of treatment of neuropsychiatric disorders such as autism spectrum disorder and schizophrenia.
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Affiliation(s)
- Walter H Moos
- Department of Pharmaceutical Chemistry, School of Pharmacy, University of California San Francisco, San Francisco, CA, USA.,SRI Biosciences, A Division of SRI International, Menlo Park, CA, USA
| | - Eleni Maneta
- Department of Psychiatry, Boston Children's Hospital, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
| | - Carl A Pinkert
- Department of Biological Sciences, College of Arts and Sciences, The University of Alabama, Tuscaloosa, AL, USA.,Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA
| | - Michael H Irwin
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA
| | - Michelle E Hoffman
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA
| | - Douglas V Faller
- Cancer Research Center, Boston University School of Medicine, Boston, MA, USA
| | - Kosta Steliou
- Cancer Research Center, Boston University School of Medicine, Boston, MA, USA.,PhenoMatriX, Inc., Boston, MA, USA
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Boosalis MS, Sangerman JI, White GL, Wolf RF, Shen L, Dai Y, White E, Makala LH, Li B, Pace BS, Nouraie M, Faller DV, Perrine SP. Novel Inducers of Fetal Globin Identified through High Throughput Screening (HTS) Are Active In Vivo in Anemic Baboons and Transgenic Mice. PLoS One 2015; 10:e0144660. [PMID: 26713848 PMCID: PMC4694699 DOI: 10.1371/journal.pone.0144660] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 11/20/2015] [Indexed: 02/07/2023] Open
Abstract
High-level fetal (γ) globin expression ameliorates clinical severity of the beta (β) hemoglobinopathies, and safe, orally-bioavailable γ-globin inducing agents would benefit many patients. We adapted a LCR-γ-globin promoter-GFP reporter assay to a high-throughput robotic system to evaluate five diverse chemical libraries for this activity. Multiple structurally- and functionally-diverse compounds were identified which activate the γ-globin gene promoter at nanomolar concentrations, including some therapeutics approved for other conditions. Three candidates with established safety profiles were further evaluated in erythroid progenitors, anemic baboons and transgenic mice, with significant induction of γ-globin expression observed in vivo. A lead candidate, Benserazide, emerged which demonstrated > 20-fold induction of γ-globin mRNA expression in anemic baboons and increased F-cell proportions by 3.5-fold in transgenic mice. Benserazide has been used chronically to inhibit amino acid decarboxylase to enhance plasma levels of L-dopa. These studies confirm the utility of high-throughput screening and identify previously unrecognized fetal globin inducing candidates which can be developed expediently for treatment of hemoglobinopathies.
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Affiliation(s)
- Michael S. Boosalis
- Cancer Center and Hemoglobinopathy Thalassemia Research Unit, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Jose I. Sangerman
- Cancer Center and Hemoglobinopathy Thalassemia Research Unit, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Gary L. White
- Department of Comparative Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Roman F. Wolf
- Department of Comparative Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Ling Shen
- Cancer Center and Hemoglobinopathy Thalassemia Research Unit, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Yan Dai
- Cancer Center and Hemoglobinopathy Thalassemia Research Unit, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Emily White
- Department of Comparative Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Levi H. Makala
- Department of Pediatrics, Georgia Regents University, Augusta, Georgia, United States of America
| | - Biaoru Li
- Department of Pediatrics, Georgia Regents University, Augusta, Georgia, United States of America
| | - Betty S. Pace
- Department of Pediatrics, Georgia Regents University, Augusta, Georgia, United States of America
| | - Mehdi Nouraie
- Department of Medicine, Center for Sickle Cell Disease, Howard University, Washington, DC, United States of America
| | - Douglas V. Faller
- Cancer Center and Hemoglobinopathy Thalassemia Research Unit, Boston University School of Medicine, Boston, Massachusetts, United States of America
- Phoenicia BioSciences, Weston, Massachusetts, United States of America
| | - Susan P. Perrine
- Cancer Center and Hemoglobinopathy Thalassemia Research Unit, Boston University School of Medicine, Boston, Massachusetts, United States of America
- Phoenicia BioSciences, Weston, Massachusetts, United States of America
- * E-mail:
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5
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Dai Y, Sangerman J, Luo HY, Fucharoen S, Chui DHK, Faller DV, Perrine SP. Therapeutic fetal-globin inducers reduce transcriptional repression in hemoglobinopathy erythroid progenitors through distinct mechanisms. Blood Cells Mol Dis 2015; 56:62-9. [PMID: 26603726 DOI: 10.1016/j.bcmd.2015.10.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 10/26/2015] [Indexed: 12/15/2022]
Abstract
Pharmacologic augmentation of γ-globin expression sufficient to reduce anemia and clinical severity in patients with diverse hemoglobinopathies has been challenging. In studies here, representative molecules from four chemical classes, representing several distinct primary mechanisms of action, were investigated for effects on γ-globin transcriptional repressors, including components of the NuRD complex (LSD1 and HDACs 2-3), and the downstream repressor BCL11A, in erythroid progenitors from hemoglobinopathy patients. Two HDAC inhibitors (MS-275 and SB939), a short-chain fatty acid derivative (sodium dimethylbutyrate [SDMB]), and an agent identified in high-throughput screening, Benserazide, were studied. These therapeutics induced γ-globin mRNA in progenitors above same subject controls up to 20-fold, and increased F-reticulocytes up to 20%. Cellular protein levels of BCL11A, LSD-1, and KLF1 were suppressed by the compounds. Chromatin immunoprecipitation assays demonstrated a 3.6-fold reduction in LSD1 and HDAC3 occupancy in the γ-globin gene promoter with Benserazide exposure, 3-fold reduction in LSD-1 and HDAC2 occupancy in the γ-globin gene promoter with SDMB exposure, while markers of gene activation (histone H3K9 acetylation and H3K4 demethylation), were enriched 5.7-fold. These findings identify clinical-stage oral therapeutics which inhibit or displace major co-repressors of γ-globin gene transcription and may suggest a rationale for combination therapy to produce enhanced efficacy.
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Affiliation(s)
- Yan Dai
- Hemoglobinopathy Thalassemia Research Unit and Cancer Center, Boston University School of Medicine, Boston, MA, United States
| | - Jose Sangerman
- Hemoglobinopathy Thalassemia Research Unit and Cancer Center, Boston University School of Medicine, Boston, MA, United States
| | - Hong Yuan Luo
- Department of Laboratory Medicine, Boston University School of Medicine, Boston, MA, United States
| | - Suthat Fucharoen
- Thalassemia Research Center, Mahidol University, Phuttamonthon, Thailand
| | - David H K Chui
- Department of Laboratory Medicine, Boston University School of Medicine, Boston, MA, United States
| | - Douglas V Faller
- Hemoglobinopathy Thalassemia Research Unit and Cancer Center, Boston University School of Medicine, Boston, MA, United States; Phoenicia BioSciences, Inc., Newton, MA, United States
| | - Susan P Perrine
- Hemoglobinopathy Thalassemia Research Unit and Cancer Center, Boston University School of Medicine, Boston, MA, United States; Phoenicia BioSciences, Inc., Newton, MA, United States; Center for Hemoglobin Research in Minorities, Departments of Pediatrics and Medicine, Howard University College of Medicine, Washington DC, United States.
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6
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Bioprotective Carnitinoids: Lipoic Acid, Butyrate, and Mitochondria-Targeting to Treat Radiation Injury: Mitochondrial Drugs Come of Age. Drug Dev Res 2015; 76:167-75. [DOI: 10.1002/ddr.21258] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Accepted: 05/28/2015] [Indexed: 12/16/2022]
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Thompson KW, Marquez SB, Lu L, Reisman D. Induction of functional Brm protein from Brm knockout mice. Oncoscience 2015; 2:349-61. [PMID: 26097869 PMCID: PMC4468321 DOI: 10.18632/oncoscience.153] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2015] [Accepted: 04/08/2015] [Indexed: 12/18/2022] Open
Abstract
Once the knockout of the Brm gene was found to be nontumorigenic in mice, the study of BRM's involvement in cancer seemed less important compared with that of its homolog, Brg1. This has likely contributed to the disparity that has been observed in the publication ratio between BRG1 and BRM. We show that a previously published Brm knockout mouse is an incomplete knockout whereby a truncated isoform of Brm is detected in normal tissue and in tumors. We show that this truncated Brm isoform has functionality comparable to wild type Brm. By immunohistochemistry (IHC), this truncated Brm is undetectable in normal lung tissue and is minimal to very low in Brmnull tumors. However, it is significant in a subset (~40%) of Brg1/Brm double knockout (DKO) tumors that robustly express this truncated BRM, which in part stems from an increase in Brm mRNA levels. Thus, it is likely that this mutant mouse model does not accurately reflect the role that Brm plays in cancer development. We suggest that the construction of a completely new mouse Brm knockout, where Brm is functionally absent, is needed to determine whether or not Brm is actually tumorigenic and if Brm might be a tumor suppressor.
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Affiliation(s)
- Kenneth W. Thompson
- Division of Hematology and Oncology, Department of Medicine, University of Florida, Gainesville, Florida, USA
| | - Stefanie B. Marquez
- Division of Hematology and Oncology, Department of Medicine, University of Florida, Gainesville, Florida, USA
| | - Li Lu
- Department of Pathology, University of Florida, Gainesville, Florida, USA
| | - David Reisman
- Division of Hematology and Oncology, Department of Medicine, University of Florida, Gainesville, Florida, USA
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8
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Perrine SP, Pace BS, Faller DV. Targeted fetal hemoglobin induction for treatment of beta hemoglobinopathies. Hematol Oncol Clin North Am 2014; 28:233-48. [PMID: 24589264 DOI: 10.1016/j.hoc.2013.11.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Fetal globin (gamma globin; HBG) is normally expressed during fetal life and prevents the clinical manifestations of beta hemoglobinopathies before birth. HBG genes are normally integrated in hematopoietic stem cells in all humans, and are at least partially amenable to reactivation. Inducing expression of fetal globin (HBG) gene expression to 60% to 70% of alpha globin synthesis produces a β-thalassemia trait phenotype, and reduces anemia. Tailoring combinations of therapeutics to patient subsets characterized for quantitative trait loci which modulate basal fetal hemoglobin and erythroid cell survival should provide effective amelioration of clinical symptoms in β-thalassemia and sickle cell disease.
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Affiliation(s)
- Susan P Perrine
- Hemoglobinopathy-Thalassemia Research Unit, Cancer Center, Department of Medicine, Pediatrics, Pharmacology and Experimental Therapeutics, Boston University School of Medicine, 72 East Concord Street, L-909, Boston, MA 02118, USA.
| | - Betty S Pace
- Department of Pediatrics and Biochemistry and Molecular Biology, Georgia Regents University, Augusta, GA 30912, USA
| | - Douglas V Faller
- Cancer Center, Boston University School of Medicine, Boston, MA 02118, USA
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9
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Reid ME, El Beshlawy A, Inati A, Kutlar A, Abboud MR, Haynes J, Ward R, Sharon B, Taher AT, Smith W, Manwani D, Ghalie RG. A double-blind, placebo-controlled phase II study of the efficacy and safety of 2,2-dimethylbutyrate (HQK-1001), an oral fetal globin inducer, in sickle cell disease. Am J Hematol 2014; 89:709-13. [PMID: 24677033 DOI: 10.1002/ajh.23725] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 03/24/2014] [Accepted: 03/26/2014] [Indexed: 02/05/2023]
Abstract
This placebo-controlled phase II study evaluated the pharmacodynamics, efficacy and safety of 2,2-dimethylbutyrate (HQK-1001), a fetal globin gene-inducing short-chain fatty acid derivative, administered orally at 15 mg/kg twice daily for 48 weeks in 76 subjects with sickle cell disease (SCD). The median age was 26 years (range: 12-55 years) and 37 subjects (49%) were treated previously with hydroxycarbamide. Sixty subjects (79%) had Hb SS and 16 (21%) had S/β(0) thalassemia. The study was terminated after a planned interim analysis showed no significant increase in fetal hemoglobin (Hb F) and a trend for more pain crises in the HQK-1001 group. For 54 subjects with Week 24 data, the mean absolute increase in Hb F was 0.9% (95% confidence interval (CI): 0.1-1.6%) with HQK-1001 and 0.2% (95% CI: -0.7-1.1%) with placebo. Absolute increases in Hb F greater than 3% were noted in 9 of 38 subjects (24%) administered HQK-1001 and 1 of 38 subjects (3%) administered placebo. The mean changes in hemoglobin at Week 24 were comparable between the two groups. The mean annualized rate of pain crises was 3.5 with HQK-1001 and 1.7 with placebo. The most common adverse events in the HQK-1001 group, usually graded as mild or moderate, consisted of nausea, headache, vomiting, abdominal pain, and fatigue. Additional studies of HQK-1001 at this dose and schedule are not recommended in SCD. Intermittent HQK-1001 administration, rather than a daily regimen, may be better tolerated and more effective, as shown previously with arginine butyrate, and warrants further evaluation.
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Affiliation(s)
- Marvin E. Reid
- Sickle Cell Unit; University of West Indies; Mona Jamaica
| | | | - Adlette Inati
- Rafik Hariri University Medical Center; Beirut Lebanon
| | - Abdullah Kutlar
- Sickle Cell Center at the Medical College of Georgia; Augusta Georgia
| | | | - Johnson Haynes
- Sickle Cell Center at the University of South Alabama; Mobile Alabama
| | | | - Bruce Sharon
- University of Illinois at Chicago; Chicago Illinois
| | | | - Wally Smith
- Sickle Cell Center at Virginia Commonwealth University; Richmond Virginia
| | - Deepa Manwani
- Children's Hospital at Montefiore Medical Center; New York City New York
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Regulation of Gγ-globin gene by ATF2 and its associated proteins through the cAMP-response element. PLoS One 2013; 8:e78253. [PMID: 24223142 PMCID: PMC3819381 DOI: 10.1371/journal.pone.0078253] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 09/10/2013] [Indexed: 01/12/2023] Open
Abstract
The upstream Gγ-globin cAMP-response element (G-CRE) plays an important role in regulating Gγ-globin expression through binding of ATF2 and its DNA-binding partners defined in this study. ATF2 knockdown resulted in a significant reduction of γ-globin expression accompanied by decreased ATF2 binding to the G-CRE. By contrast, stable ATF2 expression in K562 cells increased γ-globin transcription which was reduced by ATF2 knockdown. Moreover, a similar effect of ATF2 on γ-globin expression was observed in primary erythroid progenitors. To understand the role of ATF2 in γ-globin expression, chromatographically purified G-CRE/ATF2-interacting proteins were subjected to mass spectrometry analysis; major binding partners included CREB1, cJun, Brg1, and histone deacetylases among others. Immunoprecipitation assays demonstrated interaction of these proteins with ATF2 and in vivo GCRE binding in CD34+ cells undergoing erythroid differentiation which was correlated with γ-globin expression during development. These results suggest synergism between developmental stage-specific recruitments of the ATF2 protein complex and expression of γ-globin during erythropoiesis. Microarray studies in K562 cells support ATF2 plays diverse roles in hematopoiesis and chromatin remodeling.
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Kutlar A, Reid ME, Inati A, Taher AT, Abboud MR, El-Beshlawy A, Buchanan GR, Smith H, Ataga KI, Perrine SP, Ghalie RG. A dose-escalation phase IIa study of 2,2-dimethylbutyrate (HQK-1001), an oral fetal globin inducer, in sickle cell disease. Am J Hematol 2013; 88:E255-60. [PMID: 23828223 DOI: 10.1002/ajh.23533] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 06/21/2013] [Accepted: 06/25/2013] [Indexed: 01/11/2023]
Abstract
2,2-Dimethylbutyrate (HQK-1001), an orally-bioavailable promoter-targeted fetal globin gene-inducing agent, was evaluated in an open-label, randomized dose-escalation study in 52 subjects with hemoglobin SS or S/β(0) thalassemia. HQK-1001 was administered daily for 26 weeks at 30 mg/kg (n = 15), 40 mg/kg (n = 18) and 50 mg/kg (n = 19), either alone (n = 21) or with hydroxyurea (n = 31). The most common drug-related adverse events were usually mild or moderate and reversible. Gastritis was graded as severe in three subjects at 40 mg/kg and was considered the dose-limiting toxicity. Subsequently all subjects were switched to the maximum tolerated dose of 30 mg/kg. Due to early discontinuations for blood transfusions, adverse events or non-compliance, only 25 subjects (48%) completed the study. Drug plasma concentrations were sustained above targeted levels at 30 mg/kg. Increases in fetal hemoglobin (Hb F) were observed in 42 subjects (80%), and 12 (23%) had increases ≥4%. The mean increase in Hb F was 2% [95% confidence interval (CI), 0.8-3.2%] in 21 subjects receiving HQK-1001 alone and 2.7% (95% CI, 1.7-3.8%) in 31 subjects receiving HQK-1001 plus hydroxyurea. Total hemoglobin increased by a mean of 0.65 g/dL (95% CI, 0.5-1.0 g/dL), and 13 subjects (25%) had increases ≥1 g/dL. Future studies are warranted to evaluate the therapeutic potential of HQK-1001 in sickle cell disease. .
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Affiliation(s)
- Abdullah Kutlar
- Adult Sickle Cell Center, Georgia Regents University Medical Center, Augusta, GA, USA
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Li H, Xie W, Gore ER, Montoute MN, Bee WT, Zappacosta F, Zeng X, Wu Z, Kallal L, Ames RS, Pope AJ, Benowitz A, Erickson-Miller CL. Development of phenotypic screening assays for γ-globin induction using primary human bone marrow day 7 erythroid progenitor cells. ACTA ACUST UNITED AC 2013; 18:1212-22. [PMID: 24163393 DOI: 10.1177/1087057113499776] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Sickle cell anemia (SCA) is a genetic disorder of the β-globin gene. SCA results in chronic ischemia with pain and tissue injury. The extent of SCA symptoms can be ameliorated by treatment with drugs, which result in increasing the levels of γ-globin in patient red blood cells. Hydroxyurea (HU) is a Food and Drug Administration-approved drug for SCA, but it has dose-limiting toxicity, and patients exhibit highly variable treatment responses. To identify compounds that may lead to the development of better and safer medicines, we have established a method using primary human bone marrow day 7 erythroid progenitor cells (EPCs) to screen for compounds that induce γ-globin production. First, human marrow CD34(+) cells were cultured and expanded for 7 days and characterized for the expression of erythroid differentiation markers (CD71, CD36, and CD235a). Second, fresh or cryopreserved EPCs were treated with compounds for 3 days in 384-well plates followed by γ-globin quantification by an enzyme-linked immunosorbent assay (ELISA), which was validated using HU and decitabine. From the 7408 compounds screened, we identified at least one new compound with confirmed γ-globin-inducing activity. Hits are undergoing analysis in secondary assays. In this article, we describe the method of generating fit-for-purpose EPCs; the development, optimization, and validation of the ELISA and secondary assays for γ-globin detection; and screening results.
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Affiliation(s)
- Hu Li
- 1Molecular Discovery Research, GlaxoSmithKline, Collegeville, PA, USA
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Three fingers on the switch: Krüppel-like factor 1 regulation of γ-globin to β-globin gene switching. Curr Opin Hematol 2013; 20:193-200. [PMID: 23474875 DOI: 10.1097/moh.0b013e32835f59ba] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
PURPOSE OF REVIEW Krüppel-like factor 1 (KLF1) regulates most aspects of erythropoiesis. Many years ago, transgenic mouse studies implicated KLF1 in the control of the human γ-globin to β-globin switch. In this review, we will integrate these initial studies with recent developments in human genetics to discuss our present understanding of how KLF1 and its target genes direct the switch. RECENT FINDINGS Recent studies have shown that human mutations in KLF1 are common and mostly asymptomatic, but lead to significant increases in levels of fetal hemoglobin (HbF) (α2γ2) and adult HbA2 (α2δ2). Genome-wide association studies (GWAS) have demonstrated that three primary loci are associated with increased HbF levels in the population: the β-globin locus itself, the BCL11A locus, and a site between MYB and HBS1L. We discuss evidence that KLF1 directly regulates BCL11A, MYB and other genes, which are involved directly or indirectly in γ-globin silencing, thus providing a link between GWAS and KLF1 in hemoglobin switching. SUMMARY KLF1 regulates the γ-globin to β-globin genetic switch by many mechanisms. Firstly, it facilitates formation of an active chromatin hub (ACH) at the β-globin gene cluster. Specifically, KLF1 conscripts the adult-stage β-globin gene to replace the γ-globin gene within the ACH in a stage-specific manner. Secondly, KLF1 acts as a direct activator of genes that encode repressors of γ-globin gene expression. Finally, KLF1 is a regulator of many components of the cell cycle machinery. We suggest that dysregulation of these genes leads to cell cycle perturbation and 'erythropoietic stress' leading to indirect upregulation of HbF.
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Fucharoen S, Inati A, Siritanaratku N, Thein SL, Wargin WC, Koussa S, Taher A, Chaneim N, Boosalis M, Berenson R, Perrine SP. A randomized phase I/II trial of HQK-1001, an oral fetal globin gene inducer, in β-thalassaemia intermedia and HbE/β-thalassaemia. Br J Haematol 2013; 161:587-93. [PMID: 23530969 DOI: 10.1111/bjh.12304] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Accepted: 01/09/2013] [Indexed: 11/29/2022]
Abstract
β-thalassaemia intermedia (BTI) syndromes cause haemolytic anaemia, ineffective erythropoiesis, and widespread complications. Higher fetal globin expression within genotypes reduces globin imbalance and ameliorates anaemia. Sodium 2,2 dimethylbutyrate (HQK-1001), an orally bioavailable short-chain fatty acid derivative, induces γ-globin expression experimentally and is well-tolerated in normal subjects. Accordingly, a randomized, blinded, placebo-controlled, Phase I/II trial was performed in 21 adult BTI patients (14 with HbE/β(0) thalassaemia and seven with β(+)/β(0) thalassaemia intermedia, to determine effective doses for fetal globin induction, safety, and tolerability. HQK-1001 or placebo were administered once daily for 8 weeks at four dose levels (10, 20, 30, or 40 mg/kg per day), and subjects were monitored for laboratory and clinical events. Pharmacokinetic profiles demonstrated a t(1/2) of 10-12 h. Adverse events with HQK-1001 treatment were not significantly different from placebo treatment. The 20 mg/kg treatment doses increased median HbF above baseline levels by 6·6% and 4·4 g/l (P < 0·01) in 8/9 subjects; total haemoglobin (Hb) increased by a mean of 11 g/l in 4/9 subjects. These findings identified a safe oral therapeutic which induces fetal globin in BTI. Further investigation of HQK-1001 with longer dosing to definitively evaluate its haematological potential appears warranted.
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Affiliation(s)
- Suthat Fucharoen
- Thalassemia Research Centre, Mahidol University, Nakhonpathon, Thailand
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Steliou K, Boosalis MS, Perrine SP, Sangerman J, Faller DV. Butyrate histone deacetylase inhibitors. Biores Open Access 2013; 1:192-8. [PMID: 23514803 PMCID: PMC3559235 DOI: 10.1089/biores.2012.0223] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
In addition to being a part of the metabolic fatty acid fuel cycle, butyrate is also capable of inducing growth arrest in a variety of normal cell types and senescence-like phenotypes in gynecological cancer cells, inhibiting DNA synthesis and cell growth in colonic tumor cell lines, suppressing hTERT mRNA expression and telomerase activity in human prostate cancer cells, and inducing stem cell differentiation and apoptosis by DNA fragmentation. It regulates gene expression by inhibiting histone deacetylases (HDACs), enhances memory recovery and formation in mice, stimulates neurogenesis in the ischemic brain, promotes osteoblast formation, selectively blocks cell replication in transformed cells (compared to healthy cells), and can prevent and treat diet-induced obesity and insulin resistance in mouse models of obesity, as well as stimulate fetal hemoglobin expression in individuals with hematologic diseases such as the thalassemias and sickle-cell disease, in addition to a multitude of other biochemical effects in vivo. However, efforts to exploit the potential of butyrate in the clinical treatment of cancer and other medical disorders are thwarted by its poor pharmacological properties (short half-life and first-pass hepatic clearance) and the multigram doses needed to achieve therapeutic concentrations in vivo. Herein, we review some of the methods used to overcome these difficulties with an emphasis on HDAC inhibition.
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Affiliation(s)
- Kosta Steliou
- PhenoMatriX, Inc. , Boston, Massachusetts. ; Cancer Research Center, Boston University School of Medicine , Boston, Massachusetts
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Yien YY, Bieker JJ. EKLF/KLF1, a tissue-restricted integrator of transcriptional control, chromatin remodeling, and lineage determination. Mol Cell Biol 2013; 33:4-13. [PMID: 23090966 PMCID: PMC3536305 DOI: 10.1128/mcb.01058-12] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Erythroid Krüppel-like factor (EKLF or KLF1) is a transcriptional regulator that plays a critical role in lineage-restricted control of gene expression. KLF1 expression and activity are tightly controlled in a temporal and differentiation stage-specific manner. The mechanisms by which KLF1 is regulated encompass a range of biological processes, including control of KLF1 RNA transcription, protein stability, localization, and posttranslational modifications. Intact KLF1 regulation is essential to correctly regulate erythroid function by gene transcription and to maintain hematopoietic lineage homeostasis by ensuring a proper balance of erythroid/megakaryocytic differentiation. In turn, KLF1 regulates erythroid biology by a wide variety of mechanisms, including gene activation and repression by regulation of chromatin configuration, transcriptional initiation and elongation, and localization of gene loci to transcription factories in the nucleus. An extensive series of biochemical, molecular, and genetic analyses has uncovered some of the secrets of its success, and recent studies are highlighted here. These reveal a multilayered set of control mechanisms that enable efficient and specific integration of transcriptional and epigenetic controls and that pave the way for proper lineage commitment and differentiation.
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Affiliation(s)
- Yvette Y. Yien
- Department of Developmental and Regenerative Biology
- Graduate School of Biological Sciences
| | - James J. Bieker
- Department of Developmental and Regenerative Biology
- Black Family Stem Cell Institute
- Tisch Cancer Institute, Mount Sinai School of Medicine, New York, New York, USA
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Kutlar A, Ataga K, Reid M, Vichinsky EP, Neumayr L, Blair-Britt L, Labotka R, Glass J, Keefer JR, Wargin WA, Berenson R, Perrine SP. A phase 1/2 trial of HQK-1001, an oral fetal globin inducer, in sickle cell disease. Am J Hematol 2012; 87:1017-21. [PMID: 22887019 DOI: 10.1002/ajh.23306] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 06/21/2012] [Accepted: 06/25/2012] [Indexed: 12/18/2022]
Abstract
Therapeutics which reduce the pathology in sickle cell syndromes are needed, particularly noncytotoxic therapeutics. Fetal hemoglobin (HbF, α(2) γ(2) ) is established as a major regulator of disease severity; increased HbF levels correlate with milder clinical courses and improved survival. Accordingly, sodium dimethylbutyrate (HQK-1001), an orally-bioavailable, promoter-targeted fetal globin gene-inducing agent, was evaluated in a randomized, blinded, dose-ranging Phase I/II trial in 24 adult patients with HbSS or S/β thalassemia, to determine safety and tolerability of three escalating dose levels. The study therapeutic was administered once daily for two 6-week cycles, with a two-week interim dose holiday. Twenty-one patients completed the study. Five patients received study drug at 10 or 20 mg/kg doses, seven patients received study drug at 30 mg/kg/dose, and 4 patients received placebo. HQK-1001 was well-tolerated with no unexpected drug-related adverse events; a dose-limiting toxicity was not identified. Plasma drug levels were sustained above targeted levels for 24 hr. Increases in HbF above baseline were observed particularly with 30 mg/kg/day doses; in five of seven treated patients, a mean absolute increase in HbF of 0.2 g/dl and a mean increase in total hemoglobin (Hgb) of 0.83 g/dl above baseline were observed, whereas no increases occurred in placebo-treated controls. These findings of favorable PK profiles, tolerability, early rises in HbF, and total Hgb indicate that trials of longer duration appear warranted to more definitively evaluate the therapeutic potential of HQK-1001 in sickle cell disease.
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Affiliation(s)
- Abdullah Kutlar
- Department of Medicine, Sickle Cell Center, Medical College of Georgia, Augusta, GA, USA
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A reduced curcuminoid analog as a novel inducer of fetal hemoglobin. Ann Hematol 2012; 92:379-86. [PMID: 23079892 DOI: 10.1007/s00277-012-1604-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Accepted: 10/07/2012] [Indexed: 02/06/2023]
Abstract
Thalassemia is an inherited disorder of hemoglobin molecules that is characterized by an imbalance of α- and β-globin chain synthesis. Accumulation of unbound α-globin chains in erythroid cells is the major cause of pathology in β-thalassemia. Stimulation of γ-globin production can ameliorate disease severity as it combines with the α-globin to form fetal hemoglobin. We examined γ-globin-inducing effect of curcuminoids extracted from Curcuma longa L. and their metabolite reduced forms in erythroid leukemia K562 and human primary erythroid precursor cells. The results showed that curcuminoid compounds, especially bisdemethoxycurcumin are potential γ-globin enhancers. We also demonstrated that its reduced analog, hexahydrobisdemethoxycurcumin (HHBDMC), is most effective and leads to induction of γ-globin mRNA and HbF in primary erythroid precursor cells for 3.6 ± 0.4- and 2.0 ± 0.4-folds, respectively. This suggested that HHBDMC is the potential agent to be developed as a new therapeutic drug for β-thalassemia and related β-hemoglobinopathies.
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Regulation of delta-aminolevulinic acid dehydratase by krüppel-like factor 1. PLoS One 2012; 7:e46482. [PMID: 23056320 PMCID: PMC3463598 DOI: 10.1371/journal.pone.0046482] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Accepted: 08/31/2012] [Indexed: 12/18/2022] Open
Abstract
Krüppel-like factor 1(KLF1) is a hematopoietic-specific zinc finger transcription factor essential for erythroid gene expression. In concert with the transacting factor GATA1, KLF1 modulates the coordinate expression of the genes encoding the multi-enzyme heme biosynthetic pathway during erythroid differentiation. To explore the mechanisms underpinning KLF1 action at the gene loci regulating the first 3 steps in this process, we have exploited the K1-ERp erythroid cell line, in which KLF1 translocates rapidly to the nucleus in response to treatment with 4-OH-Tamoxifen (4-OHT). KLF1 acts as a differentiation-independent transcriptional co-regulator of delta-aminolevulinic acid dehydratase (Alad), but not 5-aminolevulinate synthase gene (Alas2) or porphobilinogen deaminase (Pbgd). Similar to its role at the β-globin promoter, KLF1 induces factor recruitment and chromatin changes at the Alad1b promoter in a temporally-specific manner. In contrast to these changes, we observed a distinct mechanism of histone eviction at the Alad1b promoter. Furthermore, KLF1-dependent events were not modulated by GATA1 factor promoter co-occupancy alone. These results not only enhance our understanding of erythroid-specific modulation of heme biosynthetic regulation by KLF1, but provide a model that will facilitate the elucidation of novel KLF1-dependent events at erythroid gene loci that are independent of GATA1 activity.
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Yien YY, Bieker JJ. Functional interactions between erythroid Krüppel-like factor (EKLF/KLF1) and protein phosphatase PPM1B/PP2Cβ. J Biol Chem 2012; 287:15193-204. [PMID: 22393050 DOI: 10.1074/jbc.m112.350496] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Erythroid Krüppel-like factor (EKLF; KLF1) is an erythroid-specific transcription factor required for the transcription of genes that regulate erythropoiesis. In this paper, we describe the identification of a novel EKLF interactor, Ppm1b, a serine-threonine protein phosphatase that has been implicated in the attenuation of NFκB signaling and the regulation of Cdk9 phosphorylation status. We show that Ppm1b interacts with EKLF via its PEST1 sequence. However, its genetic regulatory role is complex. Using a promoter-reporter assay in an erythroid cell line, we show that Ppm1b superactivates EKLF at the β-globin and BKLF promoters, dependent on intact Ppm1b phosphatase activity. Conversely, depletion of Ppm1b in CD34(+) cells leads to a higher level of endogenous β-globin gene activation after differentiation. We also observe that Ppm1b likely has an indirect role in regulating EKLF turnover via its zinc finger domain. Together, these studies show that Ppm1b plays a multilayered role in regulating the availability and optimal activity of the EKLF protein in erythroid cells.
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Affiliation(s)
- Yvette Y Yien
- Department of Developmental and Regenerative Biology, The Mount Sinai School of Medicine, New York, New York 10029, USA
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Boosalis MS, Castaneda SA, Trudel M, Mabaera R, White GL, Lowrey CH, Emery DW, Mpollo MSEM, Shen L, Wargin WA, Bohacek R, Faller DV, Perrine SP. Novel therapeutic candidates, identified by molecular modeling, induce γ-globin gene expression in vivo. Blood Cells Mol Dis 2012; 47:107-16. [PMID: 21641240 DOI: 10.1016/j.bcmd.2011.04.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Revised: 04/14/2011] [Accepted: 04/15/2011] [Indexed: 11/25/2022]
Abstract
The β-hemoglobinopathies and thalassemias are serious genetic blood disorders affecting the β-globin chain of hemoglobin A (α(2)β(Α)(2)). Their clinical severity can be reduced by enhancing expression of fetal hemoglobin (γ-globin), producing HbF (α(2)γ(2,)). In studies reported here, γ-globin induction by 23 novel, structurally-unrelated compounds, which had been predicted through molecular modeling and in silico screening of a 13,000 chemical library, was evaluated in vitro in erythroid progenitors cultured from normal subjects and β-thalassemia patients, and in vivo in transgenic mice or anemic baboons. Four predicted candidates were found to have high potency, with 4- to 8-fold induction of HbF. Two of these compounds have pharmacokinetic profiles favorable for clinical application. These studies thus effectively identified high potency γ-globin inducing candidate therapeutics and validated the utility of in silico molecular modeling.
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Affiliation(s)
- Michael S Boosalis
- Cancer Center and Hemoglobinopathy-Thalassemia Research Unit, Boston University School of Medicine, USA
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Abstract
The cellular events that lead to terminal erythroid differentiation rely on the controlled interplay of extra- and intracellular regulatory factors. Their downstream effects are highly coordinated and result in the structural/morphologic and metabolic changes that uniquely characterize a maturing red blood cell. Erythroid Krüppel-like factor (EKLF/KLF1) is one of a very small number of intrinsic transcription factors that play a major role in regulating these events. This review covers 3 major aspects of erythropoiesis in which EKLF plays crucial functions: (1) at the megakaryocyte-erythroid progenitor stage, where it is involved in erythroid lineage commitment; (2) during the global expansion of erythroid gene expression in primitive and definitive lineages, where it plays a direct role in globin switching; and (3) during the terminal maturation of red cells, where it helps control exit from the cell cycle. We conclude by describing recent studies of mammalian EKLF/KLF1 mutations that lead to altered red cell phenotypes and disease.
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Affiliation(s)
- Miroslawa Siatecka
- Department of Developmental and Regenerative Biology, Mount Sinai School of Medicine, New York, NY, USA
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Fyrberg A, Peterson C, Kågedal B, Lotfi K. Induction of fetal hemoglobin and ABCB1 gene expression in 9-β-D-arabinofuranosylguanine-resistant MOLT-4 cells. Cancer Chemother Pharmacol 2010; 68:583-91. [PMID: 21110023 DOI: 10.1007/s00280-010-1524-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2010] [Accepted: 11/05/2010] [Indexed: 10/18/2022]
Abstract
PURPOSE To characterize resistance mechanisms to the nucleoside analog 9-β-D-arabinofuranosylguanine (AraG) in the T-cell acute lymphoblastic leukemia cell line MOLT-4 and its AraG-resistant variant. METHODS A gene expression microarray analysis was performed, as well as gene expression and enzyme activity measurements of key enzymes in the activation of AraG. Cytotoxicity of AraG and cross-resistance to other compounds were evaluated using a standard cytotoxicity assay. RESULTS Gene expression microarray analysis revealed that fetal hemoglobin genes and the multidrug resistance ABCB1 gene, encoding the drug efflux pump P-gp, were the most highly upregulated genes in the resistant cells, while genes traditionally associated with nucleoside analog resistance were not. Fetal hemoglobin and ABCB1 induction can be due to global DNA hypomethylation. This phenomenon was studied using AraG during a period of 4 weeks in MOLT-4 cells and the lung adenocarcinoma cell line A549, leading to up-regulation of hemoglobin gamma and ABCB1 as well as DNA hypomethylation. Inhibiting P-gp in the AraG-resistant MOLT-4 cells led to decreased proliferation, reduced hemoglobin expression, and highly induced ABCB1 expression. CONCLUSIONS We show that AraG can cause hypomethylation of DNA and induce the expression of the fetal hemoglobin gamma gene and the ABCB1 gene. We speculate that the induction of ABCB1/P-gp may occur in order to help with excretion of hemoglobin degradation products that would otherwise be toxic to the cells, and we present data supporting our theory that P-gp may be linked to the induction of hemoglobin.
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Affiliation(s)
- Anna Fyrberg
- Department of Medicine and Health, Linköping University, Linköping, Sweden.
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Perrine SP, Castaneda SA, Chui DHK, Faller DV, Berenson RJ, Siritanaratku N, Fucharoen S. Fetal globin gene inducers: novel agents and new potential. Ann N Y Acad Sci 2010; 1202:158-64. [PMID: 20712788 PMCID: PMC3913055 DOI: 10.1111/j.1749-6632.2010.05593.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Inducing expression of endogenous fetal globin (gamma-globin) gene expression to 60-70% of alpha globin synthesis produces beta-thalassemia trait globin synthetic ratios and can reduce anemia to a mild level. Several classes of therapeutics have induced gamma-globin expression in beta-thalassemia patients and subsequently raised total hemoglobin levels, demonstrating proof-of-concept of the approach. Butyrate treatment eliminated transfusion requirements in formerly transfusion-dependent patients with treatment for as long as seven years. However, prior generation inducers were not readily applicable for widespread use. Currently, a novel oral dual-action therapeutic, sodium 2,2-dimethylbutyrate, is in clinical trials, an oral decitabine formulation is under development, and agents with complementary mechanisms of action can be applied in combined regimens. Identification of three major genetic trait loci which modulate clinical severity provides avenues for developing tailored regimens. These refinements offer renewed potential to apply fetal globin induction as a treatment approach in patient-friendly regimens that can be used worldwide.
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Affiliation(s)
- Susan P Perrine
- Cancer Center and Hemoglobinopathy-Thalassemia Research Unit, Department of Medicine, Pediatrics, Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, Massachusetts, USA.
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