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Yasara N, Premawardhena A, Mettananda S. A comprehensive review of hydroxyurea for β-haemoglobinopathies: the role revisited during COVID-19 pandemic. Orphanet J Rare Dis 2021; 16:114. [PMID: 33648529 PMCID: PMC7919989 DOI: 10.1186/s13023-021-01757-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 02/18/2021] [Indexed: 02/07/2023] Open
Abstract
Background Hydroxyurea is one of the earliest drugs that showed promise in the management of haemoglobinopathies that include β-thalassaemia and sickle cell disease. Despite this, many aspects of hydroxyurea are either unknown or understudied; specifically, its usefulness in β-thalassaemia major and haemoglobin E β-thalassaemia is unclear. However, during COVID-19 pandemic, it has become a valuable adjunct to transfusion therapy in patients with β-haemoglobinopathies. In this review, we aim to explore the available in vitro and in vivo mechanistic data and the clinical utility of hydroxyurea in β-haemoglobinopathies with a special emphasis on its usefulness during the COVID-19 pandemic. Main body Hydroxyurea is an S-phase-specific drug that reversibly inhibits ribonucleoside diphosphate reductase enzyme which catalyses an essential step in the DNA biosynthesis. In human erythroid cells, it induces the expression of γ-globin, a fetal globin gene that is suppressed after birth. Through several molecular pathways described in this review, hydroxyurea exerts many favourable effects on the haemoglobin content, red blood cell indices, ineffective erythropoiesis, and blood rheology in patients with β-haemoglobinopathies. Currently, it is recommended for sickle cell disease and non-transfusion dependent β-thalassaemia. A number of clinical trials are ongoing to evaluate its usefulness in transfusion dependent β-thalassaemia. During the COVID-19 pandemic, it was widely used as an adjunct to transfusion therapy due to limitations in the availability of blood and logistical disturbances. Thus, it has become clear that hydroxyurea could play a remarkable role in reducing transfusion requirements of patients with haemoglobinopathies, especially when donor blood is a limited resource. Conclusion Hydroxyurea is a well-tolerated oral drug which has been in use for many decades. Through its actions of reversible inhibition of ribonucleoside diphosphate reductase enzyme and fetal haemoglobin induction, it exerts many favourable effects on patients with β-haemoglobinopathies. It is currently approved for the treatment of sickle cell disease and non-transfusion dependent β-thalassaemia. Also, there are various observations to suggest that hydroxyurea is an important adjunct in the treatment of transfusion dependent β-thalassaemia which should be confirmed by randomised clinical trials.
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Affiliation(s)
- Nirmani Yasara
- Department of Paediatrics, Faculty of Medicine, University of Kelaniya, Thalagolla Road, Ragama, 11010, Sri Lanka
| | - Anuja Premawardhena
- Department of Medicine, Faculty of Medicine, University of Kelaniya, Ragama, Sri Lanka.,Colombo North Teaching Hospital, Ragama, Sri Lanka
| | - Sachith Mettananda
- Department of Paediatrics, Faculty of Medicine, University of Kelaniya, Thalagolla Road, Ragama, 11010, Sri Lanka. .,Colombo North Teaching Hospital, Ragama, Sri Lanka.
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Khan F, Ali A, Iqbal A, Musharraf SG. Profiling of hydroxyurea-treated β-thalassemia/ serum proteome through nano-LC-ESI-MS/ MS in combination with microsol-isoelectric focusing. Biomed Chromatogr 2019; 34:e4753. [PMID: 31777090 DOI: 10.1002/bmc.4753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 09/30/2019] [Accepted: 11/08/2019] [Indexed: 11/09/2022]
Abstract
Advancements in proteomic tools offer a comprehensive solution to studying the complexity of diseases at molecular level. This study focusses on the clinical proteomic profiling of pre- and post-hydroxyurea (HU)-treated β-thalassemia patients in parallel with healthy individuals to better understand the role of HU in the treatment of β-thalassemia. The strategy encompasses sequential high-resolution protein fractionation using MicroSol-isoelectric focusing (ZOOM- IEF) followed by one-dimensional SDS-PAGE before nano-RP-LC-MS/ MS analysis of tryptic peptides. Protein identification was performed through Mascot search using NCBInr and SwissProt databases. Several different proteins were observed in pool serum samples of each of the three study groups. Approximately, 1250 proteins exclusive to each group were identified, and after removing the redundant and low sequence coverage proteins, the number was reduced to 576 (201 in healthy, 187 in HU-untreated and 188 in HU-treated group). Uniquely identified proteins in the HU-treated group regulate the focal adhesion, ECM-receptor interaction, PI3K-Akt signaling, Rap1 signaling, cAMP signaling, platelet activation, and Ca2+ signaling pathways in the HU-treated group. The proteomic profile presented here will add to the current state of understanding of molecular mechanisms involved in hydroxyurea treatment of β-thalassemia.
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Affiliation(s)
- Faisal Khan
- Dr Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, Pakistan
| | - Arslan Ali
- Dr Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, Pakistan
| | - Ayesha Iqbal
- Dr Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, Pakistan
| | - Syed Ghulam Musharraf
- Dr Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, Pakistan.,H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, Pakistan
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Zohaib M, Ansari SH, Shamsi TS, Zubarev RA, Zarina S. Pharmacoproteomics Profiling of Plasma From β-Thalassemia Patients in Response to Hydroxyurea Treatment. J Clin Pharmacol 2018; 59:98-106. [PMID: 30152032 DOI: 10.1002/jcph.1297] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 07/11/2018] [Indexed: 11/07/2022]
Abstract
β-Thalassemia is a genetic disorder caused by defects in the β-globin gene resulting in the absence or reduced synthesis of adult hemoglobin (HbA). Hydroxyurea is an effective drug to increase fetal γ-globin (HbF) expression, replacing the missing adult β-globin. The mechanism of HbF induction by hydroxyurea and improvement in clinical symptoms are still poorly understood. In the present study we performed comparative analysis of plasma proteome in pre- and post-hydroxyurea-treated β-thalassemia major transfusion-dependent children (n = 10, mean age = 3.2 years) as well as responders versus nonresponders to hydroxyurea treatment. Plasma was collected before and after 6 months of hydroxyurea treatment, with patients subcategorized on the basis of their response to hydroxyurea. Among 400 identified proteins using a label-free quantitative proteomics approach, 28 proteins were found to be significantly different in pre- versus post-hydroxyurea-treated groups, with transferrin receptor protein-1 being most downregulated and hemopexin and haptoglobin the most upregulated proteins after treatment. In responder versus nonresponder comparison, 26 proteins were found to be differentially expressed, with carbonic anhydrase 1, hemoglobin subunit γ-1, and peroxiredoxin-2 showing the significant changes. The mechanism of hydroxyurea treatment in β-thalassemia patients appears to be complex, requiring a large sample size and a longer period of treatment to reveal its details.
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Affiliation(s)
- Muhammad Zohaib
- National Center for Proteomics, University of Karachi, Karachi, Pakistan
| | - Saqib H Ansari
- National Institute of Blood Diseases and Bone Marrow Transplantation, Karachi, Pakistan
| | - Tahir S Shamsi
- National Institute of Blood Diseases and Bone Marrow Transplantation, Karachi, Pakistan
| | - Roman A Zubarev
- Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.,Department of Pharmacological & Technological Chemistry, I.M. Sechenov First Moscow State Medical University, Moscow, Russia
| | - Shamshad Zarina
- National Center for Proteomics, University of Karachi, Karachi, Pakistan
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4
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Minniti CP, Kato GJ. Critical Reviews: How we treat sickle cell patients with leg ulcers. Am J Hematol 2016; 91:22-30. [PMID: 26257201 DOI: 10.1002/ajh.24134] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 07/23/2015] [Indexed: 12/22/2022]
Abstract
The past five decades have seen an improvement in the mortality and morbidity of sickle cell disease (SCD) because of prophylaxis against infectious complications, improved and expanded red cell transfusions, implementation of hydroxyurea therapy, and advances in supportive care. Now that the majority of patients in the western hemisphere reaches adulthood, end organ diseases are frequent, which include vasculopathic complications such as chronic leg ulcers. The management of patients with leg ulcers requires the hematologist to lead a team of health care professionals, and investigates the presence of associated, but potentially still occult signs of vasculopathy, such as pulmonary hypertension, renal disease, priapism and retinopathy. These complications may be asynchronous, and long term careful screening is indicated, in order to ensure early diagnosis and intervention. It is crucial to address both the immediate consequences of pain, infection and disability, and long term effects on quality of life, employment and stigma associated with chronic ulceration. Recent insights into their pathophysiology may have practical implications. We propose a holistic approach to the management of patients' physical and emotional problems and mechanisms of ulcers formation and delayed healing. An overview of topical and systemic therapies for chronic ulcers is given, with the understanding that wound care therapy is best left to the wound specialists, medical and surgical, with whom the hematologist must keep an open line of communication. In the absence of evidence-based guidelines, our opinion is based on both a critical review of the literature and our personal clinical and research experience.
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Affiliation(s)
- Caterina P. Minniti
- Division of Hematology-Oncology, Department of Medicine; Montefiore Medical Center; Bronx New York
| | - Gregory J. Kato
- Division of Hematology-Oncology, Department of Medicine and the Heart, Lung; Blood and Vascular Medicine Institute, University of Pittsburgh; Pittsburgh Pennsylvania
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5
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Lebensburger JD, Patel RJ, Palabindela P, Bemrich-Stolz CJ, Howard TH, Hilliard LM. Hydroxyurea decreases hospitalizations in pediatric patients with Hb SC and Hb SB+ thalassemia. J Blood Med 2015; 6:285-90. [PMID: 26719735 PMCID: PMC4687721 DOI: 10.2147/jbm.s97405] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PURPOSE Patients with hemoglobin SC (Hb SC) and hemoglobin SB+ (Hb SB+) thalassemia suffer from frequent hospitalizations yet strong evidence of a clinical benefit of hydroxyurea (HU) in this population is lacking. Patients with recurrent hospitalizations for pain crisis are offered HU at our institution based on small cohort data and anecdotal benefit. This study identifies outcomes from a large cohort of patients with Hb SC and SB+ thalassemia who were treated with HU for 2 years. MATERIALS AND METHODS A retrospective review was conducted of 32 patients with Hb SC and SB+ thalassemia who were treated with HU. We reviewed the number, and reasons for hospitalization in the 2 years prior to, and 2 years post-HU treatment as well as laboratory changes from baseline, over 1 year. RESULTS Patients with Hb SC and SB+ thalassemia started on HU for frequent pain, had a significant reduction in hospitalizations over 2 years as compared to the 2 years prior to HU initiation (mean total hospitalizations/year: pre-HU: 1.6 vs post-HU 0.4 hospitalizations, P<0.001; mean pain hospitalizations/year: pre-HU 1.5 vs post-HU 0.3 hospitalizations, P<0.001). Patients demonstrated hematologic changes including an increase in percent fetal hemoglobin (%HbF) pre-post HU (4.5% to 7.7%, P=0.002), mean corpuscular volume (74 to 86 fL, P<0,0001), and decrease in absolute neutrophil count (5.0 to 3.2×10(9)/L, P=0.007). Patients with higher doses of HU demonstrated the greatest reduction in hospitalizations but this was unrelated to absolute neutrophil count. CONCLUSION This cohort of patients with Hb SC and SB+ thalassemia provides additional support for using HU in patients with recurrent hospitalizations for pain. A large randomized multicenter trial of HU to reduce pain admissions should be conducted to confirm these data and provide much needed evidence based recommendations for this population.
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Affiliation(s)
- Jeffrey D Lebensburger
- Division of Pediatric Hematology Oncology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Rakeshkumar J Patel
- Division of Pediatric Hematology Oncology, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | | | - Thomas H Howard
- Division of Pediatric Hematology Oncology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Lee M Hilliard
- Division of Pediatric Hematology Oncology, University of Alabama at Birmingham, Birmingham, AL, USA
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Abstract
Major hemoglobinopathies, including sickle cell anemia, are becoming a global health issue. Leg ulcers are the most common cutaneous manifestation of sickle cell disease and an important contributor to morbidity burden in this population. Leg ulcers following sickling disorders are extremely painful, and hard to heal. The clinical evidence for the optimal management of these ulcers is limited. Treating the cause and the strategies to prevent sickling are the mainstay of treatment. The basic principles of wound bed preparation and compression therapy is beneficial in these patients.
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Shome DK, Al Ajmi A, Radhi AA, Mansoor EJ, Majed KS. The Effect of Hydroxyurea Therapy in Bahraini Sickle Cell Disease Patients. Indian J Hematol Blood Transfus 2015; 32:104-9. [PMID: 26855516 DOI: 10.1007/s12288-015-0529-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2014] [Accepted: 03/09/2015] [Indexed: 10/23/2022] Open
Abstract
Hydroxyurea (HU) is used as a disease-modifying agent in sickle cell disease (SCD). Its beneficial effects have been ascribed to inhibition of the sickling process through increase of fetal hemoglobin (HbF) levels and influence on multiple factors affecting adhesion of erythrocytes to vascular endothelium. The present study investigates the effect of HU in SCD patients who were grouped on the basis of association with α- and β-thalassemia using routine laboratory methods. A retrospective cross-sectional chart-review was done of 51 adult Bahraini SCD patients attending Salmaniya Medical Complex, Bahrain. Four sub-groups of cases were identified: (i) homozygous sickle cell anemia, 24 cases; (ii) SCD with microcytosis, 16 cases; (iii) sickle α-thalassemia, seven cases; and (iv) sickle β thalassemia, four cases. Documented laboratory and clinical data included hemoglobin level (Hb), hematocrit (Hct), red cell indices, hemoglobin fractions, hospital admissions (frequency), number of inpatient-days, pain episodes (frequency) and red cell transfusion requirement (number of units). Pre- and post-treatment data were compared. Hydroxyurea treatment led to highly significant reduction of HbS % and pain crisis episodes in all patient groups. Other changes such as increases of total hemoglobin, Hct and HbF and reduction of hospital admissions, inpatient days and red cell units transfused also occurred but with less consistent levels of significance within patient sub-groups. Treatment with HU is beneficial for all subgroups of Bahraini SCD patients, without or with α- and β-thalassemia interactions.
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Affiliation(s)
- Durjoy K Shome
- Department of Pathology, College of Medicine and Medical Sciences, Arabian Gulf University, P.O. Box 26671, Manama, Kingdom of Bahrain ; Department of Pathology, Salmaniya Medical Complex, P.O. Box 12, Manama, Kingdom of Bahrain
| | - Abdulla Al Ajmi
- Department of Hematology and Oncology, Salmaniya Medical Complex, P.O. Box 12, Manama, Kingdom of Bahrain
| | - Ameera A Radhi
- Department of Pathology, Salmaniya Medical Complex, P.O. Box 12, Manama, Kingdom of Bahrain
| | - Eman J Mansoor
- Department of Pathology, Salmaniya Medical Complex, P.O. Box 12, Manama, Kingdom of Bahrain
| | - Kameela S Majed
- Department of Pathology, Salmaniya Medical Complex, P.O. Box 12, Manama, Kingdom of Bahrain
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8
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Bayanzay K, Khan R. Meta-analysis on effectiveness of hydroxyurea to treat transfusion-dependent beta-thalassemia. ACTA ACUST UNITED AC 2014; 20:469-476. [PMID: 25535888 DOI: 10.1179/1607845414y.0000000222] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Objective To determine the efficacy of hydroxyurea therapy on transfusion-dependent beta-thalassemia patients. Methods This study collected articles from databases, applied inclusion and exclusion criteria, and analyzed them for bias. The effects of hydroxyurea on transfusion requirements were categorized according to the following definitions. 'Good responders' were participants who became transfusion independent after treatment. 'Moderate responders' were participants who were still transfusion dependent, however, experienced a significant decline in their transfusion requirements. 'Poor responders' were defined as participants who did not respond to hydroxyurea. Results A total of 13 studies met all the inclusion and exclusion criteria providing a total of 1196 study participants. The weighted average of the odds ratio using the random effect model (P < 0.001) was determined to be 0.493 for good responders, 0.270 for moderate responders, and 0.229 for poor responders. Discussion Until now, there has not been any double-blinded placebo-controlled studies performed looking at the effectiveness of hydroxyurea with this regard, and this substantially limits this meta-analysis. More studies should be conducted to determine whether hydroxyurea preferentially treats particular type of mutations over others. Conclusion This study suggests that hydroxyurea provides some benefit to patients, and therefore, in certain clinical situations, it may be understandable to start a trial therapy of hydroxyurea to qualifying patients. However, a double-blinded placebo-controlled studies should be performed before its efficacy can be considered established.
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Affiliation(s)
| | - Ramsha Khan
- b Gulf Medical University , Ajman, United Arab Emirates
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9
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Kosaryan M, Zafari M, Alipur A, Hedayatizadeh-Omran A. The Effect and Side Effect of Hydroxyurea Therapy on Patients With β-Thalassemia: A Systematic Review to December 2012. Hemoglobin 2014; 38:262-71. [DOI: 10.3109/03630269.2014.927770] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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10
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Sobush KT, Thornburg CD, Voynow JA, Davis SD, Peterson-Carmichael SL. A 2-year-old girl with co-inherited cystic fibrosis and sickle cell-β+ thalassemia presenting with recurrent vaso-occlusive events during cystic fibrosis pulmonary exacerbations: a case report. J Med Case Rep 2013; 7:203. [PMID: 23890029 PMCID: PMC3750320 DOI: 10.1186/1752-1947-7-203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Accepted: 05/31/2013] [Indexed: 12/17/2023] Open
Abstract
Introduction This is the first published report of a young girl with co-inherited sickle cell-β+ thalassemia and cystic fibrosis. Although a small subset of patients with co-inherited cystic fibrosis and other hemoglobinopathies have been reported, this patient developed early hematologic and pulmonary complications that were more severe than the previous cases. To assess pulmonary co-morbidities, we used infant pulmonary function testing through the raised volume rapid thoracoabdominal compression technique as both an established study of early cystic fibrosis and also as a newer study of mechanism for early sickle cell lung disease. This further serves as the first report of the raised volume rapid thoracoabdominal compression technique to determine raised volume forced expiratory flows and fractional lung volumes in a patient with a hemoglobinopathy. Case presentation A 2-year-old African-American girl with co-inherited cystic fibrosis and sickle cell-β+ thalassemia developed severe hematologic complications (recurrent vaso-occlusive events, hepatic sequestration, and acute chest syndrome) during periods of cystic fibrosis pulmonary exacerbations and weight loss. Because cystic fibrosis and sickle cell-β+ thalassemia both confer distinct patterns of pulmonary disease, infant pulmonary function testing with the raised volume rapid thoracoabdominal compression technique was used to define respiratory pathophysiology and guide treatment options. Infant pulmonary function testing data demonstrated moderate-to-severe lower airways obstruction, moderate air trapping, and no evidence of restrictive lung disease. Conclusions Infant pulmonary function testing with the raised volume rapid thoracoabdominal compression technique guided therapy in this patient with cystic fibrosis and sickle cell-β+ thalassemia. Although this is an original case report on a unique patient, this case highlights the need to evaluate early respiratory pathophysiology in a broader population of young patients with hemoglobinopathies and screen those at risk for early pulmonary co-morbidities.
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Affiliation(s)
- Kurtis T Sobush
- Division of Pediatric Pulmonary and Sleep Medicine, Duke University Medical Center, Durham, North Carolina, USA.
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Yates AM, Dedeken L, Smeltzer MP, Lebensburger JD, Wang WC, Robitaille N. Hydroxyurea treatment of children with hemoglobin SC disease. Pediatr Blood Cancer 2013; 60:323-5. [PMID: 22949140 DOI: 10.1002/pbc.24283] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 07/16/2012] [Indexed: 11/12/2022]
Abstract
The efficacy of hydroxyurea in hemoglobin SC (HbSC) patients is not well documented. We describe the long-term response to hydroxyurea in children with clinically severe HbSC. In 15 patients, hydroxyurea resulted in a significant increase in mean corpuscular volume (MCV) and fetal hemoglobin (HbF) and a significant decrease in episodes of acute chest syndrome and hospitalization for pain; there was no effect on hemoglobin level. The most significant side effect was thrombocytopenia, which led to discontinuation of treatment in one patient. This study suggests that hydroxyurea has efficacy and is safe for long-term therapy in patients with HbSC.
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Affiliation(s)
- Amber M Yates
- Baylor College of Medicine and Texas Children's Hematology Center, Houston, Texas, USA.
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12
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Clinical experience with fetal hemoglobin induction therapy in patients with β-thalassemia. Blood 2013; 121:2199-212; quiz 2372. [PMID: 23315167 DOI: 10.1182/blood-2012-10-408021] [Citation(s) in RCA: 133] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Recent molecular studies of fetal hemoglobin (HbF) regulation have reinvigorated the field and shown promise for the development of clinical HbF inducers to be used in patients with β-thalassemia and sickle cell disease. However, while numerous promising inducers of HbF have been studied in the past in β-thalassemia patient populations, with limited success in some cases, no universally effective agents have been found. Here we examine the clinical studies of such inducers in an attempt to systematically review the field. We examine trials of agents, including 5-azacytidine, hydroxyurea, and short-chain fatty acids. This review highlights the heterogeneity of clinical studies done on these agents, including both the patient populations examined and the study end points. By examining the published studies of these agents, we hope to provide a resource that will be valuable for the design of future studies of HbF inducers in β-thalassemia patient populations.
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13
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Experience with the use of vacuum-assisted closure therapy in the management of sickle cell leg ulcers. EUROPEAN JOURNAL OF PLASTIC SURGERY 2012. [DOI: 10.1007/s00238-011-0632-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Neves F, Menezes Neto OA, Polis LB, Bassi SC, Brunetta DM, Silva-Pinto AC, Angulo IL. Hematological differences between patients with different subtypes of sickle cell disease on hydroxyurea treatment. Rev Bras Hematol Hemoter 2012; 34:426-9. [PMID: 23323066 PMCID: PMC3545429 DOI: 10.5581/1516-8484.20120107] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2012] [Accepted: 07/31/2012] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE Sickle cell anemia and the interaction S/Beta thalassemia differ in hematological values due to microcytosis and hypochromia caused by the thalassemic mutation. The clinical benefit of long-term hydroxyurea treatment is undeniable in sickle cell disease with monitoring of the biological action of the drug being by the complete blood count. The objective of this work is to compare changes in some of the erythrocytic indexes between S/Beta thalassemia and sickle cell anemia patients on long-term hydroxyurea treatment. METHODS The values of erythrocyte indexes (mean corpuscular volume and mean corpuscular hemoglobin) were compared in a retrospective study of two groups of patients (Sickle cell anemia and S/Beta thalassemia) on hydroxyurea treatment over a mean of six years. RESULTS The quantitative values of the two parameters differed between the groups. Increases in mean corpuscular volume and reductions in mean corpuscular hemoglobin delay longer in S/Beta thalassemia patients (p-value = 0.018). CONCLUSION Hematological changes are some of the beneficial effects of hydroxyurea in sickle cell disease as cellular hydration increases and the hemoglobin S concentration is reduced. The complete blood count is the best test to monitor changes, but the interpretation of the results in S/Beta thalassemia should be different.
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Affiliation(s)
- Fabia Neves
- Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto,
Universidade de São Paulo - USP, Ribeirão Preto, SP, Brazil
| | - Osvaldo Alves Menezes Neto
- Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto,
Universidade de São Paulo - USP, Ribeirão Preto, SP, Brazil
| | - Larissa Bueno Polis
- Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto,
Universidade de São Paulo - USP, Ribeirão Preto, SP, Brazil
| | - Sarah Cristina Bassi
- Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto,
Universidade de São Paulo - USP, Ribeirão Preto, SP, Brazil
| | - Denise Menezes Brunetta
- Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto,
Universidade de São Paulo - USP, Ribeirão Preto, SP, Brazil
| | - Ana Cristina Silva-Pinto
- Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto,
Universidade de São Paulo - USP, Ribeirão Preto, SP, Brazil
| | - Ivan Lucena Angulo
- Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto,
Universidade de São Paulo - USP, Ribeirão Preto, SP, Brazil
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15
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The effect of prolonged administration of hydroxyurea on morbidity and mortality in adult patients with sickle cell syndromes: results of a 17-year, single-center trial (LaSHS). Blood 2009; 115:2354-63. [PMID: 19903897 DOI: 10.1182/blood-2009-05-221333] [Citation(s) in RCA: 296] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The aim of this prospective study was to evaluate the long-term efficacy and safety of hydroxyurea (HU) in patients with sickle cell disease (SCD). Thirty-four patients with sickle cell anemia (hemoglobin S [HbS]/HbS), 131 with HbS/beta(0)-thal, and 165 with HbS/beta(+)-thal participated in this trial. HU was administered to 131 patients, whereas 199 patients were conventionally treated. The median follow-up period was 8 years for HU patients and 5 years for non-HU patients. HU produced a dramatic reduction in the frequency of severe painful crises, transfusion requirements, hospital admissions, and incidence of acute chest syndrome. The probability of 10-year survival was 86% and 65% for HU and non-HU patients, respectively (P = .001), although HU patients had more severe forms of SCD. The 10-year probability of survival for HbS/HbS, HbS/beta (0)-thal, and HbS/IVSI-110 patients was 100%, 87%, and 82%, respectively, for HU patients and 10%, 54%, and 66%, for non-HU patients. The multivariate analysis showed that fetal hemoglobin values at baseline and percentage change of lactate dehydrogenase between baseline and 6 months were independently predicted for survival in the HU group. These results highlight the beneficial effect of HU, which seems to modify the natural history of SCD and raise the issue of expanding its use in all SCD patients.
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16
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[Genetic causes of impaired wound healing. Rare differential diagnosis of the non-healing wound]. Hautarzt 2009; 59:893-903. [PMID: 18936901 DOI: 10.1007/s00105-008-1591-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Chronic leg ulcers affect about 1% of the German population. The intense search for the underlying cause of impaired wound healing is an essential requirement for successful therapy. The most common causes comprise chronic venous insufficiency (70%), peripheral arterial occlusive disease (10%) and diabetes mellitus. Besides vasculitis, infectious diseases and tumors, genetic diseases may constitute the underlying cause for impaired wound healing. In this review various rare genetic diseases causing chronic wounds like the Klinefelter-Syndrome, immunological diseases including the TAP-deficiency-syndrome and the leukocyte adhesion deficiency-syndromes, red blood cell disorders, thalassemia, thrombotic diseases, progeroid syndromes and inherited connective tissue disorders are presented.
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Abstract
BACKGROUND Hydroxyurea is the only approved drug for treatment of sickle cell disease. OBJECTIVE To synthesize the published literature on the efficacy, effectiveness, and toxicity of hydroxyurea when used in adults with sickle cell disease. DATA SOURCES MEDLINE, EMBASE, TOXLine, and CINAHL were searched through 30 June 2007. STUDY SELECTION Randomized trials, observational studies, and case reports evaluating efficacy and toxicity of hydroxyurea in adults with sickle cell disease, and toxicity studies of hydroxyurea in other conditions that were published in English. DATA EXTRACTION Paired reviewers abstracted data on study design, patient characteristics, and outcomes sequentially and did quality assessments independently. DATA SYNTHESIS In the single randomized trial, the hemoglobin level was higher in hydroxyurea recipients than placebo recipients after 2 years (difference, 6 g/L), as was fetal hemoglobin (absolute difference, 3.2%). The median number of painful crises was 44% lower than in the placebo group. The 12 observational studies that enrolled adults reported a relative increase in fetal hemoglobin of 4% to 20% and a relative reduction in crisis rates by 68% to 84%. Hospital admissions declined by 18% to 32%. The evidence suggests that hydroxyurea may impair spermatogenesis. Limited evidence indicates that hydroxyurea treatment in adults with sickle cell disease is not associated with leukemia. Likewise, limited evidence suggests that hydroxyurea and leg ulcers are not associated in patients with sickle cell disease, and evidence is insufficient to estimate the risk for skin neoplasms, although these outcomes can be attributed to hydroxyurea in other conditions. LIMITATION Only English-language articles were included, and some studies were of lower quality. CONCLUSION Hydroxyurea has demonstrated efficacy in adults with sickle cell disease. The paucity of long-term studies limits conclusions about toxicity.
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Lanzkron S, Strouse JJ, Wilson R, Beach MC, Haywood C, Park H, Witkop C, Bass EB, Segal JB. Systematic review: Hydroxyurea for the treatment of adults with sickle cell disease. Ann Intern Med 2008; 148:939-55. [PMID: 18458272 PMCID: PMC3256736 DOI: 10.7326/0003-4819-148-12-200806170-00221] [Citation(s) in RCA: 175] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Hydroxyurea is the only approved drug for treatment of sickle cell disease. OBJECTIVE To synthesize the published literature on the efficacy, effectiveness, and toxicity of hydroxyurea when used in adults with sickle cell disease. DATA SOURCES MEDLINE, EMBASE, TOXLine, and CINAHL were searched through 30 June 2007. STUDY SELECTION Randomized trials, observational studies, and case reports evaluating efficacy and toxicity of hydroxyurea in adults with sickle cell disease, and toxicity studies of hydroxyurea in other conditions that were published in English. DATA EXTRACTION Paired reviewers abstracted data on study design, patient characteristics, and outcomes sequentially and did quality assessments independently. DATA SYNTHESIS In the single randomized trial, the hemoglobin level was higher in hydroxyurea recipients than placebo recipients after 2 years (difference, 6 g/L), as was fetal hemoglobin (absolute difference, 3.2%). The median number of painful crises was 44% lower than in the placebo group. The 12 observational studies that enrolled adults reported a relative increase in fetal hemoglobin of 4% to 20% and a relative reduction in crisis rates by 68% to 84%. Hospital admissions declined by 18% to 32%. The evidence suggests that hydroxyurea may impair spermatogenesis. Limited evidence indicates that hydroxyurea treatment in adults with sickle cell disease is not associated with leukemia. Likewise, limited evidence suggests that hydroxyurea and leg ulcers are not associated in patients with sickle cell disease, and evidence is insufficient to estimate the risk for skin neoplasms, although these outcomes can be attributed to hydroxyurea in other conditions. LIMITATION Only English-language articles were included, and some studies were of lower quality. CONCLUSION Hydroxyurea has demonstrated efficacy in adults with sickle cell disease. The paucity of long-term studies limits conclusions about toxicity.
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Affiliation(s)
- Sophie Lanzkron
- School of Medicine ,Johns Hopkins University, 1830 East Monument Street, Suite 7300, Baltimore, MD 21205, USA
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Liebelt EL, Balk SJ, Faber W, Fisher JW, Hughes CL, Lanzkron SM, Lewis KM, Marchetti F, Mehendale HM, Rogers JM, Shad AT, Skalko RG, Stanek EJ. NTP-CERHR expert panel report on the reproductive and developmental toxicity of hydroxyurea. ACTA ACUST UNITED AC 2007; 80:259-366. [PMID: 17712860 DOI: 10.1002/bdrb.20123] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Masiello D, Heeney MM, Adewoye AH, Eung SH, Luo HY, Steinberg MH, Chui DHK. Hemoglobin SE disease: a concise review. Am J Hematol 2007; 82:643-9. [PMID: 17278112 DOI: 10.1002/ajh.20847] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
An infant with Hb SE disease is reported. He was clinically well. Review of the literature shows that patients aged 18 and younger are usually well. On the other hand, more than half of those aged 20 and older developed sickling-related complications, including potentially life-threatening acute chest syndrome. These patients have 60-65% Hb S, similar to the percent Hb S in patients with Hb S/beta(+)-thalassemia. Their hematological features and clinical course appear to parallel those of Hb S/beta(+)-thalassemia. Patients have variable levels of anemia, and some develop clinical complications. With population migrations and increasing racial intermarriages, Hb SE disease is expected to be encountered more often around the globe. Patients with Hb SE disease should be followed and managed in a similar fashion as those with Hb S/beta(+)-thalassemia, and treated appropriately when they develop sickling-related symptoms and complications.
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MESH Headings
- Adult
- Anemia, Hemolytic, Congenital/genetics
- Anemia, Hemolytic, Congenital/metabolism
- Anemia, Hemolytic, Congenital/pathology
- Anemia, Hemolytic, Congenital/therapy
- Child
- Female
- Hemoglobin E/genetics
- Hemoglobin E/metabolism
- Hemoglobin, Sickle/genetics
- Hemoglobin, Sickle/metabolism
- Humans
- Infant
- Infant, Newborn
- Male
- Mutation/genetics
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Affiliation(s)
- David Masiello
- The Center of Excellence in Sickle Cell Disease, Department of Medicine, School of Medicine, Boston University, Boston, MA, USA
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Serjeant GR, Serjeant BE, Mohan JS, Clare A. Leg Ulceration in Sickle Cell Disease: Medieval Medicine in a Modern World. Hematol Oncol Clin North Am 2005; 19:943-56, viii-ix. [PMID: 16214654 DOI: 10.1016/j.hoc.2005.08.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Leg ulceration is now recognized as an important complication of sickle cell disease, especially of the SS genotype. Since there is no convincing evidence of delayed healing of operation scars or of wounds elsewhere in the body, it must be concluded that factors specific to the lower leg render patients prone to delayed healing at this site. Many lesions are traumatic in origin and since there is considerable variation in healing rates among the normal population, it is useful to define chronic leg ulceration on the basis of a minimal duration, which in Jamaican studies has required at least 3 months and sometimes 6 months before healing. This minimal duration avoids the difficulties of interpreting the significance of briefer lesions since the moment of final healing may be poorly defined (patients may conclude that a scab represents healing whereas small lesions persist beneath) and often goes undocumented as patients may not report and medical attendants may not enquire, the date of final healing.
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Voskaridou E, Douskou M, Terpos E, Stamoulakatou A, Meletis J, Ourailidis A, Papassotiriou I, Loukopoulos D. Deferiprone as an oral iron chelator in sickle cell disease. Ann Hematol 2005; 84:434-40. [PMID: 15809885 DOI: 10.1007/s00277-005-1015-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2004] [Accepted: 01/26/2005] [Indexed: 01/13/2023]
Abstract
Iron overload is not uncommon in sickle cell disease (SCD) and requires regular chelation therapy in several instances. The present study evaluates the effect of deferiprone in 15 adult patients with SCD (ten beta(s)/beta(0)thalassemia and five beta(s)/beta(s)) and iron overload. Deferiprone was given at a dose of 75 mg/kg daily for 12 months. The evaluation considered pre- and post-treatment values of serum ferritin, urinary iron excretion, and T2 values of liver and heart obtained by magnetic resonance imaging (MRI). Eleven patients had a liver biopsy prior to starting therapy to evaluate iron concentration (LIC). Twelve patients completed the study with satisfactory compliance. In ten of them (83.3%) the serum ferritin levels decreased significantly at the end of the trial; in eight patients (66.6%) the reduction of serum ferritin was accompanied by a significant increase of their liver T2 values. All patients had a significant increase of urinary iron excretion in response to the drug. Ferritin levels and liver T2 values correlated with liver iron concentration; on the contrary, ferritin levels and liver T2 values failed to show any correlation with heart T2 values. Heart T2 values did not also show any correlation with left ventricular ejection fraction. Deferiprone was well tolerated and did not cause any significant adverse effects. These results suggest that deferiprone may effectively decrease the iron deposition in patients with SCD; moreover, T2 MRI proves to be a reliable and rapid, noninvasive method for assessing the liver iron load in patients with SCD.
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Affiliation(s)
- Ersi Voskaridou
- Thalassemia Center, Laikon General Hospital, 16 Sevastoupoleos Street, 11526, Athens, Greece.
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Affiliation(s)
- Jennifer T Trent
- Department of Dermatology and Cutaneous Surgery, University of Miami School of Medicine, Miami, FL, USA
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Tanyi RA. Sickle cell disease: health promotion and maintenance and the role of primary care nurse practitioners. ACTA ACUST UNITED AC 2003; 15:389-97. [PMID: 14560435 DOI: 10.1111/j.1745-7599.2003.tb00413.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE To discuss the role of nurse practitioners (NPs) with regard to early identification of affected individuals, effective monitoring and screening, effective pain management and prophylaxis, and health education for patients with sickle cell disease (SCD). DATA SOURCES Electronic database searches were performed using Medline, Cinahl, and PsycINFO. Data were obtained from medical textbooks, research, and review articles. CONCLUSIONS SCD is a chronic inherited disease belonging to a group of conditions called hemoglobinopathies. Individuals with SCD often require close medical care from specialists. Nonetheless, NPs are in ideal positions to facilitate the health promotion and health maintenance necessary to decrease the high rate of morbidity and mortality associated with this disease. IMPLICATIONS FOR PRACTICE NPs must understand the importance of early identification of affected individuals, effective monitoring and screening, effective monitoring and screening, effective pain treatment, and prophylaxis. The unpredictable trajectory of SCD can lead to frustration, fear, helplessness, hopelessness, and emotional distress. Ineffective pain management is a major problem for people with SCD. NPs can overcome this problem by initiating effective and prompt pain management in a nonjudgmental manner.
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Affiliation(s)
- Ruth A Tanyi
- Family Practice Department of the Allina Medical Clinic, Coon Rapids, Minnesota, USA.
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Abstract
Sickle hemoglobin (HbS), as a result of its polymer-related and oxidant effects, damages the sickle erythrocyte, provokes inflammation, and causes endothelial injury. All these elements cause the phenotype of sickle cell disease. Novel treatments inhibit HbS polymerization by inducing fetal hemoglobin expression, prevent or repair erythrocyte dehydration by slowing cellular potassium and water loss, and replace HbS-producing erythroid progenitors by stem cell transplantation. Future treatment prospects include gene therapy, interruption of the interaction of sickle cells with the endothelium, inhibition of oxidative damage, and protection of an injured endothelium.
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Affiliation(s)
- Martin H Steinberg
- Department of Medicine and Pediatrics, Boston University School of Medicine, 88 E Newton Street, Boston, Massachusetts 02118, USA.
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Abstract
Sickle cell disease (SCD) is one of the most common genetic diseases with some 250,000 new births each year. Most patients suffer intermittent pain crises and life-threatening events while life expectancy is considerably reduced. Until the last decade management was purely preventative or supportive aimed at symptom control. Apart from stem cell transplant, there is no cure but the oral chemotherapeutic drug hydroxyurea (HU) has now established a role in ameliorating the disease and improving life expectancy for most patients. There are side effects and risks of HU treatment in SCD but for moderate and severely affected patients, the benefits can be significant.
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Affiliation(s)
- Sally C Davies
- Imperial College Faculty of Medicine at Central Middlesex Hospital, Acton Lane, London NW10 7NS, UK.
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Skarpidi E, Cao H, Heltweg B, White BF, Marhenke RL, Jung M, Stamatoyannopoulos G. Hydroxamide derivatives of short-chain fatty acids are potent inducers of human fetal globin gene expression. Exp Hematol 2003; 31:197-203. [PMID: 12644016 DOI: 10.1016/s0301-472x(02)01030-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To examine whether hydroxamic acids are inducers of fetal hemoglobin expression, we tested the effects on gamma gene expression of butyric and propionic hydroxamic acids and of two other hydroxamic acids (SBHA and SAHA), which are potent inhibitors of histone deacetylase (HDAC). We also investigated whether there is a correlation between HDAC inhibitory activity of the compounds and their ability to induce gamma-globin gene expression. MATERIALS AND METHODS Effects on gamma-globin expression were assessed by two methods: 1) a screening assay in which specific gamma-globin gene inducers are recognized by their ability to increase gamma firefly luciferase activity significantly more than beta-renilla luciferase activity; and 2) measurements of gamma-globin mRNA and the frequency of fetal hemoglobin-positive erythroblasts in cultures of burst-forming unit erythroid (BFU-E) from normal individuals. HDAC in vitro activity was measured with a partially purified rat liver HDAC and a fluorogenic substrate. RESULTS All compounds tested increased gamma firefly luciferase activity, gamma/gamma+beta mRNA ratios, and percentage of fetal hemoglobin-containing erythroblasts in BFU-E cultures, in a dose-dependent fashion. Butyryl-hydroxamic acid 100 microM increased the gamma/gamma+beta mRNA ratios by 5.8-fold and the frequency of fetal hemoglobin-containing erythroblasts by 4.1-fold. Propionyl-hydroxamic acid 150 microM increased the gamma/gamma+beta ratios by 6.3-fold and the fetal hemoglobin-containing erythroblasts by 3.9-fold. SBHA induced gamma-globin gene expression at very low concentrations, 5 to 20 microM in the luciferase system and 2 to 8 microM in BFU-E cultures; SAHA at 1 to 7.5 microM in the luciferase system and 1 to 2.5 microM in the BFU-E cultures. HDAC in vitro inhibition was observed in the millimolar range for propionate and butyrate. IC(50) determinations led to values of 384 microM for propionyl-hydroxamate, 47 microM for butyryl-hydroxamate, 0.93 microM for SBHA, and 0.26 microM for SAHA. CONCLUCION: Our data indicate that hydroxamic acid-based HDAC inhibitors are potent gamma-globin gene inducers and that the concentration range of their effects on gamma gene expression can be correlated roughly with their HDAC inhibitory potencies.
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Affiliation(s)
- Evangelia Skarpidi
- Division of Medical Genetics, University of Washington, Seattle, Wash 98195, USA
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Abstract
Iron transport in the plasma is carried out by transferrin, which donates iron to cells through its interaction with a specific membrane receptor, the transferrin receptor (TfR). A soluble form of the TfR (sTfR) has been identified in animal and human serum. Soluble TfR is a truncated monomer of tissue receptor, lacking its first 100 amino acids, which circulates in the form of a complex of transferrin and its receptor. The erythroblasts rather than reticulocytes are the main source of serum sTfR. Serum sTfR levels average 5.0+/-1.0 mg/l in normal subjects but the various commercial assays give disparate values because of the lack of an international standard. The most important determinant of sTfR levels appears to be marrow erythropoietic activity which can cause variations up to 8 times below and up to 20 times above average normal values. Soluble TfR levels are decreased in situations characterized by diminished erythropoietic activity, and are increased when erythropoiesis is stimulated by hemolysis or ineffective erythropoiesis. Measurements of sTfR are very helpful to investigate the pathophysiology of anemia, quantitatively evaluating the absolute rate of erythropoiesis and the adequacy of marrow proliferative capacity for any given degree of anemia, and to monitor the erythropoietic response to various forms of therapy, in particular allowing to predict response early when changes in hemoglobin are not yet apparent. Iron status also influences sTfR levels, which are considerably elevated in iron deficiency anemia but remain normal in the anemia of inflammation, and thus may be of considerable help in the differential diagnosis of microcytic anemia. This is particularly useful to identify concomitant iron deficiency in a patient with inflammation because ferritin values are then generally normal. Elevated sTfR levels are also the characteristic feature of functional iron deficiency, a situation defined by tissue iron deficiency despite adequate iron stores. The sTfR/ferritin ratio can thus describe iron availability over a wide range of iron stores. With the exception of chronic lymphocytic leukemia (CLL) and high-grade non-Hodgkin's lymphoma and possibly hepatocellular carcinoma, sTfR levels are not increased in patients with malignancies. We conclude that soluble TfR represents a valuable quantitative assay of marrow erythropoietic activity as well as a marker of tissue iron deficiency.
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Affiliation(s)
- Yves Beguin
- Department of Medicine, Division of Hematology, University of Liège, CHU Sart Tilman, 4000 Liège, Belgium.
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Steinberg MH, Voskaridou E, Kutlar A, Loukopoulos D, Koshy M, Ballas SK, Castro O, Barton F. Concordant fetal hemoglobin response to hydroxyurea in siblings with sickle cell disease. Am J Hematol 2003; 72:121-6. [PMID: 12555216 DOI: 10.1002/ajh.10264] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Fetal hemoglobin (HbF) level and the HbF responses to hydroxyurea (HU) vary among patients with sickle cell disease and are, at least in part, genetically regulated. We hypothesized that siblings with sickle cell disease are likely to share the same parental beta-like globin gene clusters with their cis-acting regulatory sequences and therefore, if regulation of this response is linked to the beta-globin gene cluster, might have concordant HbF responses to HU. Accordingly, we studied 26 families (30 sib pairings), 20 with sickle cell anemia (three families had three siblings) and 6 families with HbS-beta-thalassemia (one family had three siblings, and one family consisted of monozygotic twins), to see if siblings with sickle cell disease had discordant or concordant changes in HbF during HU treatment. Intraclass correlation coefficients (r) showed a high, positive correlation between sibs for HbF levels before and during HU treatment and a concordant change in HbF response from baseline to treatment-associated levels. Changes in mean corpuscular volume (MCV) paralleled HbF levels, while the expected correlations between treatment-associated fall in leukocyte count and increase in MCV were also present. Our results provide additional evidence that some elements that regulate HbF expression are linked to the beta-globin gene cluster.
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Affiliation(s)
- Martin H Steinberg
- Boston University School of Medicine, Room 211, 88 E. Newton Street, Boston, MA 02118, USA.
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Affiliation(s)
- Christina Halsey
- Department of Haematology, Great Ormond Street Hospital for Sick Children, London, UK
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Atweh GF, Loukopoulos D. Pharmacological induction of fetal hemoglobin in sickle cell disease and beta-thalassemia. Semin Hematol 2001; 38:367-73. [PMID: 11605172 DOI: 10.1016/s0037-1963(01)90031-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
A number of pharmacological agents are currently available for the induction of fetal hemoglobin (HbF) in patients with sickle cell disease and beta-thalassemia. Here we review the development of this new class of therapeutics and summarize the clinical trials that investigate their efficacy in patients with hemoglobin disorders. Hydroxyurea is the first of these drugs to be approved by the Food and Drug Administration for the treatment of sickle cell disease. Currently, the major focus is the development of safer agents and combinations of drugs that can increase HbF to levels high enough to prevent all complications of the disease. Progress in adapting the same strategy to the treatment of thalassemic disorders has been much slower. Although all the agents that are effective in sickle cell disease have similar HbF-inducing activity in beta-thalassemia, their use has rarely resulted in significant amelioration of the anemia. More research and more effective agents will be needed to make a significant impact on thalassemia. Nonetheless, success in this relatively young field has been very gratifying; before the end of this decade, clinically meaningful induction of HbF may become an achievable goal in most patients with hemoglobin disorders.
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Affiliation(s)
- G F Atweh
- Division of Hematology, Mount Sinai School of Medicine, New York, NY 10029, USA
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