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Objective: The use of fetal hemoglobin (HbF) inducer drugs is considered as a novel approach in treatment of β-hemoglobinopathies, especially β- thalassemia and sickle cell disease. HbF inducers including hydroxyurea, histone deacetylase (HDAC) inhibitor agents such as sodium butyrate, azacitidine, decitabine and new immunomodulator drugs like pomalidomide, lenalidomide and thalidomide can reduce α-globin chain production in erythroid progenitors and improve α: β chain imbalance, the most crucial complication of β-thalassemia. Materials and Methods: In this article, we reviewed more than 40 articles published from 1979 to 2012 in the field of fetal hemoglobin augmentation. Results: Recent studies suggest the synergistic effect of drug combinations in efficient induction of fetal hemoglobin and gene over-expression. Conclusion: It seems that drugs which act with different molecular and epigenetic mechanisms have proper synergistic effects in fetal hemoglobin induction and gene over-expression.

Potent induction of fetal hemoglobin (HbF) production results in alleviating the complications of β-thalassemia and sickle cell disease (SCD). HbF inducer agents can trigger several molecular signaling pathways critical for erythropoiesis. Janus kinase/Signal transducer and activator of transcription (JAK/STAT), mitogen activated protein kinas (MAPK) and Phosphoinositide 3-kinase (PI3K) are considered as main signaling pathways, which may play a significant role in HbF induction. All these signaling pathways are triggered by erythropoietin (EPO) as the main growth factor inducing erythroid differentiation, when it binds to its cell surface receptor, erythropoietin receptor (EPO-R) HbF inducer agents have been shown to upregulate HbF production level by triggering certain signaling pathways. As a result, understanding the pivotal signaling pathways influencing HbF induction leads to effective upregulation of HbF. In this mini review article, we try to consider the correlation between HbF inducer agents and their molecular mechanisms of γ-globin upregulation. Several studies suggest that activating P38 MAPK, RAS and STAT5 signaling pathways result in efficient HbF induction. Nevertheless, the role of other erythroid signaling pathways in HbF induction seems to be indispensible and should be emphasized.

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Hemoglobin F (HbF, α2γ2) is a major contributor to the clinical heterogeneity and ameliorating agent observed in patients with the β-globin disorders including β-thalassemia and sickle cell disease (SCD). During fetal life, HbF is the major hemoglobin but is largely substituted by adult hemoglobin (HbA, α2β2) following a globin expression switch after birth. Increased γ-globin expression can reduce the clinical severity of β-thalassemia and SCD. Therefore, increase in HbF production has served as a longstanding goal. The progression of target-based therapeutics has been confused by limited comprehension of molecular mechanisms of gamma-globin gene expression. However, recent discoveries of regulators of HbF level represent a major development and provide new opportunities in employing novel rational therapeutic strategies. In this review, molecular mechanisms of hemoglobin F induction will be discussed.

Histone deacetylases (HDACs) are the enzymes causing deacetylation of histone and non-histone substrates. Histone deacetylase inhibitors (HDIs) are a family of drugs eliminating the effect of HDACs in malignant cells via inhibition of HDACs. Due to extensive effects upon gene expression through interference with fusion genes and transcription factors, HDACs cause proliferation and migration of malignant cells, inhibiting apoptosis in these cells via tumor suppressor genes. Over expression evaluation of HDACs in leukemias may be a new approach for diagnosis of leukemia, which can present new targets for leukemia therapy. HDIs inhibit HDACs, increase acetylation in histones, cause up- or down regulation in some genes and result in differentiation, cell cycle arrest and apoptosis induction in malignant cells via cytotoxic effects. Progress in identification of new HDIs capable of tracking several targets in the cell can result in novel achievements in treatment and increase survival in patients. In this review, we examine the role of HDACs as therapeutic targets in various types of leukemia as well as the role of HDIs in inhibition of HDACs for treatment of these malignancies.

MicroRNAs are 19–22 nucleotide RNAs involved in such important processes as development, proliferation, differentiation and apoptosis. Different miRNAs are uniquely expressed in lymphoid T cells, and play a role indevelopment and differentiation of various subtypes by targeting their target genes. Recent studies have shown that aberrant miRNA expression may be involved in T cell leukemogenesis and lymphogenesis, and may function as tumor suppressor (such as miR-451, miR-31, miR-150, and miR-29a) or oncogene (e.g. miR-222, miR-223, miR-17-92, miR-155). MiRNAs can be used as new biomarkers for prognosis and diagnosis or as an index of disease severity in T-cell leukemia and lymphoma. This article presents a review of studies in recent years on the role of miRNAs in T-cell development and their aberrant expression in pathogenesis of T-cell leukemia and lymphoma. Characterizing miRNAs can help recognize their role as new important molecules with prognostic and therapeutic applications.

Background: Hemoglobinopathy and thalassemia are prevalent genetic disorders throughout the world. Beta thalassemia is one of these disorders with high prevalence in Iran, especially in Khuzestan province. In this study, the rate of different mutations in β-globin gene for prenatal diagnosis in fetal samples was evaluated. Materials and methods: In this experimental pilot study, 316 fetal samples (chorionic villus or amniotic fluid) suspicious to hemoglobin disorders were enrolled. Afterwards, DNA was extracted and PCR and DNA sequencing were used for evaluation of different mutations in β-globin gene. Results: Amongst 316 samples evaluated for prenatal diagnosis, 180 cases (56.8%) were carrying at least one mutated gene of β-thalassemia. In addition, results showed that CD 36-37 (- T) and IVS II-1 (G>A) polymorphisms are the most prevalent polymorphisms of β-thalassemia in Ahvaz city with 13.9% and 10.1% rates, respectively. Conclusion: Using molecular tests for prenatal diagnosis is considered an efficient approach for reducing the birth of children with hemoglobinopathy and identification of prevalent mutations in each region.

Background: Immune thrombocytopenic purpura (ITP) is an autoimmune disease that can cause bleeding disorders in patients, and presents in acute and chronic forms. The acute form is frequently seen in children, but the chronic form mainly inflicts adults. There are differences and similarities in clinical and laboratory findings of the disease between children and adults. We study these differences and similarities in these two groups of patients with ITP. Methods: In this study, we retrospectively evaluated the clinical and laboratory data of 323 ITP cases within three years. None of our patients had a history of thrombocytopenia. Patients were classified into two groups of children (3 months to 16 years of age) and adults (≥ 16 years). Data analysis was conducted using SPSS software, and the analysis results were compared between the two age groups. Results: Overall, the disease prevalence was higher in women than men, but the prevalence of childhood ITP was higher in males than females. The prevalence of initial symptoms including petechiae, purpura and ecchymosis was 60.5% and 61%, respectively in all patients, but severe bleeding rarely occurred in patients (28.8%). 30.5% of patients had a history of infection before developing ITP, and the children had a higher frequency of infection (80.8%). Before treatment, the mean platelet count in adults and children was 33000/μL and 35000/μL, respectively. Conclusion: Comparison of data in children and adults with ITP indicated similarities and differences in clinical and laboratory findings between the two groups with differences in prevalence, bleeding symptoms, initial platelet count and infection history.