Iman A. Shaheen

The association between hepatitis C virus infection, genetic polymorphisms of oxidative stress genes and B-cell non-Hodgkin's lymphoma risk in Egypt.

Hepatitis C virus (HCV) has been postulated to be an etiological agent for lymphoid malignancies. Polymorphisms in oxidative stress genes as; superoxide dismutase (SOD2), glutathione peroxidase (GPX1), catalase (CAT), myeloperoxidase (MPO) and nitric oxide synthase (NOS2) may influence non-Hodgkins lymphoma (NHL) risk. HCV screening and polymorphisms in these five genes coding for antioxidant enzymes were studied in 100 Egyptian patients with B cell-NHL and 100 controls to clarify the association between HCV infection, oxidative stress genes polymorphisms and B cell-NHL risk. A significantly higher prevalence of HCV infection was detected among NHL patients relative to controls and this carried a 14-fold increased NHL risk (odds ratio (OR)=14.3, 95% confidence interval (CI)=5.4-38.3, p<0.0001). GPX1 and MPO genetic polymorphisms conveyed increase in B-NHL risk (OR=3.3, 95% CI=1.4-7.4, p=0.004 and OR=4.4, 95% CI=1.3-14.2, p=0.009 respectively). Further analyses stratified by HCV infection revealed that concomitant HCV infection and GPX1 gene polymorphism had a synergetic effect on NHL risk with an OR of 15 (95%CI=2.2-69.6, p<0.0001). In addition, combined HCV infection and MPO gene polymorphisms had a pronounced NHL risk (OR=9.2, 95%CI=2.5-33.9, p<0.0001). SOD2, CAT and NOS2 genetic polymorphisms were not found to confer increased NHL risk. This study revealed that HCV infection is a risk factor for NHL in Egypt. Polymorphisms in GPX1 and MPO genes may influence NHL risk in HCV infected Egyptian patients. Larger scale studies are warranted to establish this genetic susceptibility for NHL.

FcγRIIa and FcγRIIIa genetic polymorphisms in a group of pediatric immune thrombocytopenic purpura in Egypt.

Immune thrombocytopenic purpura (ITP) is an acquired autoimmune disorder caused by the production of antiplatelet antibodies. The current case-control study aimed at detecting the frequency of Fc&ggr;RIIa-131H/R and Fc&ggr;RIIIa-158F/V genes polymorphism in Egyptian children with ITP as genetic markers for ITP risk, and to clear out their possible role in choosing the treatment protocols of ITP. To achieve this aim, Fc&ggr;RIIa genotyping was tested by PCR-restriction fragment length polymorphism (RFLP) technique, whereas Fc&ggr;RIIIa genotyping was tested by nested PCR followed RFLP analysis. The current case-control study was conducted on 92 children with ITP; 12 acute and 80 chronic cases and 90 controls. The V allele and Fc&ggr;RIIIa FV heterotype were significantly higher in ITP patients and conferred increased ITP risk [odds ratio (OR) = 1.96 and 2.55, respectively]. The frequency of Fc&ggr;RIIa H allele was significantly higher among chronic ITP patients. In conclusion, Fc&ggr;RIIIa gene polymorphism may contribute to susceptibility to ITP. Moreover, analysis of the Fc&ggr;R polymorphisms in ITP patients could influence the effectiveness of medications and selection of the line of treatment.

Blood transfusion among thalassemia patients: A single Egyptian center experience

Background: Although red cell transfusions are lifesavers for patients with thalassemia, they are responsible for a series of complications and expose the patients to a variety of risks. Material and Methods: This cross-sectional study included 464 Egyptian beta(β) thalassemia major patients whose age ranged between 10 months and 31 years (mean 10.2 ± 6.6 years). All patients were subjected to thorough history taking with special emphasis on blood transfusions regarding rate of blood transfusion, type of received blood, and history of previous transfusion reactions in addition to type of chelation and compliance to iron chelation therapy and history of diabetes. Serum ferritin and pretransfusion hemoglobin assessment were done for all patients. Results: The mean pretransfusion hemoglobin level was 5.7 ± 1.16 g/dl. Allergic reactions were observed in 3.9% of the patients during the period of the study, while the history of previous allergic reaction was given by 72% of the patients. Deferiprone showed better compliance (58.6%) than deferoxamine (26.3%). The prevalence of diabetes was 10.1% among the studied group. On comparing diabetics to nondiabetics, serum ferritin, transfusion intervals, and age were statistically higher among diabetics (P<0.001). Conclusion: Lower pretransfusion hemoglobin and high rate of prevalence of diabetes, in addition to better compliance to deferiprone than deferoxamine, were detected among the patients.

Methylene tetrahydrofolate reductase (MTHFR) gene polymorphisms in chronic myeloid leukemia: an Egyptian study.

Abstract Methylenetetrahydrofolate reductase (MTHFR) gene plays a pivotal role in folate metabolism. Several genetic variations in MTHFR gene as MTHFR-C677T and MTHFR-A1298C result in decreased MTHFR activity, which could influence efficient DNA methylation and explain susceptibility to different cancers. The etiology of chronic myeloid leukemia (CML) is obscure and little is known about individual’s susceptibility to CML. In order to assess the influence of these genetic polymorphisms on the susceptibility to CML and its effect on the course of the disease among Egyptians, we performed an age–gender–ethnic matched case–control study. The study included 97 CML patients and 130 healthy controls. Genotyping of MTHFR-C677T and -A1298C was performed by polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) technique. The results showed no statistical difference in the distribution of MTHFR-C677T and -A1298C polymorphic genotypes between CML patients and controls. The frequency of MTHFR 677-TT homozygous variant was significantly higher in patients with accelerated/blastic transformation phase when compared to those in the chronic phase of the disease. In conclusion, our study revealed that MTHFR-C677T and -A1298C polymorphisms could not be considered as genetic risk factors for CML in Egyptians. However, MTHFR 677-TT homozygous variant might be considered as a molecular predictor for disease progression.

Apolipoprotein E gene polymorphism and the risk of left ventricular dysfunction among Egyptian β-thalassemia major

In Egypt, β-thalassemia is the most common hereditary hemolytic anemia. Cardiac dysfunction, secondary to iron overload with formation of oxygen free radicals, is the most common cause of death in β-thalassemia patients. This study was designed to determine whether the allelic genotype of apolipoprotein E (Apo E), which exhibits antioxidant properties, could represent a genetic risk factor for the development of left ventricular (LV) dysfunction in β-thalassemia major. Fifty Egyptian β-thalassemia major patients were subjected to echocardiography to assess LV function. Apo E genotyping by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) was done for all patients in addition to 50 age and sex matched healthy control subjects. Patients were classified into three groups. Group I and II were clinically asymptomatic. Group II subjects had evidence of LV dilatation, while Group III patients had clinical and echocardiographic findings of LV failure. Apo E4 allele was significantly higher among Group II and III than in controls. In conclusion, Apo E4 allele can be considered as a genetic risk factor for LV dysfunctions in β-thalassemic patients. It could be used as predictive indicator for additional risk of LV failure, particularly in asymptomatic patients with LV dilatation, requiring a closer follow-up, to prevent further disease progression.

Incidence and Association of 563 C/T Mediterranean and the Silent 1311C/T G6PD Mutations in G6PD-deficient Egyptian Children

Background: Molecular characterization of glucose-6-phosphate dehydrogenase (G6PD) deficiency variants is essential, especially since the biochemical characterization has lost its significance due to the individual variability. As a result, cases can be misdiagnosed. The present study was designed to determine the incidence of G6PD Mediterranean (Med) mutation among Egyptian children with G6PD deficiency as well as its molecular association with the G6PD 1311T silent polymorphism. Methods: Fifty G6PD-deficient children were subjected to quantitative G6PD enzyme assay. A polymerase chain reaction-amplification refractory mutation system (PCR-ARMS) technique was used to detect the G6PD Med mutation, and polymerase chain reactionrestriction fragment length polymorphism (PCRRFLP) was used to assess the associated G6PD 1311T silent polymorphism. Results: G6PD Med was found in 62% and G6PD 1311T polymorphism in 52% of the patients. The association between both mutations was statistically significant. Conclusion: Glucose-6-phosphate dehydrogenase Med mutation is 1 of the most common mutations causing G6PD deficiency among Egyptian children with G6PD deficiency, with linkage disequilibrium between this G6PD mutation and thymine at nucleotide (nt) 1311.

Peripheral expression of hepcidin gene in Egyptian β-thalassemia major

Iron overload is the major cause of morbidity and mortality in transfusion dependent β-thalassemia major patients. There is a sophisticated balance of body iron metabolism of storage and transport which is regulated by several factors including the peptide hepcidin. Hepcidin is the main iron regulatory molecule; it is secreted mainly by the liver and other tissues including monocytes and lymphocytes. Expression of hepcidin in such cells is unclear and has been studied in few reports with controverted result. Peripheral expression of hepcidin was measured using quantitative real time PCR (qRT-PCR) in 50 β-thalassemia major patients, in addition to 20 healthy volunteers as a control group. Hepcidin levels in β-thalassemia major patients showed statistically significant decrease in comparison to the control group, and was correlated to cardiac iron stores (T2*). However, hepcidin level was not different among the patients according to the HCV status or whether splenectomized or not. In conclusion; peripheral expression of hepcidin, in iron overloaded β-thalassemia major patients, is a reflection of hepatic expression. It can be used as a molecular predictor for the severity of cardiac iron overload and can be used as a future target for therapy in β-thalassemia major patients.

Detection of expression of IL-18 and its binding protein in Egyptian pediatric immune thrombocytopenic purpura

Abstract Immune thrombocytopenic purpura (ITP) is an autoimmune disorder, characterized by dysfunctional cellular immunity including the presence of activated platelet specific autoreactive T cells that recognize and respond to autologous platelet antigens. Autoreactive T cells drive the generation of platelet reactive autoantibodies by B cells as well as T-cytotoxic cell-mediated lysis of platelets. Interleukin-18 (IL-18) is a mediator of T helper type 1 cell responses synergistically with IL-12 that initiate and promote host defense and inflammation. IL-18 has a specific binding protein (IL-18BP) which belongs to the immunoglobulin superfamily. In the present study, serum level and messenger RNA( mRNA) expression of IL-18 as well as IL-18BP mRNA expression were measured in peripheral blood mononuclear cells (PBMNCs) of 100 Egyptian pediatric patients with ITP (70 acute and 30 chronic). In addition to this, we recruited 80 healthy volunteers in order to investigate the possible association between the imbalance of IL-18 and IL-18 BP expressions and the pathogenesis of ITP. IL-18 serum level and mRNA expression were not elevated in cases more than in the control group, but IL-18 mRNA was higher in chronic cases when compared to the acute ones (p = 0.031) and there was a good negative correlation between the platelet count and serum IL-18. IL-18 BP m-RNA was slightly elevated in cases more than in the control group (95% Confidence interval = 1.15–2.01). Our results were not supportive for previous findings of elevated IL18/BP mRNA ratio in ITP patients. This could be referred to the fact that autoimmune diseases are complex genetic disorders, therefore further studies on polymorphisms affecting IL-18 gene expression as well as kinetics of IL-18 expression are required to evaluate the role of interleukin 18 and its binding protein in the pathogenesis of ITP.

DNMT3B promoter polymorphism and risk of immune thrombocytopenic purpura in pediatric Egyptians.

Idiopathic (immune) thrombocytopenic purpura (ITP) is a heterogeneous clinical disorder characterized by immune-mediated platelet destruction. Epigenetic changes in gene expression, including DNA methylation and histone modifications, might contribute to autoimmunity. Polymorphisms of the DNA methyltransferase 3B (DNMT3B) gene may influence DNMT3B activity on DNA methylation and increase the susceptibility to several diseases. The current study investigated the association between a single nucleotide polymorphism (SNP) in the promoter of DNMT3B gene and the risk for ITP in pediatric Egyptians. DNMT3B SNP was genotyped by PCR–restriction fragment length polymorphism in 71pediatric ITP patients and 82 healthy controls matched for age and sex. The C/C wild genotype was not detected in ITP patients or in the controls. The frequencies of the T/T and C/T genotypes were 93.9 and 8.5% in the controls and 91.5 and 8.5% in ITP patients, respectively. There was no significant difference in either genotypes or allelic distribution between ITP patients and the controls. In conclusion, this polymorphism was almost equally distributed between ITP patients and the controls. These results demonstrated that this SNP may not be used as a stratification marker to predict the susceptibility to childhood ITP in Egypt.

Quantitative assessment of Wilms tumor 1 (WT1) gene transcripts in Egyptian acute lymphoblastic leukemia patients.

Background Accurate assessment of minimal residual disease (MRD) in acute lymphoblastic leukemia (ALL) patients after initial chemotherapy is essential to evaluate the efficacy of therapeutic regimens. Wilms tumor 1 (WT1) is a pan-leukemic marker used for identification of the leukemic clone rather than the use of individual specific molecular aberration of ALL. Methods Using a real-time quantitative polymerase chain reaction, bone marrow samples from 41 newly diagnosed Egyptian ALL patients; 22 adults and 19 children were examined for WT1 expression. After induction therapy, WT1 expression was reestimated in 20 ALL patients. Results WT1 was overexpressed in adult and pediatric ALL patients (95.4% and 89.4%, respectively). WT1 expression at diagnosis had no statistically significant impact on disease-free survival of patients (P = 0.054). However, WT1 expression increased after induction chemotherapy in the 3 pediatric patients who had relapse. Conclusions WT1 is a leukemia-associated molecular marker that may be used for the diagnosis and for monitoring clinical progress in ALL; it also can be used as a molecular target for adoptive immunotherapy.