Time filter

Source Type

Budapest, Hungary

Lautner-Csorba O.,Semmelweis University | Gezsi A.,Semmelweis University | Semsei A.F.,Semmelweis University | Antal P.,Budapest University of Technology and Economics | And 9 more authors.
BMC Medical Genomics | Year: 2012

Background: We carried out a candidate gene association study in pediatric acute lymphoblastic leukemia (ALL) to identify possible genetic risk factors in a Hungarian population. Methods. The results were evaluated with traditional statistical methods and with our newly developed Bayesian network based Bayesian multilevel analysis of relevance (BN-BMLA) method. We collected genomic DNA and clinical data from 543 children, who underwent chemotherapy due to ALL, and 529 healthy controls. Altogether 66 single nucleotide polymorphisms (SNPs) in 19 candidate genes were genotyped. Results: With logistic regression, we identified 6 SNPs in the ARID5B and IKZF1 genes associated with increased risk to B-cell ALL, and two SNPs in the STAT3 gene, which decreased the risk to hyperdiploid ALL. Because the associated SNPs were in linkage in each gene, these associations corresponded to one signal per gene. The odds ratio (OR) associated with the tag SNPs were: OR = 1.69, P = 2.22x10§ssup§- 7§esup§ for rs4132601 (IKZF1), OR = 1.53, P = 1.95x10§ssup§- 5§esup§ for rs10821936 (ARID5B) and OR = 0.64, P = 2.32x10§ssup§-4§esup§ for rs12949918 (STAT3). With the BN-BMLA we confirmed the findings of the frequentist-based method and received additional information about the nature of the relations between the SNPs and the disease. E.g. the rs10821936 in ARID5B and rs17405722 in STAT3 showed a weak interaction, and in case of T-cell lineage sample group, the gender showed a weak interaction with three SNPs in three genes. In the hyperdiploid patient group the BN-BMLA detected a strong interaction among SNPs in the NOTCH1, STAT1, STAT3 and BCL2 genes. Evaluating the survival rate of the patients with ALL, the BN-BMLA showed that besides risk groups and subtypes, genetic variations in the BAX and CEBPA genes might also influence the probability of survival of the patients. Conclusions: In the present study we confirmed the roles of genetic variations in ARID5B and IKZF1 in the susceptibility to B-cell ALL. With the newly developed BN-BMLA method several gene-gene, gene-phenotype and phenotype-phenotype connections were revealed. We showed several advantageous features of the new method, and suggested that in gene association studies the BN-BMLA might be a useful supplementary to the traditional frequentist-based statistical method. © 2012 Lautner-Csorba et al.; licensee BioMed Central Ltd.

Semsei A.F.,Semmelweis University | Erdelyi D.J.,Semmelweis University | Ungvari I.,Semmelweis University | Csagoly E.,Semmelweis University | And 11 more authors.
Cell Biology International | Year: 2012

Anthracyclines are potent cytostatic drugs, the correct dosage being critical to avoid possible cardiac side effects. ABCC1 [ATP-binding cassette, sub-family C, member 1; also denoted as MRP1 (multidrug resistance-associated protein 1)] is expressed in the heart and takes part in the detoxification and protection of cells from the toxic effects of xenobiotics, including anthracyclines. Our objective was to search for associations between LV (left ventricular) function and single-nucleotide polymorphisms of the ABCC1 gene in children receiving anthracycline chemotherapy. Data of 235 paediatric patients with acute lymphoblastic leukaemia was analysed. Patients were followed-up by echocardiography (median follow-up 6.3 years). Nine polymorphisms in the ABCC1 gene were genotyped. The ABCC1 rs3743527TT genotype and rs3743527TT-rs246221TC/TT genotype combination were associated with lower LVFS (left ventricular fractional shortening) after chemotherapy. The results suggest that genetic variants in the ABCC1 gene influence anthracycline-induced LV dysfunction. © The Author(s) Journal compilation © 2012 Portland Press Limited.

Ungvari I.,Semmelweis University | Hadadi E.,Semmelweis University | Virag V.,Semmelweis University | Nagy A.,Heim Pal Pediatric Hospital | And 8 more authors.
Journal of Community Genetics | Year: 2012

Air pollution and subsequent increased oxidative stress have long been recognized as contributing factors for asthma phenotypes. Individual susceptibility to oxidative stress is determined by genetic variations of the antioxidant defence system. In this study, we analysed the association between environmental nitrogen dioxide (NO2) exposure and single nucleotide polymorphisms (SNP) in NFE2L2 and KEAP1 genes and their common impact on asthma risk. We genotyped 12 SNPs in a case-control study of 307 patients diagnosed with asthma and 344 controls. NO2 concentration was collected from the period preceding the development of asthma symptoms. Multiple logistic regression was applied to evaluate the effects of the studied genetic variations on asthma outcomes in interaction with NO2 exposure. Our data showed that genotypes of rs2588882 and rs6721961 in the regulatory regions of the NFE2L2 gene were inversely associated with infection-induced asthma (odds ratio (OR)00.290, p00.0015, and OR00.437, p0 0.007, respectively). Furthermore, case-only analyses revealed significant differences for these SNPs between asthma patients that lived in modestly or highly polluted environment (OR00.43 (0.23-0.82), p00.01, and OR0 0.51, p00.02, respectively, in a dominant model). In conclusion, our results throw some new light upon the impact of NFE2L2 polymorphisms on infection-induced asthma risk and their effect in gene-environment interactions. © Springer-Verlag 2011.

Lautner-Csorba O.,Semmelweis University | Gezsi A.,Semmelweis University | Erdelyi D.J.,Semmelweis University | Hullam G.,Budapest University of Technology and Economics | And 7 more authors.
PLoS ONE | Year: 2013

In this study we investigated whether polymorphisms in the folate pathway influenced the risk of childhood acute lymphoblastic leukemia (ALL) or the survival rate of the patients. For this we selected and genotyped 67 SNPs in 15 genes in the folate pathway in 543 children with ALL and 529 controls. The results were evaluated by gender adjusted logistic regression and by the Bayesian network based Bayesian multilevel analysis of relevance (BN-BMLA) methods. Bayesian structure based odds ratios for the relevant variables and interactions were also calculated. Altogether 9 SNPs in 8 genes were associated with altered susceptibility to ALL. After correction for multiple testing, two associations remained significant. The genotype distribution of the MTHFD1 rs1076991 differed significantly between the ALL and control population. Analyzing the subtypes of the disease the GG genotype increased only the risk of B-cell ALL (p = 3.52×10-4; OR = 2.00). The GG genotype of the rs3776455 SNP in the MTRR gene was associated with a significantly reduced risk to ALL (p = 1.21×10-3; OR = 0.55), which resulted mainly from the reduced risk to B-cell and hyperdiploid-ALL. The TC genotype of the rs9909104 SNP in the SHMT1 gene was associated with a lower survival rate comparing it to the TT genotype (80.2% vs. 88.8%; p = 0.01). The BN-BMLA confirmed the main findings of the frequentist-based analysis and showed structural interactional maps and the probabilities of the different structural association types of the relevant SNPs especially in the hyperdiploid-ALL, involving additional SNPs in genes like TYMS, DHFR and GGH. We also investigated the statistical interactions and redundancies using structural model properties. These results gave further evidence that polymorphisms in the folate pathway could influence the ALL risk and the effectiveness of the therapy. It was also shown that in gene association studies the BN-BMLA could be a useful supplementary to the traditional frequentist-based statistical method. © 2013 Lautner-Csorba et al.

Ersek B.,Hungarian Academy of Sciences | Ersek B.,Semmelweis University | Lupsa N.,Hungarian Academy of Sciences | Lupsa N.,Semmelweis University | And 16 more authors.
Cellular and Molecular Life Sciences | Year: 2016

T-cell receptor (TCR)-transgenic models of acute graft-versus-host disease (aGvHD) offer a straightforward and highly controlled approach to study the mechanisms and consequences of T-cell activation following allogeneic hematopoietic stem cell transplantation (aHSCT). Here, we report that aHSCT involving OT-I mice as donors, carrying an ovalbumin-specific CD8+ TCR, and Act-mOVA mice as recipients, expressing membrane-bound ovalbumin driven by the β-actin promoter, induces lethal aGvHD in a CD8+ T-cell-dependent, highly reproducible manner, within 4–7 days. Tracking of UBC-GFP/OT-I graft CD8+ T cells disclosed heavy infiltration of the gastrointestinal tract, liver, and lungs at the onset of the disease, and histology confirmed hallmark features of gastrointestinal aGVHD, hepatic aGvHD, and aGvHD-associated lymphocytic bronchitis in infiltrated organs. However, T-cell infiltration was virtually absent in the skin, a key target organ of human aGvHD, and histology confirmed the absence of cutaneous aGVHD, as well. We show that the model allows studying CD8+ T-cell responses in situ, as selective recovery of graft CD45.1/OT-I CD8+ T cells from target organs is simple and feasible by automated tissue dissociation and subsequent cell sorting. Assessment of interferon-gamma production by flow cytometry, granzyme-B release by ELISA, TREC assay, and whole-genome gene expression profiling confirmed that isolated graft CD8+ T cells remained intact, underwent clonal expansion, and exerted effector functions in all affected tissues. Taken together, these data demonstrate that the OT-I/Act-mOVA model is suitable to study the CD8+ T-cell-mediated effector mechanisms in a disease closely resembling fatal human gastrointestinal and hepatic aGVHD that may develop after aHSCT using HLA-matched unrelated donors. © 2016 Springer International Publishing

Discover hidden collaborations