Genetic Variation in Cell Death Genes and Risk of Non-Hodgkin Lymphoma
ABSTRACT Non-Hodgkin lymphomas are a heterogeneous group of solid tumours that constitute the 5(th) highest cause of cancer mortality in the United States and Canada. Poor control of cell death in lymphocytes can lead to autoimmune disease or cancer, making genes involved in programmed cell death of lymphocytes logical candidate genes for lymphoma susceptibility.
We tested for genetic association with NHL and NHL subtypes, of SNPs in lymphocyte cell death genes using an established population-based study. 17 candidate genes were chosen based on biological function, with 123 SNPs tested. These included tagSNPs from HapMap and novel SNPs discovered by re-sequencing 47 cases in genes for which SNP representation was judged to be low. The main analysis, which estimated odds ratios by fitting data to an additive logistic regression model, used European ancestry samples that passed quality control measures (569 cases and 547 controls). A two-tiered approach for multiple testing correction was used: correction for number of tests within each gene by permutation-based methodology, followed by correction for the number of genes tested using the false discovery rate.
Variant rs928883, near miR-155, showed an association (OR per A-allele: 2.80 [95% CI: 1.63-4.82]; p(F) = 0.027) with marginal zone lymphoma that is significant after correction for multiple testing.
This is the first reported association between a germline polymorphism at a miRNA locus and lymphoma.
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ABSTRACT: MicroRNA (miRNA), which plays an important role in tumorigenesis, can regulate post-transcriptional gene expression by binding to the 3' untranslated regions (3'-UTRs) of messenger RNAs and repressing its translation. Several single nucleotide polymorphisms (SNPs) are considered to have significant impacts on susceptibility of the role these genetic polymorphisms in development of carcinogenesis through that mechanism. But few of them focus their impact on non-Hodgkin's lymphoma (NHL). Therefore, we conducted this study to investigate the associations between the genetic variants and cancer risk or cancer outcome. MiRNA-related single nucleotide polymorphism (miR-SNP) sites rs3660 of KRT81, rs1044129 of RYR3, rs4901706 of f101, and rs1053667 of KIAA0423 were selected and analyzed in 210 patients in NHL to evaluate their association with cancer risk and prognosis. The results indicated that none of them is associated with the cancer risk in NHL. Otherwise KRT81 rs3660 GG type is associated with a shorter survival time (p=0.012), after being assessed by multivariate Cox analyses, its effect on prognosis was verified (p=0.003). It suggests that KRT81 rs3660 GG type is an independent prognostic marker in NHL.Gene 02/2014; DOI:10.1016/j.gene.2014.02.010 · 2.08 Impact Factor
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ABSTRACT: The human immune system depends on the activity of cytotoxic T lymphocytes (CTL), natural killer (NK) cells, and NKT cells in order to fight off a viral infection. Understanding the molecular mechanisms during this process and the role of individual proteins was greatly improved by the study of familial hemophagocytic lymphohistiocytosis (FHL). Since 1999, genetic sequencing is the gold standard to classify patients into different subgroups of FHL. The diagnosis, once based on a clinical constellation of abnormalities, is now strongly supported by the results of a functional flow-cytometry screening, which directs the genetic study. A few additional congenital immune deficiencies can also cause a resembling or even identical clinical picture to FHL. As in many other rare human disorders, the collection and analysis of a relatively large number of cases in registries is crucial to draw a complete picture of the disease. The conduction of prospective therapeutic trials allows investigators to increase the awareness of the disease and to speed up the diagnostic process, but also provides important functional and genetic confirmations. Children with confirmed diagnosis may undergo hematopoietic stem cell transplantation, which is the only cure known to date. Moreover, detailed characterization of these rare patients helped to understand the function of individual proteins within the exocytic machinery of CTL, NK, and NKT cells. Moreover, identification of these genotypes also provides valuable information on variant phenotypes, other than FHL, associated with biallelic and monoallelic mutations in the FHL-related genes. In this review, we describe how detailed characterization of patients with genetic hemophagocytic lymphohistiocytosis has resulted in improvement in knowledge regarding contribution of individual proteins to the functional machinery of cytotoxic T- and NK-cells. The review also details how identification of these genotypes has provided valuable information on variant phenotypes.Frontiers in Immunology 04/2014; 5:167. DOI:10.3389/fimmu.2014.00167
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ABSTRACT: Non-Hodgkin lymphomas (NHL) entail considerable heterogeneity regarding their morphology, clinical course, etiological factors, or response to therapy. Increased incidence of NHL in immunocompromised individuals and after autoimmune diseases suggests that infections and immune dysregulation could play a role in the susceptibility to NHL. Accordingly, genetic variation in Toll-like receptor (TLR) genes might be considered as molecular risk factors for NHL. The aim of the current study was to investigate the possible association between genetic polymorphism of the TLRs genes and B cell NHL (B-NHL) risk in Egypt. The present study included 100 B-NHL patients and 100 healthy controls. Genotyping of TLR2-1350 T/C and TLR9-1237 T/C were done by polymerase chain reaction restricted fragment length polymorphism (PCR-RFLP) technique. The frequency of TLR2-1350 T/C polymorphic genotypes in B-NHL patients was 18 % for the heteromutant genotype (TC) and 1 % for the homomutant (CC). There was no statistical difference in the distribution of TLR2-1350 T/C genotypes between B-NHL patients and controls. As for TLR9-1237 T/C, the frequency of the heteromutant genotype (TC) was 58 % and the homomutant genotype (CC) was 1 % in B-NHL patients. Calculated risk estimation revealed that TLR9-1237 (TC) heterotype conferred almost fourfold increased risk of B-NHL (odds ratio (OR) = 3.93, 95 % confidence interval (CI) = 2.16-7.14), and the risk was higher in patients with indolent subtypes (OR = 6.64, 95 %CI = 2.31-9.08). In conclusion, the study revealed that TLR9-1237 T/C polymorphism can be considered as molecular risk factor for B-NHL among Egyptians.Annals of Hematology 06/2014; 93(11). DOI:10.1007/s00277-014-2131-z · 2.40 Impact Factor