Association of TNFA promoter region haplotype in Behçet's Disease

Correlation of Tumor Necrosis Factor-α -308G>A Polymorphism with Susceptibility, Clinical Manifestations, and Severity in Behçet Syndrome: Evidences from an Italian Genetic Case-Control Study

To investigate the association between a functional drug-response tumor necrosis factor (TNF)α gene polymorphism (at the positions of -308; rs1800629; NG_007462.1:g.4682G>A) and both disease susceptibility and clinical manifestations in a cohort of 130 Italian patients with Behçet syndrome (BS). A group of 100 ethnically, age, and gender matched healthy controls (HC) was also recruited. Genotyping was performed using molecular (amplification and direct sequencing) and in silico methods. The genotype distribution of BS patients and HC underlined a lower percentage of wild-type GG genotype in BS patients versus HC (106/130 patients, 81.5% vs. 91/100 HC, 91%; p < 0.05), while the heterozygous genotype (GA) was identified in 24/130 patients (18.5%) versus 9/100 HC (9%) (p < 0.05). GA genotype was significantly associated with the disease (odds ratio = 2.29, 95% confidence interval 1.01-5.18). No significant association was recognized between the single nucleotide polymorphism (SNP) and the BS clinical manifestations, as well as with disease severity (Krause's index). We found statistically significant higher frequency of TNFα rs1800629 GA genotype in patients than in controls. No significant association was recognized between the polymorphism and the clinical parameters, as well as between the SNP and the disease severity. Our data need to be confirmed in larger cohort of patients and matched controls.

Tumor necrosis factor (TNF)-308, -1031, and angiotensin-converting enzyme (ACE) DD/II polymorphisms' role in Behcet's disease with and without uveitis: a meta-analysis

PURPOSE

There are conflicting results of studies investigating the association between the tumor necrosis factor (TNF) and angiotensin-converting enzyme (ACE) gene polymorphisms and Behcet's disease (BD). The aim of this meta-analysis is to assess the association between these gene polymorphisms and ocular involvement in BD.

METHODS

We identified relevant studies and reviewed the full-text manuscripts of the studies in order to select those for inclusion. Heterogeneity of studies was evaluated using Cochran Q-test and I-square index. To modify the heterogeneity in the variables we used random effects model. Meta-analysis was performed using STATA.

RESULTS

We analyzed TNF-1031, -308 and ACE DD/II genotype difference between BD patients with and without uveitis. Among these polymorphic genetic loci TNF-308 AA genotype has a statistically significant protective effect against BD uveitis (OR = 0.45 vs 1.23, p = .017). Such a statistically significant effect was not seen for other studied genotypes.

CONCLUSION

This meta-analysis revealed a significant protective effect of TNF-308 AA genotype against ocular involvement in Behcet's disease.

Overexpression of microRNA‑155 alleviates palmitate‑induced vascular endothelial cell injury in human umbilical vein endothelial cells by negatively regulating the Wnt signaling pathway

The present study aimed to investigate the effect of microRNA155 (miR-155) on palmitate-induced vascular endothelial cell injury in human umbilical vein endothelial cells (HUVECs) via the regulation of the Wnt signaling pathway. HUVECs were treated with 0.1 mM palmitate. After transfection with mimic, antagomir or the Wnt pathway inhibitor XAV939, HUVECs were divided into six treatment groups: Control, palmitate, mimic + palmitate, mimic + palmitate + XAV939, antagomir + palmitate, antagomir + palmitate + XAV939. miR-155 expression was detected using reverse transcription-quantitative PCR. The expression levels of the Wnt signaling pathway-related factors β-catenin and Cyclin D, and the inflammatory factors interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), were detected using western blot analysis. MTT and Transwell assays were used to detect the proliferation and migration of cells, respectively. Apoptosis and reactive oxygen species (ROS) levels were determined using flow cytometry. The localization of β-catenin in cells was determined by immunofluorescence. Palmitate reduced the expression level of miR-155 in HUVECs. In palmitate-induced HUVECs, overexpression of miR-155 promoted cell proliferation, reduced the levels of apoptosis, downregulated IL-6 and TNF-α expression, and reduced ROS levels. Inhibition of the Wnt signaling pathway enhanced the anti-endothelial cell injury effect caused by the overexpression of miR-155 in palmitate-induced HUVECs, thereby promoting proliferation, reducing apoptosis, downregulating the levels of inflammatory factors and reducing ROS levels. In summary, overexpression of miR-155 inhibited palmitate-induced apoptosis, ROS production and levels of inflammatory factors, and promoted the proliferation of HUVECs by negatively regulating the Wnt signaling pathway. This present study provides a theoretical basis for the prevention and treatment of cardiovascular diseases associated with endothelial cell injury.

UVEOGENE: An SNP database for investigations on genetic factors associated with uveitis and their relationship with other systemic autoimmune diseases

Uveitis is an intraocular inflammatory disease which can lead to serious visual impairment. Genetic factors have been shown to be involved in its development. However, few databases have focused on the information of associations between single nucleotide polymorphisms (SNPs) and uveitis. To discover the exact genetic background of uveitis, we developed an SNP database specific for uveitis, “UVEOGENE,” which includes 370 genes and 918 SNPs covering 14 uveitis entities and 40 populations from 286 PubMed English‐language papers. Stratification analyses by gender, HLA status, and different clinical features were also extracted from the publications. As a result, 371 associations were judged as “statistically significant.” These associations were also shared with Global Variome shared Leiden Open Variation Database (LOVD) (https://databases.lovd.nl/shared/genes). Based on these associations, we investigated the genetic relationship among three widely studied uveitis entities including Behcet's disease (BD), Vogt–Koyanagi–Harada (VKH) disease, and acute anterior uveitis (AAU). Furthermore, “UVEOGENE” can be used as a reliable and informative resource to identify similarities as well as differences in the genetic susceptibility among uveitis and other autoimmune diseases. UVEOGENE is freely accessible at http://www.uvogene.com.

Association of TNF-Alpha gene polymorphisms and susceptibility to hepatitis B virus infection in Egyptians

Tumor necrosis factor alpha (TNF-α) is one of the important cytokine in generating an immune response against hepatitis B virus (HBV). Genetic polymorphisms might influence gene transcription, leading to disturbance in cytokine production. We hypothesized that single nucleotide polymorphism (SNPs) in TNF-α gene could affect the pathogenesis of HBV. To test this hypothesis, we investigated the role of TNF-α polymorphism [-863C/A (rs1800630), -308G/A (rs1800629), -376G/A (rs1800750), -857C/T (rs1799724) and +489G/A (rs1800610)] in the susceptibility to chronic hepatitis B (CHB) infection. Polymorphisms of the TNF-α (-863C/A (rs1800630), -308G/A) were analyzed by Polymerase chain reaction sequence specific primer (PCR-SSP) while TNF-α (-376G/A, -857C/T and +489G/A) by PCR-restriction fragment length polymorphism (PCR-RFLP) in 104 patients with CHB and 104 healthy controls. The plasma level of TNF-α was measured using Enzyme-linked immunosorbent assay (ELISA). The study showed a significant increase in the frequency of -863CC, -376GA, -857CC, -857TT and +489GA genotypes and -863C, -376A, -857C, and +489A alleles in CHB patients compared to controls. In addition, CAGCG haplotype had a highest frequency in CHB patients. A strong Linkage Disequilibrium (LD) between TNF-α -863C/A (rs1800630) and -376G/A (D' = 0.7888, r² = 0.0200); -308G/A and -857C/T (D' = 0.9213, r² = 0.1770); -308G/A and +489G/A (D' = 0.9088, r² = 0.1576) was demonstrated. CHB patients had significantly lower levels of TNF-α compared to controls. In conclusion, our preliminary results suggest that -863C/A (rs1800630), -308G/A, -376G/A, and +489G/A of the TNF-α gene may play a role in HBV susceptibility in Egyptians. The significant reduction in TNF-α in CHB patient was independent of any particular genotype/haplotype in TNF-α.

Polymorphisms of Promoter Region of TNF-α Gene in Iranian Azeri Turkish Patients with Behçet's Disease

Behçet's disease (BD) is a complex chronic relapsing inflammatory disorder of unknown etiology. Alterations of the tumor necrosis factor (TNF) expression related to the polymorphic alleles of TNF gene may implicate a pathogenetic role in increased activity of this cytokine in BD. A current study aimed at investigating the possible association between BD and its clinical features in Iranian Azeri Turks with two functional TNF-α gene polymorphisms (at the positions of -238 and -857). A total number of 166 Iranian subjects were enrolled into two different groups; patients with BD (n = 64), and ethnically matched healthy controls (n = 101). The genotype distributions of BD patients and healthy controls were determined. The frequency of TNF-α -857C allele was significantly higher in Behçet's patients than that of healthy controls (P = 0.001; odds ratio [OR] = 2.616; 95% confidence interval [CI] = 1.129-6.160), whereas the frequency of TNF-α -238A allele was similar in both groups. The sole TNF-α haplotype-857C-1031C, was associated with an increase in the risk of developing BD. The TNF-α -857C allele was considerably associated with BD in this cohort. The findings of this study, collectively, indicate that TNF-α -857C-1031C haplotype located in the promoter region of the gene could exert major influence on the susceptibility to BD.

Inflammation-related cytokine gene polymorphisms in Behçet's disease

Behçet's disease (BD) is a complex, multisystemic inflammatory disorder of unclear etiology. Single nucleotide polymorphisms in tumor necrosis factor (TNF) and interleukin (IL)-10 genes have been implicated in susceptibility to BD with inconsistent results in several ethnic populations. The aim of this case-control study was to evaluate the association of TNF-α (-308G/A), TNF-β (+252A/G), and IL-10 (-1082G/A, -819C/T, and -592 C/A) polymorphisms with susceptibility of BD in Saudi patients. Molecular genotyping of TNF-α, TNF-β, and IL-10 gene polymorphisms was performed to analyze the alleles and genotypes distribution in 272 Saudi subjects, including BD patients (61) and healthy controls (211). The frequencies of allele A and genotype GA of TNF-α (-308G/A) were significantly higher, whereas those of allele G and genotypes GG were significantly lower in BD patients than controls, indicating that A allele and GA genotype are susceptible, while G allele and GG genotype may be refractory to BD. The distribution of frequencies of alleles and genotype of TNF-β (+252A/G) promoter polymorphism was not significantly different between BD patients and healthy controls. Genotypes 1082GG, -819TT, and 592AA of IL-10 polymorphisms are significantly associated with susceptibility risk of BD, while genotypes 1082AA, 1082GA, 819CC, 819CT, 592CC, and 592CA are resistant to BD. This study indicates that TNF-α (-308G/A) and IL-10 (-1082G/A, -819C/T, and -592C/A) polymorphisms are associated with risk of BD susceptibility in Saudi patients. However, larger scale studies in Saudi population as well as in other ethnicities are needed to confirm this association.

Association of tumor necrosis factor (TNF) promoter polymorphisms with plasma TNF-α levels and susceptibility to diabetic nephropathy in North Indian population

AIM

The concept of diabetic nephropathy (DN) as a metabolic disease is now being replaced by chronic low-grade inflammatory disease. Tumor necrosis factor-alpha (TNF-α) is a proinflammatory cytokine which plays an important role in the pathogenesis and clinical outcome of DN. Therefore, this work was planned to evaluate the association of -863C/A (rs1800630) and -1031T/C (rs1799964) polymorphisms in TNF gene with plasma TNF-α levels and DN among subjects with type 2 diabetes (T2DM) in a population from North India.

METHODS

Age and sex matched 100 healthy controls (HC), 100 T2DM subjects without nephropathy (DM) and 100 subjects with DN were screened for above polymorphisms using the PCR-RFLP methods. Plasma TNF-α levels were measured by ELISA. Analysis of variance and logistic regression were used to associate individual polymorphisms with plasma TNF-α levels and DN.

RESULTS

The allelic frequencies of -863C/A were 0.86/0.14 in HC, 0.72/0.23 in DM and 0.84/0.16 in DN, and that of -1031T/C were 0.89/0.11 in HC, 0.95/0.05 in DM and 0.80/0.20 in DN. The carriers of -863A allele had significantly lower plasma TNF-α levels (p<0.05). The -863C/A (OR=0.439, 95% CI=0.244-0.789, p=0.006) and -1031T/C (OR=3.0, 95% CI=1.355-6.642, p=0.007) were strongly associated with risk of development of DN.

CONCLUSIONS

-863C/A was associated with low whereas -1031T/C with high TNF-α levels. The, results suggest that -863C/A polymorphism might be protective whereas -1031T/C may be associated with increased risk for DN in subjects with T2DM from North India.

Immunopathogenesis of ocular Behçet's disease

Behçet's disease (BD) is a chronic recurrent systemic inflammatory disorder of unknown etiology characterized by oral and genital ulcerations, skin lesions, and uveitis. The ocular involvement of BD, or Behçet's uveitis (BU), is characterized by panuveitis or posterior uveitis with occlusive retinal vasculitis and tends to be more recurrent and sight threatening than other endogenous autoimmune uveitides, despite aggressive immunosuppression. Although pathogenesis of BD is unclear, researches have revealed that immunological aberrations may be the cornerstone of BD development. General hypothesis of BD pathogenesis is that inflammatory response is initiated by infectious agents or autoantigens in patients with predisposing genetic factors and perpetuated by both innate and acquired immunity. In addition, a network of immune mediators plays a substantial role in the inflammatory cascade. Recently, we found that the immunopathogenesis of BU is distinct from other autoimmune uveitides regarding intraocular effector cell profiles, maturation markers of dendritic cells, and the cytokine/chemokine environment. In addition, accumulating evidence indicates the involvement of Th17 cells in BD and BU. Recent studies on genetics and biologics therapies in refractory BU also support the immunological association with the pathogenesis of BU. In this review, we provide an overview of novel findings regarding the immunopathogenesis of BU.

Association Analysis of IL10, TNF-α, and IL23R-IL12RB2 SNPs with Behçet's Disease Risk in Western Algeria

Objective: We have conducted the first study of the association of interleukin (IL)-10, tumor necrosis factor alpha (TNF-α), and IL23R-IL12RB2 region single nucleotide polymorphisms (SNPs) with Behçet’s disease (BD) in Western Algeria.

Methods: A total of 51 BD patients and 96 unrelated controls from West region of Algeria were genotyped by direct sequencing for 11 SNPs including 2 SNPs from the IL10 promoter [c.-819T > C (rs1800871), c.-592A > C (rs1800872)], 6 SNPs from the TNF-α promoter [c.-1211T > C (rs1799964), c.-1043C > A (rs1800630), c.-1037C > T (rs1799724), c.-556G > A (rs1800750), c.-488G > A (rs1800629), and c.-418G > A (rs361525)], and 3 SNPs from the IL23R-IL12RB2 region [g.67747415A > C (rs12119179), g.67740092G > A (rs11209032), and g.67760140T > C (rs924080)].

Results: The minor alleles c.-819T and c.-592A were significantly associated with BD [odds ratio (OR) = 2.18; 95% confidence interval (CI) 1.28–3.73, p = 0.003]; whereas, there was weaker association between TNF-α promoter SNPs or IL23R-IL12RB2 region and disease risk.

Conclusion: Unlike the TNF-α and the IL23R-IL12RB2 region SNPs, the two IL10 SNPs were strongly associated with BD. The -819T, and -592A alleles and the -819TT, -819CT, and -592AA and -592CA genotypes seem to be highly involved in the risk of developing of BD in the population of Western Algeria.

Polymorphisms in the tumor necrosis factor gene and susceptibility to Behcet's disease: an updated meta-analysis

PURPOSE

Studies investigating the association between the tumor necrosis factor (TNF) gene polymorphisms and Behcet's disease (BD) report conflicting results. The aim of this meta-analysis was to assess the association between TNF gene polymorphisms and BD.

METHODS

A systematic literature search was conducted to identify all relevant studies. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to estimate the strength of the association.

RESULTS

A total of 16 articles, involving 1,708 patients with BD and 1,910 healthy controls, were included in the meta-analysis. Overall, a significant association was found between BD and the TNF -308A/G polymorphism (OR = 0.730, 95% CI = 0.608-0.877, p = 0.001). Meta-analysis of TNF -238A/G showed significant association with BD (OR = 1.512, 95% CI = 1.155-1.979, p = 0.003). The TNF -1031C allele showed significant association with BD (OR = 1.549, 95% CI = 1.190-2.015, p = 0.001). Similarly, the meta-analysis showed a significant association of the TNF -857T/C polymorphism with BD (OR = 0.758, 95% CI = 0.593-0.968, p = 0.027). Stratification by ethnicity revealed that the -308A/G and -857T/C polymorphisms were associated with BD in the Asian group, while the -238A/G and -1031C/T polymorphisms were associated with BD in the Caucasian population.

CONCLUSIONS

The results of our meta-analysis suggest that TNF (-308A/G, -238A/G, -1031C/T, and -857T/C) polymorphisms are associated with susceptibility to BD.

Distribution of the IL-1RN, IL-6, IL-10, INF-γ, and TNF-α Gene Polymorphisms in the Mexican Population

BACKGROUND

Cytokines are a group of polypeptides with an important role in the inflammatory response. It has been suggested that certain polymorphisms located in several cytokine genes are associated with different diseases. The aim of the present study was to establish the gene frequency of 13 polymorphisms of the IL-1RN, IL-6, IL-10, INF-γ, and TNF-α genes in a Mexican population. These polymorphisms have been reported in several populations, with important variation in frequency according to the studied population.

METHODS

Thirteen polymorphisms (rs419598, rs315951, rs2234663, rs3811058, rs1800796, rs2069827, rs1800896, rs1800871, rs1800872, rs1800629, rs2069709, rs2069710, and rs361525) were analyzed by 5' exonuclease TaqMan genotyping assays in a group of 248 healthy unrelated Mexican individuals.

RESULTS

The results obtained showed that the studied Mexican population presents significant differences (p<0.05) in the distribution of the IL1RN (rs419598, rs315951, and and rs2234663), IL1F10 (rs3811058), IL6 (rs1800796, rs2069827), IL10 (rs1800896, rs1800871, and rs1800872), and TNF-α (rs1800629) polymorphisms when compared to Caucasian, Asian, and African populations.

CONCLUSIONS

In summary, the distribution of the IL-1RN, IL-6, IL-10, and TNF-α cytokine gene polymorphisms distinguishes the studied Mexican population from other groups. Since the alleles of these cytokines are associated with the development of several inflammatory diseases, knowledge of the distribution of these alleles in the studied Mexican population could be helpful to understand their true role as a genetic susceptibility marker in this population.

New insights into the pathogenesis of Behçet's disease

Behçet's disease (BD) is a recurrent systemic inflammatory disorder of unknown origin characterized by oral and genital mucous ulcer, uveitis, and skin lesions. Involvement of large vessels, central nervous system (CNS), gastrointestinal tract and thrombotic events are less frequent but can be life threatening. The aim of this review is to provide new insights into the pathogenesis of BD. Over the past year substantial advances have been done in the understanding of the genetic [1,2] and immunology [3] of BD. BD is at the crossroad between autoimmune and autoinflammatory syndromes. In common with autoimmune diseases BD shares class I MHC association. However, in contrast to autoimmune disorders, BD has clinical features that seem to be mostly autoinflammatory. The pathogenesis of BD is still unknown, but major determinants of the genetic and immune system abnormalities have been reported recently. Triggering infectious factors are supposed to participate in the outbreak of BD in genetically predisposed patients. Two recent large genome-wide association study (GWAS) conducted in Turkey and Japan reported association between single nucleotide polymorphism (SNP) of interleukin (IL)-10 and IL-23R/IL-12RB2 genes and BD. New insights into the perturbations of T cell homeostasis of BD recently emerged. We have recently demonstrated the promotion of Th17 responses and the suppression of regulatory T cells (Tregs) that were driven by interleukin (IL)-21 production and that correlates with BD activity. Inflammatory cells within BD inflammatory lesions included mostly neutrophils, Th1 and Th17 cells, and cytotoxic CD8+ and γδ T cells. Altogether, the recent progresses in the knowledge of BD pathogenesis pave the way for innovative therapy.

Lack of an association of PD-1 and its ligand genes with Behcet's disease in a Chinese Han population

BACKGROUND

Behcet's disease is a chronic, multi-systemic autoimmune disease. Programmed cell death 1 (PD-1) gene is one of non-human leucocyte antigen genes. It has been demonstrated to be associated with several autoimmune diseases. However, only a few studies have addressed the association of ligand genes of PD-1, PD-L1 and PD-L2 with autoimmune disease. The purpose of this study was to analyze the potential association of the PD-1 and its ligand genes with Behcet's disease in a Chinese Han population.

METHODOLOGY/PRINCIPAL FINDINGS

Four single-nucleotide polymorphism (SNPs) rs2227981 and rs10204525 of PD-1, rs1970000 of PD-L1 and rs7854303 of PD-L2 were genotyped in 405 Behcet's patients and 414 age-, sex-, ethnic-matched healthy controls using polymerase chain reaction-restriction fragment length polymorphism assay. The results revealed that there were no significant differences in the genotype and allele frequencies of PD-1 rs2227981 and rs10204525 between the Behcet's patients and controls. A similar result was found for PD-L1 rs1970000 versus healthy controls. Only the C allele and the CC genotype of PD-L2 rs7854303 were identified in patients and controls. Stratification analysis based on gender and clinical findings did not show any associations between PD-1 or its ligand polymorphisms and Behcet's disease.

CONCLUSIONS/SIGNIFICANCE

None of the currently studied SNPs, PD-1 rs2227981 and rs10204525, PD-L1 rs1970000 and PD-L2 rs7854303, are associated with the susceptibility to Behcet's disease in a Chinese Han population. More studies are needed to confirm these findings in Behcet's patients with other ethnic backgrounds.

Genetic susceptibility to Behcet's disease: role of genes belonging to the MHC region

OBJECTIVE

To review the progress in the field of MHC-related genetic susceptibility to Behçet's disease (BD).

METHOD

Systematic review of the English literature between 1 January 1980 and 31 January 2010 using Medline. Case-control, population-based, observational cohort studies investigating the association between BD and HLA-B*51 subtypes, classical and non-classical HLA alleles and other HLA-related genes were selected. The geographical distribution of BD and these susceptibility genes was also taken into consideration. Case and familial case reports were excluded except for case series with more than two patients.

RESULTS

Ninety articles plus 17 obtained from other sources were included in the systematic review. We have found high evidence that a core component of genetic susceptibility to BD is within the MHC region being primarily related to an HLA-B*51 subtype: HLA-B*5101/B*510101. Moreover, HLA-A*26, HLA-B*15, HLA-B*5701 and TNF-α -1031C were independently associated with BD. Data suggest that other HLA (HLA-C, HLA-DR) and HLA-related [MHC Class I chain-related gene A (MIC-A), TNF-α] genes may play a role in BD co-susceptibility or pathogenesis. Finally, the distinctive geographical distribution of BD suggested an evolutionary selection of HLA-B*51 subtypes as the major susceptibility factors for BD.

CONCLUSION

Further studies must be addressed to clarify the functional relevance of the different genes found to be associated with disease susceptibility and the potential interactions between genes located within and outside the MHC region.

Association of tumor necrosis factor gene polymorphisms with susceptibility to dilated cardiomyopathy in a Han Chinese population

Tumor necrosis factor (TNF) is an immunomodulatory cytokine that plays an important role in many inflammatory and autoimmune diseases. We investigated the correlation between single-nucleotide polymorphisms of the TNF gene [i.e., TNF-α (308), TNF-α (857), TNF-α (863), TNF-α (1031), and TNF-ß (+252)] and dilated cardiomyopathy (DCM). A total of 110 DCM patients and 110 control subjects were genotyped using polymerase chain reaction-restriction fragment length polymorphism and DNA-sequencing assay. GA=AA genotypes of TNF-α (308) were significantly associated with increased risk of DCM compared with GG genotype (odds ratio[OR]=1.92; 95% confidence intervals [CI], 1.05-3.52). Similarly, GA=AA of TNF-ß (+252) was significantly associated with increased risk of DCM compared with GG genotype (OR=1.97; 95% CI, 1.14-3.38). Additionally, A allele of TNF-α (-308) and TNF-ß (+252) was associated with a 1.76-fold increased risk of DCM compared with G allele (OR=1.76; 95% CI, 1.05-2.95 and OR=1.79; 95% CI, 1.22-2.63, respectively). However,no association between DCM and TNF-α (857), TNF-α (1031), and TNF-α (863) was observed. TNF gene polymorphisms may be associated with risk of DCM.

Association of Pro/Anti-inflammatory Cytokine Gene Polymorphisms with Benign Prostate Hyperplasia Risk

Benign prostate hyperplasia (BPH) is a common condition in aged men and result from prolong chronic inflammation in prostate gland. Cytokines are important molecules responsible for inflammation. Single nucleotide polymorphisms (SNPs) in promoter region of cytokine genes have been shown to alter the level of cytokines. Hence we evaluated the association of pro-inflammatory and anti-inflammatory cytokine SNPs in a North Indian cohort of BPH patients. We observed that IL-1B -511 CT + TT genotypes conferred protective effect for susceptibility to BPH (OR 0.39, P 0.001). Our results also demonstrated that TNF-A -1031 C allele to be associated with risk for BPH (OR 1.89, P < 0.0001). Moreover, we also observed twofold risk for IL-10 -1082 cytokine gene polymorphism (OR 1.96, P 0.048). No association was observed with risk of BPH for IFN-G +874, IL-1 RN VNTR, IL-6 -174, IL-10 -819 and TGF-B +28. Our findings of IL-1B -511, TNF-A -1031 and IL-10 -1082 suggested that these variants play important role in susceptibility to BPH. Future studies in large cohort of different ethnicity BPH groups are warranted to establish definite associations with other cytokine gene polymorphisms as well.

TNF polymorphisms in patients with Behçet disease: a meta-analysis

BACKGROUND AND AIMS

Polymorphisms in the tumor necrosis factor (TNF) gene at the locations -308, -238, -863, -857 and -1031 have been studied in various ethnic groups for possible association with Behçet's disease. The aim of this meta-analysis is to examine the association between polymorphism in the TNF gene at the locations -308, -238, -863, -857 and -1031 and Behçet's disease.

METHODS

A literature review was performed using MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials for original studies published in English up to October 31, 2009 and that examined the association of the TNF-alpha promoter polymorphisms with Behçet's disease. All pooled odds ratios (OR) were derived from random-effects model with its 95% confidence intervals (CI). We assessed statistical heterogeneity among studies using Cochrane Q test and by calculating I(2). The Cochrane collaboration's software program, RevMan 5 was used to prepare and complete this review.

RESULTS

The literature search resulted in 13 studies. Ten studies met the included criteria and thus were selected. Overall, -1031C (OR = 1.35, 95% CI = 1.09-1.68), -238A (OR = 1.51, 95% CI = 1.12-2.04) and -857T (OR = 0.76, 95% CI = 0.58-0.98) had a significant association with Behcet's disease. The pooled estimates for the other polymorphisms were not statistically significantly associated with Behcet's disease; -308A and -863A.

CONCLUSIONS

Behcet's disease was associated with the -1031C, -238A and the -857T promoter polymorphisms in various ethnic groups.

Polymorphisms in tumor necrosis factor-A gene and prostate cancer risk in North Indian cohort

PURPOSE

The proinflammatory cytokine tumor necrosis factor-alpha has an important role in the pathogenesis of prostate cancer. Single nucleotide polymorphisms in the promoter region of the TNF-A gene alter tumor necrosis factor-alpha transcription. Thus, we studied the association of 4 SNPs in the promoter region of TNF-A gene, including -1031T>C, -863C>A, -857 C>T and -308 G>A, in a North Indian cohort of patients with prostate cancer.

MATERIALS AND METHODS

The study involved 453 subjects. All 197 case and 256 control samples were genotyped for the 4 promoter polymorphisms in the TNF-A gene using allele specific polymerase chain reaction and polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

Results showed an increased risk of prostate cancer for the TNF-A -1031 CC genotype (OR 2.01, p = 0.03). No significant association was observed for the TNF-A -863 C>A, TNF-A -857 C>T or -308 G>A polymorphisms. Haplotype analysis revealed that TNF-A -1031C-863C-857T-308G was significantly associated with prostate cancer risk (OR 2.22, p = 0.013). Moreover, the TNF-A -1031 C and -857 T alleles were associated with higher tumor grade and an increased risk of tumor progression and metastasis.

CONCLUSIONS

These results show that TNF-A polymorphisms have an important role in prostate cancer pathogenesis. Results are in line with findings in other studies from the West and to our knowledge for the first time from India indicating the involvement of immune system genes in prostate cancer pathogenesis.

Immune response genes in uveitis

Uveitis is defined as an intraocular inflammation induced by different etiologies. Though the precise pathogenesis is still unknown, accumulating evidence shows that both innate and adaptive immune responses may be predominant mechanisms involved in the development of uveitis. Toll-like receptors have been shown to be expressed in the human eye and play an important role in infectious uveitis. The NOD proteins, expressed mainly in the cytosol by APCs, recognize the products of bacteria and participate in the development of uveitis. HLA genes have been associated with some uveitis entities, including acute anterior uveitis (HLA-B27), Behcet disease (HLA-B51), birdshot retinochoroidopathy (HLA-A29), Vogt-Koyanagi-Harada syndrome (HLA-DR4), sarcoidosis, sympathetic ophthalmia, juvenile idiopathic arthritis, tubulointerstitial nephritis and uveitis (TINU) syndrome, and pars planitis (HLA-DR15). The exact mechanism whereby certain HLA genes predispose to a certain uveitis entity has not yet been elucidated. In addition, several studies have demonstrate that polymorphisms in certain immune response genes, such as tumor necrosis factor (TNF), MHC class I polypeptide-related sequence A (MICA), interleukin-1 (IL-1), and some chemokines, may contribute to the development of human uveitis. Polymorphisms in the gene coding for the costimulatory molecule known as cytotoxic T-lymphocyte antigen 4 (CTLA-4) were recently found in Chinese patients with VKH syndrome but not in patients with Behcet disease. Further developments in the unraveling of immune response genes may lead to a better understanding of human uveitis and will hopefully allow the development of novel treatment regimes.

Immunogenetics of drug-induced skin blistering disorders. Part II: Synthesis

The overall immunopathogenesis relevant to a large series of disorders caused by a drug or its associated hyperimmune condition is discussed based upon examining the genetics of severe drug-induced bullous skin problems (sporadic idiosyncratic adverse events including Stevens–Johnson syndrome and Toxic epidermal necrolysis). New results from an exemplar study on shared precipitating and perpetuating inner causes with other related disease phenotypes including aphtous stomatitis, Behçets, erythema multiforme, Hashimoto’s thyroiditis, pemphigus, periodic fevers, Sweet’s syndrome and drug-induced multisystem hypersensitivity are presented. A call for a collaborative, wider demographic profiling and deeper immunotyping in suggested future work is made.

Role of TNF-alpha gene variation in idiopathic childhood ischemic stroke: a case-control study

Etiology of the idiopathic childhood stroke remains unknown. In previous studies, the immunologic process may be involved in the idiopathic stroke. Tumor necrosis factor- alpha (TNF-alpha), an important immune mediator, may contribute to the initiation and progression in the stroke. The main purpose of this study was to investigate correlation of TNF-alpha genetic variation and idiopathic childhood ischemic stroke. Using the direct DNA sequencing method, polymorphisms in the TNF-alpha promoter region were genotyped in 67 Chinese patients with idiopathic childhood stroke and 70 controls. Among totally 7 single nucleotide polymorphisms identified in the TNF-alpha promoter region, the variant of the -863C/A is associated with increased risk of idiopathic childhood ischemic stroke in our study group. TNF-alpha molecule may have genetically as well as functionally an important role in the pathogenesis of idiopathic childhood ischemic stroke in the Chinese population.

Association between polymorphisms of FCRL3, a non-HLA gene, and Behçet's disease in a Chinese population with ophthalmic manifestations

PURPOSE

Studies have shown a strong association of human leukocyte antigens-B51 (HLA-B51) with Behçet's disease (BD). However, little is known about the association of non-HLA genes with BD. The polymorphisms of the Fc receptor-like 3 gene (FCRL3), -169C/T, -110A/G, +358C/G, and +1381A/G, have been reported to be associated with several autoimmune diseases. This study was designed to determine whether the polymorphisms of FCRL3 were associated with susceptibility to BD in a Chinese population mainly with ocular involvement.

METHODS

A case-control study was performed in 245 Chinese BD patients and 289 controls. Four single nucleotide polymorphisms (SNPs; -169C/T, -110A/G, +358C/G, and +1381A/G) in FCRL3 were detected using polymerase chain reaction restriction fragment length polymorphisms (PCR-RFLP). HLA-B51 genotyping was performed by the PCR sequence specific primers method as described previously.

RESULTS

The results showed a significantly higher frequency of the G allele at the -110 site in BD patients compared with that in controls (corrected p=0.044, 75.3% versus 67.5%, chi2=7.72). Haplotype CGCG frequency was significantly higher in patients than in controls (corrected p=0.0096) whereas haplotype TACG frequency was significantly lower in patients compared with controls (corrected p=0.032). There was no relationship between clinical signs and FCRL3 polymorphisms. No significant difference was observed between patients and controls after HLA-B51 stratification concerning the four SNPs.

CONCLUSIONS

Our study suggests that the -110 G allele and the haplotype CGCG of FCRL3 are positively associated with BD in a Chinese population and that the haplotype ATCG might be a protective haplotype for BD.

Interleukin-17F gene polymorphisms in Korean patients with Behçet's disease

IL-17 is a novel cytokine that is characterized by an ability to induce several types of cells to secrete proinflammatory cytokines in various inflammatory diseases. This study analyzed the influence of IL-17F gene polymorphisms on disease susceptibility and clinical features. Ninety-nine Behçet's disease (BD) patients and 114 controls were genotyped to analyze three single nucleotide polymorphisms (SNPs) including A126G, G155A, and A161G of the IL-17F gene using automated sequencing. We compared the frequencies of IL-17F alleles, genotypes, and haplotypes in patients with BD and controls using the chi-square or Fisher's exact test. Significant differences in the frequencies of allele and genotype in A126G SNP of IL-17 gene were found between BD patients and controls (P<0.001 and P<0.001, respectively). None of three IL-17F SNPs were associated with diverse clinical features in BD. The frequency of haplotype AA did not differ between patients with BD and controls (P=0.985). The haplotypes, AG, and GG, have positive and inverse association with BD susceptibility (P<0.001 and P<0.001, respectively). These findings suggest that IL-17 gene SNPs may influence the susceptibility of BD.

TNF promoter polymorphisms associated with muscle phenotypes in humans

Tumor necrosis factor-alpha (TNF-alpha) is a potent catabolic factor to skeletal muscle. Single-nucleotide polymorphisms (SNPs) in the promoter region of the TNF-alpha coding gene, TNF, have been implicated in the interindividual variation in TNF-alpha production via transcriptional regulation. The present study investigated the association of muscle phenotypes with five TNF promoter SNPs, which potentially have biological significance. Female and male volunteers (n = 1,050) from the Baltimore Longitudinal Study of Aging were genotyped, and their regional and total body muscle mass, and arm and leg muscle strength were measured. Results indicated that putative high-expression alleles at positions -1031 and -863, individually or in combination in the haplotype 1031C-863A-857C-308G-238G, were associated with lower muscle mass in men. Specifically, carriers of -1031C, compared with noncarriers, exhibited lower arm muscle mass (6.4 +/- 0.1 vs. 6.8 +/- 0.1 kg, P = 0.01) and appendicular skeletal muscle mass (ASM) (24.3 +/- 0.4 vs. 25.4 +/- 0.2 kg, P = 0.02), with leg muscle mass and the ASM index (ASMI; kg/m(2)) also tending to be lower (P = 0.06 and 0.07). Similarly, -863A allele carriers (linked with -1031), compared with noncarriers, exhibited lower arm muscle mass (6.4 +/- 0.1 vs. 6.8 +/- 0.1 kg, P = 0.04). Carriers of the haplotype 1031C-863A-857C-308G-238G, compared with noncarriers, exhibited lower arm muscle mass (6.3 +/- 0.2 vs. 6.8 +/- 0.1 kg, P < 0.01), trunk muscle mass (25.7 +/- 0.5 vs. 26.9 +/- 0.3 kg, P < 0.05), and ASM (24.1 +/- 0.5 vs. 25.3 +/- 0.2 kg, P < 0.025), with tendencies for lower leg muscle mass and ASMI (P = 0.07 and 0.08). Results indicate that genetic variation in the TNF locus may contribute to the interindividual variation in muscle phenotypes in men.

Cytokine genotype suggests a role for inflammation in nucleoside analog-associated sensory neuropathy (NRTI-SN) and predicts an individual's NRTI-SN risk

Nucleoside analog-associated sensory neuropathy (NRTI-SN) attributed to stavudine, didanosine, or zalcitabine (the dNRTIs) and distal sensory polyneuropathy (DSP) attributed to HIV are clinically indistinguishable. As inflammatory cytokines are involved in DSP, we addressed a role for inflammation in NRTI-SN by determining the alleles of immune-related genes carried by patients with and without NRTI-SN. Demographic details associated with risk of various neuropathies were included in the analysis. Alleles of 14 polymorphisms in 10 genes were determined in Australian HIV patients with definite NRTI-SN (symptom onset <6 months after first dNRTI exposure, n = 16), NRTI-SN-resistant patients (no neuropathy despite >6 months on dNRTIs, n = 20), patients with late onset NRTI-SN (neuropathy onset after >6 months of dNRTIs, n = 19), and HIV-negative controls. Carriage of TNFA-1031*2 was highest in NRTI-SN patients, suggesting potentiation of NRTI-SN. Carriage of IL12B (3' UTR)*2 was higher in NRTI-SN-resistant patients than controls or NRTI-SN patients, suggesting a protective role. BAT1 (intron 10)*2 was more common in NRTI-SN than resistant patients, but neither group differed from controls. This marks the conserved HLA-A1, B8, DR3 haplotype. Of the demographic details considered, increasing height was associated with NRTI-SN risk. A model including cytokine genotype and height predicted NRTI-SN status (p < 0.0001, R(2) = 0.54). Late onset NRTI-SN patients clustered genetically with NRTI-SN-resistant patients, so these patients may be genetically "protected." In addition to patient height, cytokine genotype influenced NRTI-SN risk following dNRTI exposure, suggesting inflammation contributes to NRTI-SN.