Fas and microRNAs Variations as a Possible Risk for Behçet Disease.

BACKGROUND: Behçet disease (BD) belongs to a disease family that has a transparent borderline between autoinflammatory and autoimmune disorders. Fas and some miRNAs have revealed to display remarkable roles in both autoimmune and autoinflammatory processes, and they can play important roles in defective apoptosis in BD. We investigated the association of the susceptibility of BD with Fas, miRNA variations, and their both single and combined presence in a Turkish population as a case-control study. METHODS: The distributions of FAS-670 A>G rs1800682, mir146a rs2910164, and mir196a rs11614913 polymorphisms are analyzed with the polymerase chain reaction-restriction fragment length polymorphism method in 115 BD patients and 220 controls in 6-month period. RESULTS: Statistical analysis indicates that in the case of Fas-670 A/G rs1800682, AA genotype and A allele have a protective role in BD (p = 0.0004 and p = 0.0009, respectively). The dominant model (AA + AG/GG) also displays a protective effect on BD unlike the recessive model (p = 0.03). In addition, both homozygous genotype (CC) of rs2910164 of mir-146a (p = 0.04) and the dominant model (CC + CG vs. GG) have protective effects on BD unlike the recessive model (p < 0.0001). Both mir-196a2 rs1800682 polymorphism and combined genotype analysis of rs1800682-rs2910164 and rs1800682-rs11614913 gave no statistically significant differences within the groups for genotypes and either of the alleles (p > 0.05). CONCLUSIONS: These findings indicate that both Fas rs1800682 and mir-146a rs2910164 variants might be important factors participating in the protection against BD in the Turkish population.

Variations in Toll-like receptor and nuclear factor-kappa B genes and the risk of glioma.

PURPOSE: Glioblastoma (GBM) is the most aggressive primary brain tumour in the adult nervous system and is associated with a poor prognosis. NF-KB activation is an important driver of the malignant phenotype that confers a negative prognosis in patients with GBM. NF-KB plays a role in Toll-like Receptors (TLR)-induced tumourigenesis. The aim of the present study was to investigate the association of a promoter region polymorphism of NFKB1 gene encoding the p50 subunit of NF-KB, namely -94ins/del ATTG, the most widely discussed the TLR2 Arg753Gln, TLR4Asp299Gly and TLR4Thr399Ile polymorphisms, their combined effects, and the glioma risk. METHODS: A group of 120 Glioma patients and 225 control subjects were screened for these four polymorphisms using the PCR-RFLP method. RESULTS: Statistical analysis indicates that the ins/ins genotype of NFKB -94ins/delATTG (p=0.003), and the AA genotype of TLR4Asp299Gly (p < 0.001) are risk factors for glioma and people carrying the ins allele have an approximately 1.47 times susceptibility risk of glioma whereas GG genotype of TLR2Arg753Gln seems to be protective against glioma (p = 0.002). Combined genotype analysis showed that del/ins-GG genotype of TLR2Arg753Gln-NFKB1, del/ins + GG genotype of TLR4Asp299Gly-NFKB1, del/ins-CC genotype of TLR4Thr399Ile-NFKB1 were risk factors for glioma development. CONCLUSION: NFKB1 -94ins/delATTG and TLR4Asp299Gly polymorphisms are associated with increased glioma cancer risk in a Turkish population.

Rheumatoid arthritis risk associates with DNA repair gene XRCC1 Arg399Gln polymorphism in Turkish patients.

Rheumatoid arthritis (RA) is an autoinflammatory disease with a genetic background. The synoviocytes in RA shows cellular transformation with tumor-like features, and RA patients have genomic instability and relaxation of DNA repair mechanisms. The polymorphisms in BER repair pathway genes, XRCC1 and OGG1, may change the response to inflammation via altered DNA repair capacity. In this study, we aimed to investigate the relationship between the risk of RA and XRCC1 Arg194Trp, Arg399Gln, and OGG1 Ser326Cys polymorphisms in a group of Turkish RA patients. XRCC1 Arg194Trp, Arg399Gln, and OGG1 Ser326Cys polymorphisms were investigated by PCR-RFLP method in 100 RA patients and 158 healthy control subjects. The results were statistically analyzed by calculating the odds ratios (OR) and their 95% confidence intervals (95% CI) using the χ(2)-tests. RA patients in this study had significantly higher frequencies of XRCC1 Arg399Gln polymorphism in both homozygote (GG) (35%, OR: 7.78 [95% CI: 3.65-16.59], P < 0.001) and heterozygote (AG) forms (41%, OR: 2.17 [95% CI: 1.19-3.96], P < 0.01) and also increased frequency of 399Gln (G) allele (55%, OR:2.99 [95% CI: 1.67-5.37], P < 0.001). We conclude that XRCC1 Arg194Trp, and OGG1 Ser326Cys polymorphisms are not associated with RA; however, Arg399Gln polymorphism is a significant risk factor of RA, and carriers of 399Gln (G) allele have greater risk of RA.

Metformin reverses the effects of high glucose on human dermal fibroblasts of aged skin via downregulating RELA/p65 expression.

Metformin has been successfully used as an anti-aging agent but exact molecular mechanisms of metformin in anti-aging remain unknown. Hyperglycemia during skin aging not only causes oxidative damage to cellular macromolecules, like dermal collagen, but also modulates the activation of transcription factor nuclear factor kappa B (NF-kB). We aimed to investigate in vitro effects of high glucose (HG) and metformin treatment on proliferation and apoptosis of human primary dermal fibroblasts (HDFs), and the expression of COL1A1, COL3A1, and RELA/p65 genes. Effects of normal glucose (5.5 mM) and HG concentration (50 mM HG) on HDFs, with two doses of metformin (50 µM and 500 µM), were investigated by immunostaining. Apoptotic levels were analyzed by flow cytometry. Expression of COL1A1, COL3A1, and RELA/p65 genes was measured by quantitative real-time PCR. The proliferation of HDFs was decreased significantly (P < 0.01) and expression of COL1A1 was downregulated by HG without metformin, whereas proliferation was elevated and expression was upregulated with 500 µM metformin + HG compared to 5.5 mM glucose (P < 0.05). The expression of COL3A1 and RELA/p65 were upregulated (P < 0.01 for COL3A1), and percentage of late apoptotic cells increased significantly by HG without metformin (P < 0.001) while it decreased in two concentrations of metformin dramatically compared with 5.5 mM glucose (P < 0.01 for expressions and < 0.001 for apoptosis). Metformin not only significantly downregulated RELA/p65 expression, but also inhibited the apoptosis of HDFs from aged human skin at toxic glucose concentrations which could be inversely mediated via COL1A1 and COL3A1 expression.

Association of NFKB1A and microRNAs variations and the susceptibility to atherosclerosis.

Atherosclerosis (AT) is a chronic immuno-inflammatory disease characterized by inflammatory mediators and immune activation in arterial wall. Although NF-κB and microRNAs are involved in the atherosclerotic lesions, the pathogenesis of atherosclerosis is still unknown. The aim of this study was to investigate the association of atherosclerosis with NFKB1-rs28362491, NFKBIA-rs696, pre-miRNA-146a-rs2910164 and pre-miRNA-499-rs3746444 polymorphisms as well as the analysis of their single and combined effects on its susceptibility in a Turkish population. We analysed the distribution of NFKB1-94 ins/del ATTG (rs28362491), NFKBIA (rs696), pre-miR-146a (rs2910164) and pre-miR-499 (rs3746444) genetic polymorphisms using PCR-RFLP assay in 150 atherosclerotic patients and 145 healthy controls in a Turkish population. The data revealed no significant differences in the distribution of the genotype and alleles of rs28362491 ,whereas AA genotype of rs696 lead to a higher risk for atherosclerotic patients. TT genotype and T allele of pre-miR-499 rs3746444 were found to be associated with atherosclerosis risk. In addition, significant differences were found between atherosclerotic patients and control subjects, concerning pre-miR-146a rs2910164 polymorphism. The subjects carrying the GG genotype and G allele of rs2910164 were found to have an increased risk against AT. The results of combined genotype analysis, showed no notable differences between the multiple comparisons of rs28362491- rs696 whereas rs28362491-rs2910164 ins/ins/GG is associated with increased AT risk. The combined genotypes of rs28362491/rs3746444 ins/ins/TT, revealed a significant protective effect on AT. These findings indicate that genetic polymorphisms of NFKB1A rs696, pre-miR-146a rs2910164 and pre-miR-499 rs3746444 may represent novel markers of AT susceptibility.

Association of Pre-miRNA-499 rs3746444 and Pre-miRNA-146a rs2910164 Polymorphisms and Susceptibility to Behcet's Disease.

MiRNAs and NFKB1 are well-known immune response and inflammation regulators. MiRNA gene polymorphisms may affect miRNA biogenesis and function and, may thus, lead to changes in the expression of hundreds of genes such as NFKB1. The aim of this study was to investigate the association of Behcet's disease (BD) with NFKB1 rs28362491, pre-miRNA-146a rs2910164, and pre-miRNA-499 rs3746444 polymorphisms, as well as the analysis of their single and combined effects on its susceptibility in a Turkish population. These polymorphisms were analyzed by using the polymerase chain reaction-restriction fragment length polymorphism method in 100 BD patients and 145 healthy control subjects. The results were analyzed statistically using Pearson chi-square (χ(2)) test and Fisher's exact test (two sided). According to genotype analysis, the frequencies of ins/ins genotype and ins allele of rs28362491 were considerably higher in BD patients. Also, miRNA-499 rs3746444 homozygous (TT) genotypes exibited a significantly higher risk in patients with BD (odds ratios [OR]=3.0, 95% confidence intervals [95% CI]=1.284-7.007, p=0.017). Moreover, the frequency of T allele of rs3746444 was a risk factor for BD (OR=1.562, 95% CI=1.087-2.24, p=0.015). In addition, significant differences were found between the groups concerning miRNA-146a rs2910164 polymorphism. Homozygous CC genotype and C allele of rs2910164 polymorphism were found to be protective factors against BD. The results of the combined genotype analysis showed no notable differences between the multiple comparisons of rs28362491-rs2910164 and of rs28362491-rs3746444 in patients and control groups. Our data demonstrate that homozygous CC genotype and C allele of rs2910164 polymorphism are protective factors against BD, but rs3746444 and rs28362491 polymorphisms in miRNA-499 and in NFKB1 promoter are involved in the genetic susceptibility of BD. In addition, TT and ins/ins genotypes may influence certain proinflammatory cytokines and, may thus, play a role in the pathogenesis of BD.

Polymorphism of the NFKB1 affects the serum inflammatory levels of IL-6 in Hashimoto thyroiditis in a Turkish population.

Hashimoto thyroiditis (HT) is a chronic inflammatory autoimmune disease of thyroid gland affected by interaction of multiple genes and various cytokines. Variants in the genes coding for the NFKB and IKB proteins can be potentially involved in the development of the inflammatory diseases. NFKB, a key transcription factor of the regulation of immune responses, is interesting candidate for association studies about autoimmune disorder. The aim of the present study was to investigate the relationship between NFKB1 and NFKBIA (NFKB1 inhibitor gene) polymorphisms, and the risk of HT in a Turkish Population in the context of IL-6 serum levels which may contribute to susceptibility to the disease. We analyzed the distribution of NFKB1-94ins/del ATTG and NFKBIA 3'UTR A→G polymorphisms using PCR-RFLP method and IL-6 serum levels using ELISA method in 120 HT patients and 190 healthy controls in Turkish population. Although, there was no statistical significant difference in distribution of the genotypes and alleles of NFKB1-94ins/del ATTG or NFKBIA 3'UTR A→G polymorphisms in patients and control subjects as single, ins/ins/GG combined genotype had protective effect on the disease when compared to ins/ins/AG combined genotype as combined genotypes of both polymorphisms. In addition to this finding, IL-6 serum levels in HT patients with del/del genotype were significantly higher than in patients with del/ins genotype (p<0.001). According to the combined genotype analysis of NFKB1-94ins/del ATTG and NFKBIA 3'UTR A→G polymorphisms, IL-6 levels were also higher in patients with del/del genotype when at least one G allele existing (p=0.007). Therefore, our findings suggest that the functional promoter NFKB1-94ins/del ATTG polymorphism was significantly associated with population HT disease through acting by directly modulating IL-6 serum levels.

Association of PARP-1, NF-κB, NF-κBIA and IL-6, IL-1ß and TNF-α with Graves Disease and Graves Ophthalmopathy.

BACKGROUND: Graves Disease (GD) is an autoimmune disorder affected by an interaction of multiple genes such as Nuclear Factor-κB (NF-κB), Nuclear Factor-κB Inhibitor (NF-κBIA), Poly (ADP-ribose) polymerase-1 (PARP-1) and cytokines like Interleukin-1ß (IL-1ß), Interleukin-6 (IL-6) and Tumor Necrosis Factor-α (TNF-α) and mostly accompanied by an ocular disorder, Graves Ophthalmopathy (GO). We hypothesize that there is a relationship between GD, GO, polymorphisms of inflammatory related genes and their association with cytokines, which may play important roles in autoimmune and inflammatory processes. SUBJECTS AND METHODS: To confirm our hypothesis, we studied the polymorphisms and cytokine levels of 120 patients with GD and GO using PCR-RFLP and ELISA methods, respectively. RESULTS: We found that patients with GG genotype and carriers of G allele of PARP-1 G1672A polymorphism are at risk in the group having GD (p=0.0007) while having GA genotype may be protective against the disease. PARP-1 C410T polymorphism was found to be associated with GO by increasing the risk by 1.7 times (p=0.004). Another risk factor for development of GO was the polymorphism of del/ins of NFkB1 gene (p=0.032) that increases the risk by 39%. Levels of cytokines were also elevated in patients with GD, but no association was found between levels of cytokines and the development of GO as there was no change in levels of cytokines. CONCLUSIONS: We suggest that, PARP-1 and NFkB1 gene polymorphisms may be risk factors for developing Graves Disease and Ophthalmopathy.

Association of three SNPs in the PARP-1 gene with Hashimoto's thyroiditis.

Poly(ADP-ribose) polymerase-1 (PARP-1) has a vital role in the progression of the inflammatory response, and its inhibition confers protection in various models of inflammatory disorders. Therefore, we investigated the effect of promoter and exon variations of the PARP-1 gene on the risk for the inflammatory disease Hashimoto's thyroiditis (HT). This case-control association study was comprised of 141 HT patients and 150 controls from a group of women in a Turkish population. Two polymorphisms in the promoter region of the PARP-1 gene, rs2793378 and rs7527192, were analyzed using the PCR-RFLP method. In addition, single nucleotide polymorphism (SNP) rs1136410, which is located at codon 762, was analyzed using bidirectional sequencing. The combined genotype and haplotype analyses of these polymorphisms were performed using SPSS 18 and Haploview 4.2. The results were statistically analyzed by calculating the odds ratios and 95% confidence interval using Pearson's χ (2)-test and Fisher's exact test (two-sided). Although we had a number of significant results, the associations became nonsignificant following a Bonferroni correction for multiple comparisons. Nonetheless, a protective factor against HT was still observed for the heterozygous genotype (TC) of SNP rs1136410 (P=0.001), even following Bonferroni correction, and according to the rs2793378-rs7527192 combined analysis, the occurrence of the TT/GA combined genotype was significantly higher in the controls (P=0.007). These results prove that the heterozygosity of SNP rs1136410 provides a protective effect against HT disease in a group of women in a Turkish population.