Role of the NFKB1 -94ins/delATTG promoter polymorphism in IBD and potential interactions with polymorphisms in the CARD15/NOD2, IKBL, and IL-1RN genes

Mendelian randomization study for the roles of IL-18 and IL-1 receptor antagonist in the development of inflammatory bowel disease

BACKGROUND AND AIMS

IL-1 and IL-18 play important roles in intestine barrier integrity maintenance and inflammatory response. However, their net effects on the risk of IBD are still inconclusive. Here, we used Mendelian randomization (MR) approaches to investigate the causal associations of IL-18 and IL-1Ra (receptor antagonist) on the risks of IBD and subtypes.

METHODS

For IL-18, both three-sample and two-sample MR approaches were used for the causal inferences. In three-sample MR, three single nucleotide polymorphisms (SNPs) and the effect values were extracted from two quantitative trait loci (pQTL) datasets with non-overlapping populations. In two-sample MR, we extracted genetic instruments information from the same larger pQTL dataset. For IL-1Ra, we applied the two-sample MR method with summary-statistics from the larger pQTL dataset. Summary-level results of three large IBD/CD/UC genome-wide association studies in European ancestry were employed. Inverse-variance weighted method, various sensitivity analyses and meta-analysis were performed to give causal estimates, detect heterogeneity and correct for outliers.

RESULTS

We observed consistent positive causal effects of IL-18 on all three major outcomes using three-sample MR, with meta-analyses odds ratios (ORs) equal to 1.240 (IBD), 1.199 (CD) and 1.274 (UC) respectively. The two-sample MR demonstrated similar results. Moreover, genetically predicted IL-1Ra is inversely associated with the risk of IBD/UC/CD with ORs equal to 0.915 (IBD), 0.902 (CD) and 0.899 (UC) respectively in meta-analyses.

CONCLUSIONS

This study suggested genetically predicted IL-18 and IL-1Ra level are causally associated with an increased and decreased risk of IBD and subtypes.

NF-κB signaling in inflammation and cancer

Since nuclear factor of κ-light chain of enhancer-activated B cells (NF-κB) was discovered in 1986, extraordinary efforts have been made to understand the function and regulating mechanism of NF-κB for 35 years, which lead to significant progress. Meanwhile, the molecular mechanisms regulating NF-κB activation have also been illuminated, the cascades of signaling events leading to NF-κB activity and key components of the NF-κB pathway are also identified. It has been suggested NF-κB plays an important role in human diseases, especially inflammation-related diseases. These studies make the NF-κB an attractive target for disease treatment. This review aims to summarize the knowledge of the family members of NF-κB, as well as the basic mechanisms of NF-κB signaling pathway activation. We will also review the effects of dysregulated NF-κB on inflammation, tumorigenesis, and tumor microenvironment. The progression of the translational study and drug development targeting NF-κB for inflammatory diseases and cancer treatment and the potential obstacles will be discussed. Further investigations on the precise functions of NF-κB in the physiological and pathological settings and underlying mechanisms are in the urgent need to develop drugs targeting NF-κB for inflammatory diseases and cancer treatment, with minimal side effects.

Polymorphisms in oxidative pathway related genes and susceptibility to inflammatory bowel disease

AIM

To investigate whether common variants in the oxidative pathway genes influence inflammatory bowel disease (IBD) risk among Moroccan patients.

METHODS

The distribution of (TAAA)n_rs12720460 and (CCTTT)n _rs3833912 NOS2A microsatellite repeats, HIF-1A_rs11549467 and NFKB1-94ins/delATTG_rs28362491 was analyzed in 507 subjects grouped in 199 IBD and 308 healthy controls. Genotyping was performed with polymerase chain reaction-fluorescent method and the TaqMan^® allelic discrimination technology.

RESULTS

The allele and genotype frequencies of HIF1A_ rs11549467, NFKB1_rs28362491 and NOS2A_ (TAAA)n did not differ significantly between patients and controls. Analysis of NOS2A_ (CCTTT)n markers evidenced differences between patients and healthy controls. A preferential presence of the (CCTTT)8 (P = 0.02; OR = 1.71, 95%CI: 1.07-2.74), (CCTTT)14 (P = 0.02; OR = 1.71, 95%CI: 1.06-2.76) alleles in IBD, (CCTTT)8 (P = 0.008; OR = 1.95, 95%CI: 1.17-3.23) in CD and (CCTTT)7 (P = 0.009; OR = 7.61, 95%CI: 1.25-46.08), (CCTTT)11 (P = 0.05; OR = 0.51, 95%CI: 0.25-1.01), (CCTTT)14 (P = 0.02; OR = 2.05, 95%CI: 1.07-3.94), (CCTTT)15 (P = 0.01; OR = 2.25, 95%CI: 1.16-4.35) repeats in UC patients indicated its possible association with higher disease risk which need to be confirmed in a larger sample size.

CONCLUSION

Our results suggest that the NOS2A_ (CCTTT)n gene variations may influence IBD susceptibility in the Moroccan population.

NF-κB signaling in inflammation

The transcription factor NF-κB regulates multiple aspects of innate and adaptive immune functions and serves as a pivotal mediator of inflammatory responses. NF-κB induces the expression of various pro-inflammatory genes, including those encoding cytokines and chemokines, and also participates in inflammasome regulation. In addition, NF-κB plays a critical role in regulating the survival, activation and differentiation of innate immune cells and inflammatory T cells. Consequently, deregulated NF-κB activation contributes to the pathogenic processes of various inflammatory diseases. In this review, we will discuss the activation and function of NF-κB in association with inflammatory diseases and highlight the development of therapeutic strategies based on NF-κB inhibition.

Association of NFKB1 and NFKBIA polymorphisms in relation to susceptibility of Behçet's disease

Behçet's disease (BD) is a chronic inflammatory autoimmune disease. Although raised levels of proinflammatory cytokines in BD have been reported, the pathogenesis is still unknown. The aim of this study was to investigate the association of NFKB1 and NFKBIA polymorphisms and their single and combined analysis effects on susceptibility of BD in Turkish population. We analysed the distribution of NFKB1 -94 ins/del ATTG (rs28362491) and NFKBIA 3' UTR A→G (rs696) polymorphisms using PCR-RFLP method in 89 patients with BD and 190 controls in this population. Statistical analysis of the results was performed by calculating OR, and 95% CI via χ(2) test and using Bonferroni correction. According to the significant results of both single and combined genotype analysis, the frequencies of ins/ins genotype and ins allele of rs28362491 were significantly higher in patients with BD (Pc = 0.003, 0.004, respectively). Also, higher frequencies of the rs696 variant containing AA genotype was found in patients with BD (Pc = 0.0033), whereas no statistical significant differences in distribution of the alleles of rs696 polymorphism in patients and controls. In addition, according to the combined genotype analysis, the wild type of both rs28362491 and rs696 polymorphisms (ins/ins/AA genotype) was also significantly higher in BD cases (Pc = 0.044). Our findings prove that both single and combined genotype analysis of rs28362491 and rs696 polymorphisms indicate that the wild genotypes of both two SNPs (ins/ins and AA genotypes) and ins/ins/AA combined genotype are strongly associated with enhanced risk of BD in a Turkish population.

PTPN2 and NF-κB single nucleotide polymorphisms associated with susceptibility to ulcerative colitis

Ulcerative colitis (UC) is a form of chronic and recurrent bowel disease with unknown etiology. Pieces of evidence suggest that UC should be evolved as a result of inappropriate and ongoing activation of the mucosal immune system driven by the luminal commensal microflora in a genetically susceptible host. Protein tyrosine phosphatase non-receptor type 2 (PTPN2) and nuclear factor-kappa B (NF-κB) play important roles not only in inflammatory pathways, but also in the development of UC. In recent years, association of PTPN2 and NF-κB gene polymorphisms with susceptibility to UC has become a research focus in Western counties, but the studies are controversial in southern China. This paper reviews the PTPN2 and NF-κB gene single nucleotide poly-morphisms (SNPs) associated with susceptibility to UC.

Gene polymorphisms and thyroid function in patients with heart failure

We evaluated nuclear factor kappa B {NFkB, rs28362491 [-94ins/delATTG (W/D)]} and angiotensin converting enzyme {ACE; rs1799752 [Ins(I)/Del(D)]} gene polymorphisms and their correlation with thyroid function in patients with heart failure (HF). Peak oxygen uptake (VO(2)) was evaluated (by Weber classification) during a symptom-limited cardiopulmonary exercise test in 194 patients. Thyroid-stimulating hormone, triiodothyronine (T3), thyroxine (T4), and free (F) T3 and FT4 were also measured. According to their cardiovascular (CV) capacity, patients were subdivided into four groups: group A included patients with peak VO(2) >20 ml/kg/min, group B 16-20 ml/kg/min, group C 10-16 ml/kg/min, and group D 6-10 ml/kg/min. Patients were also genotyped for NFkB and ACE genetic variants. T3 was increased and FT3 was decreased for every raise in Weber's classification (p = 0.007 and p = 0.012, respectively). Del carriers had elevated FT3 levels compared with Ins carriers (p = 0.021). Patients with II genotype had elevated T4 levels compared with ID genotype (p = 0.044). Both T4 and FT4 were decreased in D allele carriers (p = 0.007 and p = 0.045, respectively). Thyroid hormones correlated with CV capacity. Associations between the NFkB and ACE gene polymorphisms and thyroid hormones levels were also observed. Further larger studies are required to clarify genes contribution in HF.

Functional promoter polymorphisms of NFKB1 influence susceptibility to the diffuse type of gastric cancer

In the present study, we report an association between gastric cancer and polymorphisms in NFKB1 (rs28362941 and rs78696119). We employed the PCR-SSCP method to detect gene polymorphisms in 479 gastric cancer cases and 880 controls. The rs28362941 del/del homozygote was significantly associated with gastric cancer development; in particular it was closely associated with diffuse type gastric cancer. The rs78696119 GG homozygote was also associated with the diffuse type of gastric cancer. In young subjects, both polymorphisms were significantly associated with the development of gastric cancer. In addition, both polymorphisms were related to tumor progression such as tumor invasion and lymph node metastasis. The inflammatory cell infiltration into non-cancerous gastric mucosa was greater in the subjects with the rs28362491 del/del or rs78696119 GG genotype when compared to those with the other genotypes. In conclusion, functional polymorphisms of NFKB1 are associated with an increased risk of gastric cancer; in particular they are closely associated with the development of diffuse type of gastric cancer via severe gastric inflammation. These polymorphisms also appear to be associated with gastric cancer progression.

Association between NFKB1 -94 insertion/deletion ATTG polymorphism and risk of intracranial aneurysm

OBJECTIVE

Growing evidence indicates that vascular inflammation is a common phenomenon in the pathogenesis of intracranial aneurysms (IAs). Nuclear factor kappa B is a key molecule that is involved in the vascular inflammation of IA. We hypothesized that an insertion/deletion (ins/del) ATTG polymorphism located between two putative key promoter regulatory elements in the NFKB1 gene may be related to the risk of IA.

METHODS

We performed a case-control study, including 164 patients with IA and 525 healthy controls in a Chinese population using a polymerase chain reaction-polyacrylamide gel electrophoresis assay.

RESULTS

A significantly decreased risk of IA was observed in the ATTG1/ATTG2 and ATTG2/ATTG2 genotypes compared with the ATTG1/ATTG1 genotype (ATTG1/ATTG2 vs. ATTG1/ATTG1: odds ratio [OR]=0.58, 95% confidence interval [95% CI]=0.39-0.87, p=0.007; ATTG2/ATTG2 vs. ATTG1/ATTG1: OR=0.12, 95% CI=0.06-0.23, p<0.001), and also the ATTG2 allele (ATTG2 vs. ATTG1: OR=0.41, 95% CI=0.32-0.54, p<0.001).

CONCLUSION

These findings suggest that the NFKB1 -94ins/del ATTG polymorphism may contribute to the risk of IA.

The frequency of 4 common gene polymorphisms in nonagenarians, centenarians, and average life span individuals

Single nucleotide polymorphisms of angiotensin-converting enzyme (ACE) such as rs1799752, nuclear factor kappa B (NFkB) such as rs28362491 and cholesteryl ester transport protein (CETP) such as rs708272 (TaqB1) and rs5882 (I405V) were evaluated in nonagenarians, centenarians, and average life span individuals (controls). The study population (n = 307; 190 nonagenarians, 12 centenarians and 105 middle-aged controls) was genotyped for ACE, NFkB, and CETP genetic variants. The age of nonagenarian and centenarian group ranged between 90 and 111 years; centenarians and controls age ranged from 99 to 111, and from 18 to 80 years, respectively. The I carriers of ACE I/D gene were fewer in nonagenarians compared to centenarians (37.6% vs 62.5%, P = .016). The I carriers of ACE gene were more frequent in centenarians compared to controls (62% vs 41%, P = .045). No differences in frequency of common NFkB and CETP genotypes between patients with exceptional longevity and middle-aged patients were observed.

Risk association between the NF-κB1 -94ins/delATTG promoter polymorphism and inflammatory bowel diseases: a meta-analysis

BACKGROUND

Extensive investigation of the NF-κB1 -94ins/delATTG promoter polymorphism for risk association with ulcerative colitis (UC) and Crohn's disease (CD) risk has yielded conflicting results.

AIMS

The objective of this meta-analysis was to evaluate the risk association between the NF-κB1 -94ins/delATTG promoter polymorphism and UC and CD.

METHODS

All eligible case-control studies of the association of NF-κB1 -94ins/delATTG promoter polymorphism with UC and CD were identified in the Pubmed and Embase databases. From these data, odds ratios (OR) with 95 % confidence intervals (CI) were calculated. Meta-analysis was performed for alleles (D vs. W) and genotypes (DD + WD vs. WW, DD vs. WW + WD, DD vs. WW, WD vs. WW) in a fixed/random effects model.

RESULTS

Nine case-control studies that included 4,447 cases (2,631 UC and 1,816 CD) and 2,195 controls were identified. Results indicated increased risk association of D allele carriers with UC (D vs. W: OR = 1.08, 95 % CI = 1.01-1.17, P = 0.03; DD vs. WW + WD: OR = 1.16, 95 % CI = 1.01-1.32, P = 0.04 and DD vs. WW: OR = 1.20, 95 % CI = 1.03-1.39, P = 0.02). No risk association was identified with CD.

CONCLUSION

This meta-analysis indicated that the NF-κB1 -94ins/delATTG promoter polymorphism is a risk factor for UC but not CD.

NFKB1 polymorphism is associated with age-related gene methylation in Helicobacter pylori-infected subjects

CpG island aberrant methylation is shown to be an important mechanism in gene silencing. The important role of NF-κB in the inflammatory response to H. pylori colonization has been indicated. We investigated the influence of NFKB1 polymorphisms, -94 ins/del (rs28362491) and -449 C>G (rs72696119), on the aberrant gene methylation under H. pylori infection. Gastric mucosal samples were obtained from sub-subjects without malignancies. Methylation status of genes (p14ARF, p16INK4a, DAPK and CDH1) was determined by methylation-specific PCR (MSP). The genotyping of NFKB1 was performed by PCR-SSCP. There was a strong allelic association between rs28362491 and rs72696119, and all H. pylori-infected -94 del/del homozygotes had a -449 GG genotype. The -94 del/del homozygosity was significantly associated with risk for development of CpG island high methylation (CIHM) (two or more gene methylations), especially DAPK and CDH1 methylations, and the number of methylated genes was significantly higher in -94 del/del homozygotes than in ins/del and ins/ins (ins carrier) H. pylori-infected elder subjects. In addition, this methylated gene number was significantly increased with age in H. pylori-infected del/del homozygotes, but not in infected ins carriers. Furthermore, the inflammation score was significantly higher in H. pylori-infected del/del homozygotes compared to ins carriers. NFKB1 -94 ins/del ATTG polymorphism (rs28362491) was significantly associated with the increased risk for the development of age-related gene methylation in non-cancerous gastric mucosa under H. pylori-induced inflammation.

The NFKB1 (g.-24519delATTG) variant is associated with necrotizing enterocolitis (NEC) in premature infants

OBJECTIVE

While it is known that gene-environment interactions contribute to necrotizing enterocolitis (NEC) pathogenesis, characterization of genetic risk-factors that can predict NEC in preterm infants remains nascent. We hypothesized that altered intestinal immune responses arising from sequence variation in the toll-like receptor (TLR) pathway genes contribute to NEC susceptibility.

MATERIALS AND METHODS

Very low birth weight (VLBW) infants were recruited prospectively in a multi-center, cohort study involving collection of blood samples along with collation of clinical information. DNA obtained from blood samples was used to genotype nine single nucleotide polymorphisms (SNPs) in eight TLR pathway genes by single-base extension. Prevalence of the variant allele was compared between cases and controls using Fisher's exact test.

RESULTS

In our cohort of 271 infants, 15 infants (5.6%) developed NEC, and five died from it. Infants with NEC were less mature (P < 0.001), and were more likely to be African-American (P = 0.007). SNPs in the TLR2, TLR4, TLR5, TLR9, IRAK1, and TIRAP genes were not associated with NEC. The NFKB1 (g.-24519delATTG) variant was present in all infants with NEC but only in 65% of infants without NEC (P = 0.003), while the NFKBIA (g.-1004A>G) variant was present in 13.3% of infants with NEC but in 49% of infants without NEC (P = 0.007). After correcting for multiple comparisons, the NFKB1 and NFKBIA variants remained associated with NEC (P < 0.05).

CONCLUSIONS

These data suggest that TLR genetic variants can alter susceptibility to NEC in VLBW infants and support the hypothesis that genetically programmed differences in the innate immune response contribute to NEC pathogenesis.

Polymorphisms in NF-κB, PXR, LXR, PPARγ and risk of inflammatory bowel disease

AIM: To investigate the contribution of polymorphisms in nuclear receptors to risk of inflammatory bowel disease (IBD).

METHODS: Genotypes of nuclear factor (NF)-κB (NFKB1) NFκB -94ins/del (rs28362491); peroxisome proliferator-activated receptor (PPAR)-γ (PPARγ) PPARγ Pro12Ala (rs 1801282) and C1431T (rs 3856806); pregnane X receptor (PXR) (NR1I2) PXR A-24381C (rs1523127), C8055T (2276707), and A7635G (rs 6785049); and liver X receptor (LXR) (NR1H2) LXR T-rs1405655-C and T-rs2695121-C were assessed in a Danish case-control study of 327 Crohn’s disease patients, 495 ulcerative colitis (UC) patients, and 779 healthy controls. Odds ratio (OR) and 95% CI were estimated by logistic regression models.

RESULTS: The PXR A7635G variant, the PPARγ Pro12Ala and LXR T-rs2695121-C homozygous variant genotypes were associated with risk of UC (OR: 1.31, 95% CI: 1.03-1.66, P = 0.03, OR: 2.30, 95% CI: 1.04-5.08, P = 0.04, and OR: 1.41, 95% CI: 1.00-1.98, P = 0.05, respectively) compared to the corresponding homozygous wild-type genotypes. Among never smokers, PXR A7635G and the LXR T-rs1405655-C and T-rs2695121-C variant genotypes were associated with risk of IBD (OR: 1.41, 95% CI: 1.05-1.91, P = 0.02, OR: 1.63, 95% CI: 1.21-2.20, P = 0.001, and OR: 2.02, 95% CI: 1.36-2.99, P = 0.0005, respectively) compared to the respective homozygous variant genotypes. PXR A7635G (rs6785049) variant genotype was associated with a higher risk of UC diagnosis before the age of 40 years and with a higher risk of extensive disease (OR: 1.34, 95% CI: 1.03-1.75 and OR: 2.49, 95% CI: 1.24-5.03, respectively).

CONCLUSION: Common PXR and LXR polymorphisms may contribute to risk of IBD, especially among never smokers.

Role of the gut microbiota in defining human health

The human superorganism is a conglomerate of mammalian and microbial cells, with the latter estimated to outnumber the former by ten to one and the microbial genetic repertoire (microbiome) to be approximately 100-times greater than that of the human host. Given the ability of the immune response to rapidly counter infectious agents, it is striking that such a large density of microbes can exist in a state of synergy within the human host. This is particularly true of the distal gastrointestinal (GI) tract, which houses up to 1000 distinct bacterial species and an estimated excess of 1 x 10(14) microorganisms. An ever-increasing body of evidence implicates the GI microbiota in defining states of health and disease. Here, we review the literature in adult and pediatric GI microbiome studies, the emerging links between microbial community structure, function, infection and disease, and the approaches to manipulate this crucial ecosystem to improve host health.

The del/del genotype of the nuclear factor-kappaB -94ATTG polymorphism and its relation to aggressive periodontitis

BACKGROUND AND OBJECTIVE

Periodontitis is influenced by specific host-dependent immune responses. Periodontopathogens induce innate immune responses, amongst others, via toll-like receptor 2 (TLR2), resulting in activation of the nuclear transcription factor nuclear factor-kappaB (NF-kappaB). The aim of this case-control study was to evaluate links between genetic variants of these genes and chronic/aggressive periodontitis in a multivariate model.

MATERIAL AND METHODS

A total of 141 patients with periodontitis (63 with chronic periodontitis and 78 with aggressive periodontitis) and 81 controls without periodontitis were included in the study. Polymorphisms in TLR2 (Arg677Trp, Arg753Gln) and in NF-kappaB (-94ins/delATTG) were determined by restriction fragment length polymorphism and fragment length analyses, respectively. Subgingival bacterial colonization was evaluated using a PCR/DNA probe test (micro-Ident).

RESULTS

Although there was no association of the TLR2 polymorphism Arg753Gln with periodontitis, heterozygous carriers (Arg/Gln) were at a higher risk for colonization with bacteria of the 'red complex' (corrected p-value = 0.042). The del/del genotype of the NF-kappaB polymorphism was associated with aggressive periodontitis considering age, gender, smoking and approximal plaque index as potential confounders (odds ratio = 2.81, p = 0.035, 95% confidence interval: 1.08-7.33). del/del carriers had a higher risk for subgingival colonization with Aggregatibacter actinomycetemcomitans (odds ratio = 2.36, p = 0.030, 95% confidence interval: 1.09-5.1; adjusted for age, gender, smoking and pocket depth(bacteria)).

CONCLUSIONS

The del/del genotype of NF-kappaB was shown to be associated with the occurrence of aggressive periodontitis.

NFKB1-94ins/del polymorphism is not associated with lung injury after cardiopulmonary bypass

Nuclear factor (NF)-kappaB (NFKB1)-94ins/del is an important polymorphism that affects promoter activity of the NFKB1 gene and is potentially associated with several inflammatory diseases. We investigated the association of this polymorphism with lung injury after cardiac surgery and cardiopulmonary bypass in a prospective cohort study of 283 patients. Genotyping was performed by high resolution melting analysis; analysis indicated no association of NFKB1 with postoperative lung injury (p = 0.064). Relative risks of the del allele and the del/del genotype were 1.34 (95% CI 1.02-1.75) and 1.74 (95% CI 1.00-3.05) respectively. Logistic regression analysis (with factors including age, peripheral vascular disease and surgical duration as risk factors of lung injury after cardiac surgery with cardiopulmonary bypass) also failed to confirm that the NFKB1 genotype is influential for lung injury (p = 0.113). We conclude that, contrary to some other evidence, the NFKB1-94ins/del polymorphism is not associated with lung injury after cardiac surgery with cardiopulmonary bypass.

Identification of NF-kappaB1 and NF-kappaBIAlpha polymorphisms using PCR-RFLP assay in a Turkish population

A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay was used in a Turkish population to determine the frequency of polymorphisms of the nuclear factor-kappa (NF-kappaB1) and NF-kappaBIA genes, which have been shown to be related to several inflammatory diseases and cancer pathogenesis. Total genomic DNA was isolated from peripheral blood samples taken from 565 healthy volunteers living in Aydin Province. The genomic regions in question were amplified by PCR, and the polymorphisms in these regions were detected by a PCR-RFLP assay. The frequencies were 10.3% for the NF-kappaB1 -94ins/delATTG del/del genotype, 49.1% for del/ins, and 40.6% for ins/ins. The genotype frequencies of the NF-kappaBIA 3'UTR A --> G genotypes were A/A 19.2%, A/G 42.3%, and G/G 38.5%. Distribution of genotype frequencies was tested by Hardy-Weinberg; the NF-kappaB1 gene was in Hardy-Weinberg equilibrium (chi(2) = 3.402, P > 0.05), the NF-kappaBIA gene was not (chi(2) = 8.293, P < 0.05).

Relationship between NFKB1 -94 insertion/deletion ATTG polymorphism and susceptibility of cervical squamous cell carcinoma risk

BACKGROUND

A very high expression of nuclear factor-kappa B protein (nuclear p50, encoded by NFKB1) in high-grade squamous intraepithelial lesion and invasive cancers has been observed. The aim of this study was to determine whether the functional NFKB1 -94 insertion/deletion ATTG polymorphism (rs28362491) is associated with cervical squamous cell carcinoma (CSCC).

MATERIALS AND METHODS

PCR-polyacrylamide gel electrophoresis method was used to genotype the NFKB1 -94 insertion/deletion ATTG polymorphism in 233 women with CSCC and 365 ethnicity-matched healthy control women. The genotyping method was confirmed by the DNA sequencing analysis.

RESULTS

The frequency of ATTG(2)/ATTG(2) genotype and ATTG(2) allele in the CSCC patients was significantly higher than that of controls, indicating that the -94 insertion/deletion ATTG polymorphism in NFKB1 promoter was associated with CSCC [P = 0.001, odds ratio (OR) = 2.560, 95% confidence interval (CI) 1.459-4.492 and P = 0.001, OR = 1.493, 95% CI 1.168-1.908, respectively]. Results of stratified analyses revealed that this polymorphism is associated with younger age (< or =35 years) and positive parametrial invasion but not with tumor differentiation, high clinical stage or lymph node status.

CONCLUSION

Our results indicate that the functional NFKB1 -94 insertion/deletion ATTG polymorphism is associated with CSCC, especially with younger age (< or =35 years) and positive parametrial invasion of CSCC patients.

Transglutaminases in inflammation and fibrosis of the gastrointestinal tract and the liver

Transglutaminases are a family of eight currently known calcium-dependent enzymes that catalyze the cross-linking or deamidation of proteins. They are involved in important biological processes such as wound healing, tissue repair, fibrogenesis, apoptosis, inflammation and cell-cycle control. Therefore, they play important roles in the pathomechanisms of autoimmune, inflammatory and degenerative diseases, many of which affect the gastrointestinal system. Transglutaminase 2 is prominent, since it is central to the pathogenesis of celiac disease, and modulates inflammation and fibrosis in inflammatory bowel and chronic liver diseases. This review highlights our present understanding of transglutaminase function in gastrointestinal and liver diseases and therapeutic strategies that target transglutaminase activities.

Association of NFkB1 -94ins/delATTG promoter polymorphism with ulcerative colitis in Chinese Han population of Hubei Province

AIM: To investigate the association between NFkB1 -94ins/delATTG promoter polymorphism and ulcerative colitis in Chinese Han population of Hubei Province.

METHODS: The NFkB1-94ins/delATTG promoter polymorphism was genotyped in 73 unrelated Chinese patients with ulcerative colitis and 121 healthy controls using polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP). The correlation of allele and genotype frequencies for this locus with the clinical subtypes of ulcerative colitis was analyzed. The results were compared with those obtained in a previous study of Italian population.

RESULTS: No significant differences were found in genotype and allele frequencies of the NFkB1-94ins/delATTG promoter polymorphism between patients with ulcerative colitis and healthy controls. There was no significant correlation between allele and genotype frequencies for this locus and the clinical subtypes of ulcerative colitis (P > 0.05). However, the genotypes (χ² = 13.155, P < 0.05) and allele frequencies (OR = 0.566, 95%CI: 0.413-0.774, P < 0.01) for this locus were significantly different between the Chinese and Italian populations.

CONCLUSION: No association between NFkB1 -94ins/delATTG promoter polymorphism and ulcerative colitis is found in Chinese Han population of Hubei Province.

Functional polymorphism of the NFKB1 gene promoter is related to the risk of dilated cardiomyopathy

Background

Previous studies in experimental and human heart failure showed that nuclear factor kappa B (NF-κB) is chronically activated in cardiac myocytes, suggesting an important involvement of NF-κB in the cardiac remodeling process. A common insertion/deletion (-94 insertion/deletion ATTG, rs28362491) located between two putative key promoter regulatory elements in the NFKB1 gene was identified which seems to be the first potential functional NFKB1 genetic variation. The main goal of the present investigation was to investigate the NFKB1 -94 insertion/deletion ATTG polymorphism in relation to risk of dilated cardiomyopathy (DCM).

Methods

A total of 177 DCM patients and 203 control subjects were successfully investigated. The NFKB1 -94 insertion/deletion ATTG polymorphism was genotyped by using PCR-PAGE.

Results

Genotype frequency of NFKB1 -94 insertion/deletion ATTG polymorphism in DCM patients was significantly different from that in control subjects (P = 0.015) and the ATTG₂ carrier (ATTG₁/ATTG₂ + ATTG₂/ATTG₂) was susceptible to DCM.

Conclusion

Our data suggested that NFKB1 -94 insertion/deletion ATTG polymorphism is associated with DCM.

Clustering of (auto)immune diseases with early-onset and complicated inflammatory bowel disease

Studies in adult inflammatory bowel disease (IBD) patients have highlighted associations with genetic and serologic markers and suggest an association with disease location, behaviour and natural history. Data on patients with Crohn's disease (CD, n=80), ulcerative colitis (UC, n=15) and indeterminate colitis (n=4) were collected. All individuals were analysed for CARD15 R702W, G908R and L1007fs for toll-like receptor 4 (TLR4) Asp299Gly and for anti-Saccharomyces cerevisiae antibodies (ASCA) and atypical perinuclear antineutrophil cytoplasmatic antibodies (pANCA). After a mean of 10.7 years of follow up, the disease behaviour changed in 45% of CD patients, in contrast to disease location, where only 12.5% had a change (p<0.001). The younger the age at diagnosis, the more patients presented with colonic disease (p=0.021). Also, more TLR4 Asp299 Gly variants were found when the age at onset was younger (p=0.018). A large number of concomitant diseases were observed. There was no difference in the prevalence of TLR4 variants nor ASCA or pANCA between the patients with or without concomitant diseases. Patients who progressed more often needed surgery as compared to patients who remained free of stenosing or fistulising disease (27/32 or 84% versus 3/35 or 8.6%, respectively, p<0.0001) and more often had concomitant immune-mediated diseases and a trend for more seroreactivity towards ASCA.

The 3'UTR NFKBIA variant is associated with extensive colitis in Hungarian IBD patients

PURPOSE

In previous studies the NFKBIA 3'UTR (untranslated region) AA genotype was associated with Crohn's disease (CD), while the NFKB1-94ins/delATTG mutation increased the risk for ulcerative colitis (UC). The aim of our study was to investigate these two polymorphisms and patients' response to medical therapy and/or disease phenotype in Hungarian inflammatory bowel disease (IBD) patients.

METHODS

NFKBIA 3'UTR- and NFKB1-94ins/delATTG polymorphisms were investigated in 415 unrelated IBD patients (CD: 266 patients, mean age 35.2 +/- 12.1 years, duration 8.7 +/- 7.5 years; UC patients: 149, mean age 44.4 +/- 15.4 years, duration 10.7 +/- 8.9 years) and 149 controls by PCR-restriction fragment length polymorphism (RFLP) analysis. Detailed clinical phenotypes were determined by reviewing the medical charts.

RESULTS

The NFKBIA 3'UTR and NFKB1-94ins/delATTG genotypes and allele frequencies were not significantly different among IBD and controls. In patients with UC, the 3'UTR GG genotype was associated with extensive colitis (55.3 vs. 29.4%, odds ratio 2.97, 95% confidence interval 1.45-6.08). The presence of variant alleles did not predict response to steroids, infliximab, or need for surgery.

CONCLUSIONS

The NFKBIA 3'UTR GG genotype was associated with an increased risk for extensive colitis in Hungarian patients. In contrast, variant alleles did not predict response to medical therapy or need for surgery.

Genetic polymorphisms of IL-1A, IL-1B, IL-1RN, NFKB1, FAS, and FASL, and risk of silicosis in a Chinese occupational population

OBJECTIVE

To test whether polymorphisms in IL-1, NF-KB, FAS, and FASL genes are associated with risk of silicosis.

METHODS

A case-control study was conducted with 183 silicosis patients and 111 silica-exposed miners who were frequency-matched by age, dust exposure duration, work location, and type of work. Genotype analysis was performed on genomic DNA, using a PCR-RFLP assay.

RESULTS

Individuals carrying the NFKB1 ins/del genotype had a decreased risk of silicosis (adjusted OR = 0.57, 95% CI = 0.32-0.998, P = 0.049) compared with subjects carrying the ins/ins genotype and individuals with the FAS-1377AA homozygote had a decreased risk of silicosis compared with those with the -1377GG genotype (adjusted OR = 0.42, 95% CI = 0.19-0.93, P = 0.03). The analysis of haplotypes of polymorphisms in FAS showed that there was a 2.71-fold (OR = 2.71, 95% CI = 1.22-6.03, P = 0.011) increased risk of silicosis for subjects with alleles of FAS-1377G and FAS-670G, compared with those carrying alleles of FAS-1377G and FAS-670A.

CONCLUSION

Although the polymorphisms at NFKB1, FAS-1377, and extended haplotype FAS-1377G/-670G may play a role in the development of silicosis in the Chinese population, our findings should be verified by larger studies with >1 case/control ratio.

Inflammatory bowel disease: Genetic and epidemiologic considerations

Genome-wide association studies have firmly established that many genomic loci contribute to inflammatory bowel disease, especially in Crohn’s disease. These studies have newly-established the importance of the interleukin 23 and autophagy pathways in disease pathogenesis. Future challenges include: (1) the establishment of precisely causal alleles, (2) definition of altered functional outcomes of associated and causal alleles and (3) integration of genetic findings with environmental factors.

Evaluating the role of the genetic variations of PTPN22, NFKB1, and FcGRIIIA genes in inflammatory bowel disease: a meta-analysis

BACKGROUND

We tested several polymorphisms of genes involved in the mucosal immune system in a population of inflammatory bowel disease (IBD) patients to investigate their possible implication in disease predisposition.

METHODS

Polymorphisms of 3 candidate genes (PTPN22, NFkB1, and FcGRIIIA) were investigated in 649 IBD patients (343 with Crohn's disease [CD] and 306 with ulcerative colitis [UC]), 176 unaffected relatives, and 256 healthy controls. Allele and genotype frequencies were correlated with clinical characteristics and major variants of the CARD15 gene. Our findings were pooled in a meta-analysis with the available studies in the literature.

RESULTS

No significant difference for the PTPN22 and NFkB1 variants was found. In contrast, allele and genotype frequencies of the G559T allele of the FcGRIIIA gene were significantly different in CD patients compared to controls (allele T 12% versus 8%, odds ratio [OR] = 1.58, 95% confidence interval [CI] 1.06-2.35; GT genotype 23% versus 16%, OR = 1.64, 95% CI = 1.08-2.5). However, no significant overtransmission of the T allele was confirmed at the family-based analysis. For all genes, neither an interaction with CARD15 gene, nor a significant difference at genotype/phenotype analysis was demonstrated, included response to medical therapy.

CONCLUSIONS

Although involved in autoimmune diseases, the PTPN22 and NFkB1 genes do not seem involved in the IBD predisposition, also according to meta-analysis results. The association with the G559T polymorphism of the FcGRIIIA gene in CD patients deserves further investigation.

rs1004819 is the main disease-associated IL23R variant in German Crohn's disease patients: combined analysis of IL23R, CARD15, and OCTN1/2 variants

Background

The IL23R gene has been identified as a susceptibility gene for inflammatory bowel disease (IBD) in the North American population. The aim of our study was to test this association in a large German IBD cohort and to elucidate potential interactions with other IBD genes as well as phenotypic consequences of IL23R variants.

Methods

Genomic DNA from 2670 Caucasian individuals including 833 patients with Crohn's disease (CD), 456 patients with ulcerative colitis (UC), and 1381 healthy unrelated controls was analyzed for 10 IL23R SNPs. Genotyping included the NOD2 variants p.Arg702Trp, p.Gly908Arg, and p.Leu1007fsX1008 and polymorphisms in SLC22A4/OCTN1 (1672 C→T) and SLC22A5/OCTN2 (–207 G→C).

Results

All IL23R gene variants analyzed displayed highly significant associations with CD. The strongest association was found for the SNP rs1004819 [P = 1.92×10⁻¹¹; OR 1.56; 95 % CI (1.37–1.78)]. 93.2% of the rs1004819 TT homozygous carriers as compared to 78% of CC wildtype carriers had ileal involvement [P = 0.004; OR 4.24; CI (1.46–12.34)]. The coding SNP rs11209026 (p.Arg381Gln) was protective for CD [P = 8.04×10⁻⁸; OR 0.43; CI (0.31–0.59)]. Similar, but weaker associations were found in UC. There was no evidence for epistasis between the IL23R gene and the CD susceptibility genes CARD15 and SLC22A4/5.

Conclusion

IL23R is an IBD susceptibility gene, but has no epistatic interaction with CARD15 and SLC22A4/5. rs1004819 is the major IL23R variant associated with CD in the German population, while the p.Arg381Gln IL23R variant is a protective marker for CD and UC.

Association of NFKB1 -94ins/del ATTG promoter polymorphism with susceptibility to and phenotype of Graves' disease

Recently, a functional polymorphism in the NFKB1 gene promoter (-94ins/del ATTG) has been identified and associated with chronic inflammatory diseases. The aim of this study was to analyze the association of NFKB1 polymorphism with susceptibility to and phenotype of Graves' disease (GD). The initial case-control association study, performed in a Polish-Warsaw cohort (388 GD patients and 688 controls), was followed by the two replication studies performed in Polish-Gliwice and Japanese-Kurume cohorts (198 GD patients and 194 controls, and 424 GD patients and 222 controls, respectively). The frequency of the -94del ATTG (D) allele was increased in GD compared to controls in Warsaw cohort. This finding was replicated in Gliwice cohort. Combining both Polish-Caucasian cohorts showed that the NFKB1 polymorphism was significantly associated with susceptibility to GD with a codominant mode of inheritance (P=0.00005; OR=1.37 (1.18-1.60)). No association with GD was found in Japanese cohort. However, subgroup analysis in Japanese GD patients revealed a correlation between the NFKB1genotype and the development of ophthalmopathy (P=0.009; OR=1.49 (1.10-2.01)), and the age of disease onset (P=0.009; OR=1.45 (1.09-1.91)). Our results suggest that NFKB1 -94ins/del ATTG polymorphism may be associated with susceptibility to and/or phenotype of GD.

The role of the Toll receptor pathway in susceptibility to inflammatory bowel diseases

The intestinal flora has long been thought to play a role either in initiating or in exacerbating the inflammatory bowel diseases (IBD). Host defenses, such as those mediated by the Toll-like receptors (TLR), are critical to the host/pathogen interaction and have been implicated in IBD pathophysiology. To explore the association of genetic variation in TLR pathways with susceptibility to IBD, we performed a replication study and pooled analyses of the putative IBD risk alleles in NFKB1 and TLR4, and we performed a haplotype-based screen for association to IBD in the TLR genes and a selection of their adaptor and signaling molecules. Our genotyping of 1539 cases of IBD and pooled analysis of 4805 cases of IBD validates the published association of a TLR4 allele with risk of IBD (odds ratio (OR): 1.30, 95% confidence interval (CI): 1.15-1.48; P=0.00017) and Crohn's disease (OR: 1.33, 95% CI: 1.16-1.54; P=0.000035) but not ulcerative colitis. We also describe novel suggestive evidence that TIRAP (OR: 1.16, 95% CI: 1.04-1.30; P=0.007) has a modest effect on risk of IBD. Our analysis, therefore, offers additional evidence that the TLR4 pathway - in this case, TLR4 and its signaling molecule TIRAP - plays a role in susceptibility to IBD.

Molecular pathogenesis of inflammatory bowel disease: genotypes, phenotypes and personalized medicine

Crohn's disease (CD) and ulcerative colitis (UC), also known as inflammatory bowel diseases (IBD), are characterized by chronic inflammation of the gastrointestinal tract. IBD is among the few complex diseases for which several genomic regions and specific genes have been identified and confirmed in multiple replication studies. We will review the different loci implicated in disease risk in the context of three proposed mechanisms leading to chronic inflammation of the gut mucosa: 1) deregulation of the innate immune response to enteric microflora or pathogens; 2) increased permeability across the epithelial barrier; and 3) defective regulation of the adaptive immune system. As our knowledge of genetic variation, analytical approaches and technology improves, additional genetic risk factors are expected to be identified. With the identification of novel risk variants, additional pathophysiological mechanisms are likely to emerge. The resulting discoveries will further our molecular understanding of IBD, potentially leading to improved disease classification and rational drug design. Moreover, these approaches and tools can be applied in the context of variable drug response with the goal of providing more personalized clinical management of patients with IBD.