SMAD3 rs17228212 Gene Polymorphism Is Associated with Reduced Risk to Cerebrovascular Accidents and Subclinical Atherosclerosis in Anti-CCP Negative Spanish Rheumatoid Arthritis Patients

Rheumatoid arthritis (RA) is a complex polygenic inflammatory disease associated with accelerated atherosclerosis and increased risk of cardiovascular (CV) disease. Previous genome-wide association studies have described SMAD3 rs17228212 polymorphism as an important signal associated with CV events. The aim of the present study was to evaluate for the first time the relationship between this gene polymorphism and the susceptibility to CV manifestations and its potential association with the presence of subclinical atherosclerosis assessed by the evaluation of carotid intima-media thickness (cIMT) in patients with RA.

Methods

One thousand eight hundred and ninety-seven patients fulfilling classification criteria for RA were genotyped for SMAD3 rs17228212 gene polymorphism through TaqMan genotyping assay. Also, subclinical atherosclerosis determined by the assessment of cIMT was analyzed in a subgroup of these patients by carotid ultrasonography.

Results

No statistically significant differences were observed when allele frequencies of RA patients with or without CV events were compared. Nevertheless, when RA patients were stratified according to anti-cyclic citrullinated peptide (anti-CCP) status, we found that in RA patients who were negative for anti-CCP antibodies, the presence of C allele of SMAD3 rs17228212 polymorphism conferred a protective effect against the risk of cerebrovascular accident (CVA) after adjustment for demographic and classic CV risk factors (HR [95%CI]=0.36 [0.14–0.94], p=0.038) in a Cox regression model. Additionally, correlation between the presence of C allele of SMAD3 rs17228212 polymorphism and lower values of cIMT was found after adjustment for demographic and classic CV risk factors (p-value=0.0094) in the anti-CCP negative RA patients.

Conclusions

Our results revealed that SMAD3 rs17228212 gene variant is associated with lower risk of CVA and less severe subclinical atherosclerosis in RA patients negative for anti-CCP antibodies. These findings may have importance to establish predictive models of CV disease in RA patients according to anti-CCP status.     

Subclinical Atherosclerosis in Patients with Rheumatoid Arthritis and Low Cardiovascular Risk: The Role of von Willebrand Factor Activity

Background

To evaluate association between von Willebrand factor (vWF) activity, inflammation markers, disease activity, and subclinical atherosclerosis in patients with rheumatoid arthritis (RA) and low cardiovascular risk.

Methods

Above mentioned parameters were determined in blood samples of 74 non-diabetic, normotensive, female subjects, with no dyslipidemia(42 patients, 32 matched healthy controls, age 45.3±10.0 vs. 45.2±9.8 years). Intima-media thickness (IMT) was measured bilaterally, at common carotid, bifurcation, and internal carotid arteries. Subclinical atherosclerosis was defined as IMT>IMT_mean+2SD in controlsat each carotid level and atherosclerotic plaque as IMT>1.5 mm. Majority of RA patients were on methotrexate (83.3%), none on steroids >10 mg/day or biologic drugs. All findings were analysed in the entire study population and in RA group separately.

Results

RA patients with subclinical atherosclerosis had higher vWF activity than those without (133.5±69.3% vs. 95.3±36.8%, p<0.05). Predictive value of vWF activity for subclinical atherosclerosis was confirmed by logistic regression. vWF activity correlated significantly with erythrocyte sedimentation rate, fibrinogen, modified disease activity scores (mDAS28–ESR, mDAS28–CRP), modified Health Assessment Questionnaire (p<0.01 for all), duration of smoking, number of cigarettes/day, rheumatoid factor concentration (p<0.05 for all), and anti-CCP antibodies (p<0.01). In the entire study population, vWF activity was higher in participants with subclinical atherosclerosis (130±68% vs. 97±38%, p<0.05) or atherosclerotic plaques (123±57% vs. 99±45%, p<0.05) than in those without. Duration of smoking was significantly associated with vWF activity (β 0.026, p = 0.039).

Conclusions

We demonstrated association of vWF activity and subclinical atherosclerosis in low-risk RA patients as well as its correlation with inflammation markers, all parameters of disease activity, and seropositivity. Therefore, vWF might be a valuable marker of early atherosclerosis in RA patients.     

Association of SLC22A4 Gene Polymorphism with Rheumatoid Arthritis in the Chinese Population

Rheumatoid arthritis (RA) is a chronic inflammatory disease with complex genetic factors. Single‐nucleotide polymorphisms (SNPs) in the SLC22A4 gene have been previously reported to be associated with RA in Japanese but not European populations. This study further investigated the association of SLC22A4 polymorphisms, in particular slc2F1/slc2F2, with RA in the Chinese population, the largest Asian population. A total of 160 human subjects with 95 RA patients and 65 healthy controls were genotyped for slc2F1‐G/A and slc2F2‐C/T polymorphisms. The results showed that there was a significant difference in the genotype distribution of these two polymorphisms between the two groups. In addition, the presence of slc2F1 A allele and slc2F2 T allele carries a 1.93‐fold and 2.14‐fold increased risk for anticyclic citrullinated peptide (CCP) positivity, respectively. Overall, this study provided evidence that SLC22A4 gene polymorphisms played important roles in the etiology of RA in the largest Asian population, the Chinese population.     

Analysis of Neuropeptide S Receptor Gene (NPSR1) Polymorphism in Rheumatoid Arthritis

Background

Polymorphism in the neuropeptide S receptor gene NPSR1 is associated with asthma and inflammatory bowel disease. NPSR1 is expressed in the brain, where it modulates anxiety and responses to stress, but also in other tissues and cell types including lymphocytes, the lungs, and the intestine, where it appears to be up-regulated in inflammation. We sought to determine whether genetic variability at the NPSR1 locus influences the susceptibility and clinical manifestation of rheumatoid arthritis (RA).

Methodology/Principal Findings

From the Epidemiological Investigation of Rheumatoid Arthritis (EIRA) case-control study, 1,888 rheumatoid arthritis patients and 888 controls were genotyped for 19 single-nucleotide polymorphisms (SNPs) spanning the entire NPSR1 gene and 220 KB of DNA on chromosome 7p14. The association between individual genetic markers and their haplotypic combinations, respectively, and diagnosis of RA, presence of autoantibodies to citrullinated proteins (ACPA), and disease activity score based on 28 joints (DAS28) was tested. There was no association between diagnosis of RA and NPSR1 variants. However, several associations of nominal significance were detected concerning susceptibility to ACPA-negative RA and disease activity measures (DAS28). Among these, the association of SNP rs324987 with ACPA-negative RA [(p = 0.004, OR = 0.674 (95% CI 0.512–0.888)] and that of SNP rs10263447 with DAS28 [p = 0.0002, OR = 0.380 (95% CI 0.227–0.635)] remained significant after correction for multiple comparisons.

Conclusions/Significance

NPSR1 polymorphism may be relevant to RA susceptibility and its clinical manifestation. Specific alleles at the NPSR1 locus may represent common risk factors for chronic inflammatory diseases, including RA.     

Effect of MPG Gene rs2858056 Polymorphism,Copy Number Variation,and Level of Serum MPG Protein on the Risk for Rheumatoid Arthritis

Objective

This study examined the role of SNP rs2858056 of the MPG gene on the incidence and severity of rheumatoid arthritis (RA).

Methods

This cohort study enrolled 365 RA patients and 375 age- and gender-matched healthy controls, all of whom had Han Chinese ethnicity and were from Taiwan. Gene polymorphism of the SNP rs2858056 of MPG was determined from genomic DNA. Allelic frequencies and genotypes were compared among cases and controls. Quantitation of rs2858056 copy number variation (CNV) was determined. Serum samples from RA patients and controls were analyzed to determine serum levels of MPG. The relationship between rs2858056 polymorphism and clinical manifestations of RA was evaluated.

Results

Our results indicated a statistically significant difference in genotype frequency distributions at rs2858056 for RA patients and controls (p = 0.05) and a significant difference in allelic frequency in patients and controls (p = 0.04). Furthermore, there was a significantly greater level of serum MPG protein in patients than controls (p < 0.001). However, the cases and controls had no significant differences in MPG CNV (p = 0.12). We also did not detect any association of the MPG rs2858056 with rheumatoid factor (RF), extraarticular involvement, or bone erosion in the RA patients.

Conclusion

Our study suggests that RA is associated with a polymorphism in the MPG gene (rs2858056) and increased serum level of the MPG protein.     

Gene Polymorphisms and Pharmacogenetics in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a systemic, chronic and inflammatory disease of unknown etiology with genetic predisposition. The advent of new biological agents, as well as the more traditional disease-modifying antirheumatic drugs, has resulted in highly efficient therapies for reducing the symptoms and signs of RA; however, not all patients show the same level of response in disease progression to these therapies. These variations suggest that RA patients may have different genetic regulatory mechanisms. The extensive polymorphisms revealed in non-coding gene-regulatory regions in the immune system, as well as genetic variations in drug-metabolizing enzymes, suggest that this type of variation is of functional and evolutionary importance and may provide clues for developing new therapeutic strategies. Pharmacogenetics is a rapidly advancing area of research that holds the promise that therapies will soon be tailored to an individual patient’s genetic profile.     

The Role of the rs1544410 Polymorphism of Vitamin D Receptor Gene in Breast Cancer Susceptibility

This study was devised to investigate the genetic effect modification of the BsmI polymorphism associated with the susceptibility to breast cancer. Case–control studies of the BsmI polymorphism and breast cancer were searched. A total of 17 eligible publications were included in our final analysis. Pooled ORs and 95 % CIs were obtained by means of fixed effects model. The general and stratified analyses according to ethnicity showed that the association between the BsmI polymorphism and the risk of breast cancer was not statistically significant. However, the subgroup of the hospital-based studies was found to confer protection against the disease (OR_BBvs.bb = 0.83, 95 % CI = 0.71–0.97, P _h = 0.571; OR_BBvs.Bb+bb = 0.86, 95 % CI = 0.74–1.00, P _h = 0.903; OR_{allele B vs. allele b} = 0.92, 95 % CI = 0.86–0.99, P _h = 0.337). Our results suggested that the presence of the BsmI polymorphism may contribute to the susceptibility of breast cancer. It is necessary that future large-scale studies should be conducted to further confirm the association between the BsmI polymorphism and breast cancer risk.     

Role of Key TYMS Polymorphisms on Methotrexate Therapeutic Outcome in Portuguese Rheumatoid Arthritis Patients

Background

Therapeutic outcome of rheumatoid arthritis (RA) patients treated with methotrexate (MTX) can be modulated by thymidylate synthase (TS) levels, which may be altered by genetic polymorphisms in TS gene (TYMS). This study aims to elucidate the influence of TYMS polymorphisms in MTX therapeutic outcome (regarding both clinical response and toxicity) in Portuguese RA patients.

Methods

Clinicopathological data from 233 Caucasian RA patients treated with MTX were collected, outcomes were defined and patients were genotyped for the following TYMS polymorphisms: 1) 28 base pairs (bp) variable number tandem repeat (rs34743033); 2) single nucleotide polymorphism C>G (rs2853542); and 3) 6 bp sequence deletion (1494del6, rs34489327). Chi-square and binary logistic regression analyses were performed, using genotype and haplotype-based approaches.

Results

Considering TYMS genotypes, 3R3R (p = 0.005, OR = 2.34), 3RC3RG (p = 0.016, OR = 3.52) and 6bp− carriers (p = 0.011, OR = 1.96) were associated with non-response to MTX. Multivariate analysis confirmed the increased risk for non-response to MTX in 6bp− carriers (p = 0.016, OR = 2.74). Data demonstrated that TYMS polymorphisms were in linkage disequilibrium (p<0.00001). Haplotype multivariate analysis revealed that haplotypes harboring both 3R and 6bp− alleles were associated with non-response to MTX. Regarding MTX-related toxicity, no statistically significant differences were observed in relation to TYMS genotypes and haplotypes.

Conclusion

Our study reveals that TYMS polymorphisms could be important to help predicting clinical response to MTX in RA patients. Despite the potential of these findings, translation into clinical practice needs larger studies to confirm these evidences.     

Gender Differences in Latin-American Patients With Rheumatoid Arthritis

BackgroundData on the effect of gender in rheumatoid arthritis (RA) in non-Caucasian populations is scarce. Latin America and the Caribbean (LAC) is a large population with unique characteristics, including high admixture.ObjectiveOur aim was to examine the effect of gender in patients with RA in LAC.MethodsThis was a 2-phase study. First we conducted a cross-sectional and analytical study in which 1128 consecutive Colombian patients with RA were assessed. Second, a systematic review of the literature was done to evaluate the effect of gender in LAC patients with RA.ResultsOur results show a high prevalence of RA in LAC women with a ratio of 5.2 women per man. Colombian women with RA are more at risk of having an early age at onset and developing polyautoimmunity and abdominal obesity, and they perform more household duties than their male counterparts. However, male gender was associated with the presence of extra-articular manifestations. Of a total of 641 potentially relevant articles, 38 were considered for final analysis, in which several factors and outcomes related to gender were identified.ConclusionsRA in LAC women is not only more common but presents with some clinical characteristics that differ from RA presentation in men. Some of those characteristics could explain the high rates of disability and worse prognosis observed in women with RA in LAC.     

类风湿性关节炎患者EBV感染情况分析

目的:检测类风湿性关节炎患者血清EBV(Epstein-Barr virus)衣壳抗原IgA抗体(VCA-IgA),分析EBV感染与类风湿性关节炎的相关性.方法:用酶联免疫吸附试验(ELISA)检测92例确诊为类风湿性关节炎患者和80例体检健康者血清VCA-IgA抗体,分析两组人群EBV VCA-IgA阳性率.结果:类风湿性关节炎患者VCA-IgA抗体阳性率为9.8％(9/92);健康对照组阳性率为2.4％ (2/85)(x2=4.038,P＜0.05).结论:类风湿性关节炎患者血清EBV VCA-IgA抗体检出率明显高于健康对照组,提示部分类风湿性关节炎患者发病与EBV感染有关.     

Association of the Common Catalase Gene Polymorphism rs1001179 With Glycated Hemoglobin and Plasma Lipids in Hyperlipidemic Patients

Catalase represents perhaps the most effective antioxidant defense in the body under conditions of increased oxidative stress, and rs1001179 (CAT-262C >T) is its most extensively studied gene polymorphism. Using an established PCR–RFLP method for genotyping, we examined the association of rs1001179 with glycated hemoglobin (HbA1c) and plasma lipids using univariate analyses with age, sex, body mass index (BMI), smoking, and alcohol abuse as covariates, in a group of dyslipidemic patients from northern Greece. Our results suggest that the TT genotype is a risk factor for increased HbA1c and plasma triglycerides, and that this association is modulated by the BMI and/or age of the patients.     

Low Incidence of Rheumatoid Factor and Autoantibodies in Nigerian Patients with Rheumatoid Arthritis

Sera from 53 Nigerian patients satisfying the American Rheumatism Association criteria for a diagnosis of definite or probable rheumatoid arthritis and sera from sick and healthy Nigerian controls were tested for rheumatoid factor, autoantibodies, and immunoglobulin levels. Rheumatoid factor and autoantibodies were found no more frequently in patients with rheumatoid arthritis than in controls. These findings confirm the clinical impression that Nigerian patients with polyarthritis satisfying the criteria for a diagnosis of rheumatoid arthritis differ from Caucasian patients with the disease in a number of important respects. They suggest that either these patients do not have rheumatoid arthritis but a distinct clinical syndrome or that in Nigeria the course of rheumatoid arthritis is modified by genetic or environmental factors.     

Association study of CCR6 rs3093024 with Rheumatoid Arthritis in a Pakistani cohort

C-C Chemokine receptor 6 (CCR6), an important protein in inflammatory and immunological responses, has been previously reported to be associated with rheumatoid arthritis (RA). Therefore, in order to replicate these findings, a case-control study was conducted on 500 subjects (including 250 RA patients and 250 healthy controls) of Pakistani origin. The aim of this study was to determine the association of CCR6 rs3093024 variant with RA and identify its role in splicing events using bioinformatics tools. The clinical and demographic characteristics of the patients were collected using a well-designed questionnaire. The genotype frequencies of CCR6 rs3093024 variant were determined using tetra-primer ARMS-PCR (amplification of refractory mutation system-polymerase chain reaction) method. A significant difference was found between CCR6 rs3093024 genotype frequencies [P = 0.0016, χ² = 12.915]. Similarly, a significant difference in the allele frequencies between RA patients and healthy controls was also observed [P = 0.0003 and OR (95% CI) = 0.63 (0.49–0.80)]. The stratification of patients showed that there was a significant increase in AA genotype against AG + GG in patients [P = 0.0014, OR (95% CI) = 2.0 (1.32–3.02)]. Furthermore, using bioinformatics analysis, it was found that CCR6 rs3093024 variant might create a potential splicing enhancer motif (SF2/ASF (IgM-BRCA1) with score of 77.92; Threshold 70.53), which might have important impact on the product of this gene. This study suggests that the A variant of CCR6 rs3093024 variant is significantly associated with RA-risk and its G variant is protective in Pakistani population but a multi-cohort large sized population study is needed to elucidate these results. Moreover, functional studies are needed to highlight the effects of this polymorphism on the function of CCR6 gene.     

Differential Gene Expression in Synovium of Rheumatoid Arthritis and Osteoarthritis

Rheumatoid arthritis (RA) and osteoarthritis (OA) are the major types of arthritis. Although both diseases are characterized by joint destruction, their etiologies are different. To get insights into pathophysiological pathways, we used the suppression subtractive hybridization (SSH) method to identify differentially expressed genes in RA. DNA sequencing identified 12 gene products including cytoskeletal γ-actin and extracellular matrix components such as fibronectin, collagen IIIα₁, and superficial zone protein. Interferon γ-inducible genes such as a novel thiol reductase, two genes of unknown function (HSIFNIN4, RING3), and annexin II were also found. Two genes encoded proteins involved in proliferation such as elongation factor 1α and the granulin precursor. Furthermore, the protease cathepsin B and synovial phospholipase A2 group IIA were detected by SSH. To confirm the differential expression of the genes, we performed RT-PCR analyses of RA and OA synovial tissues. Compared to OA patients, 9 of the 12 genes were overexpressed in RA, suggesting that SSH is a powerful tool for the detection of differential gene expression in synovial tissues. Further characterization of the gene products may help to identify pathophysiological mechanisms in arthritic diseases.     

An Osteoprotegerin Gene Polymorphism Is Associated with an Increased Risk of Hip Fracture in Japanese Patients with Rheumatoid Arthritis: Results from the IORRA Observational Cohort Study

Introduction

Patients with rheumatoid arthritis (RA) have a higher prevalence of osteoporosis and hip fracture than healthy individuals. Multiple genetic loci for osteoporotic fracture were identified in recent genome-wide association studies. The purpose of this study was to identify genetic variants associated with the occurrence of hip fracture in Japanese patients with RA.

Methods

DNA samples from 2,282 Japanese patients with RA were obtained from the DNA collection of the Institute of Rheumatology Rheumatoid Arthritis cohort (IORRA) study. Six single nucleotide polymorphisms (SNPs) that have been reported to be associated with fractures in recent studies were selected and genotyped. Forty hip fractures were identified with a maximum follow-up of 10 years. The genetic risk for hip fracture was examined using a multivariate Cox proportional hazards regression model.

Results

The risk analyses revealed that patients who are homozygous for the major allele of SNP rs6993813, in the OPG locus, have a higher risk for hip fracture (hazard ratio [95% CI]  = 2.53 [1.29–4.95], P  = 0.0067). No association was found for the other SNPs.

Conclusions

Our results indicate that an OPG allele is associated with increased risk for hip fracture in Japanese patients with RA.     

英夫利昔单抗治疗类风湿关节炎疗效预测因素研究

目的:分析应用英夫利昔单抗(INF)治疗的类风湿关节炎(RA)患者的临床和实验等指标,筛选出可预测INF疗效的因素.方法:以应用INF治疗的40例RA患者为研究对象,收集基线和第14用的临床和实验等指标.应用聚合酶链反应一限制性片断长度分析法(PCR-RFLP)检测RA患者的肿瘤坏死因子α-308(TNFα-308)A/G的基因多态性.达到ACR50%-70%改善的的被判断为INF治疗反应好.采用Logistic回归模型筛选出可预测疗效的因素.结果:治疗14周后.携带TNF-308G/G基因型的RA患者,达到ACR20、ACR50、ACR70改善标准的患者人数的百分率分别为93%、64%和30%;A/G基因型,ACR20、ACR50、ACR70的百分率分别为60%、40%和20%.多因素Logistic回归分析显示,基线值中高DAS28评分和携带TNF-308G/G基因型的RA患者,对INF治疗反应好,其OR值分别为1.97(95%CI为1.74-3.13,P＜0.01)和2.02(95%CI为1.93-3.91,P＜0.01).结论:高DAS28评分及携带TNF-308 G/G基因型的RA患者对INF治疗有更好的应答.RA患者的DAS28评分及携带TNF-308 G基因型可能可作为INF治疗RA疗效的预测指标.     

XPD Gene rs13181 Polymorphism and DNA Damage in Human Lymphocytes

Genetic heterogeneity influencing enzyme activity may change the capacity to repair DNA damage induced by environmental and endogenous factors. This study aims to assess the impact of Lys751Gln (A/C) polymorphism in the XPD gene, encoding an enzyme involved in the nucleotide excision repair pathway, on individual DNA damage. The DNA damage in human lymphocytes (% DNA in the tail) was quantified by means of single-cell gel electrophoresis. Baseline levels of DNA damage significantly differ between AA homozygotes and carriers of the C allele, and the observed differences were not related to age, gender, or smoking status. It seems that the AA variant is associated with enhanced protection against oxidative DNA damage.