Rheumatoid arthritis and genetic variations in cytokine genes: a population-based study in Kashmir Valley

Comparison of glucocorticoids and painkiller prescribed days between rheumatoid arthritis patients receiving early and late treatment with a biological agent via a population-based cohort study

Comparison between early biologics treatment and late biologics treatment of rheumatoid arthritis (RA) patients in decreasing prescription days of glucocorticoids and painkillers by using the Taiwan National Health Insurance Research database from January 1, 1997 to December 31, 2013. We defined early use of biologics as biologics prescribed within 2.24 years after the RA diagnosis, and the late use of biologics was defined as those prescribed after 2.24 years of the RA diagnosis. These definitions are based on previous studies defining early arthritis as arthritis within 2 years of diagnosis, while we needed another 3 months for application biologics here in Taiwan, which equals a total of 2.24 years. Among the 821 patients, 410 patients (50%) were classified in the Early group, and the other 411 patients (50%) were classified in the Late group. The use of any of these 3 types of medication, including steroids, disease modifying antirhuematic drugs, and nonsteroid anti-inflammatory drug (NSAID) was changed significantly after biologics treatment. Comparing between before and after biologics treatment, oral medication was significantly tapered (all P < .0001). The results show that men are 1.81 times more likely than women to taper oral glucocorticoids and NSAIDs. Younger age (<45) patients are 1.91 times more likely to taper steroids and NSAIDs than those aged over 65 years old. Both gender and age were found to be independent factors that could decrease days of prescription of both steroids and NSAIDs in early use of biologics agents. This study indicates that younger patients only need short-term (2.53 ± 1.92 years, P = .03) and early treatment with biologics (within 2.24 years of diagnosis of RA), just in order to taper steroids and NSAIDs to less than 50% compared to the steroids and NSAIDs doses before biologics treatment.

Genetic polymorphisms of ACE I/D, IL-1β G > A and IL-4 VNTR among Egyptian subjects with rheumatoid arthritis

BACKGROUND

Various reports examined the contribution of ACE I/D, IL-1β G > A and IL-4 VNTR with the susceptibility to RA but with conflicting findings. The goal of this study is to assess the impact of these three variants with the susceptibility, clinical and biochemical markers in addition to different composite indices of RA.

SUBJECTS AND METHODS

This case-control survey enclosed 120 RA Egyptian patients who were emulated with 150 healthy controls from the same territory. Their genomic DNA was genotyped utilising the PCR approach.

RESULTS

RA patients with ACE allele (D) and IL-4 VNTR allele (2 R) were expressively higher emulated with healthy controls (p < .05). Nevertheless, RA patients with IL-1β (A allele) failed to achieve an apparent significant emulated with healthy controls (p > .05).

CONCLUSIONS

This work specifies a noteworthy association for ACE I/D and IL-4 VNTR but not IL-1β G > A polymorphisms with RA susceptibility among Egyptian subjects.

Proinflammatory Cytokines (IL-1, -6, -8, -15, -17, -18, -23, TNF-α) Single Nucleotide Polymorphisms in Rheumatoid Arthritis-A Literature Review

Conducted studies highlight that a mixture of genetic and environmental factors is responsible for rheumatoid arthritis (RA) development. This study aimed to analyze the available literature for the relationship between, on the one hand, single-nucleotide polymorphisms (SNPs) in the proinflammatory cytokines genes interleukin-1 (IL-1), -6, -8, -15, -17, -18, and -23, and tumor necrosis factor-alpha (TNF-α), and on the other hand, RA susceptibility, severity, and patients' response to applied treatment. The PubMed database was searched for sources. Preference was given to articles which were published within the past 20 years. Data indicate that the relationship between selected SNPs in proinflammatory cytokines genes and susceptibility to developing RA is inconclusive, and it depends on the ethnicity of the population. Although the allelic and genotypic frequencies of many SNPs in proinflammatory cytokines genes analyzed did not differ between RA patients and healthy controls, deeper analysis showed that these polymorphisms have a relationship with clinicopathological features of RA. SNPs in proinflammatory cytokines genes also "modify patients' response" to applied treatment. Further studies, on larger cohorts of subjects and in different populations, should be conducted to elucidate the role of SNPs in IL-1, -6, -8, -15, -17, -18, and -23, and TNF-α genes in RA patients.

The association between interleukin-6 promoter polymorphisms and rheumatoid arthritis by ethnicity: A meta-analysis of 33 studies

OBJECTIVE

We performed a meta-analysis to determine the effect Interleukin-6 (IL-6) promoter polymorphism (-174 G>C, -572 G>C, and -597 G>A) have on the development rheumatoid arthritis (RA) by ethnicity.

MATERIAL AND METHODS

PubMed, EBSCO, LILACS, and Scopus databases were searched for studies exploring the association between any IL6 polymorphisms and RA until November 2018. Genotype distributions were extracted and, depending on the level heterogeneity, determined by the ψ²-based Q test and the Inconsistency Index (I²), fixed-effects or random-effects models were used to calculate pooled odds ratios (ORs) with 95% confidence intervals (95%CIs) for the heterozygous, homozygous, dominant, recessive, and allelic genetic models.

RESULTS

From 708 identified publications, 33 were used in this analysis. For the -174 polymorphism, Asians (OR_heterozygous=7.57, 95%CI: 2.28-25.14, OR_homozygous=5.84, 95%CI: 2.06-16.56, OR_dominant=7.21, 95%CI: 2.30-22.63, OR_recessive=5.04, 95%CI: 1.78-14.28, OR_allelic=6.60, 95%CI: 2.26-19.28, p<.05) and Middle East countries (OR_heterozygous=2.30, 95%CI: 1.10-4.81, OR_dominant=2.27, 95%CI: 1.22-4.22, OR_allelic=2.29, 95%CI: 1.24-4.23, p<.05) were associated with a significant risk of developing RA. Whereas, for Latinos, the C-allele was associated with a benefit (OR_homozygous=0.26, 95%CI: .08-.82, OR_recessive=.25, 95%CI: .08-.80, p<.05). For the -572 polymorphism, Asians demonstrated a significant association for the homozygous and recessive genetic models (8 studies, OR_homozygous=1.56, 95%CI: 1.16-2.09, OR_recessive=1.63, 95%CI: 1.08-2.45, p<.05). For the -597 polymorphism, no association was observed.

CONCLUSIONS

Here, the -174 G>C polymorphism increased the risk of developing RA in Asians and Middle East populations. Interestingly, for Latinos, the polymorphism was associated with a benefit. For the -572 polymorphism, only the Asian population showed an increased risk of developing RA for the CC genotype.

Association of interleukin-6 promoter polymorphism with rheumatoid arthritis: a meta-analysis with trial sequential analysis

OBJECTIVES

The association of interleukin-6 (IL-6) -174G/C (rs1800795) and IL-6 -572G/C (rs1800796) single-nucleotide polymorphism (SNP) with the risk of acquiring rheumatoid arthritis (RA) was inconsistent among previous studies. This paper aims to investigate the association between IL-6 promoter polymorphism with RA in different ethnics.

METHODS

Relevant studies were searched using Medline and Google Search engines; STATA software was used to perform the meta-analysis. Pooled odds ratios (OR) were calculated to estimate the potential genetic associations. Subgroup analysis and sensitivity analysis were applied to explore the sources of heterogeneity. Lastly, we used TSA (trial sequential analysis) software to verify the reliability of meta-analysis results.

RESULTS

A total of 18 studies were included, involving 8116 subjects (3820 RA patients and 4296 controls). We found a tendency to associate RA with the IL-6 -174G/C allele in Asians (C vs G: OR = 4.56, 95% CI = 1.85-11.23; P < 0.001); with IL-6 -572G/C genotype or allele frequencies, there was no statistical differences between RA patients and controls (P > 0.05). TSA results indicate that the current meta-analysis can draw conclusions.

CONCLUSIONS

IL-6-174G/C gene polymorphism were associated with increased risk of RA in Asians, but not in Caucasians. There was no association between IL-6 -572G/C gene polymorphism and the risk of RA. Key Points • Although the association between interleukin-6 (IL-6) promoter polymorphism and rheumatic arthritis (RA) has been discussed in the previous meta-analysis, their conclusions are inconsistent. • In this study, trial sequential analysis (TSA) was introduced into the meta-analysis, and the following two important conclusions were confirmed: (1) IL-6-174G/C gene polymorphism was associated with increased risk of RA in Asians, but not in Caucasians. (2) There was no association between IL-6 -572G/C gene polymorphism and the risk of RA.

Associations between Polymorphisms in the IL-1 Gene and the Risk of Rheumatoid Arthritis and Systemic Lupus Erythematosus: Evidence from a Meta-Analysis

BACKGROUND

Previous studies on polymorphisms in interleukin-1 (IL-1) and the risk of rheumatoid arthritis (RA)/systemic lupus erythematosus (SLE) yielded inconsistent results.

OBJECTIVES

The authors performed this meta-analysis to more robustly evaluate associations between polymorphisms in the IL-1 gene and the risk of RA/SLE.

METHODS

MEDLINE, Embase, Web of Science, Wanfang, VIP, and CNKI were systematically searched for eligible studies, and 34 relevant studies were finally selected to be eligible for inclusion.

RESULTS

We found that IL-1A +4845G/T polymorphism was significantly associated with the risk of RA in the overall population (dominant comparison: p = 0.02; overdominant comparison: p = 0.05; allele comparison: p = 0.04), whereas IL-1B +3954C/T polymorphism was significantly associated with the risk of RA in the overall population (overdominant comparison: p = 0.03; allele comparison: p = 0.01) and Asians (recessive comparison: p = 0.007; allele comparison: p = 0.002). In addition, we found that IL-1A -889C/T polymorphism was significantly associated with the risk of SLE in Caucasians (allele comparison: p = 0.04), IL-1B -31T/C polymorphism was significantly associated with the risk of SLE in the overall population (recessive comparison: p = 0.04), and IL-1B -511C/T polymorphism was significantly associated with the risk of SLE in Asians (recessive comparison: p = 0.01; allele comparison: p = 0.03).

CONCLUSIONS

This meta-analysis suggests that IL-1A +4845G/T and IL-1B +3954C/T polymorphisms may influence the risk of RA, whereas IL-1A -889C/T, IL-1B -31T/C, and IL-1B -511C/T polymorphisms may influence the risk of SLE.

Pro-inflammatory cytokine response pre-dominates immuno-genetic pathway in development of rheumatoid arthritis

Rheumatoid arthritis (RA) is a crucial inflammatory joint disease characterized by loss of self-tolerance and severe cartilage loss, autoimmune, and subchondral bone erosions. Cytokines are the key regulators of inflammatory responses. Homeostatic imbalances in pro- and anti-inflammatory cytokine activities can result in pathogenic inflammatory reactions. These imbalances could be initiated by environmental factors but the ability to define the threshold of environmental impact relies on the genetic background of the pro- and anti-inflammatory cytokines. To address this a case-control association study was carried out in 429 individuals from Malayalam speaking ethnic population from South India. Functionally relevant SNPs from IL-10, IL-6, IL-1β and IL-1RN were genotyped using PCR -RFLP and sequencing. Meta-analysis was performed for the associated variants of IL-10, IL-1β. Significant association with RA was observed with IL-1β rs1143634, rs1143627, IL-10 rs1800896, IL-6 rs1800796, rs1800797. The associated SNPs are likely to impact transcriptional activity of a gene. Meta-analysis with global populations also provide evidence that IL-10 and IL-1β could be a global marker for RA. The functional significance of associated risk variants of IL-1β and IL-6 indicate increased production of the pro-inflammatory cytokines while IL-10 risk allele suggest reduced production of anti- inflammatory cytokines. The study concludes that increased production of pro-inflammatory cytokines and reduced production of anti- inflammatory cytokines may influence the Th1/Th2 equilibrium resulting in a triggering of Th1 mediated inflammatory responses in development of RA.

The Association Between Interleukin-6 Promoter Polymorphisms and Rheumatoid Arthritis by Ethnicity: A Meta-Analysis of 33 Studies

OBJECTIVE

We performed a meta-analysis to determine the effect Interleukin-6 (IL-6) promoter polymorphism (-174 G>C, -572 G>C, and -597 G>A) have on the development rheumatoid arthritis (RA) by ethnicity.

MATERIAL AND METHODS

PubMed, EBSCO, LILACS, and Scopus databases were searched for studies exploring the association between any IL6 polymorphisms and RA until November 2018. Genotype distributions were extracted and, depending on the level heterogeneity, determined by the ψ2-based Q test and the Inconsistency Index (I2), fixed-effects or random-effects models were used to calculate pooled odds ratios (ORs) with 95% confidence intervals (95%CIs) for the heterozygous, homozygous, dominant, recessive, and allelic genetic models.

RESULTS

From 708 identified publications, 33 were used in this analysis. For the -174 polymorphism, Asians (ORheterozygous=7.57, 95%CI: 2.28-25.14, ORhomozygous=5.84, 95%CI: 2.06-16.56, ORdominant=7.21, 95%CI: 2.30-22.63, ORrecessive=5.04, 95%CI: 1.78-14.28, ORallelic=6.60, 95%CI: 2.26-19.28, p<.05) and Middle East countries (ORheterozygous=2.30, 95%CI: 1.10-4.81, ORdominant=2.27, 95%CI: 1.22-4.22, ORallelic=2.29, 95%CI: 1.24-4.23, p<.05) were associated with a significant risk of developing RA. Whereas, for Latinos, the C-allele was associated with a benefit (ORhomozygous=0.26, 95%CI: .08-.82, ORrecessive=.25, 95%CI: .08-.80, p<.05). For the -572 polymorphism, Asians demonstrated a significant association for the homozygous and recessive genetic models (8 studies, ORhomozygous=1.56, 95%CI: 1.16-2.09, ORrecessive=1.63, 95%CI: 1.08-2.45, p<.05). For the -597 polymorphism, no association was observed.

CONCLUSIONS

Here, the -174 G>C polymorphism increased the risk of developing RA in Asians and Middle East populations. Interestingly, for Latinos, the polymorphism was associated with a benefit. For the -572 polymorphism, only the Asian population showed an increased risk of developing RA for the CC genotype.

IL1β, IL18, NFKB1 and IFNG gene interactions are associated with severity of rheumatoid arthritis: A pilot study

Rheumatoid arthritis (RA) is an autoimmune disease which can lead to progressive and functional disability. Literature data suggest that some inflammatory proteins are dysregulated in RA patients and its genetic polymorphisms may contribute to the aetiology and pathogenesis of disease in different ethnic groups. Polymorphisms in IL1β, IL18, NFKB1 and IFNG genes were studied in different populations with RA, but the analysis indicated contradictory results. Thereby, we hypothesised that polymorphisms in these genes could have a combined effect on susceptibility to and severity of disease. We evaluated the +3953 C/T IL1β (rs1143634), -137 G/C IL18 (rs187238), -94 ins/del ATTG NFKB1 (rs28362491) and +874 T/A IFNG (rs2430561) polymorphisms in the northeastern Brazilian population. Peripheral blood samples were collected and DNA extraction was conducted. The polymorphisms were evaluated by RFLP and ARMS-PCR. An association was observed in rs1143634 which showed a protective effect against development of RA in carriers of the T allele (OR = 0.58; 95% CI 0.36-0.92; p = .020). In addition, we found an association among genotypes of the rs1143634 with the HAQ index (p = .021) and rs2430561 with DAS28 (p = .029) and CDAI (p = .029). In relation to combined effects of these SNPs (C/C to rs1143634, G/G to rs187238, I/I to rs28362491 and AA to rs2430561) we found a significant association with decreased functional disability (HAQ index p < .001) and ESR (p = .034), indicating a lower disease activity in carriers of these genotypes. GLM analysis confirmed these associations (HAQ (F = 5.497; p < .001) and ESR (F = 2.727; p = .032)). Our analysis indicated that in the studied population +3953 C/T IL-1β (rs1143634), -137 G/C IL-18 (rs187238), -94 ins/del ATTG NFKB1 (rs28362491) and +874 T/A IFNG (rs2430561) polymorphisms can together contribute to RA severity although they do not individually influence the disease.

CCL5 and related genes might be the potential diagnostic biomarkers for the therapeutic strategies of rheumatoid arthritis

OBJECTIVE

Rheumatoid arthritis (RA) is a common disease of rheumatic diseases. The aim of this study was to identify gene signatures in RA and uncover their potential mechanisms.

METHOD

Gene expression profiles of GSE1919, GSE55235, GSE55457, and GSE77928 were downloaded from GEO database. The above four series contained 76 samples, including 44 RA patients and 32 normal controls. The gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed, and protein-protein interaction (PPI) network of the differentially expressed genes (DEGs) was constructed by Cytoscape software.

RESULTS

Up-regulated DEGs were significantly enriched in biological processes, including immune response, positive regulation of immune system process and regulation of immune system process, while down-regulated DEGs were significantly enriched in biological processes, including response to oxygen-containing compound, cellular lipid metabolic process, and lipid metabolic process. KEGG pathway analysis showed the up-regulated DEGs were enriched in cytokine-cytokine receptor interaction, chemokine signaling pathway, and primary immunodeficiency. The 104 hub genes, which were significantly differently expressed between patients and normal controls in at least two datasets, were identified from the PPI network, and subnetworks revealed that these genes were involved in significant pathways, including cytokine-cytokine receptor interaction, chemokine signaling pathway, and primary immunodeficiency.

CONCLUSION

The present study indicated that the identified DEGs and hub genes promote our understanding of molecular mechanisms underlying the development of RA, such as C-C motif chemokine 5 (CCL5), might have a negative impact in the development of RA. CCL5 and its related genes might be the potential diagnostic biomarkers for the therapeutic strategies of RA.

Interleukin10-1082 A/G polymorphism: Allele frequency, correlation with disease markers, messenger RNA and serum levels in North Indian rheumatoid arthritis patients

BACKGROUND

Rheumatoid arthritis (RA) is an autoimmune inflammatory disorder of unknown etiology. IL-10 stimulates B cell survival and is involved in antibody isotype switching. The serum IL-10 levels are increased in RA patients. Ethnicity influences polymorphisms in cytokine genes. Therefore, this study was designed to explore possible association, if any, between polymorphism of IL10-1082 A/G, serum cytokine levels, inflammatory markers and gene expression in RA patients of North India.

METHODOLOGY

A total of 187 RA patients classified according to American college of rheumatology 2010 criteria and 214 controls were included in the study. Levels of serum IL-10 and inflammatory markers were estimated by ELISA. PCR-RFLP was used to analyze IL10-1082 A/G polymorphism. Quantitative real time PCR was used to measure the mRNA expression of IL-10 gene.

RESULTS

The serum inflammatory markers were significantly higher in RA patients. Circulating IL-10 levels were positively and significantly correlated with RF (r = 0.28), anti-CCP (r = 0.26), CRP (r = 0.17) and mRNA expression levels (r = 0.59) among RA patients. Homozygous mutant variant (GG) and heterozygous mutant variant (AG) were associated with patients of RA (OR = 2.87 and 1.55, p < 0.05) as compared to controls. The association still persisted when the heterozygous and homozygous mutants (AG + GG) were clubbed together (OR = 1.67, p < 0.05). The mRNA expression of IL-10 was found to be 3.63 folds higher (housekeeping gene, β-actin) and 2.42 folds higher (housekeeping gene, 18S rRNA) in RA patients as compared to controls.

CONCLUSION

The results indicate that IL10-1082 A/G polymorphism is associated with genetic susceptibility/predisposition to RA in North Indian population.

Association of polymorphic variants in IL1B gene with secretion of IL-1β protein and inflammatory markers in north Indian rheumatoid arthritis patients

The proinflammatory cytokine interleukin-1beta (IL-1β) is a key mediator of inflammation which affects cell proliferation and differentiation. IL-1β is considered to contribute to the pathophysiology of rheumatoid arthritis (RA). Polymorphisms in cytokine genes are highly influenced by ethnicity. Hence, in this study polymorphism of the IL1B-511(C/T) within promoter region was analyzed by using polymerase chain reaction-restriction fragment length Polymorphism (PCR-RFLP) in 187 RA patients and 214 controls. The prevalence of different genotypes and allelic frequency distribution was compared in RA patients and controls. Levels of inflammatory markers and serum levels of IL-1β were estimated by ELISA The serum inflammatory markers levels were significantly higher in RA patients as compared to controls (RF=127.3±21.3U/mL, Anti-CCP=17.8±8.3U/mL, CRP=17.86±7.1mg/L and IL-1β=21.25±4.19pg/mL in RA patients p<0.01). The frequency of heterozygous mutant (C/T) and homozygous mutant (T/T) variants were significantly higher in RA patients as compared to controls and the odds ratios by logistic regression were (OR=2.2, p<0.001) and (OR=3.21, p<0.01) respectively. The association persisted on combining the heterozygous mutant and homozygous mutant (CT+TT) together as compared to controls (OR=2.39; p<0.001). Positive and significant (p<0.05) correlation of circulating IL-1β levels with RF (r=0.232), anti-CCP (r=0.207) and CRP (r=0.166) among RA patients were found. The levels of anti-CCP were significantly higher in homozygous mutant variants (TT) as well as the heterozygous mutant variants (C/T) in comparison to the wild variants (CC) (p<0.01). The results of this study reveal that mutant allele (T) of IL1B-511 promoter SNP tends to be associated with elevated anti-CCP and IL-1β levels as observed in RA patients and hence disease susceptibility.

Association of interleukin-1 family gene polymorphisms with juvenile idiopathic arthritis in Iranian population

BACKGROUND

Cytokines, including interleukin-1 (IL-1), seem to contribute towards the pathogenesis of juvenile idiopathic arthritis (JIA), so this study was designed to evaluate the associations of IL-1 gene cluster and IL-1 receptor (IL-1R) gene single nucleotide polymorphisms (SNPs) with JIA proneness in Iranian population.

MATERIALS AND METHODS

Genomic DNA of 55 Iranian patients with JIA and 140 controls were extracted and typed for IL-1α gene at position -889, IL-1β gene at positions -511 and +3962, IL-1R gene at position Pst-I 1970, and interleikin-1 receptor antagonist (IL-1Ra) gene at position Mspa-I 11100, using polymerase chain reaction with sequence-specific primers method, and compared between patients and controls.

RESULTS

The CC genotype of IL-1Ra at Mspa-I 11100 position was found to be more frequent in patients with JIA compared to healthy individuals (P=0.03), although the CT genotype at the same position was significantly higher in the control group in comparison with patients with JIA (P=0.02). No significant differences were observed between the two groups of case and control for IL-1α (-889 C/T), IL-1β (-511 C/T and +3962 C/T) and IL-1R (Pst-1 1970 C/T).

CONCLUSION

The results of the present investigation suggest that certain IL-1Ra gene variants are associated with individuals' susceptibility to JIA. Nevertheless, further studies are required to establish the results of the current study.

The -174G/C Interleukin-6 Gene Promoter Polymorphism as a Genetic Marker of Differences in Therapeutic Response to Methotrexate and Leflunomide in Rheumatoid Arthritis

Objective. To evaluate the association of -174G/C IL-6 polymorphism with failure in therapeutic response to methotrexate (MTX) or leflunomide (LEF). This prospective, observational cohort included 96 Mexican-Mestizo patients with moderate or severe rheumatoid arthritis (RA), initiating MTX or LEF, genotyped for IL-6 -174G/C polymorphism by PCR-RFLP. Therapeutic response was strictly defined: only if patients achieved remission or low disease activity (DAS-28 < 3.2). Results. Patients with MTX or LEF had significant decrement in DAS-28 (p < 0.001); nevertheless, only 14% and 12.5% achieved DAS-28 < 3.2 at 3 and 6 months. After 6 months with any of these drugs the -174G/G genotype carriers (56%) had higher risk of therapeutic failure compared with GC (RR: 1.19, 95% CI: 1.07-1.56). By analyzing each drug separately, after 6 months with LEF, GG genotype confers higher risk of therapeutic failure than GC (RR = 1.56; 95% CI = 1.05-2.3; p = 0.003), or CC (RR = 1.83; 95% CI = 1.07-3.14; p = 0.001). This risk was also observed in the dominant model (RR = 1.33; 95% CI = 1.03-1.72; p = 0.02). Instead, in patients receiving MTX no genotype was predictor of therapeutic failure. We concluded that IL-6 -174G/G genotype confers higher risk of failure in therapeutic response to LEF in Mexicans and if confirmed in other populations this can be used as promissory genetic marker to differentiate risk of therapeutic failure to LEF.

Association of IL-1β +3953 C and HLA-DRB1*15 with Coronary Artery and Rheumatic Heart Diseases in South India

Among the various candidate genes predisposing for cardiovascular diseases, HLA-DRB1* and IL-1β +3953C/T alleles have been implicated repeatedly. To test these in South India, we carried out a case control study of 323 Coronary Artery Disease (CAD) patients, 56 Rheumatic Heart Disease (RHD) patients and 254 endemic controls. The polymorphisms were studied by PCR - SSP and ARMS-PCR methods and results analyzed for various clinical and demographic parameters. In CAD, HLA-DRB1*14 allele showed significant predisposition (OR: 2.19; 95% CI: 1.04-4.58; p value=0.023), particularly in male patients (OR: 4.07; 95% CI: 1.20-13.81; p value=0.01) and further in males with Triple Vessel Disease (OR: 5.49; 95% CI: 1.45-20.60; p value=0.007). On the other hand, HLA-DRB1*15 predisposed for RHD (OR: 3.56; 95% CI: 1.87-6.78; p value=0.001) in both the genders. Population stratification showed this higher risk association in Vanniyar caste (OR: 5.00; 95% CI: 1.27-19.59; p value=0.022). Among the IL1-β +3953C/T polymorphism, the ancestral allele 'C' showed a significant high risk association with CAD (OR: 1.83; 95% CI: 1.24-2.70; p value=0.001), particularly in Mudaliar (OR: 6.07; 95% CI: 1.77-20.74; p value=0.003; AF=0.7) and Vanniyar castes (OR: 3.67; 95% CI: 0.92-14.57; p value=0.05; AF=0.660). Two different cardiac ailments studied, RHD & CAD thus showed varied associations in this South Indian cohorts. RHD having an infectious aetiology shared a HLA-DRB1*15 high risk association, while HLA-DRB1*14 and IL-1β +3953C predisposed for CAD, an inflammatory disorder, reiterating the diverse genetic predisposition of the two cardiac ailments studied.

Circulating interleukin-6 and rheumatoid arthritis: A Mendelian randomization meta-analysis

Interleukin-6 (IL-6), as a pleiotropic cytokine, has been demonstrated to be closely associated with the pathogenisis of rheumatoid arthritis (RA). However, whether this association is causal or not remains unclear, because of the multifactorial role of IL-6 and related confounding factors. We aimed to evaluate the causal relevance between circulating IL-6 levels and the risk of RA through meta-analytical Mendelian randomization approach. IL-6 gene -174G/C variant was selected as an instrument in this Mendelian randomization meta-analysis. Article identification and data collection were conducted in duplicate and independently by 2 authors. The STATA software was used for data analysis. In total, 15 and 5 articles on the association of the -174G/C variant with RA risk and circulating IL-6 level, respectively, were included. The overall analysis showed that C allelic and GC+CC genotype were significantly with 1.59-fold (95% CI: 1.19-2.14) and 1.63-fold (95% CI: 1.17-2.26) increased risk of developing RA, respectively. Asian populations showed stronger association with 4.55-fold (95% CI: 1.62-12.75), 1.84-fold (95% CI: 1.13-2.99), and 4.69-fold (95% CI: 1.68-13.14) increased RA risk in carriers of -174C allelic, CC, and GC+CC genotype, respectively. Carriers of GC+CC genotype showed significant reduction in the circulating IL-6 level compared with GG carriers (WMD = -0.77; 95% CI: -1.16 to -0.38; P = 0.000) in overall populations. Mendelian randomization presented 6% and 22% increased risk of RA with 0.1 pg/mL reduction of circulating IL-6 level in overall and Asian populations, respectively. This Mendelian randomization meta-analysis demonstrated that the long-term genetically reduced circulating IL-6 level might be causally related to a higher risk of RA, especially in Asian populations.

Significant impact of IL-6 -174G/C but inverse relation with -634 C/G polymorphism in patients with non-small cell lung cancer in Kashmiri population

To study the possible role of proinflammatory interleukin 6 -174 G>C (rs 1800795) and -634 C>G (rs 1800796) polymorphism in the pathogenesis of non-small cell lung cancer (NSCLC). A total of 190 NSCLC patients and 200 healthy controls were evaluated for polymorphic analysis of -174 G/C and -634 C/G by PCR-RFLP followed by DNA sequencing. A significant association was observed in the genotypic and allelic distribution of IL-6 -174 G/C in the NSCLC group as compared to control group [OR = 2.7 (1.77-4.11), p < 0.0001]. Smokers with the -174C allele were found to be significantly associated with NSCLC (p = 0.01), while 634C/G SNP showed an inverse relation [OR-0.4, p < 0.0001]. The present investigation revealed a significant association of the IL6 -174 G/C gene promoter polymorphism with NSCLC, and thus, the IL-6 -174G/C genotype can be considered as one of the biological markers in the etiology of NSCLC.