Single nucleotide polymorphisms in the tumor necrosis factor-alpha gene promoter region alter the risk of psoriasis vulgaris and psoriatic arthritis: a meta-analysis

Biomarkers in Psoriasis: The Future of Personalised Treatment

Psoriasis is a chronic and complex immune-mediated papulosquamous disease affecting almost 2% of the world population. The interaction between a genetically predisposed individual and environmental triggers leads to a vicious cycle involving autoreactive T cells, dendritic cells, keratinocytes and dermal cells. Up to 40% of the psoriasis cases develop disabling psoriatic arthritis and an equal number of patients also tend to develop metabolic syndrome as well as cardiovascular comorbidities; hence, this is no more considered to be a disease limited to skin only. Being a systemic disease, there is an urgent need to develop potential biomarkers for the assessment of disease severity, prediction of outcome of the therapeutic intervention and association with various systemic comorbidities. Diverse genetic markers not only function as predictors of diseases pathogenesis, but also help to predict development of psoriasis and psoriatic arthritis. Personalised medicine is customising the therapeutic needs of a psoriasis patient and improving the outcome as per the hints we receive from the various biomarkers. This review deals with the list of potential biomarkers proposed to be useful in psoriasis, though there is limited data validating their routine use in clinical practice and the progress so far made in the field of precision medicine for psoriasis.

Association between tumor necrosis factor-alpha polymorphisms (rs361525, rs1800629, rs1799724, 1800630, and rs1799964) and risk of psoriasis in studies following Hardy-Weinberg equilibrium: A systematic review and meta-analysis

Objective

Psoriasis is a disease with an immunogenetic background in which cytokines have important effects on its prevalence and incidence. The present meta-analysis evaluated the relationship between tumor necrosis factor-alpha (TNF-α) polymorphisms (rs361525, rs1800629, rs1799724, 1800630, and rs1799964) and psoriasis risk in studies following Hardy-Weinberg equilibrium (HWE).

Materials and methods

Four databases were searched to retrieve relevant studies reporting the distributions of TNF-α polymorphisms in psoriasis cases compared to controls. The effect sizes were the 95% confidence intervals (CIs) and odds ratios (ORs). Subgroup analysis, sensitivity analyses, publication bias, trial sequential analysis (TSA), and meta-regression were performed on the initial pooled results of TNF-α polymorphisms.

Results

Thirty-six articles with 71 studies were included in the meta-analysis (twenty-six: rs361525, twenty-seven: rs1800629, nine: rs1799724, four: 1800630, and five: rs1799964). The pooled ORs for -238 G/A rs361525 polymorphism were 2.33 (p < 0.00001), 2.79 (p < 0.0001), 2.35 (p < 0.00001), 2.44 (p < 0.00001), and 2.45 (p < 0.00001), as well as 1.57 (p < 0.00001), 1.98 (p = 0.01), 1.61 (p < 0.00001), 1.64 (p < 0.00001), and 1.79 (p < 0.00001) for -857 C/T rs1799724 polymorphism in allelic, homozygous, heterozygous, dominant, and recessive models, respectively. Ethnicity, psoriasis type, and sample size affected the pooled results of rs361525, rs1800629, and rs1799724 polymorphisms. Based on TSA, there were just sufficient cases for -238 G/A rs361525 polymorphism in five genetic models and -857C/T rs1799724 polymorphism in allelic, heterozygous, and dominant models.

Conclusions

The A allele and GA and GG genotypes of -238 G/A rs361525 polymorphism and T allele, TT and CT genotypes of -857C/T rs1799724 polymorphism were related to increased risks in psoriasis cases. Well-designed studies (with no deviation from HWE in controls) with more cases are recommended in the future.

Cognitive Process of Psoriasis and Its Comorbidities: From Epidemiology to Genetics

Psoriasis (PsO) is a chronic inflammatory skin disease that affects approximately 2% of the population all over the world. Comorbidities of PsO have increasingly garnered more interest in the past decades. Compared with the normal population, the incidences of comorbidities are higher among patients with PsO. In the last 20 years, researchers have focused on studying the genetic components of PsO, and genetic associations between PsO and its comorbidities were elucidated. This review provides an in-depth understanding and summarization of the connection between PsO and its comorbidities from the perspectives of epidemiology and genetics. Further understanding of PsO and its comorbidities will promote research on the pathogenesis, drug development, novel therapy methods, and personalized and precision treatment of PsO and its comorbidities.

Tumor Necrosis Factor-α 308 G/A polymorphism and psoriasis risk: A pooled analysis in different populations

More and more researches have been carried out on the association between the tumor necrosis factor-α (TNF-α) 308 G/A polymorphism and psoriasis, however, controversial results have emerged in these studies. This meta-analysis was performed to quantitatively clarify the relationship between TNF-α 308 G/A polymorphism and the risk of psoriasis in different populations. Databases of PubMed, Springer Link, Ovid, Chinese Wanfang Data Bases, Chinese National Knowledge Infrastructure and Chinese Biology Medicine were investigated until June 2019. The association between the TNF-α 308 G/A polymorphism and psoriasis was evaluated by calculating the pooled odds ratio (OR) and 95% confidence intervals (CIs). A total of 26 studies including 3657 patients and 3197 controls were screened out. In the overall population, the pooled results showed a reduced psoriasis risk with the TNF-α 308 G/A polymorphism (A vs G: OR = 0.77, 95% CI = 0.67-0.89; AA+GA vs GG: OR = 0.72, 95% CI = 0.61-0.86). In the subgroup analysis stratified by geographic locations, the TNF-α 308 G/A polymorphism was significantly associated with a reduced risk of psoriasis in Germany (A vs G: OR = 0.67, 95% CI = 0.57-0.78; AA+GA vs GG: OR = 0.62, 95% CI = 0.52-0.75), as well as in China (AA+GA vs GG: OR = 0.71, 95% CI = 0.52-0.98) and Poland (A vs G: OR = 0.61, 95% CI = 0.38-0.97; AA+GA vs GG: OR = 0.59, 95% CI = 0.35-0.99). This study indicated a significantly reduced psoriasis risk associated with the TNF-α 308 G/A polymorphism in Germans, as well as in Chinese and Poles populations compared with other populations. Ethnicity and geographic locations probably play a pivotal role in the genetic association of psoriasis.

Polymorphism in Organic Anion-Transporting Polypeptide Gene Related to Methotrexate Response in Rheumatoid Arthritis Treatment

BACKGROUND

Methotrexate (MTX) is still the first-choice drug for the treatment of rheumatoid arthritis (RA). In Japan, MTX doses of up to 16 mg/week were approved in 2011. In this study, we aimed to identify the gene polymorphisms that can predict therapeutic effects of MTX in Japanese patients in current clinical settings.

METHODS

This study involved 171 patients with RA (all Japanese nationals, age 63.5±10.0 years) who had been administered MTX. The analyzed polymorphisms included 82 single nucleotide polymorphisms (SNPs) involved in the MTX pharmacological pathway or in the pathogenesis of RA. Responders were patients who showed high sustained remission or low disease activity with MTX or conventional disease-modifying anti-rheumatic drugs (DMARDs) treatment beyond 6 months. Non-responders were patients who showed moderate or high disease activity, who were prescribed biological DMARDs. A logistic model was constructed with Responder/Non-responder as the target variable, and minor allele frequency was set as an explanatory variable.

RESULTS

None of the 82 SNPs targeted for analysis met the Bonferroni significance threshold of 6.098×10^-4. However, we identified SLCO1B1 rs11045879 as an SNP that might yield significant results if the number of patients were to be increased (P=0.015).

CONCLUSIONS

The rs11045879 minor allele in the SLCO1B1 gene is a potential predictor of non-responders to MTX treatment among Japanese RA patients. In future collaborative research, we will investigate whether the association with SLCO1B1 polymorphism is significant by performing statistical analysis with a larger study population.

Association of TNF, IL12, and IL23 gene polymorphisms and psoriatic arthritis: meta-analysis

BACKGROUND

Psoriatic arthritis (PsA) is a chronic skin and joint condition that considerably affects patient quality of life. Several studies have demonstrated different associations of genetic polymorphisms in the pathogenic process of PsA. Therefore, we conducted a meta-analysis to estimate the effect of polymorphisms in the cytokines TNF, IL12B, IL23A, and IL23R on PsA risk.

METHODS

We screened 1,097 abstracts and identified 14 relevant studies published between January 2007 and December 2017. A systematic search was conducted in PubMed, Web of Knowledge and Scopus databases. Meta-analyses were performed for the comparisons of alleles and multiple genetic models.

RESULTS

Among the cytokines studied, we found 17 polymorphisms that were the most investigated. The association to PsA was observed in the presence of polymorphisms: TNF-238 G > A (rs361525), -308 G > A (rs1800629), and -857 C > T (rs1799724); IL12B C > G (rs6887695) and A > C (rs3212227); IL23A A > G (rs2066808) and IL23R G > A (rs11209026).

CONCLUSION

Our findings suggest that these variant cytokine genes may strongly influence the immunological response of PsA.

Genetic polymorphisms associated with psoriasis and development of psoriatic arthritis in patients with psoriasis

Background

Psoriasis (PsO) is a chronic inflammatory disease with predominantly cutaneous manifestations. Approximately one third of patients with PsO develop psoriatic arthritis (PsA), whereas the remaining proportion of patients has isolated cutaneous psoriasis (PsC). These two phenotypes share common immunology, but with different heredity that might in part be explained by genetic variables.

Methods

Using a candidate gene approach, we studied 53 single nucleotide polymorphisms (SNPs) in 37 genes that regulate inflammation. In total, we assessed 480 patients with PsO from DERMBIO, of whom 151 had PsC for 10 years or more (PsC10), 459 patients with PsA from DANBIO, and 795 healthy controls. Using logistic regression analysis, crude and adjusted for age and gender, we assessed associations between genetic variants and PsO, PsC10, and PsA, as well as associations between genetic variants and development of PsA in PsO.

Results

Eleven polymorphisms in 10 genes were nominally associated with PsO and/or PsC and/or PsA (P < 0.05). After correction for multiple testing with a false discovery rate of 5%, two SNPs remained significant: TNF (rs361525) was associated with PsO, PsC10, and PsA; and IL12B (rs6887695) was associated with PsO.

Conclusion

Among a cohort of Danish patients with moderate-to-severe psoriasis, two SNPs in the IL12B and TNF genes were associated with susceptibility of psoriasis. None of the SNPs were specifically associated with isolated cutaneous psoriasis or psoriatic arthritis.

Profile of Tumour Necrosis Factor Alpha -308 G/A Gene Polymorphism in Psoriatic Patients in Karnataka, India

INTRODUCTION

Tumour necrosis factor-alpha (TNFα) gene -308G/A polymorphism (rs1800629) are associated with psoriasis in several populations worldwide. Presently, there is no literature on the status of this polymorphism in the South Indian population.

AIM

To determine the profile of TNFα -308G/A polymorphism among psoriatic patients.

MATERIALS AND METHODS

This case-control study involved 74 patients with Psoriasis Vulgaris (PsV) and 74 age and gender matched healthy individuals. Patients were recruited from the Department of Dermatology of R.L. Jalappa Hospital and Research Center, Tamaka, Kolar, Karnataka, India, from March 2014 to March 2016. TNFα -308G/A polymorphism was genotyped by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) method.

RESULTS

The frequency of TNFα -308A allele 7.4% among psoriatic and 8.8% among non-psoriatic individuals. The difference was not statistically significant (p=0.82).

CONCLUSION

Our results indicate that TNFα gene -308G/A polymorphism is not a significant marker for the risk of developing PsV among South Indian (Karnataka) psoriatic patients.

Tumor necrosis factor alpha gene promoter -238G/A polymorphism increases the risk of psoriasis vulgaris in Indian patients

BACKGROUND

Tumor necrosis factor alpha (TNFα) gene -238G/A polymorphism (rs361525) is associated with psoriasis in several populations worldwide. To the best of our knowledge, there is no information about this polymorphism in Indian psoriatic patients. This study was undertaken to fill the gap in knowledge.

METHODS

This case-control study involved 72 patients with psoriasis vulgaris (PsV) and 72 age and gender matched healthy individuals. TNFα -238G/A polymorphism was genotyped by PCR-RFLP method.

RESULTS

TNFα -238A allele was 5 times commoner in PsV patients than in the control group (P = 4.1 × 10^-7 ; odds ratio [OR] = 6.5 [0.95 CI: 2.9-14.6]). Distribution of the genotypes in the two groups showed statistically significant difference in dominant genetic model (P = 2.3 × 10^-7 ) and not in recessive genetic model (P = 2.5 × 10^-1 ). Odds ratio for the occurrence of -238A genotype in PsV patients was 8.8 (0.95 CI: 3.5-20.2). The association showed no major difference when PsV patients were subgrouped into type I and type II categories and tested separately. Subgroup analysis on the basis of disease severity showed higher association with the moderate-severe subgroup (P = 2.4 × 10^-9 , OR 15.4 [0.95 CI: 5.8-41.0]) than with mild subgroup (P = 1.3 × 10^-2 , OR 3.8 [0.95 CI: 1.3-10.9]).

CONCLUSIONS

Our results indicate that TNFα gene -238G/A polymorphism increases the risk of developing psoriasis vulgaris among Indians. Also, the data show that severity and not the type affects the strength of association in this population.

Factors affecting response to biologic treatment in psoriasis

Psoriasis is a chronic, immune-mediated inflammatory skin disease, affecting approximately 2-4% of the population in western countries. Patients with a more severe form of the disease are typically considered for systemic therapy, including biologics. In spite of the overall superiority of biologic agents, the treatment response may differ substantially among individual patients. As with other medical conditions, a range of factors contribute to response heterogeneity observed in psoriasis. Proper identification of these factors can significantly improve the therapeutic decisions. This review focuses on potential genetic and nongenetic factors that may affect the treatment response and outcomes in patients with psoriasis.

A metaanalysis of the increased risk of rheumatoid arthritis-related pulmonary disease as a result of serum anticitrullinated protein antibody positivity

OBJECTIVE

An inconsistent association has been reported between the serum anticitrullinated protein antibodies (ACPA) level and rheumatoid arthritis (RA)-related pulmonary disease risk. We conducted a metaanalysis to reveal the association between them.

METHODS

An electronic search was performed in PubMed, ScienceDirect, and SpringerLink databases for studies published up to August 2013. The distributions of the serum ACPA level in cases and controls were obtained from eligible studies. The risk of RA-related pulmonary disease associated with serum ACPA positivity was estimated by OR and 95% CI. According to the heterogeneity results, a fixed-effects model or a random-effects model was used to calculate the pooled OR. Publication bias and sensitivity analyses were conducted.

RESULTS

Overall, 243 patients with RA-related pulmonary disease and 1442 RA controls were included in the metaanalysis. The results showed that the pooled OR was 2.621 (95% CI, 1.561-4.403, p < 0.001) for the increased risk of RA-related pulmonary disease due to the serum ACPA positivity. In the white population subgroup, an increased OR was 3.453 (95% CI 1.798-6.630, p < 0.001), whereas no association was found in the Asian population subgroup. Additionally, we further revealed that serum ACPA positivity indicated a higher risk for interstitial lung disease (ILD) and interstitial pulmonary fibrosis (IPF) among patients with RA (OR 4.679, 95% CI 2.071-10.572, p < 0.001). The heterogeneity, publication bias, and sensitivity analyses had no statistical significance in any group.

CONCLUSION

To our knowledge, this is the first metaanalysis to reveal that serum ACPA positivity is highly associated with the risk of RA-related pulmonary disease, particularly in RA-related ILD and IPF.