The relationship between tumour necrosis factor (TNF)-α promoter andIL12B/IL-23Rgenes polymorphisms and the efficacy of anti-TNF-α therapy in psoriasis: a case-control study

The Role of Genetics on Psoriasis Susceptibility, Comorbidities, and Treatment Response

This review highlights advances made in psoriasis genetics, including findings from genome-wide association studies, exome-sequencing studies, and copy number variant studies. The impact of genetic variants on various comorbidities and therapeutic responses is discussed.

The Association between Genetics and Response to Treatment with Biologics in Patients with Psoriasis, Psoriatic Arthritis, Rheumatoid Arthritis, and Inflammatory Bowel Diseases: A Systematic Review and Meta-Analysis

Genetic biomarkers could potentially lower the risk of treatment failure in chronic inflammatory diseases (CID) like psoriasis, psoriatic arthritis (PsA), rheumatoid arthritis (RA), and inflammatory bowel disease (IBD). We performed a systematic review and meta-analysis assessing the association between single nucleotide polymorphisms (SNPs) and response to biologics. Odds ratio (OR) with 95% confidence interval (CI) meta-analyses were performed. In total, 185 studies examining 62,774 individuals were included. For the diseases combined, the minor allele of MYD88 (rs7744) was associated with good response to TNFi (OR: 1.24 [1.02-1.51], 6 studies, 3158 patients with psoriasis or RA) and the minor alleles of NLRP3 (rs4612666) (OR: 0.71 [0.58-0.87], 5 studies, 3819 patients with RA or IBD), TNF-308 (rs1800629) (OR: 0.71 [0.55-0.92], 25 studies, 4341 patients with psoriasis, RA, or IBD), FCGR3A (rs396991) (OR: 0.77 [0.65-0.93], 18 studies, 2562 patients with psoriasis, PsA, RA, or IBD), and TNF-238 (rs361525) (OR: 0.57 [0.34-0.96]), 7 studies, 818 patients with psoriasis, RA, or IBD) were associated with poor response to TNFi together or infliximab alone. Genetic variants in TNFα, NLRP3, MYD88, and FcRγ genes are associated with response to TNFi across several inflammatory diseases. Most other genetic variants associated with response were observed in a few studies, and further validation is needed.

Gene Ontology Analysis Highlights Biological Processes Influencing Responsiveness to Biological Therapy in Psoriasis

Psoriasis is a chronic, immune-mediated and inflammatory skin disease. Although various biological drugs are available for psoriasis treatment, some patients have poor responses or do not respond to treatment. The aim of the present study was to highlight the molecular mechanism of responsiveness to current biological drugs for psoriasis treatment. To this end, we reviewed previously published articles that reported genes associated with treatment response to biological drugs in psoriasis, and gene ontology analysis was subsequently performed using the Cytoscape platform. Herein, we revealed a statistically significant association between NF-kappaB signaling (p value = 3.37 × 10-9), regulation of granulocyte macrophage colony-stimulating factor production (p value = 6.20 × 10-6), glial cell proliferation (p value = 2.41 × 10-5) and treatment response in psoriatic patients. To the best of our knowledge, we are the first to directly associate glial cells with treatment response. Taken together, our study revealed gene ontology (GO) terms, some of which were previously shown to be implicated in the molecular pathway of psoriasis, as novel GO terms involved in responsiveness in psoriatic disease patients.

Impact of Single Nucleotide Polymorphisms of the Promoter of the TNF Gene on Adalimumab Treatment Responses in Hidradenitis Suppurativa

BACKGROUND

Results of randomized clinical trials show great variation in response to treatment with adalimumab (ADA) in hidradenitis suppurativa (HS). This varied response may be associated with genetic polymorphisms.

OBJECTIVES

The aim of the study was to study the association between carriage of single nucleotide polymorphisms (SNPs) in the promoter of the tumor necrosis factor (TNF) gene and their response to ADA.

METHODS

Patients with moderate to severe HS who received ADA treatment for at least 12 weeks were enrolled. SNPs were analyzed with PCR-restriction fragment length polymorphism. Hidradenitis Suppurativa Clinical Response (HiSCR) score, International Hidradenitis Suppurativa Severity Scoring System 4 (IHS4) score, inflammatory lesion (AN) count, and draining tunnel (dT) count were collected at weeks 0, 12, 24, 36, and 48.

RESULTS

HiSCR response after 12 weeks of ADA treatment was 71.8% among carriers of the common GGG haplotype and 50.0% among carriers of minor frequency SNP haplotypes (p: 0.031; odds ratio: 0.39). This significant difference persisted until week 36. Carriers of minor frequency SNP haplotypes also had a lower relative decrease of the AN count at weeks 12 and 24; the dT count and IHS4 were not statistically different between the two groups.

CONCLUSIONS

Carriage of at least one minor frequency SNP haplotype of the promoter of the TNF gene is associated with a decreased response to ADA. This association may have an impact on treatment decision-making.

Genetic Influence on Treatment Response in Psoriasis: New Insights into Personalized Medicine

Psoriasis is a chronic inflammatory disease with an established genetic background. The HLA-Cw*06 allele and different polymorphisms in genes involved in inflammatory responses and keratinocyte proliferation have been associated with the development of the disease. Despite the effectiveness and safety of psoriasis treatment, a significant percentage of patients still do not achieve adequate disease control. Pharmacogenetic and pharmacogenomic studies on how genetic variations affect drug efficacy and toxicity could provide important clues in this respect. This comprehensive review assessed the available evidence for the role that those different genetic variations may play in the response to psoriasis treatment. One hundred fourteen articles were included in this qualitative synthesis. VDR gene polymorphisms may influence the response to topical vitamin D analogs and phototherapy. Variations affecting the ABC transporter seem to play a role in methotrexate and cyclosporine outcomes. Several single-nucleotide polymorphisms affecting different genes are involved with anti-TNF-α response modulation (TNF-α, TNFRSF1A, TNFRSF1B, TNFAIP3, FCGR2A, FCGR3A, IL-17F, IL-17R, and IL-23R, among others) with conflicting results. HLA-Cw*06 has been the most extensively studied allele, although it has only been robustly related to the response to ustekinumab. However, further research is needed to firmly establish the usefulness of these genetic biomarkers in clinical practice.

Impact of Functional Polymorphisms on Drug Survival of Biological Therapies in Patients with Moderate-to-Severe Psoriasis

Biological therapies (BTs) indicated for psoriasis are highly effective; however, not all patients obtain good results, and loss of effectiveness is the main reason for switching. Genetic factors may be involved. The objective of this study was to evaluate the influence of single-nucleotide polymorphisms (SNPs) on the drug survival of tumor necrosis factor inhibitors (anti-TNF) medications and ustekinumab (UTK) in patients diagnosed with moderate-to-severe psoriasis. We conducted an ambispective observational cohort study that included 379 lines of treatment with anti-TNF (n = 247) and UTK (132) in 206 white patients from southern Spain and Italy. The genotyping of the 29 functional SNPs was carried out using real-time polymerase chain reaction (PCR) with TaqMan probes. Drug survival was evaluated with Cox regression and Kaplan-Meier curves. The multivariate analysis showed that the HLA-C rs12191877-T (hazard ratio [HR] = 0.560; 95% CI = 0.40-0.78; p = 0.0006) and TNF-1031 (rs1799964-C) (HR = 0.707; 95% CI = 0.50-0.99; p = 0.048) polymorphisms are associated with anti-TNF drug survival, while TLR5 rs5744174-G (HR = 0.589; 95% CI = 0.37-0.92; p = 0.02), CD84 rs6427528-GG (HR = 0.557; 95% CI = 0.35-0.88; p = 0.013) and PDE3A rs11045392-T together with SLCO1C1 rs3794271-T (HR = 0.508; 95% CI = 0.32-0.79; p = 0.002) are related to UTK survival. The limitations are the sample size and the clustering of anti-TNF drugs; we used a homogeneous cohort of patients from 2 hospitals only. In conclusion, SNPs in the HLA-C, TNF, TLR5, CD84, PDE3A, and SLCO1C1 genes may be useful as biomarkers of drug survival of BTs indicated for psoriasis, making it possible to implement personalized medicine that will reduce financial healthcare costs, facilitate medical decision-making and improve patient quality of life. However, further pharmacogenetic studies need to be conducted to confirm these associations.

Pharmacogenomics on the Treatment Response in Patients with Psoriasis: An Updated Review

The efficacy and the safety of psoriasis medications have been proved in trials, but unideal responses and side effects are noted in clinical practice. Genetic predisposition is known to contribute to the pathogenesis of psoriasis. Hence, pharmacogenomics gives the hint of predictive treatment response individually. This review highlights the current pharmacogenetic and pharmacogenomic studies of medical therapy in psoriasis. HLA-Cw*06 status remains the most promising predictive treatment response in certain drugs. Numerous genetic variants (such as ABC transporter, DNMT3b, MTHFR, ANKLE1, IL-12B, IL-23R, MALT1, CDKAL1, IL17RA, IL1B, LY96, TLR2, etc.) are also found to be associated with treatment response for methotrexate, cyclosporin, acitretin, anti-TNF, anti-IL-12/23, anti-IL-17, anti-PDE4 agents, and topical therapy. Due to the high throughput sequencing technologies and the dramatic increase in sequencing cost, pharmacogenomic tests prior to treatment by whole exome sequencing or whole genome sequencing may be applied in clinical in the future. Further investigations are necessary to manifest potential genetic markers for psoriasis treatments.

Single nucleotide polymorphisms in ADAM17, IL23R and SLCO1C1 genes protect against infliximab failure in adults with Crohn's disease

BACKGROUND

To predict primary failure of infliximab (IFX) therapy in Crohn's disease (CD) and to identify patients who maintain long-term effectiveness to IFX is currently not feasible. Some genetic variations are proposed as potential biomarkers.

AIM

We assessed a set of single nucleotide polymorphisms (SNPs) in genes related to the IFX mechanism of action and the presence of HLA-DQA1 * 05 allele on the primary response and long-term durability in CD patients.

METHODS

A multi-centre cross-sectional study of IFX-exposed adult patients with CD was undertaken. Treatment persistence and time to failure were co-primary endpoints. DNA from the 131 patients was genotyped. Association between SNPs and clinical variables with IFX persistence was assessed.

RESULTS

Failure to IFX was documented in 65 (49.6%) out of 131 patients. IFX persistence was associated either with carrying the TT genotype in ADAM17 rs10929587 (ORa=0.2; 95%CI=0.1-0.8; p = 0.021), or the CC genotype in SLCO1C1 rs3794271 (ORa=0.2; 95%CI=0.1-0.7; p = 0.008), according to multivariate logistic regression. In contrast, previous bowel resection increased the risk of IFX failure (ORa=2.8; 95%CI=1.1-7.3; p = 0.025). Cox regression analysis confirmed these findings and also identified IL23R rs10489629-TT (HRa 0.41; 95%CI=0.22-0.75; p = 0.004) and concomitant immunosuppressants (HRa 0.46; 95%CI=0.27-0.77; p = 0.003) as protection from IFX failure. However, no association between HLA-DQA1 * 05 allele and persistence of IFX therapy was found, with similar failure rates among carriers and non-carriers (52.8% vs. 47.4%, respectively; p = 0.544).

CONCLUSIONS

SNPs rs10929587-TT in ADAM17, rs10489629-TT in IL23R and rs3794271-CC in SLCO1C1, together with no previous bowel surgery and concomitant immunosuppression, were identified as protection from failure to IFX.

Towards Personalized Medicine in Psoriasis: Current Progress

Although innovative targeted therapies have positively revolutionized psoriasis treatment shifting treatment goals to complete or almost complete skin clearance, primary or secondary lack of efficacy is still possible. Hence, identifying robust biomarkers that reflect the various clinical psoriasis phenotypes would allow stratify patients in subgroups or endotypes, and tailor treatments according to the characteristics of each individual (precision medicine). To sum up the current progress in personalized medicine for psoriasis, we performed a review on the available evidence on biomarkers predictive of response to psoriasis treatments, with focus on phototherapy and systemic agents. Relevant literature published in English was searched for using the following databases from the last five years up to March 20, 2022: PubMed, Embase, Google Scholar, EBSCO, MEDLINE, and the Cochrane library. Currently, more evidence exists towards biologicals, as justified by the huge health care costs as compared to phototherapy or conventional systemic drugs. Among them, most of the studies focused on anti-TNF and IL12/23, with still few on IL17 (mainly secukinumab). The most discussed biomarker gene is the HLA-C*02:06 status that has been shown to be associated with psoriasis, and also differential response to biologicals. Although its positivity is associated with great response to MTX, debatable results were retrieved concerning both anti-TNF and IL12/23 while it seems not to affect secukinumab response. Personalized treatment in psoriasis would provide excellent outcome minimizing the risk of side effects. To date, although several candidates were proposed and assessed, the scarcity and heterogeneity of the results do not allow the identification of the gold-standard biomarker per each treatment. Anyway, the creation of a more comprehensive panel would be more reliable for the treatment decision process.

Genome-wide association analysis of anti-TNF-α treatment response in Chinese patients with psoriasis

Background: TNF-α inhibitors are effective biological agents for treating psoriasis, but the treatment responses differ across patients. This study aimed to identify genetic biomarkers of anti-TNF-α response in Chinese psoriasis patients using a genome-wide association approach.

Methods: We recruited two independent cohorts of Chinese psoriasis patients administered etanercept biosimilar (with or without methotrexate). We identified 61 and 87 good responders (PASI improvement ≥75%), 19 and 10 poor responders (PASI improvement <50%) after 24 weeks treatment in the two cohorts, respectively. Then we performed genome-wide association studies (GWAS) on anti-TNF-α response in each cohort independently, followed by a fixed-effects inverse-variance meta-analysis in the 148 good and 29 poor responders.

Results: We tested genetic associations with >3 million genetic variants in either cohort. Meta-analysis identified significant associations within seven loci at p < 10⁻⁵, which also showed consistent association evidence in the two cohorts. These seven loci include rs2431355 (OR = 6.65, p = 4.46 × 10⁻⁷, IQGAP2-F2RL2 on 5q13.3), rs11801616 (OR = 0.11, p = 1.75 × 10⁻⁶, SDC3 on 1p35.2), rs3754679 (OR = 0.17, p = 7.71 × 10⁻⁶, CNOT11 on 2q11.2), rs13166823 (OR = 0.09, p = 3.71 × 10⁻⁶, IRF1-AS1 on 5q31.1), rs10220768 (OR = 5.49, p = 1.48 × 10⁻⁶, NPAP1 on 15q11.2), rs4796752 (OR = 5.56, p = 1.49 × 10⁻⁶, KRT31 on 17q21.2), and rs13045590 (OR = 0.08, p = 9.67 × 10⁻⁷, CTSZ on 20q13.3). Of the seven SNPs, six SNPs showed significant eQTL effect (p < 1 × 10⁻⁶) for several genes in multiple tissues.

Conclusion: These results suggest novel biological mechanisms and potential biomarkers for the response to anti-TNF therapies. These findings warrant further validation.

Psoriasis Patients with Specific HLA-Cw Alleles and Lower Plasma IL-17 Level Show Improved Response to Topical Lindioil Treatment

Purpose

Lindioil, a medicine refined from indigo naturalis (a herb used in Chinese medicine), is effective in treating severe psoriasis; however, responses vary across individual patients. We aim to investigate genetic predispositions associated with treatment response to topical Lindioil among patients with psoriasis and correlations with plasma cytokine patterns.

Patients and Methods

We enrolled 72 psoriasis patients treated with Lindioil ointment and analyzed the human leukocyte antigen class C (HLA-Cw) genotypes and plasma cytokine expression patterns. We developed regression models of treatment response, defined as Psoriasis Area and Severity Index (PASI) 75, to examine correlations among HLA-Cw alleles, cytokine levels, and treatment response to Lindioil.

Results

Patients harboring HLA-Cw*06:02 were significantly more likely to respond to Lindioil (P = 0.02, odds ratio [OR]: 6.88), whereas Lindoil was ineffective in those harboring HLA-Cw*01:02 (P = 0.01, OR: 0.28). Patients who were HLA-Cw*06:02-positive or HLA-Cw*01:02-negative had better PASI scores and body surface area (BSA) improvement (73.3% vs 44.4%, P<0.001) following an 8-week treatment period. Psoriasis patients achieving PASI 75 after 8 weeks presented with lower baseline plasma interleukin-17 (IL-17) levels than those who did not achieve PASI 75 (PASI 75: 11.28 pg/mL vs PASI <75: 15.82 pg/mL, P = 0.05).

Conclusion

Our findings suggest that the presence of the HLA-Cw*06:02 or HLA-Cw*01:02 alleles and plasma IL-17 levels are predictive markers of treatment response to Lindioil ointment in patients with psoriasis.

Clinical Application of Pharmacogenetic Markers in the Treatment of Dermatologic Pathologies

Dermatologic pathologies are the fourth most common cause of non-fatal disease worldwide; however, they produce a psychosocial, economic, and occupational impact equal to or greater than other chronic conditions. The most prevalent are actinic keratosis, followed by basal-cell carcinoma, in a lesser proportion acne vulgaris, psoriasis, and hidradenitis suppurativa, among others, and more rarely dermatitis herpetiformis. To treat actinic keratosis and basal-cell carcinoma, 5-fluorouracil (5-FU) 0.5% is administered topically with good results, although in certain patients it produces severe toxicity. On the other hand, dapsone is a drug commonly used in inflammatory skin conditions such as dermatitis herpetiformis; however, it occasionally causes hemolytic anemia. Additionally, biologic drugs indicated for the treatment of moderate-to-severe psoriasis and hidradenitis suppurativa have proved to be effective and safe; nevertheless, a small percentage of patients do not respond to treatment with biologics in the long term or they are ineffective. This interindividual variability in response may be due to alterations in genes that encode proteins involved in the pathologic environment of the disease or the mechanism of action of the medication. Pharmacogenetics studies the relationship between genetic variations and drug response, which is useful for the early identification of non-responsive patients and those with a higher risk of developing toxicity upon treatment. This review describes the pharmacogenetic recommendations with the strongest evidence at present for the treatments used in dermatology, highlighting those included in clinical practice guides. Currently, we could only find pharmacogenetic clinical guidelines for 5-FU. However, the summary of product characteristics for dapsone contains a pharmacogenetic recommendation from the United States Food and Drug Administration. Finally, there is an enormous amount of information from pharmacogenetic studies in patients with dermatologic pathologies (mainly psoriasis) treated with biologic therapies, but they need to be validated in order to be included in clinical practice guides.

TaaI/Cdx-2 AA Variant of VDR Defines the Response to Phototherapy amongst Patients with Psoriasis

1,25-dihydroxyvitamin-D₃ plays a central role in the immune system via binding to the vitamin D receptor. VDR polymorphisms have been associated with multiple autoimmune disorders, including psoriasis. Until now, five VDR polymorphisms, FokI, ApaI, BsmI, TaqI and TaaI/Cdx2, have been studied in psoriasis, with contradicting results. Therefore, this study aimed to evaluate the association of VDR polymorphisms with susceptibility to psoriasis, effectiveness of NB-UVB phototherapy and concentration of proinflammatory cytokines and vitamin D amongst the Polish population. VDR polymorphisms were analyzed by PCR-RFLP or real-time PCR. We found that the frequency of the TaaI/Cdx-2 GG genotype was significantly higher in psoriasis patients and was associated with regulation of IL-17 and IL-23 concentration. Moreover, TaaI/Cdx-2 AA might have a significant effect on the response to phototherapy amongst patients with psoriasis. Our results suggest that VDR is a susceptibility factor for psoriasis development. Moreover, TaaI/Cdx-2 variants have a significant effect on the response to phototherapy amongst patients with psoriasis and regulation of inflammatory response via decrease of IL-17 and IL-23 level after UVB phototherapy in the Polish population. Results of our study provide some evidence in support of the hypothesis that the vitamin D signaling pathway may be of relevance for pathogenesis and treatment of psoriasis.

Functional study of TNF-α promoter polymorphisms in psoriasis

BACKGROUND

TNF-α is an important mediator in the pathogenesis of psoriasis and polymorphisms influence its transcription and could be implicated in psoriasis risk and modify certain aspects of disease, such as age at onset of psoriasis vulgaris and disease severity. Six TNF-α single nucleotide polymorphisms (SNPs) in promoter region has been identified and studied but with discordant results. The aim of this study was to evaluate whether the polymorphisms in TNF-α (-238 (rs361525), -308 (rs1800629), -857 (rs1799724), -1031 (rs1799964)) are associated with gravity, prurity, early onset or response to drug therapy in psoriasis in Caucasian Italian patients.

METHODS

58 psoriasis patients from Turin PSOCARE, 23 with psoriasis vulgaris and 35 with psoriatic arthritis were studied. Ready to used master mix for allelic discrimination of rs1800629, rs361525 and rs1799964 respectively.

RESULTS

Our data showed a significant association between the -857(G) variant and both VAS-itch (p=0,03) and VAS-pain index (p=0,006), OR=0,2 (0,04-0,98) and OR=0,12 (0,02-0,59). No significant association between the genotypes or alleles of TNF-α SNPs as been observed with other clinic-pathologic parameters or etanercept response.

CONCLUSIONS

Our data suggest that -857 CC genotype could be involved in pain and itch severity in psoriasis patients.

Influence of Genetic Polymorphisms on Response to Biologics in Moderate-to-Severe Psoriasis

Psoriasis is a chronic inflammatory skin pathology of autoimmune origin and unknown etiology. There are various therapies for treating it, including a wide range of biopharmaceuticals indicated in moderate-to-severe psoriasis. Depending on their therapeutic target, they are classified as tumor necrosis factor inhibitors (anti-TNF) or cytokine inhibitors (interleukin-12, 23, and 17 antagonists). Although they have proved effective and safe, in clinical practice, many patients show a short- and long-term suboptimal response and even varying degrees of toxicity. This variability in response may be influenced by genetic factors, such as polymorphisms in the genes involved in the pathological environment, metabolism or mechanism of action of the drug that could affect the effectiveness and toxicity of biological therapies. This review assesses pharmacogenetic studies of the impact of genetic factors on response to biopharmaceuticals and toxicity in patients diagnosed with moderate-to-severe psoriasis. The results suggest that polymorphisms detected in the HLA genes, in genes that encode cytokines (TNF, IL genes, TNFAIP3), transporters (PDE3A-SLCO1C1, SLC12A8), receptors (TNFRSF1B, CD84, FCGR2A and FCGR3A, IL17RA, IL23R, TLR genes, PGLYRP4) and associated proteins (TNFAIP3, LY96, TIRAP, FBXL19), as well as other genes implicated in the pathogenesis of psoriasis (CDKAL1, CARD14, PTTG1, MAP3K1, ZNF816A, GBP6, CTNNA2, HTR2A, CTLA4, TAP1) can be used in the future as predictive markers of treatment response and/or toxicity with biological therapies in patients diagnosed with moderate-to-severe psoriasis, tailoring treatment to the individual patient.

Pharmacogenetics Update on Biologic Therapy in Psoriasis

Background and objectives: Psoriasis is a chronic immune-mediated skin disease caused by several complex factors, both environmental and genetic, many of which are still not fully understood. Nowadays, several groups of biological drugs are being used for psoriasis treatment. Although these therapies are very effective, they show significant variability in efficacy among individuals. Therefore, there is a need for biomarkers to predict treatment outcomes in order to guide personalized therapeutic decisions. Pharmacogenetics is the study of variations in DNA sequences related to drug response. Materials and Methods: In this article, we review pharmacogenetics studies on the treatment of moderate-to-severe psoriasis focusing on anti-interleukin (IL) 12/23 (ustekinumab) and anti-IL17 drugs (secukinumab and ixekizumab), as well as recent studies concerning anti-TNF drugs. Results: Several polymorphisms have been studied over the years in reference to anti-TNF drugs; some of the most recent studies included the performance of a genome-wide association study (GWAS) and pharmacogenetics studies focused on the optimization of a treatment regimen. Various polymorphisms in different genes have been related to ustekinumab response; among them, the most commonly studied is the HLA-C*06:02 allele. Conclusions: Although not confirmed in some studies, most studies have shown that patients carrying this allele present a significantly higher response rate to ustekinumab. Some polymorphisms have been studied in patients treated with anti-IL17 drugs, mostly related to secukinumab; however, up to now, no association has been found between any of these polymorphisms and response. Nevertheless, further studies involving larger cohorts are needed in order to confirm these results before the implementation of this biomarker in clinical practice.

Paradoxical Psoriasis Induced by Anti-TNFα Treatment: Evaluation of Disease-Specific Clinical and Genetic Markers

Paradoxical psoriasis (PP) may occur during treatment with anti-tumor necrosis factor-alpha (TNF-α) drugs in various chronic immune-mediated diseases, mainly inflammatory bowel diseases (IBD) and psoriasis. In this study, clinical and genetic characteristics of PP arising in IBD and psoriatic patients were investigated to identify disease-specific markers of the paradoxical effect. A total of 161 IBD and psoriatic patients treated with anti-TNF-α drugs were included in the study. Of these patients, 39 developed PP. All patients were characterized for the main clinical–pathologic characteristics and genotyped for six candidate single nucleotide polymorphisms (SNPs) selected for their possible role in PP susceptibility. In IBD patients, the onset of PP was associated with female sex, presence of comorbidities, and use of adalimumab. IBD patients with PP had a higher frequency of the TNF-α rs1799964 rare allele (p = 0.006) compared with cases without the paradoxical effect, and a lower frequency of the human leucocyte antigen (HLA)-Cw06 rs10484554 rare allele (p = 0.03) compared with psoriatic patients with PP. Overall, these findings point to specific clinical and genetic characteristics of IBD patients with PP and provide data showing that genetic variability may be related to the paradoxical effect of anti-TNF-α drugs with possible implications into clinical practice.

The HLA-Cw6 Dilemma: Is It Really an Outcome Predictor in Psoriasis Patients under Biologic Therapy? A Monocentric Retrospective Analysis

HLA-Cw6 is one of the most strongly associated psoriasis susceptibility alleles. Data regarding correlation between HLA-Cw6 status and biologic treatment outcomes are divergent. The aim of our study in our cohort of psoriatic patients was to explore if the HLA-Cw6 status influences the response rate to biologic therapies at 16 and 48 weeks. One hundred and one psoriatic patients eligible for biologic therapies were enrolled. HLA-C*06 alleles were detected from their blood samples. The effectiveness of antipsoriatic treatments was reported as 90% Psoriasis Area and Severity Index reduction (PASI90). All biologics showed efficacy at week 16, without significant differences between one another. HLA-Cw6 status did not seem to affect baseline characteristics, or treatment response at week 16. At week 48, IL-12/23 and IL-17 targeting drugs were more effective on Cw6-positive patients than on Cw6-negative patients. Conversely, TNF-targeting drugs seemed to be more effective on Cw6- negative patients than on Cw6-positive patients. The HLA-Cw6 test could well deserve to be integrated into the clinical laboratory work-up supporting the choice of the correct biologic.

Pharmacogenetics: A strategy for personalized medicine for autoimmune diseases

For many years, a considerable number of patients with autoimmune diseases (ADs) have suffered from a lack of drug response and drug-related toxicity. Despite the emergence of new therapeutic options such as biological agents, patients continue to struggle with these problems. Unfortunately, new challenges, including the paradoxical effects of biological drugs, have complicated the situation. In recent decades, efforts have been made to predict drug response as well as drug-related side effects. Thanks to the many advances in genetics, evaluation of markers to predict drug response/toxicity before the initiation of treatment may be an avenue toward personalizing treatments. Implementing pharmacogenetics and pharmacogenomics in the clinic could improve clinical care; however, obstacles remain to effective personalized medicine for ADs. The present study attempted to clarify the concept of pharmacogenetics/pharmacogenomics for ADs. After an overview on the pathogenesis of the most common types of treatments, this paper focuses on pharmacogenetic studies related to the selected ADs. Bridging the gap between pharmacogenetics and personalized medicine is also discussed. Moreover, the advantages, disadvantages and recommendations related to making personalized medicine practical for ADs have been addressed.

Knockdown of TRAF3IP2 suppresses the expression of VEGFA and the proliferation of keratinocytes and vascular endothelial cells

OBJECTIVE

To investigate the expression level of TRAF3IP2 in psoriasis lesion, and to explore the functional roles of TRAF3IP2 on proliferation, apoptosis, cytokine expression and secretion of both keratinocytes and vascular endothelial cells in vitro.

METHODS

The expression of TRAF3IP2 in skin samples of patients with psoriasis was analyzed by immunohistochemistry and qRT-PCR. To identify the effect of TRAF3IP2 knockdown on HaCaT and HUVEC cells, a plasmid vector expressing siRNA targeting TRAF3IP2 mRNA was designed and transfected into cells with Lipofectamine 2000. The levels of cytokines were identified using the ELISA Kits and qRT-PCR. Furthermore, cell proliferation, cell cycle and apoptosis were examined by using MTT, PI and Annexin V-FITC/7AAD assays, respectively. Furthermore, the expression of apoptosis-related proteins (Cleaved-Caspase 3, Caspase 3 and Bax) were detected by western blotting.

RESULTS

TRAF3IP2 was significantly upregulated in psoriasis lesion. TRAF3IP2 knockdown reduced the expression of vascular endothelial growth factor A (VEGFA) and the release of IL-6, and IL-8, but had no effect on IL-23 in both HaCaT and HUVEC cells. In addition, knockdown of TRAF3IP2 significantly inhibited cell proliferation through blocking the cell cycle in the G2/M phase. Moreover, knockdown of TRAF3IP2 increased the expression of Caspase 3, Cleaved-Caspase 3 and Bax, which was supported by the increased apoptosis of both HaCaT and HUVEC cells.

CONCLUSION

Taken together, these results indicated that TRAF3IP2 might play a contributive role in the pathogenesis of psoriasis and may serve as a new target for the treatment of psoriasis. VEGF related pathways may be involved in the mechanism beneath.

TT genotype of rs10036748 in TNIP1 shows better response to methotrexate in a Chinese population: a prospective cohort study

BACKGROUND

Methotrexate (MTX) is an efficacious treatment for psoriasis; however, its widespread application is limited by its unpredictable efficacy.

OBJECTIVES

To investigate the association of clinical factors and variants of psoriasis susceptibility genes with clinical responses to MTX in a prospective cohort.

METHODS

A total of 221 patients with psoriasis were recruited. Patients who achieved Psoriasis Area and Severity Index (PASI) improvement ≥ 75% at week 12 were defined as responders, whereas those with PASI improvement < 50% were defined as nonresponders. In 90 screening patients, genetic variants for 18 single-nucleotide polymorphisms in 14 susceptibility genes, and HLA-Cw6 status were initially compared for responders and nonresponders. Statistically significant associations in genetic variants were verified in all 221 patients.

RESULTS

Overall, 49% and 45% of patients achieved PASI 75 improvement during screening and verification stages, respectively. Concomitant arthritis with psoriasis and high body mass index (BMI) negatively affect the efficacy of MTX. TT genotype of rs10036748 in TNIP1 was significantly associated with PASI 75 response at week 12 (54% and 37%, P < 0·05). A significantly higher PASI 90 response was observed in patients with TT genotype of rs10036748 (27% vs. 12%, P < 0·01) and TC/TT genotype of rs4112788 in LCE3D (25% vs. 13%, P < 0·05) at week 12 compared with those who had other genotypes. After adjustment for all confounding factors, only BMI (P < 0·05), arthritis (P < 0·05) and genotype of rs10036748 (P < 0·05) were significantly associated with clinical responses to MTX.

CONCLUSIONS

Patients with psoriasis with TT genotype of rs10036748 in TNIP1, with lower BMI, without arthritis will achieve a better response to MTX.

Effect of Age of Onset of Psoriasis on Clinical Outcomes with Systemic Treatment in the Psoriasis Longitudinal Assessment and Registry (PSOLAR)

OBJECTIVE

Our objective was to compare therapeutic response among patients with early-onset psoriasis (EOP) and late-onset psoriasis (LOP) receiving adalimumab, etanercept, infliximab, ustekinumab, or methotrexate in the Psoriasis Longitudinal Assessment and Registry (PSOLAR).

METHODS

Patients were grouped by age of onset: EOP (age ≤ 40 years) or LOP (age > 40 years). Repeated-measures analysis with logistic regression was used to calculate the adjusted odds ratio (AOR; adjusted for baseline characteristics) for achieving a Physician's Global Assessment score of cleared/minimal (PGA 0/1) or a percentage of body surface area involved with psoriasis < 3% (%BSA < 3) or %BSA < 1 for all patients; similar sensitivity analyses were performed for each treatment group.

RESULTS

Of 7511 patients, 5479 (72.9%) had EOP. The LOP group had a higher likelihood of achieving PGA 0/1 after treatment than did the EOP group in all patients (AOR 1.14 [95% confidence interval (CI) 1.05-1.25]; p = 0.0019); the same was true in subgroups of etanercept-treated (AOR 1.38 [95% CI 1.14-1.66]; p = 0.0010) and methotrexate-treated (AOR 1.62 [95% CI 1.16-2.26]; p = 0.0049) patients. No significant difference was found between the EOP and LOP groups with regard to the likelihood of achieving %BSA < 3 or %BSA < 1 among all patients. However, LOP patients were more likely than EOP patients to achieve %BSA < 3 or %BSA < 1 in subgroups treated with infliximab (AOR 1.45 [95% CI 1.09-1.93; p = 0.0103] and AOR 1.36 [95% CI 1.03-1.78; p = 0.0290], respectively) and etanercept (AOR 1.30 [95% CI 1.06-1.61; p = 0.0123] and AOR 1.34 [95% CI 1.09-1.64; p = 0.0053], respectively).

CONCLUSION

Our real-world data from PSOLAR indicate that there are differences in some patient characteristics between EOP and LOP and that patients with EOP are less likely than those with LOP to respond to certain systemic treatments. (ClinicalTrials.gov identifier: NCT00508547).

Psoriasis in Skin of Color: Insights into the Epidemiology, Clinical Presentation, Genetics, Quality-of-Life Impact, and Treatment of Psoriasis in Non-White Racial/Ethnic Groups

Psoriasis is a chronic inflammatory skin condition affecting diverse racial/ethnic groups throughout the world. Large population-based studies suggest that psoriasis occurs most often in individuals of European ancestry, followed by black and Hispanic individuals, although the true prevalence of psoriasis in non-white individuals is likely underestimated. Despite similarities in psoriasis between ethnic groups, there are notable differences in the presentation, quality-of-life impact, and treatment of psoriasis with important implications for the management of non-white individuals. Overall, heterogeneity in psoriasis susceptibility alleles, in combination with cultural and socioeconomic factors, may explain these differences. In this article, we review the epidemiology, clinical presentation, genetic polymorphisms, quality-of-life impact, and treatment nuances of psoriasis in patients with skin of color.

Pharmacogenetics and Pharmacogenomics in Moderate-to-Severe Psoriasis

Pharmacogenetics is the study of variations in DNA sequence related to drug response. Moreover, the evolution of biotechnology and the sequencing of human DNA have allowed the creation of pharmacogenomics, a branch of genetics that analyzes human genes, the RNAs and proteins encoded by them, and the inter-and intra-individual variations in expression and function in relation to drug response. Pharmacogenetics and pharmacogenomics are being used to search for biomarkers that can predict response to systemic treatments, including those for moderate-to-severe psoriasis. Psoriasis is a chronic inflammatory disease with an autoimmune contribution. Although its etiology remains unknown, genetic, epigenetic, and environmental factors play a role in its development. Diverse systemic and biologic therapies are used to treat moderate-to-severe psoriasis. However, these treatments are not curative, and patients exhibit a wide range of responses to them. Moderate-to-severe psoriasis is usually treated with systemic immunomodulators such as acitretin, ciclosporin, and methotrexate. Anti-tumor necrosis factor (TNF) drugs (adalimumab, etanercept, or infliximab) are the first-line treatment for patients resistant to conventional systemic therapies. Although these therapies are very efficient, around 30-50% of patients have inadequate response. Ustekinumab is a monoclonal antibody that targets interleukin (IL)-12 and IL-23 and is used for moderate-to-severe psoriasis. New drugs (apremilast, brodalumab, guselkumab, ixekizumab, and secukinumab) have recently been approved for psoriasis. However, response rates to systemic treatments for moderate-to-severe psoriasis range from 35 to 80%, so it is necessary to identify non-invasive biomarkers that could help predict treatment outcomes of these therapies and individualize care for patients with psoriasis. These biomarkers could improve patient quality of life and reduce health costs and potential side effects. Pharmacogenetic studies have identified potential biomarkers for response to biologic treatments for moderate-to-severe psoriasis. These biomarkers need to be validated in clinical trials involving large cohorts of patients before they can be translated to the clinic. We review pharmacogenetics and pharmacogenomics studies for the treatment of moderate-to-severe plaque psoriasis.

HLA-Cw6 and psoriasis

Psoriasis is a multifactorial disease with a strong genetic background. HLA-Cw6 is one of the most strongly associated psoriasis susceptibility alleles. It is repeatedly observed to affect disease course, phenotypic features, severity, comorbidities and treatment outcomes. To the best of our knowledge, the roles of HLA-Cw6 in psoriasis have not yet been thoroughly reviewed. The worldwide frequency of the HLA-Cw6 allele varies greatly, with it being generally higher in white people than in Asians. The allele is associated with type I early-onset psoriasis. Stress, obesity and streptococcal pharyngitis are commonly observed in HLA-Cw6-positive patients. Phenotypically, HLA-Cw6 has been found to be associated with guttate psoriasis. In addition, patients carrying the allele are more likely to have arm, leg and trunk involvement, and the Koebner phenomenon. Patients with psoriatic arthritis with HLA-Cw6 more often have early onset and tend to show cutaneous symptoms before musculoskeletal symptoms. HLA-Cw6-positive patients have been shown in several studies to be more responsive to methotrexate and ustekinumab. However, this difference in ustekinumab efficacy was only moderate in a post-hoc analysis of a pivotal phase III study. HLA-Cw6 positivity also tends to be less frequent in high-need patients who fail conventional therapy. Small studies have also investigated the role of HLA-Cw6 in remission of psoriasis during pregnancy, and with the comorbidities of photosensitivity and atherosclerosis. Given the diverse nature of psoriasis pathogenesis, as well as the difference of HLA-Cw6 positivity in different ethnic groups, more studies are needed to confirm the role of HLA-Cw6 in psoriasis.

HLA-C*06:02 Does Not Predispose to Clinical Response Following Long-Term Adalimumab Treatment in Psoriatic Patients: A Retrospective Cohort Study

BACKGROUND

The genetic basis of predisposition to psoriasis is recognised; however, the response to psoriasis treatment in patients with different genetic predisposition is poorly understood.

OBJECTIVE

To analyse the presence of the HLA-C*06:02 polymorphism in psoriatic patients treated with adalimumab.

METHODS

Genomic DNA was extracted from whole blood of 122 patients with moderate-to-severe psoriasis treated with adalimumab for 3 years. Genotyping was performed using PCR. Disease severity was assessed by the Psoriasis Area and Severity Index (PASI) at day 0 and after 1, 3, 6, 12, 24 and 36 months. Logistic regression was used to evaluate the association between dependent variables (including HLA-C*06:02 status) and achievement of PASI 50, 75 and 90.

RESULTS

No difference was observed after adalimumab treatment between C*06:02 positive (HLA-C*06:02-POS) patients (n = 46) and C*06:02 negative (HLA-C*06:02-NEG) patients (n = 76) over the 3-year follow-up period in terms of PASI response or time-course when PASI response was achieved. However, a small, but non-statistically significant difference was noted between genotypes for PASI 50 at 1 month (HLA-C*06:02-NEG: 44.7% vs. HLA-C*06:02-POS: 56.5%) and at 3 months (HLA-C*06:02-NEG: 71.1% vs. HLA-C*06:02-POS: 80.4%). Simple logistic regression analysis did not reveal an association between independent variables (including C*06:02 status) and PASI response; however, multivariate regression revealed that gender (females better than males) was associated with achievement of PASI 50 at month 1 (OR 0.34, 95% CI 0.16-0.72, p = 0.005) and of PASI 75 at 3 months (OR 0.36, 95% CI 0.16-0.8, p = 0.012).

CONCLUSION

Adalimumab reduced long-term severity in patients with moderate-severe psoriasis, independent of their HLA-C*06:02 status.

Polymorphisms associated with adalimumab and infliximab response in moderate-to-severe plaque psoriasis

Aim: This study evaluated the influence of pharmacogenetics in psoriatic patients treated with adalimumab and/or infliximab. Materials & methods: Prospective observational study evaluating the association of 124 polymorphisms with the response to adalimumab or infliximab (PASI75) in patients with moderate-to-severe plaque psoriasis at 3 months (n = 95) and 6 months of treatment (n = 90). Significant SNPs for univariate analysis were subjected to multivariate analysis. Results: Five SNPs were associated with PASI75 at 3 months: rs6661932 (IVL), rs2546890 (IL-12B), rs2145623 (NFKBIA), rs9304742 (ZNF816A) and rs645544 (SLC9A8). Furthermore, rs1061624 (TNFR1B) was associated with PASI75 at 6 months. Conclusion: Nevertheless, these biomarkers should be validated in large-scale studies before implementation in clinical practice.

A systematic review of pharmacogenetic studies on the response to biologics in patients with psoriasis

BACKGROUND

Biologics are indicated for treating moderate-to-severe psoriasis. As the number of biologics registered for the treatment of psoriasis increases, so does the need for biomarkers to guide personalized therapeutic decisions. Genetic variants might serve as predictors for treatment response, a field of research known as pharmacogenetics.

OBJECTIVES

To assess which genetic variants are associated with response to biologics in patients with psoriasis according to current literature.

METHODS

A systematic search was performed in Embase, MEDLINE, the Cochrane Library and Web of Science. In total, 26 papers were included in this systematic review; 24 original studies and two meta-analyses. Quality was assessed using a predesigned form and risk of bias was assessed using the Newcastle-Ottawa Scale.

RESULTS

The majority of studies reported a candidate gene approach, focusing on polymorphisms in genes related to the therapeutic target or to psoriasis susceptibility. Studied populations were small and results were divergent, especially for studies investigating tumour necrosis factor inhibitors. The evidence for the role of HLA-Cw6 in ustekinumab efficacy shows minimal heterogeneity, with a higher response rate among patients who were positive for HLA-Cw6 reported across three of five studies.

CONCLUSIONS

Pharmacogenetic studies in psoriasis have generated divergent results. Replication of findings in larger cohorts is required. Large-scale hypothesis-free searches for genetic biomarkers are needed to uncover the complete genetic background of outcomes for treatment with biologics.

Polymorphisms associated with etanercept response in moderate-to-severe plaque psoriasis

AIM

Few studies have evaluated the influence of pharmacogenetics in psoriatic patients treated with etanercept.

MATERIALS & METHODS

We evaluated the association between 124 polymorphisms with the response to etanercept in patients with moderate-to-severe plaque psoriasis at 3 months (n = 78) and 6 months of treatment (n = 68).

RESULTS

The results of the multivariate analysis showed an association between polymorphisms rs13437088 (HLA-B/MICA), rs96844 (MAP3K1), rs2431697 (PTTG1), rs9304742 (ZNF816A) and the response to etanercept at 3 months. Besides polymorphisms rs928655 (GBP6) and rs2546890 (IL12B) were associated to response at 6 months.

CONCLUSIONS

Nevertheless, these biomarkers should be validated in large-scale studies before its implementation in clinical practice.

Classifying skin diseases: Until where should we go?

New molecular mapping techniques appear to allow clinicians to design treatments in some cases of resisting cancers. Such sensitive analysis were already able to depict molecular pathways of several inflammatory skin diseases. An accompanying article by Garzorz-Stark et al. show how these tools could improve the classification of skin inflammatory diseases now based on clinical and pathological features. At last, the final aim of these tools is to predict treatment response in a patient. The utility of "precision" or personalized medicine in cutaneous inflammatory diseases could join the furrow drawn in cancer.

Optimizing adalimumab treatment in psoriasis with concomitant methotrexate (OPTIMAP): study protocol for a pragmatic, single-blinded, investigator-initiated randomized controlled trial

BACKGROUND

The introduction of anti-tumor necrosis factor medications has revolutionized the treatment of psoriasis with achievement of treatment goals (Psoriasis Area and Severity Index score 75, remission) that are not usually met with conventional systemics. Nevertheless, some patients continue to experience persistent disease activity or treatment failure over time. Strategies to optimize treatment outcomes include the use of concomitant methotrexate, which has demonstrated beneficial effects on pharmacokinetics and treatment efficacy in psoriasis and other inflammatory diseases.

METHODS

This is an investigator-initiated, multicenter randomized controlled trial (RCT) designed to compare the combination treatment of adalimumab and methotrexate with adalimumab monotherapy in patients with psoriasis. The primary outcome is adalimumab drug survival at week 49. Other outcomes include improvement in disease severity and quality of life, tolerability, and safety. Moreover, anti-adalimumab antibodies and adalimumab serum concentrations will be measured and correlations between genotypes and clinical outcomes will be assessed. Patient recruitment started in March 2014. Up to now, 36 patients have been randomized. Many more patients have been (pre)screened. A total of 93 patients is desired to meet an adequate sample size. In our experience, the main limitation for recruitment is prior adalimumab therapy and intolerability or toxicity for methotrexate in the past.

DISCUSSION

OPTIMAP is the first RCT to examine combination therapy with adalimumab and methotrexate in a psoriasis population. With data derived from this study we expect to provide valuable clinical data on long-term treatment outcomes. These data will be supported by assessment of the impact of concomitant methotrexate on adalimumab pharmacokinetics. Furthermore, the influence of several single nucleotide polymorphisms on adalimumab response will be analyzed in order to support the development of a more personalized approach for this targeted therapy.

TRIAL REGISTRATION

NTR4499 . Registered on 7 April 2014.

Pharmacogenetics of ustekinumab in patients with moderate-to-severe plaque psoriasis

Aim/Materials & methods: Few studies have evaluated the influence of pharmacogenetics in psoriatic patients treated with ustekinumab. We evaluated 121 polymorphisms to study a possible association between these SNPs and the response to ustekinumab (PASI75 at 4 months; n = 69). Results/Conclusion: The adjusted results (false discovery rate) showed an association between five SNPs in TNFRSF1A, HTR2A, NFKBIA, ADAM33 and IL13 genes, and poor response to ustekinumab. Furthermore, six SNPs in CHUK, C17orf51, ZNF816A, STAT4, SLC22A4 and Corf72 genes were associated with better response to ustekinumab. However, there was no significant association between response to ustekinumab and SNPs in HLA-C as it has been recently described. Finally, a higher weight was obtained in nonresponders than responders (p = 0.018). Further studies would be necessary to be closer to personalized medicine.

Anti-TNF-α Drugs Differently Affect the TNFα-sTNFR System and Monocyte Subsets in Patients with Psoriasis

TNF-α has a central role in the development and maintenance of psoriatic plaques, and its serum levels correlate with disease activity. Anti-TNF-α drugs are, however, ineffective in a relevant percentage of patients for reasons that are currently unknown. To understand whether the response to anti-TNF-α drugs is influenced by the production of anti-drug antibodies or by the modulation of the TNFα-TNFα receptor system, and to identify changes in monocyte phenotype and activity, we analysed 119 psoriatic patients who either responded or did not respond to different anti-TNF-α therapies (adalimumab, etanercept or infliximab), and measured plasma levels of TNF-α, TNF-α soluble receptors, drug and anti-drug antibodies. Moreover, we analyzed the production of TNF-α and TNF-α soluble receptors by peripheral blood mononuclear cells (PBMCs), and characterized different monocyte populations. We found that: i) the drug levels varied between responders and non-responders; ii) anti-infliximab antibodies were present in 15% of infliximab-treated patients, while anti-etanercept or anti-adalimumab antibodies were never detected; iii) plasma TNF-α levels were higher in patients treated with etanercept compared to patients treated with adalimumab or infliximab; iv) PBMCs from patients responding to adalimumab and etanercept produced more TNF-α and sTNFRII in vitro than patients responding to infliximab; v) PBMCs from patients not responding to infliximab produce higher levels of TNF-α and sTNFRII than patients responding to infliximab; vi) anti- TNF-α drugs significantly altered monocyte subsets. A complex remodelling of the TNFα-TNFα receptor system thus takes place in patients treated with anti-TNF-α drugs, that involves either the production of anti-drug antibodies or the modulation of monocyte phenotype or inflammatory activity.

Psoriasis, psoriatic arthritis, and rheumatoid arthritis: Is all inflammation the same?

OBJECTIVES

To review the pathophysiology, co-morbidities, and therapeutic options for psoriasis, psoriatic arthritis and rheumatoid arthritis in order to further understand the similarities and differences in treatment paradigms in the management of each disease. New targets for individualized therapeutic decisions are also identified with the aim of improving therapeutic outcome and reducing toxicity.

SEARCH STRATEGY

Using the PubMed database, we searched literature published from 2000 to 2015 using combinations of the key words "psoriasis," "psoriatic arthritis," "rheumatoid arthritis," "pathogenesis," "immunomodulation," and "treatment."

INCLUSION AND EXCLUSION CRITERIA

This was a non-systematic review and there were no formal inclusion and exclusion criteria.

DATA EXTRACTION

Abstracts identified in the search were screened for relevance and articles considered appropriate evaluated further. References within these selected articles were also screened. Information was extracted from 198 articles for inclusion in this report.

DATA SYNTHESIS

There was no formal data synthesis. Articles were reviewed and summarized according to disease area (psoriasis, psoriatic arthritis, and rheumatoid arthritis).

HEADLINE RESULTS

The pathophysiology of psoriasis, psoriatic arthritis, and rheumatoid arthritis involves chronic inflammation mediated by pro-inflammatory cytokines. Dysfunction in integrated signaling pathways affecting different constituents of the immune system result in varying clinical features in the three diseases. Co-morbidities, including cardiovascular disease, malignancies, and non-alcoholic fatty liver disease are increased. Increased understanding of the immunopathogenesis allowed development of targeted treatments; however, despite a variety of potentially predictive genetic, protein and cellular biomarkers, there is still significant unmet need in these three inflammatory disorders.

TNF-α Promoter Polymorphisms Predict the Response to Etanercept More Powerfully than that to Infliximab/Adalimumab in Spondyloarthritis

While previous studies have researched in association analyses between TNFα promoter polymorphisms and responses to TNF blockers in spondyloarthritis patients, their results were conflicting. Therefore, we aimed to determine whether TNFα promoter polymorphisms could predict response to TNF blockers and find the source of heterogeneity. Data were extracted and analyzed from published articles and combined with our unpublished data. We found that the greatest potential sources of heterogeneity in the results were gender ratio, disease type, continents, and TNF blockers. Then Stratification analysis showed that the TNFα -308 G allele and the -238 G allele predicted a good response to TNF blockers (OR = 2.64 [1.48-4.73]; 2.52 [1.46-4.37]). However, G alleles of TNFα -308 and -238 could predict the response to etanercept (OR = 4.02 [2.24-7.23]; 5.17 [2.29-11.67]) much more powerfully than the response to infiliximab/adalimumab (OR = 1.68 [1.02-2.78]; 1.28 [0.57-2.86]). TNFα -857 could not predict the response in either subgroup. Cumulative meta-analysis performed in ankylosing spondylitis patients presented the odds ratio decreased with stricter response criteria. In conclusion, TNFα -308 A/G and -238 A/G are more powerful to predict the response to Etanercept and it is dependent on the criteria of response.