A single nucleotide polymorphism of IL6-receptor is associated with response to tocilizumab in rheumatoid arthritis patients

Impact of IL6R genetic variants on treatment efficacy and toxicity response to sarilumab in rheumatoid arthritis

BACKGROUND

Sarilumab, an IL-6 receptor antagonist, is a first-line biologic disease-modifying anti-rheumatic drug for rheumatoid arthritis. The identification of genetic biomarkers as predictors of response to sarilumab could allow for a personalized treatment strategy to improve clinical outcomes.

METHODS

We conducted a retrospective cohort study of 62 patients treated with sarilumab to determine whether single-nucleotide polymorphisms (SNP) in the IL6R gene could predict efficacy and toxicity responses. Six SNPs previously described in the IL6R gene (rs12083537, rs11265618, rs4329505, rs2228145, rs4537545, and rs4845625) were genotyped in DNA samples obtained from these patients. Using parametric tests, we evaluated the association between these polymorphisms and clinicopathological features. Treatment response was assessed six months after treatment initiation. Satisfactory response was based on EULAR criteria. Low disease activity was determined according to DAS28 and CDAI and quantitative improvements in DAS28 and CDAI scores.

RESULTS

Three SNPs (rs4845625, rs4329505 and rs11265618) were significantly associated with response outcomes. All of the SNPs, except for rs12083537, had at least one significant association with dyslipidemia or hepatotoxicity.

CONCLUSIONS

These findings support the potential clinical value of SNPs, particularly rs4845625, as potentially useful biomarkers to predict response to sarilumab in patients with RA.

Clinical Value of IL6R Gene Variants as Predictive Biomarkers for Toxicity to Tocilizumab in Patients with Rheumatoid Arthritis

Tocilizumab is a first-line biologic disease-modifying anti-rheumatic drug (bDMARD) that inhibits the interleukin-6 (IL-6) pathway by antagonizing the IL-6 receptor (IL-6R). Tocilizumab is widely used to treat rheumatoid arthritis (RA), a prevalent autoimmune disease that can cause irreversible joint damage and disability. Although many bDMARDs have been developed for RA, there is a lack of validated biomarkers which could guide personalized medicine strategies. To evaluate whether single-nucleotide polymorphisms (SNPs) in the IL6R gene could predict tocilizumab toxicity in patients with RA, we conducted a retrospective cohort study of 88 patients treated with tocilizumab. Six SNPs previously described in the IL6R gene were genotyped (rs12083537, rs11265618, rs4329505, rs2228145, rs4537545, and rs4845625). Using parametric tests, we studied the association between the SNPs and hepatotoxicity, infection, hypersensitivity, gastrointestinal, hematological, and dyslipidemia adverse events (AEs). We found associations between dyslipidemia and rs4845625 and between hematological AEs and rs11265618 and rs4329505. No further associations were found for the remaining SNPs and other AEs. Our findings support the potential clinical value of SNPs in the IL6R gene as predictive biomarkers for toxicity to tocilizumab in patients with RA.

Role of IL6R Genetic Variants in Predicting Response to Tocilizumab in Patients with Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a prevalent autoimmune disease characterized by chronic arthritis that may lead to irreversible joint damage and significant disability. Patients with RA are commonly treated with Tocilizumab (TCZ), an IL-6 receptor (IL-6R) antagonist, but many patients refractorily respond to this therapy. Identifying genetic biomarkers as predictors of TCZ response could be a key to providing a personalized medicine strategy. We aimed to evaluate whether functional single nucleotide polymorphisms (SNPs) in the IL6R gene could predict TCZ response in patients with RA. We retrospectively included 88 RA patients treated with TCZ. Six SNPs previously described in the IL6R gene (rs12083537, rs11265618, rs4329505, rs2228145, rs4537545, and rs4845625) were genotyped in DNA samples from these patients. Using parametric tests, we evaluated the association between these polymorphisms and clinicopathological features. Responses to treatments were assessed at six months using three variables: a quantitative improvement in Disease activity score including 28 joints (DAS28), a satisfactory European League Against Rheumatism (EULAR) response, and low disease activity (LDA) achievement. The three response variables studied were associated with genetic variant rs4845625, and no association was found with the other five SNPs. Our findings support the potential clinical value of SNPs in the IL6R gene as predictive biomarkers for TCZ response.

Associations between the interleukin-6 rs1800795 G/C and interleukin-6 receptor rs12083537 A/G polymorphisms and response to disease-modifying antirheumatic drugs in rheumatoid arthritis: A meta-analysis

OBJECTIVE

We aimed to investigate the association between interleukin-6 (IL-6) rs1800795 G/C, IL-6 receptor (IL-6R) rs12083537 A/G, and rs4329505 T/C polymorphisms and responsiveness to disease-modifying antirheumatic drugs (DMARDs) in patients with rheumatoid arthritis (RA).

METHODS

We searched Medline, Embase, and Web of Science databases. We conducted a meta-analysis of studies on the association between the IL-6 rs1800795 G/C, IL-6R rs12083537 A/G and rs4329505 T/C polymorphisms and responsiveness to DMARDs in RA patients.

RESULTS

Fourteen studies from eight published articles involving 982 patients were included in this meta-analysis. The meta-analysis showed a significant association between the IL-6 rs1800795 G allele and response to DMARDs in RA (P = 0.008). Stratification by DMARD class showed that the IL-6 rs1800795 G allele was significantly associated with responsiveness to biological DMARDs (bDMARDs) (P = 0.022), but not conventional synthetic DMARDs (P = 0.145). A significant association was also found between the IL-6 rs1800795 G/C polymorphism and response to DMARDs. The meta-analysis revealed a significant association between the IL-6R rs12083537 A allele and response to tocilizumab in RA patients (P = 0.001). A significant association was also found between the IL-6R rs12083537 AA genotype and response to tocilizumab in RA patients (P = 0.001). However, no association was found between the IL-6R rs4329505 T/C polymorphism and response to tocilizumab.

CONCLUSIONS

This meta-analysis revealed associations between treatment response to bDMARDs and the IL-6 rs1800795 G/C polymorphism, and between response to tocilizumab and the IL-6R rs12083537 A/G polymorphism in RA.

Genetic Biomarkers as Predictors of Response to Tocilizumab in Rheumatoid Arthritis: A Systematic Review and Meta-Analysis

Rheumatoid arthritis (RA) is a lifelong, debilitating disease which incredibly impacts a patient’s quality of life if not treated to the optimal target. The clinical response of tocilizumab, an interleukin-6 (IL-6) inhibitor, is associated with several gene polymorphisms, particularly targeting the IL-6 pathway. This systematic review and meta-analysis seeks to investigate genetic biomarkers that predict the treatment outcome of tocilizumab therapy in RA patients. After evaluating the quality of retrieved records, five studies were chosen to carry out a quantitative synthesis involving 591 participants. We analysed genetic markers of IL-6R single nucleotide polymorphism (SNP)s rs12083537, rs2228145 and rs4329505, FCGR3A, CD69, GALNT18 and FCGR2A. A plausible finding based on meta-analysis revealed that RA patients with homozygous AA genotype for rs12083537 polymorphism of the IL-6R gene demonstrate a better response to TCZ treatment as opposed to homozygous and heterozygous patients with the G allele. Nonetheless, limitations in evaluating the available studies by meta-analysis include a lack of studies with dissimilarities in study design and outcome definitions, small sample sizes with low statistical power and heterogeneity of cohorts, a restricted the number of tested SNPs and small effects for the selected variants. Inconsistent finding remains as a great challenge to forge ahead towards personalised medicine for RA management.

Effects of the Interleukin-6 Receptor Blocker Sarilumab on Metabolic Activity and Differentiation Capacity of Primary Human Osteoblasts

Interleukin (IL-) 6 is a key factor in the inflammatory processes of rheumatoid arthritis. Several biologic agents target the IL-6 signaling pathway, including sarilumab, a monoclonal antibody that blocks the IL-6 receptor and inhibits IL-6-mediated cis- and trans-signaling. A careful analysis of the IL-6 signaling blockade should consider not only inflammatory processes but also the regenerative functions of IL-6. The purpose of this study was to investigate whether inhibition of the IL-6 receptors affects differentiation of human primary osteoblasts (hOB). The effects of sarilumab on viability and the differentiation capacity in unstimulated osteoblasts as well as after stimulation with various IL-6 and sIL6-R concentrations were determined. Sarilumab treatment alone did not affect the differentiation or induction of inflammatory processes in hOB. However, the significant induction of alkaline phosphatase activity which was observed after exogenous IL-6/sIL-6R costimulation at the highest concentrations was reduced back to baseline levels by the addition of sarilumab. The IL-6 receptor blockade also decreased gene expression of mediators required for osteogenesis and bone matrix maintenance. Our results demonstrate that concomitant administration of the IL-6 receptor blocker sarilumab can inhibit IL-6/sIL-6R-induced osteogenic differentiation.

Mechanisms underlying DMARD inefficacy in difficult-to-treat rheumatoid arthritis: a narrative review with systematic literature search

Management of RA patients has significantly improved over the past decades. However, a substantial proportion of patients is difficult-to-treat (D2T), remaining symptomatic after failing biological and/or targeted synthetic DMARDs. Multiple factors can contribute to D2T RA, including treatment non-adherence, comorbidities and co-existing mimicking diseases (e.g. fibromyalgia). Additionally, currently available biological and/or targeted synthetic DMARDs may be truly ineffective (‘true’ refractory RA) and/or lead to unacceptable side effects. In this narrative review based on a systematic literature search, an overview of underlying (immune) mechanisms is presented. Potential scenarios are discussed including the influence of different levels of gene expression and clinical characteristics. Although the exact underlying mechanisms remain largely unknown, the heterogeneity between individual patients supports the assumption that D2T RA is a syndrome involving different pathogenic mechanisms.

Toward Overcoming Treatment Failure in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disorder characterized by inflammation and bone erosion. The exact mechanism of RA is still unknown, but various immune cytokines, signaling pathways and effector cells are involved. Disease-modifying antirheumatic drugs (DMARDs) are commonly used in RA treatment and classified into different categories. Nevertheless, RA treatment is based on a "trial-and-error" approach, and a substantial proportion of patients show failed therapy for each DMARD. Over the past decades, great efforts have been made to overcome treatment failure, including identification of biomarkers, exploration of the reasons for loss of efficacy, development of sequential or combinational DMARDs strategies and approval of new DMARDs. Here, we summarize these efforts, which would provide valuable insights for accurate RA clinical medication. While gratifying, researchers realize that these efforts are still far from enough to recommend specific DMARDs for individual patients. Precision medicine is an emerging medical model that proposes a highly individualized and tailored approach for disease management. In this review, we also discuss the potential of precision medicine for overcoming RA treatment failure, with the introduction of various cutting-edge technologies and big data.

MicroRNA-106b Overexpression Suppresses Synovial Inflammation and Alleviates Synovial Damage in Patients with Rheumatoid Arthritis

OBJECTIVES

To explore the effect of miR-106b on synovial inflammation and damage in rheumatoid arthritis (RA) patients, and further to investigate its possible mechanism.

METHODS

: Quantitative real-time polymerase chain reaction (qRT-PCR), immunofluorescence, in situ hybridization and immunohistochemistry assay were separately used to verify the levels of miR-106b and cytokines in the synovial tissues of patients with RA or osteoarthritis (OA). Pearson correlation analysis was conducted to examine the bivariate relationship between miR-106b and cytokines or RANKL. Following the isolation and culture of fibroblast-like synoviocytes (FLS), the cells were transfected with lentivirus-mediated miR-106b mimic, miR-106b inhibitor, and negative control miR-106b mimic, respectively. Thereafter, cell proliferation was measured by Cell Counting Kit-8 assay, and cell invasion and migration capacity was assessed by Transwell assay. Furthermore, concentration and expression of cytokines were separately detected by Enzyme linked immunosorbent assay and Western blot.

RESULTS

Compared with osteoarthritis, validation by qRT-PCR showed that RA patients had a lower level of miR-106b and higher levels of receptor activator of nuclear factor-κ B ligand (RANKL), tumor necrosis factor-a (TNF-a) and interleukin-6 (IL-6). Additionally, the scatter plot showed that the relative transcription of miR-106b level was negatively correlated to the level of TNF-a, IL-6, and RNKAL in the synovial tissues of both RA and OA patients (All P<0.05). Furthermore, miR-106b overexpression suppressed cell proliferation, migration and invasion capacity of human RA-FLS.

CONCLUSIONS

miR-106b overexpression suppresses synovial inflammation and alleviates synovial damage, thus it may be served as a potential therapeutic target for RA patients.

Title Current Status of the Search for Biomarkers for Optimal Therapeutic Drug Selection for Patients with Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease characterized by destructive synovitis. It is significantly associated with disability, impaired quality of life, and premature mortality. Recently, the development of biological agents (including tumor necrosis factor-α and interleukin-6 receptor inhibitors) and Janus kinase inhibitors have advanced the treatment of RA; however, it is still difficult to predict which drug will be effective for each patient. To break away from the current therapeutic approaches that could be described as a “lottery,” there is an urgent need to establish biomarkers that stratify patients in terms of expected therapeutic responsiveness. This review deals with recent progress from multi-faceted analyses of the synovial tissue in RA, which is now bringing new insights into diverse features at both the cellular and molecular levels and their potential links with particular clinical phenotypes.

COVID-19 infection and rheumatoid arthritis: mutual outburst cytokines and remedies

In March 2020, COVID-19 infection caused by SARS-CoV-2 has been declared to be a global pandemic, where its complications, severity and mortality are reported to be due to the released inflammatory cytokines or the so-called cytokine storm. This is quite similar to that observed in the autoimmune and chronic inflammatory rheumatic disease, rheumatoid arthritis (RA). It was hypothesized that RA patients are at a higher risk of acquiring COVID-19; however, recent studies reported that they are not when compared to the rest of the population. In this review, we aim to highlight the mutual pathological features, cytokine profiles and risk factors between COVID-19 and RA. Also, many researchers are currently working to explore therapeutic agents that could aid in the eradication of COVID-19 infection. Due to the similarity between the inflammation status in COVID-19 and RA, many anti-rheumatic drugs such as hydroxychloroquine, tocilizumab, baricitinib and anakinra were proposed to be therapeutic modalities for COVID-19 infection.

NFKB1 promoter -94 insertion/deletion ATTG polymorphism (rs28362491) is associated with severity and disease progression of rheumatoid arthritis through interleukin-6 levels modulation in Egyptian patients

OBJECTIVE

Rheumatoid arthritis (RA) is an inflammatory autoimmune disorder, which can cause progressive and functional disability. Previous data suggests that some inflammatory cytokines are dysregulated in patients with RA. Polymorphisms in the NFKB1 gene were studied in different populations with RA. Specific studies showed that the NFKB1 promoter -94ins/delATTG (rs28362491) polymorphism appears to be correlated with alterations in the IL-6 expression and may lead to disease development. We aimed to evaluate the association between the NFKB1 -94ins/delATTG polymorphism and biochemical, and clinical markers for severity of RA in Egyptian patients.

METHODS

Study subjects included 196 RA patients from the Egyptian population. NFKB1 -94ins/delATTG polymorphism was genotyped by real-time PCR using the TaqMan assay. Concentrations of plasma IL-6 were assessed using the ELISA method.

RESULTS

The frequencies of (del/del + ins/del) genotype in cases with erosive arthritis were significantly increased as compared to cases with non-erosive arthritis (63.0% vs. 47.7%, OR = 1.86, 95% CI: 1.05-3.30, p: 0.043). Carriers of del allele had high activity and severity markers compared with those of ins/ins genotype. The del allele was significantly associated with higher IL-6 levels in a dose-dependent manner. Plasma levels of IL-6 were significantly higher in the del/del (41.4 ± 16.2 pg/ml) and ins/del (19.1 ± 12.4 pg/ml) genotype when compared with the ins/ins genotype (11.4 ± 4.21 pg/ml). In a multivariate analysis of variance, including confounding factors associated with higher IL-6 levels (RF, disease duration, and DAS28), the NFKB1 -94ins/delATTG polymorphism retained its role. Logistic regression analyses revealed that high IL-6 plasma levels independently associated with an increased risk of presenting erosive RA, while -94ins/delATTG polymorphism has no direct association with the progression of erosive arthritis.

CONCLUSION

Our data indicate that the NFKB1 -94ins/delATTG polymorphism contributes to the severity and progression of RA through IL-6 levels modulation in Egyptian patients. Key Points • Carriers of del allele had high activity and severity markers compared with those of ins/ins genotype. • In RA patients, the del allele was significantly associated with higher IL-6 levels in a dose-dependent manner. • IL-6 plasma levels are independently associated with an increased risk of presenting erosive arthritis. • The NFKB1 -94ins/delATTG polymorphism contributes to the severity and progression of RA through IL-6 levels modulation in Egyptian patients.

Rheumatology in the era of precision medicine: synovial tissue molecular patterns and treatment response in rheumatoid arthritis

PURPOSE OF REVIEW

A critical unmet need in rheumatoid arthritis (RA) is the identification of biomarkers that predict which of the available medications will be most effective for an individual in order to lower disease activity sooner than is afforded by the current treat-to-target approach. Here we will discuss recent reports examining the potential for synovial tissue molecular, cellular, and spatial profiling in defining objective measures of treatment response and therein developing personalized medicine for RA.

RECENT FINDINGS

Recent high-dimensional molecular profiling of RA synovium has provided unprecedented resolution of the cell types and pathways in tissues affected by rheumatic diseases. Heightened attention to tissue architecture is also emerging as a means to classify individual disease variation that may allow patients to be further stratified by therapeutic response. Although this wealth of data may have already pinpointed promising biomarkers, additional studies, likely including tissue-based functional drug response assays, will be required to demonstrate how the complex tissue environment responds.

SUMMARY

Molecular, cellular, and more recently spatial profiling of the RA synovium are uncovering fundamental features of the disease. Current investigations are examining whether this information will provide meaningful biomarkers for individualized medicine in RA.

Polymorphisms Involved in Response to Biological Agents Used in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a systemic disease that leads to joint destruction. During the last decade, the therapy of RA has been principally based on biological drugs. Although the efficacy of biological therapy has been established, patients demonstrated a high heterogeneity in clinical response to treatment. Several genetic polymorphisms play a part in the different response to biological drugs. This review summarizes the pharmacogenetics of biological agents approved for clinical RA treatment. We reviewed PubMed papers published over the past 20 years (2000-2020), inserting as the search term "rheumatoid arthritis and polymorphisms". Despite some studies showing important correlations between genetic polymorphisms and response to biological therapy in RA patients, most of these findings are still lacking and inconsistent. The personalized treatment according to a pharmacogenetics approach is promising but the available pharmacogenetics data on biological treatment in RA are not adequate and reliable to recommend pharmacogenetic tests before starting biological therapy in RA patients.

SARS-CoV-2: An immunogenetics call to arms

Susceptibility to viral infection, development of immunity, response to treatment and patient clinical outcomes are all under the control of heritable factors in the host. In the context of the current SARS-Cov-2 pandemic, this review considers existing immunogenetic knowledge of virus-immune system interactions. A major focus is to highlight areas in which work is required in order to improve understanding of antiviral immune responses and to move towards improved patient management.

Genetic Polymorphisms Associated with Rheumatoid Arthritis Development and Antirheumatic Therapy Response

Rheumatoid arthritis (RA) is the most common inflammatory arthropathy worldwide. Possible manifestations of RA can be represented by a wide variability of symptoms, clinical forms, and course options. This multifactorial disease is triggered by a genetic predisposition and environmental factors. Both clinical and genealogical studies have demonstrated disease case accumulation in families. Revealing the impact of candidate gene missense variants on the disease course elucidates understanding of RA molecular pathogenesis. A multivariate genomewide association study (GWAS) based analysis identified the genes and signalling pathways involved in the pathogenesis of the disease. However, these identified RA candidate gene variants only explain 30% of familial disease cases. The genetic causes for a significant proportion of familial RA have not been determined until now. Therefore, it is important to identify RA risk groups in different populations, as well as the possible prognostic value of some genetic variants for disease development, progression, and treatment. Our review has two purposes. First, to summarise the data on RA candidate genes and the increased disease risk associated with these alleles in various populations. Second, to describe how the genetic variants can be used in the selection of drugs for the treatment of RA.

Joint Reconstituted Signaling of the IL-6 Receptor via Extracellular Vesicles

Interleukin-6 (IL-6) signaling is a crucial regulatory event important for many biological functions, such as inflammation and tissue regeneration. Accordingly, several pathological conditions are associated with dysregulated IL-6 activity, making it an attractive therapeutic target. For instance, blockade of IL-6 or its α-receptor (IL-6R) by monoclonal antibodies has been successfully used to treat rheumatoid arthritis. However, based on different signaling modes, IL-6 function varies between pro- and anti-inflammatory activity, which is critical for therapeutic intervention. So far, three modes of IL-6 signaling have been described, the classic anti-inflammatory signaling, as well as pro-inflammatory trans-signaling, and trans-presentation. The IL-6/IL-6R complex requires an additional β-receptor (gp130), which is expressed on almost all cells of the human body, to induce STAT3 (signal transducer and activator of signal transcription 3) phosphorylation and subsequent transcriptional regulation. In contrast, the IL-6R is expressed on a limited number of cells, including hepatocytes and immune cells. However, the proteolytic release of the IL-6R enables trans-signaling on cells expressing gp130 only. Here, we demonstrate a fourth possibility of IL-6 signaling that we termed joint reconstituted signaling (JRS). We show that IL-6R on extracellular vesicles (EVs) can also be transported to and fused with other cells that lack the IL-6R on their surface. Importantly, JRS via EVs induces delayed STAT3 phosphorylation compared to the well-established trans-signaling mode. EVs isolated from human serum were already shown to carry the IL-6R, and thus this new signaling mode should be considered with regard to signal intervention.