Gene expression analysis of vascular pathophysiology related to anti-TNF treatment in rheumatoid arthritis

Does Adding Single-Nucleotide Polymorphisms to Risk Algorithms Improve Cardiovascular Disease Risk Prediction in Rheumatoid Arthritis? An Internal and External Validation of a Clinical Risk Score

OBJECTIVE

Current risk algorithms do not accurately predict cardiovascular disease (CVD) risk in rheumatoid arthritis (RA). An area of interest is that of single-nucleotide polymorphisms (SNPs), of which several have been associated with CVD in the general population. We investigated whether these SNPs are associated with CVD in RA and whether SNPs could improve CVD risk prediction in RA.

METHODS

Sixty SNPs were genotyped in 353 patients with RA. Logistic and Cox regression analyses were performed to identify SNPs that were associated with CVD (n = 99). A prediction model with clinical variables was made. SNPs were added to investigate the additional predictive value. Both models were internally validated. External validation was done in a separate cohort (n = 297).

RESULTS

rs3184504, rs4773144, rs12190287, and rs445925 were significantly associated with new CVD. The clinical prediction model consisted of age, sex, body mass index, systolic blood pressure, high-density lipoprotein cholesterol (HDLc), and creatinine, with an area under the curve (AUC) of 0.74 (P = 0.03). Internal validation resulted in an AUC of 0.76 (P < 0.01). A new model was made including SNPs and resulted in a model with rs17011666 and rs801426, age, total cholesterol, and HDLc, which performed slightly better with an AUC of 0.77 (P < 0.01). External validation resulted in a good fit for the clinical model, but a poor fit for the SNP model.

CONCLUSION

Several SNPs were associated with CVD in RA. Risk prediction slightly improved after adding SNPs to the models, but the clinical relevance is debatable. However, larger studies are needed to determine more accurately the additional value of these SNPs to CVD risk prediction algorithms.

Gene Ontology Analysis Highlights Biological Processes Influencing Non-Response to Anti-TNF Therapy in Rheumatoid Arthritis

Anti-TNF therapy has significantly improved disease control in rheumatoid arthritis, but a fraction of rheumatoid arthritis patients do not respond to anti-TNF therapy or lose response over time. Moreover, the mechanisms underlying non-response to anti-TNF therapy remain largely unknown. To date, many single biomarkers of response to anti-TNF therapy have been published but they have not yet been analyzed as a system of interacting nodes. The aim of our study is to systematically elucidate the biological processes underlying non-response to anti-TNF therapy in rheumatoid arthritis using the gene ontologies of previously published predictive biomarkers. Gene networks were constructed based on published biomarkers and then enriched gene ontology terms were elucidated in subgroups using gene ontology software tools. Our results highlight the novel role of proteasome-mediated protein catabolic processes (p = 2.91 × 10⁻¹⁵) and plasma lipoproteins (p = 4.55 × 10⁻¹¹) in anti-TNF therapy response. The results of our gene ontology analysis help elucidate the biological processes underlying non-response to anti-TNF therapy in rheumatoid arthritis and encourage further study of the highlighted processes.

Pharmacogenomics of Anti-TNF Treatment Response Marks a New Era of Tailored Rheumatoid Arthritis Therapy

Rheumatoid arthritis (RA) is the most commonly occurring chronic inflammatory arthritis, the exact mechanism of which is not fully understood. Tumor Necrosis Factor (TNF)-targeting drugs has been shown to exert high effectiveness for RA, which indicates the key importance of this cytokine in this disease. Nevertheless, the response to TNF inhibitors varies, and approximately one third of RA patients are non-responders, which is explained by the influence of genetic factors. Knowledge in the field of pharmacogenomics of anti-TNF drugs is growing, but has not been applied in the clinical practice so far. Different genome-wide association studies identified a few single nucleotide polymorphisms associated with anti-TNF treatment response, which largely map genes involved in T cell function. Studies of the gene expression profile of RA patients have also indicated specific gene signatures that may be useful to develop novel prognostic tools. In this article, we discuss the significance of TNF in RA and present the current knowledge in pharmacogenomics related to anti-TNF treatment response.

Declining levels of serum chemokine (C-X-C motif) ligand 10 over time are associated with new onset of psoriatic arthritis in patients with psoriasis: a new biomarker?

BACKGROUND

We previously found that serum levels of chemokine (C-X-C motif) ligand 10 (CXCL10) decreased after the onset of psoriatic arthritis (PsA).

OBJECTIVES

We measured CXCL10 levels over time in patients with psoriasis who developed PsA to determine whether the drop in CXCL10 was specific to these patients and further assess its association with PsA development.

METHODS

Prospectively followed patients with psoriasis without arthritis [cutaneous psoriasis (PsC)] were assessed yearly by rheumatologists for the presence of PsA. Patients with PsC who developed PsA (converters) were matched to those that did not develop PsA (nonconverters) based on psoriasis duration and the interval between follow-up visits. The duration between baseline and the first visit postconversion in converters was used to assign a pseudoconversion date in nonconverters. Linear mixed-effects models were used to model the expression of CXCL10 over time.

RESULTS

CXCL10 significantly declined over time in converters prior to PsA development with a significant difference in the trend over time between converters (n = 29) and nonconverters (n = 52; P < 0·001). CXCL10 continued to decline after PsA onset in a subset of converters. There was a significant difference in the trend of CXCL10 levels between converters (n = 24) and nonconverters (n = 16; P = 0·01) preconversion/pseudoconversion. This difference remained postconversion (P = 0·006) and was not different from the preconversion period (P = 0·75).

CONCLUSIONS

A large difference in CXCL10 was identified in patients with PsC that are destined to develop PsA over time. This exploratory analysis supports the association of CXCL10 with PsA development in patients with PsC and warrants further study of the predictive ability of this chemokine. What is already known about this topic? Chemokine (C-X-C motif) ligand 10 (CXCL10) is elevated in psoriatic affected tissues and serum and/or plasma. Patients with psoriasis that develop psoriatic arthritis (PsA) have elevated CXCL10 levels at baseline and these levels drop after arthritis onset. What does this study add? By monitoring levels of CXCL10 in serum over multiple visits in patients with psoriasis that develop PsA as well as those that do not develop PsA, an association was identified between CXCL10 and PsA development. What is the translational message? CXCL10 is a strong candidate for use by physicians for the detection of patients with psoriasis that are at risk of developing PsA. Linked Comment: Kirby and Fitzgerald. Br J Dermatol 2020; 183:805-806.

mRNA level of ROCK1, RHOA, and LIMK2 as genes associated with apoptosis in evaluation of effectiveness of adalimumab treatment

BACKGROUND

Psoriasis is a multifactorial autoimmune disease, which underlies the abnormalities of the apoptotic process. In cases of psoriasis and psoriatic arthritis, biological treatment is used. This study aimed to determine any changes in the expression of the genes associated with apoptosis in patients with psoriatic arthritis treated with adalimumab and to assess any phenotypic modifications based on changes in dermatological indexes.

METHODS

The study included 20 patients with psoriatic arthritis treated biologically and 20 healthy volunteers. The research material consisted of peripheral blood mononuclear cells (PBMCs) from which the total RNA was isolated. Changes in the gene expression were determined using oligonucleotide microarrays and RT-qPCR. The clinical condition was assessed based on selected indicators: PASI, BSA [%], DAS28, and DLQI, which were determined every 3 months.

RESULTS

There were changes in the expression of genes associated with apoptosis. Significant differences were found for ROCK1, RhoA, and LIMK2 expression profiles in PBMCs. At the initial stage of treatment, a decrease in the PASI and BSA rates was observed. At the later stages, the values of these indicators increased once again. There were correlations between the changes in these genes' expression and the dermatological markers.

CONCLUSION

Adalimumab influences the expression of genes related to apoptosis and the values of dermatological indicators of patients. Changes in the expression level of genes associated with apoptosis suggest that ROCK1, RhoA, and LIMK2 may be genes that can potentially be indicators of treatment effectiveness and lack of response to biological treatment.

Adalimumab changes the expression profile of selected BCL-2 family genes

Biological drugs are an alternative to treatment of psoriasis and psoriatic arthritis. Adalimumab is a representative of the anti-TNF group. The underlying of this disease is a cellular homeostasis disorder-apoptosis. Many proteins are involved in the apoptosis induction pathways, including those from the BCL-2 family. The aim of the study was to perform a transcriptional analysis of the genes coding selected proteins from the BCL-2 family in patients treated with adalimumab therapy, and to determine the direction of these changes. The test materials were peripheral blood mononuclear cells. The cells were obtained from 20 patients with psoriatic arthritis who were being treated with adalimumab (study group) and 20 healthy volunteers (control). The gene expression profile was determined using the real-time quantitative reverse transcription polymerase chain reaction technique. Statistically significant changes were observed in the expression level of the BNIP3, BNIP3L, and BCL2L1 genes (p < .05) during a 24-month observation of therapy. We indicated that adalimumab therapy has an impact on the expression of the analyzed genes, which may constitute a new class of molecular markers for assessing the effectiveness of a therapy. It appears that the BNIP3L gene could be used as a potential diagnostic marker of psoriasis.

Effects of 1-year anti-TNF-α therapy on vascular function in rheumatoid arthritis and ankylosing spondylitis

Accelerated atherosclerosis, increased cardiovascular morbidity and mortality have been associated with rheumatoid arthritis (RA) and ankylosing spondylitis (AS). Vascular function, clinical and laboratory markers and the effects of anti-TNF therapy were assessed in arthritides. Fifty-three 53 patients including 36 RA patients treated with either etanercept (ETN) or certolizumab pegol and 17 AS patients treated with ETN were included in a 12-month follow-up study. Ultrasonography was performed to determine flow-mediated vasodilation (FMD), common carotid intima-media thickness (ccIMT) and arterial pulse-wave velocity (PWV) in all patients. All assessments were performed at baseline and 6 and 12 months after treatment initiation. A significant improvement of brachial artery FMD was observed after 6 months (p = 0.004). A tendency of FMD improvement was also observed after 12 months (p = 0.065). ccIMT did not change throughout the year. PWV significantly improved after 12 months (p = 0.034). Higher baseline ccIMT (p = 0.009) and PWV (p = 0.038) were associated with clinical non-response (cNR) versus response (cR) to biologics. Multiple analysis confirmed the association of baseline ccIMT with age (p = 0.003) and cNR (p = 0.009), as well as that of baseline PWV with age at diagnosis (p = 0.022) and current chest pain (p = 0.004). Treatment itself determined the 12-month changes in FMD (p = 0.020) and PWV (p = 0.007). In a mixed cohort of RA and AS patients, TNF inhibition improved or stabilized vascular pathophysiology. Inflammation may be associated with FMD, while, among others, cNR may influence vascular function.

Subclinical and clinical atherosclerosis in rheumatoid arthritis: results from the 3-year, multicentre, prospective, observational GIRRCS (Gruppo Italiano di Ricerca in Reumatologia Clinica e Sperimentale) study

Background

Rheumatoid arthritis (RA) is associated with an increased risk of morbidity and mortality, when compared with general population, largely due to enhanced atherosclerotic disease. In this work, we aimed at assessing both occurrence and predictive factors of subclinical and clinical atherosclerosis in RA.

Methods

From January 1, 2015, to December 31, 2015, consecutive participants with RA, admitted to Italian Rheumatology Units, were assessed in the GIRRCS (Gruppo Italiano di Ricerca in Reumatologia Clinica e Sperimentale) cohort. After that, those participants were followed up in a 3-year, prospective, observational study, assessing the occurrence of subclinical and clinical atherosclerosis and possible predictive factors. McNemar test was employed to assess the changes in subclinical and clinical atherosclerosis, and regression analyses exploited the ORs for the occurrence of those comorbidities.

Results

We analysed 841 participants, mostly female (82.2%) and with median age of 60 years (range 21–90). The remission was achieved and maintained by 41.8% of participants during the follow-up. We observed an increased rate of subclinical atherosclerosis at the end of follow-up (139 vs 203 participants, p < 0.0001), particularly in participants with a disease duration less than 5 years at baseline (70 participants vs 133 participants, p < 0.0001). Type 2 diabetes (T2D) (OR 4.50, 95%CI 1.74–11.62, p = 0.002), high blood pressure (OR 2.03, 95%CI 1.04–4.14, p = 0.042), ACPA (OR 2.36, 95%CI 1.19–4.69, p = 0.014) and mean values of CRP during the follow-up (OR 1.07, 95%CI 1.03–1.14, p = 0.040) were significantly associated with higher risk of subclinical atherosclerosis. We observed an increased rate of clinical atherosclerosis at the end of follow-up (48 vs 76 participants, p < 0.0001). T2D (OR 6.21, 95%CI 2.19–17.71, p = 0.001) was associated with a significant risk of clinical atherosclerosis. The achievement and the maintenance of remission reduced the risk of subclinical (OR 0.25, 95%CI 0.11–0.56, p = 0.001) and clinical atherosclerosis (OR 0.20, 95%CI 0.09–0.95, p = 0.041).

Conclusions

We reported an increased prevalence and incidence of both subclinical and clinical atherosclerosis in 3-year prospectively followed participants, mainly in the subset with a duration of disease less than 5 years. The achievement and the maintenance of remission are associated with a reduction of the risk of subclinical and clinical atherosclerosis. Among “traditional” cardiovascular risk factors, participants with T2D showed a higher risk of clinical and subclinical atherosclerosis.

Electronic supplementary material

The online version of this article (10.1186/s13075-019-1975-y) contains supplementary material, which is available to authorized users.