Polymorphism of genes involved in methotrexate pathway: Predictors of response to methotrexate therapy in Indian rheumatoid arthritis patients

A meta-analysis of the association between the ATIC 347 C/G polymorphism and methotrexate responsiveness and toxicity in rheumatoid arthritis

OBJECTIVES

The purpose of this study was to determine whether the 347 C/G polymorphism in the 5-aminoimidazole-4-carboxamide ribonucleotide transformylase (ATIC) gene predicts the responsiveness to or toxicity of methotrexate (MTX) in patients with rheumatoid arthritis (RA).

METHOD

To identify relevant publications, we searched the Medline, Embase, Cochrane, and Web of Science databases. We performed a meta-analysis of studies on the relationship between the ATIC 347 C/G polymorphism and MTX toxicity or non-responsiveness in patients with RA.

RESULTS

Thirteen studies consisting of 3,185 patients with RA satisfied our inclusion criteria. The analysis included 10 studies on MTX responsiveness and seven studies on MTX toxicity in patients with RA in connection with ATIC 347C/G polymorphism. According to our meta-analysis, the ATIC 347 GG genotype and failure to respond to MTX treatment were significantly associated (OR = 0.741, 95% CI = 0.591-0.929, p=0.009). According to stratification by ethnicity, this genotype was significantly associated with non-responsiveness to MTX in Europeans (OR=0.548, 95% CI=0.377-0.796, p=0.002) but not in Asian populations (OR=0.882, 95% CI=0.665-1.1172, p=0.388). However, analyses employing allelic, dominant, and homozygous contrast models failed to detect any relationship between the polymorphism and the failure to respond to MXT. However, the ATIC 347GG genotype and MTX toxicity were not associated (OR=1.278, 95% CI=0.937-1.745, p=0.121). Asian and European populations showed no evidence of a relationship between the ATIC 347GG genotype and MTX toxicity (OR=1.252, 95% CI=0.905-1.732, p=0.175 and OR =1.617, 95% CI=0.549-4.765, p=0.383, respectively).

CONCLUSIONS

This meta-analysis revealed that ATIC 347 C/G polymorphism was related to non-responsiveness to MTX in European populations with RA. However, no significant correlation was found with MTX toxicity.

Role of mitochondrial dysfunction in the pathogenesis of rheumatoid arthritis: Looking closely at fibroblast- like synoviocytes

Rheumatoid arthritis (RA) is a chronic, autoimmune, and inflammatory disease that primarily targets the joints, leading to cartilage and bone destruction.Fibroblast-like synoviocytes (FLS) are specialized cells of the synovial lining in the joint that plays a fundamental role in the development of RA. Particularly, FLS of RA patients (RA-FLS) in the joint exhibit specific characteristics like higher invading and immunogenic properties, hyperproliferation, and reduced apoptotic capacity, suggesting a dysfunctional mitochondrial pool in these cells. Mitochondria are emerging as a potential organelle that can decide cellular immunometabolism, invasion properties, and cell death. Accordingly, multiplestudies established that mitochondria are crucial in establishing RA. However, the underlying mechanism of impaired mitochondrial function in RA remains poorly understood. This review will provide an overview of the mitochondrial role in the progression of RA, specifically in the context of FLS biology. We will also outline how mitochondria-centric therapeutics can be achieved that would yield novel avenues of research in pathological mediation and prevention.

Case Report: Successful treatment with methotrexate in a 10-year-old boy with co-occurrence of generalized psoriasis and vitiligo

The co-occurrence of psoriasis (PsO) and vitiligo is rare in Asian countries, especially in children. This case report presents the first-ever occurrence of PsO combined with vitiligo in an Asian boy under 6 years of age, in whom symptom improvement was observed after the use of methotrexate (MTX) as the sole treatment. Although previous studies have indicated that there is a close correlation between the two diseases, methotrexate (MTX), which is a commonly used treatment for PsO, is not a standard treatment for vitiligo. Even with advanced progress in biologics and Janus kinase inhibitor (JAKi), the biologics and JAKi used in vitiligo are still inconsistent. In our case report, the successful use of MTX indicated that there are shared immune pathways between PsO and vitiligo. Further exploration is needed to optimize the treatment options for this co-occurrence of PsO and vitiligo.

Can Methotrexate Be Employed as Monotherapy for Bullous Pemphigoid? Analysis of Efficiency and Tolerance of Methotrexate Treatment in Patients with Bullous Pemphigoid

The European Academy of Dermatology and Venerology (EADV) consensus states that the treatment of choice for bullous pemphigoid is systemic glucocorticosteroid therapy. Bearing in mind that long-term steroid therapy is associated with numerous side effects, an effective and safer treatment regimen for these patients is still being sought. A retrospective analysis was performed of the medical reports of patients with diagnosed bullous pemphigoid. The study included 40 patients with moderate or severe disease, and who had continued ambulatory treatment for at least six months. The patients were divided into two groups: one treated with methotrexate in monotherapy, or with combined methotrexate and systemic steroid therapy. A slightly better survival rate was noted in the methotrexate group. No significant differences were observed between the groups in time to achieve clinical remission. The combination therapy group demonstrated more frequent disease recurrence and exacerbations during treatment, and a higher mortality rate. None of the patients in either group presented with severe side effects related to methotrexate treatment. The treatment of bullous pemphigoid with methotrexate in monotherapy is an effective and safe therapeutic method for elderly patients.