The potential role of RNA N6-methyladenosine in primary Sjögren's syndrome

Autoimmune disease: a view of epigenetics and therapeutic targeting

Autoimmune diseases comprise a large group of conditions characterized by a complex pathogenesis and significant heterogeneity in their clinical manifestations. Advances in sequencing technology have revealed that in addition to genetic susceptibility, various epigenetic mechanisms including DNA methylation and histone modification play critical roles in disease development. The emerging field of epigenetics has provided new perspectives on the pathogenesis and development of autoimmune diseases. Aberrant epigenetic modifications can be used as biomarkers for disease diagnosis and prognosis. Exploration of human epigenetic profiles revealed that patients with autoimmune diseases exhibit markedly altered DNA methylation profiles compared with healthy individuals. Targeted cutting-edge epigenetic therapies are emerging. For example, DNA methylation inhibitors can rectify methylation dysregulation and relieve patients. Histone deacetylase inhibitors such as vorinostat can affect chromatin accessibility and further regulate gene expression, and have been used in treating hematological malignancies. Epigenetic therapies have opened new avenues for the precise treatment of autoimmune diseases and offer new opportunities for improved therapeutic outcomes. Our review can aid in comprehensively elucidation of the mechanisms of autoimmune diseases and development of new targeted therapies that ultimately benefit patients with these conditions.

Clinical Characteristics of Distinct Subgroups of Patients with Primary Sjögren's Syndrome Classified by Serological Profiles: A Comparison Study

Sjögren's syndrome (SS) is an autoimmune disease characterized by heterogeneous clinical presentation and the presence of various autoantibodies. This study aimed to determine the differences in clinical findings according to antibody positivity in patients with primary Sjögren syndrome (pSS) in the Turkish population. A retrospective study was conducted and 402 patients (378 women and 24 men) with pSS were analyzed. The patients were categorized into three subgroups based on serological tests. These were (1) quadruple seropositivity (positive for anti-Sjögren's syndrome-related antigen A antibodies (anti-SSA; anti-Ro) and anti-Sjögren's syndrome-related antigen B antibodies (anti-SSB; anti-La), rheumatoid factor (RF), and antinuclear antibody (ANA); (2) double seropositivity (positive for ANA and anti-SSA/Ro antibodies); and (3) quadruple seronegativity (negative for ANA, RF, anti-SSA/Ro and anti-SSB/La antibodies). The number of quadruple-seropositive patients was 72 (18.6%), double-seropositive 174 (43.2%), and quadruple-seronegative was 85 (21.1%). The age at diagnosis of quadruple-seropositive pSS was 42.4 ± 10.8, which was significantly younger than that of patients with double-seropositive and quadruple-seronegative pSS (p = 0.021, p = 0.112). In terms of organ involvement, salivary gland enlargement, arthralgia, arthritis, Raynaud's phenomenon, lymphadenopathy, cutaneous vasculitis, interstitial lung disease, neurological involvement, autoimmune thyroiditis, renal interstitial disease, anemia, leukopenia, hypergammaglobulinemia, and hypocomplementemia were more common in quadruple-seropositive patients with pSS than in quadruple-seronegative patients (p < 0.0001). The results of this study confirmed the strong impact of immunological markers on the pSS phenotype at the time of diagnosis. Immunological patterns play a central role in the phenotypic expression of the disease, even during the initial diagnostic phase, and can guide physicians in designing personalized treatment plans for patients with pSS.

The Role of m6A Methylation in Tumor Immunity and Immune-Associated Disorder

N6-methyladenosine (m6A) represents the most prevalent and significant internal modification in mRNA, with its critical role in gene expression regulation and cell fate determination increasingly recognized in recent research. The immune system, essential for defense against infections and maintaining internal stability through interactions with other bodily systems, is significantly influenced by m6A modification. This modification acts as a key post-transcriptional regulator of immune responses, though its effects on different immune cells vary across diseases. This review delineates the impact of m6A modification across major system-related cancers-including those of the respiratory, digestive, endocrine, nervous, urinary reproductive, musculoskeletal system malignancies, as well as acute myeloid leukemia and autoimmune diseases. We explore the pathogenic roles of m6A RNA modifications within the tumor immune microenvironment and the broader immune system, highlighting how RNA modification regulators interact with immune pathways during disease progression. Furthermore, we discuss how the expression patterns of these regulators can influence disease susceptibility to immunotherapy, facilitating the development of diagnostic and prognostic models and pioneering new therapeutic approaches. Overall, this review emphasizes the challenges and prospective directions of m6A-related immune regulation in various systemic diseases throughout the body.

Identification of key genes with abnormal RNA methylation modification and selected m6A regulators in ankylosing spondylitis

BACKGROUND

N6-methyladenosine (m6A) has been identified as the most abundant modification of RNA molecules and the aberrant m6A modifications have been associated with the development of autoimmune diseases. However, the role of m6A modification in ankylosing spondylitis (AS) has not been adequately investigated. Therefore, we aimed to explore the significance of m6A regulator-mediated RNA methylation in AS.

METHODS

The methylated RNA immunoprecipitation sequencing (meRIP-seq) and digital RNA sequencing (Digital RNA-seq) were conducted using the peripheral blood mononuclear cells from three AS cases and three healthy controls, to identify genes affected by abnormal RNA methylation. The genes associated with different peaks were cross-referenced with AS-related genes obtained from the GeneCards Suite. Subsequently, the expression levels of shared differentially expressed genes (DEGs) and key m6A regulators in AS were evaluated using data from 68 AS cases and 36 healthy controls from two data sets (GSE25101 and GSE73754). In addition, the results were validated through quantitative polymerase chain reaction (qPCR).

RESULTS

The meRIP-seq and Digital RNA-seq analyses identified 28 genes with upregulated m6A peaks but with downregulated expression, and 52 genes with downregulated m6A peaks but with upregulated expression. By intersecting the genes associated with different peaks with 2184 AS-related genes from the GeneCards Suite, we identified a total of five shared DEGs: BCL11B, KAT6B, IL1R1, TRIB1, and ALDH2. Through analysis of the data sets and qPCR, we found that BCL11B and IL1R1 were differentially expressed in AS. Moreover, two key m6A regulators, WTAP and heterogeneous nuclear ribonucleoprotein C, were identified.

CONCLUSIONS

In conclusion, the current study revealed that m6A modification plays a crucial role in AS and might hence provide a new treatment strategy for AS disease.

Methylation of T and B Lymphocytes in Autoimmune Rheumatic Diseases

The role of abnormal epigenetic modifications, particularly DNA methylation, in the pathogenesis of autoimmune rheumatic diseases (ARDs) has garnered increasing attention. Lymphocyte dysfunction is a significant contributor to the pathogenesis of ARDs. Methylation is crucial for maintaining normal immune system function, and aberrant methylation can hinder lymphocyte differentiation, resulting in functional abnormalities that disrupt immune tolerance, leading to the excessive expression of inflammatory cytokines, thereby exacerbating the onset and progression of ARDs. Recent studies suggest that methylation-related factors have the potential to serve as biomarkers for monitoring the activity of ARDs. This review summarizes the current state of research on the impact of DNA and RNA methylation on the development, differentiation, and function of T and B cells and examines the progress of these epigenetic modifications in studies of six specific ARDs: systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, systemic sclerosis, juvenile idiopathic arthritis, and ankylosing spondylitis. Additionally, we propose that exploring the interplay between RNA methylation and DNA methylation may represent a novel direction for understanding the pathogenesis of ARDs and developing novel treatment strategies.

M6A methylation modification in autoimmune diseases, a promising treatment strategy based on epigenetics

BACKGROUND

N6-methyladenosine (m6A) methylation modification is involved in the regulation of various biological processes, including inflammation, antitumor, and antiviral immunity. However, the role of m6A modification in the pathogenesis of autoimmune diseases has been rarely reported.

METHODS

Based on a description of m6A modification and the corresponding research methods, this review systematically summarizes current insights into the mechanism of m6A methylation modification in autoimmune diseases, especially its contribution to rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE).

RESULTS

By regulating different biological processes, m6A methylation is involved in the pathogenesis of autoimmune diseases and provides a promising biomarker for the diagnosis and treatment of such diseases. Notably, m6A methylation modification is involved in regulating a variety of immune cells and mitochondrial energy metabolism. In addition, m6A methylation modification plays a role in the pathological processes of RA, and m6A methylation-related genes can be used as potential targets in RA therapy.

CONCLUSIONS

M6A methylation modification plays an important role in autoimmune pathological processes such as RA and SLE and represents a promising new target for clinical diagnosis and treatment, providing new ideas for the treatment of autoimmune diseases by targeting m6A modification-related pathways.

Roles of RNA Methylations in Cancer Progression, Autophagy, and Anticancer Drug Resistance

RNA methylations play critical roles in RNA processes, including RNA splicing, nuclear export, nonsense-mediated RNA decay, and translation. Regulators of RNA methylations have been shown to be differentially expressed between tumor tissues/cancer cells and adjacent tissues/normal cells. N6-methyladenosine (m6A) is the most prevalent internal modification of RNAs in eukaryotes. m6A regulators include m6A writers, m6A demethylases, and m6A binding proteins. Since m6A regulators play important roles in regulating the expression of oncogenes and tumor suppressor genes, targeting m6A regulators can be a strategy for developing anticancer drugs. Anticancer drugs targeting m6A regulators are in clinical trials. m6A regulator-targeting drugs could enhance the anticancer effects of current chemotherapy drugs. This review summarizes the roles of m6A regulators in cancer initiation and progression, autophagy, and anticancer drug resistance. The review also discusses the relationship between autophagy and anticancer drug resistance, the effect of high levels of m6A on autophagy and the potential values of m6A regulators as diagnostic markers and anticancer therapeutic targets.