A new tool for early diagnosis of rheumatoid arthritis using combined biomarkers; synovial MAGE-1 mRNA and serum anti-CCP and RF

Clinical significance of long non-coding RNA NORAD in rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is a chronic autoimmune disease that may cause joint deformities and seriously affect the normal life of the patients. In order to enable patients to receive timely attention and treatment, this study developed new diagnostic markers by exploring the expression and molecular mechanism of the long non-coding RNA NORAD (NORAD) in RA.

METHODS

Participants including 77 RA patients and 52 healthy persons were enrolled, and the corresponding clinical data and serum samples were obtained. The NORAD and miR-204-5p expression were detected by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR). The content of inflammatory cytokines (IL-6, TNF-α) were determined through enzyme-linked immunosorbent assay (ELISA). Luciferase activity reporter assay demonstrated the association between NORAD and miR-204-5p. In addition, receiver operating characteristic (ROC) curve was used to evaluate the diagnostic efficacy of NORAD, and Pearson's correlation analysis was applied for the correlation analysis.

RESULTS

NORAD was enriched in RA serum with high diagnostic value. Simultaneously, IL-6 and TNF-α levels were also upregulated (P < 0.001). The C-reactive protein (CRP), rheumatoid factor (RF), erythrocyte sedimentation rate (ESR) and anti-cyclic citrullinated peptide antibody (Anti-CCP) levels in RA patients were generally elevated (P < 0.001). NORAD was positively correlated with the levels of clinical indicators and inflammatory factors (P < 0.0001). Mechanistically, NORAD may affect the progression of RA by targeting and negatively regulating miR-204-5p.

CONCLUSIONS

There is a correlation between NORAD and the processes of RA, and NORAD has the potential to predict and diagnose the occurrence of RA.

Biomarkers (mRNAs and non-coding RNAs) for the diagnosis and prognosis of rheumatoid arthritis

In recent years, diagnostic and therapeutic approaches for rheumatoid arthritis (RA) have continued to improve. However, in the advanced stages of the disease, patients are unable to achieve long-term clinical remission and often suffer from systemic multi-organ damage and severe complications. Patients with RA usually have no overt clinical manifestations in the early stages, and by the time a definitive diagnosis is made, the disease is already at an advanced stage. RA is diagnosed clinically and with laboratory tests, including the blood markers C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) and the autoantibodies rheumatoid factor (RF) and anticitrullinated protein antibodies (ACPA). However, the presence of RF and ACPA autoantibodies is associated with aggravated disease, joint damage, and increased mortality, and these autoantibodies have low specificity and sensitivity. The etiology of RA is unknown, with the pathogenesis involving multiple factors and clinical heterogeneity. The early diagnosis, subtype classification, and prognosis of RA remain challenging, and studies to develop minimally invasive or non-invasive biomarkers in the form of biofluid biopsies are becoming more common. Non-coding RNA (ncRNA) molecules are composed of long non-coding RNAs, small nucleolar RNAs, microRNAs, and circular RNAs, which play an essential role in disease onset and progression and can be used in the early diagnosis and prognosis of RA. In this review of the diagnostic and prognostic approaches to RA disease, we provide an overview of the current knowledge on the subject, focusing on recent advances in mRNA-ncRNA as diagnostic and prognostic biomarkers from the biofluid to the tissue level.

Value of combination of 25-(OH)-D3, IL-6, and cyclic peptide containing citrulline antibodies in different stages of rheumatoid arthritis

OBJECTIVE

To determine the value of a combination of 25-hydroxyvitamin D3 (25-(OH)-D3), interleukin-6 (IL-6), and cyclic peptide containing citrulline (CCP) antibodies in the acute stage and remission stage of patients with rheumatoid arthritis (RA).

METHODS

A retrospective analysis was made on 80 RA patients who received treatment in Wenjiang District People's Hospital of Chengdu from February 2017 to February 2020. According to their condition, they were identified as acute-stage patients (n=48) or remission-stage patients (n=32). In addition, 40 healthy individuals who received physical examination in our hospital during the same period were enrolled in a control group. Serum 25-(OH)-D3, IL-6, and CCP antibodies in all enrolled participants were quantified, and their levels were compared between RA patients at the acute stage and those at the remission stage before therapy, and also between patients with different efficacy after 3 months of therapy. The correlations of serum 25-(OH)-D3, IL-6, and CCP antibodies with disease activity score in 28 joints (DAS-28) were analyzed. A corresponding joint receiver operating characteristic (ROC) curve was drawn to analyze the diagnostic value of the combination of 25-(OH)-D3, IL-6, and CCP antibodies in the staging of RA patients, and logistic regression was used to establish an efficacy risk model.

RESULTS

The highest serum 25-(OH)-D3 level was found in the control group, followed by the remission-stage patients and then acute-stage patients from high to low (all P<0.05), and the lowest levels of serum IL-6 and CCP antibodies were also found in the control group, followed by the remission-stage patients and then the acute-stage patients from low to high (all P<0.05). The Pearson's test revealed a negative correlation of 25-(OH)-D3 with DAS-28 and a positive correlation of IL-6 and CCP antibodies with DAS-28. According to ROC curve-based analysis, the area under the joint curve of 25-(OH)-D3, IL-6, and CCP antibodies was >0.9. After therapy, patients showed an increase in 25-(OH)-D3 and decreases in IL-6 and CCP antibodies (all P<0.05). The logistic model confirmed that the area under the ROC curve of RA affecting the efficacy on patients was >0.8.

CONCLUSION

A combination of 25-(OH)-D3, IL-6, and CCP antibodies can be adopted as a diagnostic indicator in acute and remission stages of RA. A risk factor model of clinical efficacy in RA patients can help us effectively identify high-risk patients before therapy and take intervention measures early.