Circular RNAs (circRNAs) are a type of endogenous non-coding RNA that were discovered to regulate gene expression through multiple pathways. Metastasis remains one of the biggest obstacles in cancer treatment. In this review, we focus on circRNAs involved in cancer tumorigenesis and metastasis. We present recently identified tumor-related circRNAs and discuss their functioning in tumor progression and metastasis. These circRNAs are categorized into different functional mechanisms, including microRNA (miRNA) sponging, protein binding, regulation of host genes, translation of circRNAs, and exosomal circRNAs. Additionally, the indirect functions of circRNAs that regulate epithelial-mesenchymal transition and autophagy are also discussed.

Regulatory T cells (Tregs) serve an important role in the pathogenesis of rheumatoid arthritis (RA) by regulating autoimmunity and inflammation. Humans and mice contain inducible T‑cell costimulator‑positive (ICOS+) Tregs, although their role in RA is unclear. A total of 33 patients with RA and 17 normal control (NC) subjects were examined. The proportion of ICOS+ Tregs in the peripheral blood and intracellular cytokine levels in these cells were assessed using flow cytometry. The percentage of ICOS+ Tregs increased in the cohort of patients with RA compared with the NCs. Such increases were much larger in patients with inactive RA compared with patients with active RA. Additionally, ICOS+ Tregs expressed multiple suppressive cytokines, including interleukin (IL)‑10, transforming growth factor‑β and IL‑35, but expressed low levels of IL‑17. Importantly, the expression of suppressive cytokines in ICOS+ Tregs from patients with active RA decreased, but IL‑17 expression noticeably increased compared with patients with inactive RA. The present findings suggested that ICOS+ Tregs may perform inflammatory and inhibitory functions, and abnormal ICOS+ Tregs numbers and functions may contribute to the pathogenesis of RA.

The purpose of this retrospective cross-sectional study was to explore the clinical and pathogenic significance of vitamin D and its relationship with interferon-α (IFN-α) in Chinese patients with primary Sjögren’s syndrome (pSS). In our study, 32 pSS patients and 50 healthy controls were included. Serum vitamin D and IFN-α concentrations were determined by enzyme-linked immunosorbent assay (ELISA) and analyzed with the correlations of EULAR Sjögren’s Syndrome Disease Activity Index (ESSDAI). The multiple linear regression analysis of 25-OH vitamin D3 level with ESSDAI scores in pSS patients was also investigated. Serum 25-OH vitamin D3 significantly correlated in an inverse manner with ESSDAI scores (p < 0.001, r = −0.781) and IgG (p < 0.001, r = −0.64). Serum 25-OH vitamin D3 were only related to peripheral nervous system (PNS) domain deficiency. Further, serum IFN-α was positively correlated with ESSDAI, but negatively correlated with serum 25-OH vitamin D3. These results suggest an important role of vitamin D regulating disease activity in pSS patients and value of supplement vitamin D in pSS treatment.

Objectives: This retrospective study aims to characterise the epidemiological features of systemic lupus erythematosus (SLE) concomitant with chronic spontaneous urticaria (CSU), examines the correlation between CSU occurrence and lupus disease activity, and identifies comorbidity patterns and risk factors associated with SLE-CSU. Methods: A total of 40 SLE patients with concomitant CSU and 160 age-matched and sex-matched SLE controls without CSU were included. The Mann-Whitney U-test was used to assess disease activity at SLE onset in both groups. A Wilcoxon signed-rank test was conducted to compare the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores before and after CSU onset in patients with SLE. χ ² tests were applied to evaluate differences in SLE activity grading, clinical manifestations, laboratory findings and treatments between patients with SLE with and without CSU. In addition, univariate and multivariate logistic regression analyses were performed to identify risk factors for CSU development in patients with SLE. Results: Wilcoxon signed-rank tests revealed that in the SLE-CSU group, the occurrence of CSU did not result in an increase of SLEDAI scores. Univariate analysis revealed significant differences between the SLE-CSU and SLE-only groups in the presence of cylindruria, elevated IgM, IgA, IgG, serositis, mucosal ulcers and anti-Pm-Scl antibodies (p<0.05). Multivariate logistic regression analysis identified cylindruria (OR: 6.152, CI 2.352 to 16.093, p＜0.001), elevated IgA (OR: 7.598, CI 1.194 to 48.368, p=0.032), elevated IgG (OR: 3.252, CI 1.331 to 7.946, p=0.010) and mucosal ulcers (OR: 3.838, CI 1.166 to 12.637, p=0.027) as independent risk factors for CSU occurrence in patients with SLE. Conclusion: The presence of CSU in patients with SLE does not necessarily indicate increased lupus activity. Rather, cylindruria, mucosal ulcers and elevated IgA and IgG levels were identified as independent risk factors for CSU in patients with SLE.