Serum miR-210 and miR-155 expression levels as novel biomarkers for rheumatoid arthritis diagnosis.

BACKGROUND: MicroRNAs play a crucial role in the regulation of immune response. We hypothesised roles for serum miR-210 and miR-155 in the diagnosis of rheumatoid arthritis (RA) and relationships with the clinical and laboratory variables including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor (RF), anti-cyclic citrullinated peptide (CCP) antibodies, tumour necrosis factor-alpha (TNF-α) and interleukin-1ß (IL-1ß). METHODS: MiR-210 and miR-155 levels were identified by real-time polymerase chain reaction (PCR). TNF-α and IL-1ß were measured by enzyme-linked immunosorbent assay and routine markers by standard techniques in 100 patients with RA and 100 individuals as healthy controls. Disease activity in the patients was assessed by DA-S28. RESULTS: MiR-210 was lower in RA compared to controls [median/IQR 0.96 (0.8-1.24) vs. 4 (1.28-3.93), p < 0.001]. miR-210 correlated inversely with clinical and laboratory variables including TNF-α and IL-1ß (both r = -0.96, p < 0.001). MiR-155 expression was increased in RA compared to controls [median/IQR 6 (3.5-8.1) vs. 1.0 (0.95-1.6), p < 0.001] and correlated with TNF-α and IL-1ß (both r = 0.94, p < 0.001). In multivariate analysis, miR-210 and miR-155 were both independent diagnostic markers for RA, and both were associated with RA disease activity. CONCLUSION: Serum miR-210 and miR-155 levels are independent diagnostic markers for RA, out-performing several routine indices and reflect disease activity. Thus, miR-210 and miR-155 might serve as non-invasive biomarkers for the diagnosis of RA.

Cyclooxygenase-2 169C>G and 8473T>C gene polymorphisms and prostaglandin E2 level in breast cancer: a case-control study.

AIMS: Cyclooxygenase 2 (COX-2) with the resulting prostaglandin E2 (PGE2) is linked to increased risk of human breast cancer (BC). The aim of this study was to determine COX-2 169C>G and 8473T>C gene polymorphisms and PGE2 level at various stages of BC clarifying the role of COX-2 gene polymorphism and PGE2 in relation to BC. METHODS: The study population comprised 160 women at different stages of BC and 150 gender- and age-matched healthy control subjects. Plasma PGE2 was measured by ELISA, the COX-2 gene polymorphisms were determined using PCR-RFLP. RESULTS: The variant alleles COX-2 169G and 8473C were significantly associated with BC susceptibility [OR=3.1, 95% CI (2.2-4.4), P<0.001 for 169C>G and OR=1.74, 95%CI (1.3-2.4), P=0.005 for 8473C]. However, both COX-2 gene polymorphisms were not associated with breast cancer stage. Plasma PGE2 levels were significantly increased in patients compared to the controls. In early and late stages of BC, there was a significant increase in the plasma PGE2 levels towards the presence of homozygous GG compared with homozygous CC (P<0.001) for 169 C>G, also towards the presence of CC than TT (P<0.001) for 8473T>C SNP. CONCLUSION: The 169C>G and 8473T>C polymorphisms of the COX-2 gene were associated with the BC in Egyptian women. Furthermore, individuals with COX-2 169GG and 8473CC genotypes showed significant increase in plasma PGE2 levels. PGE2 levels may serve as a predictor of poor prognosis in patients with BC.