miRNAs and NFKB1 and TRAF6 target genes: The initial functional study in CD14+ monocytes in rheumatoid arthritis patients.

We predicted miRNAs with regulatory impact on NFKB1 and TRAF6 gene expression and selected the miR-194-5p, miR-124-3p, miR-9-5p, and miR-340-5p and their target genes for expression analyses on CD14+ monocytes from rheumatoid arthritis (RA) patients and healthy controls. Additionally, we evaluated the influence of genes and miRNA expression on RA patients' cytokine levels. No difference was observed in genes or miRNAs expression when compared to healthy controls and RA patients or clinical parameters. However, we found a significant difference between miR-194-5p and miR-9-5p levels (FC=-2.31; p=0.031; FC=-3.05;p=0.031, respectively) and non-prednisone users as compared to prednisone using patients. We conducted correlation analyses to identify the strength of the relationship between expression data and cytokine plasma levels. We observed a moderate positive correlation between miR-124-3p expression and IL-6 plasma levels (r=0.46; p=0.033). In addition, overexpression of miRNAs was concomitant to TRAF6 and NFKB1 genes as indicated by correlation analyses: TRAF6 and miR-194-5p (r=0.60;p<0.001) and miR-9-5p (r=0.63;p<0.001) and NFKB1 and miR-194-5p (r=0.72;p<0.001), miR-9-5p (r=0.72;p<0.001) and miR-340-5p (r=0.61;p<0.001). NFKB1 and TRAF6 genes and miRNAs monocyte expression do not appear to be related to RA but showed a significant difference in different groups of RA therapy. In addition, increased levels of miRNAs can be linked to concomitant overexpression of TRAF6 and NFKB1 in monocytes and act as its regulators.

CIITA gene polymorphism (rs3087456) in systemic lupus erythematosus and rheumatoid arthritis: A population-based cohort study.

Systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) are influenced by genetic variants in immune system HLA genes. The Class II Major Histocompatibility Complex Transactivator (CIITA) is an important co-activator of the HLA transcriptional complex; the single nucleotide variant (SNV) rs3087456 localized in the gene promoter region (-168 A/G) has been reported as able to modify its transcription level. In our study, we assessed CIITA rs3087456 SNV in 1,044 Brazilians from two Brazilian regions (Northeast and South) to verify the association with susceptibility and clinical manifestations of (SLE) and (RA) using TaqMan SNP Genotyping Assays System. We observed a protection for a recessive model (GG x AA+AG) for RA susceptibility and increased risk for erosion development in AG genotype patients. No significant association was observed for SLE susceptibility; however, we observed significant increased risk for Class IV and V nephritis development in G allele and GG genotype patients. In conclusion, we showed the contribution of CIITA rs3087456 to SLE or RA clinical features and RA susceptibility in the studied populations.

Expression of the miR-9-5p, miR-125b-5p and its target gene NFKB1 and TRAF6 in childhood-onset systemic lupus erythematosus (cSLE).

Childhood- onset systemic lupus erythematosus (cSLE) is a multisystem inflammatory disease that can lead to severe clinical conditions resulting in early comorbidities. Several genetic, environmental, and immunological factors are known to influence the onset of the disease. MiRNAs have been already considered as potential actors involved in the development and activity of the SLE. Thus, understanding the behavior of these regulators can contribute to clarify the inflammatory process affecting SLE patients. Among miRNAs, miR-125b-5p and miR-9-5p targeting NFKB1 and TRAF6 genes can be involved in the etio-pathogenesis of the disease by modulating inflammation. In this study we evaluated miR-9-5p and miR-125b-5p expression and its target genes NFKB1 and TRAF6 in peripheral blood samples (PBMC) from the 35 cSLE patients and 35 healthy controls. MiRNAs and gene target expression have been evaluated by using RT-PCR with specific TaqMan® probes. Both miR-9-5p [Fold Change (FC) = -2.21; p = 0.002] and miR-125b-5p (FC= -3.30; p < 0.0001) and NFKB1 (FC = -1.84; p < 0.001) were downregulated in cSLE patients, while TRAF6 was upregulated (FC = 1.80; p = 0.006) in cSLE patients when compared to controls. A significant correlation was found between miR-125b-5p and its target gene NFKB1 [Spearman (r) = 0.47; p = 0.023]. Our results showed miR-125b-5p and miR-9-5p differential expression in cSLE patients, possibly contributing to better understanding the role of these regulators in cSLE development and disease pathogenesis.