RORC2 Genetic Variants and Serum Levels in Patients with Rheumatoid Arthritis

Background: In the present study, we aimed to evaluate whether polymorphisms within the RORc2 gene are involved in the risk and severity of rheumatoid arthritis (RA). Methods: 591 RA patients and 341 healthy individuals were examined for RORc2 gene polymorphisms. Serum retinoic acid receptor-related orphan receptor C (RORc) levels were measured by enzyme-linked immunosorbent assay (ELISA). Results: The rs9826 A/G, rs12045886 T/C and rs9017 G/A RORc2 gene SNPs show no significant differences in the proportion of cases and control. Overall, rs9826 and rs9017 were in high linkage disequilibrium (LD) with D’ = 0.952 and r2 = 0.874, except rs9826 and rs12045886; and rs12045886 and rs9017 in weak LD. The genotype–phenotype analysis showed a significant association between RORc2 rs9826 A/G and rs9017 G/A single nucleotide polymorphisms (SNPs) and median of C-reactive protein (CRP). Serum RORc levels was higher in RA patients with rs9826AA, rs12045886TT and -TC, and rs9017AA genotypes compared to healthy subjects with the same genotypes (p = 0.02, p = 0.04 and p = 0.01, respectively). Moreover, the median of RORc protein level was higher in RA patients with number of swollen joints bigger then 3 (p = 0.04) and with Health Assessment Questionnaires (HAQ) score bigger then 1.5 (0.049). Conclusions: Current findings indicated that the RORc2 genetic polymorphism and the RORc2 protein level may be associated with severity of RA in the Polish population

Relationship between VEGF Gene Polymorphisms and Serum VEGF Protein Levels in Patients with Rheumatoid Arthritis

<div><p>Background</p><p>Rheumatoid arthritis (RA) is one of the chronic autoimmune diseases, with genetic and environmental predisposition, and synovial angiogenesis is considered to be a notable stage in its pathogenesis. Angiogenesis or vascular proliferation has been suggested to be a pivotal mechanism involved in both inflammation/immune activation and joint invasion and destruction. RA may be considered an “angiogenic disease” because it is associated with active tissue neovascularization. Vascular endothelial growth factor (VEGF) promotes vascular permeability, regulates angiogenesis, endothelial cell proliferation and migration, chemotaxis, and capillary hyper permeability and therefore is involved in the development of inflammation. VEGF is the most potent proangiogenic molecule promoting the angiogenic phenotype of RA and is upregulated in RA.</p><p>Objectives</p><p>The aim of the study was to identify functional VEGF variants and their possible association with VEGF expression, susceptibility to and severity of RA.</p><p>Methods</p><p>581 RA patients and of 341 healthy individuals were examined for -1154 A/G, -2578 A/C VEGF gene polymorphisms by PCR-RFLP method and for -634 G/C VEGF gene polymorphisms by TaqMan SNP genotyping assay. Serum VEGF levels in RA patients and controls were measured by ELISA.</p><p>Results</p><p>The -1154 A/G VEGF gene polymorphism under the codominant, recessive (AA+AG vs. GG) and dominant (AA vs. AG+GG) models were associated with RA (p = 0.0009; p = 0.004; p = 0.017, respectively). VEGF -2578 A/C revealed differences in the case-control distribution in codominant, recessive, dominant and overdominant models (all p<0.0001). Furthermore, the -634 G/C VEGF gene SNP was not correlated with susceptibility to RA in Polish population. The genotype-phenotype analysis showed significant association between the VEGF -1154 A/G and -634 G/C and mean value of the hemoglobin (all p = 0.05), additionally they relevated that the number of women with the polymorphic allele -2578 C was lower than the number of women with wild type allele -2578A (p = 0.006). Serum VEGF levels were significantly higher in RA patients than in control groups (both p = 0,0001).</p><p>Conclusion</p><p>Present findings indicated that VEGF genetic polymorphism as well as VEGF protein levels may be associated with the susceptibility to RA in the Polish population.</p></div

Relationship between VEGF Gene Polymorphisms and Serum VEGF Protein Levels in Patients with Rheumatoid Arthritis - Fig 3

<p>Variation in VEGF expression levels in RA patients and control group in relation to: <b>A)</b>—1154 A/G (rs1570360) VEGF genotypes; <b>B)</b>—2578 A/C (rs699947) VEGF genotypes; <b>C)</b>—634 G/C (rs2010963) VEGF genotypes.</p

Correlation of VEGF protein expression level with the various clinical characteristics in RA.

<p>Correlation of VEGF protein expression level with the various clinical characteristics in RA.</p

Demographic and clinical characteristics of the RA patients with CVD and without CVD.

<p>Demographic and clinical characteristics of the RA patients with CVD and without CVD.</p

Distribution of genotypes and allele frequencies of VEGF SNPs among Polish patients with RA and healthy subjects.

<p>OR adjusted for sex and age.</p

<i>VEGF</i> haplotypes in rheumatoid arthritis (RA) patients and controls.

<p><i>VEGF</i> haplotypes in rheumatoid arthritis (RA) patients and controls.</p

Demographic and clinical characteristics of RA patients.

<p>Demographic and clinical characteristics of RA patients.</p

The disease activity and laboratory parameters in relation to <i>VEGF</i>-1154 A/G; recessive model.

<p>The disease activity and laboratory parameters in relation to <i>VEGF</i>-1154 A/G; recessive model.</p

Linkage disequilibrium (LD) plots of three SNPs in the VEGF gene.

<p>Linkage disequilibrium (LD) plots of three SNPs in the VEGF gene.</p