Association and Expression Study of PRKCH Gene in a French Caucasian Population with Rheumatoid Arthritis

PRKCH polymorphism is associated with rheumatoid arthritis in a Chinese population

Genetic factors have been widely considered to have a substantial effect on the susceptibility to rheumatoid arthritis (RA). The purpose of this study was to determine whether the four newly discovered polymorphisms in a genome-wide association study (GWAS) meta-analysis confer susceptibility to RA in a Chinese Han population. We conducted a case-control study involving 359 RA cases and 873 age-and gender-matched controls and performed genotyping of four single nucleotide polymorphisms (SNPs), rs227163, rs726288, rs3783782 and rs2469434, using the dye terminator-based SNaPshot method. Consequently, we detected significant differences of genotype distribution of rs3783782 in PRKCH between RA and controls. The minor allele frequencies (MAFs) of rs3783782 were significantly higher in RA patients compared to control subjects. Moreover, the rs227163 in TNFRSF9 had higher MAFs in male RA compared with male controls. In addition, the polymorphism of rs3783782 in PRKCH was significantly associated with RA susceptibility (OR = 1.67, 95% CI = 1.32-2.11, p = 1.32 × 10^-5). After stratification by gender, the minor (A) allele was strongly associated with increased risk for RA in males (OR = 1.87, 95% CI = 1.34-2.60; p = 1.62 × 10^-4) and in females (OR = 1.51, 95% CI = 1.08-2.10; p = 0.014). For rs227163, the minor (C) allele was found to be associated with RA risk only in males (OR = 1.34, 95% CI = 1.02-1.75; p = 0.036). These findings for the first time confirmed that rs3783782 in PRKCH was associated with RA susceptibility in a Chinese population, and rs227163 in TNFRSF9 was associated with RA risk in Chinese males; these SNPs may serve as genetic markers for RA.

Screening for Differentially Expressed Circular RNAs in the Cartilage of Osteoarthritis Patients for Their Diagnostic Value

Background: Osteoarthritis (OA) is the most prevalent osteoarticular disease, which typically involves chronic cartilage degeneration and synovitis. The latest research shows that circular RNAs (circRNAs) play a role in the development of a variety of diseases, including osteoarthrosis. Purposes: The aim of this study was to explore the expression of circRNAs in OA chondrocytes and predict biomarkers for diagnosis. Materials and Methods: The circRNA expression profile was analyzed through use of the Gene Spring software V13.0; differentially expressed circRNAs were screened by comparing OA chondrocytes and normal articular chondrocytes. We validated the microarray data by quantitative real-time polymerase chain reaction analyses of OA chondrocytes and chondrocytes from normal controls. TargetScan software and miRanda software were used to predict networks of circRNA-miRNA interactions in cartilage. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) analyses were applied to predict the functions of differentially expressed circRNAs. Results: Overall, 1380 circRNAs were differentially expressed between OA chondrocytes and normal articular chondrocytes (fold-change ≥2, p ≤ 0.05), including 215 that were upregulated and 1165 that were downregulated circRNAs. After analyzing the differentially expressed circRNA genes, the top 20 enriched GO entries and KEGG pathways were annotated. The hsa_circrna_0032131 was identified for further analysis. A circRNA-miRNA network was constructed to represent the 10 most likely target genes associated with the validated circRNA. Conclusions: Our research suggests that some of the differentially expressed circRNAs in OA chondrocytes compared to normal chondrocytes are etiologically associated with the pathological process of OA. It was found that hsa_circRNA_0032131 likely participates in the initiation and progression of OA and has potential as a diagnostic marker. Clinical Relevance: To analyze the difference of circRNA expression profiles between OA and normal controls and explore biomarkers for diagnosis.

Protein kinase C and its inhibitors in the regulation of inflammation: inducible nitric oxide synthase as an example

Protein kinase C (PKC) is a family of ten isoenzymes that play a crucial role in cellular signal transduction. Studies with PKC knockout animals have revealed that many of the isoenzymes are involved in cell growth, proliferation and differentiation. Several PKC isoenzymes have also been shown to be important mediators in inflammation and immunity, particularly in lymphocyte responses. However, less is known about the role of PKC in the regulation of the expression of inflammatory genes. In inflammatory processes, nitric oxide is primarily produced by inducible nitric oxide synthase (iNOS) in inflammatory cells, such as macrophages. In innate immunity, nitric oxide functions as an effector molecule towards the infectious organisms. Increased levels of nitric oxide are also produced by inflammatory and tissue cells in inflammatory diseases, such as asthma and arthritis. In this MiniReview, the role of PKC isoenzymes in the pathogenesis and as a potential drug target in inflammation will be discussed presenting iNOS as an example of an inflammatory gene regulated by the pleiotropic PKC signalling pathway.

Limited systemic sclerosis patients with pulmonary arterial hypertension show biomarkers of inflammation and vascular injury

Background

Pulmonary arterial hypertension (PAH) is a common complication for individuals with limited systemic sclerosis (lSSc). The identification and characterization of biomarkers for lSSc-PAH should lead to less invasive screening, a better understanding of pathogenesis, and improved treatment.

Methods and Findings

Forty-nine PBMC samples were obtained from 21 lSSc subjects without PAH (lSSc-noPAH), 15 lSSc subjects with PAH (lSSc-PAH), and 10 healthy controls; three subjects provided PBMCs one year later. Genome-wide gene expression was measured for each sample. The levels of 89 cytokines were measured in serum from a subset of subjects by Multi-Analyte Profiling (MAP) immunoassays. Gene expression clearly distinguished lSSc samples from healthy controls, and separated lSSc-PAH from lSSc-NoPAH patients. Real-time quantitative PCR confirmed increased expression of 9 genes (ICAM1, IFNGR1, IL1B, IL13Ra1, JAK2, AIF1, CCR1, ALAS2, TIMP2) in lSSc-PAH patients. Increased circulating cytokine levels of inflammatory mediators such as TNF-alpha, IL1-beta, ICAM-1, and IL-6, and markers of vascular injury such as VCAM-1, VEGF, and von Willebrand Factor were found in lSSc-PAH subjects.

Conclusions and Significance

The gene expression and cytokine profiles of lSSc-PAH patients suggest the presence of activated monocytes, and show markers of vascular injury and inflammation. These genes and factors could serve as biomarkers of PAH involvement in lSSc.