Biomarker role of CH25H and GYPE genes in osteoarthritis and rheumatoid arthritis

Osteoarthritis (OA) and rheumatoid arthritis (RA) are both joint diseases with many different causes. Inflammatory arthritis, also known as rheumatoid arthritis, is one of the most complex types of arthritis. Non-inflammatory arthritis, also known as osteoarthritis, is a disease caused when the cartilage between the joints begins to be damaged. Considering the different treatment approaches for OA and RA, an accurate diagnosis of the type of arthritis is very important. The present study was conducted with the aim of finding gene expression and introducing reliable molecular biomarkers for RA and OA.

The microarray dataset was obtained under the GSE27390 number. The samples included nine samples of mononuclear cells obtained from the bone marrow of RA patients, 10 samples of mononuclear cells obtained from the bone marrow of OA patients. Differential expression analysis between the OA and RA groups was performed using GEO2R, and genes with differential expression were separated by examining two factors such as logFC#1 and p.adj. Value<0.05. Signaling pathways were determined using Enrichr databases. Next, the genes with the most expression changes were introduced. This study is a bioinformatics analysis and was conducted jointly at Bam University of Medical Sciences and Rajaie Cardiovascular, Medical and Research Institute from September 2022 to March 2023.

The results showed that, 5083 genes had significant expression differences. Analysis of signaling pathways showed that antigen processing and presentation,  natural killer cell-mediated cytotoxicity, the, IL-17 signaling pathway, Th17 cell differentiation and cytokine-cytokine receptor interaction, as inflammatory pathways, were important in this disease. It was also determined that CH25H (upregulated in RA samples) and GYPE (downregulated in RA samples) genes can distinguish rheumatoid arthritis from osteoarthritis.

Since accurate diagnosis helps with better disease treatment, it is very important to obtain new biological diagnostic markers. Overall, our data showed that genes can act as novel biomarkers with potential utility in the diagnosis of RA and OA and can be considered novel molecular biomarkers for the diagnosis of these two diseases.