Journal of Visualized Experiments · Nov 3, 2026
FOS and SGK1 as Senescence-Associated Hub Genes in Osteoarthritis: A Bioinformatics and Experimental Validation Study
By Huang C, Zhang H, Wang X et al.
Osteoarthritis (OA) is a highly prevalent degenerative joint disease, and the molecular mechanisms underlying its development and progression remain incompletely understood. This study aimed to identify cellular senescence (CS)-associated hub genes and signaling pathways involved in OA and to evaluate their potential biological significance. Two Gene Expression Omnibus (GEO) datasets (GSE51588 and GSE236924) were analyzed to identify CS-associated differentially expressed genes (DEGs). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed, followed by construction of a protein-protein interaction (PPI) network. Hub genes were identified using the cytoHubba plugin in Cytoscape, and drug enrichment analysis was conducted to identify compounds targeting the selected hub genes. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic performance of the candidate genes. The bioinformatics findings were further evaluated using in vitro chondrocyte experiments and an anterior cruciate ligament transection (ACLT) rat model of OA. Six hub genes (FOS, SGK1, DDIT4, EIF4EBP1, SOD2, and NAMPT) were identified, with enrichment primarily in the phosphoinositide 3-kinase/protein kinase B/mechanistic target of rapamycin (PI3K/AKT/mTOR) signaling pathway. Western blotting and quantitative polymerase chain reaction (qPCR) analyses demonstrated increased expression of FOS and SGK1 under inflammatory conditions. LY294002, identified through drug enrichment analysis as a pan-PI3K inhibitor, was associated with reduced SGK1 expression and attenuation of OA-related pathological changes. These findings identify FOS and SGK1 as senescence-associated hub genes that are associated with chondrocyte senescence and the PI3K/AKT/mTOR signaling pathway, providing candidate molecular targets for further investigation of OA pathogenesis.