Circadian rhythm genes and immune cell infiltration in myasthenia gravis: A comprehensive analysis

The fluctuating weakness in myasthenia gravis (MG) is clinically described as the "morning improvement and evening worsening" pattern; MG is commonly associated with sleep disorders. However, there remains a paucity of research investigating the relationship between MG and circadian rhythms. This study seeks to identify pivotal circadian rhythm genes (CRGs) and characterize immune cell infiltration in MG, while exploring their potential roles in MG pathogenesis. MG data were obtained from the Gene Expression Omnibus (GEO) database. Initially, differentially expressed circadian rhythm genes between MG and control samples were identified through differential expression analysis. Subsequently, to elucidate the functional roles of differentially expressed CRGs, we conducted Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. Finally, weighted gene co-expression network analysis (WGCNA) and least absolute shrinkage and selection operator (LASSO) regression were applied to identify the hub CRGs. The diagnostic utility of hub genes was evaluated using the receiver operating characteristic curve, and their protein expression levels in the serum of patients with MG were assessed utilizing enzyme-linked immunosorbent assay. Additionally, we examined the extent of immune cell infiltration in MG and explored its relationship with the identified hub genes. We analyzed the immune infiltration profile in MG and their correlation with the identified hub genes. The GO enrichment analysis revealed significant enrichment of differentially expressed genes in circadian rhythm-related biological processes. Our investigation identified two hub CRGs that exhibit high diagnostic specificity and sensitivity and are significantly upregulated in serum samples from MG patients. Furthermore, Immune cells were correlated with hub genes. Our findings suggest a potential circadian rhythm disorder in MG, which may offer novel biomarkers and therapeutic strategies for future research.