The identification of sex-specific biomarkers in peripheral blood mononuclear cells from elderly individuals with ischemic stroke.

OBJECTIVE: The aim of this study was to identify sex-specific biomarkers for ischemic stroke (IS) prophylaxis in elderly individuals.

MATERIALS AND METHODS: The GSE22255 dataset for elderly individuals with IS was retrieved from the gene expression omnibus database. Thereafter, gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed, as well as gene set enrichment analysis (GSEA). Furthermore, protein-protein interactions (PPIs) were explored using the STRING database, and to screen central genes from the Cytoscape PPI network, corresponding to peripheral blood samples from elderly individuals, we used the molecular complex detection plug-in and cytoHubba. Moreover, a Venn diagram was used to visualize the key genes common among elderly women and men with IS. Statistical analysis was also performed, and receiver operating characteristic (ROC) curves were constructed to evaluate the specificity and sensitivity of the prediction of IS in the elderly.

RESULTS: Compared with the healthy controls, in elderly women with IS, 511 biological process (BP) terms, 16 molecular function (MF) terms, and 34 KEGG terms were significantly enriched, whereas in the elderly men with IS, 681 BP terms, 12 MF terms, and 44 KEGG terms were enriched. The GSEA revealed 99 and 140 significantly enriched gene sets in elderly women and men with IS, respectively. Furthermore, in the PPI network, 10 hub genes for each sex with high specificity and sensitivity were identified using ROC curves.

CONCLUSIONS: Ten genes for each sex with significant differential expression were also identified in individuals with IS. The novel sex-specific gene targets may be promising diagnostic or prognostic markers and potential therapeutic targets for IS in the elderly.