Bioinformatics analysis of differentially co-expressed genes in peripheral blood and hippocampal tissue of patients with Alzheimer’s disease

Abstract:

Objective To determine differentially co-expressed genes in the peripheral blood and hippocampal tissue of patients with Alzheimer’s disease（AD） by bioinformatics analysis，and to provide new ideas for AD diagnosis and therapeutic target selection.Methods We downloaded the AD-associated datasets GSE97760（9 cases of AD and 10 healthy controls） and GSE5281（10 cases of AD and 13 healthy controls） from the Gene Expression Omnibus（GEO） database for bioinformatics analysis. We selected differentially expressed genes（DEGs） in the peripheral blood and hippocampal tissues of patients with AD separately；identified the co-expressed DEGs in the two datasets； then performed Gene Ontology（GO） analysis and Kyoto Encyclopedia of Genes and Genomes（KEGG） pathway analysis on the co-expressed DEGs；and constructed a protein-protein interaction（PPI） network to further determine the key genes，followed by validation.Results Through the comprehensive analysis of the two GEO datasets，a total of 669 co-expressed DEGs were selected，including 64 up-regulated DEGs and 605 down-regulated DEGs. The GO and KEGG analyses selected 174 key items and 40 key pathways，respectively，which were significantly enriched mainly in the transcriptional regulation of RNA polymerase and glioma pathway. The PPI network determined 10 key AD-related genes：TP53，PTEN，HNRNPC，EIF4G1，SF3B1，SRSF11，PIK3R1，RBM39，LUC7L3，and RBM25，of which PTEN，HNRNPC，SF3B1，PIK3R1，and LUC7L3 were validated in the dataset GSE48350.Conclusion The five key genes（PTEN，HNRNPC，SF3B1，PIK3R1，and LUC7L3） selected in this study may serve as potential biomarkers for AD diagnosis，which deserve further research.