Objectives: Type 2 diabetes is a complex disease characterized by progressive β-cell failure. The primary mechanism underlying this failure is the progressive loss of pancreatic β-cell function. The aim of this study is to identify the key gene expression changes in human pancreatic isolated islets of patients with type 2 diabetes.

Methods: We extracted gene expression data in human pancreatic isolated islets of patients with type 2 diabetes and healthy controls from Gene Expression Omnibus (GEO) and analyzed it using GEO2R program. We then assessed the significant differentially expressed genes (DEGs) using protein-protein interaction (PPI) network analysis. The critical genes were enriched via gene ontology and discussed.

Results: Among the 93 significant DEGs, five critical genes including ITGB2, APOE, BIRC5, GABRA2, and IL1B were emerged as key players in type 2 diabetes. Notably, "Alzheimer disease, type 4" was identified as a major class of biological terms altered in type 2 diabetes.

Conclusions: Our findings suggest that the introduced critical genes are potential targets for controlling type 2 diabetes. Furthermore, the crucial role of APOE as a link between type 2 diabetes and Alzheimer's disease or other cognitive disorders was confirmed.