Identification of potential hub genes related to ferroptosis and hypoxia in dilated cardiomyopathy: a bioinformatic analysis with preliminary experimental validation

The study aims to explore the potential role of ferroptosis and hypoxia in dilated cardiomyopathy (DCM). GSE120895, GSE17800, GSE112556, ferroptosis-related genes (FRGs), and hypoxia-related genes (HRGs) were downloaded from the public dataset. Ferroptosis- and hypoxia-related differentially expressed genes (DEGs) and DCM-related genes were obtained. Subsequentially, hub genes were identified, and their diagnostic values were assessed. Next, immune cell infiltration analysis, drug prediction and molecular docking were carried out based on the hub genes. Finally, the hub gene TGM2 was preliminarily verified <i>in vitro</i>. A total of 18 ferroptosis- and hypoxia-related DEGs and 315 DCM-related genes were acquired. Subsequently, 6 hub genes (PPP1R15A, TGM2, MAP3K5, USP7, SESN2, and ADAM23) were obtained and have potential diagnostic value. Immune infiltration analysis showed that CD56dim natural killer (NK) cells, macrophages, monocytes, NK cells, and NK T cells were significantly infiltrated in DCM patients. Furthermore, the lncRNA-miRNA-mRNA network was constructed. Moreover, 16 drugs were predicted, and the binding energy between atorvastatin and TGM2 was -2.79 kcal/mol. <i>In vitro</i> verification showed that TGM2, PPP1R15A and SESN2 were up-regulated in DOX-induced AC16 cardiomyocyte injury. After knocking down TGM2, the expressions of α-actinin and cTnT were increased, and the expression level of HIF-1α was inhibited. Dual luciferase assay showed that hsa-miR-291-5p exerted its regulatory effect by directly binding to TGM2. Flow cytometry results showed that TGM2 had no significant effect on the apoptosis of AC16 cells. Our findings may provide new ideas for the diagnosis and treatment of DCM.