Investigation of hub ferroptosis-related genes and the immune landscape in recurrent pregnancy loss and unexplained infertility using bioinformatics analysis

BACKGROUND: Recurrent pregnancy loss (RPL) and unexplained infertility (UI) are common pregnancy disorders that affect women's physical and mental health and lack effective treatment. Endometrial factors are one factor that leads to RPL. The latest research indicates that ferroptosis and immunity are closely related to the normal physiological function of the endometrium and may play a role in the pathogenesis of RPL and UI. Therefore, the present study analyzed the relationship between ferroptosis genes and immune infiltration in RPL and UI. METHODS: We downloaded the GSE165004 dataset and analyzed differences in ferroptosis-related genes (FRGs) between RPL and UI patients and healthy controls. Hub differentially expressed ferroptosis-related genes (DE-FRGs) were screened using the LASSO algorithm, the SVM-RFE algorithm and the protein-protein interaction (PPI) network. Differences in immune infiltration between healthy endometrium and RPL and UI endometrium was analyzed, and the relationship between hub DE-FRGs and immune cell infiltration was examined. RESULTS: We extracted 409 FRGs and identified 36 up-regulated and 32 down-regulated DE-FRGs in RPL and UI. Twenty-one genes were screened using the LASSO regression algorithm, and 17 genes were screened using the SVM-RFE algorithm. We intersected the LASSO genes, SVM-RFE genes and PPI network proteins to obtain 5 hub DE-FRGs. Gene set enrichment analysis (GSEA) functional enrichment analysis results indicated that the cytokine-cytokine receptor interaction signaling pathway was the common pathway for hub DE-FRGs. T follicular helper cells were highly infiltrated in RPL and UI, and M1 and M2 macrophages were highly infiltrated. The expression levels of MAPK1 and RELA positively correlated with T follicular helper cells. CONCLUSIONS: Ferroptosis-related genes may disrupt endometrial functions and signaling pathways and lead to the occurrence of RPL and UI.