Identification of FZD7 as a potential ferroptosis-related diagnostic gene in endometriosis by bioinformatics analysis

Abstract

An increasing number of research have suggested that ferroptosis plays an important role in endometriosis (EMS). This study was to identify a ferroptosis-related diagnosis gene in EMS by using bioinformatics. R Bioconductor package limma was used to analyzed the differentially expressed genes (DEGs) between the EMS groups and control groups. CIBERSORT was used to analyze the differences between the EMS group and control group of 22 immune cells. Quantitative real-time PCR (RT-qPCR) and Western blot (WB) were used to validate the expression level of FZD7 in tissue samples. The study found that FZD7 was upregulated and showed good diagnostic value in five EMS transcriptome databases. RT-qPCR and WB experiments also verified that FZD7 was upregulated in EMS. Moreover, we found that macrophages, especially M2 macrophages, were significantly infiltrated in EMS. FZD7 was positively correlated with M2 macrophage infiltration, and was up-regulated in the endometrial stromal cells co-cultured with macrophages. The study identified an ferroptosis repressor gene, FZD7, validated in five EMS transcriptome datasets, which is significantly up-regulated in ectopic lesions of EMS and is a potential target for the treatment of EMS.

Keywords: Bioinformatics analysis; Endometriosis; FZD7; Ferroptosis.

Fig. 1

(A) Identification of differentially expressed genes (DEGs) between the EMS groups and control groups in GSE11691. (B) Heatmap of 30 differentially expressed genes (DEGs) that are considered as ferroptosis-related genes (FRGs) in GSE11691. (C) Venn diagram of the same differentially expressed genes (DEGs) from GSE11691, GSE7305, GSE5108, GSE23339 and GSE25628 datasets. (D) Identification of ferroptosis-related genes (FRG) in the same differentially expressed genes (DEGs) from GSE11691, GSE7305, GSE5108, GSE23339 and GSE25628 datasets.

Fig. 2

(A, C, E, G, I) FZD7 is significantly up-regulated in GSE11691, GSE7305, GSE5108, GSE23339 and GSE25628 datasets. (B, D, F, H, J) The receiver-operating characteristic (ROC) curve and the area under the curve (AUC) curve of FZD7 in GSE11691, GSE7305, GSE5108, GSE23339 and GSE25628 datasets.

Fig. 3

GO and KEGG pathways for the overlapping FZD7 positively associated genes in GSE11691, GSE7305, GSE5108, GSE23339 and GSE25628 datasets.

Fig. 4

(A, C) The infiltration of 22 immune cells in EMS of GSE11691dataset. (B) The relationship between FZD7 and 22 immune cells in GSE11691 dataset. (D) The expression of FZD7 in GSE19834. (E) Immunofluorescence images staining with CD206 in Vehicle group and F7H group.

Fig. 5

(A-C) The expression of FZD7 in ectopic (Ec) endometrial tissues, eutopic (Eu) endometrial tissues and normal endometrial (NE) tissues. **p < 0.01, ***p < 0.001, ns, no significant difference by one-way analysis of variance (ANOVA) test.