Recurrent miscarriage (RM) is a chronic, heterogeneous autoimmune disease that has serious social and personal consequences. No valid and reliable diagnostic markers or therapeutic targets for RM have been identified. Macrophages impact the innate immune system and can be used as diagnostic and prognostic markers for many diseases. We first collected 16 decidua and villi tissue samples from 5 normal patients and 3 RM patients for single-cell RNA sequencing data analysis and identified 1293 macrophage marker genes. We then screened a recurrent miscarriage cohort (GSE165004) for 186 macrophage-associated marker genes that were significantly differentially expressed between RM patients and the normal pregnancy endometrial tissues, and performed a functional enrichment analysis of differentially expressed genes. We then identified seven core genes (ACTR2, CD2AP, MBNL2, NCSTN, PUM1, RPN2, and TBC1D12) from the above differentially expressed gene group that are closely related to RM using the LASSO, Random Forest and SVM-RFE algorithms. We also used GSE26787 and our own collection of clinical specimens to further evaluate the diagnostic value of the target genes. A nomogram was constructed of the expression levels of these seven target genes to predict RM, and the ROC and calibration curves showed that our nomogram had a high diagnostic value for RM. These results suggest that ACTR2 and NCSTN may be potential targets for preventative RM treatments.

Ovarian folliculogenesis is a complex biological process critical for female fertility, intricately regulated by various signaling pathways, among which the Mitogen-Activated Protein Kinase (MAPK) signaling pathway plays a pivotal role. This review provides a comprehensive overview of the physiological functions of MAPK signaling in key stages of folliculogenesis, including primordial follicle formation and activation, dominant follicle selection, cumulus-oocyte complex (COC) expansion, ovulation, and luteinization. The orchestrating roles of MAPK on steroidogenesis and ovarian cell death are also delineated, highlighting its essential contributions to normal reproductive function. Furthermore, we explore the implications of dysregulated MAPK signaling in ovarian aging, primary ovarian insufficiency (POI), polycystic ovary syndrome (PCOS), and ovarian hyperstimulation syndrome (OHSS). By elucidating the multifaceted roles of MAPK signaling in ovarian biology, this review aims to enhance our understanding of folliculogenesis and its associated pathologies, paving the way for future research and therapeutic interventions targeting MAPK pathways in reproductive health. Clinical trial number Not applicable.

In the endometrium of women with recurrent implantation failure and unexplained recurrent miscarriage, the expression levels of homeobox A10 and E-cadherin were positively correlated. To explore whether homeobox A10 regulates E-cadherin during endometrial receptivity establishment, Ishikawa and RL95-2 cells were transfected with target-specific small interfering RNA (siRNA) and overexpression plasmid of homeobox A10. The expression levels of homeobox A10 and E-cadherin were measured by western blot and quantitative Real-time Polymerase Chain Reaction (qRT-PCR). Attachment assay of JEG-3 spheroids to endometrial cells were conducted to explore the adhesive functions after homeobox A10 interfered. Chromatin immunoprecipitation assays and dual luciferase reporter were used to investigate the regulatory mechanism of homeobox A10. The CD1 mice were transfected with si-homeobox A10 to confirm these results in vivo. In Ishikawa and RL95-2 cells, the expression of E-cadherin was positively correlated with homeobox A10 when it was silenced/overexpressed. Consistently, the adhesion of endometrial epithelium cells and trophoblast cells was inhibited after homeobox A10 was silenced, and exogenous restoration of E-cadherin expression reversed this effect to some extent. Homeobox A10 regulates the expression of E-cadherin by directly binding to a conserved motif (TGTACTAAAAA) located in the E-cadherin promoter region. In addition, after knockdown of homeobox A10 in CD1 mice, both the implantation and live birth rates were decreased. In conclusion, homeobox A10 can bind to the E-cadherin promoter region and directly regulate its expression, thereby improving endometrial receptivity and subsequently increasing the embryo adhesion and implantation.