This study aimed to explore the effects of endometriosis (EMS)-derived exosomes and miR-301a-3p on the polarization of macrophages and investigate the involved molecular mechanism. The exosomes were isolated from ectopic endometrial tissues of EMS patients and normal human serum (NHS). Results of transmission electron microscope and Nanoparticle Tracking Analysis showed that both EMS-exosomes and NHS-exosomes are about 80 nm microvesicles. Exosomal markers CD63 and TSG101 were abundantly expressed in both EMS-exosomes and NHS-exosomes. No negative marker Calnexin was detected in NHS-exosomes. A small amount of Calnexin was detected in EMS-exosomes. THP-1 cells differentiatee to macrophages by incubating with phorbol-12-myristate-13-acetate. Effects of the exosomes on the phagocytosis and polarization of macrophages were evaluated by PKH26 fluorescent labeling and flow cytometry, respectively. Compared with the NHS-exosomes group, the phagocytic capacity of macrophages was reduced and the polarization of macrophages to M2 macrophages was promoted after EMS-exosomes treatment. Results of western blot showed that compared with the NHS-exosomes group, the EMS-exosomes treatment significantly up-regulated the expression of phosphatidylinositol 3-kinase (PI3K) and down-regulated the expression of phosphatase and tensin homologue deleted on chromosome 10 (PTEN). miR-301a-3p mimic, negative control (NC) mimic, miR-301a-3p inhibitor and NC inhibitor were transfected into cells. Transfection efficiency was confirmed by RT-qPCR. Effects of the miR-301a-3p expression on the macrophages polarization and the expression of Arg-1, PTEN and PI3K in the macrophages were evaluated by flow cytometry and western blot, respectively. miR-301a-3p overexpression significantly enhanced the ability of EMS-exosomes-inducing M2 transformation of macrophages, promoted the expression of Arg-1 and PI3K, and inhibited the PTEN expression. miR-301a-3p inhibitor significantly reduced the expression of Arg-1 and PI3K and promoted the PTEN expression. In conclusion, EMS derived exosomal miR-301a-3p mediated macrophage polarization via regulating PTEN-PI3K axis.

Polycystic ovary syndrome (PCOS) is a known risk factor for uterine endometrial cancer (UCEC), but its underlying mechanisms remain unclear. MicroRNAs (miRNAs) could provide insights into these mechanisms and reveal potential therapeutic targets. Differential miRNA expression was analyzed in plasma exosomes from 15 PCOS and 15 control samples. Survival analysis assessed the prognostic value of these miRNAs in UCEC. MiRNA-target gene interaction networks and gene co-expression analyses were used to explore molecular mechanisms. Validation was performed using experimental data from Ishikawa cells treated with six candidate drugs. Among the 15 differentially expressed miRNAs, 12 were up-regulated and 3 were down-regulated in PCOS. Twelve of these miRNAs were associated with UCEC overall survival, with miR-142, miR-424, and miR-331 acting as protective factors, while the remaining 9 miRNAs were identified as risk factors. MiRNA-target network highlighted key genes such as PHF8, LCOR, SFT2D3, E2F1, and ESR1, which were found to be prognostic for patient survival. Further gene expression and co-expression analyses based on miR-424 and miR-330 expression revealed significant alterations in gene expression and cellular processes related to UCEC. Two-sample Mendelian randomization analysis identified potential causal relationships between AURKA gene expression and PCOS or UCEC. Testosterone and estradiol might have adverse roles in UCEC, while drugs like troglitazone, valproic acid, retinoic acid, and progesterone demonstrated various effects on gene expression and cellular processes. Our findings suggest that aberrant miRNA expression, particularly miR-330 and miR-424, may play crucial roles in UCEC progression. The identified miRNAs and candidate drugs may serve as potential therapeutic targets for UCEC, but further research is required to validate and explore their clinical applications.