Zailong Xu,1,* Rui Ji,2,* Mei Wang,1 Tiantian Li,1 Hui Hu1 

1Department of Obstetrics and Gynecology, Pudong New Area People’s Hospital in Shanghai, Shanghai, People’s Republic of China; 2Department of Obstetrics and Gynecology, Shanghai Sixth People’s Hospital, Shanghai, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Hui Hu, Department of Obstetrics and Gynecology, Pudong New Area People’s Hospital in Shanghai, NO. 490 Chuanhuan South Road, Pudong New Area, Shanghai, 201200, People’s Republic of China, Email derhuizi@sina.com

Background: Endometriosis (EMS) is characterized by the occurrence, growth, infiltration, and recurrent bleeding of endometrial tissue outside the uterus. Recent studies have revealed a close association between Neutrophil Extracellular Traps (NETs) and the proliferation and metastasis of tumors. As EMS and tumours have similar biological behaviours, we hypothesised that key factors in tumourigenesis may also significantly influence the pathogenesis of EMS. Therefore, this study aimed to explore the potential link that exists between NETs and endometriosis.
Methods: A total of 190 patients were selected and divided into control and endometriosis groups (95 patients each) based on inclusion and exclusion criteria. Samples from ectopic and eutopic endometrium in the experimental group, eutopic endometrium in the control group, and peripheral blood serum and neutrophils (PMN) were collected and analyzed. ROC curve analysis was used to evaluate the diagnostic ability of NETs-associated markers to differentiate endometriosis patients from controls.
Results: The analysis of both patient groups revealed that levels of circulating free DNA (cf-DNA), nucleosomes, and neutrophil elastase (NE) were significantly higher in the experimental group compared to the controls. Further analysis indicated that the levels of NETs-related factors were elevated in patients with infertility and there was a positive correlation between pain severity and NETs markers in patients experiencing pain. Additionally, the ROC curve analysis demonstrated significant differences in cf-DNA, nucleosomes, and NE levels between the experimental and control groups (P < 0.05).
Conclusion: NETs-associated markers may be linked to endometriosis, likely due to their involvement in tumor proliferation and metastasis, which share similarities with endometriosis. Further studies are needed to explore the mechanisms connecting endometriosis and NETs markers.

Keywords: NETs, markers, endometriosis, infertility, case-control study