Immunoreactivity of Plasminogen Activator Inhibitor 1 and Its Correlation with Dysmenorrhea and Lesional Fibrosis in Adenomyosis

Adenomyosis is associated with dysmenorrhea, infertility, and lesional fibrosis. The pathogenesis of adenomyosis is still unclear. Plasminogen activator inhibitor 1 (PAI-1) plays important roles in pathological activities like tumor metastasis and endometriosis. Our objective was to investigate the expression and localization of PAI-1 in eutopic and ectopic endometrium with adenomyosis and in endometrium without adenomyosis. We also sought to determine the relationship between PAI-1 immunoreactivity and the severity of dysmenorrhea and the extent of lesional fibrosis in adenomyosis. PAI-1 expression was significantly higher in the ectopic endometrium of patients with adenomyosis than in both the eutopic endometrium of patients with adenomyosis and the endometrium of controls. Ectopic PAI-1 expression correlated positively with dysmenorrhea visual analog scale (VAS) scores and the extent of lesional fibrosis in adenomyosis. High PAI-1 expression increased the likelihood of moderate to severe dysmenorrhea in adenomyosis. These results suggest that PAI-1 is involved in the adenomyosis-associated dysmenorrhea and lesional fibrosis, which provide a potential target in treating symptomatic adenomyosis. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s43032-021-00513-6.