Circulating miRNAs in Murine Experimental Endometriosis: Decreased Abundance of let-7a

Endometriosis is a chronic disease that commonly affects women of reproductive age; however, diagnosis is often delayed due to lack of appreciation of early signs and symptoms. Development of a noninvasive biomarker would significantly reduce delays in diagnosis and treatment. Circulating microRNAs (miRNAs) have been implicated as biomarkers for several diseases including endometriosis. Here, we use an miRNA array to investigate differential miRNA abundance in the serum of mice after induction of experimental endometriosis. let-7a-5p was decreased in the serum of mice with endometriosis. let-7b-5p, c-5p, and e-5p also showed a trend toward downregulation. Serum let-7 family miRNA shows similar dysregulation in endometriosis in both humans and mice. Diminished circulating let-7 implies a complex regulation that potentially involves multiple organs. Further investigation is necessary to determine the functional roles of let-7 miRNAs in this disease.