A possible Molecular Mechanism of Adenomyosis

Adenomyosis, an estrogen-dependent inflammatory disease, is defined as the presence of endometrial glands and stroma deep within the myometrium [1]. The main clinical features of adenomyosis are dysmenorrhea and menorrhagia, which are significantly associated with peritoneal endometriosis in infertile patients at reproductive age [2,3]. The only difference between adenomyosis and endometriosis is the site of endometriotic tissues, that is, inside or outside the uterus [4]. Thus, knowledge on the endometriotic cell origin is indispensable for the development of preventive and targeted treatment strategies for adenomyosis. The most widely accepted theory on the pathogenesis of adenomyosis is the down growth and invagination of the endometrium into the myometrium [5]. However, the possible mechanism of gland invagination from the endometrium deep into the underlying myometrium is unknown.