Expression of Alpha-Enolase 1 (ENO1) in Villi from Patients with Recurrent Miscarriage and Its Effect on Proliferation and Invasion of Villous Trophoblasts

Recurrent miscarriage (RM) is a common reproductive endocrine disease in women of childbearing age. At present, the etiology of RM in approximately 50% women remains unknown. The purpose of this study was to explore the possible mechanism(s) of enolase 1 (ENO1) in RM and to seek a new target for clinical diagnosis and treatment of the disease. In this study, we detected the expression difference of ENO1 in villous tissues between the RM group and the control group, and we found that ENO1 was significantly lower in the RM group. Immunohistochemistry was also performed to examine the localization and expression of ENO1 in villous cytotrophoblast cells, and we found that ENO1 was mainly expressed in the cytoplasm, cell membrane, and nucleus of trophoblast cells. The villous trophoblast cell membrane coloration in the control group was significantly darker than that in the RM group, suggesting that ENO1 is expressed at low levels on the cell membrane of trophoblast cells of RM. ENO1 knockdown significantly inhibited cell migration and proliferation compared with the blank control group. Therefore, we conclude that ENO1 may mediate the occurrence of RM by downregulating the proliferation and invasion of villous trophoblasts. The specific mechanism needs further clarification.