Functions of RhoA in the female reproductive system

The Ras homolog gene family member A (RhoA) is a small GTPase. RhoA plays major roles in cytoskeletal regulation, transcriptional control, and cell cycle maintenance. RhoA is widely expressed in the female reproductive system (FRS). In vitro studies have implicated RhoA in several FRS functions and studies defining the in vivo functions of RhoA in the FRS are emerging. In the ovary, RhoA is essential for corpus luteum development and progesterone synthesis and is implicated in ovarian cancer. Some studies on the oviduct/fallopian tube suggest potential functions of RhoA in post-ovulation cumulus cells and embryo transport. In the uterus (corpus uterus), RhoA may be involved in embryo implantation (eg, decidualization) and parturition (eg, uterine contraction) and is also implicated in uterine disorders (eg, endometriosis and leiomyoma). Downregulation of RhoA in the cervix is correlated with cervical ripening during parturition, and numerous studies have implicated RhoA in cervical cancer. In the placenta, RhoA is implicated in preeclampsia and placenta accreta. In the vagina, RhoA downregulation correlates with vaginal smooth muscle relaxation and sexual response. RhoA in the mammary glands has been implicated in development and lactation as well as breast cancer. RhoA signaling is a potential therapeutic target for managing pathological conditions of the FRS. This review provides a comprehensive coverage of the current understanding of the spatiotemporal functions of RhoA in the FRS. Extensive knowledge regarding the in vivo cell type- and stage-specific functions of RhoA in FRS remains to be elucidated.