Much research efforts have been recently made to explore the biological functions of LGR4–6 in multiple human cancer types.18, 19, 20, 21 Interestingly, numerous studies have reported that LGR4–6 play crucial roles in activation of Wnt/β-catenin signaling via binding to R-spondins (Rspo1–4).22, 23, 24 However, the clinical significances and biological roles of LGR4–6 in ovarian cancers, as well as the regulatory functions of LGR4–6 on Wnt/β-catenin signaling in the context of ovarian cancers, have yet not to be elucidated. This evidence concerns the gene LGR4 and cancer.