Abstract: Objective To explore the expression and function of DEP domain containing 1 (DEPDC1) in uterine corpus endometrial cancer(UCEC). Methods The Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases were used to analyze the expression of DEPDC1 mRNA in normal endometrial tissues and UCEC tissues, the relationship with patient clinicopathological parameters and prognosis. Immuno-histochemistry (IHC), Western blot and RT-qPCR were used to detect the expression of DEPDC1 in UCEC cell lines and tissue. The CCK-8 assay, colony formation assay, and tumor xenograft were used to investigate the effect of DEPDC1 on cancer proliferation. Results DEPDC1 mRNA was up-regulated in UCEC (P＜0.001) and was correlated with the clinical stages (P＜0.001), tissue differentiation (P＜0.05) and histological type(P＜0.001) of UCEC. Compared with the DEPDC1 mRNA low expression patients, the patients with high expression of DEPDC1 showed lower disease-specific survival(DSS) and progress-free interval (PFI) (P＜0.01). The IHC, Western blot, and RT-qPCR showed that DEPDC1 was up-regulated both in UCEC tissue and cell lines. Down regulation of DEPDC1 inhibited the colony formation, invasion and tumor sphere formation, cell proliferation rate, and tumourigenesis in vivo. Conclusions DEPDC1 is up-regulated in UCEC that is correlated with the malignant progression and poor prognosis of UCEC.

Key words: uterine corpus endometrial cancer, DEP domain containing 1 (DEPDC1), proliferation