Abstract: OBJECTIVE:To investigate associations between expression of Forkhead box protein (FoxO1) and prognosis of prostate cancers (PCa). METHODS: FoxO1 expression data and the corresponding clinical data of PCa patients were downloaded from The Cancer Genome Atlas (TCGA). Expressions of FoxO1 mRNA in PCa tissues were measured by using the GEPIA database. Statistical analyses were performed for relationships between the expression and clinic-pathological factors and prognosis. Cox regression model was performed for the multivariate analysis. The Human Protein Atlas (HPA) was used to measure the UBE2C protein expression. RESULTS: Expression of FoxO1 mRNA was reduced in PCa compared to normal prostate tissues. The expression levels were correlated with the depth of tumor invasion, distant metastasis and degree of differentiation. The disease-free survival rates of patients with high FoxO1 expression were significantly higher than that of patients with low expression (P<0.05). Cox regression analyses show that the depth of tumor invasion and differentiation, and the expression of FoxO1 were independent prognostic factors for prostate cancers (P<0.05). Compared with the normal prostate tissues,immuno-histochemical staining show that FoxO1 expressions were significantly down-regulated in the PCa tissues (P<0.05). CONCLUSION:FoxO1 may be a tumor suppressor gene which can possibly provide the reference value for diagnosis and survival prognosis of patients with prostate cancer.

Key words: prostate cancer, cancer genome atlas, FoxO1, prognosis