Abstract: Objective To analyze the expression of centromere protein U (CENPU) in colorectal cancer and its predictive value for long- term prognosis of the patients. Methods We retrospectively analyzed the data of 102 patients with colorectal cancer undergoing radical resection in our hospital between January, 2005 and December, 2011. The expression level of CENPU in colorectal cancer tissue was detected immunohistochemically, and its association with clinicopathological characteristics of the patients were analyzed. The patients were divided into low expression group (n=51) and high expression group (n=51) based on the median CENPU expression level for analysis the value of CENPU for predicting long- term prognosis of the patients after radical resection of the tumors. In the in vitro study, we constructed colorectal cancer cell lines with CENPU interference and CENPU overexpression by lentiviral transfection and assessed the changes in the proliferation, migration and invasion of the cells using CCK-8 assay and Transwell assay. Results The protein expression level of CENPU was significantly higher in colorectal cancer tissues than in the adjacent tissues (P<0.05) and was positively correlated with the expressions levels of Ki67 (r=0.569, P<0.05) and VEGF- C (r=0.629, P<0.05). CENPU expression level in colorectal cancer tissue was closely related with tumor progression and clinicopathological stage of the tumor (P<0.05). Kaplan-Meier survival analysis showed that the patients with high CENPU expression had significantly decreased postoperative overall survival (χ2=11.155, P<0.05); Cox multivariate regression analysis suggested that CENPU expression level was an independent risk factor affecting the overall survival of the patients after radical resection (HR=1.848, P<0.05). The results of cell experiments demonstrated that high CENPU expression significantly promoted the proliferation, migration and invasion of the tumor cells. Conclusion CENPU is highly expressed in colorectal cancer tissues in closely correlation with tumor progression and may serve as a potential biomarker for evaluating the long-term prognosis of colorectal cancer patients.

Key words: colorectal cancer; CENPU; clinicopathological parameters; survival analysis; risk factor analysis