High expression of CD73 as a poor prognostic biomarker in human colorectal cancer.

ABSTRACT

BACKGROUND AND OBJECTIVES: To investigate the expression dynamics of CD73 and its prognostic significance in human colorectal cancer (CRC). METHODS: CD73 expression dynamics were detected by Western blotting. Immunohistochemistry was used to examine the expression of CD73 in CRC tissues from two independent cohorts by tissue microarrays. The optimal cutpoint of CD73 expression was assessed by the X-tile program. RESULTS: Western blotting analysis demonstrated that CD73 expression in CRC was significantly higher than in normal colorectal tissues. According to the X-tile program, the cutpoint for high expression of CD73 in CRC was determined when CD73 expression index was more than 5.9. High expression of CD73 was observed in 44.8% and 50.4% of CRC in the training and validation cohorts, respectively. Overexpression of CD73 was significantly correlated with tumor differentiation, nodal status, American Joint Committee on Cancer stage. Patients with high expression of CD73 had a poorer overall survival rate compared with patients with low expression of CD73 in both cohorts. In multivariate Cox regression analysis, overexpression of CD73 was proven to be an independent prognostic biomarker for CRC. CONCLUSIONS: High expression of CD73 can be an independent and useful biomarker for predicting the poor survival of patients with CRC.