PD-1 and PD-L2 expression predict relapse risk and poor survival in patients with stage III colorectal cancer.

Abstract

Immune responses have long been an area of interest in cancer research. In this study, the effects of programmedcell death-1 (PD-1) and its ligand (PD-L2)on the prognosis of colorectal cancer (CRC) were investigated. Primary tumour specimens of stage III CRC patients operated between 2002 and 2013 were assessed for PD-1 and PD-L2 expression and various clinicopathological and prognostic factors. We observed a significant relationship between poor prognostic factors and PD-1/PD-L2 expression. These biomarkers were also found to serve as independent risk factors for LIR and MSI. In univariate analysis, relapse-free survival (RFS) and overall survival (OS) rates were found to be poor in PD-1 and PD-L2positive patients. In multivariate analysis, these biomarkers were found to serve as independent poor prognostic factors for RFS and OS. Our data indicate that PD-1 and PD-L2may serve as independent prognostic survival parameters for CRC patients and may be employed for the design of targeted therapies.