Expression of Peripheral Blood PD-1 and its Clinical Significance in Patients with Colorectal Cancer / 胃肠病学

ABSTRACT

Background:The abnormal expression of costimulatory molecules is closely related to immune escape of tumor cells. Programmed death-1(PD-1)is an important negative costimulatory molecule,and can induce and maintain the immune tolerance of tumor cells by binding with related ligands,thus promotes the development and progress of tumor. Aims:To investigate the expression of peripheral blood PD-1 and its clinical significance in patients with colorectal cancer. Methods:Eighty-eight patients with colorectal cancer from March 2015 to September 2015 at the First Affiliated Hospital of Soochow University were enrolled,and 16 healthy volunteers were served as controls. Level of soluble PD-1(sPD-1)was determined by ELISA. The expression of PD-l on CD3 + T cells in peripheral blood was measured by flow cytometry. Results:Level of sPD-1 and expression of PD-l on CD3 + T cells in peripheral blood in colorectal cancer patients were significantly higher than those in controls(P ﹤ 0. 05). Level of sPD-1 in colorectal cancer patients was closely related to tumor differentiation,lymph node metastasis and Dukes’stage( P ﹤ 0. 05),but not related to gender,age and tumor location(P ﹥ 0. 05). Conclusions:Peripheral blood PD-1 is highly expressed in patients with colorectal cancer,and is positively correlated with tumor stage and metastasis. The detection of PD-1 is helpful to estimate the progress of colorectal cancer,and it may become a new tumor marker or a target for anti-tumor targeted therapy.