Objective:To analyze the relationship between peripheral blood T lymphocyte subsets, cell surface programmed death receptor 1 (PD-1) and prognosis in patients with gastric cancer. Methods:Seventy-five patients with gastric cancer were selected as gastric cancer group, and 30 healthy people undergoing physical examination in our hospital were served as control group. The relationship between the changes of CD3+, CD4+, CD8+, CD4+/CD8+ ratio and PD-1 levels in peripheral blood T lymphocytes and the prognosis of gastric cancer patients was analyzed. Results:The levels of CD8+ and PD-1 in peripheral blood T lymphocytes of the gastric cancer group were significantly higher than those in the control group, while the levels of CD3+, CD4+ and CD4+/CD8+ were significantly lower than those of the control group (P<0.05). CD8+ and PD-1 expressions in peripheral blood T lymphocyte of the death group were significantly higher than those in the survival group, while the levels of CD3+,CD4+ and CD4+/CD8+ ratio were significantly lower than those in the survival group (P<0.05). Multiariable COX regression analysis showed that the levels of CD3+, CD4+, CD8+, CD4+/CD8+ ratio in peripheral blood, PD-1, age and tumor stage were independent risk factors for prognosis in patients with gastric cancer. The levels of CD8+ and PD-1 were positively correlated with the prognosis of patients with gastric cancer while the levels of CD3+, CD4+, CD4+/CD8+ were negatively correlated with the prognosis. Conclusion:CD8+ and PD-1 expressions in T lymphocyte subsets are significantly increased in patients with gastric cancer. Combined detection of the levels of PD-1 and T lymphocyte subsets can effectively assist doctors to assess patients with gastric cancer, which is worth clinical application.
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