Expressions of CXCR3 and PD-1 on T cells and their clinical relevance in colorectal cancer

Purpose: Clinical application of immunotherapy represented by Programmed Death -1 (PD -1) monoclonal antibody has changed the treatment paradigm for colorectal cancer (CRC), and tumor -infiltrating T lymphocytes are critical for anti -PD -1 therapy in CRC. However, there are few studies on the relationship between the expression CXCR3 on T lymphocytes and the clinical aspects of CRC. In this study, we analyzed the expression levels of CXCR3 and PD -1 in CD8 + and CD4 + T lymphocytes in healthy donors (HDs) and patients with CRC. Methods: We detected the expressions of CXCR3 and PD -1 on T lymphocytes in peripheral blood of healthy donors as well as peripheral blood, tumor tissue and para -cancerous tissues of patients with CRC using flow cytometry. We also analyzed the relationship between the expressions of CXCR3 and PD -1 on T lymphocytes and the pathological characteristics of CRC using t test . Results: Expression of CXCR3 on tumor -infiltrating T lymphocytes was lower, whereas the expression of PD -1 was higher than that on para -cancerous tissues and PB in patients with CRC. In patients with lymph node metastasis of CRC, the expressions levels of CXCR3 + PD -1 + on tumor -infiltrating CD8 + and CD4 + T lymphocytes were higher than those in patients without lymph node metastasis. The levels of CXCR3 + PD -1 + expressions differed depending on the primary tumor site. Conclusion: Expressions of CXCR3 and PD -1 on tumor -infiltrating T lymphocytes are related to the development of CRC and metastasis, providing clues for exploring the pathogenesis of CRC and developing new strategies for tumor immunotherapy.