Characterization of Lymphocyte Subsets in Peripheral Blood of Patients with Colorectal Cancer

Abstract Purpose: Cellular immune response to cancer is known to be of great importance for tumor control. Until now, the role of systemic immune profiles in tumor progression remains unclear. Methods: By using multiparameter flow cytometry, the subset distribution and immunophenotype of lymphocyte subsets were investigated in peripheral blood mononuclear cell samples from 118 colorectal cancer (CRC) patients and 80 healthy donors. Results: Compared with the normal group, the numbers of T lymphocytes and Th lymphocytes were significantly decreased in the CRC group, whereas the number of NK cells was significantly increased. There was no significance between the two groups in the numbers of Ts, γδT, CD3+CD4+CD8+, and CD4+/CD8+ lymphocytes. The number of T lymphocytes was significantly increased after surgical resection, however, the number of B lymphocytes was significantly decreased. There was no significance in the number of other lymphocyte subsets neither before nor after rection. The number of NK cells increased in stage III-IV, as compared to stage I-II. The numbers of Ts and CD4+/CD8+ lymphocytes showed a correlation with the tumor differentiation degree. The number of T lymphocytes was higher in conditions that were without lymph node invasion and distant metastasis. The number of CD4+/CD8+ lymphocytes was significantly higher in the condition without perineural invasion. Conclusion: The altered phenotype of circulating immune cell subsets in CRC and its association with clinical outcome highlights the potential use of lymphocyte subsets as prognostic biomarkers in CRC, thereby contributing to better insight into the role of systemic immune profiles in tumor progression.