Comprehensive Profiling of Immune Cell Populations and Cytokine Signatures in Colorectal Cancer Patients

Colorectal cancer (CRC) ranks as the fifth most prevalent malignancy in Vietnam. Cytological and molecular assays currently serve as crucial tools for assessing the immune status of patients. Here we document extensive alterations in both the cellular immune system in CRC patients using state of the art multi-color flow cytometry and its products (cytokines). We report a significant reduction in B and T lymphocyte populations in CRC patients, coupled with relatively stable NK cell and monocyte levels. These changes may be considered broadly characteristic of the disease. More specifically, several B cell subpopulations were increased in CRC patients, including B_CD21low, B_transitional and B_class-switched cells. Similarly, CRC patients displayed greater proportions T cell activation markers, including T_CD69+, T_CD8+CD28- and T_CD8 effector and T_CD8 effector memory cells. Leukocytes from CRC patients also exhibited an upregulation of NK cell receptors (CD25, CD57, CD69, KLRG1, p44) and enhanced cytotoxic capability of NK cells. Five out of 15 cytokines were significantly elevated in CRC patients. This study provides a comprehensive profile of cellular immune markers and cytokines that may serve as immune biomarkers and treatment response monitoring in CRC patients. These findings contribute to our understanding of the new and coordinated immunological landscape in CRC and will inform future diagnostic and therapeutic strategies.