Phenotype detection and analysis of NK cells in subcutaneous tumor-bearing mice with colon cancer

CHEN Ziyan; GUO Zichan; CHEN Lihua

doi:10.13276/j.issn.2097-1656.2025.07.013

Abstract：Objective To systematically detect and analyze the phenotypic characteristics and functional alterations of natural killer(NK)cells in subcutaneous tumor-bearing mice with colon cancer,with a focus on exploring the correlation between the expression levels of CD226 and TIGIT on NK cells.Methods Ten C57BL/6 mice were randomly divided into the subcutaneous tumor-bearing group of colon cancer(MC38 group)and the control group(WT group).The MC38 group was injected with MC38 cells,and the WT group was injected with sterile phosphate buffered saline.After modeling,flow cytometry was used to detect the overall proportion of NK cells,the proportion of each subgroup of NK cells,and the expression levels of cytotoxic molecules(perforin,granzyme B,and TNF-α)in peripheral blood,spleen,lungs,and liver.Furthermore,the expression levels of CD226 and TIGIT on NK cells were detected,and their correlation was further analyzed.Results Compared with the WT group,the MC38 group exhibited significantly reduced NK cell proportions in peripheral blood,spleen,lungs,and liver(P＜0.05),accompanied by a decrease in the proportion of cytotoxic NK cells(P＜0.01)and downregulated expression of cytotoxic molecules(performn,granzyme B,and TNF-α)(P＜0.05).Furthermore,NK cells in the MC38 group showed reduced CD226 expression(P＜0.01)and increased TIGIT expression(P＜0.01),with a negative correlation observed between the two molecules(P＜0.05).Conclusion Subcutaneous tumor-bearing mice with colon cancer exhibit altered NK cell phenotypes and impaired cytotoxic function.