CD8A and neoplasm: High concentrations of CX3CL1 exist in the immune microenvironment of early colorectal cancer, which recruits NK cells, monocytes, and activated T cells to the tumor region; monocytes differentiate into macrophages and DCs for antigen presentation; activated T cells secrete IFN-γ, upregulating the expression of CXCR3 ligands to recruit Th1 and NK cells, promoting the activation of CD8+T cells and its killing effect on tumor cells.