However, TNBC cells with low ICAM1 expression co-culturing with CD8 T cells to study the alteration of ICAM1 expression in the tumor microenvironment of TNBC patients, the expression levels of PD-1 as well as CTLA4 were substantially elevated, and the levels of IFN gamma, TNF-α, and granzyme were significantly decreased (Figures 14E, F). Here, PDCD1 is linked to neoplasm.