Nevertheless, these PD-1+ CD8+ BC-infiltrating TILs, which are generally considered to be exhausted in the tumor microenvironment (TME), were found to retain some degree of polyfunctionality, such as cytokine production capacity and degranulation, when compared to those TILs infiltrating melanoma, thereby suggesting a differential regulation of these cells in BC13. Here, CD8A is linked to breast cancer.