PRF1 and neoplasm: The PDO TILs activities were evaluated by treatment with anti-PD-1 or anti-PD-L1 in murine tumor organoids that showed a strong increase of CD8 TILs and T cell activation markers such as interferon-gamma (IFNγ), perforin-1 (PRF1), and granzyme B recapitulating the PD-1/PD-L1 immune checkpoint [183].