CD274 and neoplasm: Tumor infiltrating lymphocytes (TIL) collected from the tumor microenvironment of mice that received combination therapy had an increase in the percentage of interferon (IFN)‐gamma‐producing CD8+ T cells compared with single‐agent therapy, indicating a synergistic effect on anti‐tumor immunity.32 A possible mechanism for this synergy is that vaccination induces some anti‐tumor immunity that is overcome by upregulation of PD‐L1 on tumors.