MKI67 and neoplasm: Western blot analysis of tumor lysates showed that anti-mPD-1 treatment led to a reduction in F4/80, PD‐L1, Ki‐67, and PCNA levels, suggestive of reduced macrophage infiltration and tumor cell proliferation, although only the decrease in PCNA reached statistical significance (Fig. 2E and Supplementary Fig. 1B).