MKI67 and neoplasm: As compared to BRAFV600E/PTEN−/− tumours, YUMMER1.7 tumours had a significantly higher proportion of proliferative (Ki67+) tumour cells, which was slightly decreased upon resistance to αPD-1 treatment (Fig. 6G and 23.23% in IgG-treated samples versus 18.22% in αPD-1-relapsed samples).