To corroborate these findings and ensure this difference in PD-L1 expression was not an effect of siRNA transfection, CRISPR-Cas9 was utilised to knockout (KO) MLH1 and MSH6 in the murine CRC cell line CT26 (Figure S3) and in U2OS cells (Fig. 2A). The gene discussed is CD274; the disease is colorectal carcinoma.