Considering that IFNγ secreted by T cells has been demonstrated to be a profound modifier of the tumor microenvironment17,18 and one of the key and strongest inducers of PD-L1 (ref. 19), we used whole-genome CRISPR–Cas9 gene knockout screens to identify the regulators of PD-L1 expression in tumor cells after IFNγ exposure in an unbiased manner. This evidence concerns the gene IFNG and neoplasm.