CD80 expressing cancer cells have been identified in human skin SCC (Miao et al., 2019) and pre-neoplastic colon lesions (Marchiori et al., 2019; Scarpa et al., 2015), and our analysis of human cancer cell line transcriptomics data further suggests that cancer cell CD80 expression is present in a broad range of solid epithelial cancers. This evidence concerns the gene CD80 and cancer.