Recent studies suggest that CD80 expression is upregulated in human colonic epithelial cells isolated from preneoplastic adenomas (Marchiori et al., 2019; Scarpa et al., 2015), while in skin SCC, a population of Cancer Stem Cells (CSCs) that express CD80 have been reported in both murine and human tumors (Miao et al., 2019). This evidence concerns the gene CD80 and cancer.