We found that 55% of mice receiving PTPN2‐deficient OT‐1 naive CD8+ T cells were tumour‐free at 55 days post‐adoptive transfer, whereas only 18% of mice receiving control OT‐1 naive CD8+ T cells were tumour‐free (Fig 2F) and this was accompanied by the increased presence of OT‐1 CD8+ TRMs in the skin (Fig 2G). This evidence concerns the gene PTPN2 and neoplasm.