To investigate whether IL-24 is required for the tumor protective effect of calcipotriol-plus–5-FU immunotherapy, we compared mutant p53 clone development in WT and Il24–/– (Il24KO) mice on the C57BL/6 background, which received control, 5-FU, calcipotriol, or calcipotriol-plus–5-FU treatment (Figure 6B). Here, IL24 is linked to neoplasm.