As it has previously been reported that Navtemadlin does not affect mouse tumor cells, we set out to test whether this indeed is the case by generating p53−/− B16-F10 melanoma cells from the parent cell line p53+/+ B16-F10 using the CRISPR-Cas9 method (Supplementary Fig. S1A and S1B). Here, TP53 is linked to melanoma.