APOBEC3B and neoplasm: Transplantation of an EPA3B mouse tumor cell line into WT C57BL/6J or EPA3B C57BL/6J transgenic mice resulted in the growth of EGFRL858R+ A3B+ tumors in EPA3B C57BL6/J transgenic mice but not WT C57BL/6J mice (Extended Data Fig. 1j–m), suggesting a level of immune tolerance to both the EGFRL858R and A3B transgenes.