IGF2 and neoplasm: Interestingly, we observed a shorter latency of tumor formation - 10.4 weeks (range: 7–25 weeks) but a similar incidence as 14 of 44 p16/p19−/−×BKE mice (32%) developed tumors in the left hindimb when injected with DF-1 cells expressing KrasG12D and Igf2.