To gain insight into the association of several Let-7 targets with tumorigenesis in vivo, we examined Hmga1, Hmga2, Arid3a, and Hif3a protein expression by immunostaining adenomas and adenocarcinomas, as well as adjacent normal tissue, from Lin28bLo/Let7IEC-KO mice. Here, HMGA1 is linked to adenocarcinoma.