Consistent with our previous report [27], TTF-1 positive lung adenocarcinomas developed in EGFRTL/CCSP-rtTA/Cebpb+/+mice (Fig. 5C; I and II) as well as in EGFRTL/CCSP-rtTA/Cebpb-/-mice (Fig. 5C; III and IV) when treated with doxycycline for 10 weeks. This evidence concerns the gene TTF1 and lung adenocarcinoma.