For example, bitransgenic MMTV-neu/MMTV-TGF-β1 mice exhibited higher levels of circulating tumor cells and lung metastasis than the MMTV-neu mice and the tumors from the bigenic mice had higher levels of vimentin as well as activated Smad2, Akt, and MAPK [103]. This evidence concerns the gene TGFB1 and neoplasm.