TGFB1 and neoplasm: In agreement with the above findings, we also found that the expression of the PrPC target genes App, Bace1, Dkk3, Pdgfc and Tgfb1 were all increased in the tumor versus normal tissue of both types of mice, and that the tumor levels were higher in homozygous versus heterozygous mice (Fig. 4B–F).