SMAD3 and cancer: The target genes of these five differentially expressed miRNAs were especially and highly more enriched in the Transfac (TF) GO terms than any other category of GO terms (Figure 4, bottom plot), which included the critical GO terms of the proto-oncogene c-Jun and c-Fos motifs, as well as the cancer-associated Smad3 motifs (Table S8).