TGFB1 and hepatocellular carcinoma: In regard to SMAD7, which is a negative feedback regulator for the TGFβ pathway, although its expression was not affected by decitabine in SNU449 cells, we observed that its promoter was hypomethylated (i.e., signaling a possible higher expression/activity) in early stage human HCC, especially in poor-prognosis tumors associated with tumor recurrence.