A variety of key signaling pathways contribute to HCC tumorigenesis including the MEK/ERK (2), mitogen-activated protein kinases (MAPK) (3), mammalian target of rapamycin (mTOR) (4), JAK/STAT (5), Hedgehog (6), and TGF-β signaling pathways (7). The gene discussed is MTOR; the disease is hepatocellular carcinoma.