Sonic Hedgehog signaling, Ras/Raf/ mitogen-activated protein kinase (MAPK) signaling, the Notch pathway, phosphatidylinositol-3-kinase (PI3-K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) and TGF-β signaling are other pathways that are also involved in HCC development. The gene discussed is MTOR; the disease is hepatocellular carcinoma.