MTOR and hepatocellular carcinoma: The major oncogenic molecular signaling pathways in HCC, including receptor tyrosine kinases (RTKs), RAS/RAF/MEK/extracellular‐signal‐regulated kinase(ERK), phosphoinositide 3‐kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR), Wnt/β‐catenin, janus‐kinase (JAK)/signal transducer activator of transcription (STAT), Hedgehog (Hh), Hippo pathway (12).