MTOR and hepatocellular carcinoma: As mTOR cascade has been shown to be a key regulator of tumorigenesis, mTOR inhibitors have been developed and tested clinically in various tumor types, including HCC.46 It is important to note that the first generation of mTOR inhibitors, the Rapamycin homologs (Rapalogs), including Everolimus, are able only to partially inhibit mTOR.