CCNA2 and hepatocellular carcinoma: Waltonitone, an ursane-type pentacyclic triterpene extracted from Gentiana waltonii Burkill, recently appeared to exert an antitumor effect; waltonitone could suppress hepatocellular carcinoma cell proliferation and tumorigenesis via miR-22-regulated CCNA2 repression and partially via farnesoid X receptor modulation (47).