PTTG1 and hepatocellular carcinoma: Then, these independent survival-associated DEGs were subjected to LASSO regression Cox analysis, and a 4-gene signature that can predict OS in HCC patients was developed: enhancer of zeste 2 polycomb repressive complex 2 (EZH2), feline leukemia virus subgroup C cellular receptor 1 (FLVCR1), pituitary tumor-transforming 1 (PTTG1), and thyroid hormone receptor interactor 13 (TRIP13) (Fig. 3A-B).