PCNA and hepatocellular carcinoma: HMGB1 not only increased cyclin D1 and PCNA to induce the proliferation of HCC [47], but also regulates for tumor multiplicity and size, alpha-fetoprotein (AFP) level and advanced TNM stage in HCC [48], indicating HMGB1 could be used as a biomarker for HCC diagnosis which deserves further study [49].