CCNE1 and hepatocellular carcinoma: In an independent cohort of 371 HCC samples from the Cancer Genome Atlas (TCGA) database, PCK1 expression was positively correlated with p27Kip1 expression (r = 0.3158, P < 0.0001; Fig. 7a) and negatively correlated with CCNE1 expression (r = 0.3692, P < 0.0001; Fig. 7b).