Intriguingly, we found that HDAC5 expression was higher in CD13+ compared to CD13− HCC cells by FACS (Figure 5D) despite that mRNA level of HDAC5 was comparable between these two cell populations (Figure 5E), suggesting the enhanced HDAC5 expression may mainly due to post‐transcriptional modification process caused by CD13. This evidence concerns the gene ANPEP and hepatocellular carcinoma.