Furthermore, high expression of HDAC2 and HDAC3 was positively correlated with lymph node metastasis (χ2 =15.474; 9.757) (P<0.001, P=0.002), TNM stage (χ2 =13.021; 7.693) (P<0.001, P=0.006), and differentiation (χ2 =9.125; 8.313) (P=0.003; P=0.004) in CCA; however, no such correlations were observed for HDAC8 (P>0.05; Table 1). The gene discussed is HDAC2; the disease is cholangiocarcinoma.