We also noted that in the Wurmbach liver dataset, the mRNA expression level of CDKN3 was associated with tumour grade, hepatitis virus infection status, and satellite and vascular invasion (Fig. 4), but CYP2C9 and LCAT were not associated with tumour development (Additional file 3: Fig. S1 and Additional file 4: Fig. S2). These results suggest that CDKN3 may be a key gene in the transformation of liver cirrhosis to liver cancer, and is closely related to the occurrence and development of HCC. The gene discussed is CYP2C9; the disease is liver cancer.