Taken together, we observed that the Mex3a promoter methylation levels, in the context of HBV-associated HCC, are strikingly lower than those of CHB patients and healthy controls, whereas Mex3a mRNA levels in the context of HBV-associated HCC are remarkably higher than in CHB patients and normal individuals. The gene discussed is MEX3A; the disease is hepatocellular carcinoma.