Over the past several years, the success of genome-wide association studies (GWAS) and pharmacogenomics has gradually begun to enable personalized medicine in some fields. In the field of liver diseases, host genetic factors are now very useful in clinical practice for predicting treatment outcome and adverse reactions for pegylated interferon plus ribavirin combination therapy against chronic hepatitis C virus (HCV) infection. Recently, three virus-related hepatocellular carcinoma (HCC) GWAS were reported from Asia. One study examined hepatitis B virus-related HCC in China, where hepatitis B is very prevalent, and the other two examined HCV-related HCC in Japan. We identified a common variant in the DEPDC5 locus associated with HCV-related HCC, and another group identified an association involving the MICA locus. In this review, we compare the results of these GWAS and earlier candidate gene studies. Further research is needed to determine the role of these single nucleotide polymorphisms on HCC risk, but identification of these markers could make it possible to assess the magnitude of the risk of cancer based on each patient's genetic background. Consideration of the genetic background of the patients will likely play a role in personalized medicine for HCC, and understanding the mechanism underlying the association could suggest novel promising therapeutic targets in the future. (Cancer Sci 2012; 103: 846-850) O ver the last several years, the success of GWAS and the International HapMap Project, a large-scale database of SNPs, has identified genetic risk factors for more than 150 diseases, as well as genetic differences in drug response.(1-4) The success of these studies as well as pharmacogenomics has gradually begun to enable personalized medicine in some fields. (5)(6)(7)(8) The goal of personalized medicine is to optimize the medical care and outcomes for each patient based on clinical, genetic, and environmental information.(9) In the field of liver diseases, host genetic factors are now very useful in clinical practice for predicting treatment outcome and adverse reactions of PEG-IFN-a plus ribavirin combination therapy against chronic HCV infection, (10)(11)(12)(13)(14)(15)(16)(17) which causes chronic hepatitis and HCC.
Epidemiology and Risk Factors of HCCHepatocellular carcinoma is the third leading cancer-related cause of death and the seventh most common form of cancer worldwide. (18) There are 750 000 new cases of HCC and nearly 700 000 deaths each year, making it a lethal form of cancer. (18) A variety of risk factors for HCC have been reported, including hepatitis viruses, vinyl chloride, tobacco, aflatoxin B1, alcohol consumption, non-alcoholic fatty liver disease, diabetes mellitus, obesity, diet, coffee, oral contraceptives, and hemochromatosis.(19) Incidence of HCC varies around the world, largely reflecting the distribution of HBV and HCV. As HBV infection is highly prevalent in many Asian countries and in Africa, HBV is the most common etiology of HCC in these regions, whereas in many ...