Hepatocarcinoma: genetic and epigenetic features.

HCC is the third leading cause of cancer-related deaths worldwide, accounting for about 1 million deaths annually. The incidence of HCC is highest in Asia and Africa, where the endemic high prevalence of hepatitis B and hepatitis C strongly predisposes to the development of chronic liver disease and subsequent development of HCC. Patients with HCC generally present at an advanced stage due to compensated cirrhosis defined by the absence of pathognomonic symptoms, resulting in death within 6 to 20 months, suggesting an urgent need in treatment modalities that will dramatically decrease the mortality rate of HCC. The molecular hepatocarcinogenesis is, however, a gradual process during which genetic alterations progressively accumulate and lead to HCC through intermediate preneoplastic stages. With the advent of whole genome sequencing tools, various mutations associated with HCC have been identified, which have advanced our molecular understanding of HCC. However, the frequency of these mutations is rare, and these genetic mutations only partly explain the etiology of the disease. Better understanding and characterization of novel genetic and epigenetic alterations, which are important to hepatocarcinogenesis, may help understand the molecular pathogenesis of HCC, as well as providing novel therapeutic targets for HCC treatment. Further consideration should be given to developing more effective molecular diagnostic markers and targeted drug therapy.