Linking metabolism and epigenetic regulation in development of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the fifth most common form of cancer globally and is rarely curable once detected. The 5-year survival rate of patients diagnosed with late-stage HCC may be as low as 27%. HCC is a cancer largely driven by epigenetic changes that arise from exposure to exogenous environmental factors rather than coding sequence mutations. The liver is susceptible to effects from Hepatitis C and Hepatitis B viruses, exposure to aflatoxin and continuous excessive consumption of alcohol. The liver is a highly metabolic organ balancing many vital biochemical processes; exposure to any of the above environmental factors is associated with loss of liver function and is a major risk factor for the development of HCC. Emerging studies aim to examine the underlying metabolic processes that are abrogated in cancer and lead to the altered flux and availability of key metabolites important for epigenetic processes. Metabolites have been shown to act as substrates for many canonical epigenetic regulators. These enzymes are responsible for regulating histone modification, DNA methylation and micro RNA expression. By studying the impact of altered liver metabolism, we may better understand the long-term epigenetic processes, which lead to the development and progression of HCC.