Genetic Characteristics of Hepatitis B Associated with Risk of Liver Cancer
Different genetic characteristics of the hepatitis B virus (HBV) are associated with varying risks of developing hepatocellular carcinoma (HCC), the most common form of liver cancer. These results were recently published in the Journal of the National Cancer Institute.
The liver is the largest organ in the body and is responsible for over 500 functions. These include the secretion of glucose, proteins, vitamins, and fats; the production of bile; the processing of hemoglobin; and the detoxification of numerous substances. Hepatocellular carcinoma, the most common type of liver cancer, is named for the type of cell within the liver where the cancer originated.
The hepatitis B virus is a virus that causes inflammation of the liver. Unfortunately, an infection with HBV increases an individual’s chances of developing HCC, and it has been demonstrated that a greater amount of HBV in the blood (viral load) is associated with an increased risk of developing HCC. What has remained unclear, however, is how genetic variances within the virus itself may affect a patient’s risk of developing HCC.
Researchers from Taiwan recently conducted a study to evaluate potential genetic variances within the HBV virus and their possible effects on the risk of HCC. The study included blood samples from 2,762 Taiwanese (taken between 1991 and 1992) who were infected with HBV but had not developed HCC when the study began. Researchers found that specific genetic variances were associated with an increased risk of developing HCC, regardless of the viral load of HBV among individuals.
The researchers concluded that not only viral load of HBV but also identified genetic variances of HBV increase the risk of developing HCC.
Reference: Yang H-I, Yeh S-H, Chen P-J, et al. Associations between hepatitis B virus genotype and mutants and the risk of hepatocellular carcinoma*. Journal of the National Cancer Institute*. 2008; 100:1134-1143.