Mutation Patterns and Genotypes Associated with Hepatocellular Carcinoma in HBV/HCV Coinfected Patients

Due to common routes of transmission, some patients are coinfected with both hepatitis B virus (HBV) and hepatitis C virus (HCV).

As reported in the September 2006 Journal of Viral Hepatitis, Italian researchers conducted a study of virological factors associated with hepatocellular carcinoma (HCC, a form of liver cancer) in this population.

The study included 38 consecutive patients with HCC; 18 were HBV/HCV coinfected and 20 were infected with HBV alone. In addition, 23 HBV/HCV coinfected patients without HCC were enrolled as a control group.

Viral replication was evaluated by detecting and quantifying HBV and HCV genomes. The HBV precore/core region, encompassing the pregenome encapsidation signal involved in viral replication, was analyzed by direct sequencing.

Results

HBV viral load was significantly lower in HCC patients with HBV/HCV coinfection compared to those with HBV alone (P = 0.04)

2 different HBV viremia profiles were detected in coinfected patients with and without circulating HCV.

HBV genotype D was prevalent in all 3 groups.

HCV genotype 1b was the most common strain among all HCV positive patients.

Lower variability in the precore/core region was found in HBV/HCV coinfected patients compared with HBV monoinfected individuals (P = 0.0004).

A synonymous T1936C mutation was found in all HCC cases in HBV/HCV coinfected patients not related to the presence or absence of circulating HCV.

A hyper-mutated precore strain, characterized by the same mutational pattern, was identified in three HCC cases.

Conclusion

The researchers concluded that, "The mutational pattern of the precore/core region was closely related to HBV replication efficiency, and specific HBV mutations selectively associated with HCV coinfection could be linked with accelerated HBV/HCV-related disease progression."

09/01/06

Reference
M S De Mitri, R Cassini, G Morsica, and others. Virological analysis, genotypes and mutational patterns of the HBV precore/core gene in HBV/HCV-related hepatocellular carcinoma. Journal of Viral Hepatitis. 13(9): 574-581. September 2006.