HCV tumor promoting effect is dependent on host genetic background.

Area of Science:

• Hepatology
• Oncology
• Virology

Background:

• Hepatocellular carcinoma (HCC) is a major risk for Hepatitis C virus (HCV) infection.
• HCV transgenic mice do not develop HCC due to a lack of immune response.
• Chronic HCV infection causes inflammation, unlike in HCV transgenic mice.

Purpose of the Study:

• To investigate the role of HCV proteins in HCC development.
• To examine the effect of HCV on inflammation-associated hepatocarcinogenesis in vivo.
• To determine the influence of host genetic background on HCV-driven HCC.

Main Methods:

• HCV transgenic mice were crossed with Mdr2-knockout mice to create Mdr2-KO/HCV-Tg mice.
• Tumor incidence, hepatocyte mitosis, and apoptosis were analyzed.
• Gene expression and protein analyses were performed to identify contributing factors.

Main Results:

• Mdr2-KO/HCV-Tg females (N2 generation) showed significantly larger tumors and enhanced inflammatory gene expression compared to Mdr2-KO mice.
• In the N7 generation, no difference in tumor development was observed between Mdr2-KO/HCV-Tg and Mdr2-KO mice.
• HCV transgene expression was consistent in both generations.

Conclusions:

• The HCV transgene accelerated inflammation-associated hepatocarcinogenesis.
• This acceleration was dependent on the host genetic background.
• Genetic factors play a crucial role in modulating the oncogenic potential of HCV proteins.