Orthotopic hepatocellular carcinoma model with a controlled and reproducible tumorigenicity

To explore therapeutic strategies for hepatocellular carcinoma (HCC) there is a need for a suitable and reproducible animal model. However, most models produced thus far have drawbacks such as high rates of artificial tumor dissemination and complexity of the implantation technique. To circumvent these issues, we selected an appropriate HCC cell line coupled with a simple modality to prevent unintended tumor cell dissemination.

KDH-8 cells were inoculated into the rat liver. To prevent tumor cell leakage, a human fibrinogen/thrombin-coated collagen patch was attached on the site after withdrawal of the needle. In some animals, ligation of the hepatic artery was performed.

Early after injection, all rats (n = 60) developed a solitary nodule. Successful inoculation was observed in all animals with a leakage (dissemination) rate of 0%. Computed tomography (CT) demonstrated a well-demarcated low density mass accompanied with a central necrosis that mimicked a typical CT image of human HCC. Doppler ultrasonography demonstrated a vascularized property of the tumor. Tumor volumes increased with time, reaching 3299.5 +/- 290.0 mm3 at day 28 after inoculation. Thus the formed KDH-8 hepatoma was pathologically classified into a poorly differentiated HCC demarcated with surrounding connective tissue. After hepatic arterial ligation, tumor growth was impeded with an inhibition of 59.1 and 70.4% (day 21 and 28, respectively).

The current orthotopic hepatoma model enables a controlled and reproducible tumorigenicity and displays properties and histopathology resembling human HCC. It may be a useful tool in the investigation of antiangiogenic and anticancer therapeutics.