Liver cancer research has been constrained by the lack of ideal animal models for verification. The large and small mice commonly used in laboratories do not develop spontaneous chronic hepatitis, and liver cancer discovered on mice is a far cry from that discovered on human beings. The target of liver cancer treatment in this experiment was woodchucks, which, as a large rodent, could be said to be a fellow sufferer of human B hepatitis carriers. After the rodent was born, it would contract viral hepatitis vertically and become a carrier just like a human being, then grow liver cancer. In the world of nature such model of animal resemblance to human hepatitis and liver cancer is hard to find. Moreover, once the woodchucks are infected with liver cancer, they will soon die.
In recent years the NTU medical team was committed to the development of new methods for liver cancer treatment. In the areas of gene therapy, the team has come up with many possible recipes. By combining four different recipes, and having these recipes mixed like a cocktail, the team as able to discover an anti-cancer gene combination that was more effective and had less side effects. First, they used two angiogenesis suppressor gene (PEDF and endostatin) to inhibit new tumor blood vessels, starving liver cancer cells by blocking the blood supply to the tumors; then, the team members used two cytokine genes (interleukin-12 and GM-CSF) to induce the body to produce its own anti-cancer immunity, thereby killing the cancer cells.
Studies have confirmed that this cocktail mix method is more effective in treating multiple liver cancers than the use of any single ingredient. When applied to the woodchucks infected with chronic B hepatitis, it successfully shrunk the size of tumors inside the woodchucks, or even resulted in their total regression. In the meantime, the researchers found that the hepatitis viruses within the woodchucks weren’t activated because of this treatment, and the functions of their livers weren’t significantly affected.
Hepatitis, cirrhosis, and cancer can be said to comprise the trilogy of liver cancer, which is the most important type of cancer for Taiwanese nationals and the most common cause of death. NTU’s experiment proves that cocktail gene therapy has clinical feasibility and low side effects in the future, and thus reveals a silver lining for the battle against liver cancer. The achievements of the present research are patent pending worldwide.