The Faculty of Medicine of the University of Hong Kong announced Friday its discovery of a Novel method of gene therapy for Colon Cancer.

Researchers of the faculty have packaged a mutant survivin gene into the adeno-associated virus (AAV) system, and tested the product in colon cancer. AAV-mediated survivin mutant was proved to inhibit tumor growth. The report has been published in the Feb.2005 Issue of Gastroenterology in America.

AAV vector is a gene delivery system, which can facilitate gene transfer to cancer cells with better safety, efficiency, consistency and sustainability than other available gene delivery system.

According to the researchers, survivin is a protein which inhibits the apoptosis of the cell. It exists in most of the common human cancers but not in normal adult differentiated tissues. Suppression of survivin function resulted in spontaneous apoptosis, enhancement of druginduced cell death, and inhibition of tumor growth in vitro and in vivo.

Colon cancer is one of the commonest cancers in the world. In Hong Kong, it is the second most common cancer after lung cancer. The incidence of colon cancer had increased from 2,900 in 1997 to over 3,300 new cases in 2001, representing an increase of around 13 percent.

Treatment for early diseases includes surgery and/or chemotherapy and radiotherapy. However, the results of chemotherapy and radiotherapy for advanced stage patients are usually not satisfactory. Therefore, new treatment is needed.