Cancer vaccine offers hope for ADVANCED colon cancer patients with limited TREATMENT options.
Thursday, 27 July 2006

27 July 2006 - Singapore’s first bench-to-bedside therapeutic cancer vaccine clinical trial led by the National Cancer Centre Singapore has shown encouraging results in advanced colon cancer patients. In a unique translational research project in partnership with a biotech company, NCCS and Danish teams of doctors and scientists have developed a high quality dendritic cell (DC) vaccine for the treatment of advanced colon cancer patients.

Achieving Tumour Control

In the study, patients are given 10 injections over 5 months, or once every fortnight. This vaccine is injected under the skin and found to be without any significant side effects in all 16 advanced colorectal cancer patients treated so far. To date the results have been encouraging with some of the patients’ tumours under control. Many of the 16 patients had received all conventional treatments before they entered the cancer vaccine clinical trial.

However, there is some way to go before this vaccine is available in the market. “What is good is that cancer cells can be attacked without harming normal cells,” said Dr Toh Han Chong, NCCS Principal Investigator and Senior Consultant. “We are selecting colorectal cancer patients with a specific protein on their cell surface, which the vaccine is meant to target.” The use of the vaccine hasn't been approved yet and the vaccines remain experimental, available now only through clinical trials.

Collaboration essential

Scientists and clinicians have worked together closely to perfect the art of producing these vaccines. “This is a delicate, labour intensive process, requiring a highly skilled multidisciplinary team,” said Dr Toh. Vaccine production begins by obtaining a blood sample from the patient. Translational research analysis by means of sophisticated technology available in Singapore and Denmark is also applied to monitor these cells and assess the vaccines for treatment benefit. “This is a true bench-to-bedside treatment project with patients, scientists and clinicians working together ‘under one roof!’ ” said Dr Toh.


Developing dendritic cell vaccines


Dendritic cells are very specialized white blood cells that help the immune system recognize and destroy antigens. They are considered to be the most powerful vehicle for cancer vaccine production. DCs are cultivated from the patient's blood and grown in the laboratory, where they are exposed to cancer cell antigens to be presented to the immune system’s T cells. When the DCs are reinjected into the patient, they recognize the antigens on the patient's cancer cells through the T cells. Sometimes specific genes are added to DCs to further stimulate the patient's immune system. Once in the patient’s body, the manipulated DC vaccine cells target the cancer cells, as well as recruit other cells like T cells in the immune system to join the fight.


Pushing Boundaries of Medicine


“Such novel cancer vaccine research has pushed the boundaries of medical knowledge to offer options even to advanced cancer patients. As a center of excellence for cancer care, we need to constantly invest in translational research, “ said Prof Soo Khee Chee, Director NCCS.

The researchers believe that in the next 12 months or so, it is likely that they will see some cancer vaccines being approved for clinical use by the bedside. Till then, the team is working to further improve the effectiveness of such treatment options.

About Colorectal Cancer


Colon Cancer is the commonest cancer in Singapore and one of the leading cancers worldwide. The majority of patients with colorectal cancer will develop advanced disease and the median survival time of these patients is between 6 and 9 months without treatment. For more information, please check http://www.nccs.com.sg.

For more details, photos and media interviews on the above, please click [here].