October / November 2008
A CURE AT WHAT PRICE? â€“ Searching for Personalised Yet Affordable Medicine
or five years, Prof Huynh The Hung from the Laboratory of Molecular Endocrinology in National Cancer Centre Singapore (NCCS) and his team have been working towards a noble dream.
Recently, NCCS joined hands with AstraZeneca, an Anglo-Swedish pharmaceutical firm, to test drugs to combat HCC. The combination of drugs being tested by the team is almost infinite. Apart from testing new compounds periodically provided by pharmaceutical companies, they may also combine the new compounds with existing drugs to see if better results can be attained. And even though Prof Huynh and his team now primarily deal with liver cancer, results of their work could potentially be used on other solid tumours.
They embarked on a journey to come up with a personalised and yet affordable medicine to treat cancer. While personalised medicine is not new, most researchers are focused on looking for a treatment or drug that works in treating cancer. What sets this project apart is that the cost of therapy for the patient, should the treatment require more than two or three drugs, is another key consideration. Hence, Prof Huynh has to strike a tough balance, which could possibly explain why researchers often ignore the question of cost. This project entails taking tissues from a tumour of, for example, a liver cancer patient for implantation into the liver of six to eight mice. These SCID mice, as they are known, are immuno-deficient and they are commonly used as hosts for normal and malignant tissue transplants. This process is known as surgical orthotopic implantation and is believed to be available only in NCCS for research on hepatocellular carcinoma (HCC). The tumours are then allowed to grow in the mice while the team maps out several treatments for them using a combination of not more than three different drugs. These drugs are then administered to the mice as they would be to the patients. The mice are then monitored to gauge the response of the different drugs or combinations of drugs using the CT and PET scans. In doing so, it gives the team an idea of the combination of drugs that would work best for the respective patients whose tissues were grown in the mice.
It was not smooth sailing for Prof Huynh when he first embarked on his research. In fact, it drew a lot of flak from the research community as tissues from patients were implanted and grown under the skin of the mice.
However, due to the underlying liver disease, not all patients are able to donate their tumour tissue for making xenografts and not all the HCC tissues from the patients will successfully grow in mice for drug testing. Furthermore, many patients may not have enough time to wait for the test results or be able to finance the surgical orthotopic implantation procedure or the drugs recommended. In these cases, Prof Huynh may still be able to find effective solutions by comparing the protein profile and/or gene signature of the affected patient with other patient-derived HCC xenografts in his therapeutic programme database to look for similarities and therapeutic regimens. Following this, he may also be able to recommend less expensive drugs that are likely as effective.
But his persistence has finally paid off. With the new technique of surgical orthotopic implantation, many pharmaceutical companies have been approaching him to do pre-clinical testing for their new drugs. Hopefully, in the near future, this will result in patients having access to drugs that are personalised yet affordable. By Carol Ang
A razorSHARK design. Salubris is a National Cancer Centre Singapore (NCCS) bi-monthly newsletter publication.