Gene mutation found

Scientists discover why some cancer drugs become less effective

SCIENTISTS here have found a mutation in a gene that makes some cancer drugs less effective, as well as a solution to tackle this problem.

This mutation appears in about 15% of East Asians, and to a lesser extent in other Asians, but is completely absent in Caucasians and Africans.

A team of 55 researchers, led by Assoc Prof Ong Sin Tiong of Duke-NUS Graduate Medical School, found that “targeted” drugs to combat specific types of lung and blood cancers did not work as well in patients with the mutated gene.

However, the shortcoming can be addressed by the addition of another drug that is currently not commercially available, but is used in clinical

It’s very rare that a laboratory-based discovery has the potential to change the practice of medicine in the year that it is discovered. — PROF PATRICK CASEY

trials elsewhere.

The existing targeted drugs, which block the growth and spread of the cancer by interfering with the molecules that cause the tumour to grow, are not cheap.

The bill can come up to S$2,000 (RM4,800) to S$3,000 (RM7,200) a month for lung cancer patients, with the drug able to extend life by as much as 30 months.

For leukaemia, the cost is S$4,000 (RM9,600) to S$5,000 (RM12,000) a month, with patients living a goodquality life for as long as a decade.

However, in about 20% of patients with these forms of cancers, the drug benefit is not as good as it is for the rest.

The team’s findings have been published in Nature Medicine – considered one of the the world’s top biomedical journals.

Prof Patrick Casey, senior vice-dean for research at DUKE-NUS Graduate Medical School, called the discovery “spectacular”.

He said: “It’s very rare that a laboratory-based discovery has the potential to change the practice of medicine in the year that it is discovered.”

This is because the science to discover the mutation, plus the drug to deal with that, already exists.

But before this discovery goes into clinical use, full-scale human trials are needed. The scientists hope to link up with a large pharmaceutical firm for funding.

The team came not only from DUKE-NUS but also from Genome Institute of Singapore (GIS) and several hospitals here and in Japan. It was the GIS that identified the slight mutation in the gene. — The Straits Times / Asia News Network