Genetic variant responsible for resistance to cancer drugs in some patients of East Asian descent

A research team led by scientists at Duke-NUS Graduate Medical School in Singapore have identified a genetic variation that causes some patients to not respond to successful cancer drugs. Tyrosine kinase inhibitor drugs (TKI) are effective in fighting certain blood cell cancers, such as chronic myelogenous leukemia, in most patients. Now researchers have discovered that a common variation in the BIM gene in people of East Asian descent contributes to the ineffectiveness in some patients. "Because we could determine in cells how the BIM gene variant caused TKI resistance, we were able to devise a strategy to overcome it," said S. Tiong Ong, senior author of the study. Ong says that a class of drugs called BH3-mimetics, when added to TKI therapy, could override the resistance of cells with the BIM gene variant. The variant occurs in about 15 percent of the East Asian population, while no people of European or African ancestry were found to have this gene variant.