Can removing chemical groups from DNA make cancer worse? Elizabeth Tracey reports


Chemical groups called methyl groups can be removed from DNA by certain drugs used to treat cancer, but now a new study raises the possibility that in some people, such treatments unleash genes known to worsen cancer. William Nelson, director of the Kimmel Cancer Center at Johns Hopkins, explains.

Nelson: Some of the overmethylation is the way cancers stop genes that would otherwise be like the brakes on a car, so the cancer can just keep growing and growing. There are some drugs that interfere with the placing of these marks, so you reduce the number of methylation marks, hopefully unleashing the brake genes and you slow down cancer growth. This paper reports on two cohorts of patients who are treated with these kinds of drugs, and 30-40% of them it looks like there’s a gene that gets turned on at a higher level that might be generally dangerous.  :32

Nelson says careful genetic monitoring while treatment is underway may be the best strategy for detecting such an outcome. At Johns Hopkins, I’m Elizabeth Tracey.