Most people think of cancer as a disease of disorderly DNA. Changes, or mutations, in the sequence of DNA alter the function of the proteins made from that DNA, leading to uncontrolled cell division.
But between DNA and proteins is another layer of information, called messenger RNA (mRNA), which serves as a crucial link between the two. New research suggests that mRNA itself may carry cancer-causing changes. And, because genetic tests don’t usually look at mRNA, those changes have so far gone undetected by cancer doctors.
“If you sequenced the DNA in cancer cells, you would not see these changes at all,” says Christine Mayr, a molecular biologist at the Sloan Kettering Institute who is the senior author of a new paper on the topic published today in Nature. “But these mRNA changes have the same ultimate effect as known cancer drivers in DNA, so we believe they may play a very important role.”