Tracking Cancer’s DNA: Brain Tumors
With the help of a National Institutes of Health study and patients at the UC Brain Tumor Center and Mayfield Clinic, Christopher McPherson is mapping brain cancer genomes—a visionary project that could lead to improved treatments for future generations.
As a neurosurgeon, I treat disorders of the brain, spine, and nerves that typically require surgery. There are 200,000 new brain tumors estimated to be diagnosed in 2012 nationwide—60,000 of those will be what we call primary brain tumors, which are those that start in the brain like gliomas, and the majority of those will be glioblastoma, which is the malignant form. So it’s more common than people think. We would say in some ways the gliomas are very smart cancers—they evade the immune system. They grow very fast, so they also mutate very fast; even though one therapy may work for a while, the gliomas develop resistance and change very quickly.
The Cancer Genome Atlas (TCGA) is a National Institutes of Health–funded study. The goal is to map the genome of certain select tumors, [including] glioblastoma [and] other forms of glioma. Mapping the genome means mapping out every code—the entire sequence of the genome for a tumor—and basically looking for errors, mutations, or changes that are different from normal DNA so that we potentially have targets for treatment and better understanding of what causes them. [To do this] we provide tumor tissue from surgery, which is sent to the NIH. They map the genes from the tumor, and researchers can use that information to develop new treatments from there. We’re in our third year. This is an ongoing study that takes many years.
The holy grail is to find a very specific target that we can attack—a change in a receptor or a change in a protein—that’s different in a glioma cell from a normal cell. Then we can come up with a drug or vaccine or some new therapy that will target just that cell. There is always the possibility that [the patients participating in this study] could see new vaccines and new trials, [but] it’s really more paying it forward for future generations.
Ken Jacques is an engineer who works for the Federal Aviation Administration. He was diagnosed with a glioma in the left side of his brain near very important structures that controlled his speech and movement. We did surgery and removed the tumor. He was awake—we were able to use an MRI to map out the functional areas of the brain so we could remove the tumor and protect his functional areas. He was home in two days, [then] completed radiation and therapy. He’s doing very well. He sent his tumor into this TCGA study, so his story is one of hope. Obviously, the hope is that the things we find with TCGA will help us find treatments that can benefit him [and others] for the future.
My goal is to make this center here as good as any other center in the country so that people can stay with their family and be close to home [during cancer treatments]. I’m blessed to be able to do it.