May 8, 2013 | by Nicole White
Not all brain cancers can be cured through surgery. Although a surgeon may be able to remove the main tumor mass, individual cells may have already spread to normal brain tissue, leading to relapse. Neural stem cells, which naturally migrate to cancer cells, could offer a powerful new treatment option.
In research published today in Science Translational Medicine, City of Hope's Karen Aboody, M.D., reported that neural stem cells appear to provide a safe and effective way to deliver cancer-killing drugs to gliomas, an especially dangerous and hard-to-treat form of tumor.
The study explains how neural stem cells were genetically modified to express therapeutic enzymes that, when injected into mice, homed in on cancer cells. These enzymes were then able to convert a prodrug – a benign form of a drug – into a potent cancer-killing drug that shrinks tumors. The prodrug itself, when given orally, was able to cross the blood-brain barrier, which blocks most chemotherapy drugs.
In the study, treatment with the neural stem cells resulted in significantly smaller tumors, about one-third the size of untreated tumors.
Residual tumors, however, were found to grow back over time, indicating that a single round of the treatment may not be enough to zap tumors completely. Further study will be necessary to determine the appropriate number of treatments and dosage of the prodrug.
The same research has since led to preclinical testing in a human trial at City of Hope. Meanwhile, Aboody and her team continue to study this promising platform for treatment, including its potential to treat other cancers and to deliver other cancer-killing compounds.
The Science Translational Medicine report offers an overview of a treatment option that seems only to be growing in potential.