Researchers use light to battle cancer
By Ben Gruber BOSTON (Reuters) - In an intriguing approach to the fight against cancer, researchers for the first time have used light to prevent and reverse tumors using a technique called optogenetics to manipulate electrical signaling in cells. Scientists at Tufts University performed optogenetics experiments on frogs, often used in basic research into cancer because of the biological similarities in their tumors to those in mammals, to test whether this method already used in brain and nervous system research could be applied to cancer. "We call this whole research program cracking the bioelectric code," said biologist Michael Levin, who heads the Tufts Center for Regenerative and Developmental Biology. Whether optogenetics can be used to treat cancer in people remains unclear, but the underlying science of how electricity functions in the body could lead to new ways for treating a variety of diseases, the researchers said. "The idea is much like the brain, when neuroscientists try to figure out the semantics of electrical states in the brain. We try to figure out how patterns are encoded in electrical states in the body," Levin said. The researchers injected frog embryos with two types of genes, one to predispose them to cancer and another to produce light-sensitive ion channels in tumor cells. Ion channels are passageways in and out of a cell that open in response to certain signals. When the channels are open, the movement of ions in or out of the cell creates an electrical signal. The researchers activated the ion channels on tumor cells by exposing the embryos to light. By activating the channels and adjusting the electrical signals in the cells, the researchers said they were able to prevent and reverse tumor formation in 30 percent of the embryos. "You can turn on the light, in this case it's blue light, and you blink this blue light at this tumor, I believe it's 24 hours, and the tumor goes away," said Tufts biologist Dany Adams, another of the researchers. By targeting the electrical patterns in cells, it becomes possible to control how quickly the cells divide and what information they share with their neighbors, Levin said. "The electrical communication amongst cells is really important for tumor suppression," Levin said. "The bigger picture is to understand how these voltages are passed among cells and how they control the transfer of chemical signals among cells." The researchers said they are planning similar experiments on mammals. The study was published last month in the journal Oncotarget. (Reporting by Ben Gruber; Editing by Will Dunham)
