Researchers at Johns Hopkins have identified the mechanism by which cancer spreads, identifying a protein that acts as a kind of signal to a tumor to start sending cells to colonize other places in the body.
For decades, scientists have tried to fight cancer as they have fought any other disease: by identifying the disease agents and finding the magic bullet that will kill or immobilize the agent. In cancer, however, recognition that a new approach will be required has been accepted by oncologists and scientists studying the disease. Cancer is a disease that is active at the genetic level, and may require treatment on that level. Currently, chemotherapy – essentially, treating the body by poisoning fast-reproducing cells – remains the treatment of choice, with the best results.
However, researchers continue to look at other options for treating cancer, and talk less about a magic bullet, and more about treatment protocols, combinations, and drug cocktails than ever before. Oncologists talk about “managing” rather than “curing” the disease.
Much of the cutting-edge research focuses on immunotherapy – using the body’s own immune system to fight the cancer. But another valuable weapon has just been added to the arsenal, as a young researcher at Johns Hopkins University has identified the precise mechanism by which cancer cells metastasize through the body.
Cancer itself is most dangerous in its metastasized form – when it has spread throughout the body. Typically, cancer begins as a primary tumour and in time, cells break off and travel through the body, finding a hospitable location elsewhere to plant themselves and start new tumors. Though some cancers can be fatal in themselves, many cancers in themselves, such as breast cancer, are not fatal if they remain self-contained. They become fatal when the tumors spread to vital organs such as the lung, where they interfere with breathing, or other critical organs.
Being able to slow or stop cancer metastasis would be a giant step in controlling the disease.
At Johns Hopkins, a young researcher named Hasini Jayatilaka observed, when still an undergraduate, that cells break off a primary tumor and begin colonizing when they become too densely packed – a behavior that mimicked the behavior of bacterial cells. Later, as a researcher at Johns Hopkins, Jayatilaka was able to pursue this line of inquiry, and confirm that cancer cells, like humans, do not want in a very densely populated area. When the density of cells in a tumor reaches a certain point, two proteins are released that signal that the tumour area had become too crowded, and thus it was time to send cells off to colonize other parts of the body. The proteins that send these signals are called Interleukin 6 and Interleukin 8, a family of proteins already under investigation for its ability to assist in fighting cancer at the molecular level.
“If you look at the human population, once we become too dense in an area, we move out to the suburbs or wherever, and we decide to set up shop there,” Jayatilaka said. “I think the cancer cells are doing the same thing.”