The altered metabolism of cancer cells allows them to grow rapidly and proliferate, leading to the development of aggressive tumors often able to spread, or metastasize, to other areas of the body. But when subjected to stressful conditions, such as oxygen- and nutrient-deprivation in the center of a tumor or an onslaught of chemotherapeutic agents, these cells are able to stop proliferating and cannibalize portions of themselves, a process known as autophagy.
"This ingenious property allows these cancer cells to tolerate enormous amounts of stress," said White, who also is a professor of molecular biology and biochemistry at Rutgers University. "If they're starving or stressed, they eat themselves and hunker down until the stress is removed. Then, as soon as the stress is gone, they grow back, often killing the patient. If we can understand this process and exploit it for cancer therapy, we may develop new ways to kill the cancer cells without killing the normal cells."
Autophagy is believed to confer stress resistance to cells by providing energy and disposing of old or damaged cell parts that might otherwise prove harmful to the cell over time, and it is not unique to cancer cells: Coller studies a metabolic state known as cellular quiescence in fibroblast cells. Fibroblasts are found in connective tissue, which includes cartilage and the cellular matrix known as stroma that provides support to body structures, such as organs, glands and also tumors. Akin to dormant cancer cells, quiescent fibroblasts take a break from the normal cell growth cycle, but maintain the ability to re-enter the cycle in the future. Like dormant cancer cells, quiescent fibroblasts often engage in autophagy.
Cancer researchers now recognize that a full understanding of how a tumor behaves in response to stress req
|Contact: Kitta MacPherson|