| Some animals apparently can resist
cancer by strengthening their immune system in preparation for winter, Johns
Hopkins researchers said on Wednesday. The scientists said their study is the first to show that the central nervous system, reacting to environmental changes, may spark changes in the body's immune system that control the growth of tumors. They said if that is the ease, a better understanding of how the process works eventually could lead to new cancer treatments. Dr. Randy Nelson, an associate professor of psychology at Hopkins, stressed at a meeting of the Society of Neuroscience that further study would be needed to confirm a connection between the length of the day, the animals' immune system and cancer. More work also would be needed to show that the findings could be applied to human cancer. Dr. Faye Austin, an immunologist with the National Cancer Institute in Bethesda, said: "It's a very intriguing observation that the length of exposure to light can affect the growth of a tumour. But I think that the draws really need further work to clarify the mechanics." But Austin said the findings were surprising and important, only because they open up a new approach for research. Studies showed that stress weakened the immune system in animals. They figured that because winter is stressful, the season probably causes exertion (影响) on the immune system. The researchers reasoned that animals that compensated by boosting (促进) their immune systems as winter approached would have a better chance of surviving and producing offspring. "In the same way that animals have evolved to select the best time to breed, it struck me that animals ought to be able to predict when conditions would be challenging immunologically." Nelson said. |