Stopping germs from ganging up on humansNovember 20, 2008Keeping germs from cooperating can delay the evolution of drug resistance more effectively than killing germs one by one with traditional drugs such as antibiotics, according to new research from The University of Arizona in Tucson. John W. Pepper proposes a new strategy in the arms race between humans and germs-- targeting the teamwork within gangs of germs. Most drugs used to fight infections kill the vulnerable disease-causing organisms, or pathogens, but the resistant ones survive. The next generation will all carry the resistance to the drug.
"We know that the pathogen is causing the disease. The obvious solution is to kill the pathogen. It makes perfect sense, and that's what we've always done," said Pepper, a UA assistant professor of ecology and evolutionary biology. "But there's one big flaw with that -- and that is the evolution of resistance." Pepper's mathematical models show it takes longer for a group of cells to develop resistance to drugs that attack the teamwork factors than for individual cells to become resistant to a traditional antibiotic. He advocates developing drugs that attack the pathogens' methods and resources for cooperation. Pepper said once the teamwork is disrupted, the immune system can combat any remaining infection. He said this new approach will work against "old enemies and some new ones" that are becoming drug resistant, including methicillin-resistant Staphylococcus aureus bacteria (MRSA), HIV, malaria, tuberculosis, avian influenza and cancer. Pepper is also a member of UA's BIO5 Institute and an external professor at the Sante Fe Institute in New Mexico. His paper, "Defeating Pathogen Drug Resistance: Guidance from Evolutionary Theory," is scheduled for publication in the December issue of the journal Evolution. Pepper began investigating cooperation by studying parrots and dolphins. Now he studies cooperation among individual cells. Most cells such as a bacterium produce materials that ensure their own survival and maintain infections by helping both themselves and their fellows. For pathogens, there's strength in numbers. As they form groups, they become a greater threat. For example, MRSA produce more than 50 resources essential for the group. Where others may see an unconquerable defense, Pepper sees 50 opportunities. The number and type of materials produced within a gang of pathogens varies. However, if one material is eliminated, none of the cells will survive. Neither will the infection. He is currently collaborating with cancer biologists to attack chemicals that allow cancer cells to gang up on normal cells. One type of chemical, the angiogenesis factor, is secreted by cancerous cells to stimulate the growth of blood vessels into tumors. Blood vessels carry oxygen and nutrients to the cells in the tumor. Some doctors currently use angiogenesis blockers, such as the anti-cancer drug Avastin, to inhibit the signal. Without blood vessels, tumors suffocate and starve. As opposed to toxic drugs that poison and kill cancer cells, Pepper said these new types of anti-cancer drugs will stay potent longer. "The basic point I'm making is in order to save the patient, we don't have to have a drug that kills the cancer cells," Pepper said. If drug development continues to focus on killing individual cells, he said, "We're always going to keep running on the same treadmill. "We're going to be in this situation where we desperately need a new antibiotic by tomorrow, or maybe by yesterday," Pepper said. "That's not going to be a temporary emergency -- it's going to be a permanent emergency, unless we take a new approach." University of Arizona Science News and Science Current Events Tag Cloud This tag cloud is a visual representation of term frequencies of random science news topics with common terms grouped together and emphasized by their display size. Gamma Ray Color Vision Ozone Hole Salmonella Air Pollution Brown Dwarf Maize Iron Extrasolar Planets Visual Cortex Cognitive Decline Liver Cancer Anxiety disorder Child Abuse Uterine Fibroids Suicide Fatty Acids Myosin Neck Cancer Antarctic Stomach Cancer Antibiotics Asteroids Colon Cancer Snoring
See More: Science News Tags | |||||||||||||||||||||
|
Related Cancer Cells Current Events and Cancer Cells News Articles Newly appreciated membrane estrogen receptor important therapeutic target for breast cancer New research at Rhode Island Hospital has uncovered the biological effects of a novel membrane estrogen receptor, a finding that has potential implications for hormonal therapy for breast cancer. Researchers testing virus-gene therapy combination against melanoma Researchers at the Moores UCSD Cancer Center are injecting a modified herpes virus into melanoma tumors, hoping to kill the cancer cells while also bolstering the body's immune defenses against the disease. Predicting the return of prostate cancer: New Johns Hopkins study betters the odds of success Cancer experts at Johns Hopkins say a study tracking 774 prostate cancer patients for a median of eight years has shown that a three-way combination of measurements has the best chance yet of predicting disease metastasis. Study shows PET can measure effectiveness of novel breast cancer treatment A new study published in the July issue of The Journal of Nuclear Medicine shows that positron emission tomography (PET) scans in mice can be used to determine whether a novel type of breast cancer treatment is working as intended. Novel epigenetic markers of melanoma may herald new treatments for patients Melanoma is the most serious form of skin cancer, diagnosed in more than 50,000 new patients in the United States annually. While the rate of incidences continues to rise, survival rate has not improved and the race is on to find the genetic and cellular changes driving melanoma and to devise new means of detection and treatment. Insulin analogue glargine possibly increases cancer risk The risk of cancer possibly increases if patients with diabetes use the long-acting insulin analogue glargine instead of human insulin. Researchers pinpoint a new enemy for tumor-suppressor p53 Researchers at The University of Texas M. D. Anderson Cancer Center have identified a protein that marks the tumor suppressor p53 for destruction, providing a potential new avenue for restoring p53 in cancer cells. Effective pain treatment for cancer patients? Cancer patients often suffer from severe pain that cannot be effectively treated with conventional medication. Like burrs on your clothes, molecule-size capsules can deliver drugs by sticking to targeted cells It is now possible to engineer tiny containers the size of a virus to deliver drugs and other materials with almost 100 percent efficiency to targeted cells in the bloodstream. Cancer researchers link DICER1 gene mutation to rare childhood cancer Research published today in Science Express from the journal Science demonstrates the first definitive link between mutations in the gene DICER1 and cancer. More Cancer Cells Current Events and Cancer Cells News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||