By Barbara Bronson Gray HealthDay Reporter MONDAY, June 11 (HealthDay News) — A widely prescribed drug,metformin, may lower the risk of invasive breast cancer inpostmenopausal women with diabetes, a new study indicates. The research, published online June 11 in the Journal of Clinical Oncology , echoes other recent studies that have suggested the diabetes drugmay help cut the chances of prostate, pancreatic, liver and oralcancer, as well as certain forms of melanoma. The researchers found that the incidence of invasive breast cancerwas 25 percent lower in women with diabetes who were takingmetformin than it was in women who weren't taking the drug. Approximately 25.8 million people in the United States havediabetes, according to the U.S. Centers for Disease Control andPrevention. Between 90 percent and 95 percent of these cases aretype 2 diabetes, in which the body's ability to make and useinsulin deteriorates. "Type 2 diabetes is a disease of insulin resistance,"said study co-author Dr. Rowan Chlebowski, a medical oncologistwith the Los Angeles Biomedical Research Institute at Harbor-UCLAMedical Center, in Torrance, Calif. Insulin is a hormone that helps regulate the level of glucose(sugar) in the body. With type 2 diabetes, the body manufactureslarger quantities of insulin to maintain normal levels of glucosein the blood. Metformin, commonly used to treat type 2 diabetes, increasesinsulin sensitivity and improves the control of blood sugar."It makes the insulin you have more effective,"Chlebowski explained. The drug, approved in the United Kingdom in1958 and in Canada in 1972, was introduced in the United States in1994. The new research looked at relationships among diabetes, metforminuse and breast cancer among over 68,000 women between 50 and 79years old in the national Women's Health Initiative project.In this group, 3,401 had diabetes and 3,273 invasive breast cancerswere diagnosed during the study. Because of the design of the Women's Health Initiativetrials, detailed information was available for this large anddiverse population in many areas, including breast cancer riskfactors, baseline mammograms, clinical breast exams andverification of breast cancers when they occurred. Researchers werealso able to know which participants had diabetes — alongwith their use of diabetes medication. The trials excluded women who had already had breast cancer. Womenwho had developed diabetes before adulthood (suggesting they weretype 1 diabetics) were also excluded from the study. How can a drug that treats people with high blood sugar play a rolein reducing breast cancer risk? Chlebowski suggested that metformin"may inhibit the master regulator of the cell,‘mTOR,' changing critical pathways involved incancer." The mTOR pathway is affected by a wide range of cellular signals,including growth factors, hormones such as insulin, nutrientsincluding glucose and amino acids, cellular energy levels andstress. A key cell pathway associated with mTOR is criticallyinvolved in cell reproduction and survival. Chlebowski and other experts cautioned against looking to metforminas a cancer prevention drug just yet. "It's too soon to change clinical practice," saidJennifer Ligibel, a medical oncologist in the Women's CancerProgram at the Dana-Farber Cancer Institute in Boston. "Whilea number of other studies have suggested metformin has a role inpreventing breast cancer and its recurrence, I would not recommendwomen take metformin for breast cancer prevention based on the datawe have now." As to the question of whether metformin could ever be used morebroadly beyond diabetic patients to reduce the risk of breastcancer, Chlebowski said the answer is unclear and more studies arenecessary to further analyze the linkage. While the study uncovered an association between metformin use andlower breast cancer risk in diabetic postmenopausal women, it didnot prove a cause-and-effect relationship. The U.S. Food and Drug Administration has issued warnings aboutmetformin in recent years. It requires product inserts forphysicians and patients to say that the drug has been associatedwith increased cardiovascular risks, including heart attack andstroke, and lactic acidosis, which causes fatigue, muscle pain,difficulty breathing and other symptoms. The FDA also stipulatesthat the drug literature include a warning that the drug shouldonly be used by patients with type 2 diabetes who cannot controltheir blood sugar with lifestyle or other medications. More information The U.S. National Library of Medicine has more on type 2 diabetes . SOURCES: Rowan Chlebowski, M.D., medical oncologist, Los AngelesBiomedical Research Institute, Harbor-UCLA Medical Center,Torrance, Calif.; Jennifer Ligibel, M.D., medical oncologist,Women's Cancer Program, Dana-Farber Cancer Institute, Boston;June 11, 2012, Journal of Clinical Oncology , online Last Updated: June 11, 2012 Copyright 2012 HealthDay . All rights reserved. The e-commerce company in China offers quality products such as IPL machine Manufacturer , Fractional Laser Manufacturer, and more. For more , please visit Multifunction Platform Machine today!
Related Articles -
IPL machine Manufacturer, Fractional Laser Manufacturer,
|