American scientists claim to have developed a vaccine that prevents the development and progression of breast cancer in mice. The results of this study, published in Nature Medicine, are being prepared for further confirmation with human trials. However, they stress that it will take several years before this vaccine is widely used in clinical trials. The immunologists leading the trial say the vaccine targets a protein found in most breast cancers. Vincent Tuohy of the Lerner Research Institute in Cleveland: We believe that this vaccine will be used someday in the future to prevent breast cancer in the same way that we use vaccines to prevent childhood diseases. “If it works in humans as well as it does in mice, it will be a milestone that we will eradicate breast cancer.” In the study, half of the tumor genetically susceptible mice were vaccinated with the á-lactalbumin-containing vaccine and the other half were vaccinated without the á-lactalbumin-containing vaccine. The á-lactalbumin-containing vaccine group developed no breast cancers, while the other group developed all breast cancers. Previously, 2 tumor vaccines have been approved in the United States, a cervical cancer vaccine and a liver cancer vaccine. However, these two vaccines targeted human papillomavirus and hepatitis B virus, respectively, rather than the products of the tumors themselves. From the perspective of developing preventive vaccines, tumor vaccines face a problem not encountered in the development of viral vaccines – viruses can be recognized by the immune system as foreign invaders, whereas tumors are not. A tumor is an overgrowth of cells in the body. Immunosuppression of this class of cells will similarly immunosuppress the recipient (host or patient) itself and destroy healthy tissue. ”The significance of this research tells us how we can prevent breast cancer in the future,” said Caitlin Palframan of the Beat Breast Cancer charity. “Nonetheless, this is an early stage trial and we look forward to the results of subsequent large-scale clinical trials to test whether the vaccine is safe and effective in humans.” She added that a number of approaches have been gained in reducing the risk of breast cancer in women, including lowering alcohol intake, maintaining a healthy weight and exercising properly. Professor Robert Hawkins of Cancer Research UK said:This preliminary study provides an intriguing avenue for breast cancer prevention. “The vaccine will also be studied for its safety and efficacy over several years of full-scale trials as a method of preventing breast cancer in women.”