Porous "micro-patches" against breast cancer
Researchers at the Houston Methodist Clinic, working under the guidance of Dr. Haifa Shen, have demonstrated in experiments on animal models that the use of silicon oxide microparticles as carriers significantly increases the effectiveness of the breast cancer vaccine.
The principle of action of antitumor vaccines, the development of which is one of the priorities of modern oncology, is based on the stimulation of a selective antitumor response in the patient's body. Since 2010, the U.S. Food and Drug Administration has approved a number of vaccines and other immunotherapeutic drugs against melanoma, prostate and lung cancer. Currently, many vaccines against various oncological diseases are at different stages of clinical research.
Despite the fact that breast cancer is one of the most common oncological diseases, there is currently no officially approved vaccine for its treatment. The most promising target for such a vaccine is the HER2 protein, a receptor for epidermal growth factor localized on the cell surface, the hyperexpersion of which is characteristic of tumor cells in 15-30% of patients with this disease.
A vaccine against HER2 would set up the immune system to fight cancer cells overexpressing it with minimal harm to healthy cells. However, so far, experimental vaccines of this type have provided only moderate positive results.
The authors believe that the main reason for these failures is the ineffective delivery of the vaccine. They propose to solve this problem with the help of silicon dioxide microparticles with a diameter of about 1 micrometer. These particles are riddled with many hollow tubules that can be filled with antigens such as HER2. The use of such particles as carriers not only protects protein molecules of antigens from premature destruction, but also stimulates immune cells to recognize cancer cells expressing them.
In vitro and in vivo studies have demonstrated the ability of microparticles to induce a strong and stable immune response in areas of tumor activity and growth, even in the absence of an antigen. At the same time, even a single dose of HER2-loaded microparticles completely stopped the growth of tumors in animal models.
The authors believe that such microparticles can be used to deliver any cancer antigens and even their combinations into the body, which theoretically can increase the effectiveness of vaccines. However, they also note that before starting clinical trials of such vaccines, it is necessary to assess the safety of carrier microparticles for the body.
Article by Xiaojun Xia et al. Porous Silicon Microparticle Potentiates Anti-Tumor Immunity by Enhancing Cross-Presentation and Inducing Type I Interferon Response is published in the journal Cell Reports.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of the Houston Methodist:
Breast cancer vaccines may work better with silicon microparticles.
12.05.2015