A brief talk on the brain cancer vaccine
With the rapid development of molecular biology and biotechnology, people's understanding of cancer has reached the molecular level, and began to try to prepare tumor vaccines and apply them to cancer treatment by means of genetic engineering according to the theory of tumor immunity. The design principle of cancer vaccine is to prepare cancer vaccine around how to enhance the immunogenicity of tumors and the body's anti-tumor immune response, and how to break the immune tolerance of tumors and the cgamp. An ideal cancer vaccine can not only induce active immunity and stimulate the host to produce an effective immune response, but also provide a protective long-term immune memory function for preventing recurrence of tumors. Tumor antigen polypeptide vaccines are expected to isolate, purify and amplify tumor antigens, increase the uptake and processing of tumor antigens by antigen presenting cells, and ultimately induce specific immune responses to tumor antigens. Nucleic acid vaccine (DNA vaccine) is a gene fragment encoding an antigen 19 9 cloned into an eukaryotic expression plasmid, and then immunized animals with the plasmid DNA. Antigen-coding genes can be expressed in the host and stimulate its production of humoral and cellular immune responses. Genetically engineered vaccines are used to modify tumor cells or antigen 19 9 presenting cells with some functional genes by means of transgene. Genes encoding key components of immune response are transferred into tumor cells in vitro, so as to increase the immunogenicity of vaccines and promote the activation of tumor-specific T cells.
Gliomas are common primary tumors of the nervous system. Most of them are malignant. The median survival time of the patients is less than 16 months. Because of the high invasiveness of glioma, surgery is difficult to completely resect, so it is very easy to recur. Radiotherapy can not kill all cancer cells, and the adverse reactions are large, which can easily lead to radiation bacterial vaccines. Chemotherapy has serious adverse reactions and is prone to drug resistance and other problems. Therefore, the emergence of gene therapy provides a new way for the treatment of glioma when conventional methods such as surgery, radiotherapy and chemotherapy can not effectively treat glioma. At present, gene drugs such as small interfering RNA have shown good therapeutic effect and broad application prospects in preclinical research. However, because the blood-brain barrier prevents more than 98% of small molecules and almost all macromolecules from entering the brain, many drugs that have good therapeutic effects on peripheral system tumors are ineffective in the treatment of glioma. In addition, siRNA is easy to degrade, and because of the same charge rejection and renal filtration of cell membranes, siRNA must be transported into target cells effectively by means of vectors. Therefore, the design and construction of gene drug delivery system that can effectively enter the brain cancer vaccine has been one of the hot research fields in pharmacy.
The effectiveness and safety of cancer vaccine will become an important research topic in the future. However, there are some problems in the research of cancer vaccine, such as the tumorigenicity of cancer vaccine. This requires researchers to further carry out accurate quantitative experiments on tumorigenicity of cancer vaccines in order to reduce toxicity and prevent benzodiazepine oxazepam. Secondly, most of the studies on cancer vaccines are still in the stage of in vitro or animal trials. Although some of them have entered the stage I or II clinical trials, there are few trials and applications in humans. In addition, the theory of cancer vaccine is insufficient and lacks more theoretical support. It is believed that with the deepening of cancer immunity research and the improvement of cancer vaccine technology, cancer vaccine will make the treatment of cancer more hopeful and save more cancer patients.
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