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1 Xenograft Model of Human Brain Tumor

In the life sciences, scientists are paying more and more attention to the human brain, the essential center of the body. The gliomas in human brains are especially unique challenges for doctors due to the difficulties of identifying early cancer lesions and little effective treatments. Gliomas account for about half of the central nervous system tumors. Due to its invasive growth and other malignant behaviors, gliomas are difficult to be radically cured; moreover, most of gliomas are difficult to be early detected, even they are discovered, it is difficult to cure them because of their resistance to radiation or chemotherapy. Therefore, developing animal models of human gliomas is essential for us to explore the mechanisms of occurrence and development of brain tumor and promote clinical research. From past to future, the far-sighted men attached and will continue to attach importance to the development of animal models of human gliomas. Judging from the research and development process, human beings have, after a hundred years’ efforts, moved from the development and application of animal models of spontaneous and induced brain tumor to the generation of the experimental platform of various animal models of human brain tumors. Now we are trying to improve the simulation of the animal models to the human diseases. For the human glioma, the early model was the solid tumors formed by directly inoculating in vitro passaged cell lines to animals; then, human glioma tissue were successfully inoculated into animals. In recent years, with the progress of tumor molecular biology, transgenic or gene knockout procedures are used to generate genetic engineering mouse brain tumor model, which meet the requirement of finding the molecular etiology of human brain tumors through specific molecular genetics. After the successful cloning of glioma stem cells, the establishment of animal models retaining the characteristics of glioma stem cells is on the agenda. In short, although we face difficulty building up animal models of brain tumor, we have tried to imitate the models to diseases from the system-cell level to the system-cells -molecular level.