摘要 |
It has been discovered that cells such as genetically engineered fibroblasts and keratinocytes can be cultured in the cyst fluid of encapsulated tumors. This provides a means for proliferating genetically engineered producer cells within these types of tumors, increasing the number of cells producing viral particles, which then transduce the surrounding tumor cells with the genetic material, in the preferred embodiment, a lethal gene. A number of different tumor types form "cysts", which contain fluid produced by the tumor cells, including brain tumor cells such as gliomas, and many types of breast, and lung tumors. These cyst fluids have been shown to contain elevated levels of certain growth factors, for example, fibroblast growth factor (FGF) and epidermal growth factor (EGF). The types of genetically engineered cells to be used can be selected in part according to the levels of growth factors in the cyst fluid which most promote growth of the cells, for example, cystic tumors with high levels of FGF would be injected with genetically engineered fibroblasts; cystic tumors with high levels of EGF would be injected with genetically engineered keratinocytes; and cystic tumors with high levels of vascular endothelial growth factor (VEGF) would be injected with genetically engineered endothelial cells.
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