ABSTRACT
There are four basic criteria for choosing targeting ligand for cancer therapeutic applications: (1) the receptor is overexpressed by tumor cells, (2) the receptor participates as a principle component in the progression of the disease, (3) the receptor is stable in its present form upon the tumor cell surface, and (4) the receptor is expressed by a large percentage of tumor cells and a large variety of tumors. While BBB-targeted vector-therapeutic conjugates may be able to cross the BBB, generally they also need to target a specifi c population of cells in the brain. As transferrin receptor is overexpressed at the BBB and in glioma, the same ligand can potentially be used to target both the BBB and tumor cells in the brain.
