Role of Ion Channels and Amino-Acid Transporters in the Biology of Astrocytic Tumors
The malignant transformation of central nervous system (CNS) glial cells gives rise to tumors that are collectively called gliomas. Although the vast majority of these cancers are believed to be of astrocytic origin, the actual cell of origin remains unknown. While gliomas present with many of the same genetic alterations in tumor suppressor genes or oncogenes that are common amongst cancers, their biology differs quite significantly from that of other neoplasms. Importantly, their growth is limited by the size of the skull, and hence tumor expansion can only occur when normal brain is destroyed. Recent research suggests that gliomas accomplish this by releasing glutamate at concentrations that cause excitotoxic neuronal cell death. Peritumoral glutamate may also contribute to seizures, which are a common comorbidity in patients with malignant glioma. Another differentiating feature of gliomas is their unusual ability to spread by diffusely invading normal brain tissue rather than...
KeywordsGlioma Cell Malignant Glioma Glutamate Release Glioma Cell Invasion Culture Glioma Cell
α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors
Channels big conductance Ca2+-activated
Central nervous system
Excitatory amino acid transporter
Glial l-glutamate transporter
Matrix metalloproteinase II
The author is grateful for the continued support by grants from the National Institutes of Health RO1 NS-31234, RO1 NS-52634, RO1 NS-36692, and P50-CA97247.
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