Medical researchers are moving forward along a number of fronts in the battle to better diagnose and treat malignant brain tumors similar to that now afflicting Sen. Edward Kennedy, D-Mass.
Link: Research on Brain Tumors Abounds
One area of investigation focuses on gene therapy. STAT3 is a gene that ensures neural stem cells will develop into astrocytes, or the brain and spinal cord cells that provide nutrients to tissue and perform other functions. However, mutated forms of STAT3 often act as oncogenes that lead to the formation of tumors, and most brain cancers arise in astrocytes rather than in neurons.
But this year, a research team at the Harvard Medical School in collaboration with colleagues at the Dana-Farber Cancer Institute demonstrated that STAT3 also can serve as a tumor suppressor, depending on the genetic composition of the patient. The investigators discovered that STAT3 will act as an oncogene if another gene known as EGFR is mutated, but it will operate as a suppressor if the gene PTEN is altered from its normal state.
Unfortunately, if a significant number of PTEN genes are mutated, the beneficially suppressing effect of STAT3 may be reduced.
If researchers can develop a deeper understanding of the genetic subtleties underlying cancerous growths in the presence of STAT3, they will be able to provide more effective treatments. In some cases, STAT3 will need to be inhibited, and such repression would be avoided in other cases.
Another area of research focuses on the breakdown of the dense cellular membrane lining the interior of blood capillaries and that protects the brain from harmful substances. If this blood-brain barrier is ruptured, cancerous cells may be able to enter the central nervous system.
Only 2 percent of cancer fatalities result from primary brain tumors; many more deaths are caused by secondary tumors in the central nervous system. Researchers at the University of Adelaide are focusing on the effect that neuropeptides, or polymers of amino acid, may have on the permeability of blood vessels near a tumor, hopefully leading to better methods to prevent seepage that could lead to secondary growths.
Finally, investigators at the cancer research center City of Hope in Duarte, Calif., are collaborating with NASA researchers on the development of carbon nanotubes that will be able to ribonucleic acid, DNA and chemical agents designed to inhibit cancer cell growth. These extremely strong yet supple, hollow cylindrical tubes, measuring a few nanometers in diameter (where a nanometer is one-billionth of a meter in length), were originally developed for applications in space but now offer a promising and precise method for targeting tumors. Experiments with mice have have demonstrated that these nanotubes do not harm brain cells or the ability of the cells to reproduce.
Source: JournalGazette.net; Gerald Voland
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