8/21/2009
Noteworthy work out of Tufts University Medical Center has led researchers to believe that a new approach to treating brain tumors may be on the horizon.
Noteworthy work out of Tufts University Medical Center has led researchers to believe that a new approach to treating brain tumors may be on the horizon.
Cancer stem cells are thought to play an integral role in brain tumor formation, including the formation of glioblastomas (GBM), a most aggressive and intractable type of brain tumor. Researchers at Tufts University Medical Center report that a specific gene – STAT3 – may have important regulatory functions in cancer stem cells. The inhibition of the protein encoded by the STAT3 gene in cancer stem cells might be effective in killing cancer stem cells that give rise to the mature GBM tumor cells and result in more effective brain tumor therapies.
It has been known for some time that the STAT3 gene is activated in a number of human cancers including brain tumors. However, the recently published results by Cochran et al is one of the first studies to demonstrate its regulation of brain tumor cancer stem cells.
Brent Cochran, Ph.D, and his colleagues at Tufts Medical Center treated cancer stem cells isolated from surgically removed glioblastoma tumors with two distinct STAT3 inhibitors (STA-21 and S31-201). The cells treated with STAT3 inhibitors showed significantly less growth than control cells that were not treated with STAT3 inhibitors. Additionally, STAT3 inhibition also apparently turned off the production of particular proteins involved in stem cell maintenance, causing the cancer stem cells to permanently lose their stem cell characteristics. These results suggest that STAT3 regulates a number of GBM cancer stem cell activities including growth and division.
Because current cancer therapies focus on mature tumor cells and do not specifically target cancer stem cells, Cochran's work may shift the way we think about cancer treatments. Cancer stems cells have proven to be the highly resistant to conventional radiotherapy and chemotherapy. In many cases, the cancer stem cells are not destroyed by these approaches, leaving patients vulnerable to tumor recurrence and growth.
Targeted inhibition of STAT3 may be the answer. If STAT3 can be effectively and safely inhibited in brain tumor patients, cancer stem cells may lose their ability to govern tumor growth, spread, and recurrence and hopefully halt tumor formation.
"I hope that our future research investigating the mechanisms involved in inhibiting STAT3 will contribute to more effective and less invasive cancer therapies," said Cochran.
As do we, Dr. Cochran.
The National Brain Tumor Society is glad to have been able to support Dr. Cochran's work though its brain tumor research grants.
