TUESDAY, Jan. 16, 2007 (HealthDay News) -- Small blood vessels associated with brain tumors create a nurturing environment for self-renewing cancer stem cells, U.S. researchers report.
They also found that antiangiogenic drugs that disrupt this environment reduce the number of cancer stem cells and halt tumor growth.
Cancer stem cells comprise only a small fraction of most brain tumors but play a critical role in tumor growth and survival, according to background information in the study, published in the January issue of the journal Cancer Cell.
Researchers at St. Jude's Children's Research Hospital in Memphis found that cancer stem cells in human brain tumors are associated with blood vessels and that, in culture, vascular cells interact with and help brain cancer stem cells survive. This kind of interaction was not seen in most kinds of non-cancer stem cell tumor cells.
The researchers also transplanted human brain tumors, with or without vascular cells, into mice. The mice that received the vascular cells showed an increase in cancer stem cells and increased tumor activity.
When the mice were given antiangiogenic drugs to diminish tumor blood vessels, the team saw a reduction in cancer stem cells. Tumor growth was also halted, the study authors said.
"Our data identify a possible role for niche microenvironments in the maintenance of CSCs (cancer stem cells) and identify a mechanism by which antiangiogenic drugs inhibit brain tumor growth," researcher Dr. Richard J. Gilbertson said in a statement. "If the notion that niches protect CSCs proves correct, then targeting these microenvironments could prove highly effective treatments of cancer."
More information
The U.S. National Cancer Institute has more about brain tumors.
