Arturo Alvarez-Buylla and Erica L. Jackson, of the University of California, San Francisco, and colleagues reported their findings in a paper in the July 20, 2006, Neuron, published by Cell Press. In their studies, they sought to discover whether neural stem cells in the brain called B cells carry a receptor--known as platelet-derived growth factor receptor á (PDGFRá)--for the signaling molecule PDGF.
Neural stem cells are immature cells that serve as the continual source of new brain cells in adults, and PDGF is known as an important regulator of such cells. Also, PDGF has been implicated as a key signaling molecule underlying the formation of brain tumors. PDGF triggers such cell response by plugging into the target receptor on the stem cell, like a key inserting into a lock.
There had been indirect evidence that neural stem cells give rise to brain tumors. "However, it has not been shown in vivo that tumor stem cells are derived from normal stem cells or that a specific population of cells with demonstrated stem cell properties is capable of initiating tumor formation," wrote the researchers.
Using tracers, the researchers discovered that PDGFRá is, indeed, found on the stem cells in both mouse and human brain tissue. They also found that the receptor is triggered by PDGF in the stem cells to regulate their production of mature brain cells. The researchers located the PDGFRá-containing cells in the subventricular zone (SVZ) of the brain, which is the center for production of new brain cells in adults.
The researchers also found that infusing PDGF into mouse brain caused abnormal growth--called hyperplasia--of tumor-like nodules that invaded surrounding brain tissue. Their analysis indicated that the PDGF infusion caused the stem cells to halt their normal production of mature brain cells and launch into the abnormal proliferation pathway. Importantly, the researchers found that stopping the PDGF infusion caused a complete regression of the nodules.
The researchers wrote that "these findings are significant due to our limited knowledge of surface markers for neural stem cells. Our data also provide evidence of a link between these PDGFRá B cells and the early changes associated with tumor initiation, suggesting they may be targets of neoplastic transformation. The regression of atypical hyperplasia after PDGF removal described here suggests that inhibition of PDGF signaling could provide a useful therapy for those gliomas in which the pathway is upregulated, especially given the recovery of the normal architecture after regression of the hyperplasia."
In a preview of the paper in the same issue of Neuron, Santosh Kesari and Charles D. Stiles wrote that the new findings "lend weight" to the argument that the stem cells identified by Alvarez-Buylla and his colleagues are the cells or origin for malignant gliomas. They wrote that such work offers "therapeutic opportunities," emphasizing that "the people that matter the most do not have the luxury of time to watch this work unfold. The median interval from diagnosis to death for patients with malignant glioma is currently only 14 months."
A novel socio-ecological approach helps identifying suitable wolf habitats
17.02.2017 | Universität Zürich
New, ultra-flexible probes form reliable, scar-free integration with the brain
16.02.2017 | University of Texas at Austin
In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".
Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
20.02.2017 | Materials Sciences
20.02.2017 | Health and Medicine
20.02.2017 | Health and Medicine