Moreover, it is often impossible to identify all the fine extensions by which the tumor spreads into surrounding healthy tissue. To at least slow down the growth of tumor cells that have remained in the head, almost all glioblastoma patients are treated by radiotherapy after surgery.
"Unfortunately, we can only delay cancerous growth in this way, but we cannot cure patients. The tumor cells, especially the cancer stem cells, are very resistant to radiation," says Prof. Dr. Dr. Peter Huber, who is head of the Clinical Cooperation Unit 'Radiation Oncology' at the German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ).
Studies conducted in recent years found that response to radiation therapy in various cancers is better when certain types of cellular growth factors are blocked at the same time. Glioblastoma cells often produce large amounts of a growth factor called TGF-β (transforming growth factor beta). High levels of TGF-β in these tumors are correlated with particularly aggressive growth and a poor prognosis. In addition, the factor seems to support the self-renewal capability of glioblastoma stem cells. "We therefore suspect that blocking TGF-β signaling pathways slows down the self-renewal of cancer stem cells and, thus, may improve radiation treatment outcomes," Peter Huber adds, explaining the background of the study now published.
In collaboration with colleagues from, among others, the Radiology Department of Heidelberg University Hospitals and a DKFZ department led by Prof. Dr. Ana Villalba, Huber's team investigated the effect of a combination of radiation treatment and a newly developed substance called LY2109761. This substance blocks the signals that are transmitted into cells by the TGF-β receptor. The investigators first studied glioblastoma cells in tissue samples taken during surgical removal of the tumors. Irradiation combined with adding the substance reduced the self-renewal capability of tumor stem cells and delayed their growth significantly better than radiation treatment alone.
The group transplanted human glioblastoma cells into the brains of mice and found that these animals, after receiving the combination therapy, survived longer than those animals treated by radiotherapy alone. Tissue studies showed that, under the combination therapy, tumors grew more slowly and less invasively and showed a lower density of newly formed blood vessels. "Paradoxically, radiation therapy can provoke aggressive growth behavior in surviving tumor cells. LY2109761 seems to prevent this fatal effect," says Huber, explaining how the drug seems to work.
Blocking of TGF-β signaling produced such promising results that researchers will now conduct a multicenter clinical trial to find out whether this mechanism may also slow down glioblastoma growth in patients more effectively than the current standard treatment. Led by Prof. Dr. Wolfgang Wick, who is head of a collaboration unit of DKFZ and the Neurology Department of Heidelberg University Hospitals, the combination therapy will be tested in Germany (Heidelberg), Spain, and the U.S.A.
Mengxian Zhang, Susanne Kleber, Manuel Röhrich, Carmen Timke, Na Han, Jochen Tuettenberg, Ana Martin-Villalba, Jürgen Debus, Peter Peschke, Ute Wirkner, Michael Lahn and Peter E. Huber: Blockade of TGF-beta signaling by the TGFβR-I kinase inhibitor LY2109761 enhances radiation response and prolongs survival in glioblastoma. Cancer Research 2011, DOI:10.1158/0008-5472.CAN-11-1212
The German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ) with its more than 2,500 employees is the largest biomedical research institute in Germany. At DKFZ, more than 1,000 scientists investigate how cancer develops, identify cancer risk factors and endeavor to find new strategies to prevent people from getting cancer. They develop novel approaches to make tumor diagnosis more precise and treatment of cancer patients more successful. Jointly with Heidelberg University Hospital, DKFZ has established the National Center for Tumor Diseases (NCT) Heidelberg where promising approaches from cancer research are translated into the clinic. The staff of the Cancer Information Service (KID) offers information about the widespread disease of cancer for patients, their families, and the general public. The center is a member of the Helmholtz Association of National Research Centers. Ninety percent of its funding comes from the German Federal Ministry of Education and Research and the remaining ten percent from the State of Baden-Württemberg.
Dr. Sibylle Kohlstädt | EurekAlert!
Resolving the mystery of preeclampsia
21.10.2016 | Universitätsklinikum Magdeburg
New potential cancer treatment using microwaves to target deep tumors
12.10.2016 | University of Texas at Arlington
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences