This process called angiogenesis involves a number of different growth factors and their respective receptors on the vascular wall cells. The departments of Prof. Dr. Hellmut Augustin and Prof. Dirk Schadendorf of DKFZ and Mannheim Medical Faculty of the University of Heidelberg have investigated the role of a growth factor called angiopoietin-2 (Ang2) in malignant melanoma. The docking station of Ang2 is the receptor Tie2 on the surface of endothelial cells, which form the inner lining of blood vessels. Together with other signaling molecules, Ang2 induces sprouting of endothelial cells and the formation of new capillaries.
When measuring the Ang2 concentrations in blood samples of melanoma patients, the investigators discovered that larger tumors and more advanced disease stages correlate with high levels of Ang2. If one tracks the Ang2 levels of individual patients over time, a rise parallel to disease progression can be observed. In contrast, patients who have lived with the disease for a long time, i.e., whose disease is not or only slightly progressive, have lower Ang2 levels. The scientists found out that Ang2 concentration in blood serum is a more precise indicator of the progression and stage of the disease than previously used biomarkers.
This close association between melanoma progression and Ang2 level prompted the question of whether the Ang2 growth factor really only stimulates vascularization in the tumor or whether it has additional influence on the properties of the cancer cells themselves. Such an effect had not yet been proposed for any one of the various growth factors which act on the cells of the vascular walls. Melanoma cells were really found to produce both soluble Ang2 and the matching receptor, Tie2, on their own cell membrane. As a result, they are theoretically capable of activating themselves. In order to check this, researchers switched off the Ang2 production in melanoma cells using a genetic trick. Test systems in the culture dish subsequently revealed that the skin cancer cells had lost their ability to migrate. The migration tendency of cancer cells is regarded as important information about their ability to invade other tissue in the body and metastasize.
The tumor appears to seize the signaling system of vascularization and, thus, to strengthen its malignant properties. "Ang2 is a very promising candidate," Hellmut Augustin comments on the results, „both as a biomarker for better monitoring of disease progression and as a target structure for therapy measures." Blocking Ang2 might not only attack the tumor's blood supply, but also reduce its malignant growth.
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23.10.2017 | Penn State
Key discoveries offer significant hope of reversing antibiotic resistance
23.10.2017 | University of Bristol
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
23.10.2017 | Event News
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