Fibroblasts invade at a snail's pace
Study finds Snail1 may spur cancer cells by stimulating tissue invasion and angiogenesis
A transcription factor known to drive the formation of fibroblasts during development also promotes their ability to invade and remodel surrounding tissues, report Rowe et al. in the February 9, 2009 issue of the Journal of Cell Biology.
The conversion of epithelial cells into fibroblast-like mesenchymal cells is a critical event in both normal development and cancer. The transcription factor Snail1 induces this conversion (known as epithelial–mesenchymal transition, or EMT) by repressing the expression of epithelial-specific genes. Little was known about Snail1's role after EMT, although the transcription factor is up-regulated in mesenchymal tissue surrounding tumors and wounds.
Because Snail1 expression is thought to be required for maintenance of the mesenchymal phenotype in cancer, Rowe et al. were surprised to see that normal fibroblasts retained many mesenchymal characteristics when Snail1 was removed. The authors did find, however, that many genes important for cell motility, such as actin-binding proteins and matrix metalloproteinases, were expressed at lower levels in fibroblasts lacking Snail1.
Cells invade tissues by sending out actin-rich protrusions called invadopodia that contain proteolytic enzymes that degrade the surrounding extracellular matrix (ECM). Fibroblasts without Snail1 formed fewer invadopodia and were less able to degrade the ECM. Rowe et al. transplanted the Snail1-deficient fibroblasts into chick embryos and found that they were completely unable to penetrate the basement membrane and the complex mix of ECM proteins beneath. Moreover, unlike wild-type fibroblasts, Snail1-deficient cells didn't stimulate the ingrowth of new blood vessels—another key function of fibroblasts during wound healing and tissue remodeling.
The team thinks that in addition to its role in EMT, Snail1 also acts as a master regulator of fibroblast function. In cancer cells, says author Grant Rowe, sustained Snail1 expression may not only cause a loss of epithelial markers but also promote tumor aggression by stimulating tissue invasion and angiogenesis.
Rita Sullivan | EurekAlert!
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.
Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...
Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.
Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...
Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.
As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...
Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.
With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...
Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine
Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...