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.
When Air is in Short Supply - Shedding light on plant stress reactions when oxygen runs short
23.03.2017 | Institut für Pflanzenbiochemie
WPI team grows heart tissue on spinach leaves
23.03.2017 | Worcester Polytechnic Institute
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
23.03.2017 | Life Sciences
23.03.2017 | Power and Electrical Engineering
23.03.2017 | Earth Sciences