The tumor suppressor p53 does all it can to prevent oncogenes from transforming normal cells into tumor cells by killing defective cells or causing them to become inactive.
Sometimes oncogenes manage to initiate tumor development in the presence of p53, but, even then, the tumor suppressor doesn't give up and focuses its efforts instead on limiting the tumor's ability to invade and metastasize. A study in The Journal of Cell Biology uncovers one way that p53 acts to prevent cancer cell invasion.
A team of researchers, led by Keiko Kawauchi from the Mechanobiology Institute at the National University of Singapore, studied cells that had been transformed into cancer cells by Ras, the most common oncogene in human cancer.
They compared Ras-transformed cells with and without p53 and observed that those expressing p53 were less invasive and formed fewer focal adhesions, the molecular linkages that connect the structural scaffolding within the cell to the extracellular matrix that surrounds the cell.
The researchers found that p53 limits invasion by initiating a chain of events that ultimately prevents the formation of lamellipodia, cell membrane protrusions that spur cell movement and invasion. p53 activates a mitochondrial protease called Omi, which is then released into the cytosol of the cell when Ras causes mitochondria to fragment.
Omi cleaves actin filaments in the cytoskeleton, and the decrease in actin suppresses the activity of p130Cas, a focal adhesion signaling protein that promotes the formation of lamellipodia. With low levels of active p130Cas, cells don't form lamellipodia and are therefore less able to invade.
"Actin remodeling is a signal that prevents cell invasion," explains Kawauchi. "Most research has focused on how p53 prevents metastasis by regulating epithelial-to-mesenchymal transitions," a biological process by which cells gain migratory and invasive properties. In contrast, says Kawauchi, the new findings help explain how p53 affects the cytoskeletal processes within the cell that drive invasion.
Yamauchi, S., et al. 2014. J. Cell Biol. doi:10.1083/jcb.201309107
About The Journal of Cell Biology
The Journal of Cell Biology (JCB) is published by The Rockefeller University Press. All editorial decisions on manuscripts submitted are made by active scientists in conjunction with our in-house scientific editors. JCB content is posted to PubMed Central, where it is available to the public for free six months after publication. Authors retain copyright of their published works, and third parties may reuse the content for non-commercial purposes under a creative commons license. For more information, please visit http://www.jcb.org.
Research reported in the press release was supported by the National Research Foundation, Singapore; the Ministry of Education, Singapore; and the Kurata Memorial Hitachi Science and Technology Foundation, Japan.
Rita Sullivan King |
Gene switch may repair DNA and prevent cancer
12.02.2016 | Institute for Integrated Cell-Material Sciences at Kyoto University
New method opens crystal clear views of biomolecules
11.02.2016 | Deutsches Elektronen-Synchrotron DESY
Today, plants and microorganisms are heavily used for the production of medicinal products. The production of biopharmaceuticals in plants, also referred to as “Molecular Pharming”, represents a continuously growing field of plant biotechnology. Preferred host organisms include yeast and crop plants, such as maize and potato – plants with high demands. With the help of a special algal strain, the research team of Prof. Ralph Bock at the Max Planck Institute of Molecular Plant Physiology in Potsdam strives to develop a more efficient and resource-saving system for the production of medicines and vaccines. They tested its practicality by synthesizing a component of a potential AIDS vaccine.
The use of plants and microorganisms to produce pharmaceuticals is nothing new. In 1982, bacteria were genetically modified to produce human insulin, a drug...
Atomic clock experts from the Physikalisch-Technische Bundesanstalt (PTB) are the first research group in the world to have built an optical single-ion clock which attains an accuracy which had only been predicted theoretically so far. Their optical ytterbium clock achieved a relative systematic measurement uncertainty of 3 E-18. The results have been published in the current issue of the scientific journal "Physical Review Letters".
Atomic clock experts from the Physikalisch-Technische Bundesanstalt (PTB) are the first research group in the world to have built an optical single-ion clock...
The University of Würzburg has two new space projects in the pipeline which are concerned with the observation of planets and autonomous fault correction aboard satellites. The German Federal Ministry of Economic Affairs and Energy funds the projects with around 1.6 million euros.
Detecting tornadoes that sweep across Mars. Discovering meteors that fall to Earth. Investigating strange lightning that flashes from Earth's atmosphere into...
Physicists from Saarland University and the ESPCI in Paris have shown how liquids on solid surfaces can be made to slide over the surface a bit like a bobsleigh on ice. The key is to apply a coating at the boundary between the liquid and the surface that induces the liquid to slip. This results in an increase in the average flow velocity of the liquid and its throughput. This was demonstrated by studying the behaviour of droplets on surfaces with different coatings as they evolved into the equilibrium state. The results could prove useful in optimizing industrial processes, such as the extrusion of plastics.
The study has been published in the respected academic journal PNAS (Proceedings of the National Academy of Sciences of the United States of America).
Exceeding critical temperature limits in the Southern Ocean may cause the collapse of ice sheets and a sharp rise in sea levels
A future warming of the Southern Ocean caused by rising greenhouse gas concentrations in the atmosphere may severely disrupt the stability of the West...
12.02.2016 | Event News
09.02.2016 | Event News
02.02.2016 | Event News
12.02.2016 | Physics and Astronomy
12.02.2016 | Life Sciences
12.02.2016 | Medical Engineering