Home Reports Life Sciences Content
next article
24.02.2012
Although it?s widely accepted that inflammation is a critical underlying factor in a range of diseases, including the progression of cancer, little is known about its role when normal cells become tumor cells.
Now, scientists from the Florida campus of The Scripps Research Institute have shed new light on exactly how the activation of a pair of inflammatory signaling pathways leads to the transformation of normal breast cells to cancer cells.
The study, led by Jun-Li Luo, an assistant professor at Scripps Florida, was published online before print by the journal Molecular Cell on February 23, 2012.
The scientists? discovery points to the activation of a self-sustaining signaling circuit that inhibits a specific RNA, a well-known tumor suppressor that helps limit the spread of cancer (metastasis). Therapies that disable this circuit and halt this miRNA repression could have the potential to treat cancer.
The Spark that Ignites Trouble
In the new study, scientists identified the specific pathways that transform breast epithelial cells into active cancer cells.
The researchers found immune/inflammatory cells ignite the transient activation of MEK/ERK and IKK/NF-kB pathways; the MEK/ERK pathway then directs a consistent activation of a signaling circuit in transformed cells. This consistent signaling circuit maintains the malignant state of the tumor cells.
Luo compares this process to starting a car?a car battery starts the engine much like the transient signal activation turns on the consistent signal circuit. Once the engine is started, it no longer needs the battery.
The scientists go on to show that the initial activation of these pathways also activates IL6, a cytokine involved in a number of inflammatory and autoimmune diseases, including cancer. IL6 acts as a tumor initiator, sparking the self-sustaining circuit in normal breast cells necessary for the initiation and maintenance of their transformed malignant state.
In establishing that self-sustaining signal circuit, IL6 represses the action of microRNA-200c, which is responsible for holding down inflammation and cell transformation. Since enhanced microRNA-200c expression impairs the growth of existing cancer cells and increases their sensitivity to anti-tumor drugs, compounds that disable microRNA-200c repression have the potential to act as a broad-spectrum therapeutic.
Interestingly, the new findings dovetail with the ?multiple-hits theory? of tumor formation, which posits that once normal cells in the human body accumulate enough pre-cancerous mutations, they are at high-risk for transformation into tumor cells. While the newly described initial pathway activation is momentary and not enough to cause any lasting changes in cell behavior, it may be just enough to tip the cell?s transformation to cancer, especially if it comes on top of an accumulation of other cellular changes.
The first author of the study, ?IL6-Mediated Suppression of Mir-200c Directs Constitutive Activation of an Inflammatory Signaling Circuit That Drives Transformation and Tumorigenesis,? is Matjaz Rokavec of Scripps Research. Other authors include Weilin Wu, also of Scripps Research.
The study was supported by the National Institute of Health, the United States Department of Defense, the Florida Department of Health, and Frenchman?s Creek Women for Cancer Research.
About The Scripps Research Institute
The Scripps Research Institute is one of the world's largest independent, non-profit biomedical research organizations. Scripps Research is internationally recognized for its discoveries in immunology, molecular and cellular biology, chemistry, neuroscience, and vaccine development, as well as for its insights into autoimmune, cardiovascular, and infectious disease. Headquartered in La Jolla, California, the institute also includes a campus in Jupiter, Florida, where scientists focus on drug discovery and technology development in addition to basic biomedical science. Scripps Research currently employs about 3,000 scientists, staff, postdoctoral fellows, and graduate students on its two campuses. The institute's graduate program, which awards Ph.D. degrees in biology and chemistry, is ranked among the top ten such programs in the nation. For more information, see www.scripps.edu.
For information:
Mika Ono
Tel: 858-784-2052
Fax: 858-784-8136
mikaono@scripps.edu
Mika Ono | Source: EurekAlert!
Further information: www.scripps.edu
next article
Overview of the latest five Focus news of the innovations-report:
In the focus: How the brain communicates
An important mechanism by which the human brain hemispheres communicate with each other has been discovered by a team of researchers from Berlin and the University of Bern.
The findings, which appear in the current issue of the journal Science, provide new insights into nerve cell communication in the brain that could also play a role in stroke.
On the way to the brain, nerve pathways in the human body cross each other. As a result, stimuli are processed ...
In the focus: Accelerated Search for Active Agents to Treat Alzheimer?s and Parkinson?s
Professor Erich Wanker of the Max Delbr?ck Center for Molecular Medicine (MDC) Berlin-Buch and of the Excellence Cluster Neurocure is to receive EUR 675 000 in funding from the Helmholtz Association over the next two years.
The grant shall be used to accelerate the search for active agents to treat diseases that are caused by protein misfolding. These include Alzheimer?s and Parkinson?s. The grant amount will be matched by the MDC, a member institution of the Helmholtz Association, which means that the total funding for the ...
In the focus: UC Santa Barbara researcher's new study may lead to MRIs on a nanoscale
Magnetic resonance imaging (MRI) on the nanoscale and the ever-elusive quantum computer are among the advancements edging closer toward the realm of possibility, and a new study co-authored by a UC Santa Barbara researcher may give both an extra nudge. The findings appear today in Science Express, an online version of the journal Science.
Ania Bleszynski Jayich, an assistant professor of physics who joined the UCSB faculty in 2010, spent a year at Harvard working on an experiment that coupled nitrogen-vacancy centers in diamond to nanomechanical resonators. That project is the basis for the new paper, "Coherent sensing of a mechanical resonator with a ...
In the focus: Penn Researchers Build First Physical ?Metatronic? Circuit
The technological world of the 21st century owes a tremendous amount to advances in electrical engineering, specifically, the ability to finely control the flow of electrical charges using increasingly small and complicated circuits. And while those electrical advances continue to race ahead, researchers at the University of Pennsylvania are pushing circuitry forward in a different way, by replacing electricity with light.
?Looking at the success of electronics over the last century, I have always wondered why we should be limited to electric current in making circuits,? said Nader Engheta, professor in the electrical and systems engineering department of Penn?s School of Engineering and Applied Science. ?If we moved to shorter wavelengths ...
In the focus: Metal nanoparticles shine with customizable color
A new way to create and control color has implications for display screens and security tags
Engineers at Harvard have demonstrated a new kind of tunable color filter that uses optical nanoantennas to obtain precise control of color output.
Whereas a conventional color filter can only produce one fixed color, a single active filter under exposure to different types of light can produce a range of colors.
The ...
caroline manzo caroline manzo the haunting in connecticut ashram ashram merce cunningham tim hightower
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.