Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

CSHL scientists identify and repress breast cancer stem cells in mouse tissue

19.12.2007
An approach based on the manipulation of microRNAs

By manipulating highly specific gene-regulating molecules called microRNAs, scientists at Cold Spring Harbor Laboratory (CSHL) report that they have succeeded in singling out and repressing stem-like cells in mouse breast tissue – cells that are widely thought to give rise to cancer.

“If certain forms of breast cancer do indeed have their origin in wayward stem cells, as we believe to be the case, then it is critical to find ways to selectively attack that tumor-initiating population,” said Gregory Hannon, Ph.D., CSHL professor and Howard Hughes Medical Institute Investigator. Hannon also is head of a lab focusing on small-RNA research at CSHL and corresponding author of a paper reporting the new research, published in the latest issue of Genes and Development.

“We have shown that a microRNA called let-7, whose expression has previously been associated with tumor suppression, can be delivered to a sample of breast-tissue cells, where it can help us to distinguish stem-like tumor-initiating cells from other, more fully developed cells in the sample. Even more exciting, we found that by expressing let-7 in the sample, we were able to attack and essentially eliminate, very specifically, just that subpopulation of potentially dangerous progenitor cells.”

... more about:
»CSHL »Hannon »MicroRNA »progenitor »sample »stem-like

The study was done in collaboration with Senthil Muthuswamy Ph.D., an expert in breast cancer research who heads a CSHL lab focusing on understanding the changes in the biology of breast epithelial cells during the initiation and progression of cancer. Dr. Muthuswamy emphasized that a key ingredient that made this study successful is the use of a mouse breast-derived model cell system called COMMA-1D that not only includes differentiated cells but also stem-like progenitors, in varying stages of maturity, or differentiation.

Unexpected Impact of Conventional Chemotherapy

No therapies currently exist that target stem-like tumor-initiating cells, whose existence in diverse tissues including breast, lung, brain and colon, as well as in the blood, has been demonstrated in a line of research stretching back to 2001. In that year, John E. Dick of the University of Toronto identified cancer stem cells in the blood of leukemia patients.

The cancer stem cell hypothesis is controversial, in part, because of the challenge it represents for current cancer therapy, which regards all tumor cells as potentially capable of spreading the disease, and which seeks to reduce tumor mass and destroy the maximum possible number of tumor cells. In the cancer stem cell hypothesis, reduction of tumor volume alone will not suffice if the stem cells which originally gave rise to the cancer are not specifically targeted and destroyed.

The new Cold Spring Harbor Laboratory research not only suggests one possible way of accomplishing this therapeutic goal – the Hannon lab is initiating a demonstration study in mice – but it also demonstrated that one component of a chemotherapy cocktail currently used as first-line therapy against certain kinds of breast cancer has the potential to actually enrich the subpopulation of stem-like cells that serve as cancer progenitors.

“We found that administration of cyclophosphamide in our mouse cell sample had the effect of enriching for these cells,” Hannon said, “which suggests that we need to look carefully at these therapies in model systems to see if the effects we see in cell culture are mirrored in real tumors – and then, to gauge what effect that has on metastasis and relapse following therapy.”

It has been known for some time that stem and progenitor cells possess unique defenses, as compared with mature, or differentiated cells, which, unlike their stem-like “mothers” do not have the capacity to renew themselves or to generate multiple cell-types. Stem cells, for instance, are thought to be able to “pump” toxins out of their cellular domain, much as do fully differentiated tumor cells that have developed resistance to chemotherapy.

Jim Bono | EurekAlert!
Further information:
http://www.cshl.edu

Further reports about: CSHL Hannon MicroRNA progenitor sample stem-like

More articles from Life Sciences:

nachricht Bacteria as pacemaker for the intestine
22.11.2017 | Christian-Albrechts-Universität zu Kiel

nachricht Researchers identify how bacterium survives in oxygen-poor environments
22.11.2017 | Columbia University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Corporate coworking as a driver of innovation

22.11.2017 | Business and Finance

PPPL scientists deliver new high-resolution diagnostic to national laser facility

22.11.2017 | Physics and Astronomy

Quantum optics allows us to abandon expensive lasers in spectroscopy

22.11.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>