Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A new link between stem cells and tumors

05.09.2005


Scientists at the European Molecular Biology Laboratory (EMBL) in Heidelberg and the Institute of Biomedical Research of the Parc Científic de Barcelona (IRB-PCB) have now added key evidence to claims that some types of cancer originate with defects in stem cells. The study, reported this week in the on-line edition of Nature Genetics (September 4) shows that if key molecules aren’t placed in the right locations within stem cells before they divide, the result can be deadly tumors.



Cells in the very early embryo are interchangeable and undergo rapid division. Soon, however, they begin differentiating into more specific types, finally becoming specialized cells like neurons, blood, or muscle. As they differentiate, they should stop dividing and usually become embedded in particular tissues. Some tumor cells are more like stem cells because they are identical, they divide quickly, and in the worst case - metastasize - they wander through the body and implant themselves in new tissues.

Specialized cells may die through age or injuries, so the body keeps stocks of stem cells on hand to generate replacements. Usually the stem cell divides into two types: one that is just like the parent, which is kept to maintain the stock, and another that differentiates. This is what happens with neuroblasts. Cell division creates one large neuroblast and a smaller cell that can become part of a nerve. This process is controlled by events that happen prior to division. The parent cell becomes asymmetrical: it collects a set of special molecules, including Prospero and other proteins, in the area that will bud off and become the specialized cell.


"This asymmetry provides the new cell with molecules it needs to launch new genetic programs that tell it what to become," says Cayetano González, whose group began the project at EMBL and has continued the work as they moved to the IRBB-PCB. "The current study investigates what happens when the process of localizing these molecules is disturbed."

Whether Prospero and its partners get to the right place depends on the activity of specific genes in the stem cell. EMBL PhD student Emmanuel Caussinus from González’s group created neuroblasts in which these genes were disrupted. "We no longer had normal neuroblasts and daughter cells capable of becoming part of a nerve," Caussinus says. "Instead, we had a tumor."

When these altered cells were transplanted into flies, the results were swift and dramatic. The tissue containing the altered cells grew to 100 times its initial size; cells invaded other tissues, and death followed. The growing tumor became "immortal", Caussinus says; cells could be retransplanted into new hosts for years, generation after generation, with similar effects.

The study proves that specific genes in stem cells - those which control the fates of daughter cells - are crucial. If such genes are disrupted, the new cells may no longer be able to control their reproduction, and this could lead to cancer. "It puts the focus on the events that create asymmetrical collections of molecules inside stem cells," González says. "This suggests new lines of investigation into the relationship between stem cells and tumors in other model organisms and humans."

Sarah Sherwood | EMBL
Further information:
http://www.embl.de

More articles from Life Sciences:

nachricht Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden

nachricht The pyrenoid is a carbon-fixing liquid droplet
22.09.2017 | Max-Planck-Institut für Biochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>