Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Abnormal cell division explained

28.04.2005


Why do some cancer cells divide not into two, as cells are supposed to do in mitosis, but into three-four new cells that look thoroughly abnormal? This question was raised as early as the 1890s by the German tumor researcher David Hansemann, who could observe the strange mitosis even using the microscopes of his day. Now another David, Lund University researcher David Gisselsson, has found an answer.



Together with associates from the Section for Clinical Genetics, David Gisselsson has long been studying chromosome changes in various sorts of cancer cells. Contrary to the earlier belief that tumor cells are rather stable genetically, a few years ago he was able to show that genetic chaos prevails in certain severe cancer forms.

"The normal number of chromosomes in a human cell is 46. But in tumors from skeletal and pancreatic cancer, some cells can have far fewer than 46 chromosomes while others have several hundred. The structure of these chromosomes is also often abnormal-­for example, they have lost some parts, traded segments with each other, and copied certain genes in mass production," says David Gisselsson.


The Lund scientists have scrutinized these phenomena in a series of studies. They have been able to demonstrate that certain tumor cells get stuck in mitosis, so that their chromosomes do not divide neatly in two directions, but rather get pulled apart in a disorganized manner into the daughter cells. This is because the ends of the chromosomes, the so-called telomers, have lost their protective exteriors.

Cells with truncated, unprotected telomers from different chromosomes actually ought to simply die, but this does not happen in these tumor cells. Instead, the naked telomers cling to each other. This can be the explanation for the abnormal number of chromosomes in some tumor cells, where certain ones have incorporated a number of extra chromosomes while others wind up with too few.

Having the wrong number of chromosomes does not lead directly to death in these tumor cells. On the other hand, they have problems with mitosis.

"We have observed that these cells sometimes try to divide, but they fail and go into an idle state. If they then try again, they tend to divide in three or four directions. This explains Hansemann’s discovery from the 1890s!" says David Gisselsson.

In its latest study the Lund team has also shown that the daughter cells of those cells which divide in more than two directions have a completely random distribution of chromosomes. This genetic chaos is so great that the cells usually die.

Research groups in several countries have been studying von Hansemann mitosis at the molecular level, that is, what happens inside the cell. But this work has proven to have little relevance to the struggle against cancer. These are not the cells that make a tumor grow, since they themselves typically die off.

On the other hand, the Lund team now wishes to study substances that might be able to counteract cancer by further damaging already truncated telomers. In that way it may be possible to increase the genetic chaos in tumor cells in order to get more of them to simply die.

Ingela Björck | alfa
Further information:
http://www.lu.se

More articles from Life Sciences:

nachricht Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH

nachricht Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>