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 Researchers uncover protein-based “cancer signature”
05.12.2016 | Universität Basel

nachricht The Nagoya Protocol Creates Disadvantages for Many Countries when Applied to Microorganisms
05.12.2016 | Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

IHP presents the fastest silicon-based transistor in the world

05.12.2016 | Power and Electrical Engineering

InLight study: insights into chemical processes using light

05.12.2016 | Materials Sciences

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>