Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

MIT sheds light on how tumor cells form

21.06.2006
MIT cancer researchers have discovered a process that may explain how some tumor cells form, a discovery that could one day lead to new therapies that prevent defective cells from growing and spreading.

The work was reported June 8 in the advance online issue of The EMBO Journal, a publication of the European Molecular Biology Organization (EMBO).

Tumor cells that grow aggressively often have an irregular number of chromosomes, the structures in cells that carry genetic information. The normal number of chromosomes in a human cell is 46, or 23 pairs. Aggressive tumor cells often have fewer or more than 23 pairs of chromosomes, a condition called aneuploidy.

To date it has not been clear how tumor cells become aneuploid.

"Checkpoint proteins" within cells work to prevent cells from dividing with an abnormal number of chromosomes, but scientists have been puzzled by evidence that aneuploidy can result even when these proteins appear to be normal.

What MIT researchers have discovered is a reason these checkpoint proteins may be unable to sense the defective cells, which tend to have very subtle errors in them. (These subtle errors are believed to be the cause of aneuploidy and the rapid growth of tumors.)

Before cells divide, individual chromosomes in each pair of chromosomes must attach to a set of tiny structures called microtubules. If they attach correctly, the checkpoint proteins give them the go-ahead to divide. If they don't, the checkpoint proteins are supposed to stop them from dividing.

"The checkpoint proteins are like referees in a tug-of-war contest," said Viji Draviam, a research scientist in MIT's Department of Biology and lead author of the paper. "They make sure that all chromosomes are lined up in the right places before the cell is allowed to divide."

Scientists have known about the function of checkpoint proteins for at least 20 years, and they have suspected that mutations in checkpoint proteins cause the irregular number of chromosomes in the aneuploid cells. But they have been perplexed by the infrequent occurrence of mutations in aneuploid tumors.

"It's puzzling that the suspected culprits - the aneuploidy-inducing checkpoint mutations - are rarely found at the scene of the crime, in the aneuploid tumors," Draviam said.

That lingering question prompted Draviam and her colleagues to study how two other key molecules - a known tumor suppressor protein called APC and its partner protein EB1 - work together to assure that cells divide normally.

They discovered that if they removed either protein from a cell or if they interrupted the way the proteins work together, the cell would become aneuploid. In other words, the checkpoint proteins need to sense that the APC and EB1 proteins both are present for normal cell division to take place.

"This is important because it is the first demonstration that interrupting the normal function of these proteins will cause the cell to become aneuploid," Draviam said. "Our research sheds light on what could go wrong to cause an irregular number of chromosomes in cells even when the checkpoint proteins appear to be functioning properly."

Draviam's co-authors are graduate students Irina Shapiro and Bree Aldridge and MIT Professor of Biology and Biological Engineering Peter Sorger.

The research was funded by the National Institutes of Health.

Elizabeth A. Thomson | MIT News Office
Further information:
http://www.mit.edu

More articles from Life Sciences:

nachricht The balancing act: An enzyme that links endocytosis to membrane recycling
07.12.2016 | National Centre for Biological Sciences

nachricht Transforming plant cells from generalists to specialists
07.12.2016 | Duke 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: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

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,...

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

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

How to turn white fat brown

07.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>