Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


MIT sheds light on how tumor cells form

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:

More articles from Life Sciences:

nachricht ‘Farming’ bacteria to boost growth in the oceans
24.10.2016 | Max-Planck-Institut für marine Mikrobiologie

nachricht Calcium Induces Chronic Lung Infections
24.10.2016 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

All Focus news of the innovation-report >>>



Event News

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

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Oasis of life in the ice-covered central Arctic

24.10.2016 | Earth Sciences

‘Farming’ bacteria to boost growth in the oceans

24.10.2016 | Life Sciences

Light-driven atomic rotations excite magnetic waves

24.10.2016 | Physics and Astronomy

More VideoLinks >>>