Featured Research

from universities, journals, and other organizations

A Sweet Step Toward New Cancer Therapies

Date:
March 31, 2007
Source:
University of Michigan
Summary:
By recognizing sugars, a technique developed by University of Michigan analytical chemist Kristina Hakansson sets the stage for new cancer diagnosis and treatment options.

By recognizing sugars, a technique developed by University of Michigan analytical chemist Kristina Hakansson sets the stage for new cancer diagnosis and treatment options.

A growing body of evidence points to assemblies of sugars called glycans attached to proteins on cancer cell surfaces as accomplices in the growth and spread of tumors. Researchers have been keen to characterize these glycans, but traditional analytical methods have not been sufficient.

Now, Hakansson's research group has demonstrated that their technique can be used to identify and structurally characterize glycans. Their work is described in the April 15 issue of the journal Analytical Chemistry.

Typically, analytical chemists use mass spectrometry—a technique that accurately weighs molecules or fragments of molecules—to analyze proteins. In this process, proteins are introduced into the mass spectrometer and fragmented by heating until the weakest bonds break. "It's the 'shake-it-til-it-breaks' approach," Hakansson said.

Together, the masses of the various fragments provide a sort of fingerprint that reveals the genetic blueprint from which the protein was built—information that helps researchers confirm the protein's identity. This works fine as long as the protein has not been modified after it was produced. But if other chemical groups such as phosphates, sulfates or sugars have been added, the identification method breaks down.

"If sugars are attached, for instance, the weakest bonds are not the bonds that hold the protein together; they're the bonds between the sugars," Hakansson said. When those bonds break, the resulting fragments don't give accurate information about either the protein's identity or the exact type and position of sugars present.

To get around that problem, researchers have used a process called electron capture dissociation (ECD) instead of the usual "shake-it-til-it breaks" method to fragment proteins. But that method requires the presence of at least two positive charges, which can be difficult to accomplish with acidic molecules, such as proteins with sulfate or phosphate groups attached.

Hakansson's group has been exploring the use of metals such as calcium and iron to carry the necessary positive charges. In a series of recently published papers, they first showed that their method can be used to selectively cleave different bonds and then demonstrated that it can be used to identify sulfate-laden proteins and to pinpoint the location of the sulfate groups on them.

In the latest research, they extended the technique to sugars, an even more challenging task.

"Sugars are not like other biomolecules," Hakansson said. "They're linked rings with lots of branches, like trees. If you cut off a branch, you don't know which part of the tree it came from." The trick is to make breaks that cut across the ring structures, rather lopping off branches. By using metals as charge carriers, the researchers were able to do just that, yielding valuable structural information.

In a project that continues to build on this line of work, Hakansson is collaborating with U-M Health System cancer surgeon Diane Simeone to investigate sugars attached to proteins in the membranes of pancreatic cancer cells.

"The work is in very early stages, but we hope that by measuring unique sugars it may be possible to develop diagnostic tools or therapeutic agents to specifically target them," Hakansson said.


Story Source:

The above story is based on materials provided by University of Michigan. Note: Materials may be edited for content and length.


Cite This Page:

University of Michigan. "A Sweet Step Toward New Cancer Therapies." ScienceDaily. ScienceDaily, 31 March 2007. <www.sciencedaily.com/releases/2007/03/070330184917.htm>.
University of Michigan. (2007, March 31). A Sweet Step Toward New Cancer Therapies. ScienceDaily. Retrieved September 18, 2014 from www.sciencedaily.com/releases/2007/03/070330184917.htm
University of Michigan. "A Sweet Step Toward New Cancer Therapies." ScienceDaily. www.sciencedaily.com/releases/2007/03/070330184917.htm (accessed September 18, 2014).

Share This



More Matter & Energy News

Thursday, September 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Stocks Hit All-Time High as Fed Holds Steady

Stocks Hit All-Time High as Fed Holds Steady

AP (Sep. 17, 2014) The Federal Reserve signaled Wednesday that it plans to keep a key interest rate at a record low because a broad range of U.S. economic measures remain subpar. Stocks hit an all-time high on the news. (Sept. 17) Video provided by AP
Powered by NewsLook.com
Space Race Pits Bezos Vs Musk

Space Race Pits Bezos Vs Musk

Reuters - Business Video Online (Sep. 16, 2014) Amazon CEO Jeff Bezos' startup will team up with Boeing and Lockheed to develop rocket engines as Elon Musk races to have his rockets certified. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
MIT's Robot Cheetah Unleashed — Can Now Run, Jump Freely

MIT's Robot Cheetah Unleashed — Can Now Run, Jump Freely

Newsy (Sep. 16, 2014) MIT developed a robot modeled after a cheetah. It can run up to speeds of 10 mph, though researchers estimate it will eventually reach 30 mph. Video provided by Newsy
Powered by NewsLook.com
Manufacturer Prints 3-D Car In Record Time

Manufacturer Prints 3-D Car In Record Time

Newsy (Sep. 15, 2014) Automobile manufacturer Local Motors created a drivable electric car using a 3-D printer. Printing the body only took 44 hours. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins