Featured Research

from universities, journals, and other organizations

New idea for targeting a common cancer protein

Date:
October 20, 2013
Source:
American Association for Cancer Research
Summary:
Patients with cancers driven by the protein KRAS, which are particularly hard to treat, may benefit from small molecules that attach to and disrupt the function of a KRAS-containing protein complex.

Patients with cancers driven by the protein KRAS, which are particularly hard to treat, may benefit from small molecules that attach to and disrupt the function of a KRAS-containing protein complex, according to results presented here at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics, held Oct. 19-23.

Mutant forms of the protein KRAS are found in approximately 30 percent of all cancers. They are responsible for many of the hallmarks of these cancers, and KRAS is, therefore, considered an important therapeutic target. However, attempts to develop clinically useful KRAS-targeted drugs have been unsuccessful.

"KRAS is a molecular switch," said Michael Burns, a doctor of medicine and doctor of philosophy candidate at Vanderbilt School of Medicine in Nashville, Tenn. "In the 'on' state it transmits signals that drive cell growth and survival. In many cancers, KRAS is permanently in the on state, and it is a highly validated therapeutic target.

"KRAS switches from off to on most efficiently when it is attached to a protein called SOS," explained Burns. "Each SOS protein attaches to two KRAS proteins, and we have identified a number of small molecules that bind to a particular part of SOS when it is in a complex with two KRAS proteins. These small molecules disrupt the function of the complex, ultimately causing inhibition of the signaling pathways downstream of KRAS that drive cell growth and survival. Although our data were generated in biochemical assays and cell lines, they suggest a potential way to therapeutically target KRAS, which has not been possible to date."

KRAS switches from off to on during a process called guanine nucleotide exchange, and SOS increases the rate at which this process occurs. Burns and colleagues hypothesized that small molecules that blocked SOS-mediated guanine nucleotide exchange would prevent KRAS switching on and, therefore, inhibit the signaling pathways downstream of KRAS that drive cell growth and survival.

Instead, they found that a number of small molecules that attached to a special pocket in a region of SOS called the CDC25 domain and increased SOS-mediated guanine nucleotide exchange actually inhibited two of the major signaling pathways downstream of KRAS: the MAPK and PI3K signaling pathways.

The researchers are actively investigating why small molecules that increased SOS-mediated guanine nucleotide exchange in biochemical assays blocked signaling downstream of KRAS in cell lines. They are also working to optimize the small molecules before they conduct studies in preclinical models of cancer.


Story Source:

The above story is based on materials provided by American Association for Cancer Research. Note: Materials may be edited for content and length.


Cite This Page:

American Association for Cancer Research. "New idea for targeting a common cancer protein." ScienceDaily. ScienceDaily, 20 October 2013. <www.sciencedaily.com/releases/2013/10/131020160642.htm>.
American Association for Cancer Research. (2013, October 20). New idea for targeting a common cancer protein. ScienceDaily. Retrieved September 23, 2014 from www.sciencedaily.com/releases/2013/10/131020160642.htm
American Association for Cancer Research. "New idea for targeting a common cancer protein." ScienceDaily. www.sciencedaily.com/releases/2013/10/131020160642.htm (accessed September 23, 2014).

Share This



More Health & Medicine News

Tuesday, September 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Liberia Pleads for Help to Fight Ebola

Liberia Pleads for Help to Fight Ebola

AP (Sep. 22, 2014) Liberia's finance minister is urging the international community to quickly follow through on pledges of cash to battle Ebola. Bodies are piling up in the capital Monrovia as the nation awaits more help. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Ebola Doctor Says Border Controls Critical

Ebola Doctor Says Border Controls Critical

AP (Sep. 22, 2014) A Florida doctor who helped fight the expanding Ebola outbreak in West Africa says the disease can be stopped, but only if nations quickly step up their response and make border control a priority. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Global Ebola Aid Increasing But Critics Say It's Late

Global Ebola Aid Increasing But Critics Say It's Late

Newsy (Sep. 21, 2014) More than 100 tons of medical supplies were sent to West Africa on Saturday, but aid workers say the global response is still sluggish. Video provided by Newsy
Powered by NewsLook.com
Sierra Leone in Lockdown to Control Ebola

Sierra Leone in Lockdown to Control Ebola

AP (Sep. 21, 2014) Sierra Leone residents remained in lockdown on Saturday as part of a massive effort to confine millions of people to their homes in a bid to stem the biggest Ebola outbreak in history. (Sept. 20) Video provided by AP
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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