Featured Research

from universities, journals, and other organizations

Stem Cell Marker Controls Two Key Cancer Pathways

Date:
April 16, 2008
Source:
Georgetown University Medical Center
Summary:
Researchers have discovered that a gene associated with human breast stem cells can stimulate development of mammary cells by activating two critical cancer pathways. This finding provides new evidence that breast cancer can arise from stem cells and that targeting this gene might provide a new way to treat cancers of the breast as well as other tumor types.

Researchers at Georgetown University Medical Center have discovered that a gene associated with human breast stem cells can stimulate development of mammary cells by activating two critical cancer pathways. They say this finding, reported at the annual meeting of the American Association for Cancer Research (AACR), provides new evidence that breast cancer can arise from stem cells and that targeting this gene might provide a new way to treat cancers of the breast as well as other tumor types.

"This is the first time any role has been attributed to this gene, and it turns out to be one that is surprisingly powerful," says the study's lead author, Xiaoyang Wang, Ph.D., Postdoctoral Fellow at Georgetown's Lombardi Comprehensive Cancer Center.

Specifically, Wang and the researchers show for the first time that this gene, Musashi1 (Msi1), switches on Wnt and Notch cell signaling. Both of these pathways help control stem cell growth, and are known to be critically important to the development of many cancers.

Msi1 was named after a famous 17th century Japanese swordsman, Miyamoto Musashi, by Japanese researcher Hideyuki Okano, Ph.D., who identified it in fruit flies in 1994. Okano currently collaborates with the Georgetown scientists.

Recent studies have shown Msi1 to be a marker of human stem cells in general because it has been found in human breast, colon, brain, skin, and other cells, says Robert Glazer, Ph.D., a professor of Oncology and Pharmacology and the study's senior author.

So Glazer and Wang decided to probe the gene's function. "Msi1 is known to be a marker of stem cells, but no one knows what it does. We wanted to see if it had a function in the mammary gland," Glazer says.

They were especially interested in whether Msi1 is associated with cancer development because recent studies have suggested that stem cells may be the causative root of some cancers -- a notion that is vigorously debated among cancer researchers.

"It is really critical to understand if stem cells are involved in cancer development because a lot of therapies used to treat cancer don't target stem cells," he says. "That may explain why tumors come back."

In laboratory experiments, the scientists found that, in mammary cell development, Msi1 drives mammary cells along different lineages -- in other words, it can decide what type of cell develops in the breast, be it muscle cells or cells that line milk ducts, etc.

In cancer, the Wnt and Notch pathways are often activated, and the researchers found that Msi1 is expressed in particularly aggressive tumors. The researchers then tested whether Msi1 regulates these pathways in mammary cells and found that it did.

The researchers then studied how Msi1 drives the Wnt and Notch pathways found that when Msi1 was over-expressed, there was an increased secretion of a growth factor known as proliferin, and reduced secretion of the Wnt pathway inhibitor, Dickkopf-3. Additionally, Msi1 programmed the expression of a number of genes that have a concerted effect on the cell cycle, Wang says.

"We believe that while Msi1 may contribute to cell proliferation, it is not the single gene that controls cancer development," Glazer says.

"This work suggests, but does not prove, that stem cells drive breast cancer formation," he says. "Msi1 might make a good therapeutic target, and we are currently testing ways to interfere with its function in cells to see if it disrupts cancer cell proliferation."

The study was funded by the Charlotte Geyer Foundation and the National Institutes of Health.

Other study contributors include Yuzhi Yin, M.D., Ph.D. and Hongyan Yuan, M.D., both of the Department of Oncology, Georgetown University, Toshiyuki Sakamaki, Ph.D., Niigata University, Niigata, Japan and Hideyuki Okano, Ph.D., Keio University, Keio, Japan.


Story Source:

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


Cite This Page:

Georgetown University Medical Center. "Stem Cell Marker Controls Two Key Cancer Pathways." ScienceDaily. ScienceDaily, 16 April 2008. <www.sciencedaily.com/releases/2008/04/080414113212.htm>.
Georgetown University Medical Center. (2008, April 16). Stem Cell Marker Controls Two Key Cancer Pathways. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2008/04/080414113212.htm
Georgetown University Medical Center. "Stem Cell Marker Controls Two Key Cancer Pathways." ScienceDaily. www.sciencedaily.com/releases/2008/04/080414113212.htm (accessed October 22, 2014).

Share This



More Health & Medicine News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

CDC Revamps Ebola Guidelines After Criticism

CDC Revamps Ebola Guidelines After Criticism

Newsy (Oct. 21, 2014) The Centers for Disease Control and Prevention have issued new protocols for healthcare workers interacting with Ebola patients. Video provided by Newsy
Powered by NewsLook.com
WHO: Ebola Vaccine Trials to Start a in January

WHO: Ebola Vaccine Trials to Start a in January

AP (Oct. 21, 2014) Tens of thousands of doses of experimental Ebola vaccines could be available for "real-world" testing in West Africa as soon as January as long as they are deemed safe in soon to start trials, the World Health Organization said Tuesday. (Oct. 21) Video provided by AP
Powered by NewsLook.com
First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

Newsy (Oct. 21, 2014) A medical team has for the first time given a man the ability to walk again after transplanting cells from his brain onto his severed spinal cord. Video provided by Newsy
Powered by NewsLook.com
CDC Issues New Ebola Guidelines for Health Workers

CDC Issues New Ebola Guidelines for Health Workers

Reuters - US Online Video (Oct. 21, 2014) The U.S. Centers for Disease Control and Prevention has set up new guidelines for health workers taking care of patients infected with Ebola. Linda So reports. Video provided by Reuters
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