Featured Research

from universities, journals, and other organizations

Breast Cancer Can Be Reversed In Laboratory Mice, Scientists Report

Date:
November 3, 2003
Source:
University Of California, Davis - Medical Center
Summary:
Breast cancer researchers have demonstrated for the first time that it is possible to block genetic switches in mice that turn cancer on and off -- thus preventing and even reversing breast cancer in the animals. The findings, reported Sunday morning at the 24th Congress of the International Association for Breast Cancer Research, suggest potential new molecular targets for drugs to prevent and potentially eradicate breast cancer in humans.

SACRAMENTO, Calif. -- Breast cancer researchers have demonstrated for the first time that it is possible to block genetic switches in mice that turn cancer on and off -- thus preventing and even reversing breast cancer in the animals. The findings, reported Sunday morning at the 24th Congress of the International Association for Breast Cancer Research, suggest potential new molecular targets for drugs to prevent and potentially eradicate breast cancer in humans.

"It's enormously gratifying," said conference director Robert Cardiff, professor of pathology at UC Davis School of Medicine and Medical Center and an author of the research. "Our findings suggest paths forward that may help us alter the biological path of breast cancer and more successfully treat -- and even potentially prevent -- this cancer in humans."

In new research reported by a team of scientists from Canada, Switzerland and UC Davis, investigators demonstrated that removing a single gene known as beta-1 integrin prevented or halted breast cancer growth in laboratory mice. Beta-1 integrin is a principal regulator of normal breast tissue growth and survival, but if the gene malfunctions, it can directly initiate breast tumors. The new work demonstrates that knocking out the beta-1 integrin gene prevents cancer-prone mice from developing breast tumors, and halts further tumor growth in mice that have already developed breast cancer.

"This study shows that it is absolutely essential to have the beta-1 integrin gene present in order for mammary gland tumors to develop. We now have a good target for biological drug development, and the challenge is to develop an agent that can block its activity," said William J. Muller, professor of biochemistry at McGill University in Montreal and a lead investigator of the study.

In a related presentation, researchers from the University of Pennsylvania reported on a series of experiments using a novel mouse model of human breast cancer, one that enables scientists to turn oncogenes -- genes that can cause cancer -- on or off at will. A triggering agent, in this case the antibiotic doxycycline, throws the switch on or off. Scientists used the approach to test four oncogenes: c-myc, Neu, Wnt1, and v-Ha-Ras. When any one of the oncogenes was turned on, the transgenic mice developed extremely aggressive mammary tumors; in many cases, the tumors metastasized to the lungs. When the gene was turned off, many of the breast tumors -- including many of the most aggressive and advanced cancers -- regressed to the point that they no longer could be detected by physical examination, magnetic resonance imaging (MRI) or positron emission tomography (PET) scans.

"We're extremely encouraged that we have been able to demonstrate in laboratory animals that we can make mammary cancers essentially disappear by reversing just one mutation," said Lewis A. Chodosh, associate professor at the Abramson Family Cancer Research Center at the University of Pennsylvania and lead author of the study.

"This suggests that, with appropriate therapies that target the genes used in this study, we might be able to cause tumors to regress and improve substantially, even those that are quite advanced."

However, even though many of the tumors in the transgenic mice went into complete remission, a substantial number of the cancers spontaneously recurred over periods of up to a year, Chodosh reported.

This finding is important since it replicates the natural history of human breast cancer -- many women, after apparently successful treatment, harbor residual tumor cells that eventually give rise to tumor recurrences that ultimately may result in death. Some of these residual cells can remain for decades. No previous laboratory mouse model has successfully replicated this feature of human breast cancer cells.

"The next critical step is to figure out the mechanisms that some tumors use to escape these treatments," Chodosh said. "We believe these mouse models will help us to do exactly that."

###

Founded in the mid 1950s, the International Association for Breast Cancer Research is an international community of scientists focused on the important issues in modern breast cancer research. The 24th IABCR Congress, focused on preclinical research using mouse models of human breast cancer, is sponsored by UC Davis Cancer Center, the Office of Women's Health of the U.S. Department of Health and Human Services, the California Breast Cancer Research Program, and the National Cancer Institute's Mouse Models of Human Cancers Consortium and Specialized Programs of Research Excellence.

For more information about the meeting, visit the conference Web site at http://cme.ucdmc.ucdavis.edu/iabcr.htm.


Story Source:

The above story is based on materials provided by University Of California, Davis - Medical Center. Note: Materials may be edited for content and length.


Cite This Page:

University Of California, Davis - Medical Center. "Breast Cancer Can Be Reversed In Laboratory Mice, Scientists Report." ScienceDaily. ScienceDaily, 3 November 2003. <www.sciencedaily.com/releases/2003/11/031103065738.htm>.
University Of California, Davis - Medical Center. (2003, November 3). Breast Cancer Can Be Reversed In Laboratory Mice, Scientists Report. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2003/11/031103065738.htm
University Of California, Davis - Medical Center. "Breast Cancer Can Be Reversed In Laboratory Mice, Scientists Report." ScienceDaily. www.sciencedaily.com/releases/2003/11/031103065738.htm (accessed July 29, 2014).

Share This




More Health & Medicine News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Ebola Virus Threatens West Africa

Deadly Ebola Virus Threatens West Africa

AP (July 28, 2014) West African nations and international health organizations are working to contain the largest Ebola outbreak in history. It's one of the deadliest diseases known to man, but the CDC says it's unlikely to spread in the U.S. (July 28) Video provided by AP
Powered by NewsLook.com
$15B Deal on Vets' Health Care Reached

$15B Deal on Vets' Health Care Reached

AP (July 28, 2014) A bipartisan deal to improve veterans health care would authorize at least $15 billion in emergency spending to fix a veterans program scandalized by long patient wait times and falsified records. (July 28) Video provided by AP
Powered by NewsLook.com
Two Americans Contract Ebola in Liberia

Two Americans Contract Ebola in Liberia

Reuters - US Online Video (July 28, 2014) Two American aid workers in Liberia test positive for Ebola while working to combat the deadliest outbreak of the virus ever. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) 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:
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