Featured Research

from universities, journals, and other organizations

Enzyme may drive breast cancer growth

Date:
May 20, 2011
Source:
University of Illinois at Chicago
Summary:
A recently discovered enzyme drives the production of a potent form of estrogen in human breast cancer tissue, according to new research.

A recently discovered enzyme drives the production of a potent form of estrogen in human breast cancer tissue, researchers from the University of Illinois at Chicago College of Medicine have found.

Related Articles


The extra-strength estrogen, called estradiol, then drives the production of even more enzyme, in what may be a lethal feed-forward mechanism. Estradiol has been implicated in exacerbating tumor growth in breast cancer.

The research is published in the May issue of the journal Molecular Endocrinology.

Scientists had observed the increased production of an unknown protein in ovarian tissue in response to estrogen. UIC researchers under the direction of Geula Gibori, UIC professor of physiology and biophysics, then purified the protein and cloned its gene. Several laboratories established that it is an enzyme that converts a weak estrogen, estrone, to the much more potent estradiol.

The UIC researchers then examined the production of the enzyme in a line of breast cancer cells known to respond to estrogen levels.

"Estradiol up-regulates the very enzyme that produces estradiol, creating a positive cycle where this potent form of estrogen is being produced over and over again, sustaining its own production," said Aurora Shehu, UIC postdoctoral research associate in physiology and biophysics and first author of the study.

In human breast tissue, the researchers found a "dramatic" up-regulation in the cancerous cells but not in the surrounding benign tissue, said Gibori, who is principal investigator on the study. The surrounding tissue, however, is a rich source of the estrone that the enzyme needs to produce more estradiol, she said.

The researchers were able to show how estradiol turns on the gene that produces the enzyme, and that this activation also required at least one other known regulatory factor.

They found that tamoxifen, a drug widely used to inhibit breast cancer growth, prevents estradiol's stimulation of the enzyme and thus may shut down local production of estradiol in breast cancer cells.

"Breast cancer tumors with this enzyme are likely to be a much more aggressive and potentially deadly type of cancer," Gibori said. "Identifying this enzyme and how its expression is turned on gives medical researchers potential targets for disrupting the lethal production of estradiol in breast cancers."

The enzyme is a promising therapeutic target because blocking it may halt production only of the dangerous estradiol, which would reduce the side effects seen with other drugs that inhibit production of many estrogen-related compounds, Gibori said.

This study was supported by grants from the National Institutes of Health. Y. Sangeeta Devi, Kristin Luther, Julia Halpern, Jamie Le, Jifang Mao, Rachel Duan and Jonna Frasor from UIC and Constance Albarracin of the University of Texas, Houston, also contributed to the study.


Story Source:

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


Journal Reference:

  1. A. Shehu, C. Albarracin, Y. S. Devi, K. Luther, J. Halperin, J. Le, J. Mao, R. W. Duan, J. Frasor, G. Gibori. The Stimulation of HSD17B7 Expression by Estradiol Provides a Powerful Feed-Forward Mechanism for Estradiol Biosynthesis in Breast Cancer Cells. Molecular Endocrinology, 2011; 25 (5): 754 DOI: 10.1210/me.2010-0261

Cite This Page:

University of Illinois at Chicago. "Enzyme may drive breast cancer growth." ScienceDaily. ScienceDaily, 20 May 2011. <www.sciencedaily.com/releases/2011/05/110518161711.htm>.
University of Illinois at Chicago. (2011, May 20). Enzyme may drive breast cancer growth. ScienceDaily. Retrieved December 19, 2014 from www.sciencedaily.com/releases/2011/05/110518161711.htm
University of Illinois at Chicago. "Enzyme may drive breast cancer growth." ScienceDaily. www.sciencedaily.com/releases/2011/05/110518161711.htm (accessed December 19, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Friday, December 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Kids Die While Under Protective Services

Kids Die While Under Protective Services

AP (Dec. 18, 2014) As part of a six-month investigation of child maltreatment deaths, the AP found that hundreds of deaths from horrific abuse and neglect could have been prevented. AP's Haven Daley reports. (Dec. 18) Video provided by AP
Powered by NewsLook.com
Dads-To-Be Also Experience Hormone Changes During Pregnancy

Dads-To-Be Also Experience Hormone Changes During Pregnancy

Newsy (Dec. 18, 2014) A study from University of Michigan researchers found that expectant fathers see a decrease in testosterone as the baby's birth draws near. Video provided by Newsy
Powered by NewsLook.com
Prenatal Exposure To Pollution Might Increase Autism Risk

Prenatal Exposure To Pollution Might Increase Autism Risk

Newsy (Dec. 18, 2014) Harvard researchers found children whose mothers were exposed to high pollution levels in the third trimester were twice as likely to develop autism. Video provided by Newsy
Powered by NewsLook.com
UN: Up to One Million Facing Hunger in Ebola-Hit Countries

UN: Up to One Million Facing Hunger in Ebola-Hit Countries

AFP (Dec. 17, 2014) Border closures, quarantines and crop losses in West African nations battling the Ebola virus could lead to as many as one million people going hungry, UN food agencies said on Wednesday. Duration: 00:52 Video provided by AFP
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