Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Soy processing influences estrogen-dependent breast cancer growth in mice

07.05.2004


Highly purified soy foods and soy supplements marketed in the United States may stimulate the growth of pre-existing estrogen-dependent breast tumors, according to a study done at the University of Illinois at Urbana-Champaign.



"Soy has been correlated with low rates of breast cancer in Asian populations, but soy foods in Asia are made from minimally processed soybeans or defatted, toasted soy flour, which is quite different from soy products consumed in the U.S.," said William G. Helferich, a professor of food science and human nutrition, in a study presented online May 6 in advance of regular publication by the journal Carcinogenesis.

"Isoflavone-containing products consumed in the U.S. may have lost many of the biologically active components in soy, and these partially purified isoflavone-containing products may not have the same health benefits as whole soy foods," he said.


Soy isoflavone products are marketed as dietary estrogens to women over age 50 as a natural alternative to hormone replacement therapy (HRT), but this is the age group in which most breast cancers occur.

Seventy-five percent of breast cancer cases are diagnosed in women over 50, and the majority of these cases are estrogen-dependent. For these women, Helferich said, consumption of highly processed isoflavone products may pose a risk.

Helferich used an animal model that has been used extensively to evaluate breast cancer therapies such as tamoxifen. "The results of this preclinical investigation are especially relevant to postmenopausal women with estrogen-responsive breast cancers who are looking for alternatives to HRT," he said.

In the study, mice were fed equal concentrations of the soy isoflavone genistein, allowing Helferich to determine the influences that various bioactive soy compounds had on genistein’s ability to stimulate estrogen-dependent breast tumor growth. "As bioactive compounds were removed, we observed an increase in estrogen-dependent tumor growth," he said.

If genistein had been the only biologically active compound, all diets would have resulted in similar tumor growth, but that was not the case, he said.

A soy flour and mixed isoflavones diet and a mixed isoflavone diet each contained equal amounts of genistein, but differed in the amount of other bioactive components originally present in the soy flour. Tumors neither grew nor regressed in animals fed these diets. "The minimally processed soy flour used in these diets is more like the soy foods in the Asian diet," Helferich said.

"Dietary soy products that contained isoflavones in more purified forms were associated with greater tumor growth. These products are similar to the materials used in isoflavone-containing dietary supplements, which is how many Americans consume these compounds," he added.

Other researchers contributing to the study were Clinton D. Allred, Kimberly F. Allred, Young H. Ju, Tracy S. Goeppinger, and Daniel R. Doerge.


The study was funded by grants from the National Institutes of Health and USDA.

Phyllis Picklesimer | EurekAlert!
Further information:
http://www.uiuc.edu/

More articles from Studies and Analyses:

nachricht Study relating to materials testing Detecting damages in non-magnetic steel through magnetism
23.07.2018 | Technische Universität Kaiserslautern

nachricht Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>