Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Estrogen interferes with immune surveillance in breast cancer

25.01.2007
Estrogen is known to enhance the growth and migration of breast cancer cells. Now researchers at the University of Illinois at Urbana-Champaign have found that estrogen also can shield breast cancer cells from immune cells.

In a study published online this week in Oncogene, the researchers report that estrogen induces the expression of an inhibitor that blocks immune cells’ ability to kill tumor cells. This is the first study to identify estrogen’s role in shielding breast cancer cells from the action of immune cells.

The researchers analyzed estrogen’s role in the cascade of events that occurs when immune cells, called natural killer cells, encounter a tumor cell. Under normal conditions, natural killer cells release granules that contain enzymes, called granzymes, which enter and kill the tumor cell.

The research team found that when estrogen binds to an estrogen receptor the complex promotes production of a granzyme inhibitor, proteinase inhibitor 9 (PI-9). The inhibitor binds the granzyme, preventing it from initiating the molecular cascade that kills tumor cells.

“It wasn’t known that estrogen could do this in breast cancer cells,” said principal investigator David J. Shapiro, a professor of biochemistry in the School of Molecular and Cellular Biology. “The amounts of estrogen required to do this are quite small.”

U. of I. graduate student Xinguo Jiang also found that when breast cancer cells that contain very high levels of estrogen receptor protein are exposed to low levels of estrogen, they produce large quantities of the granzyme inhibitor and become highly resistant to immune attack.

The researchers were able to show that estrogen’s effect on PI-9 production was the sole mechanism by which estrogen interfered with the natural killer cells’ ability to kill off breast cancer cells. They did so by blocking PI-9 production in the breast cancer cells exposed to estrogen. When these breast cancer cells were targeted by natural killer cells, they were efficiently killed off, even when significant levels of estrogen and estrogen receptor were present.

Estrogens are known to cause only a few types of cancers, Shapiro said. PI-9 also has been implicated in other cancers. High levels of PI-9 in some lymphomas, for example, are associated with poor prognoses.

This study demonstrates how basic research can have important and unanticipated implications for understanding diseases such as breast cancer, Shapiro said. The finding that estrogens stimulate PI-9 production could eventually help drug designers develop new tests – and targets – for breast cancer therapy.

The research team included collaborators from the University of Wisconsin at Madison.

Editor’s note: To reach David J. Shapiro, call 217-333-1788; e-mail: djshapir@uiuc.edu.

Diana Yates | University of Illinois
Further information:
http://www.uiuc.edu

Further reports about: Estrogen Granzyme Inhibitor PI-9 Shapiro breast cancer natural killer cells

More articles from Life Sciences:

nachricht Closing in on advanced prostate cancer
13.12.2017 | Institute for Research in Biomedicine (IRB Barcelona)

nachricht Visualizing single molecules in whole cells with a new spin
13.12.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

A whole-body approach to understanding chemosensory cells

13.12.2017 | Health and Medicine

Water without windows: Capturing water vapor inside an electron microscope

13.12.2017 | Physics and Astronomy

Cellular Self-Digestion Process Triggers Autoimmune Disease

13.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>