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 Fine organic particles in the atmosphere are more often solid glass beads than liquid oil droplets
21.04.2017 | Max-Planck-Institut für Chemie

nachricht Study overturns seminal research about the developing nervous system
21.04.2017 | University of California - Los Angeles Health Sciences

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

Im Focus: Quantum-physical Model System

Computer-assisted methods aid Heidelberg physicists in reproducing experiment with ultracold atoms

Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...

Im Focus: Glacier bacteria’s contribution to carbon cycling

Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.

A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

New quantum liquid crystals may play role in future of computers

21.04.2017 | Physics and Astronomy

A promising target for kidney fibrosis

21.04.2017 | Health and Medicine

Light rays from a supernova bent by the curvature of space-time around a galaxy

21.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>