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: firstname.lastname@example.org.
Diana Yates | University of Illinois
Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory
Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine