“People suggested that Runx3 might be a tumor suppressor in breast cancer because they found that it is down-regulated in a lot of breast cancer cell lines and breast cancer tissues,” said University of Illinois medical biochemistry professor Lin-Feng Chen, who led the study.
“We found mammary tumors growing in about 20 percent of the female mice lacking a copy of the Runx3 gene,” Chen said. None of the mice with two normal copies of the gene developed tumors.
The researchers also found that estrogen receptor alpha (ER-alpha), a well-known culprit in the development of many breast tumors, was up-regulated in the mouse tumors. ER-alpha is overexpressed in about 75 percent of human cases of breast cancer, and enhanced ER-alpha expression in normal breast tissue is associated with an increased risk of breast cancer, Chen said.
Circulating estrogen binds to ER-alpha and initiates a chain of events that alter gene expression in the targeted cell. This is a normal part of cellular signaling, but in ER-positive breast cancers, the overexpression of ER-alpha leads to enhanced tumor cell survival, growth and proliferation.
The researchers found that when Runx3 was re-introduced into ER-alpha positive breast cancer cell lines, it suppressed the growth of the cancer cells and inhibited the potential of the cancer cells to form tumors in the mouse. Further experiments revealed that Runx3 actually targeted ER-alpha signaling by inducing the degradation of ER-alpha.
“By regulating the cellular levels of ER-alpha, Runx3 appears to control the cell’s response to circulating estrogen, thus playing an important role in the onset of breast cancer,” Chen said.Chen sees three potential benefits that spring from this study. First, the researchers have discovered a mouse model of spontaneously occurring mammary tumors that corresponds to an age of increased risk of breast cancer in humans.
Second, Chen hopes to develop a simple test to measure Runx3 levels in mammary tissue.
“We know from other people’s studies that Runx3 is inactivated in the early stages of breast cancer,” he said. “So we might be able to use Runx3 as a biomarker of early stage breast cancer.”And third, since the Runx3 gene appears to be intact but inactivated in breast cancer, future studies will focus on reversing its inactivation, Chen said.
The National Institutes of Health and the U. of I. Campus Research Board funded this study.
The paper, “RUNX3 Acts as a Tumor Suppressor in Breast Cancer by Targeting Estrogen Receptor Alpha,” is available from the U. of I. News Bureau.
Diana Yates | University of Illinois
‘Farming’ bacteria to boost growth in the oceans
24.10.2016 | Max-Planck-Institut für marine Mikrobiologie
Calcium Induces Chronic Lung Infections
24.10.2016 | Universität Basel
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
24.10.2016 | Earth Sciences
24.10.2016 | Life Sciences
24.10.2016 | Physics and Astronomy