Women who are obese have a higher risk and a worse prognosis for breast cancer, but the reasons why remain unclear. A Cornell study published this month in Science Translational Medicine explains how obesity changes the consistency of breast tissue in ways that are similar to tumors, thereby promoting disease.
The study of mice and women shows obesity leads to a stiffening of a meshwork of material that surrounds fat cells in the breast, called the extracellular matrix, and these biomechanical changes create the right conditions for tumor growth.
The findings suggest clinicians may need to employ finer-scale imaging techniques in mammograms, especially for obese women, to detect a denser extracellular matrix. Also, the results should caution doctors against using certain fat cells from obese women in plastic and reconstructive breast surgeries, as these cells can promote recurring breast cancer.
"We all know that obesity is bad; the metabolism changes and hormones change, so when looking for links to breast cancer, researchers almost exclusively have focused on the biochemical changes happening. But what these findings show is that there are also biophysical changes that are important," said Claudia Fischbach, associate professor of biomedical engineering and the paper's senior author. Bo Ri Seo, a graduate student in Fischbach's lab, is the paper's first author.
The study is a collaboration between Cornell's Ithaca campus and researchers at Weill Cornell Medical College and includes Dr. Andrew Dannenberg, professor of medicine.
Fat tissue in obese women has more cells called myofibroblasts, compared with fat tissue in normal-weight women. Myofibroblasts are wound-healing cells that determine whether a scar will form. All cells secrete compounds to create an extracellular matrix, and they remodel and grab onto this meshwork to make tissue. But when myofibroblasts make an extracellular matrix, they pull together - the action needed to close a wound - stiffening the tissue.
But "these are cells in our body regardless of injury," said Fischbach. In obese women, there are more myofibroblasts than in lean women, which leads to scarring and stiffening without an injury in the extracellular matrix. Tumors also recruit more myofibroblasts than are found in healthy tissue, which also leads to stiffer extracellular matrix.
Many obese women get regular mammograms but signs of disease don't show up because detecting their dense extracellular matrix between the fat cells requires a finer-scale resolution. The findings "may inspire use of higher resolution imaging techniques to detect those changes," said Fischbach. "Right now, people don't look for stiffer extracellular matrices as a clinical biomarker."
During plastic or reconstructive surgery following mastectomy in breast cancer patients, doctors may inject adipose stromal cells from obese donors to regenerate tissue. "What our data suggests is that it is really important where these cells are being taken from," Fischbach said. "If you use these cells from an obese patient, they are very different and you may actually be driving malignancies if you implant them."
The study was funded by the National Institutes of Health, the National Science Foundation, the Breast Cancer Research Foundation and the Botwinick-Wolfensohn Foundation at WCMC.
Cornell University has television, ISDN and dedicated Skype/Google+ Hangout studios available for media interviews.
Melissa Osgood | EurekAlert!
Penn study identifies new malaria parasites in wild bonobos
21.11.2017 | University of Pennsylvania School of Medicine
NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures
17.11.2017 | National Institute of Standards and Technology (NIST)
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
21.11.2017 | Physics and Astronomy
21.11.2017 | Materials Sciences
21.11.2017 | Health and Medicine