Their findings, which suggest that inflammation resulting from a molecule introduced through consumption of these foods could promote tumor growth, are published online this week in advance of print publication in the Proceedings of the National Academy of Sciences (PNAS).
Varki, UC San Diego School of Medicine distinguished professor of medicine and cellular and molecular medicine, and co-director of the UCSD Glycobiology Research and Training Center, and colleagues studied a non-human cellular molecule called N-glycolylneuraminic acid (Neu5Gc). Neu5Gc is a type of glycan, or sugar molecule, that humans don't naturally produce, but that can be incorporated into human tissues as a result of eating red meat. The body then develops anti-Neu5Gc antibodies – an immune response that could potentially lead to chronic inflammation, as first suggested in a 2003 PNAS paper by Varki.
"We've shown that tumor tissues contain much more Neu5Gc than is usually found in normal human tissues," said Varki. "We therefore surmised that Neu5Gc must somehow benefit tumors."
It has been recognized by scientists for some time that chronic inflammation can actually stimulate cancer, Varki explained. So the researchers wondered if this was why tumors containing the non-human molecule grew even in the presence of Neu5Gc antibodies.
"The paradox of Neu5Gc accumulating in human tumors in the face of circulating antibodies suggested that a low-grade, chronic inflammation actually facilitated the tumor growth, so we set out to study that hypothesis," said co-author Nissi M.Varki, M.D., UCSD professor of pathology.
Using specially bred mouse models that lacked the Neu5Gc molecule – mimicking humans before the molecule is absorbed into the body through ingesting red meat – the researchers induced tumors containing Neu5Gc, and then administered anti-Neu5Gc antibodies to half of the mice. In mice that were given antibodies inflammation was induced, and the tumors grew faster. In the control mice that were not treated with antibodies, the tumors were less aggressive
Others have previously shown that humans who take non-steroidal anti-inflammatory drugs (commonly known as NSAIDs) have a reduced risk of cancer. Therefore, the mice with cancerous tumors facilitated by anti-Neu5Gc antibodies were treated with an NSAID. In these animals, the anti-inflammatory treatment blocked the effect of the Neu5Gc antibodies and the tumors were reduced in size.
"Taken together, our data indicate that chronic inflammation results from interaction of Neu5Gc accumulated in our bodies from eating red meat with the antibodies that circulate as an immune response to this non-human molecule – and this may contribute to cancer risk," said Varki.
Debra Kain | EurekAlert!
Penn vet research identifies new target for taming Ebola
12.01.2017 | University of Pennsylvania
The strange double life of Dab2
10.01.2017 | University of Miami Miller School of Medicine
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).
Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...
Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.
The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...
UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration
"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...
10.01.2017 | Event News
09.01.2017 | Event News
05.01.2017 | Event News
17.01.2017 | Earth Sciences
17.01.2017 | Machine Engineering
17.01.2017 | Physics and Astronomy