Researchers with the University of California, San Diego, have reportedly linked a sugar molecule found in red meat to the development of spontaneous cancers. Annie N. Samraj, et al., “A red meat-derived glycan promotes inflammation and cancer progression,” Proceedings of the National Academy of Sciences, January 2015. According to a December 29, 2014, press release, N-glycolylneuraminic acid (Neu5Gc) is present in most mammals but not humans, who consume bioavailable forms of the molecule from beef, pork and lamb.

Building on previous work hypothesizing that Neu5Gc can cause chronic inflammation when absorbed by the human body, the study authors fed the sugar molecule to mice genetically engineered to suppress Neu5Gc. The results not only showed that these mice developed antibodies to Neu5Gc that contributed to systemic inflammation, but that the incidence of spontaneous tumor formation increased fivefold, with Neu5Gc accumulating in the tumors.

“Until now, all of our evidence linking Neu5Gc to cancer was circumstantial or indirectly predicted from somewhat artificial experimental setups,” said principle investigator Ajit Varki. “This is the first time we have directly shown that mimicking the exact situation in humans feeding non-human Neu5Gc and inducing anti-Neu5Gc antibodies—increases spontaneous cancers in mice.” Details about an earlier Neu5Gc study led by the same researchers appear in Issue 280 of this Update.