U of I researcher Elvira de Mejia has found that the soy peptide lunasin binds to a specific receptor in highly metastatic colon cancer cells, preventing them from attaching to the liver.
"When lunasin was used in combination with the chemotherapy drug oxaliplatin, we saw a sixfold reduction in the number of new tumor sites," said de Mejia, a U of I associate professor of food chemistry and food toxicology.
The study appears in the most recent issue of Cancer Letters and can be accessed online at http://www.sciencedirect.com/science/article/pii/S0304383511005325 . In a separate study, the scientists showed that lunasin induces cell death in highly metastatic human colon cancer cells.
According to de Mejia, almost all colon cancer deaths are caused when cancer metastasizes—or spreads—to the liver. Until now chemotherapy has targeted the primary tumor because the process of metastasis is not well understood, she said.
"In this study, we have learned that lunasin can penetrate the cancer cell, cause cell death, and interact with at least one type of receptor in a cell that is ready to metastasize," said Vermont P. Dia, a U of I postdoctoral fellow in the de Mejia laboratory and lead author of the study.
When that receptor is blocked, new blood vessels can't form and differentiate, and that prevents cancer from spreading. Binding such receptors has emerged as a promising target for developing cancer therapies, he said.
In the study, which mimicked the spread of colon cancer in humans, mice were separated into four groups: a control group; a group that was injected daily with lunasin; a group injected with the chemo drug oxaliplatin; and a group that received both lunasin and oxaliplatin. After 28 days, the mice were examined to learn the extent of cancer's involvement in the liver.
"The group that received lunasin alone had 50 percent fewer metastatic sites. But an even more exciting result was seen in the group that received both lunasin and the chemotherapy drug—only 5 new cancer sites when compared with 28 in the control group," de Mejia noted.
"This huge reduction in metastasis was achieved with the amount of lunasin in only 25 daily grams of soy protein, the amount recommended in the FDA health claim," Dia said.
The researchers said they recently analyzed commercial soy milks available in their area, and all contained lunasin. However, the amount of lunasin depended on the type of soy product that was used to prepare the soy milk.
"Two glasses of soy milk a day generally provide half the amount of lunasin used in our study," said de Mejia. "It certainly seems feasible to create a lunasin-enriched product that people could consume in a preventive way."
The scientists said their next step will be a colon cancer study in which they make lunasin part of the animals' diet—rather than injecting the peptide—to see if digestion and absorption alter its effectiveness. Soon they hope to be able to move on to human trials.
Dia received the American Oil Chemists Society's 2011 Hans Kaunitz Award for his work with lunasin.
Vermont P. Dia and Elvira de Mejia of the U of I are co-authors of both the study published in Cancer Letters and the in vitro study of lunasin's effect on human cancer cells published in Molecular Nutrition & Food Research, vol. 55, p. 623-634, 2011, available online at www://onlinelibrary.wiley.com/doi/10.1002/mnfr.201000419/pdf. Funding was provided by the USDA, the U of I College of ACES Office of Research, and the Illinois Soybean Association.
Phyllis Picklesimer | EurekAlert!
Usher syndrome: Gene therapy restores hearing and balance
25.09.2017 | Institut Pasteur
MRI contrast agent locates and distinguishes aggressive from slow-growing breast cancer
25.09.2017 | Case Western Reserve University
At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.
Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
25.09.2017 | Power and Electrical Engineering
25.09.2017 | Health and Medicine
25.09.2017 | Physics and Astronomy