Researchers from the University of Illinois found that consumption of soy peptide can dramatically reduce colon cancer metastasis.
Researchers from the University of Illinois conducted a study to see if soy peptide lunasin can, in any way, reduce colon cancer metastasis. They conducted a two part study on mice that were injected with human colon cancer cells. For the first part, the mice were injected with lunasin along with the chemotherapy drug oxaliplatin. Researchers observed a six-fold reduction in metastatic tumors to the liver.
"We learned in that study 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 Dia, a postdoctoral associate in the de Mejia laboratory, in a press statement.
Since soy is essentially food, scientists wanted to see what would happen if lunasin was consumed as food rather than injected into the body. They also wanted to find out what dose of the lunasin would provide desired results.
For the second part of the study, researchers fed the mice 8 mg/kg soy peptide lunasin daily and observed a 55 percent reduction in the growth of new tumors. They increased the dose five times and finally concluded that a 94 percent reduction in new tumor growth can be achieved by consuming 20 mg/kg of lunasin daily.
"In this new study, we find that giving lunasin orally at 20 mg/kg of body weight reduced the number of metastatic tumors by 94 percent-we went from 18 tumors to only one. And that was done using lunasin alone; no other type of therapy was used," said Elvira de Mejia, a U of I professor of food chemistry and food toxicology.
Authors of the study admit that consumption of large amount of lunasin in soy foods daily can be a daunting task but not impossible. Food companies could begin manufacturing lunasin-enriched soy milk or yogurt.
The results were observed after feeding mice with lunasin for only 28 days. Researchers are now preparing to conduct a study to see the effects of lifelong exposure to lunasin in transgenic mice programmed to develop colon cancer in contrast to a group that did not receive any lunasin.
The findings of the study are published in an online journal of Cancer Therapy.
