The study used an animal model based on mice that are genetically modified to automatically develop polyps in the large intestine and will eventually develop colon cancer.
The mice were provided either tap water with Andosan™ or pure tap water for 15 or 22 weeks. The intestines were then examined by microscopy without the examiner being aware of which samples were taken from treated mice or not (blindly). Andosan™ treated mice had a significantly lower number of tumors as well as a 60% reduction in intestinal tumor load compared to the control group. Furthermore, Andosan™ had a significant cytotoxic effect correlating with induced programmed cell death on human cancer colon cells in vitro.
The results from this mouse model for colorectal cancer shows significant protection of orally administered Andosan™ against development of intestinal cancer. Moreover, the researchers discovered less of the tumor promoting enzyme legumain in intestines of Andosan™ treated mice and they also noticed increased systemic cytokine response in the part of the innate immune system that is engaged in fighting tumors. The mechanism is probably both immunomodulatory and growth inhibition of tumor cells by induction of programmed cell death.
Colorectal cancer is the 4th most frequent type of cancer in Western societies, but the 2nd deadliest after lung cancer. There is increasing evidence for a link between inflammation and colorectal cancer. Approximately 14% of colon cancer has a hereditary background, such as for the inflammatory bowel disease or ulcerative colitis. Previous clinical trials in human patients have found reduced levels of pro-inflammatory serum cytokines after intake of Andosan™ in patients with the inflammatory bowel disease, Crohn’s disease and ulcerative colitis – the latter of which predisposes for colon cancer. Improved clinical effects were observed after 3 weeks of daily intake of 60 ml Andosan™.
Legumain is a tumor-associated enzyme that is expressed in kidney, placenta, and spleen. High levels of the protease legumain have been detected in solid tumors and associated with increased tumor invasion and metastasis. Legumain has been detected on tumor cell surface and in tumor microenvironment, where it has been shown to destroy extracellular matrix by degrading its major component, fibronectin. Moreover, legumain is found on tumor associated macrophages, which are important for tumor development and metastasis. Legumain is highly expressed in colorectal cancer cell lines and associated with poor consequences in colon cancer.
The outcome of this study indicates a role for Andosan™ in the treatment of colorectal cancer and further strengthens the case for using Andosan™ as add-on treatment for patients suffering from ulcerative colitis.
The study was conducted by researchers from Oslo University Hospital, University of Oslo, Oslo, Norwegian Institute of Public Health and University of Life Sciences, Oslo, Norway. The report from the study was edited by Regine Schneider-Stock at the Institute of Pathology, Germany and published in the high-impact journal Plos One in December 2016.
- Hetland G, Eide DM, Tangen JM, Haugen MH, Mirlashari MR, Paulsen JE (2016) The Agaricus blazei-Based Mushroom Extract, Andosan™, Protects against Intestinal Tumorigenesis in the A/J Min/+ Mouse. PLoS ONE 11(12): e0167754. doi:10.1371/journal.pone.0167754