Deadly mushroom defeats human pancreatic cancer in mice

There is a certain irony to harnessing something typically so poisonous to animals and people for the greater good of battling cancer. But scientists working together in Germany from three separate institutions have done just that. They've harnessed the deadly death cap mushroom--which looks like the white button mushrooms most people eat in salads and in fine cooking--to stop pancreatic cancer in mice without harming healthy tissue.

Their solution was to load the poison into an antibody drawn to a specific protein known as EpCAM, which helped make the substance more targeted. The breakthrough concerning the mushroom, known formally as Amanita phalloides, is published in detail in the Journal of the National Cancer Institute. Scientists from the German Cancer Research Center, the National Center for Tumor Diseases in Heidelberg and the Max Planck Institute for Medical Research collaborated on the effort.

Yes, I called it a breakthrough. I know the word is on the verge of being overused. But the team's work converting the mushroom's deadly α-amanitin poison toward successfully fighting pancreatic cancer in mice is a preclinical milestone of sorts. That's because the toxin typically kills healthy or cancerous cells, and the solution of loading the antibody with the toxin is a novel and simple way to potentially beat back pancreatic tumors but leave the mice unharmed from the poison. (The antibody is drawn to a specific protein known as EpCAM, which are in much of the body but in abundance in pancreatic and other cancers.)

Clearly, there could be both a drug and a drug delivery mechanism here to treat some forms of pancreatic cancer, which can be notoriously hard to treat. This is early research, however, and breakthroughs in animals can't always be replicated in people. And the scientists acknowledge that liver cells are very sensitive to the mushroom toxin, and there is a risk that the treatment would also target healthy cells with the EpCAM molecule. But at least in mice, the results so far have been encouraging, so it is a promising first step.

In the study, mice loaded with transplanted human pancreatic cancer experienced a blocking of subsequent tumor growth from just one injection of the poison-enhanced antibody, the researchers explain. They saw even greater success injecting two larger doses of the antibody, which erased the tumors in 90 percent of the rodents without generating any obvious toxic effects to vital organs typically caused by the mushrooms. Previously, they saw similar results in the lab, using the antibody in a dish to successfully stop pancreatic, colorectal, breast and other cancer cell lines.

(Image: German researchers used a toxin from the deadly death cap mushroom, which resembles edible white button mushrooms--pictured--to stop pancreatic cancer in mice)

- here's the release
- consider the journal abstract