By now, you’ve probably heard that your body is teeming with bacteria. Some 100 trillion of them live on your skin, in your mouth and in the coils of your intestines. Some protect against infections and help you digest food, while others can make you seriously ill.
Fungi, viruses and protozoa call your body their home, too. Your fungal residents are less numerous than your bacteria by orders of magnitude, but as researchers are learning, these overlooked organisms play an important physiological role — and when their numbers get out of whack, they can modify your immune system and even influence the development of cancer.
A new study, published Wednesday in the journal Nature, found that fungi can make their way deep into the pancreas, which sits behind your stomach and secretes digestive enzymes into your small intestine. In mice and human patients with pancreatic cancer, the fungi proliferate 3,000-fold compared to healthy tissue — and one fungus in particular may make pancreatic tumors grow bigger.
One particular fungus was the most abundant in the pancreas: a genus of Basidiomycota called Malassezia, which is typically found on the skin and scalp of animals and humans, and can cause skin irritation and dandruff. A few studies have also linked the yeast to inflammatory bowel diseases, but the new finding is the first to link it to cancer.
The results show that Malassezia was not only abundant in mice that got pancreatic tumors, it was also present in extremely high numbers in samples from pancreatic cancer patients, said Dr. Berk Aykut, a postdoctoral researcher in Dr. Miller’s lab.
Nearly 57,000 people will be diagnosed with pancreatic cancer in the United States this year, but their prognosis will be poor. Three-fourths die within a year of diagnosis, and only about 1 in 10 live longer than five years.
Read the complete article in the New York Times here.