The fungus Malassezia promotes pancreatic cancer

George Miller, Berk Aykut and colleagues show that the fungal mycobiome undergoes quantitative and qualitative changes in the pancreatic microenvironment during oncogenesis, as compared to the gut or normal pancreas. They show that one specific fungus, Malassezia, is sufficient to promote pancreatic cancer development. the lectin MBL binds to the fungus and this activates the complement cascade which is responsible for the tumour-promoting ability of Malassezia, led by binding of complement C3 to its receptor on tumour cells.