M. sympodialis is considered to be a normal commensal of the human oral microbiome [79], though a recent in vivo study utilising mouse tumour models demonstrated increased Malassezia abundance in pancreatic tumour mice compared to controls, with further knockout mice suggesting that tumour progression is driven by activation of the mannose-binding lectin—C3 complement cascade [80]. This evidence concerns the gene MBL2 and neoplasm.