evidence: Cancer-associated fungi found in different body sites and gene expression signatures. Fungi found to promote tumorigenesis in different body sites (lung, breast, skin, brain, bone, ovary, colon, head-and-neck, stomach) are listed. Fungi that were highly enriched in cancers and may serve as potential prognostic markers are highlighted in red. The presence of Candida in head-and-neck and colon tumors appears to be associated with pro-tumorigenic and cellular adhesion-related gene pathways, whereas in stomach tumors it seems to be involved in inflammatory responses that ultimately lead to poor prognosis. Multiple fungal-bacterial-immune ecologies were detected across tumors. These mycotypes may be promising to predict the survival of patients with cancer [...] When it came to the compositions of fungi in cancers, they found that gastrointestinal (GI) cancers differed in their richness of Candida and Saccharomyces and can thus be classified into Candida-dominant (Ca-type) and Saccharomyces-dominant (Sa-type) tumors. Fungal infection is often associated with T helper 2 (TH2)-type allergic reactions. Interestingly, these two types of GI cancers showed different gene expression patterns and immune responses. For instance, Ca-type tumors were linked with the overexpression of pro-inflammatory cytokines such as interleukin (IL)-1 and IL-6, suggesting a Type 17 signature. Unlike Candida, which was observed mostly in stomach cancers, Blastomyces were dominant in lung tumor samples, and Malassezia was prevalent in breast cancers. In addition, the presence of Candida was regarded as a predictive biomarker of late-stage disease in GI cancers, and was associated with poor survival (Fig. 1).