ALT Timeline of recent tumor microbiome studies in humans, highlighting microbiome existence across different tumor tissues, including both high- and low-biomass tumors. The year 2020 (dashed line) marked a breakthrough in tumor microbiome research, as microbiomes were derived from host-based sequencing data, significantly bringing impact to this field. Circle and triangle nodes in different colors represent tumor tissues biopsied from various organs: nodes with no fill represent tumor tissues biopsied from metastatic organs, while navy highlighting indicates the detection techniques used in each study. EBV, Epstein–Barr virus; HBV, hepatitis V virus; HCV, hepatitis C virus; HHV, human herpesvirus; HIV, human immunodeficiency virus; HPV, human papillomavirus; HTLV-1, human T lymphotropic virus 1; 16S, 16S rRNA sequencing; FISH, fluorescence in situ hybridization; ITS, internal transcribed spacer; WGS, whole-genome sequencing. b, Tumor microbiome studies conducted in mouse models. c, Overvi

ALT Steps include data acquisition, reference mapping, decontamination and filtering, downstream analysis and prediction validation.