Gut microbiota signatures in colorectal cancer: Evidence synthesis from umbrella review and probiotic intervention studies

Table 2 Characteristics of the included studies (n = 11)

Ref.	First author	Journal and year	k meta	CRC cases (n)	Controls (n)	Country	Objective of study	Outcome
Liu et al[11]	Ning-Ning Liu	Nature Microbiology, 2022	5	491	494	Austria, France, Germany, China, Japan, Italy, and United States	To analyze multi-kingdom gut microbiome alterations in CRC and identify reproducible diagnostic biomarkers	CRC showed multi-kingdom dysbiosis, with 16 validated biomarkers and altered D-amino acid and butanoate metabolism
Li et al[12]	Tian-Hui Li	Gastroenterology, 2025	11	738	896	China, Austria, United States, Italy, Japan, Germany, and France	To characterize CRC-associated gut archaea and assess their interactions with bacterial communities	CRC showed reduced archaeal diversity, altered methanogenesis-related taxa, and improved diagnostic performance in combined archaea-bacteria models
Jiang et al[21]	Pu-Zi Jiang	mSystems, 2021	7	354	357	Japan, China, United States, Germany, France, Australia, and Italy	To identify shared and disease-specific microbial signatures across CD (Crohn’s disease), UC (ulcerative colitis), and CRC	Species- and pathway-level biomarkers were identified, with UC and CRC showing greater microbial similarity and strong diagnostic potential
Jin et al[18]	Dong-Min Jin	mSystems, 2024	3 (CRC only)	141	141	Germany, Austria, and France	To develop an interpretable meta-analysis workflow for comparing microbiome features across diseases	Disease pairs showed varying microbiome similarities, reflecting both pathogen enrichment and depletion of beneficial microbes
Lin et al[19]	Yu-Feng Lin	Gastroenterology, 2022	8	454	525	Canada, United States, Germany, France, Italy, China, Japan, and Australia	To investigate CRC-associated gut mycobiota and evaluate fungal biomarkers for diagnosis	CRC showed fungal dysbiosis, and fungal-bacterial biomarkers improved diagnostic performance over bacterial markers alone
Wirbel et al[20]	Jakob Wirbel	Nature Medicine, 2019	8	386	392	France, Austria, China, United States, Germany, Italy, and Japan	To identify robust taxonomic and functional microbial signatures of CRC across heterogeneous cohorts	CRC was associated with 29 core enriched species, increased protein and mucin degradation, and elevated secondary bile acid production
Kharofa et al[13]	Jordan Kharofa	Cancer Medicine, 2023	11	692	609	Austria, Canada, China, Germany, France, India, Italy, Japan, and United States	To compare microbial features between early-onset and late-onset CRC, including virulence factors	Early-onset CRC showed distinct microbial and virulence profiles, including associations with colibactin, Fusobacterium adhesin A, and Fusobacterium nucleatum
Thomas et al[10]	Andrew Maltez Thomas	Nature Medicine, 2019	7	313	308	Austria, France, Germany, Italy, Denmark, United States, China, and Japan	To identify reproducible CRC-associated biomarkers and explore related functional mechanisms	CRC showed increased microbial richness, reproducible markers such as Fusobacterium nucleatum, and altered amino acid, gluconeogenesis, and choline metabolism
Piccinno et al[15]	Gianmarco Piccinno	Nature Medicine, 2025	18	1471	1568	Austria, China, Czech Republic, France, Germany, India, Italy, Japan, Spain, Turkey, and United States	To examine gut microbiome changes across adenoma-carcinoma progression, CRC stage, and tumor location	CRC microbiomes were enriched with oral taxa, and cross-cohort classifiers showed strong predictive performance with reproducible species- and strain-level markers
Zhu et al[17]	Xin-Yue Zhu	Communications Biology, 2024	8	485	496	Austria, China, France, Germany, Italy, and United States	To compare multi-kingdom microbial signatures between excess body weight CRC (EBW-CRC) and lean CRC	EBW-CRC and lean-CRC showed distinct microbial and functional patterns, with the EBW-CRC classifier achieving strong validation performance
Chen et al[16]	Fang Chen	Journal of Advanced Research, 2023	9	554	546	France, China, Austria, United States, Canada, Italy, Germany, and Japan	To identify reproducible gut virome signatures in CRC and adenoma and assess their diagnostic potential	CRC and adenoma showed altered viral profiles, and viral biomarkers demonstrated diagnostic potential across cohorts

CRC: Colorectal cancer; CD: Crohn’s disease; UC: Ulcerative colitis; EBW: Excess body weight.