Microbiome
Is the colon lining’s microbiome different in cancer?
Open access · cc by · source: Europe PMC
In 31 CRC patients vs 30 healthy volunteers, tumor mucosa had lower 16S diversity, more Firmicutes and Fusobacteria, and less Proteobacteria; Lactococcus/Fusobacterium rose in tumors while Pseudomonas fell.
Study at a glance
- Design
- Case-control — 16S V3 pyrosequencing of CRC mucosa vs adjacent tissue vs healthy colonoscopy controls, including proximal vs distal tumors
- N
- N=61 · 31 CRC patients (31 tumor, 20 adjacent; 15 proximal, 16 distal) plus 30 healthy volunteers (15 proximal, 15 distal mucosa); 81 sequenced samples
- Population
- Recently diagnosed CRC patients and healthy colonoscopy volunteers (Shanghai Sixth People's Hospital)
- Outcome
- Mucosa-associated 16S community structure, diversity, and taxon abundances
Structured fields used in claim comparison tables when every cited study has a complete layer.
Key findings
Shannon diversity 3.43 vs 4.01 in CRC vs healthy (P<0.001). Firmicutes 63.46% vs 43.36%; Proteobacteria 10.66% vs 60.35%; Fusobacteria 10.58% vs 0.03% (all P<0.001). Tumors vs adjacent: more Firmicutes (P=0.03), less Proteobacteria (P<0.01); Lactococcus 50.85% vs 25.35% (P=0.007).
Methodology
Pyrosequenced 16S rRNA V3 from 31 CRC tumors, 20 adjacent non-cancerous mucosa, and 30 healthy mucosal samples (proximal and distal), clustering OTUs at 97% identity (mean 17,018 reads/sample).
Limitations
Cross-sectional mucosa snapshots cannot prove these taxa cause CRC or that probiotics would treat it; relative abundances from V3 454 data are not absolute counts.
How this study connects
Role on claims
Each row is a claim on a concept or method page where this paper supports, challenges, or qualifies the statement. Roles are hand-checked — not a model guess.
CRC tumor mucosa had lower 16S diversity, more Fusobacteria, and less Proteobacteria than healthy gut.
In 31 CRC patients vs 30 healthy volunteers, Shannon diversity was 3.43 vs 4.01 (P<0.001). Tumor mucosa had more Firmicutes (63.46% vs 43.36%) and Fusobacteria (10.58% vs 0.03%) and less Proteobacteria (10.66% vs 60.35%). Tumors vs adjacent mucosa: Lactococcus 50.85% vs 25.35%.
Evidence for the claim as stated.
Two-sample MR links specific gut taxa to postpartum hemorrhage and other pregnancy outcomes.
MR of 18,340 MiBioGen participants versus FinnGen pregnancy GWAS found taxon-specific IVW signals—e.g. Deltaproteobacteria raising PPH risk (OR 1.26) and Butyricimonas lowering it (OR 0.79); Holdemanella OR 0.41 for abruptio placentae. All F statistics were >10.
Scope note — CRC mucosa 16S case-control ≠ genetic instruments for pregnancy GWAS
Limits the claim's scope: a different population, assay, or outcome.
A Himalayan lifestyle-gradient community shift, mouse OMV rescue of DSS colitis, CRC mucosa 16S, and pregnancy-outcome MR all involve gut microbes, but they do not test the same host, exposure, or outcome as cancer MR or pediatric T1D timing studies.
Evidence for the claim as stated.
Open questions
Tensions this paper is part of
From concept pages' “where studies disagree.” Disagreement means the same question; scope means different assays, populations, or outcomes.
A Himalayan lifestyle-gradient community shift, mouse OMV rescue of DSS colitis, CRC mucosa 16S, and pregnancy-outcome MR all involve gut microbes, but they do not test the same host, exposure, or outcome as cancer MR or pediatric T1D timing studies.
History
When this study was placed
Dated entries from the concept change log — when this paper was added or removed as support, challenge, or qualifier on a claim.
Placed as supporting evidence on Microbiome
In 31 CRC patients vs 30 healthy volunteers, Shannon diversity was 3.43 vs 4.01 (P<0.001). Tumor mucosa had more Firmicutes (63.46% vs 43.36%) and Fusobacteria (10.58% vs 0.03%) and less Proteobacteria (10.66% vs 60.35%). Tumors vs adjacent mucosa: Lactococcus 50.85% vs 25.35%.
Placed as a scope qualifier on Microbiome
MR of 18,340 MiBioGen participants versus FinnGen pregnancy GWAS found taxon-specific IVW signals—e.g. Deltaproteobacteria raising PPH risk (OR 1.26) and Butyricimonas lowering it (OR 0.79); Holdemanella OR 0.41 for abruptio placentae. All F statistics were >10.
Placed as supporting evidence on Microbiome
A Himalayan lifestyle-gradient community shift, mouse OMV rescue of DSS colitis, CRC mucosa 16S, and pregnancy-outcome MR all involve gut microbes, but they do not test the same host, exposure, or outcome as cancer MR or pediatric T1D timing studies.
Related papers in this topic
Same topic cluster — not a recommendation engine.