Alterations in gut microbiota and metabolic profiling are associated with papillary thyroid cancer and BRAFV600E mutation
摘要
Emerging evidence indicates that gut microbial dysbiosis contributes to cancer development through metabolic regulation. The gut microbial and metabolic characteristics of papillary thyroid cancer (PTC) remain incompletely characterized, and the role of microbial dysbiosis in PTC tumorigenesis is not well understood.
MethodsThis study recruited 70 PTC patients and 70 healthy controls (HCs) and performed 16S rRNA sequencing and LC-MS/MS metabolomic analysis of fecal samples.
ResultsThe PTC group demonstrated significantly greater microbial diversity and richness compared to the HC group. Substantial differences in microbiota composition were also observed between the two groups. Analysis revealed 19 differentially expressed bacterial taxa in PTC patients relative to HCs, including enriched pathogens (Collinsella, Carnobacterium, and Moryella) and depleted protective bacteria (Lacticaseibacillus, Faecalibaculum, Coprobacter, Anaerotruncus, Leuconostoc, and Acetanaerobacterium). A random forest model with 10-fold cross-validation based on all bacteria detected was used and the prediction model performed best with a mean AUC of 0.769 when 21 features including differentially abundant genera Methyloprofundus, Collinsella, TM7a and Acetanaerobacterium were selected. Microbial co-occurrence network analysis demonstrated stronger correlations between bacterial taxa in PTC compared to HC. Metabolomic profiling identified 20 significantly differentially expressed metabolites in PTC, including elevated levels of ornithine and lysine. Further investigation revealed associations between tumor-associated microbes and metabolites involved in ornithine and lysine metabolic pathways, suggesting a potential mechanism through which gut microbiota may correlate with tumorigenesis. Finally, we conducted comparative analysis of microbial and metabolic profiles between BRAF mutation (BRAFmut) and BRAF wild-type (BRAFwt) patients. Integrative analysis indicated that BRAFmut-enriched Halomonas was negatively correlated with leucine and lysine, providing a plausible hypothesis for microbial-mediated mutagenic effects.
ConclusionThis study elucidates the distinctive distribution and correlation patterns of gut metabolites and microbiota in PTC, offering valuable insights into the pathogenesis and progression of thyroid cancer.