Gut microbiome-derived bacterial extracellular vesicles in patients with solid tumours

Area of Science:

• Microbiome research
• Cancer biology
• Nanoparticle analysis

Background:

• Bacterial extracellular vesicles (bEVs) are nanoparticles derived from the gut microbiome.
• bEVs contain proteins, mRNAs, metabolites, and lipids, offering insights into host-gut microbiome interactions.
• Current methods for analyzing gut microbiome composition alone may not fully capture host-gut microbiome communication, especially in solid tumor patients.

Purpose of the Study:

• To compare the proteome and microbiota composition of bEVs from solid tumor patients and healthy controls.
• To investigate the functional role of bEVs in host-gut microbiome interactions within the context of solid tumors.
• To assess the potential of bEVs as diagnostic biomarkers for solid tumors.

Main Methods:

• Isolation of bEVs from fecal samples of solid tumor patients and healthy controls.
• Proteomic analysis of bEVs using spectrometry.
• 16S rRNA gene sequencing for microbiota composition analysis of both bEVs and fecal samples.
• Machine learning for sample classification based on bEV and fecal microbiome data.

Main Results:

• Solid tumor patients exhibited reduced microbiota richness and diversity in both bEVs and feces compared to controls.
• bEV proteomes from patients were more diverse and enriched with proteins involved in amino acid/carbohydrate metabolism and nucleotide binding.
• Machine learning classification achieved 100% accuracy using fecal bEVs, outperforming fecal samples (93%).

Conclusions:

• bEVs represent unique functional entities distinct from the overall gut microbiome.
• bEVs show promise as a more accurate diagnostic tool for solid tumors compared to fecal microbiome analysis alone.
• Further research into bEVs alongside conventional microbiome analysis is crucial for cancer diagnostics and therapeutics.