The multispecies microbial cluster of Fusobacterium, Parvimonas, Bacteroides and Faecalibacterium as a precision...

Area of Science:

• Microbiology
• Oncology
• Gastroenterology

Background:

• Colorectal cancer (CRC) incidence is rising globally, necessitating improved early detection methods.
• Noninvasive biomarkers are crucial for reducing CRC mortality.
• Imbalances in oral and gut microbiomes are linked to CRC, alongside impaired gut vascular barrier function.

Purpose of the Study:

• To investigate the role of oral pathobionts in colorectal cancer.
• To identify potential microbial biomarkers for early CRC diagnosis.
• To analyze microbiome composition in oral and gut samples of CRC patients and healthy individuals.

Main Methods:

• 16S rRNA metabarcoding was used to analyze microbiomes.
• Samples included saliva, crevicular fluid, feces, and intestinal tissues from 93 CRC patients and 30 controls.
• Microbial composition and co-occurrence patterns were analyzed.

Main Results:

• Fusobacterium, Parvimonas, and Bacteroides fragilis were over-represented in CRC patient stool samples.
• Tumor tissues were enriched with periodontal anaerobes like Fusobacterium and Parvimonas.
• Oral pathobionts were found to co-occur in tumor tissues and correlate with gut microbes.

Conclusions:

• Oral pathobionts can migrate to the colon and form synergistic consortia with gut bacteria.
• A combination of Fusobacterium, Parvimonas, Bacteroides, and Faecalibacterium shows potential for a reliable, noninvasive fecal test for early CRC diagnosis.
• This multi-genus approach offers improved diagnostic accuracy compared to single-species biomarkers.