Gut Mucosal Microbiome Signatures of Colorectal Cancer Differ According to BMI Status

Area of Science:

• Microbiome research
• Oncology
• Human physiology

Background:

• Excess body weight is a significant risk factor for colorectal cancer (CRC).
• Mechanisms linking obesity to CRC are not fully understood, but inflammation and gut microbiota alterations are implicated.
• Approximately 11% of European CRC cases are associated with being overweight.

Purpose of the Study:

• To investigate if excess body weight is associated with a distinct gut microbial signature in colorectal cancer (CRC) patients.
• To compare the mucosal-associated microbiota of CRC patients with varying body mass index (BMI) statuses.

Main Methods:

• Analysis of colonic mucosal biopsies from 20 CRC patients and 11 healthy controls.
• Comparison of microbial signatures between CRC lesions, adjacent normal mucosa, and healthy controls.
• Assessment of the influence of BMI >25 kg/m² on colonic microbial composition.

Main Results:

• Confirmed an over-abundance of Fusobacteria in CRC patients.
• Identified an increase in Fusobacteria and Prevotella associated with a BMI >25 kg/m².
• Observed more co-exclusive and transphylum bacterial relationships in CRC patients with a BMI >25 kg/m².

Conclusions:

• Gut microbiota composition in CRC patients is influenced by BMI status.
• Distinct microbial signatures associated with higher BMI in CRC patients warrant further investigation.
• Understanding these BMI-associated microbial differences can inform novel screening and therapeutic strategies for CRC.