Gut mucosal microbiota profiles linked to development of positional-specific human colorectal cancer.

Colorectal cancer (CRC) continuously ranks as the third most common cause of cancer-related deaths worldwide. Based on anatomical classifications and clinical diagnoses, CRC is classified into right-sided, left-sided, and rectal CRC. Importantly, the three types of positional-specific CRC affect the prognosis outcomes, thus indicating that positional-specific treatments for CRC are required. Emerging evidence suggests that besides host genetic and epigenetic alterations, gut mucosal microbiota is linked to gut inflammation, CRC occurrence, and prognoses. However, gut mucosal microbiota associated with positional-specific CRC are poorly investigated. Here, we report the gut mucosal microbiota profiles associated with these three types of CRC. Our analysis showed that the unique composition and biodiversity of bacterial taxa are linked to positional-specific CRC. We found that a combination of bacterial taxa can serve as potential biomarkers to distinguish the three types of CRC. Further investigations of the physiological roles of bacteria associated with positional-specific CRC may help understand the mechanism of CRC progression in different anatomical locations under the impact of gut mucosal microbiota.