Presentation description

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths worldwide, with incidence rising alarmingly among young adults. Alarmingly, the incidence of CRC in younger patients continues to rise, underscoring the urgent need for research into environmental risk factors-particularly diet, lifestyle, and the role of the intestinal microbiota. Novel findings from our laboratory demonstrate a protective role for a previously underappreciated member of the gut microbiota. Our study explores the therapeutic potential of outer membrane vesicles (OMVs) derived from Bacteriorides uniformis, a beneficial gut commensal bacteria known to reduce tumor burden, particularly when combined with immune checkpoint inhibitors such as anti-CLTA4 treatment. (Weis 2025).

OMVs are nanoparticle vesicles containing important packaged components such as polysaccharides, RNAs, and lipids that can modulate immune responses within intestinal epithelial cells (IECs). In our study, CRC was induced with MC38 cells in mice. Mice were treated via daily oral gavage with phosphate-buffered saline (PBS), wild-type B. uniformis OMVs (WT), and parent microbe OMVs. After treatment, tissues from inguinal tumors, inguinal lymph nodes, and colons were harvested and analyzed to evaluate tumor growth and immune activity. Our findings showed that OMVs from B. uniformis effectively decreased tumor burden in CRC.

Our research aims to solidify whether OMVs from B. uniformis reduce inflammation and tumor burden in addition with immune checkpoint inhibitors, supporting their strong potential as a novel, non-invasive OMV based therapy. Our findings contribute to a growing interest in microbe-host interactions and calls us to investigate further in the microbiome and cancer crosstalk.