The emergence of 16S rRNA and metagenomic sequencing has gradually
revealed the close relationship between dysbiosis and colorectal cancer
(CRC). Recent studies have confirmed that intestinal dysbiosis plays
various roles in the occurrence, development, and therapeutic response
of CRC. Perturbation of host immunity is one of the key mechanisms.
Intestinal flora, or specific bacterium and its metabolites can modulate
the progression of CRC through Toll-like receptors signaling, or via the
recruitment, polarization and activation of innate and adaptive immune
cells to reshape the pro-/anti-tumor microenvironment. On this basis,
administration of gut bacteria to enhance immune homeostasis represents
new cues for the treatment of CRC. In this review, we will cover the
recent studies on the role of gut bacteria in the progression and
treatment of CRC through immune response orchestration, which
potentially offers insights for subsequent transformative research.