Acetyltransferase from blunts colorectal tumourigenesis by reprogramming tumour microenvironment.

OBJECTIVE

The protein post-translational modification (PTM) in host cells can be rewritten by bacterial enzymes and represents an unprecedented mechanism in the communication between intestinal flora and the host. Although has been widely investigated as a probiotic and blunts colitis-associated tumourigenesis in mice, there is little understanding regarding whether is involved in the PTM of colorectal cancer (CRC). This study investigates whether and how engages in the PTM of host CRC.

DESIGN

The secreting extracellular vesicles from and purified Amuc_2172 were used for different tumourigenesis mice models. Amuc_2172-induced immune activity of CD8 cytotoxic T lymphocytes (CTLs) were evaluated in vitro and in vivo. The acetyltransferase activity and downstream target genes of Amuc_2172 were investigated.

RESULTS

Amuc_2172, a general control non-derepressible 5-related acetyltransferase of , was accessible to colorectal cells by macropinocytosis and functioned as an acetyltransferase of Lys14 on histone H3 (H3K14ac). Elevated H3K14ac on loci promoted the transcription and secretion of heat-shock protein 70 (HSP70) in cancer cells. High level of HSP70 promoted the immune activity of CTLs in vitro and in vivo. Moreover, bioengineered nanoparticles provided a safe and reliable drug delivery strategy of Amuc_2172 for CRC treatment in an allograft mice model.

CONCLUSION

Amuc_2172 reprogrammed tumour microenvironment by inducing HSP70 secretion and promoting CTL-related immune response in the process of tumourigenesis.