Inflammation predisposes to tumorigenesis in various organs by potentiating a susceptibility to genetic aberrations. The mechanism underlying the enhanced genetic instability through chronic inflammation, however, is not clear. Here, we demonstrated that TNFα stimulation induced transcriptional downregulation of MSH2, a member of the mismatch repair family, via NF-κB- dependent miR-21 expression in hepatocytes. Liver cancers developed in ALB-MSH2-/- AID+, ALB-MSH2-/-, and ALB-AID+ mice, in which MSH2 is deficient and/or activation-induced cytidine deaminase (AICDA) is expressed in cells with albumin-producing hepatocytes. The mutation signatures in the tumors developed in these models, especially ALB-MSH2-/- AID+ mice, closely resembled those of human hepatocellular carcinoma. Our findings demonstrated that inflammation-mediated dysregulation of MSH2 may be a mechanism of genetic alterations during hepatocarcinogenesis.
ASJC Scopus subject areas
- Cancer Research