Kaiso is required for MTG16-dependent effects on colitis-associated carcinoma

Oncogene. 2019 Jun;38(25):5091-5106. doi: 10.1038/s41388-019-0777-7. Epub 2019 Mar 11.

Abstract

The myeloid translocation gene family member MTG16 is a transcriptional corepressor that relies on the DNA-binding ability of other proteins to determine specificity. One such protein is the ZBTB family member Kaiso, and the MTG16:Kaiso interaction is necessary for repression of Kaiso target genes, such as matrix metalloproteinase-7. Using the azoxymethane and dextran sodium sulfate (AOM/DSS) murine model of colitis-associated carcinoma, we previously determined that MTG16 loss accelerates tumorigenesis and inflammation. However, it was unknown whether this effect was modified by Kaiso-dependent transcriptional repression. To test for a genetic interaction between MTG16 and Kaiso in inflammatory carcinogenesis, we subjected single and double knockout (DKO) mice to the AOM/DSS protocol. Mtg16-/- mice demonstrated increased colitis and tumor burden; in contrast, disease severity in Kaiso-/- mice was equivalent to wild-type controls. Surprisingly, Kaiso deficiency in the context of MTG16 loss reversed injury and pro-tumorigenic responses in the intestinal epithelium following AOM/DSS treatment, and tumor numbers were returned to near to wild-type levels. Transcriptomic analysis of non-tumor colon tissue demonstrated that changes induced by MTG16 loss were widely mitigated by concurrent Kaiso loss, and DKO mice demonstrated downregulation of metabolism and cytokine-associated gene sets with concurrent activation of DNA damage checkpoint pathways as compared with Mtg16-/-. Further, Kaiso knockdown in intestinal enteroids reduced stem- and WNT-associated phenotypes, thus abrogating the induction of these pathways observed in Mtg16-/- samples. Together, these data suggest that Kaiso modifies MTG16-driven inflammation and tumorigenesis and suggests that Kaiso deregulation contributes to MTG16-dependent colitis and CAC phenotypes.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adenocarcinoma / genetics*
  • Adenocarcinoma / pathology
  • Animals
  • Carcinogenesis / genetics*
  • Carcinogenesis / metabolism
  • Carcinogenesis / pathology
  • Colitis / complications*
  • Colitis / genetics*
  • Colitis / pathology
  • Colonic Neoplasms / genetics*
  • Colonic Neoplasms / pathology
  • Female
  • HCT116 Cells
  • HEK293 Cells
  • Humans
  • Inflammation / complications
  • Inflammation / genetics
  • Inflammation / metabolism
  • Inflammation / pathology
  • Intestinal Mucosa / metabolism
  • Intestinal Mucosa / pathology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Repressor Proteins / genetics*
  • Transcription Factors / genetics
  • Transcription Factors / physiology*

Substances

  • CBFA2T3 protein, human
  • Repressor Proteins
  • Transcription Factors
  • ZBTB33 protein, human