YAP-IL-6ST autoregulatory loop activated on APC loss controls colonic tumorigenesis

Proc Natl Acad Sci U S A. 2017 Feb 14;114(7):1643-1648. doi: 10.1073/pnas.1620290114. Epub 2017 Jan 27.

Abstract

Loss of tumor suppressor adenomatous polyposis coli (APC) activates β-catenin to initiate colorectal tumorigenesis. However, β-catenin (CTNNB1) activating mutations rarely occur in human colorectal cancer (CRC). We found that APC loss also results in up-regulation of IL-6 signal transducer (IL-6ST/gp130), thereby activating Src family kinases (SFKs), YAP, and STAT3, which are simultaneously up-regulated in the majority of human CRC. Although, initial YAP activation, which stimulates IL6ST gene transcription, may be caused by reduced serine phosphorylation, sustained YAP activation depends on tyrosine phosphorylation by SFKs, whose inhibition, along with STAT3-activating JAK kinases, causes regression of established colorectal tumors. These results explain why APC loss is a more potent initiating event than the mere activation of CTNNB1.

Keywords: IL-6ST/gp130; STAT3; YAP; adenomatous polyposis coli; colorectal cancer.

Publication types

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

MeSH terms

  • Adenomatous Polyposis Coli Protein / genetics
  • Adenomatous Polyposis Coli Protein / metabolism*
  • Adult
  • Aged
  • Animals
  • Carcinogenesis / genetics
  • Carcinogenesis / metabolism
  • Cell Cycle Proteins
  • Cell Line, Tumor
  • Colorectal Neoplasms / genetics
  • Colorectal Neoplasms / metabolism*
  • Colorectal Neoplasms / pathology
  • Cytokine Receptor gp130 / genetics
  • Cytokine Receptor gp130 / metabolism*
  • Female
  • HCT116 Cells
  • HEK293 Cells
  • HT29 Cells
  • Humans
  • Male
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mice, Transgenic
  • Middle Aged
  • Mutation
  • Nuclear Proteins / metabolism*
  • Transcription Factors / metabolism*
  • beta Catenin / genetics
  • beta Catenin / metabolism

Substances

  • Adenomatous Polyposis Coli Protein
  • CTNNB1 protein, human
  • Cell Cycle Proteins
  • IL6ST protein, human
  • Nuclear Proteins
  • Transcription Factors
  • YY1AP1 protein, human
  • beta Catenin
  • Cytokine Receptor gp130