A chronic signaling TGFb zebrafish reporter identifies immune response in melanoma

Elife. 2024 Jun 14:13:e83527. doi: 10.7554/eLife.83527.

Abstract

Developmental signaling pathways associated with growth factors such as TGFb are commonly dysregulated in melanoma. Here we identified a human TGFb enhancer specifically activated in melanoma cells treated with TGFB1 ligand. We generated stable transgenic zebrafish with this TGFb Induced Enhancer driving green fluorescent protein (TIE:EGFP). TIE:EGFP was not expressed in normal melanocytes or early melanomas but was expressed in spatially distinct regions of advanced melanomas. Single-cell RNA-sequencing revealed that TIE:EGFP+ melanoma cells down-regulated interferon response while up-regulating a novel set of chronic TGFb target genes. ChIP-sequencing demonstrated that AP-1 factor binding is required for activation of chronic TGFb response. Overexpression of SATB2, a chromatin remodeler associated with tumor spreading, showed activation of TGFb signaling in early melanomas. Confocal imaging and flow cytometric analysis showed that macrophages localize to TIE:EGFP+ regions and preferentially phagocytose TIE:EGFP+ melanoma cells compared to TIE:EGFP- melanoma cells. This work identifies a TGFb induced immune response and demonstrates the need for the development of chronic TGFb biomarkers to predict patient response to TGFb inhibitors.

Keywords: TGFb; cancer biology; human; macrophages; melanoma; zebrafish.

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Cell Line, Tumor
  • Gene Expression Regulation, Neoplastic
  • Genes, Reporter*
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Humans
  • Melanoma* / diagnosis
  • Melanoma* / genetics
  • Melanoma* / immunology
  • Signal Transduction*
  • Transforming Growth Factor beta1 / metabolism
  • Zebrafish

Substances

  • Green Fluorescent Proteins
  • Transforming Growth Factor beta1

Associated data

  • GEO/GSE213360