HSulf-1 modulates FGF2- and hypoxia-mediated migration and invasion of breast cancer cells

Cancer Res. 2011 Mar 15;71(6):2152-61. doi: 10.1158/0008-5472.CAN-10-3059. Epub 2011 Jan 25.

Abstract

HSulf-1 modulates the sulfation states of heparan sulfate proteoglycans critical for heparin binding growth factor signaling. In the present study, we show that HSulf-1 is transcriptionally deregulated under hypoxia in breast cancer cell lines. Knockdown of HIF-1α rescued HSulf-1 downregulation imposed by hypoxia, both at the RNA and protein levels. Chromatin immunoprecipitation with HIF-1α and HIF-2α antibodies confirmed recruitment of HIF-α proteins to the two functional hypoxia-responsive elements on the native HSulf-1 promoter. HSulf-1 depletion in breast cancer cells resulted in an increased and sustained bFGF2 (basic fibroblast growth factor) signaling and promoted cell migration and invasion under hypoxic conditions. In addition, FGFR2 (fibroblast growth factor receptor 2) depletion in HSulf-1-silenced breast cancer cells attenuated hypoxia-mediated cell invasion. Immunohistochemical analysis of 53 invasive ductal carcinomas and their autologous metastatic lesions revealed an inverse correlation for the expression of HSulf-1 to CAIX in both the primary tumors (P ≥ 0.0198) and metastatic lesions (P ≥ 0.0067), respectively, by χ(2) test. Finally, HSulf-1 expression levels in breast tumors by RNA in situ hybridization showed that high HSulf-1 expression is associated with increased disease-free and overall survival (P ≥ 0.03 and P ≥ 0.0001, respectively). Collectively, these results reveal an important link between loss of HSulf-1 under hypoxic microenvironment and increased growth factor signaling, cell migration, and invasion.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Basic Helix-Loop-Helix Transcription Factors / genetics
  • Basic Helix-Loop-Helix Transcription Factors / metabolism
  • Breast Neoplasms / genetics*
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology
  • Cell Hypoxia
  • Cell Line, Tumor
  • Cell Movement*
  • Female
  • Fibroblast Growth Factor 2 / genetics*
  • Fibroblast Growth Factor 2 / metabolism
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / genetics
  • Hypoxia-Inducible Factor 1, alpha Subunit / metabolism
  • Immunoblotting
  • Immunohistochemistry
  • In Situ Hybridization
  • Middle Aged
  • Neoplasm Invasiveness
  • Protein Binding
  • RNA Interference
  • Response Elements / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sulfotransferases / genetics*
  • Sulfotransferases / metabolism
  • Survival Analysis
  • Tissue Array Analysis

Substances

  • Basic Helix-Loop-Helix Transcription Factors
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Fibroblast Growth Factor 2
  • endothelial PAS domain-containing protein 1
  • SULF1 protein, human
  • Sulfotransferases