ITGB1-dependent upregulation of Caveolin-1 switches TGFβ signalling from tumour-suppressive to oncogenic in prostate cancer

Sci Rep. 2018 Feb 5;8(1):2338. doi: 10.1038/s41598-018-20161-2.

Abstract

Caveolin-1 (CAV1) is over-expressed in prostate cancer (PCa) and is associated with adverse prognosis, but the molecular mechanisms linking CAV1 expression to disease progression are poorly understood. Extensive gene expression correlation analysis, quantitative multiplex imaging of clinical samples, and analysis of the CAV1-dependent transcriptome, supported that CAV1 re-programmes TGFβ signalling from tumour suppressive to oncogenic (i.e. induction of SLUG, PAI-1 and suppression of CDH1, DSP, CDKN1A). Supporting such a role, CAV1 knockdown led to growth arrest and inhibition of cell invasion in prostate cancer cell lines. Rationalized RNAi screening and high-content microscopy in search for CAV1 upstream regulators revealed integrin beta1 (ITGB1) and integrin associated proteins as CAV1 regulators. Our work suggests TGFβ signalling and beta1 integrins as potential therapeutic targets in PCa over-expressing CAV1, and contributes to better understand the paradoxical dual role of TGFβ in tumour biology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Caveolin 1 / metabolism*
  • Cell Line, Tumor
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Intracellular Signaling Peptides and Proteins / metabolism*
  • Male
  • Membrane Proteins / metabolism*
  • Oncogenes
  • Phenotype
  • Prostatic Neoplasms / genetics
  • Prostatic Neoplasms / metabolism*
  • Signal Transduction
  • Transforming Growth Factor beta1 / metabolism*
  • Up-Regulation

Substances

  • Adaptor Proteins, Signal Transducing
  • CAV1 protein, human
  • Caveolin 1
  • ITGB1BP1 protein, human
  • Intracellular Signaling Peptides and Proteins
  • Membrane Proteins
  • TGFB1 protein, human
  • Transforming Growth Factor beta1