Pten in Stromal Fibroblasts Suppresses Mammary Epithelial Tumours

Nature. 2009 Oct 22;461(7267):1084-91. doi: 10.1038/nature08486.

Abstract

The tumour stroma is believed to contribute to some of the most malignant characteristics of epithelial tumours. However, signalling between stromal and tumour cells is complex and remains poorly understood. Here we show that the genetic inactivation of Pten in stromal fibroblasts of mouse mammary glands accelerated the initiation, progression and malignant transformation of mammary epithelial tumours. This was associated with the massive remodelling of the extracellular matrix (ECM), innate immune cell infiltration and increased angiogenesis. Loss of Pten in stromal fibroblasts led to increased expression, phosphorylation (T72) and recruitment of Ets2 to target promoters known to be involved in these processes. Remarkably, Ets2 inactivation in Pten stroma-deleted tumours ameliorated disruption of the tumour microenvironment and was sufficient to decrease tumour growth and progression. Global gene expression profiling of mammary stromal cells identified a Pten-specific signature that was highly represented in the tumour stroma of patients with breast cancer. These findings identify the Pten-Ets2 axis as a critical stroma-specific signalling pathway that suppresses mammary epithelial tumours.

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

  • Animals
  • Breast Neoplasms / metabolism*
  • Breast Neoplasms / pathology*
  • Cell Line, Tumor
  • Cell Proliferation
  • Cell Transformation, Neoplastic
  • Extracellular Matrix / metabolism
  • Fibroblasts / metabolism*
  • Gene Deletion
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Immunity, Innate
  • Mammary Neoplasms, Experimental / metabolism
  • Mammary Neoplasms, Experimental / pathology
  • Mice
  • Mice, Transgenic
  • Neoplasms, Glandular and Epithelial / metabolism*
  • Neoplasms, Glandular and Epithelial / pathology*
  • PTEN Phosphohydrolase / deficiency
  • PTEN Phosphohydrolase / genetics
  • PTEN Phosphohydrolase / metabolism*
  • Proto-Oncogene Protein c-ets-2 / deficiency
  • Proto-Oncogene Protein c-ets-2 / metabolism
  • Stromal Cells / metabolism*

Substances

  • Ets2 protein, mouse
  • Proto-Oncogene Protein c-ets-2
  • PTEN Phosphohydrolase
  • PTEN protein, human
  • Pten protein, mouse