Luminal breast cancer metastasis is dependent on estrogen signaling

Clin Exp Metastasis. 2012 Jun;29(5):493-509. doi: 10.1007/s10585-012-9466-4. Epub 2012 Mar 17.

Abstract

Luminal breast cancer is the most frequently encountered type of human breast cancer and accounts for half of all breast cancer deaths due to metastatic disease. We have developed new in vivo models of disseminated human luminal breast cancer that closely mimic the human disease. From initial lesions in the tibia, locoregional metastases develop predictably along the iliac and retroperitoneal lymph node chains. Tumors cells retain their epithelioid phenotype throughout the process of dissemination. In addition, systemically injected metastatic MCF-7 cells consistently give rise to metastases in the skeleton, floor of mouth, adrenal glands, as well as in the lungs, liver, brain and mammary fat pad. We show that growth of luminal breast cancer metastases is highly dependent on estrogen in a dose-dependent manner and that estrogen withdrawal induces rapid growth arrest of metastatic disease. On the other hand, even though micrometastases at secondary sites remain viable in the absence of estrogen, they are dormant and do not progress to macrometastases. Thus, homing to and seeding of secondary sites do not require estrogen. Moreover, in sharp contrast to basal-like breast cancer metastasis in which transforming growth factor-β signaling plays a key role, luminal breast cancer metastasis is independent of this cytokine. These findings have important implications for the development of targeted anti-metastatic therapy for luminal breast cancer.

Publication types

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

MeSH terms

  • Animals
  • Biomarkers, Tumor / genetics
  • Biomarkers, Tumor / metabolism
  • Blotting, Western
  • Bone Neoplasms / drug therapy*
  • Bone Neoplasms / metabolism
  • Bone Neoplasms / secondary*
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology*
  • Cell Communication
  • Estrogens / pharmacology*
  • Female
  • Gene Expression Profiling
  • Humans
  • Immunoenzyme Techniques
  • Mice
  • Mice, Nude
  • Neoplasm Micrometastasis
  • Oligonucleotide Array Sequence Analysis
  • RNA, Messenger / genetics
  • Real-Time Polymerase Chain Reaction
  • Signal Transduction / drug effects*
  • Transforming Growth Factor beta / pharmacology
  • Tumor Cells, Cultured
  • Wound Healing

Substances

  • Biomarkers, Tumor
  • Estrogens
  • RNA, Messenger
  • Transforming Growth Factor beta