STC1 expression is associated with tumor growth and metastasis in breast cancer

Clin Exp Metastasis. 2015 Jan;32(1):15-27. doi: 10.1007/s10585-014-9687-9. Epub 2014 Nov 13.

Abstract

Stanniocalcin-1 (STC1) is a secreted glycoprotein implicated in several pathologies including retinal degeneration, cerebral ischemia, angiogenesis and inflammation. Aberrant STC1 expression has been reported in breast cancer but the significance of this is not clear. High levels of STC1 expression were found in the aggressive 4T1 murine mammary tumor cells and in the MDA-MB-231 human breast cancer line. To investigate its significance, stable clones with STC1 down-regulation using shRNA were generated in both tumor models. The consequences of STC1 down-regulation on cell proliferation, chemotactic invasion, tumor growth and metastasis were assessed. Down-regulation of STC1 in the 4T1 murine mammary tumor cells had a major impact on mammary tumor growth. This observation was replicated in a second tumor model with the MDA-MB-231 human breast cancer line, with a significant reduction in primary tumor formation and a major inhibition of metastasis as well. Interestingly, in both models, proliferation in vitro was not affected. Subsequent microarray gene expression profiling identified 30 genes to be significantly altered by STC1 down-regulation, the majority of which are associated with known hallmarks of carcinogenesis. Furthermore, bioinformatic analysis of breast cancer datasets revealed that high expression of STC1 is associated with poor survival. This is the first study to show definitively that STC1 plays an oncogenic role in breast cancer, and indicates that STC1 could be a potential therapeutic target for treatment of breast cancer patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bone Neoplasms / secondary*
  • Breast Neoplasms / pathology*
  • Cell Line, Tumor
  • Cell Proliferation
  • Down-Regulation
  • Female
  • Gene Expression Profiling
  • Gene Expression Regulation, Neoplastic
  • Glycoproteins / biosynthesis*
  • Glycoproteins / genetics
  • Humans
  • Liver Neoplasms / secondary*
  • Lung Neoplasms / secondary*
  • Lymphatic Metastasis
  • Mice
  • Mice, Inbred BALB C
  • Mice, SCID
  • Neoplasm Invasiveness / genetics
  • RNA Interference
  • RNA, Small Interfering

Substances

  • Glycoproteins
  • RNA, Small Interfering
  • teleocalcin