2-DE analysis of a new human cell line EM-G3 derived from breast cancer progenitor cells and comparison with normal mammary epithelial cells

Proteomics. 2007 May;7(9):1549-59. doi: 10.1002/pmic.200600907.


We performed a 2-DE analysis of proteins of the newly established spontaneously immortalized clonal cell line EM-G3 derived from a primary lesion of infiltrating ductal breast carcinoma. EM-G3 cells may represent progenitors of the mammary epithelial cells spontaneously immortalized in early phase of cancerogenesis. We compared the protein profile of EM-G3 line with proteins from populations of normal mammary epithelial cells (NME), and determined the phenotype of both types of cells. NME cells are a mixture of both main cell types in breast epithelia, myoepithelial and luminal cells. The EM-G3 breast cancer cell line has a unique basal-like phenotype. We identified proteins that are differently expressed in these cells. Cytokeratin 16, cytokeratin 19, squamous cell carcinoma antigen 1, caphepsin B and caspase 14 were predominantly expressed by NME cells. Cytokeratin 13, isoelectric variant of annexin 5, isoelectric variant of chloride intracellular channel protein 1, glyoxalase 1 and glutamine synthetase were predominantly expressed by EM-G3 cells. The proteins up-regulated in EM-G3 cells may represent potential protein markers of mammary epithelial cells progenitors and may be important in early phase of carcinogenesis.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Breast Neoplasms / chemistry*
  • Carcinoma, Ductal, Breast / chemistry*
  • Cell Line, Tumor*
  • Electrophoresis, Gel, Two-Dimensional
  • Humans
  • Mammary Glands, Human / chemistry
  • Mammary Glands, Human / cytology*
  • Neoplasm Proteins / chemistry*
  • Phenotype
  • Proteome / chemistry*
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  • Stem Cells / chemistry*


  • Neoplasm Proteins
  • Proteome