Simultaneous expression of nitric oxide synthase and estrogen receptor in human breast cancer cell lines

Breast Cancer Res Treat. 1996;40(2):205-7. doi: 10.1007/BF01806216.


For various human tumor cell lines (neuroblastoma, cervix carcinoma) the presence of constitutive nitric oxide synthase (cNOS) has been documented. Here, for the first time, we report about cNOS expression in 10 of 16 human breast cancer cell lines. cNOS expression correlates strongly with expression of estrogen receptor (ER). Competitive reverse transcription-polymerase chain reaction (cRT-PCR) was used to detect cNOS and ER mRNA expression. Our findings suggest that estradiol could stimulate constitutive NO release in breast tissue, where it acts as a free radical.

MeSH terms

  • Breast Neoplasms / enzymology*
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / ultrastructure*
  • Humans
  • Nitric Oxide / metabolism
  • Nitric Oxide Synthase / analysis*
  • Nitric Oxide Synthase / metabolism
  • Polymerase Chain Reaction
  • Receptors, Estrogen / analysis*
  • Transcription, Genetic
  • Tumor Cells, Cultured


  • Receptors, Estrogen
  • Nitric Oxide
  • Nitric Oxide Synthase