title: Endothelin A receptor blockade does not alter PSA secretion in prostate cancer cell lines.
abstract: BACKGROUND
  Some men treated with atrasentan (ABT-627), an endothelin A (ETA) receptor inhibitor, had declines in their serum PSA levels. It is our hypothesis that this decrease is due to anti-tumoral activity and not a reduction in PSA secretion at the cellular level.
  
  
  METHODS
  Two PSA secreting prostate cancer cell lines (LAPC4 and LNCaP) were treated with atrasentan and an ETB receptor antagonist (A192621) in varying concentrations (10(-6)-10(-10) M) and PSA levels were measured in the culture media.
  
  
  RESULTS
  LNCaP and LAPC4 cells both express ETA receptors. Neither the ETA or ETB antagonist altered PSA secretion, while addition of DHT, a positive control, produced a marked increase in PSA secretion.
  
  
  CONCLUSIONS
  Blockade of the ETA receptor does not affect the secretion of PSA in prostate cancer cell lines.
authors.affiliation: Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232, USA.
authors.forename: Stefana
authors.initials: S
authors.lastname: Pecher
authors.forename: Beth R
authors.initials: BR
authors.lastname: Pflug
authors.forename: Alisa K W
authors.initials: AK
authors.lastname: Brink
authors.forename: Joel B
authors.initials: JB
authors.lastname: Nelson
mesh_terms: D000077868:Atrasentan; D065130:Endothelin A Receptor Antagonists; D019332:Endothelin-1 / Q000037:antagonists & inhibitors; D006801:Humans; D008297:Male; D017430:Prostate-Specific Antigen / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000473:pathology*; D011759:Pyrrolidines / Q000494:pharmacology; D044022:Receptor, Endothelin A / Q000502:physiology*; D014407:Tumor Cells, Cultured
chemical_list: C120508:A 192621; D065130:Endothelin A Receptor Antagonists; D019332:Endothelin-1; D011759:Pyrrolidines; D044022:Receptor, Endothelin A; D017430:Prostate-Specific Antigen; D000077868:Atrasentan