title: Combined treatment of breast cancer cell lines with vitamin D and COX-2 inhibitors.
abstract: BACKGROUND
  Vitamin D is known for its anti-cancerogenous potential. Prostaglandin E2 (PGE2) is a proliferation and inflammation activating agent. The production of PGE2 is dependent on the activity of cyclooxygenase-2 (COX-2). A link between vitamin D and PGE2 metabolism was recently shown.
  
  
  METHODS
  In MDA-MB-231 and MCF-7 breast cancer cell lines we investigated the influence of calcitriol and the COX-2 inhibitor celecoxib regarding cell growth via MTT test, as well as on the protein and mRNA expression of COX-2 using western blot and qRT-PCR.
  
  
  RESULTS
  The proliferation of MCF-7 and MDA-MB-231 was inhibited by both calcitriol and the COX-2 inhibitor celecoxib and even stronger by their combination. Moreover, calcitriol inhibited the COX-2 protein expression in MDA-MB-231, as well as the COX-2 mRNA expression in both cell lines.
  
  
  CONCLUSIONS
  The combination of calcitriol and celecoxib demonstrated a cooperative growth-inhibiting effect in breast cancer cell lines.
authors: Department of Gynecology and Obstetrics, Agaplesion Markus Hospital, Frankfurt am Main, Germany.
authors: Marc
authors: M
authors: Thill
authors: Department of Gynecology and Obstetrics, University of Lübeck, Lübeck, Germany.
authors: Kathrin
authors: K
authors: Reichert
authors: Department of Gynecology and Obstetrics, University of Lübeck, Lübeck, Germany.
authors: Alena
authors: A
authors: Woeste
authors: Department of Gynecology and Obstetrics, University of Lübeck, Lübeck, Germany.
authors: Stephan
authors: S
authors: Polack
authors: Department of Gynecology and Obstetrics, University of Lübeck, Lübeck, Germany.
authors: Dorothea
authors: D
authors: Fischer
authors: Department of Gynecology and Obstetrics, University of Lübeck, Lübeck, Germany.
authors: Friederike
authors: F
authors: Hoellen
authors: Department of Gynecology and Obstetrics, University of Lübeck, Lübeck, Germany.
authors: Achim
authors: A
authors: Rody
authors: Department of Gynecology and Obstetrics, Helios Hospital Krefeld, Krefeld, Germany.
authors: Michael
authors: M
authors: Friedrich
authors: Department of Gynecology and Obstetrics, University of Lübeck, Lübeck, Germany frank.koester@uksh.de.
authors: Frank
authors: F
authors: Köster
mesh_terms: D001943:Breast Neoplasms / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology; D045744:Cell Line, Tumor; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism; D052246:Cyclooxygenase 2 Inhibitors / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D014807:Vitamin D / Q000627:therapeutic use*
chemical_list: D052246:Cyclooxygenase 2 Inhibitors; D014807:Vitamin D; D051546:Cyclooxygenase 2
keywords: Vitamin D; breast cancer; celecoxib; cyclooxygenase-2