title: Prostaglandin metabolising enzymes and PGE2 are inversely correlated with vitamin D receptor and 25(OH)2D3 in breast cancer.
abstract: BACKGROUND
  Breast cancer is associated with inflammatory processes based on an up-regulation of cyclooxygenase-2 (COX-2) expression. The antiproliferative effects of calcitriol (1,25(OH)(2)D(3)) mediated via the vitamin D receptor (VDR) render vitamin D a promising target in breast cancer therapy. First data suggest a correlation between vitamin D and prostaglandin metabolism.
  
  
  METHODS
  We determined the expression of VDR, COX-2, 15-PGDH and the prostaglandin receptors EP(2)/EP(4) in normal and malignant breast tissue by real-time PCR and Western blot analysis, as well as 25(OH)(2)D(3) and PGE(2) plasma levels from healthy and breast cancer patients.
  
  
  RESULTS
  Significantly higher COX-2, lower VDR and lower EP(2) and EP(4) receptor protein levels in the malignant tissue and a significantly lower 15-PGDH protein level in normal breast tissue were detected. Breast cancer patients older than 45 years, diagnosed and sampled in the winter time had significantly lower 25(OH)(2)D(3) and higher PGE(2) serum levels.
  
  
  CONCLUSIONS
  The inverse correlation between VDR and both COX-2 and 15-PGDH, as well as between PGE(2) and 25(OH)(2)D(3) levels, suggests a possible link between VDR-associated target genes and prostaglandin metabolism.
authors.affiliation: Department of Obstetrics and Gynecology, University Hospital Schleswig-Holstein, Campus Luebeck, Luebeck, Germany. marc.thill@uk-sh.de
authors.forename: Marc
authors.initials: M
authors.lastname: Thill
authors.forename: Dorothea
authors.initials: D
authors.lastname: Fischer
authors.forename: Friederike
authors.initials: F
authors.lastname: Hoellen
authors.forename: Katharina
authors.initials: K
authors.lastname: Kelling
authors.forename: Christine
authors.initials: C
authors.lastname: Dittmer
authors.forename: Solveig
authors.initials: S
authors.lastname: Landt
authors.forename: Darius
authors.initials: D
authors.lastname: Salehin
authors.forename: Klaus
authors.initials: K
authors.lastname: Diedrich
authors.forename: Michael
authors.initials: M
authors.lastname: Friedrich
authors.forename: Steffi
authors.initials: S
authors.lastname: Becker
mesh_terms: D001943:Breast Neoplasms / Q000378:metabolism*; D002117:Calcitriol / Q000378:metabolism*; D002277:Carcinoma / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D006911:Hydroxyprostaglandin Dehydrogenases / Q000378:metabolism; D008875:Middle Aged; D011379:Prognosis; D011453:Prostaglandins / Q000378:metabolism*; D018167:Receptors, Calcitriol / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014018:Tissue Distribution
chemical_list: D011453:Prostaglandins; D018167:Receptors, Calcitriol; D006911:Hydroxyprostaglandin Dehydrogenases; C035859:15-hydroxyprostaglandin dehydrogenase; D002117:Calcitriol; D015232:Dinoprostone