title: Relationship between the expression of cyclooxygenase 2 and MDR1/P-glycoprotein in invasive breast cancers and their prognostic significance.
abstract: BACKGROUND
  Recent reports suggest that expression of the cyclooxygenase 2 (COX-2) enzyme may up-regulate expression of MDR1/P-glycoprotein (MDR1/P-gp), an exponent of resistance to cytostatic drugs. The present study aimed at examining the relationship between the expression of COX-2 and of MDR1/P-gp in a group of breast cancer cases.
  
  
  METHODS
  Immunohistochemical reactions were performed using monoclonal antibodies against COX-2 and MDR1/P-gp on samples originating from 104 cases of primary invasive breast cancer.
  
  
  RESULTS
  COX-2-positive cases were shown to demonstrate higher expression of MDR1/P-gp (P < 0.0001). The studies also demonstrate that COX-2 expression was typical for cases of a higher grade (P = 0.01), a shorter overall survival time (P < 0.0001) and a shorter progression-free time (P < 0.0001). In the case of MDR1/P-gp, its higher expression characterised cases of a higher grade (P < 0001), with lymph node involvement (P < 0001), and shorter overall survival (P < 0.0001) and progression-free time (P < 0.0001).
  
  
  CONCLUSIONS
  Our studies confirmed the unfavourable prognostic significance of COX-2 and MDR1/P-gp. We also document a relationship between COX-2 and MDR1/P-gp, which suggests that COX-2 inhibitors should be investigated in trials as a treatment supplementary to chemotherapy of breast cancers.
authors.affiliation: Institute of Pathology, Charité Campus Mitte, Berlin, Germany.
authors.forename: Pawel
authors.initials: P
authors.lastname: Surowiak
authors.forename: Verena
authors.initials: V
authors.lastname: Materna
authors.forename: Rafal
authors.initials: R
authors.lastname: Matkowski
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Szczuraszek
authors.forename: Jan
authors.initials: J
authors.lastname: Kornafel
authors.forename: Andrzej
authors.initials: A
authors.lastname: Wojnar
authors.forename: Marek
authors.initials: M
authors.lastname: Pudelko
authors.forename: Manfred
authors.initials: M
authors.lastname: Dietel
authors.forename: Carsten
authors.initials: C
authors.lastname: Denkert
authors.forename: Maciej
authors.initials: M
authors.lastname: Zabel
authors.forename: Hermann
authors.initials: H
authors.lastname: Lage
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000201:enzymology / Q000401:mortality / Q000473:pathology*; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D018450:Disease Progression; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D011379:Prognosis; D016019:Survival Analysis; D013997:Time Factors
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D051546:Cyclooxygenase 2