Relationship between the expression of cyclooxygenase 2 and MDR1/P-glycoprotein in invasive breast cancers and their prognostic significance.
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.
Surowiak
Pawel
P
Institute of Pathology, Charité Campus Mitte, Berlin, Germany.
Materna
Verena
V
Matkowski
Rafal
R
Szczuraszek
Katarzyna
K
Kornafel
Jan
J
Wojnar
Andrzej
A
Pudelko
Marek
M
Dietel
Manfred
M
Denkert
Carsten
C
Zabel
Maciej
M
Lage
Hermann
H
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
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D051546:Cyclooxygenase 2