[Correlation of cyclooxygenase-2 expression to P-glycoprotein expression in B-cell non-Hodgkin's lymphoma].
OBJECTIVE
The overexpression of P-glycoprotein (P-gp) plays an important role in the chemoresistance of relapsed lymphoma. It is up-regulated in a cyclooxygenase-2 (COX-2)-dependent manner. This study was to observe the expression and correlation of COX-2 and P-gp in B-cell non-Hodgkin's lymphoma (B-NHL), and to investigate their correlations to clinicopathologic features of B-NHL.


METHODS
The expression of COX-2 and P-gp in 43 specimens of naive B-NHL and 27 specimens of relapsed B-NHL were detected by SP immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR).


RESULTS
The positive rates of COX-2 and P-gp were significantly lower in naive B-NHL than in relapsed B-NHL (23.3% vs. 74.1%, 11.6% vs. 70.4%, P<0.01). COX-2 expression was positively correlated to P-gp expression in relapsed B-NHL (r=0.998, P<0.01). The positive rates of COX-2 and P-gp were significantly higher in aggressive B-NHL than in indolent B-NHL (64.3% vs. 10.7%, P=0.002; 52.4% vs. 7.1%, P=0.012).


CONCLUSIONS
COX-2 and P-gp are highly expressed in relapsed B-NHL, and they may play a role in tumor metastasis of B-NHL.
Li
Bin
B
Department of Oncology, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, PR China. luoxiao4132@sina.com.cn
Zhong
Mei-Zuo
MZ
Tang
Tao-Fu
TF
Liu
Wei
W
Huang
Jin
J
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism*; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D016393:Lymphoma, B-Cell / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local; D020133:Reverse Transcriptase Polymerase Chain Reaction
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human