Co-overexpression of cyclooxygenase-2 and microsomal prostaglandin E synthase-1 adversely affects the postoperative survival in non-small cell lung cancer.
BACKGROUND
Cyclooxygenase (COX)-2 and microsomal prostaglandin E synthase (mPGES)-1 have been found to be overexpressed in non-small cell lung cancer (NSCLC). The aim of this study was to investigate the expression profiles of COX-2 and mPGES-1 and their correlation with the clinical characteristics and survival outcomes in patients with resected NSCLC.


RESULTS
Seventy-nine paired adjacent normal-tumor matched samples were prospectively procured from patients undergoing surgery for NSCLC. The protein levels of COX-2 and mPGES-1 were assessed by Western blot analysis. Overexpression in the tumor sample was defined as more than twofold increase in protein expression compared with the corresponding adjacent normal tissue. Co-overexpression of COX-2 and mPGES-1 were further confirmed by immunohistochemistry. COX-2 was overexpressed in 58% and mPGES-1 in 70% of the tumor samples (p < 0.0001). Co-overexpression of mPGES-1 and COX-2 was noted in 43%, and they were unrelated to each other (p = 0.232). Co-overexpression of both proteins was significantly associated with less tumor differentiation (p = 0.046), tumor size larger than 5 cm (p = 0.038), and worse survival status during the follow-up (p = 0.036). Multivariate analysis showed that in addition to overall stage, co-overexpression of both proteins adversely affected the overall (hazard ratio, 2.40; p = 0.045) and disease-free survivals (hazard ratio, 2.27; p = 0.029).


CONCLUSIONS
Overexpression of either COX-2 or mPGES-1 is common but unrelated in NSCLC. Co-overexpression of both COX-2 and mPGES-1 adversely affects postoperative overall and disease-free survivals.
Wu
Yu-Chung
YC
Division of Thoracic Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan.
Su
Li-Jen
LJ
Wang
Hao-Wei
HW
Jeff Lin
Chien-Fu
CF
Hsu
Wen-Hu
WH
Chou
Teh-Ying
TY
Huang
Chi-Ying F
CY
Lu
Chia-Li
CL
Hsueh
Chung-Tsen
CT
D000230:Adenocarcinoma / Q000378:metabolism* / Q000401:mortality / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015153:Blotting, Western; D018287:Carcinoma, Large Cell / Q000378:metabolism* / Q000401:mortality / Q000601:surgery; D002289:Carcinoma, Non-Small-Cell Lung / Q000378:metabolism* / Q000401:mortality / Q000601:surgery; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D019746:Intramolecular Oxidoreductases / Q000378:metabolism*; D008175:Lung Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000601:surgery; D008297:Male; D008875:Middle Aged; D018307:Neoplasms, Squamous Cell / Q000378:metabolism* / Q000401:mortality / Q000601:surgery; D011379:Prognosis; D011446:Prospective Studies; D000071876:Prostaglandin-E Synthases; D015996:Survival Rate
D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D019746:Intramolecular Oxidoreductases; C000605862:PTGES protein, human; D000071876:Prostaglandin-E Synthases