Prognostic relevance of cyclooxygenase-2 (COX-2) expression in Chinese patients with prostate cancer.
Cyclooxygenase-2 (COX-2), an inducible isoform of cyclooxygenase, has been reported to be correlated with tumorigenesis, tumor progression and metastasis. The present study was designed to investigate the clinicopathological and prognostic significance of COX-2 in Chinese patients with prostate cancer. Firstly, RT-PCR and Western blot assays were performed to detect the expression of COX-2 mRNA and protein in prostate cancer cell lines and 20 tissue samples (tumor or corresponding non-tumor). Next, immunohistochemistry was performed to detect the expression of COX-2 protein in 88 prostate cancer tissue samples. Finally, the correlation between COX-2 expression and clinicopathological factors and patient survival was evaluated. We found that the expression levels of COX-2 mRNA and protein showed significant difference among four prostate cancer cell lines. Moreover, the levels of COX-2 mRNA and protein were significantly higher in prostate cancer tissues than in corresponding non-tumor tissues. COX-2 staining was positive in the cytoplasm of prostate cancer cells. High-COX-2 expression was correlated with the Gleason score (P=0.009), tumor stage (P=0.012), and lymph-node status (P=0.036). Furthermore, patients with high-COX-2 expression showed lower disease-free (P=0.014) and overall survival (P=0.047) rates than those with low-COX-2 expression. Univariate and multivariate analyses suggested that the status of COX-2 protein expression was an independent prognostic indicator for patients' survival. Taken together, higher COX-2 protein expression might provide an independent prognostic marker for Chinese patients with prostate cancer who have undergone surgery.
Bin
Wu
W
Department of Urology, Xijing Hospital, Fourth Military Medicine University, Shannxi Province, PR China.
He
Wang
W
Feng
Zhang
Z
Xiangdong
Lu
L
Yong
Chen
C
Lele
Kou
K
Hongbin
Zhang
Z
Honglin
Guo
G
D014408:Biomarkers, Tumor / Q000032:analysis* / Q000096:biosynthesis / Q000235:genetics; D015153:Blotting, Western; D002681:China; D051546:Cyclooxygenase 2 / Q000032:analysis* / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000201:enzymology* / Q000235:genetics / Q000601:surgery; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015996:Survival Rate; D014407:Tumor Cells, Cultured
D014408:Biomarkers, Tumor; D012333:RNA, Messenger; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human