Increased expression of COX-2 in nontumor liver tissue is associated with shorter disease-free survival in patients with hepatocellular carcinoma.
Recent studies have shown increased levels of cyclooxygenase-2 (COX-2) in a variety of human malignancies including hepatocellular carcinoma (HCC), but little is known about the prognostic value of COX-2 in HCC or its associated nontumor liver tissue. We examined the expression of COX-2 protein by immunohistochemistry in 53 patients with HCCs whose corresponding nontumor tissues were hepatitis C virus-related chronic hepatitis (n = 21) and cirrhosis (n = 32). Samples of nine histologically normal livers and eight precancerous dysplasias were also analyzed. The level of COX-2 increased from normal liver to chronic hepatitis to cirrhosis. The majority of cirrhotic livers (81%) displayed marked COX-2 expression. In dysplasias, COX-2 expression was mainly moderate or strong (88%). In HCC, 17% of samples displayed a high COX-2 expression, and 37% of samples expressed COX-2 at a moderate level. Concordant results were obtained with reverse transcription-PCR and Western blot analyses. Clinicopathological survey indicated a significant correlation between COX-2 expression and differentiated carcinoma (P = 0.019). Although there was no correlation between COX-2 expression in HCC and prognosis, a striking difference was found between COX-2 expression in nontumor tissue and shorter disease-free survival (P = 0.0132). Moreover, high COX-2 expression in nontumor tissue was significantly correlated with the presence of active inflammation (P < 0.0001). The present findings suggest that COX-2 expression in nontumor tissue may play a positive role in relapse of HCC after surgery.
Kondo
M
M
Department of Surgery II, Osaka University Medical School, Japan.
Yamamoto
H
H
Nagano
H
H
Okami
J
J
Ito
Y
Y
Shimizu
J
J
Eguchi
H
H
Miyamoto
A
A
Dono
K
K
Umeshita
K
K
Matsuura
N
N
Wakasa
K
K
Nakamori
S
S
Sakon
M
M
Monden
M
M
D015153:Blotting, Western; D006528:Carcinoma, Hepatocellular / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D051546:Cyclooxygenase 2; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000096:biosynthesis* / Q000235:genetics; D008099:Liver / Q000201:enzymology* / Q000473:pathology / Q000821:virology; D008113:Liver Neoplasms / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D008297:Male; D008565:Membrane Proteins; D008875:Middle Aged; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
D007527:Isoenzymes; D008565:Membrane Proteins; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases