Expression of decoy receptor 3 in liver tissue microarrays.

BACKGROUND: Decoy receptor 3 (DcR3), a new member of the tumour necrosis factor receptor (TNFR) superfamily, is amplified and overexpressed in various cancers. We investigated the expression of DcR3 protein in liver tissue microarrays and assessed its importance in patients with hepatocellular carcinoma (HCC).
METHODS: In this retrospective study, tissue from 120 patients with HCC, 48 with tissue at least 2 cm away from the tumour (juxta-tumour tissue), 62 with cirrhosis and 23 with normal livers were studied as tissue microarrays. Immunohistochemistry was used to detect the expression of DcR3. Statistical analyses were done to assess the association between DcR3 expression and the clinicopathological features of HCC.
RESULTS: The positivity rate of DcR3 in HCC tissue was significantly higher than that in juxta-tumour tissue, cirrhosis and normal liver (p = 0.017, p < 0.0001, p < 0.0001, respectively). The positive rate of DcR3 in juxta-tumour and cirrhotic tissue both increased significantly when compared with normal liver tissue (p < 0.0001, p = 0.005, respectively). The positivity rate of DcR3 in HCC in clinical TNM stages I and II was significantly lower than that in stages III and IV (p < 0.0001). The positivity rate of DcR3 in patients without metastasis within 20 months decreased significantly compared with those with metastasis (p < 0.0001). DcR3 expression in patients with alphafoetoprotein levels > or = 400 microg/L, portal vein tumour emboli, capsular infiltration and multicentric tumour was significantly higher than in groups without these features (p = 0.021, p < 0.0001, p < 0.0001, p = 0.002, respectively).
CONCLUSION: The overexpression of DcR3 might play an important role in the pathogenesis, progression and metastases of HCC. The DcR3 gene might serve as an important molecular biological indicator in diagnosing and predicting the biological behaviour of patients with HCC.