Low expression of PAI-2 as a novel marker of portal vein tumor thrombosis and poor prognosis in hepatocellular carcinoma.

BACKGROUND

Plasminogen activator inhibitor (PAI)-2 was previously shown to be less frequently expressed in hepatocellular carcinoma (HCC). The present study was designed to investigate the clinical, pathological, and prognostic significance of PAI-2 expression in HCC.

METHODS

Expression of PAI-2 was detected immunohistochemically for specimens from 78 patients with HCC after hepatic resection and correlated with clinicopathological features and patient survival. Risk factors of portal vein tumor thrombosis (PVTT) were also analyzed.

RESULTS

Positive PAI-2 staining was observed in tumor and non-tumor tissues from 21 (26.9%) and 56 (71.8%) patients, respectively. Plasminogen activator inhibitor-2 negativity in tumor tissues was significantly associated with PVTT, with a high sensitivity not only in univariate analysis but also in multivariate analysis. In addition, positive PAI-2 staining was related to smaller tumor size and prolonged patient survival. The Cox regression model identified intratumoral PAI-2 staining as an independent prognosticator in patients with HCC after resection.

CONCLUSIONS

Our data demonstrated that low expression of PAI-2 serves as a novel marker of PVTT and poor prognosis in HCC.