Clinical significance of B7-H1 and B7-1 expressions in pancreatic carcinoma

Abstract

Background: Cancer cells develop mechanisms to evade immune cells and achieve progression. Aberrant B7-H1 and B7-1 expressions may help pancreatic carcinoma (PC) cells escape immune attack; these molecules can be considered as prognostic markers for patients with PC who have undergone radical resection.

Methods: We recruited 81 patients who had undergone radical surgical resection for PC between 1999 and 2007. To investigate the prognostic factors, we evaluated the B7-H1 and B7-1 protein expressions in the tissue specimens of these 81 patients by immunohistochemistry and analyzed the clinical and pathological features of these specimens.

Results: B7-H1 was expressed mainly in pancreatic islets, and no B7-1 expression was detected in normal pancreatic tissues. B7-H1 and B7-1 expressions were higher in pancreatic carcinoma tissues than in normal pancreatic tissues (P < 0.05). B7-H1 and B7-1 significantly correlated with the pathological grade and tumor-node-metastasis (TNM) stage, respectively (P < 0.05). Furthermore, B7-1-negative or B7-H1-positive statuses were prognostic indicators of poor disease-specific survival (P < 0.05), but only combined B7-1/B7-H1 expression retained the prognostic potential after adjusting by Cox proportional hazards regression models (P < 0.05).

Conclusions: Both B7-H1 and B7-1 are expressed in PC; these molecules are important markers for PC progression. Furthermore, combined B7-1/B7-H1 expression can serve as an independent prognostic marker for PC.