Expression of interferon receptors in pancreatic cancer: identification of a novel prognostic factor.

Abstract

Interferons (IFNs) are known to have antiproliferative and immunoregulatory activities that are modulated through specific cellular-surface ligands, known as IFN-alpha, -beta, and -gamma receptors. The presence of these receptors and their impact on survival in patients with pancreatic cancer has not been determined. Slides were prepared from 46 patients with pancreatic adenocarcinoma. Immunohistochemistry (IHC) was used subsequently to determine the expression of IFN-alpha/beta receptor-chain 2 (IFNalpha/betaR) and IFN-gamma receptor-chain 1 (IFNgammaR). The correlation among IFN-receptor expression, characteristics of neoplasms, and overall patient survival were determined analytically. The IHC performed for pancreatic adenocarcinoma demonstrated a high IFNalpha/betaR expression in 4% (2/46) of patients, moderate expression in 20% (9/46), and faint or no expression in 76% (35/46). IHC confirmed a high expression of IFNgammaR in 52% (24/46) of patients, moderate expression in 35% (16/46), and faint or no expression in the remaining 13% (6/46). A clinicopathologic survey failed to demonstrate any significant correlation between IFNalpha/betaR and IFNgammaR expression with regard to size of neoplasm, vascular or perineural invasion, lymph node metastases, or stage of disease. Kaplan-Meier survival analyses demonstrated a survival advantage in those patients whose neoplasms expressed moderate to high IFNalpha/betaR expression, compared with those with faint or no IFNalpha/betaR expression (22 vs 13 months; P = .012, log-rank test). The expression of IFNgammaR, however, had no impact on patient survival (20 months vs 17 months; P = .66, log-rank test). The IFNalpha/betaR is an independent prognostic factor in patients with pancreatic cancer.