G-CSF associates with neurogenesis and predicts prognosis and sensitivity to chemotherapy in pancreatic ductal adenocarcinoma

BACKGROUND: Recent studies demonstrated that granulocyte colony-stimulating factor (G-CSF), regularly used for the prevention of neutropenia, is engaged in cancer progression. However, the role of G-CSF in pancreatic ductal adenocarcinoma (PDAC) is not clear. The aim of the present study was to investigate the expression and prognostic value of G-CSF in patients with PDAC. MATERIALS AND METHODS: The localization and expression of G-CSF in PDAC were examined by immunohistochemistry (IHC). The analysis of the levels of G-CSF in plasma was evaluated using ELISA kit. The correlation between G-CSF expression and patients’ survival was assessed by Kaplan–Meier analysis. RESULTS: In IHC specimens, G-CSF was discovered predominantly in the cell cytoplasm and expressed in most of PDAC, while in plasma, the systemic level of G-CSF is no different between normal patients and pancreatic cancer patients. In 100 PDAC cases with IHC, patients with grades 2 and 3 were defined as the high expression group (41 patients, 41%), and those with grades 0 and 1 as the low expression group (59 patients, 59%). Significant correlation was noted between high G-CSF expression and neural invasion (P = 0.042) or early recurrence (P < 0.001). G-CSF appeared to be an independent adverse prognostic factor (hazard ratio = 1.774, 95% confidence interval 1.150–2.737, P = 0.010) in addition to N stage (P = 0.002). Specifically, adjuvant chemotherapy consisting of gemcitabine prolongs survival of patients with high G-CSF expression (median survival time 14 months vs 7.5 months). Morphologically, high G-CSF expression cells demonstrate the association with neurogenesis. CONCLUSION: High expression of G-CSF is a prognostic marker and an indicator to chemotherapy response in PDAC.