High Expression of PGAM1 Correlates with Poor Prognosis in Patients with Pancreatic Neuroendocrine Tumors Underwent Curative Surgical Resection

Objective To identify overexpression of PGAM1 in patients with pancreatic neuroendocrine tumors （PNET） and evaluate its association with clinicopathological features and prognosis. Methods PGAM1 immunoreactivity in tumor tissues was determined by immunohistochemistry from 71 patients with PNET. The mRNA and protein levels were analyzed in cancer specimens and their corresponding para-tumor normal tissues （n=24） by qRT-PCR and Western blot, respectively. PNET patients were separated into two groups based on the immunostaining levels of PGAM1. Associations between PGAM1 levels and clinicopathological data, including patient survival, were investigated. Results Both qRT-PCR and Western blot assays showed that PGAM1 expression was increased in PNET tissues compared with normal pancreas tissues. Immunohistochemical staining of 71 cases of PNET specimens suggested that PGAM1 protein was mainly localized in the cytoplasm, and increased expression of PGAM1 was correlated with larger tumor size （t=3.65,P=0.025）. Kaplan-Meier survival curves indicated that patients with high expression of PGAM1 had a shorter overall survival （P=0.019） and poorer disease-free survival （P=0.049）. Conclusions Our results suggested that PGAM1 may serve as a potential prognostic biomarker for PNET patients.