Evaluation of serum granulysin as a potential biomarker for nasopharyngeal carcinoma

•Serum GNLY level in NPC patient was significantly lower than in healthy control.•On the contrary, it's significantly higher in nasopharyngitis patient.•In NPC patients, the serum GNLY concentration was elevated in correspondence with increasing clinical stages.•There was a significant correlation between the serum GNLY levels and VCA-IgA titre or EBV DNA copy number.

BackgroundGranulysin (GNLY) is excreted from cytotoxic T lymphocytes and natural killer cells, and plays an important role in antitumor immunity. However, few studies have estimated serum GNLY concentrations in patients with nasopharyngeal carcinoma (NPC). We evaluated GNLY as a potential biomarker for NPC.MethodsSerum GNLY concentrations were measured in blood samples taken from 98 NPC patients, 56 nasopharyngitis (NPT) patients, and 99 healthy subjects. The clinical relevance of GNLY in NPC was also investigated. We also assessed the association between serum GNLY and serum immunoglobulin A antibodies against the Epstein–Barr virus (EBV) viral capsid antigen (VCA-IgA) and EBV DNA.ResultsSerum GNLY levels were significantly lower in NPC patients and significantly higher in nasopharyngitis patients compared to healthy controls. Thus, serum GNLY performs well as a biomarker for distinguishing between NPC and NPT. The serum GNLY concentration is elevated with corresponding increases in clinical stage and shows a significant correlation with VCA-IgA and EBV DNA concentration.ConclusionsSerum GNLY is closely associated with the clinical characteristics of NPC and may be a potential biomarker for NPC.