Increased expression of hepatoma-derived growth factor correlates with poor prognosis in human nasopharyngeal carcinoma

Aims: To examine the correlation between hepatoma-derived growth factor (HDGF) expression and clinicopathological data in nasopharyngeal carcinoma (NPC), including patient survival. Methods and results: Using real-time polymerase chain reaction (PCR) and Western blot, mRNA and protein expression of HDGF was detected in normal nasopharyngeal tissues, NPC tissues and cell lines. HDGF levels were determined further by an immunohistochemical analysis in a retrospective series consisting of 160 primary NPC tissues and 71 non-cancerous nasopharynx tissues. Overexpressed mRNA and HDGF protein was present in NPC. By immunohistochemical analysis, we found that 53.8% (86 of 160) and 19.4% (32 of 160) of NPC biopsy specimens showed higher HDGF expression of the nucleus and cytoplasm, respectively. Statistical analysis showed that the higher expression of nuclear HDGF was associated significantly with T stage (P = 0.005) and clinical stage (P = 0.038), but there was no association with lymph node (P = 0.059) or distant metastasis (P = 0.563). Patients with increased HDGF expression levels had poorer overall survival rates than those with low expression of HDGF levels (P = 0.006). Multivariate analysis revealed that high expression of nuclear HDGF was an independent prognostic indicator of patient survival. Conclusions: Increased nuclear expression of HDGF is a potential unfavourable prognostic factor for patients with NPC.