Clinical significance of serum NM23-H1 protein in neuroblastoma.

We have previously reported that NM23 genes are overexpressed in various hematological malignancies and that serum NM23-H1 protein levels are useful for predicting patient outcomes. In this study we assessed the clinical implications of serum NM23-H1 protein on neuroblastoma. We examined serum NM23-H1 protein levels in 217 patients with neuroblastoma, including 131 found by mass-screening and 86 found clinically by an enzyme-linked immunosorbent assay, and determined the association between levels of this protein, and known prognostic factors or the clinical outcome. The serum NM23-H1 protein level was higher in neuroblastoma patients than in control children (P < 0.0001). Patients with MYCN amplification had higher serum NM23-H1 levels than those with a single copy of MYCN. Overall survival was assessed in the 86 patients found clinically, and was found to be worse in patients with higher serum MN23-H1 levels (> or = 250 ng/mL) than in those with lower levels (< 250 ng/mL; P = 0.034). The higher level of NM23-H1 was correlated with a worse outcome in patients with a single MYCN copy, or in those younger than 12 months of age. Serum NM23-H1 protein levels may contribute to predictions of clinical outcome in patients with neuroblastoma.