nm23-H1 expression in nasopharyngeal carcinoma: Correlation with clinical outcome

The expression levels of nm23-HI mRNA and its protein in human nasopharyngeal carcinoma (NPC) were detected to clarify the relationship between nm23-HI and metastasis and prognosis of patients with NPC. nm23-HI mRNA expression in fresh tissues from 78 patients with NPC was investigated by in situ hybridization and RT-PCR. Routine labeling streptavidinbiotin immuno-histochemistry with the nm23-HI murine monoclonal antibody was employed to study the expression of nm23-HI protein in paraffin-embedded specimens from 231 patients with NPC treated in our hospital. The clinical pathologic data and results of follow-up were collected. Comparisons between expression of nm23-HI protein or mRNA and clinical outcome were performed using the chi(2) test. Multivariate prognostic analyses were performed by the Cox regression model. We found that nm23-HI-negative tumors were associated with a higher incidence of lymphnode metastasis (84.2%) than nm23-HI-positive ones (32.8%, p < 0.01), The distant metastasis and loco-regional recurrence rates in the nm23-HI-negative group were 55.8% and 31.68%, respectively but only 17.2% and 11.5%, respectively, in the nm23-HI-positive group (p < 0.01). A significant association was found between expression of nm23-HI protein and prognosis (P < 0.01). Expression of nm23-HI protein indicated favorable prognosis, suggesting that the absence of nm23-HI protein expression was significantly associated with lymph-node metastasis, recurrence and distant metastasis in NPC. Expression of the nm23-HI gene may be valuable for assessing the prognosis of NPC. (C) 1998 Wiley-Liss, Inc.