nm23 Protein expression in larynx cancer and the relationship with metastasis.

The nm23 gene, which encodes nucleoside diphosphate (NDP) kinase, is proposed as a metastatic suppressor gene and has been demonstrated to correlate inversely with metastatic potential in several tumours. To elucidate the role of nm23 in larynx carcinomas, we examined using immunohistochemistry the expression of the nm23 protein in matched sets of primary tumours and metastatic lymph nodes. nm23 Protein was expressed in all the carcinomas as well as in non-neoplastic larynx mucosa. Overexpression of nm23 protein was found in the majority of primary tumours compared with corresponding normal mucosa, while decreased expression was associated with poor differentiation and distant metastasis and/or recurrence. No significant difference in age, sex and stage was found between primary tumours with high and low nm23 protein expression. These results suggest that decreased nm23 protein expression may play a role in metastasis and/or recurrence in larynx cancer and therefore could be used as a prognostic factor.