Potential prognostic value in human breast cancer of cytosolic Nme1 protein detection using an original hen specific antibody.

The metastasis-suppressor nme gene (also called nm23), first identified in murine melanoma cells, exists as two forms in human: nme1 and nme2. However, only the lack of expression of nme1 has been related to distant metastasis appearance in human breast cancer. The aim of this work was first to raise specific antibodies to allow the analysis of Nme1 and then, with this specific tool, to evaluate the predictive value of Nme1 detection in cytosolic extracts of human breast tumours. We obtained a hen antibody that specifically reacts with Nme1 without any cross-reaction with Nme2. We analysed the expression of the protein in 59 human breast tumours and found a significant relationship between this expression and oestrogen receptor status (P<0.001). Moreover, Nme1 expression is related to metastasis-free survival (P<0.001) and survival of patients (P<0.001). The determination of Nme1 expression in primary tumours using our antibody should be an interesting predictive test of the metastasis for clinical investigations.