Immunoreactivity for cadherins, HGF/SF, met, and erbB-2 in pleural malignant mesotheliomas

Aims: To assess the immunoreactivity of malignant mesotheliomas for N- and E-cadherins, hepatocyte growth factor/scatter factor (HGF/SF) and the tyros ine kinase receptors, met and erbB-2. Methods and results: Pleural malignant mesotheliomas were stained using a s tandard indirect immunoperoxidase method applied to paraffin sections. Mali gnant mesotheliomas were immunoreactive for N-cadherin (26/29; 90%), met (2 9/29; 100%) and erbB-2 (28/29; 97%). Focal immunoreactivity was present for E-cadherin in epithelioid or mixed tumours (14/25; 56%), and for HGF/SF (9 /24; 38%). Conclusions: Expression of N-cadherin supports the diagnosis of malignant m esothelioma and use of appropriate antibodies would be a useful addition to a diagnostic antibody panel. Focal staining for E-cadherin does not exclud e mesothelioma. Signalling pathways mediated via met and erbB-2 may play a role in the growth and spread of malignant mesotheliomas.