Semiquantitative immunoblot analysis of nm23-H1 and-H2 isoforms in adenocarcinomas of the lung: Prognostic significance

Total amounts of nm23 protein and relative revels of H1 and H2 isoforms wer e studied in 27 fresh-frozen samples of pulmonary adenocarcinoma and adjace nt non-neoplastic tissues that were obtained at surgery. Semiquantitative i mmunoblotting with a monoclonal antibody (Pan-242) against nm23 protein dem onstrated both isoforms, recognized as 20.5 kDa for H1 and 18.5 kDa for H2, to be present in all cases. Both H1 and H2 levels in neoplastic tissues we re higher than in the corresponding non-neoplastic samples. Expression of H 2 was usually greater than of H1. The H2/H1 ratio varied from 1.9 to 14.1 ( mean value 5.2) in non-neoplastic tissues and 1.0-5.9 (mean value 2.5) in n eoplastic tissues, although this ratio did not correlate with any prognosti c factor like tumor size, nodal status or distant metastasis (TNM tumor sta ge). Ht and H2 levels were significantly lower (mean values 4.3 and 2.4) in well-differentiated than in moderately and poorly differentiated adenocarc inomas (8.3 and 3.0) (P<0.03 and P<0.05, respectively). These data indicate that Hf and H2 isoform levels correlate with histological differentiation, but not the metastatic potential or stage of pulmonary adenocarcinoma.