Purpose: The aim of the study was to define the prognostic role of the metastasis suppressor gene, nm23, in 106 primary ovarian cancer patients.
Patients and methods: Northern and Western blotting analysis of nm23-H1 and nm23-H2 expression were performed in a subset of ovarian tumors. Immunohistochemical analysis was performed on formalin-fixed paraffin-embedded specimens from 106 primary ovarian carcinomas by the antihuman nm23 monoclonal antibody.
Results: Northern and Western blotting analysis demonstrated a direct association between nm23-H1 and nm23-H2 levels. Moreover, an overall concordance of 86.7% between Northern blotting and immunohistochemical data was observed. Sixty-six specimens (68%) showed a positive nm23-H1 immunoreaction. The percentage of nm23-H1 positivity was higher in lymph node-negative (70%) than in lymph node-positive cases (44%) (P = .049). Moreover, the percentage of complete/partial responses to chemotherapy was higher in nm23-H1-positive (69%) than in nm23-H1-negative (44%) patients (P = .03). The percentage of epidermal growth factor receptor (EGFR) positive cases was lower in nm23-H1-positive (44%) than in nm23-H1-negative immunostained (72%) samples (P = .012). Lower ras/p21 levels (median, 1.77 absorbance units) were found in nm23-H1-positive than in nm23-H1-negative samples (median, 2.63 absorbance units) (P = .03). The 6-year progression-free survival (PFS) rate of nm23-H1-positive cases was 50% (95% confidence interval [CI], 33 to 67) versus 12% (95% CI, -2 to 26) for nm23-H1-negative patients (P = .0056). In multivariate analysis, only stage, ascites, and nm23-H1 content retained independent prognostic roles.
Conclusion: The assessment of nm23 content may provide useful information for prognostic characterization of ovarian cancer patients.