NM23 EXPRESSION IN HUMAN BREAST-CANCER - CORRELATION WITH CELL-PROLIFERATION (S-PHASE) AS OBSERVED WITH A DOUBLE-LABELING IMMUNOCYTOCHEMICAL-AUTORADIOGRAPHIC TECHNIQUE

In 51 unselected breast cancer samples, a double-labeling immunocytoch emical technique was utilized to observe the phenotypic expression of the nm23 gene during S-phase. The feasibility of the method was confir med by comparison with routine evaluations for both thymidine-labeling index and nm23 (p<0.001). No correlation was found between the two pa rameters in the overall series or when subgroups regarding menopausal status, nodal involvement, tumor size, hormone receptor content were c onsidered. Tumors with a higher nuclear grade showed a significant cor relation only with TLI (p=0.02). A trend for an inverse relationship b etween the two parameters was noted but was not statistically signific ant. A significant association between TLI and nm23 expression was fou nd by Chi-square test using median values as cut-off. Our data based o n morphological and in situ observations do not confirm a correlation between nm23 and cell proliferation, even if this correlation cannot b e completely excluded. Multicentric trials of high power with these sa me techniques are still necessary to definitely establish the prognost ic role of nm23 in breast cancer.