THE LOCALIZATION OF P34(CDC2) IN THE CELLS OF NORMAL, HYPERPLASTIC, AND MALIGNANT EPITHELIAL AND LYMPHOID-TISSUES OF THE ORAL CAVITY

The expression of p34(cdc2) has been examined in normal, hyperplastic, and malignant oral epithelia and lymphoid tissues. Four monoclonal an tibodies mere prepared against Xenopus p34(cdc2), three of which react specifically with human p34(cdc2) and with p33(cdk2). These produced similar patterns of staining in both fixed and frozen sections of huma n material, Staining occurred mainly in the proliferative compartments of normal and hyperplastic tissues, In normal oral epithelia, parabas al and basal cells were the most strongly stained, with lighter cytopl asmic staining in lower prickle cells, In tonsillar germinal centres, a high proportion of cells was stained, with fewer positive cells in i nterfollicular zones, a distribution in keeping with the known pattern of cell proliferation, In normal cells, the intracellular location of p34(cdc2) was cytoplasmic until early prophase, but in oral squamous cell carcinomas and lymphomas, it was located in both cytoplasm and nu cleus during interphase and a larger fraction of cells was positive th an in the equivalent normal tissues. Higher-grade neoplasms showed bot h a higher intensity of staining and a higher proportion of p34(cdc2)- positive cells.