Abstract
To investigate the cell proliferative ability of uterine cervical dysplasia and carcinoma in situ (CIS), the numbers of argyrophilic nucleolar organizer regions (AgNORs) and MIB-1-positive cells were determined in 76 precancerous and cancerous lesions. When AgNORs and MIB-1-positive cells were counted from the basal to superficial layers, the greater the degree of dysplasia, the higher the AgNOR number and MIB-1 labeling index. However, neither measurement differed significantly between severe dysplasia and CIS. The number of MIB-1-positive cells increased in the superficial layer as histologic grade increased. When only cells nearest to the epithelial-stromal junction (the basal layer) were examined, MIB-1-positive cells were rare in nondysplastic and mildly dysplastic epithelium and increased in number in grades above moderate dysplasia. Moreover, both AgNOR number and MIB-1 labeling index differed significantly between severe dysplasia and CIS. These results suggest that as dysplasia progresses, prolif erative cells first appear from the parabasal layer to the superficial layer and that cells of the basal layer enter the cell cycle later than do adjacent cells of the parabasal layer. Moreover, we believe that dysplasia and CIS differ in the number of basal layer cells that enter the cell cycle.
