The Spontaneously Occurred Apoptosis in Squamous Carcinoams of the Uterine Cervix

Kim, Chan Hwan; Park, Kwan Kyu; Kwon, Kun Young; Lee, Sang Sook; Chang, Eun Sook

Abstract

The apoptosis, a distinctive type of individual cell necrosis, has been considered to play a complementary but opposite role to mitosis in the regulation of animal cell populations. It can be initiated or inhibited by a variety of environmental stimuli, physiologically and pathologically. Apoptosis seems to appear in either non-neoplastic or neoplastic tissues, even malignant tumors in the state of untreatment or irradiation. This study was carried out to investigate the spontaneous occurrence of apoptosis in squamous carcinomas of the uterine cervix and its mechanisms. Light microscopically, noted were the condensation and fragmentation of individual tumor cells with formation of apoptotic bodies that were frequently phagocytosed by nearby intact tumor cells. They were commonly seen in the neighbourhood of coagulative necrosis. Electron microscopically (TEM and SEM), noted were nuclear condensation, margination toward the nuclear membrane and fragmentation of membrane-bounded apoptotic bodies that were well preserved. The intracellular apoptotic bodies were phagosomes and reduced to electron-dense lysosomal residual bodies. The conclusion obtained was as follow: Apoptosis was found in all cases of squamous carcinoma of the uterine cervix, of which the frequency was higher in tumors of poor differentiation than those of well to moderate differentiation. The process of the apoptosis is considered to pass through the step of formation of the apoptotic bodies, phagocytosis by adjoining tumor cells or histiocytes, and then degradation as lysosmal residual bodies.