APOPTOSIS IN HUMAN ENDOMETRIAL AND ENDOMETRIOTIC TISSUES

Apoptosis has recently been proposed to represent programmed cell deat h. Several investigations have revealed that uterine endometrium in ma mmals can be regulated by apoptosis. However, apoptosis may be less li kely to occur in human eutopic endometrium. On the other hand, immunor eactivity of Bcl-2 that may serve a regulatory function in protecting from undergoing apoptosis was observed in uterine endometrial glandula r cells in the proliferative phase through to the early secretory phas e. In endometriotic tissues, although apoptosis was detected in all th e samples from ovarian endometriosis, it was indicated in only a few t issues from adenomyosis. Bcl-2 was negative in almost all samples from ovarian endometriosis, whereas it was positive in all adenomyotic tis sues from cases in the proliferative phase, but in none of tissues fro m cases in the secretory phase. Thus, ovarian endometriosis can be dis criminated from adenomyosis based on the existence of apoptosis though both represent a type of ectopic endometrial tissue, and the pathogen esis or condition of the cells may be different between ovarian endome triosis and adenomyosis.