Apoptosis and the pathogenesis of endometriosis.

Apoptosis is a physiologic process that deletes unwanted cells without inducing an inflammatory reaction. Survival of endometriotic implants is associated with decreased apoptosis and an inflammatory environment. The most widely accepted theory-transplantation theory-related to the pathogenesis of endometriosis is supported by the description of abnormal survival of regurgitated endometrial cells. Eutopic endometrial cells from women with endometriosis also seem to resist apoptosis further when compared with cells from disease-free women. Several apoptotic pathways have been studied. Recent literature concerning apoptosis-related genes such as bcl-2/bax and fas/fas ligand is summarized in this article. Special emphasis is placed on sex steroid modulation and cell adhesion regulation, both relevant in early events of endometriosis.