An epigenetic disorder may cause aberrant expression of aromatase gene in endometriotic stromal cells.

Objective: To examine the molecular basis of aromatase expression in stromal cell culture from endometriotic chocolate cysts.

Design: Prospective study.

Setting: Department of Obstetrics and Gynecology and Department of Biosignaling, Tottori University, Yonago Japan.

Peroxisome proliferator-activated receptor-gamma ligand reduced tumor necrosis factor-alpha-induced interleukin-8 production and growth in endometriotic stromal cells.

Objective: To evaluate the influence of peroxisome proliferator-activated receptor-gamma (PPAR gamma) ligand (pioglitazone) on tumor necrosis factor-alpha (TNF-alpha)-induced interleukin-8 (IL-8) expression in endometriotic stromal cells (ESCs) and on proliferation of ESCs.

Design: Prospective study.

Setting: Department of Obstetrics and Gynecology, Tottori University Hospital, Yonago, Japan.

Apoptosis and endometriosis.

Apoptosis plays a critical role in maintaining tissue homeostasis and represents a normal function to eliminate excess or dysfunctional cells. Accumulated evidence suggest that apoptosis helps to maintain cellular homeostasis during the menstrual cycle by eliminating senescent cells from the functional layer of the uterine endometrium during the late secretory and menstrual phase of the cycle. BCL-2 family and Fas/FasL system have been extensively studied in human endometrium and endometriotic tissues.

Aberrant expression of keratinocyte growth factor receptor in ovarian surface epithelial cells of endometrioma.

Ovarian surface epithelial cells (OSEs) are considered to be the common source of endometrioma and epithelial ovarian cancer. The present study reveals that keratinocyte growth factor receptor (KGFR) messenger RNA was expressed in OSEs of endometriomas but not in those of normal ovaries, suggesting that autocrine KGF/KGFR and paracrine fibroblast growth factor 10/KGFR signaling loops may be involved with the proliferation in OSEs of endometrioma.