Decreased Progesterone Receptor B/A Ratio in Endometrial Cells by Tumor Necrosis Factor-Alpha and Peritoneal Fluid from Patients with Endometriosis

PURPOSE: Progesterone resistance is thought to be a major factor that contributes to progression of endometriosis. However, it is not clear what causes progesterone resistance in endometriosis. This study aimed to assess whether cytokines or peritoneal fluid can affect progesterone receptor (PR) expression in endometrial cells and to verify whether PR expression is reduced in endometriosis. MATERIALS AND METHODS: The PR-B/A ratio was measured via real-time polymerase chain reaction after in vitro culture, in which endometrial cells were treated with either tumor necrosis factor-alpha (TNF-α), interleukin-1 beta, or peritoneal fluid obtained from women with advanced-stage endometriosis. Immunohistochemistry was performed to compare PR-B expression between eutopic and ectopic endometrial tissues from women with and without advanced-stage endometriosis. RESULTS: The PR-B/A ratio was significantly decreased by treatment with either TNF-α (p=0.011) or peritoneal fluid from women with advanced-stage endometriosis (p=0.027). Immunoreactivity of PR-B expression was significantly lower during the secretory phase than during the proliferative phase in endometrial tissues from control subjects (p<0.001). PR-B expression was significantly reduced in the eutopic endometrium (p=0.031) and ovarian endometrioma (p=0.036) from women with advanced-stage endometriosis compared with eutopic endometrium tissues from control subjects. CONCLUSION: Progesterone resistance in endometriosis may be caused by proinflammatory conditions in the pelvic peritoneal microenvironment.

Decreased Progesterone Receptor B/A Ratio in Endometrial Cells by Tumor Necrosis Factor-Alpha and Peritoneal Fluid from Patients with Endometriosis

PURPOSE: Progesterone resistance is thought to be a major factor that contributes to progression of endometriosis. However, it is not clear what causes progesterone resistance in endometriosis. This study aimed to assess whether cytokines or peritoneal fluid can affect progesterone receptor (PR) expression in endometrial cells and to verify whether PR expression is reduced in endometriosis. MATERIALS AND METHODS: The PR-B/A ratio was measured via real-time polymerase chain reaction after in vitro culture, in which endometrial cells were treated with either tumor necrosis factor-alpha (TNF-α), interleukin-1 beta, or peritoneal fluid obtained from women with advanced-stage endometriosis. Immunohistochemistry was performed to compare PR-B expression between eutopic and ectopic endometrial tissues from women with and without advanced-stage endometriosis. RESULTS: The PR-B/A ratio was significantly decreased by treatment with either TNF-α (p=0.011) or peritoneal fluid from women with advanced-stage endometriosis (p=0.027). Immunoreactivity of PR-B expression was significantly lower during the secretory phase than during the proliferative phase in endometrial tissues from control subjects (p<0.001). PR-B expression was significantly reduced in the eutopic endometrium (p=0.031) and ovarian endometrioma (p=0.036) from women with advanced-stage endometriosis compared with eutopic endometrium tissues from control subjects. CONCLUSION: Progesterone resistance in endometriosis may be caused by proinflammatory conditions in the pelvic peritoneal microenvironment.

Increased expression of nuclear factor kappa-B p65 subunit in adenomyosis

OBJECTIVE: Nuclear factor kappa-B (NF-κB) is a critical proinflammatory regulator that has been suggested to play a pivotal role in the pathogenesis and pathophysiology of endometriosis. In the present study, we aimed to evaluate whether the expression of NF-κB p65 subunit is increased in the eutopic endometrium and/or in the adenomyosis nodule of women with adenomyosis. METHODS: Thirty-three women with histologically confirmed adenomyosis after laparoscopic or transabdominal hysterectomy were recruited. Women with carcinoma in situ of uterine cervix without evidence of adenomyosis or endometriosis (n=32) served as controls. Formalin-fixed, paraffin-embedded archival tissues were sectioned and immunostained utilizing a monoclonal anti-human NF-κB p65 subunit antibody, and the immunoreactivity of NF-κB p65 subunit was compared between women with and without adenomyosis. RESULTS: The immunoreactivities of both the nuclear and the cytoplasmic NF-κB p65 subunit were significantly increased in the stromal cells in the eutopic endometrium as well as in the adenomyosis nodule of women with adenomyosis compared with controls, respectively. The nuclear expression of NF-κB p65 subunit was significantly higher in the glandular cells in the eutopic endometrium as well as the adenomyosis nodule of women with adenomyosis compared with controls, respectively. CONCLUSION: The expression of NF-κB p65 is increased in the eutopic endometrium and adenomyosis nodule of women with adenomyosis, which strongly suggest that NF-κB plays a critical role in the pathogenesis and/or pathophysiology of adenomyosis.