Myoungseok Han

Di-(2-ethylhexyl)-phthalate induces oxidative stress in human endometrial stromal cells in vitro

Di-(2-ethylhexyl)-phthalate (DEHP) accumulates in the environment, and its exposure is possibly associated with endocrine-related disease in women of reproductive age. The effects of DEHP on human endometrial cells are unknown. We treated human endometrial stromal cells with 10, 100, and 1000 pmol of DEHP and measured reactive oxygen species (ROS) generation, expression levels of antioxidant enzymes, alteration of MAPK/NF-κB signaling and hormonal receptors. DEHP increased reactive oxygen species (ROS) generation and decreased expression of superoxide dismutase (SOD), glutathione peroxidase (GPX), heme oxygenase (HO), and catalase (CAT). By DEHP exposure, p-ERK/p-p38 and NF-κB mediated transcription was increased. Additionally, DEHP induced estrogen receptor-α (ER-α) expression in a dose-dependent manner. This study shows the need for future mechanistic studies of oxidative stress, MAPK/NF-κB signaling, and ER-α as molecular mediators of DEHP-associated endometrial stromal cell alterations, which may be associated with the development of endocrine-related disease such as endometriosis.

Bilateral Ovarian Pregnancy After in Vitro Fertilization and Embryo Transfer in a Patient with Tubal Factor Infertility

Primary ovarian pregnancy is very rare event after natural pregnancy or assisted reproductive technology (ART) procedures. Although there are a few reports about unilateral ovarian pregnancy after in vitro fertilization and embryo transfer (IVF-ET), there has been no report about bilateral ovarian pregnancy. Moreover, it is difficult to diagnose an ovarian pregnancy following in vitro fertilization and embryo transfer because of enlarged ovary, fluid collection in pelvic cavity, and its low incidence. We present a case of a patient who underwent IVF-ET due to tubal factor infertility, but the patient developed bilateral ovarian pregnancy and was performed both ovarian wedge resection through laparotomy.

Recurrence of ovarian endometrioma after second-line, conservative, laparoscopic cyst enucleation

OBJECTIVE We sought to evaluate the cumulative recurrence rate of endometrioma after a second-line, conservative, laparoscopic endometriotic cyst enucleation and to analyze the factors that influence the recurrence of endometrioma. STUDY DESIGN A multicenter retrospective cohort study was performed at 3 gynecologic surgery centers from January 2000 through December 2010. Patients surgically treated by laparoscopic enucleation of endometriotic cysts on 2 previous occasions were selected. All patients were aged <40 years at the time of the primary surgery and were followed up for at least 6 months. Endometrioma recurrence was considered when transvaginal sonography indicated a cystic mass with a diameter of ≥20 mm. RESULTS In total, 183 patients were followed up for 33.2 ± 27.7 months (range, 6-121 months). Thirty-eight (20.8%) patients experienced recurrence after the second-line surgery and 24 (13.1%) patients underwent a third surgery. The median time to recurrence was 24 ± 3.36 months (SEM) (range, 3-72 months). The cumulative recurrence rates per patient at 12, 24, 36, and 60 months after the second-line surgery were 7.7%, 13.7%, 21.3%, and 37.5%, respectively. After multivariate analysis and analysis of covariance, the revised American Fertility Society score and stage were significantly higher in patients who experience a third recurrence of endometrioma. CONCLUSION The cumulative recurrence rate of ovarian endometrioma after a second-line surgery appears to be correlated to the duration of follow-up. Severe endometriosis at the second-line surgery seems to be a factor associated with a high recurrence risk. Physicians should be cautious with regard to the postoperative management of these patients.

Biomonitoring of Lead, Cadmium, Total Mercury, and Methylmercury Levels in Maternal Blood and in Umbilical Cord Blood at Birth in South Korea

With rising concerns of heavy metal exposure in pregnancy and early childhood, this study was conducted to assess the relationship between the lead, cadmium, mercury, and methylmercury blood levels in pregnancy and neonatal period. The study population included 104 mothers and their children pairs who completed both baseline maternal blood sampling at the second trimester and umbilical cord blood sampling at birth. The geometric mean maternal blood levels of lead, cadmium, total mercury, and methylmercury at the second trimester were 1.02 ± 1.39 µg/dL, 0.61 ± 1.51 µg/L, 2.97 ± 1.45 µg/L, and 2.39 ± 1.45 µg/L, respectively, and in the newborns, these levels at birth were 0.71 ± 1.42 µg/dL, 0.01 ± 5.31 µg/L, 4.44 ± 1.49 µg/L, and 3.67 ± 1.51 µg/L, respectively. The mean ratios of lead, cadmium, total mercury, and methylmercury levels in the newborns to those in the mothers were 0.72, 0.04, 1.76, and 1.81, respectively. The levels of most heavy metals in pregnant women and infants were higher in this study than in studies from industrialized western countries. The placenta appears to protect fetuses from cadmium; however, total mercury and methylmercury were able to cross the placenta and accumulate in fetuses.

Antiproliferative and apoptotic effect of epigallocatechin-3-gallate on Ishikawa cells is accompanied by sex steroid receptor downregulation

Endometrial cancer is a significant malignancy in developed countries. Unopposed estrogen stimulation is considered as an important risk factor for endometrial cancer. Epigallocathechin-3-gallate (EGCG), biological active component of green tea, inhibits cancer cell proliferation. However, it is unknown whether EGCG has anticancer effects on endometrial cancer and what the molecular mechanism(s) are. We investigated the anticancer effects of EGCG on a human endometrial adenocarcinoma cell line (Ishikawa cells) with or without 17β-estradiol (E2) treatment. Cell proliferation assay was performed using 3-(4,5-dimethylthiaxol-2-yi)-2,5-diphenyltetraxolium bromide (MTT). The cell cycle was determined by flow cytometry and real-time analysis of cyclin and cdk genes. The apoptosis was measured by Annexin V-PI staining and real-time analysis of bcl-2, Bax and caspase genes. The MAPK signal, Akt and caspase-3 were determined by immunoblotting. Decreased estrogen and progesterone receptor expression was observed in EGCG-treated Ishikawa cells, and decreased MAPK signals and phospho-Akt were observed as well. EGCG caused the arrest of cells in the G0/G1 phase of the cell cycle. This compound interfered with Akt activation and MAPK signals, and increased apoptosis signals leading to a controlled caspases, Bcl-2, Bax genes and protein expression. Taken together, EGCG inhibits cell proliferation and induces apoptosis through Akt and MAPK signals. These findings suggest that EGCG may exert growth-inhibitory and apoptosis-inducing effects on endometrial cancer cells, accompanied by decreased estrogen and progesterone receptor. EGCG may have future clinical implications with respect to the development of novel approaches as an adjuvant therapy in endometrial cancer.

Effects of letrozole on proliferation and apoptosis in cultured leiomyoma cells treated with prostaglandin E2

OBJECTIVE The objective was to determine the direct effect of letrozole on the proliferation and apoptosis of cultured leiomyoma cells co-treated with prostaglandin E(2) (PGE(2)). STUDY DESIGN Leiomyoma cells were obtained from three groups of patients who had undergone hysterectomy due to leiomyoma. Percentages of antiproliferative cells were evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and apoptosis was assessed with sub-G1 cell counts by flow cytometry and Western blot analysis. RESULTS Combined treatment with 100 microM letrozole and 10 microM PGE(2) for 48 h resulted in a significantly lower viability rate (25.9+/-4.5%) and an increased cell death rate (31.6+/-4.4%) than groups treated with letrozole or PGE(2) alone. However, after adding 10nM estradiol to the combined treatment group, the cell viability rate was restored (75.1+/-7.7%) and the cell death rate was decreased (10.5+/-3.1%). Increased caspase-3 expression was found in the letrozole and PGE(2) combined treatment group, but not in the group in which estradiol was added. CONCLUSION The present results demonstrate that letrozole inhibits growth and induces apoptosis of leiomyoma cells by blocking the aromatase up-regulated by PGE(2) treatment. These findings support the need for further investigation of aromatase inhibitors as a medical treatment option in leiomyoma.

Cyclooxygenase-2 Inhibitor, Celecoxib, Inhibits Leiomyoma Cell Proliferation Through the Nuclear Factor κB Pathway

Our aim was to investigate whether celecoxib, a cyclooxygenase 2 (COX-2) inhibitor, decreases the in vitro proliferation of leiomyoma cells if the inflammatory pathway is blocked. Menstruation is an inflammation of uterus that produces cytokines and prostanoids, but the inflammatory mechanism underlying the growth of leiomyoma remains unexplained. Using in vitro cultures of leiomyoma cells obtained from 5 patients who underwent hysterectomy, cell proliferation, inflammatory signaling, transcription factors, growth factors, and extracellular matrix were examined by (4,5-dimethylthiaxol-2-yi)-2,5-diphenyltetraxolium bromide assay, immunoblotting, and quantitative polymerase chain reaction. Prostaglandin E2 was used to induce menstruation-like condition in the cells. We found that celecoxib inhibited COX-2 through the expression of nuclear factor κB in the cells. Celcoxib also decreased the gene expression of interleukin 6, tumor necrosis factor α, collagen A, fibronectin, platelet-derived growth factor, epidermal growth factor, and transforming growth factor β. In conclusion, the present study indicated that celecoxib could inhibit leiomyoma cell proliferation through blocking the inflammatory pathway that is probably one of the mechanisms underlying its pathogenesis.

Uterine Lipoleiomyoma in Peri or Postmenopausal Women

Lipoleiomyoma is an uncommon neoplasm of the uterus, composed of smooth muscles intermixed with mature adipocytes. These tumors are considered a benign variant of uterine leiomyomas. Herein, we report six cases of lipoleiomyoma experienced in our institution from January 2005 to March 2015. The patients ranged in age from 45 to 70 years; the etiology may be related to estrogen deficiency occurring after menopausal transition. Except for one lipoleiomyoma in the broad ligament, all others were found in the uterine corpus. The presenting symptoms were nonspecific, and most cases were incidentally diagnosed during surgery for other reasons. We performed preoperative imaging studies, including abdominal and pelvic computed tomography and magnetic resonance imaging. Preoperatively, four patients were diagnosed as having a pelvic mass and one patient was diagnosed as having a right ovarian mature teratoma. In one case, we found a gynecologic malignancy (cervical cancer 1A1). Histologically, there was no gross or microscopic contiguity between the lipoleiomyoma and the malignancy. Lipoleiomyomas seem to have a benign clinical course. In our study, there were no recurrences of or deaths attributed to the lipoleiomyomas during a mean follow-up period of 16.17 ± 23.80 months.

Inhibitory effects of androstenedione on endometrial cells: implications for poor reproductive outcome among women with androgen excess

OBJECTIVE Androstenedione (A4) is an androgen that can be metabolized by aromatase to estrone, but the effects of A4 on endometrial cell proliferation either as an androgen or via conversion to estrogens are unknown. The aim of this study was to investigate A4 effects on Ishikawa cells in culture. STUDY DESIGN Ishikawa cells were treated with increasing concentrations of A4 (0-1000 pmol) for 4 days. Cell proliferation was measured by the (4,5-dimethylthiaxol-2-yi)-2,5-diphenyltetraxolium bromide (MTT) assay. Apoptosis was analyzed through Annexin-V/propidium iodide (PI) staining and flow cytometry: 17β-hydroxy steroid dehydrogenase type 1 (17β-HSD1) and aromatase mRNA expression was measured by reverse transcription-polymerase chain reaction (RT-PCR). Western blotting was used to detect cell signaling expressions of Akt/MAPK. RESULTS A4 treatment (1 nM) decreased cell proliferation and increased apoptosis, as demonstrated by MTT and flow cytometry or related gene expression. The cellular responses induced by A4 treatment were mediated by activation of the Akt and MAPK signaling pathway. Treatment had no effect on 17β-HSD1 and aromatase expression. CONCLUSION A4 treatment induced growth inhibition and apoptosis of Ishikawa cells through activation of the Akt/MAPK pathway. Effects of A4 on Ishikawa cells occurred in the absence of increased 17β-HSD1 and aromatase expression. These results imply that women with excessive androgen, such as polycystic ovary syndrome, experience poor reproductive outcomes through androgen-regulated mechanisms.

Bisphenol A modulates inflammation and proliferation pathway in human endometrial stromal cells by inducing oxidative stress

Bisphenol A (BPA) has been implicated in altered human reproductive function. The oxidative stress or change of inflammatory signaling may appear a key factor in the biological changes of the human endometrium. Using MTT assay we assessed BPA mediated modulation of oxidative stress and inflammation responses in human endometrial stromal cells (ESCs). According to the results, reactive oxygen species (ROS) generation was highest upon exposure to 1000 pmol BPA. Increased mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) were demonstrated. Gene expression and release of inflammatory cytokines were increased. Upon BPA exposure, elevated estrogen receptor (ER)-α expression levels in ESCs correlated with changes in oxidative stress, inflammatory gene expression and signal changes in cellular proliferation signaling. These findings support that BPA induces oxidative stress and activates inflammatory signals in cultured ESCs via ER-α. Together, this result may provide insight into the association between BPA exposure and endometrium-related disorders.