Evaluation of the clinical performance of noninvasive prenatal testing at a Japanese laboratory.

AIM: We aimed to evaluate the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of noninvasive prenatal testing (NIPT) in high-risk pregnant women. METHODS: Pregnant women who underwent GeneTech NIPT, the most commonly used NIPT in Japan, between January 2015 and March 2019, at Japan NIPT Consortium medical sites were recruited for this study. The exclusion criteria were as follows: pregnant women with missing survey items, multiple pregnancy/vanishing twins, chromosomal abnormalities in the fetus other than the NIPT target disease, and nonreportable NIPT results. Sensitivity and specificity were calculated from the obtained data, and maternal age-specific PPV and NPV were estimated. RESULTS: Of the 45 504 cases, 44 263 cases fulfilling the study criteria were included. The mean maternal age and gestational weeks at the time of procedure were 38.5 years and 13.1 weeks, respectively. Sensitivities were 99.78% (95% confidence interval [95% CI]: 98.78-99.96), 99.12% (95% CI: 96.83-99.76), and 100% (95% CI: 88.30-100) for trisomies 21, 18, and 13, respectively. Specificities were more than 99.9% for trisomies 21, 18, and 13, respectively. Maternal age-specific PPVs were more than 93%, 77%, and 43% at the age of 35 years for trisomies 21, 18, and 13, respectively. CONCLUSION: The GeneTech NIPT data showed high sensitivity and specificity in the detection of fetal trisomies 21, 18, and 13 in high-risk pregnant women, and maternal age-specific PPVs were obtained. These results could provide more accurate and improved information regarding NIPT for genetic counseling in Japan.

Development and Practical Test of Quality Indicators for Palliative Care in Patients With Chronic Heart Failure.

BACKGROUND: Palliative care is highly relevant for patients with heart failure (HF), and there is a need for quantitative information on quality of care. Accordingly, this study aimed to develop a set of quality indicators (QIs) for palliative care of HF patients, and to conduct a practical pilot measurement of the proposed QIs in clinical practice.Methods and Results:We used a modified Delphi technique, a consensus method that involves a comprehensive literature review, face-to-face multidisciplinary panel meeting, and anonymous rating in 2 rounds. A 15-member multidisciplinary expert panel individually rated each potential indicator on a scale of 1 (lowest) to 9 (highest) for appropriateness. All indicators receiving a median score ≥7 without significant disagreement were included in the final set of QIs. Through the consensus-building process, 35 QIs were proposed for palliative care in HF patients. Practical measurement in HF patients (n=131) from 3 teaching hospitals revealed that all of the proposed QIs could be obtained retrospectively from medical records, and the following QIs had low performance (<10%): "Intervention by multidisciplinary team", "Opioid therapy for patients with refractory dyspnea", and "Screening for psychological symptoms". CONCLUSIONS: The first set of QIs for palliative care of HF patients was developed and could clarify quantitative information and might improve the quality of care.

Qualitative investigation of the factors that generate ambivalent feelings in women who give birth after receiving negative results from non-invasive prenatal testing.

BACKGROUND: Women who receive negative results from non-invasive prenatal genetic testing (NIPT) may find that they later have mixed or ambivalent feelings, for example, feelings of accepting NIPT and regretting undergoing the test. This study aimed to investigate the factors generating ambivalent feelings among women who gave birth after having received negative results from NIPT. METHODS: A questionnaire was sent to women who received a negative NIPT result, and a contents analysis was conducted focusing on ambivalent expressions for those 1562 women who responded the questionnaire. The qualitative data gathered from the questionnaire were analyzed using the N-Vivo software package. RESULTS: Environmental factors, genetic counseling-related factors, and increased anticipatory anxiety, affected the feeling of ambivalence among pregnant women. Furthermore, pregnant women desired more information regarding the detailed prognosis for individuals with Down syndrome and living with them and/or termination, assuming the possibility that they were positive. CONCLUSIONS: Three major interrelated factors affected the feeling of ambivalence in women. Highlighting and discussing such factors during genetic counseling may resolve some of these ambivalences, thereby enhancing the quality of decisions made by pregnant women.

Survey of Palliative Sedation at End of Life in Terminally Ill Heart Failure Patients　- A Single-Center Experience of 5-Year Follow-up.

BACKGROUND: Little is known about palliative sedation in terminally ill heart failure (HF) patients.Methods and Results:We retrospectively reviewed terminally ill HF patients who received palliative sedation from September 2013 to August 2018. Among 95 terminally ill HF patients, 25 were prescribed dexmedetomidine and 12 were prescribed midazolam at the end of life. Richmond Agitation-Sedation Scale was significantly reduced (P<0.01), but blood pressure and heart rate were unaltered after treatment in both the dexmedetomidine and midazolam groups. CONCLUSIONS: Prescription of dexmedetomidine and/or midazolam might be feasible in selected terminally ill HF patients.

Classification of factors involved in nonreportable results of noninvasive prenatal testing (NIPT) and prediction of success rate of second NIPT.

OBJECTIVE: To evaluate the reasons for nonreportable cell-free DNA (cfDNA) results in noninvasive prenatal testing (NIPT), we retrospectively studied maternal characteristics and other details associated with the results. METHODS: A multicenter retrospective cohort study in pregnant women undergoing NIPT by massively parallel sequencing (MPS) with failed cfDNA tests was performed between April 2013 and March 2017. The women's data and MPS results were analyzed in terms of maternal characteristics, test performance, fetal fraction (FF), z scores, anticoagulation therapy, and other details of the nonreportable cases. RESULTS: Overall, 110 (0.32%) of 34 626 pregnant women had nonreportable cfDNA test results after an initial blood sampling; 22 (20.0%) cases had a low FF (<4%), and 18 (16.4%) cases including those with a maternal malignancy, were found to have altered genomic profile. Approximately half of the cases with nonreportable results had borderline z score. Among the women with nonreportable results because of altered genomic profile, the success rate of retesting using a second blood sampling was relatively low (25.0%-33.3%). Thirteen (11.8%) of the women with nonreportable results had required hypodermic heparin injection. CONCLUSIONS: The classification of nonreportable results using cfDNA analysis is important to provide women with precise information and to reduce anxiety during pregnancy.

Current status of non-invasive prenatal testing in Japan.

AIM: The purpose of this study was to report the 3-year experience of a nationwide demonstration project to introduce non-invasive prenatal testing (NIPT) of maternal plasma for aneuploidy, and review the current status of NIPT in Japan. METHODS: Tests were conducted to detect aneuploidy in high-risk pregnant women, and adequate genetic counseling was provided. The clinical data, test results, and pregnancy outcomes were recorded. We discuss the problems of NIPT on the basis of published reports and meta-analyses. RESULTS: From April 2013 to March 2016, 30 613 tests were conducted at 55 medical sites participating in a multicenter clinical study. Among the 30 613 women tested, 554 were positive (1.81%) and 30 021 were negative (98.1%) for aneuploidy. Of the 289, 128, and 44 women who tested positive for trisomies 21, 18, and 13, respectively, and underwent definitive testing, 279 (96.5%), 106 (82.8%), and 28 (63.6%) were determined to have a true-positive result. For the 13 481 women with negative result and whose progress could be traced, two had a false-negative result (0.02%). The tests were performed on the condition that a standard level of genetic counseling be provided at hospitals. CONCLUSION: Here, we report on the 3-year nationwide experience with NIPT in Japan. It is important to establish a genetic counseling system to enable women to make informed decisions regarding prenatal testing. Moreover, a welfare system is warranted to support women who decide to give birth to and raise children with chromosomal diseases.

A survey on awareness of genetic counseling for non-invasive prenatal testing: the first year experience in Japan.

The purpose of this study is to summarize the results from a survey on awareness of genetic counseling for pregnant women who wish to receive non-invasive prenatal testing (NIPT) in Japan. As a component of a clinical study by the Japan NIPT Consortium, genetic counseling was conducted for women who wished to receive NIPT, and a questionnaire concerning both NIPT and genetic counseling was given twice: once after pre-test counseling and again when test results were reported. The responses of 7292 women were analyzed. They expressed high satisfaction with the genetic counseling system of the NIPT Consortium (94%). The number of respondents who indicated that genetic counseling is necessary for NIPT increased over time. Furthermore, they highly valued genetic counseling provided by skilled clinicians, such as clinical geneticists or genetic counselors. The vast majority (90%) responded that there was sufficient opportunity to consider the test ahead of time. Meanwhile, women who received positive test results had a poor opinion and expressed a low-degree satisfaction. We confirmed that the pre-test genetic counseling that we conducted creates an opportunity for pregnant women to sufficiently consider prenatal testing, promotes its understanding and has possibilities to effectively facilitate informed decision making after adequate consideration. A more careful and thorough approach is considered to be necessary for women who received positive test results.

Rationale and Design of a Multicenter Trial on Exploratory Analysis of the Effects of Advance Care Planning Guided by the Prediction Program of Heart Failure Prognosis on Quality of Life in Patients With Heart Failure　- ACQUAINT-Trial.

Background: Preplanning of care is necessary for patients with endstage heart failure (HF), but advance care planning (ACP) before the loss of a patient's comprehensive capacity is not yet routine for the public or the medical community. The challenge in accurately predicting a patient's prognosis is a strong barrier to implementing ACP. To address this problem, several models for risk stratification have been proposed and are available in clinical settings. Methods and Results: We randomized the procedure to provide estimated patient survival information to attending physicians and then assessed whether there was a change in (1) the frequency of ACP initiation occurred (physician-side evaluation), and/or (2) the patients' quality of life, including mental state (patient-side evaluation). Conclusions: This multicenter, open-label, single-blinded randomized clinical trial aims to assess the hypothesis that providing information on the estimated survival of a patient to the attending physicians will improve the frequency of ACP initiation and quality of life in patients with HF.

miR-196b targets c-myc and Bcl-2 expression, inhibits proliferation and induces apoptosis in endometriotic stromal cells.

STUDY QUESTION: What is the global expression pattern of microRNAs (miRNAs) in endometriotic stromal cells and is miR-196b involved in the pathogenesis of endometriosis? SUMMARY ANSWER: Several miRNAs are aberrantly expressed in endometriotic cyst stromal cells (ECSCs), including miR-196b whose expression is repressed in endometriotic stromal cells. WHAT IS KNOWN ALREADY: Although, histologically, endometriotic tissues and normal proliferative endometrium are similar, a number of distinct molecular differences have been reported to date. The anti-apoptotic and excessive proliferative properties of endometriotic cells are considered to be involved in the development and progression of endometriosis. STUDY DESIGN AND SIZE DURATION: ECSCs and normal endometrial stromal cells (NESCs) were isolated from ovarian endometriotic tissues and eutopic endometrial tissues, respectively and compared. PARTICIPANTS/MATERIALS, SETTING AND METHODS: Aberrantly expressed miRNAs in ECSCs were identified by a global miRNA microarray technique. The roles of miR-196b in ECSC proliferation, apoptosis, and c-myc and B-cell lymphoma/leukemia (Bcl)-2 mRNA expression were investigated with precursor hsa-miR-196b transfection. The methylation status of the miR-196b gene in ECSCs and the effect of a DNA demethylating agent on miR-196b expression were also examined. MAIN RESULTS AND THE ROLE OF CHANCE: miRNA microarray analysis identified eight down-regulated miRNAs (including miR-196b) and four up-regulated miRNAs in ECSCs. Compulsory expression of miR-196b directed the inhibition of proliferation and the induction of apoptosis in ECSCs. miR-196b was found to suppress c-myc and Bcl-2 mRNA expression in ECSCs, and there was a significant correlation between miR-196b and HOXA10 expression in ECSCs and NESCs. The miR-196b gene was hypermethylated in ECSCs when compared with NESCs, and the treatment with a DNA demethylating agent restored the expression of miR-196b in ECSCs. LIMITATIONS AND REASONS FOR CAUTION: miRNA expression profiles were investigated only in the stromal component of ectopic and eutopic endometrium samples. In addition to miR-196b, the roles of other miRNAs aberrantly expressed in ECSCs should be examined. WIDER IMPLICATIONS OF THE FINDINGS: The present findings suggest that aberrant miRNA expression plays an important role in the pathogenesis of endometriosis as a part of epigenetic mechanisms, that expression of miR-196b in ECSCs is repressed by DNA hypermethylation of the miR-196b gene and this repression may be involved in the development of proliferative and anti-apoptotic characteristics of endometriosis. STUDY FUNDING: This work was supported in part by Grants-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (no. 20591920 to K.N. and no. 23592407 to H.N.) and The Uehara Memorial Foundation (to K.N.).

Thrombin-induced chemokine production in endometrial stromal cells.

BACKGROUND: In order to investigate the regulation of chemokines [interleukin-8 (IL-8), growth-regulated oncogene (GRO)α, monocyte chemoattractant protein-1 (MCP-1)) induced by thrombin in endometrial stromal cells (ESCs), the effects of thrombin, a protease activated receptor (PAR)-1 antagonist (PPACK), mitogen-activated protein kinase kinase inhibitor (U0126), phospholipase C inhibitor (U-73122), an antagonist of the intracellular InsP3 receptor (2-aminoethoxy-diphenylborate (2-APB)] and a protein kinase C inhibitor (GF-109203X) on the production of chemokines by ESCs were evaluated. METHODS: ESCs from eight endometrial specimens in the secretory phase were cultured and incubated for 24h with thrombin and PPACK, U0126, U-73122, 2-APB or GF-109203X. The levels of IL-8, GROα and MCP-1 in the culture medium were measured by means of ELISA. The activation of MAP kinase was detected by western blot analysis using anti-phosphorylated MAP kinase (ERK1/2) antibody. RESULTS: Following stimulation by thrombin, the production of IL-8, GROα and MCP-1 increased significantly in a dose-dependent manner. PPACK, U0126, U-73122, 2-APB or GF-109203X suppressed the increases in production of IL-8, GROα and MCP-1 induced by thrombin (P < 0.001, P <0.001 and P <0.001, respectively). MAP kinase activities were induced by treatment with thrombin, and were suppressed by PPACK, U0126, U-73122, 2-APB or GF-109203X. CONCLUSIONS: Our results suggest that thrombin stimulates the production of IL-8, GROα and MCP-1 via PAR-1 by a mechanism involving the MAP kinase system. The increases in IL-8, GROα and MCP-1 may contribute to the maintenance of implantation involving leukocyte chemotaxis.

Application of the histone deacetylase inhibitors for the treatment of endometriosis: histone modifications as pathogenesis and novel therapeutic target.

BACKGROUND: Accumulating evidence suggests that various epigenetic aberrations play definite roles in the pathogenesis of endometriosis. We investigated the histone acetylation status in endometriosis and the application of the histone deacetylase inhibitors (HDACIs) for the treatment of endometriosis. METHODS: The levels of acetylated histones in the endometriotic cyst stromal cells (ECSCs) and normal endometrial stromal cells (NESCs) were evaluated. The effects of the HDACIs on cell proliferation, the cell cycle, apoptosis of ECSCs and NESCs, and the expression of genes related to these cellular events were investigated. The effects of HDACIs on histone acetylation in chromatin of the promoter region of the cell cycle regulatory genes in ECSCs were also investigated. RESULTS: The acetylated histone levels were significantly lower in ECSCs than in NESCs (P < 0.025). HDACIs inhibited cell proliferation and induced cell cycle arrest and apoptosis of ECSCs. The effects of HDACIs on NESCs were marginal or weak. These HDACIs induced an accumulation of acetylated histones in total cellular chromatin and in the promoter regions of the p16(INK4a), p21(Waf1/Cip1), p27(Kip1) and cycle checkpoint kinase 2 genes in ECSCs. HDACIs induced the protein expression of these cell cycle regulators and suppressed the protein expression of Bcl-2 and Bcl-X(L) in ECSCs. CONCLUSIONS: The present findings demonstrated that aberrant histone modifications are present in endometriosis and that HDACIs reactivated epigenetically silenced genes, resulting in the suppression of cell proliferation, induction of cell cycle arrest and apoptosis of ECSCs. HDACIs are therefore promising agents for the treatment of endometriosis.

Cadmium chloride induces the expression of metallothionein mRNA by endometrial stromal cells and amnion-derived (WISH) cells.

BACKGROUND: Metallothionein (MT) is known to bind to metals with high affinity. The potential for MT-1 mRNA expression in endometrial stromal cells (ESC) and amniotic cells in response to cytokines and cadmium chloride (CdCl(2)) was evaluated. METHODS: Human ESC were cultured and treated with interleukin-1α, 12-O-tetradecanoylphobol 13-acetate (TPA), forskolin, transforming growth factor-ß, and CdCl(2). Amnion-derived (WISH) cells were also cultured and treated with the same reagents. The levels of MT mRNA were evaluated by Northern blot analysis in ESC and WISH cells. RESULTS: In response to treatment with CdCl(2) (0.01-10 µM), the expression of MT mRNA markedly increased in ESC and WISH cells in a dose-dependent manner. On the other hand, the expression of MT mRNA did not increase after treatment with interleukin-1α (1 nM), TPA (10 nM), forskolin (1 µM) or transforming growth factor-ß (1 nM) in these cells. CONCLUSION: These findings indicate that MT expression in ESC and WISH cells is sensitive to the CdCl(2) concentration, which is known to be evaluated in cigarette smokers. The present results suggest that increased levels of MT may affect metal metabolism at the feto-maternal interface.

Aberrant DNA methylation status of endometriosis: epigenetics as the pathogenesis, biomarker and therapeutic target.

Endometriosis, a common, benign, estrogen-dependent disease affecting 3-10% of women of reproductive age, is characterized by the ectopic growth of endometrial tissue that is found primarily in the peritoneum, ovaries and rectovaginal septum. Recently, endometriosis has been alternatively described as an immune disease, a genetic disease and a disease caused by exposure to environmental factors, in addition to its usual description as a hormonal disease. In addition, accumulating evidence suggests that various epigenetic aberrations play definite roles in the pathogenesis of endometriosis. Epigenetic alterations reported to date in endometriosis include the genomic DNA methylation of progesterone receptor-B, E-cadherin, homeobox A10, estrogen receptor-ß, steroidogenic factor-1 and aromatase. Aberrant expression of DNA methyltransferases, which attach a methyl group to the 5-carbon position of cytosine bases in the CpG island of the promoter region and silence the corresponding gene expression, has also been demonstrated in endometriosis. This review summarizes the recent studies on the aberrant DNA methylation status and aberrant expression of DNA methyltransferases, which regulate DNA methylation, in endometriosis. We also discuss the recent information on the diagnostic and therapeutic implications of epigenetic alterations occurring in endometriosis.

Experience of morphine therapy for refractory dyspnea as palliative care in advanced heart failure patients.

BACKGROUND: In the field of palliative care, morphine is known to be effective for alleviating dyspnea in cancer patients. However, little is known regarding the safety and efficacy of morphine therapy for refractory dyspnea as palliative care in advanced heart failure (HF) patients. METHODS: We retrospectively reviewed consecutive advanced HF patients who were referred to the Palliative Care Team at our institution and administered morphine for refractory dyspnea during hospitalization between September 2013 and December 2018. We investigated the details of morphine usage, vital signs, an 11-point quantitative symptom scale, and adverse events at baseline, 24 h, and 72 h after the start of treatment. RESULTS: Morphine was administered for refractory dyspnea in 43 advanced HF patients [mean age: 73.5 years, male: 28 (65%), New York Heart Association functional class IV: 43 (100%), median left ventricular ejection fraction: 25%, median B-type natriuretic peptide level: 927 pg/ml, concurrent intravenous inotrope: 33 (77%)]. Median initial dose of morphine was 5 mg/day in both oral and intravenous administration and median duration of administration was 5 days. Significant decreases in an 11-point quantitative symptom scale [7 (5, 9) vs. 2 (1, 6); p < 0.01, (data available in 8 patients)] and respiratory rate (22.2 ± 6.1 vs. 19.7 ± 5.2 breaths per minute; p < 0.01) were observed 24 h after the start of morphine administration. Meanwhile, oxygen saturation, blood pressure, and heart rate were not significantly altered after treatment (NS). Common adverse events were delirium (18%) and constipation (8%); however, no lethal adverse event definitely related to morphine therapy occurred during treatment. CONCLUSIONS: This single-center retrospective study revealed the clinical practice of morphine therapy and suggested that morphine therapy might be feasible for refractory dyspnea as palliative care in advanced HF patients.

Development and validation of support tools for advance care planning in patients with chronic heart failure.

BACKGROUND: Advance care planning (ACP) is recommended as part of the management of patients with heart failure (HF). AIMS: To develop and validate ACP support tools for patients with HF. METHODS: An ACP support tool was developed based on a systematic literature review. A multi-center, prospective before and after study was conducted to evaluate the usefulness of the support tool. This study included 21 patients with HF, 11 patients formed the control group and 10 patients were part of the intervention group who received ACP from medical staff using the ACP support tools developed for this study. Participants of the study were surveyed about their experience of ACP using a 6-point Likert scale. FINDINGS: All of the healthcare professionals (n=9) involved in the study found the ACP tool useful and about 90% of patients considered the support tool useful. The score for 'the patient did not feel anxious about the future after receiving ACP discussion' was significantly higher (3.5 [3.0, 4.0] vs 2.0 [1.0, 3.0]; P=0.04) in the intervention group that used the ACP tool. CONCLUSION: ACP support tools are useful to manage patients with HF and could enable effective ACP without increasing patient anxiety.

Fetal cell-free DNA fraction in maternal plasma for the prediction of hypertensive disorders of pregnancy.

OBJECTIVE: The purpose of this study is to compare the fetal fractions during non-invasive prenatal testing (NIPT) in singleton pregnancies according to gestational age and maternal characteristics to evaluate the utility of this parameter for the prediction of pregnancy complications including gestational diabetes mellitus (GDM) and hypertensive disorders of pregnancy (HDP). STUDY DESIGN: This study was a multicenter prospective cohort study. The present data were collected from women whose NIPT results were negative. The relationships between the fetal fractions and the gestational age, maternal weight and height, and incidences of miscarriage, preterm delivery, and pregnancy complications including GDM, HDP and placental abruption were assessed. RESULTS: A total of 5582 pregnant women with verified NIPT negative results were registered in the study. The demographic characteristics of the study populations were statistically analyzed, and the women with HDP tended to have a low fetal fraction in samples taken during early gestation. The area under the curve (AUC) in a receiver operating characteristic curve (ROC) analysis was 0.608 for women with HDP. CONCLUSION: A low fetal fraction on NIPT might be correlated with future HDP. However, predicting HDP during early pregnancy in women with a low fetal fraction might be difficult.

Aberrant histone modification in endometriosis.

Accumulating evidence suggests that epigenetic aberrations play definite roles in the pathogenesis of endometriosis. These include aberrations in genomic DNA methylation, microRNA expression, and histone modification. The aberrant histone modification status and the aberrant expression of histone deacetylases, which regulate histone acetylation, in endometriosis are the focus of this review. Herein, we summarize the recent studies in the following areas: (i) hyperacetylation of histones located in the promoter lesions of G-protein-coupled estrogen receptor 1, steroidogenic factor-1, and hypoxia-inducible factor-1 alpha genes and (ii) hypoacetylation of histones located in the promoter lesions of estrogen receptor alpha, homeobox A10, CCAAT/enhancer-binding protein alpha, p16(INK4a), p21(Waf1/Cip1), p27(Kip1), checkpoint kinase 2, death receptor 6, and E-cadherin genes. Further research from the viewpoint of epigenetics may lead to the identification of the candidate molecules that are aberrantly expressed in endometriosis and may help elucidate the pathogenesis of this disease. In addition, epigenetic drugs (including histone deacetylase inhibitors) show promise for the treatment of endometriosis by amending the expression of these epigenetically dysregulated genes.

CCAAT/enhancer-binding protein α is epigenetically silenced by histone deacetylation in endometriosis and promotes the pathogenesis of endometriosis.

CONTEXT: Accumulating evidence suggests that various epigenetic aberrations play definite roles in the pathogenesis of endometriosis. OBJECTIVE: The objective of the study was to determine the epigenetically silenced genes by histone deacetylation in endometriosis. DESIGN: Histone deacetylase-1 target mRNAs that were up-regulated by valproic acid (VPA) treatment in endometriotic cyst stromal cells (ECSCs) were identified by a global mRNA microarray technique. RESULTS: We identified 5 candidate genes and chose CCAAT/enhancer-binding protein α (C/EBPα) for further functional experiments. C/EBPα mRNA and protein expression is attenuated in ECSCs, and the expression was up-regulated by VPA stimulation. Immunohistochemical stainings also confirmed the decreased staining for C/EBPα protein in endometriotic tissues. VPA treatment resulted in an accumulation of acetylated histones H3 and H4 in the promoter region of the C/EBPα gene in ECSCs. The compulsory expression of C/EBPα in ECSCs directed the inhibition of cell proliferation and the induction of apoptosis. C/EBPα knockdown by small interfering RNA directed the stimulation of cell proliferation and the resistance to apoptosis in normal eutopic endometrial stromal cells. The expressions of peroxisome proliferator-activated receptor-γ (PPARγ), period homolog 2 (PER2), p53, apoptosis-inducing factor, mitochondrion-associated 1 (AIFM1), Bax, caspase-8, caspase-10, p16(INK4a), p21(Waf1/Cip1), cyclin-dependent kinase (cdk) 2, and cdk4 were down-regulated by C/EBPα knockdown. CONCLUSIONS: Our findings suggest that an epigenetically suppressed tumor suppressor gene is involved in the pathogenesis of endometriosis by creating the proliferative, antiapoptotic, and other disease-specific characteristics of endometriosis. The results also suggest that histone deacetylase inhibitors are promising agents for the treatment of endometriosis.

Death receptor 6 is epigenetically silenced by histone deacetylation in endometriosis and promotes the pathogenesis of endometriosis.

PROBLEM: The purpose of this study is to evaluate the involvement of death receptor (DR) 6 in the pathogenesis of endometriosis. METHODS OF STUDY: Endometriotic cyst stromal cells (ECSCs) and normal endometrial stromal cells (NESCs) were isolated from ovarian endometriotic tissues and the eutopic endometrial tissues, respectively. The effect of valproic acid (VPA) on the DR6 expression in ECSCs was examined. The roles of DR6 in NESC proliferation and apoptosis were investigated with DR6 siRNA transfection. The distribution of DR6 protein in ovarian endometriotic tissues and normal proliferative-phase endometrium was examined by immunohistochemistry. The expression of DR6 mRNA and protein in ECSCs and NESCs was also examined. RESULTS: Death receptor 6 expression was attenuated in ECSCs and in endometriotic tissues, and its expression was upregulated by VPA stimulation. VPA treatment resulted in an accumulation of acetylated histone H4 in the promoter region of the DR6 gene. DR6 knockdown directed the stimulation of cell proliferation and the resistance to apoptosis in NESCs. CONCLUSION: The present findings suggested that DR6 is involved in the pathogenesis of endometriosis by creating the proliferative and anti-apoptotic characteristics of endometriosis. The results also suggest that histone deacetylase inhibitors are promising agents for the treatment of endometriosis.