Beyond Immune Balance: The Pivotal Role of Decidual Regulatory T Cells in Unexplained Recurrent Spontaneous Abortion.

Recurrent spontaneous abortion (RSA) is defined as two or more consecutive pregnancy failures, which brings tremendous stress to women of childbearing age and seriously affects family well-being. However, the reason in about 50% of cases remains unknown and is defined as unexplained recurrent spontaneous abortion (URSA). The immunological perspective in URSA has attracted widespread attention in recent years. The embryo is regarded as a semi-allogeneic graft to the mother. A successful pregnancy requires transition to an immune environment conducive to embryo survival at the maternal-fetal interface. As an important member of regulatory immunity, regulatory T (Treg) cells play a key role in regulating immune tolerance at the maternal-fetal interface. This review will focus on the phenotypic plasticity and lineage stability of Treg cells to illustrate its relationship with URSA.

RANKL up-regulated by progesterone aggravates lipopolysaccharide-induced acute lung injury during pregnancy.

Acute lung injury (ALI) is a common acute respiratory disease with high morbidity and mortality rate in pregnant women. Receptor activator of NF-κB ligand (TNFSF11, also known as RANKL) exerts either pro-inflammatory or anti-inflammatory effects on the immune response. LPS administration reduced the survival time (n = 10, p < 0.01), increased wet/dry ratio (n = 10, p < 0.001) and lung injury score (n = 10, p < 0.001), the elevated proportions of plasmacytoid dendritic cells (pDCs) (n = 10, p < 0.0001), tissue-resident DCs (resDCs) (n = 10, p < 0.0001), macrophages (n = 10, p < 0.0001), and neutrophils (n = 10, p < 0.0001), and the expressions of costimulatory molecules and inflammation cytokines (n = 10, p < 0.05) in lungs of pregnant mice, compared with non-pregnant mice. In vitro, progesterone up-regulated the expression of RANKL (n > 6, p < 0.05) on pulmonary fibroblasts. The results of cytokine arrays showed that the cytokines associated with inflammatory response and leukocyte differentiation were decreased in pulmonary fibroblasts after treatment with anti-RANKL neutralizing antibody, compared with control pulmonary fibroblasts. More notably, we found that Tnfsf11-/- pregnant mice had longer survival durations (n = 10, p < 0.01), lower lung injury scores (n = 10, p < 0.05), and lower immune cell infiltration (n = 10, p < 0.05). These data imply that the RANKL/RANK axis plays an essential role in LPS-induced ALI during pregnancy possibly through a variety of pathways.

Decidual macrophages in recurrent spontaneous abortion.

Recurrent spontaneous abortion (RSA) is defined as two or more pregnancy loss, affecting the happiness index of fertility couples. The mechanisms involved in the occurrence of RSA are not clear to date. The primary problem for the maternal immune system is how to establish and maintain the immune tolerance to the semi-allogeneic fetuses. During the pregnancy, decidual macrophages mainly play an important role in the immunologic dialogue. The purpose of this study is to explore decidual macrophages, and to understand whether there is a connection between these cells and RSA by analyzing their phenotypes and functions. Pubmed, Web of Science and Embase were searched. The eligibility criterion for this review was evaluating the literature about the pregnancy and macrophages. Any disagreement between the authors was resolved upon discussion and if required by the judgment of the corresponding author. We summarized the latest views on the phenotype, function and dysfunction of decidual macrophages to illuminate its relationship with RSA.

Astrocyte-specific loss of lactoferrin influences neuronal structure and function by interfering with cholesterol synthesis.

Growing evidence indicates that circulating lactoferrin (Lf) is implicated in peripheral cholesterol metabolism disorders. It has emerged that the distribution of Lf changes in astrocytes of aging brains and those exhibiting neurodegeneration; however, its physiological and/or pathological role remains unknown. Here, we demonstrate that astrocyte-specific knockout of Lf (designated cKO) led to decreased body weight and cognitive abnormalities during early life in mice. Accordingly, there was a reduction in neuronal outgrowth and synaptic structure in cKO mice. Importantly, Lf deficiency in the primary astrocytes led to decreased sterol regulatory element binding protein 2 (Srebp2) activation and cholesterol production, and cholesterol content in cKO mice and/or in astrocytes was restored by exogenous Lf or a Srebp2 agonist. Moreover, neuronal dendritic complexity and total dendritic length were decreased after culture with the culture medium of the primary astrocytes derived from cKO mice and that this decrease was reversed after cholesterol supplementation. Alternatively, these alterations were associated with an activation of AMP-activated protein kinase (AMPK) and inhibition of SREBP2 nuclear translocation. These data suggest that astrocytic Lf might directly or indirectly control in situ cholesterol synthesis, which may be implicated in neurodevelopment and several neurological diseases.

Uterine natural killer cells and recurrent spontaneous abortion.

Recurrent spontaneous abortion (RSA), termed as two or more consecutive pregnancy loss is a great problem for some women of childbearing age. A large number of evidence confirm that there may be an immune background of RSA. As a member of the innate immune system, uterine natural killer (uNK) cells account for about 70% of total lymphocytes during pregnancy and play a critical role in the establishment and maintenance of pregnancy. This review mainly introduces the phenotype, origin, receptor, and function of uNK cells to illuminate its relationship with RSA.

Advances in the establishment and application of experimental models of optic neuritis associated with neuromyelitis optica / 国际眼科杂志(Guoji Yanke Zazhi)

@#Neuromyelitis optica(NMO)is an inflammatory central nervous system(CNS)astrocytic disease with high incidence, neuro-ophthalmic intercross, and humoral immune-dominated in Asian population. It has attracted much attention due to its high pathogenicity, high risk of recurrence, and poor prognosis. It is difficult for patients with NMO-associated optic neuritis(NMO-ON)to benefit from routine treatment, and they are often left with different degrees of optic nerve atrophy. One limitation of the study of NMO-ON is the deficiency of the experimental model. Therefore, the progress and application of NMO and NMO-ON experimental model are reviewed in this paper, aiming to explore the pathological mechanism and possible treatment of NMO visual impairment.

Recombinant human lactoferrin attenuates the progression of hepatosteatosis and hepatocellular death by regulating iron and lipid homeostasis in ob/ob mice.

Lactoferrin (Lf), an iron-binding glycoprotein, has been shown to possess antioxidant and anti-inflammatory properties and exert modulatory effects on lipid homeostasis and non-alcoholic fatty liver disease (NAFLD), but our understanding of its regulatory mechanisms is limited and inconsistent. We used leptin-deficient (ob/ob) mice as the rodent model of NAFLD, and administered recombinant human Lf (4 mg per kg body weight) or control vehicle by intraperitoneal injection to evaluate the hepatoprotective effects of Lf. After 40 days of treatment with Lf, insulin sensitivity and hepatic steatosis in ob/ob mice were significantly improved with the down-regulation of sterol regulatory element binding protein-2 (SREBP2), indicating an improvement in hepatic lipid metabolism and function. We further explored the mechanism, and found that Lf may increase the hepatocellular iron output by targeting the hepcidin-ferroportin (FPn) axis, and then maintains the liver oxidative balance through a nonenzymatic antioxidant system, ultimately suppressing the death of hepatocytes. In addition, the cytoprotective role of Lf may be associated with the inhibition of endoplasmic reticulum (ER) stress and inflammation, promotion of autophagy of damaged hepatocytes and induction of up-regulation of hypoxia inducible factor-1α/vascular endothelial growth factor (HIF-lα/VEGF) to facilitate liver function recovery. These findings suggest that recombinant human Lf might be a potential therapeutic agent for mitigating or delaying the pathological process of NAFLD.

ADATMS-7 regulates the focal adhesion kinase signaling and promotes invasiveness of trophoblasts in early pregnancy.

INTRODUCTION: ADAMTS-7, a member of the disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) family, was recently identified to be associated with cell migration and invasion. However, its function on trophoblasts remains unknown. In this study, we are aimed to investigate the role of ADAMTS-7 on trophoblasts in human first trimester gestation. METHODS: The expression of ADAMTS-7 in trophoblasts and HTR8/SVneo cells is examined by immunohistochemistry and quantitative real-time PCR. BrdU incorporation and Annexin V/PI staining are utilized to measure the effect of ADAMTS-7 on the proliferation and apoptosis of HTR8/SVneo cells, respectively. In addition, we detect the role of ADAMTS-7 on the invasion ability of HTR8/SVneo cells using matrigel invasion assays. The activation of focal adhesion kinase (FAK) and integrinß1 induced by ADAMTS-7 were determined by Western blot. RESULTS: ADAMTS-7 and its substrate cartilage oligomeric matrix protein (COMP) were expressed in both primary human trophoblasts and human trophoblast cell lines. TGF-ß1 induced a continuous and significant decrease of ADAMTS-7. Inversely, IL-1ß up-regulated the ADAMTS-7 level in a dosage dependent manner. In addition, knockdown of ADAMTS-7 inhibited the growth and invasion of HTR8/SVneo cells. To the contrary, ADAMTS-7 overexpression promoted the growth and invasion of HTR8/SVneo cells. ADAMTS-7 knockdown led to a decreased level of FAK Tyr-397 phosphorylation. DISCUSSION: Our results suggest that ADAMTS-7 may regulate trophoblasts invasion through focal adhesion kinase (FAK) signaling.

Decidual RANKL/RANK interaction promotes the residence and polarization of TGF-ß1-producing regulatory γδ T cells.

ABSTACT: Decidual Î³Î´Τ (dγδΤ) cells play an essential role during successful pregnancy; however, the residence and polarization of Î³Î´Τ cells in decidua remain unclear. In this study, we observed higher levels of receptor activator for nuclear factor-κ B ligand (RANKL) on decidual stromal cells (DSCs), and its receptor RANK on dÎ³Î´Τ cells in decidua from normal pregnancy compared with patients with recurrent spontaneous abortion (RSA). RANKL expressed by DSCs can induce the polarization of peripheral blood Î³Î´Τ (pγδΤ) and dÎ³Î´Τ cells to Foxp3 + Î³Î´Τ cells, and upregulate the expression of transforming growth factor (TGF)-ß1. This process is mediated through activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). In addition, RANKL promotes the adhesion of dÎ³Î´Τ cells to DSCs in vitro, which is associated with the upregulation of ICAM-1 and VCAM-1 on DSCs and integrins on dÎ³Î´Τ cells. RANKL knockout leads to the decreased numbers of uterus total Î³Î´Τ cells, Foxp3+Î³Î´Τ cells and the expression of TGF-ß1, and the increased pregnancy loss in mice. These results suggest that RANKL is a pivotal regulator of maternal-fetal tolerance by triggering the polarization and residence of TGF-ß1-producing Foxp3+Î³Î´Τ cells in early pregnancy. The abnormal low level of RANKL/RANK results in pregnancy loss because of the dialogue disorder between DSCs and dÎ³Î´Τ cells. This observation provides a scientific basis on which a potential marker can be detected to early warning of pregnancy loss.

Pleiotropic roles of melatonin in endometriosis, recurrent spontaneous abortion, and polycystic ovary syndrome.

Melatonin is a neurohormone synthesized from the aromatic amino acid tryptophan mainly by the pineal gland of mammals. Melatonin acts as a broad-spectrum antioxidant, powerful free radical scavenger, anti-inflammatory agent, anticarcinogenic factor, sleep inducer and regulator of the circadian rhythm, and potential immunoregulator. Melatonin and reproductive system are interrelated under both physiological and pathological conditions. Oxidative stress, inflammation, and immune dysregulation are associated with the pathogenesis of the female reproductive system which causes endometriosis (EMS), recurrent spontaneous abortion (RSA), and polycystic ovary syndrome (PCOS). Accumulating studies have indicated that melatonin plays pleiotropic and essential roles in these obstetrical and gynecological disorders and would be a candidate therapeutic drug to regulate inflammation and immune function and protect special cells or organs. Here, we systematically review the pleiotropic roles of melatonin in EMS, RSA, and PCOS to explore its pathological implications and treatment potential.

RANKL-mediated harmonious dialogue between fetus and mother guarantees smooth gestation by inducing decidual M2 macrophage polarization.

Decidual macrophages (dMϕ) contribute to maternal-fetal tolerance. However, the mechanism of dMϕ differentiation during pregnancy is still largely unknown. Here, we report that receptor activator for nuclear factor-κ B ligand (RANKL), secreted by human embryonic trophoblasts and maternal decidual stromal cells (DSCs), polarizes dMϕ toward a M2 phenotype. This polarization is mediated through activation of Akt/signal transducer and activator of transcription 6 (STAT6) signaling, which is associated with the upregulation of histone H3 lysine-27 demethylase Jmjd3 and IRF4 in dMϕ. Such differentiated dMϕ can induce a Th2 bias that promotes maternal-fetal tolerance. Impaired expression of RANKL leads to dysfunction of dMϕ in vivo and increased rates of fetal loss in mice. Transfer of RANK+Mϕ reverses mouse fetal loss induced by Mϕ depletion. Compared with normal pregnancy, there are abnormally low levels of RANKL/RANK in villi and decidua from miscarriage patients. These results suggest that RANKL is a pivotal regulator of maternal-fetal tolerance by licensing dMϕ to ensure a successful pregnancy outcome. This observation provides a scientific basis on which a potential therapeutic strategy can be targeted to prevent pregnancy loss.

Bone mesenchymal stem cells improve pregnancy outcome by inducing maternal tolerance to the allogeneic fetus in abortion-prone matings in mouse.

INTRODUCTION: The successful pregnancy depends on maternal immune tolerance against the fetus. It has been reported that MSCs (mesenchymal stem cells) could play a regulatory role on immune cells such as CD4+T cells, macrophages and NK cells, but their effect on recurrent miscarriage is unknown. STUDY DESIGN: In a prospective study, the abortion-prone (CBA/J × DBA/2) H-2d × H-2k mice were utilized. Female CBA/J mice (8-10 weeks old) were injected with vehicle or MSCs via tail vein or uterine horns, and 14 days later, they were mated with DBA/2 males for the following experiments. RESULTS: Comparing with the control group, the embryo resorption rate in MSCs-horn injection group was dramatically decreased. MSCs were mainly located at the maternal-fetal interface, indicating that the reduction of resorption rate was due to MSCs' local effect. No matter which treatment was given, there was no significant difference in the levels of IL-4, IL-10, TNF-α and IFN-γ in CD4+T cells and IL-10 and IL-12 in macrophages in spleens among each group. However, in contrast to other groups, the levels of IL-4 and IL-10 in CD4+T cells localized at the maternal-fetal interface in MSCs-horn injection group were dramatically increased, and TNF-α and IFN-γ levels were notably decreased. While IL-10 expressed in macrophages was obviously higher than other groups and IL-12 in macrophages was significantly lower than other groups. CONCLUSIONS: The findings indicate that MSCs injection through uterine horns could decrease embryo resorption rate.

Chemokine CCL17 induced by hypoxia promotes the proliferation of cervical cancer cell.

Cervical cancer is often associated with hypoxia and many kinds of chemokines. But the relationship and role of hypoxia and Chemokine (C-C motif) ligand 17 (CCL17) in cervical cancer are still unknown. Here, we found that CCL17 was high expressed in cervical cancer. HeLa and SiHa cells could secrete CCL17 in a time-dependent manner. Hypoxia increased expression of CCL17 receptor (CCR4) on HeLa and SiHa cells. Treatment with recombination human CCL17 (rhCCL17) led to an elevation of cell proliferation in HeLa and SiHa cells in a dose-dependent manner. In contrast, blocking CCL17 with anti-human CCL17 neutralizing antibody (α-CCL17) played an oppose effect. However, rhCCL17 had no effect on apoptosis in cervical cancer cells. Further analysis showed that hypoxia promoted the proliferation of HeLa and SiHa cells, and these effects could be reversed by α-CCL17. Stimulation with the inhibitor for c-Jun N-terminal kinase (JNK) or signal transducers and activator of transcription 5 (STAT5) signal pathway not only directly decreased the proliferation of HeLa and SiHa cells, but also abrogated the stimulatory effect of rhCCL17 on the proliferation of HeLa and SiHa cells. These results suggest that a high level of CCL17 in cervical cancer lesions is an important regulator in the proliferation of cervical cancer cells through JNK and STAT5 signaling pathways. In this process, hypoxia magnifies this effect by up-regulating CCR4 expression and strengthening the interaction of CCL17/CCR4.

Chemokine CCL24 promotes the growth and invasiveness of trophoblasts through ERK1/2 and PI3K signaling pathways in human early pregnancy.

Chemokine CCL24, acting through receptor CCR3, is a potent chemoattractant for eosinophil in allergic diseases and parasitic infections. We recently reported that CCL24 and CCR3 are co-expressed by trophoblasts in human early pregnant uterus. Here we prove with evidence that steroid hormones estradiol (E), progesterone (P), and human chorionic gonadotropin (hCG), as well as decidual stromal cells (DSCs) could regulate the expression of CCL24 and CCR3 of trophoblasts. We further investigate how trophoblast-derived CCL24 mediates the function of trophoblasts in vitro, and conclude that CCL24/CCR3 promotes the proliferation, viability and invasiveness of trophoblasts. In addition, analysis of the downstream signaling pathways of CCL24/CCR3 show that extracellular signal-regulated kinases (ERK1/2) and phosphoinositide 3-kinase (PI3K) pathways may contribute to the proliferation, viability and invasiveness of trophoblasts by activating intracellular molecules Ki67 and matrix metallopeptidase 9 (MMP9). However, we did not observe any inhibitory effect on trophoblasts when blocking c-Jun N-terminal kinase (JNK) or p38 pathways. In conclusion, our data suggests that trophoblast-derived CCL24 at the maternal-fetal interface promotes trophoblasts cell growth and invasiveness by ERK1/2 and PI3K pathways. Meanwhile, pregnancy-related hormones (P and hCG), as well as DSCs could up-regulate CCL24/CCR3 expression in trophoblasts, which may indirectly influence the biological functions of trophoblasts. Thus, our results provide a possible explanation for the growth and invasion of trophoblasts in human embryo implantation.

The infiltration and functional regulation of eosinophils induced by TSLP promote the proliferation of cervical cancer cell.

Cervical cancer is often associated with eosinophil (EOS) infiltration, but the source and the role of EOS are still largely unknown. Our previous work has established that thymic stromal lymphopoietin (TSLP) can stimulate the growth of cervical cancer cell in an autocrine manner. Here, we report that EOS infiltration of the lesion site increased gradually with the progression of cervical cancer. The increase in TSLP secretion in HeLa and SiHa cells induced by hypoxia led to a high level of chemokine CCL17 production by HeLa and SiHa cells, and recruited more EOS to the cancer lesion. In addition, TSLP derived from HeLa and SiHa cells promoted proliferation, up-regulated the levels of anti-inflammatory cytokines (IL-10, IL-4, IL-5 and IL-13), and decreased the expression of CD80 and CD86 of EOS. Such educated EOS significantly promoted proliferation and restricted the apoptosis of cervical cancer cells, which was associated with the up-regulation of Ki-67, PCNA and Bcl-2, and the down-regulation of Fas and FasL in HeLa and SiHa cells. These results suggest that a high level of TSLP in cancer lesions mediated by hypoxia is an important regulator of the progression of cervical cancer by recruiting and licensing tumor-associated EOS to promote the growth of the cervical cancer cell itself. This provides a scientific basis on which potential therapeutic strategies could be targeted to cervical cancer, especially for patients with massive infiltrations of EOS.

FOXL2 suppresses proliferation, invasion and promotes apoptosis of cervical cancer cells.

FOXL2 is a transcription factor that is essential for ovarian function and maintenance, the germline mutations of which give rise to the blepharophimosis ptosis epicanthus inversus syndrome (BPES), often associated with premature ovarian failure. Recently, its mutations have been found in ovarian granulosa cell tumors (OGCTs). In this study, we measured the expression of FOXL2 in cervical cancer by immunohistochemistry and its mRNA level in cervical cancer cell lines Hela and Siha by RT-PCR. Then we overexpressed FOXL2 in Hela cells and silenced it in Siha cells by plasmid transfection and verified using western blotting. When FOXL2 was overexpressed or silenced, cells proliferation and apoptosis were determined by Brdu assay and Annexin V/PI detection kit, respectively. In addition, we investigated the effects of FOXL2 on the adhesion and invasion of Hela and Siha cells. Finally, we analyzed the influences of FOXL2 on Ki67, PCNA and FasL by flow cytometry. The results showed that FOXL2 was highly expressed in cervical squamous cancer. Overexpressing FOXL2 suppressed Hela proliferation and facilitated its apoptosis. Silencing FOXL2 enhanced Siha proliferation and inhibited its apoptosis. Meanwhile, silencing FOXL2 promoted Siha invasion, but it had no effect on cells adhesion. In addition, overexpressing FOXL2 decreased the expression of Ki67 in Hela and Siha cells. Therefore, our results suggested that FOXL2 restrained cells proliferation and enhanced cells apoptosis mainly through decreasing Ki67 expression.

Hypoxia promotes the proliferation of cervical carcinoma cells through stimulating the secretion of IL-8.

To explore whether hypoxia and interleukin 8 (IL-8) regulate the viability and apoptosis of cervical carcinomas cells and the possible mechanism. We evaluated the expression of hypoxia inducible factor-1α (HIF-1α), IL-8 and its receptors (CXCR1 and CXCR2) in cervical cancer and cervicitis tissues by immunohistochemistry. Then the effects of hypoxia and IL-8 on the viability and apoptosis of HeLa and SiHa cells were detected by the SRB and apoptosis assays. Here we observed that the expression of HIF-1α, IL-8 and CXCR1 in cervical cancer tissues was significantly higher than that in cervicitis tissues. Hypoxic condition stimulated the secretion of IL-8 and the expression of CXCR1 and CXCR2 on HeLa and SiHa cells. Recombinant human IL-8 enhanced the viability and reduced the apoptosis in HeLa and SiHa cells. HeLa and SiHa cells cultured in 1% oxygen showed the increased viability and apoptosis, and the former effect could be partly reversed by anti-human IL-8 neutralizing antibody. This data suggested that IL-8 secreted by cervical carcinomas cells induced by hypoxia can stimulate the viability of cervical carcinomas cells in an autocrine dependent manner, and contribute to the pathogenesis of cervical cancer.

NME1 suppression of endometrial stromal cells promotes angiogenesis in the endometriotic milieu via stimulating the secretion of IL-8 and VEGF.

Nonmetastatic gene 23-H1 (NME1, also known as nm23-H1) is a wide-spectrum tumor metastasis suppressor gene that plays an important role in suppressing the proliferation, adhesion and invasion of endometrial stromal cells (ESCs). The present study is undertaken to explore the mechanism by which NME1 in ESCs from endometriosis modulates the angiogenesis and herein participates in the pathogenesis of endometriosis. The expression of NME1 in the primary ESCs from normal endometrium without endometriosis was higher than that from eutopic endometrium and ectopic lesion with endometriosis. Silencing NME1 stimulated the secretion of angiogenic factors interleukin-8 (IL-8) and vascular-endothelial growth factor (VEGF) of the eutopic ESCs from women with endometriosis, and these effects could be abrogated by MAPK/ERK1/2 or AKT inhibitor. In addition, the supernatant of NME1-silenced ESCs increased the expression of angiogenesis-relative molecules CD62E and CD105, and promoted angiogenesis of human umbilical vein endothelial cells (HUVECs). Anti-human IL-8 or VEGF neutralizing antibody reversed the effect on angiogenesis of HUVECs induced by NME1-silenced ESCs. Our current results suggest that the abnormal lower expression of NME1 in ESCs secrete more IL-8 and VEGF through activation of MAPK/ERK1/2 and AKT signal pathways, up-regulate the level of CD62E and CD105, and finally lead to numerous angiogenesis of vascular endothelial cells in the endometriotic milieu, which is beneficial to the origin and development of endometriosis.

NME1 suppression promotes growth, adhesion and implantation of endometrial stromal cells via Akt and MAPK/Erk1/2 signal pathways in the endometriotic milieu.

STUDY QUESTION: Is Nometastatic gene 23-H1 (NME1, also known as nm23-H1) involved in regulating the biological behavior of endometrial stromal cells (ESCs), and does it participate in the pathogenesis of endometriosis? SUMMARY ANSWER: NME1 suppression induces ESC dysfunction in the endometriotic milieu. WHAT IS KNOWN ALREADY: NME1 is a wide-spectrum tumor metastasis suppressor gene that plays an important role in suppressing the invasion and metastasis of tumor cells. STUDY DESIGN, SIZE, DURATION: An in vitro investigation of the effect of NME1 on the proliferation, adhesion and invasion of eutopic ESCs from patients with endometriosis. PARTICIPANTS/MATERIALS, SETTING, METHODS: Primary ESCs were prepared from 12 samples of ectopic endometrial tissue (6 peritoneal and 6 ovarian lesions), 18 samples of eutopic endometrial tissues (16 from women with ovarian and 2 from women with pelvic endometriomas) and 12 samples of normal endometrial tissue from women without endometriosis, after the tissues had been analyzed histologically. The growth, invasiveness and adhesion of ESCs were studied by the 5-bromo-2'-deoxyuridine cell proliferation assay and by the Matrigel invasion and adhesion assay. Additionally, the effects of NME1 on the activation or expression of related regulatory proteins were investigated by in-cell Western and flow cytometry assays. MAIN RESULTS AND THE ROLE OF CHANCE: Expression of NME1 in ESCs derived from eutopic or ectopic endometrium from women with endometriosis is lower than in ESCs from women without endometriosis. Estrogen could down-regulate NME1 expression in ESCs. Silencing NME1 in ESCs promoted the expression of proliferating cell nuclear antigen (PCNA), the anti-apoptotic molecule, survivin, and the adhesion-related molecules, integrin ß1 and integrin ανß3. Silencing NME1 also stimulated ESC proliferation, adhesion and invasion but these effects were inhibited by MAPK/Erk and/or Akt blockers. LIMITATIONS, REASONS FOR CAUTION: Further studies are needed to examine the regulatory mechanism of estrogen on NME1 expression of ESCs. WIDER IMPLICATIONS OF THE FINDINGS: Abnormally low expression of NME1 in ESCs may be involved in the pathogenesis of endometriosis by up-regulating growth, adhesion and invasion of ESCs via activating the Akt and MAPK/Erk1/2 signal pathways. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by National Natural Science Foundation of China (NSFC) (31270969, 31101064 and 81270677) and Program for ZhouXue of Fudan University. None of the authors has any conflict of interest to declare.