Up-regulation of Bcl-2 by CD147 Through ERK Activation Results in Abnormal Cell Survival in Human Endometriosis

Molecular Mechanisms of Endometriosis Revealed Using Omics Data

Endometriosis is a gynecological disorder prevalent in women of reproductive age. The primary symptoms include dysmenorrhea, irregular menstruation, and infertility. However, the pathogenesis of endometriosis remains unclear. With the advent of high-throughput technologies, various omics experiments have been conducted to identify genes related to the pathophysiology of endometriosis. This review highlights the molecular mechanisms underlying endometriosis using omics. When genes identified in omics experiments were compared with endometriosis disease genes identified in independent studies, the number of overlapping genes was moderate. However, the characteristics of these genes were found to be equivalent when functional gene set enrichment analysis was performed using gene ontology and biological pathway information. These findings indicate that omics technology provides invaluable information regarding the pathophysiology of endometriosis. Moreover, the functional characteristics revealed using enrichment analysis provide important clues for discovering endometriosis disease genes in future research.

Altered Differential Expression of Genes and microRNAs Related to Adhesion and Apoptosis Pathways in Patients with Different Phenotypes of Endometriosis

We aim to investigate the expression of genes (MAPK1 and CAPN2) and microRNAs (miR-30a-5p, miR-7-5p, miR-143-3p, and miR-93-5p) involved in adhesion and apoptosis pathways in superficial peritoneal endometriosis (SE), deep infiltrating endometriosis (DE), and ovarian endometrioma (OE), and to evaluate whether these lesions share the same pathophysiological mechanisms. We used samples of SE (n = 10), DE (n = 10), and OE (n = 10), and endometrial biopsies of these respective patients affected with endometriosis under treatment at a tertiary University Hospital. Endometrial biopsies collected in the tubal ligation procedure from women without endometriosis comprised the control group (n = 10). Quantitative real-time polymerase chain reaction was performed. The expression of MAPK1 (p < 0.0001), miR-93-5p (p = 0.0168), and miR-7-5p (p = 0.0006) was significantly lower in the SE group than in the DE and OE groups. The expression of miR-30a (p = 0.0018) and miR-93 (p = 0.0052) was significantly upregulated in the eutopic endometrium of women with endometriosis compared to the controls. MiR-143 (p = 0.0225) expression also showed a statistical difference between the eutopic endometrium of women with endometriosis and the control group. In summary, SE showed lower pro-survival gene expression and miRNAs involved in this pathway, indicating that this phenotype has a different pathophysiological mechanism compared to DE and OE.

CD147 and MMPs as key factors in physiological and pathological processes

Cluster of differentiation 147 (CD147) or extracellular matrix metalloproteinase inducer (EMMPRIN) is a transmembrane glycoprotein that induces the synthesis of matrix metalloproteinases (MMPs). MMPs, as zinc-dependent proteases and versatile enzymes, play critical roles in the degradation of the extracellular matrix (ECM) components, cleaving of the receptors of cellular surfaces, signaling molecules, and other precursor proteins, which may lead to attenuation or activation of such targets. CD147 and MMPs play essential roles in physiological and pathological conditions and any disorder in the expression, synthesis, or function of CD147 and MMPs may be associated with various types of disease. In this review, we have focused on the roles of CD147 and MMPs in some major physiological and pathological processes.

A molecular atlas of the human postmenopausal fallopian tube and ovary from single-cell RNA and ATAC sequencing

As part of the Human Cell Atlas Initiative, our goal is to generate single-cell transcriptomics (single-cell RNA sequencing [scRNA-seq], 86,708 cells) and regulatory (single-cell assay on transposase accessible chromatin sequencing [scATAC-seq], 59,830 cells) profiles of the normal postmenopausal ovary and fallopian tube (FT). The FT contains 11 major cell types, and the ovary contains 6. The dominating cell type in the FT and ovary is the stromal cell, which expresses aging-associated genes. FT epithelial cells express multiple ovarian cancer risk-associated genes (CCDC170, RND3, TACC2, STK33, and ADGB) and show active communication between fimbrial epithelial cells and ovarian stromal cells. Integrated single-cell transcriptomics and chromatin accessibility data show that the regulatory landscape of the fimbriae is different from other anatomic regions. Cell types with similar gene expression in the FT display transcriptional profiles. These findings allow us to disentangle the cellular makeup of the postmenopausal FT and ovary, advancing our knowledge of gynecologic diseases in menopause.

Regulatory Role of Apoptotic and Inflammasome Related Proteins and Their Possible Functional Aspect in Thiram Associated Tibial Dyschondroplasia of Poultry

Tibial dyschondroplasia debilities apoptotic and inflammasomal conditions that can further destroy chondrocytes. Inflammasomes are specialized protein complexes that process pro-inflammatory cytokines, e.g., interleukin-1β (IL-1β) and IL-18. Moreover, there is mounting evidence that many of the signaling molecules that govern programmed cell death also affect inflammasome activation in a cell-intrinsic way. During the last decade, apoptotic functions have been described for signaling molecules involving inflammatory responses and cell death pathways. Considering these exceptional developments in the knowledge of processes, this review gives a glimpse of the significance of these two pathways and their connected proteins in tibial dyschondroplasia. The current review deeply elaborates on the elevated level of signaling mediators of mitochondrial-mediated apoptosis and the inflammasome. Although investigating these pathways’ mechanisms has made significant progress, this review identifies areas where more study is especially required. It might lead to developing innovative therapeutics for tibial dyschondroplasia and other associated bone disorders, e.g., osteoporosis and osteoarthritis, where apoptosis and inflammasome are the significant pathways.

Virus-Mediated Inhibition of Apoptosis in the Context of EBV-Associated Diseases: Molecular Mechanisms and Therapeutic Perspectives

Epstein-Barr virus (EBV), the representative of the Herpesviridae family, is a pathogen extensively distributed in the human population. One of its most characteristic features is the capability to establish latent infection in the host. The infected cells serve as a sanctuary for the dormant virus, and therefore their desensitization to apoptotic stimuli is part of the viral strategy for long-term survival. For this reason, EBV encodes a set of anti-apoptotic products. They may increase the viability of infected cells and enhance their resistance to chemotherapy, thereby contributing to the development of EBV-associated diseases, including Burkitt’s lymphoma (BL), Hodgkin’s lymphoma (HL), gastric cancer (GC), nasopharyngeal carcinoma (NPC) and several other malignancies. In this paper, we have described the molecular mechanism of anti-apoptotic actions of a set of EBV proteins. Moreover, we have reviewed the pro-survival role of non-coding viral transcripts: EBV-encoded small RNAs (EBERs) and microRNAs (miRNAs), in EBV-carrying malignant cells. The influence of EBV on the expression, activity and/or intracellular distribution of B-cell lymphoma 2 (Bcl-2) protein family members, has been presented. Finally, we have also discussed therapeutic perspectives of targeting viral anti-apoptotic products or their molecular partners.

The expression of BECN1, LC3B, and BCL2 genes in eutopic endometrium of patients with adenomyosis: A cross-sectional study

Introduction:

Both autophagy and apoptosis play a role in the cyclic remodeling of the endometrium. The abnormal regulation of genes and signaling pathways in the eutopic endometrium plays a role in the abnormal migration and implantation in adenomyosis.

Objective:

The present study investigates the mRNA expression of autophagy and apoptosis-related genes BECN1, LC3B, and BCL2 in the eutopic endometrium of patients with adenomyosis compared with healthy premenopausal women.

Materials and methods:

The present work was a cross-sectional study conducted between July 2018 and April 2019. The participants were 32 premenopausal women who attended the surgery for adenomyosis and other benign gynecological conditions. The participants were divided into two groups, with 16 women in the adenomyosis group and 16 healthy women in the control group. Endometrial tissues were collected during the proliferative menstrual phase for a quantitative real-time polymerase chain reaction.

Results:

The mRNA expression of BECN1, LC3B, and BCL2 were normalized by geometric mean mRNA expression of actin and GAPDH. There was no significant difference in mRNA expression for all three genes when comparing the control and adenomyosis groups.

Conclusions:

The mRNA expressions of autophagy-related genes BECN1 and LC3B and anti-apoptosis-related gene BCL2 were not significantly different in the eutopic endometrium of patients with adenomyosis compared with healthy premenopausal women during the proliferative menstrual phase.

Lipidomic Alterations and PPARα Activation Induced by Resveratrol Lead to Reduction in Lesion Size in Endometriosis Models

Endometriosis is an estrogen-dependent chronic inflammatory disease that affects approximately 10% of women of reproductive age and up to 50% of women with infertility. The heterogeneity of the disease makes accurate diagnosis and treatment a clinical challenge. In this study, we generated two models of endometriosis: the first in rats and the second using human ectopic endometrial stromal cells (HEcESCs) derived from the lesion tissues of endometriosis patients. We then applied resveratrol to assess its therapeutic potential. Resveratrol intervention had significant efficacy to attenuate lesion size and to rectify aberrant lipid profiles of model rats. Lipidomic analysis revealed significant lipidomic alterations, including notable increases of sphingolipids and decreases of both glycerolipids and most phospholipids. Upon resveratrol application, both proliferation capacity and invasiveness parameters decreased, and the early apoptosis proportion increased for HEcESCs. The activation of PPARα was also noted as a factor potentially contributing to recovery from endometriosis in both models. Our study provides valuable insight into the mechanisms of resveratrol in endometriosis and therefore strengthens the potential for optimizing resveratrol treatment for this disease.

MicroRNA miR-106a-5p targets forkhead box transcription factor FOXC1 to suppress the cell proliferation, migration, and invasion of ectopic endometrial stromal cells via the PI3K/Akt/mTOR signaling pathway

Emerging evidence has exhibited an obvious decreased expression of miR-106a-5p in the ectopic endometrial tissue of endometriosis (EMS) patients. Thus far, the pathophysiological function of miR-106a-5p in EMS is unknown. A previous study showed an increased FOXC1 expression in the ectopic endometrial tissue of patients with EMS. Moreover, we found that there was a binding site of miR-106a-5p on the 3'UTR of FOXC1 through bioinformatics predictions. Hence, we speculated that miR-106a-5p might affect the development of EMS via targeting FOXC1. We first showed a decreased level of miR-106a-5p and an increased level of FOXC1 mRNA in ectopic endometrial tissues compared with normal tissues. Functionally, we transfected ectopic endometrial stromal cells (ESCs) with miR-106a-5p mimics or NC mimics and indicated an inhibitory role of miR-106a-5p on ESC proliferation, invasion, and migration. Mechanistically, FOXC1 was found to be a target gene of miR-106a-5p. To confirm whether miR-106a-5p exerted an inhibitory activity in ESCs via targeting FOXC1, miR-106a-5p mimic was co-transfected into ESCs with the FOXC1-plasmid or vector. We found that FOXC1 overexpression evidently reversed the results caused by a miR-106a-5p mimic in ESCs. Additionally, our results demonstrated that miR-106a-5p mimic inhibited the expression of p-Akt and p-PI3K. Collectively, these results revealed that miR-106a-5p inhibited the proliferative, migratory, and invasive ability of ESCs via directly binding to FOXC1, likely through the suppression of the PI3K and its downstream signaling pathway, which offered a potential and novel therapeutic strategy for EMS treatment.

Cluster of differentiation 147 (CD147) expression is linked with thiram induced chondrocyte's apoptosis via Bcl-2/Bax/Caspase-3 signalling in tibial growth plate under chlorogenic acid repercussion

Tibial dyschondroplasia (TD) is a metabolic disease of young poultry that affects bone andcartilage's growth. It mostly occurs in broilers due to thiram toxicity in the feed. In this disease, tibial cartilage is not yet ripe for ossification, but it also results in lameness, death, and moral convictions of commercial poultry due to numerous apoptotic changes on cell level. These changes serve a cardinal role in this situation. Many potential problems indicate that chlorogenic acid (CGA) performs an extensive role in controlling apoptosis's perception. However, the actual role of CGA in TD affected chondrocytes in-vitro is still unidentified. The current study investigates the imperceptible insight of CGA on chondrocyte's apoptosis via B-cell lymphoma 2 (Bcl-2), Bcl-2 associated x-protein (Bax), and Caspase-3 with CD147 signalling. The expression of these markers was investigated by Immunofluorescence, western blot analysis, and reverse transcription-quantitative polymerase chain (RT-qPCR). Chondrocytes from the growth plate of tibia were isolated, cultured, and processed. A sub-lethal thiram (2.5 μg/mL) was used to induce cytotoxicity and then treated with an optimum dose (40 μg/ mL) of CGA. According to the results, thiram distorted chondrocyte cells with enhanced apoptotic rate. But, in case of CGA, high expression of CD147 enhanced cell viability of chondrocytes, accompanied by downregulation of Bax/Caspase-3 signalling with the upregulation of Bcl-2. The first possibility has ruled out in the present study by the observation that the cells apoptosis marker, Caspase-3 showed a significant change in CD147 overexpressing cells. Conversely, immunodepletion of CD147 with enhanced cleavage of Caspase-3, indicating the activation of apoptosis in chondrocytes cells. Therefore, these findings suggest a novel insight about CD147 in thiram induced TD about the regulation of Bcl-2/Bax/Caspase-3 apoptosis-signalling axis.

The role of mitogen-activated protein kinase signaling pathway in endometriosis

AIM

Endometriosis is an estrogen-dependent chronic inflammatory condition which causes pain, infertility, and predisposition for ovarian cancer. Endometriosis generates a unique microenvironment for survivability of endometriotic lesions which includes cell proliferation, differentiation, migration, and apoptosis. For these cellular activities, cascading activations of intracellular kinases are needed. Many kinase signaling pathways, IKKβ/NK-κB pathway, PI3K/AKT/mTOR, and the mitogen-activated protein kinase (MAPK) pathways (ERK1/2, p38, and JNK), are activated in endometriosis. In this review, we focus on the role of MAPK pathways in endometriosis.

METHODS

To identify the role of MAP Kinase signaling pathway in endometriosis we searched the Pubmed database using the search terms in various combinations "endometriosis," "endometrium," "ovary," "MAPK pathway," "ERK pathway," "p38 pathway," "JNK pathway," "estrogen," and "progesterone."

RESULTS

According to the current literature, MAPK signaling pathway has various roles in generating microenvironment and survival of endometriosis. Abnormal MAPK activation in migration, implantation, growth, invasion into the pelvic structures, proliferation, and apoptosis leads to the form of endometriosis and to worsen the condition in patients with endometriosis.

CONCLUSION

To further investigations on the effective and long-term endometriosis treatment, MAPK signaling pathways may be targeted. Molecular mechanism of MAPK signaling pathway in endometriosis should be more deeply understood and clinical trials should be more commonly performed for possible new endometriosis treatments to improve fertility and rescue endometriosis irreversibly.

Endometriosis Cell Proliferation Induced by Bone Marrow Mesenchymal Stem Cells

Endometriosis is an estrogen-dependent gynecological disorder that affects 10% of reproductive-aged women and causes pelvic pain and infertility. Bone marrow-derived stem cells (BMDCs) are known to engraft endometriosis in association with lesion growth; however, they do not undergo significant clonal expansion. The indirect effects of BMDCs on endometriosis growth and cell proliferation are not well characterized. Here, we demonstrate that BMDCs' co-culture increased endometrial stromal cell proliferation. In vitro studies using endometrial cells showed that BMDCs increased cell proliferation and activation of CDK1 in both an endometriosis cell line and primary endometrial stromal cells from women with endometriosis, however not in normal endometrial cells. In vivo studies using a mouse model of endometriosis showed increased CDK1+ expression associated with engrafted GFP + BMDCs. These results suggest that endometrial cell proliferation is induced by stem cell-derived trophic factors leading to the growth of endometriotic lesions. Targeting the specific signaling molecules secreted by BMDC may lead to novel therapeutic strategies for controlling cell proliferation in endometriosis.

An Addition of U0126 Protecting Heart Grafts From Prolonged Cold Ischemia-Reperfusion Injury in Heart Transplantation: A New Preservation Strategy

BACKGROUND

Ischemia-reperfusion injury (IRI) is the major cause of primary graft dysfunction in organ transplantation. The mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) signaling pathway plays a crucial role in cell physiological and pathological processes including IRI. This study aims to investigate whether inhibition of ERK signaling with U0126 can prevent prolonged cold IRI in heart transplantation.

METHODS

Rat cardiac cell line H9c2 cells were treated with U0126 before exposure to hypothermic hypoxia/reoxygenation (H/R) conditions. The effect of U0126 on H9c2 cells in response to H/R stress was determined by measuring cell death, reactive oxygen species production, mitochondrial membrane potential, and ERK signaling activation. Mouse syngeneic heterotopic heart transplantation was conducted, where a donor heart was preserved in the University of Wisconsin (UW) solution supplemented with U0126 for 24 hours at 4°C before transplantation. Heart graft function, histopathologic changes, apoptosis, and fibrosis were measured to assess IRI.

RESULTS

Phosphorylated ERK was increased in both in vitro H/R-injured H9c2 cells and in vivo heart grafts with IRI. Pretreatment with U0126 inhibited ERK phosphorylation and prevented H9c2 cells from cell death, reactive oxygen species generation, and mitochondrial membrane potential loss in response to H/R. Preservation of donor hearts with U0126-supplemented solution improved graft function and reduced IRI by reductions in cell apoptosis/death, neutrophil infiltration, and fibrosis of the graft.

CONCLUSIONS

Addition of U0126 to UW solution reduces ERK signal activation and attenuates prolonged cold IRI in a heart transplantation model. ERK inhibition with U0126 may be a useful strategy to minimize IRI in organ transplantation.

Lipidomic Alterations and PPARα Activation Induced by Resveratrol Lead to Reduction in Lesion Size in Endometriosis Models

Endometriosis is an estrogen‐dependent chronic inflammatory disease that affects approximately 10% of women of reproductive age and up to 50% of women with infertility. The heterogeneity of the disease makes accurate diagnosis and treatment a clinical challenge. In this study, we generated two models of endometriosis: the first in rats and the second using human ectopic endometrial stromal cells (HEcESCs) derived from the lesion tissues of endometriosis patients. We then applied resveratrol to assess its therapeutic potential. Resveratrol intervention had significant efficacy to attenuate lesion size and to rectify aberrant lipid profiles of model rats. Lipidomic analysis revealed significant lipidomic alterations, including notable increases of sphingolipids and decreases of both glycerolipids and most phospholipids. Upon resveratrol application, both proliferation capacity and invasiveness parameters decreased, and the early apoptosis proportion increased for HEcESCs. The activation of PPARα was also noted as a factor potentially contributing to recovery from endometriosis in both models. Our study provides valuable insight into the mechanisms of resveratrol in endometriosis and therefore strengthens the potential for optimizing resveratrol treatment for this disease.

Hypomethylation of the GSTM1 promoter is associated with ovarian endometriosis

STUDY QUESTION

Is the methylation status of the glutathione S-transferase M1 (GSTM1) promoter region altered in patients with ovarian endometriosis, and does this affect the expression of GSTM1 in their endometrial tissues?

SUMMARY ANSWER

The promoter region of GSTM1 was significantly hypomethylated in the ectopic and eutopic endometrium of patients with ovarian endometriosis and this was associated with higher expression of GSTM1 mRNA.

WHAT IS KNOWN ALREADY

GSTM1, a member of the glutathione S-transferase family, is primarily known as a detoxification enzyme, but it has also been shown to negatively regulate apoptosis-related signalling cascades through protein-protein interactions with apoptosis signal-regulating kinase-1.

STUDY DESIGN, SIZE, DURATION

This is a case-control study between September 2013 and December 2016, involving 65 patients with ovarian endometriosis and 53 women without endometriosis. We analysed the methylation status and expression levels of GSTM1 in the ectopic and eutopic endometrium of patients with ovarian endometriosis and the endometrium of women without endometriosis. In addition, we collected endometrial samples from 12 women without endometriosis for endometrial epithelial cell cultures.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Methylation levels of the GSTM1 promoter region in the ectopic and eutopic endometrial tissues of patients with ovarian endometriosis and the endometrial tissues of women without endometriosis were analysed by pyrosequencing. The expression of GSTM1 mRNA and protein in endometrial tissues was investigated by RT-qPCR and immunohistochemistry, respectively. Primary cell culture, gene transfection, Cell Counting Kit-8 assay and flow cytometry were used to analyse the effect of GSTM1 on viability and apoptosis in endometrial epithelial cells.

MAIN RESULTS AND THE ROLE OF CHANCE

Compared with that in the endometrium of women without endometriosis, the GSTM1 promoter region was significantly hypomethylated in the ectopic and eutopic endometrium of patients with ovarian endometriosis. Additionally, GSTM1 mRNA and protein levels were significantly higher in the ectopic and eutopic endometrium than in the control endometrium. Moreover, the methylation levels of the GSTM1 promoter region were significantly negatively correlated with the mRNA expression of GSTM1. Furthermore, in vitro results suggested that the over-expression of GSTM1 could significantly increase viability and inhibit apoptosis in endometrial epithelial cells following hormone treatment and withdrawal.

LIMITATIONS, REASONS FOR CAUTION

Due to restrictions in the isolation and culture of pure populations of endometrial epithelial cells, as well as limitations in the number of passages possible in primary cells, we could not explore the underlying molecular mechanism by which GSTM1 modulates apoptosis in endometrial cells.

WIDER IMPLICATIONS OF THE FINDINGS

This study provides new evidence to support the notion that endometriosis may be an epigenetic disease.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by grants from the Natural Science Foundation of Hebei Province (Grant number: H2018206200) and the Department of Education of Hebei Province (Grant number: CXZZBS2017114). The authors have no conflicts of interest to declare.

The role of extracellular matrix metalloproteinase inducer on the action of dihydrotestosterone against the cellular damage induced by Aβ42

Clinical studies have revealed that the risk of Alzheimer's disease (AD) in men is increased by age-related androgen depletion. The level of β-amyloid (Aβ) is elevated in the brains of AD patients, and Aβ is believed to play a critical role in the pathology of AD. Some studies have indicated that androgens affect AD risk by regulating the metabolism of Aβ by an unclear mechanism. In this study, we investigated the role of the extracellular matrix metalloproteinase inducer (CD147) in this action. Initially, we demonstrated that androgens positively regulate the expression of CD147 in adult male rats and SH-SY5Y cells. Furthermore, this regulation may involve androgen receptor (AR). Additionally, interference of CD147 expression decreased the clearance of Aβ in culture medium and reduced cell viability. It also affected the morphology of the cells and the expression of apoptosis-related proteins. Finally, we found that interference of CD147 expression blocked the dihydrotestosterone (DHT)-induced reduction in Aβ and the protection of cells. DHT regulates MMP-2's expression through CD147. Together, these results imply that androgen regulation of Aβ and cell protection may be affected by interfering with the expression of CD147.

Identification of a Bcl-xL homolog from orange-spotted grouper (Epinephelus coioides) involved in SGIV-induced nonapoptotic cell death

Bcl-2 family proteins play essential roles in modulating immune response and controlling cells' fate. Bcl-xL is one of anti-apoptotic protein in this family. In this study, a new Bcl-xL homolog (EcBcl-xL) was identified and characterized from orange-spotted grouper, Epinephelus coioides. EcBcl-xL encoded a 221 amino acid peptides that shared 86% identity to Larimichthys crocea Bcl-xL protein, contained four conserved BH domains and one transmembrane region. The predicted three-dimensional structure of EcBcl-xL was similar with Homo sapiens Bcl-xL. EcBcl-xL widely expressed in all tested tissues with highest expression in head kidney. Its expression level was significantly up-regulated after SGIV infection in vivo. Furthermore, overexpression of EcBcl-xL could inhibit SGIV-induced nonapoptotic cell death and suppressed viral genes transcriptions in GS cells. Our findings suggested that EcBcl-xL might play a role during virus infection through modulating SGIV-induced nonapoptotic cell death.

CD147 Induces Epithelial-to-Mesenchymal Transition by Disassembling Cellular Apoptosis Susceptibility Protein/E-Cadherin/β-Catenin Complex in Human Endometriosis

Epithelial-to-mesenchymal transition (EMT) is postulated to be a prerequisite for the establishment of endometriosis (EMS), a common reproductive disorder in women. Our previous studies have demonstrated the elevated expression of transmembrane glycoprotein CD147 and its prosurvival effect on abnormal cells in endometriosis. Intriguingly, CD147 is known to promote EMT in cancers. However, the involvement of CD147 in EMT during the establishment of endometriosis remains incompletely understood. We found that CD147 promotes EMT in human endometrial adenocarcinoma cell line Ishikawa. We identified a novel CD147-interacting partner, cellular apoptosis susceptibility protein (CAS), which stabilized the interaction between E-cadherin (E-cad) and β-catenin (β-cat) by forming the CAS/E-cad/β-cat complex. Down-regulation of CAS led to the release and nuclear translocation of β-cat from E-cad, resulting in the overexpression of the EMT-promoting gene SNAIL. Interestingly, overexpression of CD147 impaired the interaction between CAS and E-cad and triggered the release of β-cat from the CAS/E-cad/β-cat complex, which in turn led to EMT. Furthermore, CAS was down-regulated in EMS, with elevated levels of CD147 and nuclear β-cat. These findings suggest a previously undefined role of CAS in regulating EMT and reveal the involvement of a CD147-induced EMT signaling pathway in pathogenic progression of EMS.

CD147 regulates extrinsic apoptosis in spermatocytes by modulating NFκB signaling pathways

CD147 null mutant male mice are infertile with arrested spermatogenesis and increased apoptotic germ cells. Our previous studies have shown that CD147 prevents apoptosis in mouse spermatocytes but not spermatogonia. However, the underlying mechanism remains elusive. In the present study, we aim to determine the CD147-regulated apoptotic pathway in mouse spermatocytes. Our results showed that immunodepletion of CD147 triggered apoptosis through extrinsic apoptotic pathway in mouse testis and spermatocyte cell line (GC-2 cells), accompanied by activation of non-canonical NFκB signaling and suppression of canonical NFκB signaling. Furthermore, CD147 was found to interact with TRAF2, a factor known to regulate NFκB and extrinsic apoptotic signaling, and interfering CD147 led to the decrease of TRAF2. Consistently, depletion of CD147 by CRISPR/Cas9 technique in GC-2 cells down-regulated TRAF2 and resulted in cell death with suppressed canonical NFκB and activated non-canonical NFκB signaling. On the contrary, interfering of CD147 had no effect on NFκB signaling pathways as well as TRAF2 protein level in mouse spermatogonia cell line (GC-1 cells). Taken together, these results suggested that CD147 plays a key role in reducing extrinsic apoptosis in spermatocytes, but not spermatogonia, through modulating NFκB signaling pathway.

Upregulation of CFTR in patients with endometriosis and its involvement in NFκB-uPAR dependent cell migration

Endometriotic tissues exhibit high migration ability with the underlying mechanisms remain elusive. Our previous studies have demonstrated that cystic fibrosis transmembrane conductance regulator (CFTR) acts as a tumor suppressor regulating cell migration. In the present study, we explored whether CFTR plays a role in the development of human endometriosis. We found that both mRNA and protein expression levels of CFTR and urokinase-type plasminogen activator receptor (uPAR) were significantly increased in ectopic endometrial tissues from patients with endometriosis compared to normal endometrial tissues from women without endometriosis and positively correlated. In human endometrial Ishikawa (ISK) cells, overexpression of CFTR stimulated cell migration with upregulated NFκB p65 and uPAR. Knockdown of CFTR inhibited cell migration. Furthermore, inhibition of NFκB with its inhibitors (curcumin or Bay) significantly reduced the expression of uPAR and cell migration in the CFTR-overexpressing ISK cells. Collectively, the present results suggest that the CFTR-NFκB-uPAR signaling may contribute to the progression of human endometriosis, and indicate potential targets for diagnosis and treatment.

Regulation of apoptotic pathways during endometriosis: from the molecular basis to the future perspectives

PURPOSE

Endometriosis is defined as the presence of endometrial-like endometrial cells, glands and stroma outside the uterus, causing a strong inflammatory-like microenvironment in the affected tissue. This may provoke a breakdown in the peritoneal cavity homeostasis, with the consequent processes of immune alteration, documented by peripheral mononuclear cells recruitment and secretion of inflammatory cytokines in early phases and of angiogenic and fibrogenic cytokines in the late stages of the disease. Considering the pivotal role of interaction between immune and endometriotic cells, in this paper, we aim to shed light about the role of apoptosis pathways in modulating the fine-regulated peritoneal microenvironment during endometriosis.

METHODS

Narrative overview, synthesizing the findings of literature retrieved from searches of computerized databases.

RESULTS

In normal conditions, endometriotic cells, refluxed through the fallopian tubes into the peritoneal cavity, should be attacked and removed by phagocytes and NK cells. During endometriosis, the breakdown of peritoneal homeostasis causes the failure of scavenging mechanisms, allowing the survival of endometriotic cells. The consequent so-called "immunoescaping" of endometriotic cells could be due, at least in part, to the reduction of apoptotic-mediated pathways previously described.

CONCLUSION

Considering the large amount of evidence retrieved from in vitro as well as in vivo models, the reduced apoptosis of endometriotic cells together with the increased apoptosis of peritoneal fluid mononuclear cells may address the peritoneal homeostasis to a permissive environment for the progression of the disease.

Activated Hippo/Yes-Associated Protein Pathway Promotes Cell Proliferation and Anti-apoptosis in Endometrial Stromal Cells of Endometriosis

CONTEXT

The imbalance in cell proliferation and apoptosis is considered an important role in the pathogenesis of endometriosis, but the exact mechanisms remains unclear. A newly established signaling pathway–Hippo/Yes-associated protein (YAP) pathway plays a critical role in the proliferation and apoptosis processes. However, studies focusing on Hippo/YAP pathway and endometriosis are lacking.

OBJECTIVE

The objective was to explore the function of the Hippo/YAP pathway in endometriosis.

SETTING AND DESIGN

The expression of YAP was first investigated in endometrium of women with or without endometriosis. The role of YAP in cell proliferation and apoptosis is identified by transfection of endometrial stromal cells (ESCs) in vitro, subsequent Verteporfin treatments in eutopic ESCs in vitro, and endometriosis animal model of nude mice in vivo.

RESULTS

Our results revealed that increased expression of YAP and decreased expression of p-YAP in ectopic and eutopic endometrium compared with normal endometrium. YAP knockdown in eutopic ESCs decreased cell proliferation and enhanced cell apoptosis companied with decreased expression of TEAD1, CTGF, and B-cell lymphoma/leukemia (BCL)-2; whereas overexpression of YAP resulted in increased proliferation and decreased apoptosis of normal ESCs with increased expression of TEAD1, CTGF, and BCL-2. By chromatin immunoprecipitation qPCR CTGF and BCL-2 were identified as directly downstream target genes of YAP-TEAD1 active complex. Eutopic ESCs treated with Verteporfin revealed decreased proliferation and enhanced apoptosis whereas in endometriosis animal models of nude mice treated with Verteporfin, the size of endometriotic lesions was significantly reduced.

CONCLUSIONS

Our study suggests that the Hippo/YAP-signaling pathway plays a critical role in the pathogenesis of endometriosis and should present a novel therapeutic method against endometriosis.