β-Catenin activation contributes to the pathogenesis of adenomyosis through epithelial-mesenchymal transition

Adenomyotic Lesions Are Induced in the Mouse Uterus after Exposure to NSAID and EE2 Mixtures at Environmental Doses

The aim of this study was to assess the long-term effect of exposure to environmentally relevant doses of non-steroidal anti-inflammatory drugs (NSAIDs; ibuprofen, and diclofenac) and 17β-ethinylestradiol (EE2) on the mouse uterus. NSAID-EE2 mixtures were administered in the drinking water from gestational day 8 until 8 weeks post-birth (i.e., during embryo development, lactation, puberty, and sexual maturity). The incidence of adenomyosis lesions (presence of endometrial glands in the inner myometrium) increased up to 60% in the uterus of 8-week-old exposed females (F1) and to 85% in F2 females (exposed father). Histological analysis revealed aberrant proliferation and apoptosis, vacuolization of epithelial cells, and increased incidence of abnormal glands in the luminal and glandular epithelium in F1 and F2 uteri. Moreover, myofibroblast proportion (alpha-smooth muscle actin (α-SMA) expression analysis) and collagen expression (Picrosirius red stain; a fibrosis hallmark) were increased in F1 and F2 endometrium. Connexin-43 was aberrantly distributed in the endometrial stroma and glands of F1 and F2 uteri. Conversely, uterine 17β-estradiol and progesterone levels were not affected in F1 and F2 females. These findings demonstrated that in mice, chronic exposure to NSAID and EE2 mixtures at environmental doses intergenerationally affects uterine physiology, particularly the endometrium. It may serve as a model to study the pathophysiology of human adenomyosis.

Abnormal activation of the Wnt3a/β-catenin signaling pathway promotes the expression of T-box transcription factor 3(TBX3) and the epithelial-mesenchymal transition pathway to mediate the occurrence of adenomyosis

BACKGROUND

T-box transcription factor 3(TBX3) is a transcription factor that can regulate cell proliferation, apoptosis, invasion, and migration in different tumor cells; however, its role in adenomyosis (ADM) has not been previously studied. Some of ADM's pathophysiological characteristics are similar to those of malignant tumors (e.g., abnormal proliferation, migration, and invasion).

METHODS AND RESULTS

We hypothesized that TBX3 might have a role in ADM. We used tamoxifen-induced Institute of Cancer research (ICR) mice to establish ADM disease model. The study procedure included western blotting and immunohistochemistry to analyze protein levels; additionally, we used intraperitoneal injection of Wnt/β-catenin pathway inhibitor XAV-939 to study the relationship between TBX3 and Wnt/β-catenin pathway as well as Anti-proliferation cell nuclear antigen( PCNA) and TUNEL to detect cell proliferation and apoptosis, respectively. TBX3 overexpression and epithelial-to-mesenchymal transition (EMT) in ADM mice was found to be associated with activation of the Wnt3a/β-catenin pathway. Treatment with XAV-939 in ADM mice led to the inhibition of both TBX3 and EMT; moreover, abnormal cell proliferation was suppressed, the depth of invasion of endometrium cells was limited. Thus, the use of XAV-939 effectively inhibited further invasion of endometrial cells.

CONCLUSION

These findings suggest that TBX3 may play an important role in the development of ADM. The expression of TBX3 in ADM was regulated by the Wnt3a/β-catenin pathway. The activation of the Wnt3a/β-catenin pathway in ADM promoted TBX3 expression and induced the occurrence of EMT, thus promoting cell proliferation and inhibiting apoptosis, ultimately accelerating the development of ADM. The study provides a reference for the diagnosis of ADM.

The Evolving Spectrum of Endometrial Glandular Proliferations With Corded and Hyalinized Features

We present the clinicopathologic and immunohistochemical features of 14 endometrial glandular proliferations with conspicuous corded and hyalinized (CH) features comprised entirely or predominantly of endometrial hyperplasia. Endometrial glandular lesions ranged in severity from endometrial hyperplasia with and without cytologic atypia (5/14 [36%]) to hyperplasia with architectural complexity bordering on well-differentiated endometrioid adenocarcinoma (3/14 [21%]) to frank corded and hyalinized endometrial carcinoma ("CHEC") (6/14 [43%]). In addition to sex cord-like growth and hyalinized stroma, other common histologic features included prominent spindle cells (11/14 [79%]), keratinizing and/or morular squamous differentiation (10/14 [71%]), and osseous metaplasia (6/14 [43%]). Immunohistochemical characterization revealed aberrant nuclear beta-catenin in all cases (14/14 [100%]); additionally, all cases demonstrated positive estrogen receptors, intact PTEN, PMS2 and MSH6, and wild-type p53 expression. Patients ranged in age from 24 to 58 (mean 38) years. Of 5 patients with hyperplasia with CH features, 2 experienced complete resolution after progestin therapy and none progressed to adenocarcinoma (mean follow-up 15.6 mo, range 2 to 64). By contrast, of 2 patients with hyperplasia bordering on CHEC and with available follow-up, both subsequently developed adenocarcinoma, suggesting that even focal increased architectural complexity may predict an elevated risk of malignancy. We conclude that CH morphology is not limited to endometrioid carcinoma and may occur across a spectrum of neoplastic proliferations, including those without sufficient architectural complexity or cytologic atypia to warrant classification as adenocarcinoma. We propose the term "corded and hyalinized endometrial hyperplasia" to describe this precursor lesion and report favorable outcomes with conservative treatment.

The impact of fibronectin knockout on invasion and migration of endometrial cell in adenomyosis

The present study aimed to investigate the potential effect of fibronectin (FN) in adenomyosis progression. Small guide RNAs were designed to knock down FN expression in Ishikawa cells. The impact of FN on the proliferation, apoptosis, migration, and invasion of the cells was assessed. Cell proliferation was detected using a Celigo Imaging Cytometer system; apoptosis was quantified by flow cytometry; and cell migration and invasion were investigated via transwell assays. Cell proliferation was markedly suppressed in the FN knockout (KO) group compared with the control group, while apoptosis significantly increased. The levels of cell migration and invasion in the KO group were significantly decreased compared with the control group. Our study revealed that downregulation of FN expression is likely to restrain cell proliferation, migration, and invasion in endometrial cells in adenomyosis.

Molecular Targets for Nonhormonal Treatment Based on a Multistep Process of Adenomyosis Development

Adenomyosis is an estrogen-dependent gynecologic disease characterized by the presence of endometrial tissue within the myometrium. Adenomyosis presents with abnormal uterine bleeding, pelvic pains, and infertility. This review aimed to investigate the major estrogen downstream effectors involved in the process of adenomyosis development and their potential use for nonhormonal treatment. A literature search was performed for preclinical and clinical studies published between January 2010 and November 2021 in the PubMed and Google Scholar databases using a combination of specific terms. Adenomyosis presents with a wide spectrum of clinical manifestations from asymptomatic to severe through a complex process involving a series of molecular changes associated with inflammation, invasion, angiogenesis, and fibrosis. Adenomyosis may develop through a multistep process, including the acquisition of (epi)genetic mutations, tissue injury caused at the endometrial-myometrial interface, inside-to-outside invasion (from the endometrial side into the uterine wall), or outside-to-inside invasion (from the serosal side into the uterine wall), and epithelial-mesenchymal transition, tissue repair or remodeling in the myometrium. These processes can be regulated by increased estrogen biosynthesis and progesterone resistance. The expression of estrogen downstream effectors associated with persistent inflammation, fragile and more permeable vessel formation, and tissue injury and remodeling may be correlated with dysmenorrhea, heavy menstrual bleeding, and infertility, respectively. Key estrogen downstream targets (e.g., WNT/β-catenin, transforming growth factor-β, and nuclear factor-κB) may serve as hub genes. We reviewed the molecular mechanisms underlying the development of adenomyosis and summarized potential nonhormonal therapies.

Adenomyosis: single-cell transcriptomic analysis reveals a paracrine mesenchymal-epithelial interaction involving the WNT/SFRP pathway

OBJECTIVE

To assess the cellular and molecular landscape of adenomyosis.

DESIGN

Single-cell analysis of genome-wide messenger RNA (mRNA) expression (single-cell RNA sequencing) of matched tissues of endometrium, adenomyosis, and myometrium using relatively large numbers of viable cells.

SETTING

Not applicable.

PATIENT(S)

Patients (n = 3, age range 40-44 years) undergoing hysterectomy for diffuse adenomyosis.

MAIN OUTCOME MEASURE(S)

Definition of the molecular landscape of matched adenomyotic, endometrial and myometrial tissues from the same uterus using single-cell RNA sequencing and comparison of distinct cell types in these tissues to identify disease-specific cell populations, abnormal gene expression and pathway activation, and mesenchymal-epithelial interactions.

RESULT(S)

The largest cell population in the endometrium was composed of closely clustered fibroblast groups, which comprise 36% of all cells and seem to originate from pericyte progenitors differentiating to estrogen/progesterone receptor-expressing endometrial stromal- cells. In contrast, the entire fibroblast population in adenomyosis comprised a larger (50%) portion of all cells and was not linked to any pericyte progenitors. Adenomyotic fibroblasts eventually differentiate into extracellular matrix protein-expressing fibroblasts and smooth muscle cells. Hierarchical clustering of mRNA expression revealed a unique adenomyotic fibroblast population that clustered transcriptomically with endometrial fibroblasts, suggestive of an endometrial stromal cell population serving as progenitors of adenomyosis. Four other adenomyotic fibroblast clusters with disease-specific transcriptomes were distinct from those of endometrial or myometrial fibroblasts. The mRNA levels of the natural WNT inhibitors, named, secreted frizzled-related proteins 1, 2, and 4, were higher in these 4 adenomyotic fibroblast clusters than in endometrial fibroblast clusters. Moreover, we found that multiple WNTs, which originate from fibroblasts and target ciliated and unciliated epithelial cells and endothelial cells, constitute a critical paracrine signaling network in adenomyotic tissue. Compared with endometrial tissue, unciliated and ciliated epithelial cells in adenomyosis comprised a significantly smaller portion of this tissue and exhibited molecular evidence of progesterone resistance and diminished regulation of estrogen signaling.

CONCLUSION(S)

We found a high degree of heterogeneity in fibroblast-like cells in the adenomyotic uterus. The WNT signaling involving differential expression of secreted frizzled-related proteins, which act as decoy receptors for WNTs, in adenomyotic fibroblasts may have a key role in the pathophysiology of this disease.

MIR503HG silencing promotes endometrial stromal cell progression and metastasis and suppresses apoptosis in adenomyosis by activating the Wnt/β‑catenin pathway via targeting miR‑191

MIR503HG is a 786 bp long lncRNA located on chromosome Xq26.3, and it can regulate diverse cellular processes. The pathogenesis of adenomyosis (AD) is associated with endometrial stromal cells (ESCs). The present study investigated the specific role of MIR503HG in AD pathogenesis and progression using ESCs derived from the endometrium of patients with AD as a model. Expression of MIR503HG and microRNA (miR)-191 were assessed using reverse transcription-quantitative PCR. An immunocytochemistry assay was used to detect cytokeratin- or vimentin-positive ESCs. Transfections of ESCs with MIR503HG overexpression plasmid, short hairpin-MIR503HG and miR-191 inhibitor were performed. ESC viability, migration, invasion and apoptosis were evaluated using Cell Counting Kit-8, Transwell and flow cytometry assays. The association between MIR503HG and miR-191 was predicted by StarBase and confirmed using a dual-luciferase reporter assay. Expression of epithelial-mesenchymal transition-related markers (E-cadherin and N-cadherin) and Wnt/β-catenin pathway-related molecules (β-catenin) in ESCs were analyzed by western blotting. The isolated ESCs were vimentin-positive and cytokeratin-negative. MIR503HG was lowly expressed in the endometrial tissues derived from patients with AD. MIR503HG overexpression hindered ESC viability, migration and invasion while enhancing the apoptosis and downregulating miR-191 expression. MIR503HG knockdown induced the opposite effects, accompanied by downregulation of the E-cadherin expression and upregulation of N-cadherin and β-catenin levels. MIR503HG directly targeted miR-191 that was highly expressed in endometrial tissues derived from patients with AD. In ESCs, downregulation of miR-191 inhibited the viability, migration and invasion and the expression of N-cadherin and β-catenin levels while enhancing the apoptosis and E-cadherin expression in ESCs. Moreover, downregulation of miR-191 partially reversed the effect of MIR503HG knockdown. Collectively, overexpressed MIR503HG impeded the proliferation and migration of ESCs derived from endometrium of patients with AD, while promoting apoptosis via inhibition of the Wnt/β-catenin pathway via targeting miR-191.

Cracking the enigma of adenomyosis: an update on its pathogenesis and pathophysiology

In brief

Traditionally viewed as enigmatic and elusive, adenomyosis is a fairly common gynecological disease but is under-recognized and under-researched. This review summarizes the latest development on the pathogenesis and pathophysiology of adenomyosis, which have important implications for imaging diagnosis of the disease and for the development of non-hormonal therapeutics.

Abstract

Traditionally considered as an enigmatic disease, adenomyosis is a uterine disease that affects many women of reproductive age and is a contributing factor for pelvic pain, heavy menstrual bleeding (HMB), and subfertility. In this review, the new development in the pathogenesis and pathophysiology of adenomyosis has been summarized, along with their clinical implications. After reviewing the progress in our understanding of the pathogenesis and describing the prevailing theories, in conjunction with their deficiencies, a new hypothesis, called endometrial-myometrial interface disruption (EMID), which is backed by extensive epidemiologic data and demonstrated by a mouse model, is reviewed, along with recent data implicating the role of Schwann cells in the EMI area in the genesis of adenomyosis. Additionally, the natural history of adenomyotic lesions is elaborated and underscores that, in essence, adenomyotic lesions are fundamentally wounds undergoing repeated tissue injury and repair (ReTIAR), which progress to fibrosis through epithelial-mesenchymal transition, fibroblast-to-myofibroblast transdifferentiation, and smooth muscle metaplasia. Increasing lesional fibrosis propagates into the neighboring EMI and endometrium. The increased endometrial fibrosis, with ensuing greater tissue stiffness, results in attenuated prostaglandin E2, hypoxia signaling and glycolysis, impairing endometrial repair and causing HMB. Compared with adenomyosis-associated HMB, the mechanisms underlying adenomyosis-associated pain are less understood but presumably involve increased uterine contractility, hyperinnervation, increased lesional production of pain mediators, and central sensitization. Viewed through the prism of ReTIAR, a new imaging technique can be used to diagnose adenomyosis more accurately and informatively and possibly help to choose the best treatment modality.

Estrogen-increased SGK1 Promotes Endometrial Stromal Cell Invasion in Adenomyosis by Regulating with LPAR2

Adenomyosis is an estrogen-dependent gynecological disorder. The abnormal migration and invasion of the eutopic endometrium is thought to be the primary role in the pathogenesis of adenomyosis. However, the exact underlying mechanism remains unclear. This study investigated involvement of serum and glucocorticoid-regulated kinase 1 (SGK1) in the pathogenesis of adenomyosis. The SGK1 expression level was higher in the eutopic endometrium of adenomyosis. Upregulation of SGK1 can promote the migration, invasion of human stromal endometrial cells (HESC). Through RNA sequencing and other technical methods, we found that SGK1 regulates the expression of the important downstream molecule Lysophosphatidic acid receptor 2 (LPAR2), and ultimately regulates the expression level of functional proteins such as matrix metalloproteinase 2 and matrix metalloproteinase 9, which are related to migration and invasion. Then, we found that 17β-estradiol (E₂) upregulated the expression of SGK1 in endometrial cells in a dose-dependent manner. Furthermore, SGK1 shRNA significantly suppressed the migration and invasion induced by E₂ in endometrial cells, as well as the related factors. Our study revealed the possible role of SGK1 in the migration and invasion in the development of adenomyosis.

Perioperative Suppression of Schwann Cell Dedifferentiation Reduces the Risk of Adenomyosis Resulting from Endometrial–Myometrial Interface Disruption in Mice

We have recently demonstrated that endometrial–myometrial interface (EMI) disruption (EMID) can cause adenomyosis in mice, providing experimental evidence for the well-documented epidemiological finding that iatrogenic uterine procedures increase the risk of adenomyosis. To further elucidate its underlying mechanisms, we designed this study to test the hypothesis that Schwann cells (SCs) dedifferentiating after EMID facilitate the genesis of adenomyosis, but the suppression of SC dedifferentiation perioperatively reduces the risk. We treated mice perioperatively with either mitogen-activated protein kinase kinase (MEK)/extracellular-signal regulated protein kinase (ERK) or c-Jun N-terminal kinase (JNK) inhibitors or a vehicle 4 h before and 24 h, 48 h and 72 h after the EMID procedure. We found that EMID resulted in progressive SCs dedifferentiation, concomitant with an increased abundance of epithelial cells in the myometrium and a subsequent epithelial–mesenchymal transition (EMT). This EMID-induced change was abrogated significantly with perioperative administration of JNK or MEK/ERK inhibitors. Consistently, perioperative administration of a JNK or a MEK/ERK inhibitor reduced the incidence by nearly 33.5% and 14.3%, respectively, in conjunction with reduced myometrial infiltration of adenomyosis and alleviation of adenomyosis-associated hyperalgesia. Both treatments significantly decelerated the establishment of adenomyosis and progression of EMT, fibroblast-to-myofibroblast trans-differentiation and fibrogenesis in adenomyotic lesions. Thus, we provide the first piece of evidence strongly implicating the involvement of SCs in the pathogenesis of adenomyosis induced by EMID.

Overexpression of Human Estrogen Biosynthetic Enzyme Hydroxysteroid (17beta) Dehydrogenase Type 1 Induces Adenomyosis-like Phenotype in Transgenic Mice

Hydroxysteroid (17beta) dehydrogenase type 1 (HSD17B1) is an enzyme that converts estrone to estradiol, while adenomyosis is an estrogen-dependent disease with poorly understood pathophysiology. In the present study, we show that mice universally over-expressing human estrogen biosynthetic enzyme HSD17B1 (HSD17B1TG mice) present with adenomyosis phenotype, characterized by histological and molecular evaluation. The first adenomyotic changes with endometrial glands partially or fully infiltrated into the myometrium appeared at the age of 5.5 months in HSD17B1TG females and became more prominent with increasing age. Preceding the phenotype, increased myometrial smooth muscle actin positivity and increased amount of glandular myofibroblast cells were observed in HSD17B1TG uteri. This was accompanied by transcriptomic upregulation of inflammatory and estrogen signaling pathways. Further, the genes upregulated in the HSD17B1TG uterus were enriched with genes previously observed to be induced in the human adenomyotic uterus, including several genes of the NFKB pathway. A 6-week-long HSD17B1 inhibitor treatment reduced the occurrence of the adenomyotic changes by 5-fold, whereas no effect was observed in the vehicle-treated HSD17B1TG mice, suggesting that estrogen is the main upstream regulator of adenomyosis-induced uterine signaling pathways. HSD17B1 is considered as a promising drug target to inhibit estrogen-dependent growth of endometrial disorders. The present data indicate that HSD17B1 over-expression in TG mice results in adenomyotic changes reversed by HSD17B1 inhibitor treatment and HSD17B1 is, thus, a potential novel drug target for adenomyosis.

Unveiling the Pathogenesis of Adenomyosis through Animal Models

Background: Adenomyosis is a common gynecological disorder traditionally viewed as “elusive”. Several excellent review papers have been published fairly recently on its pathogenesis, and several theories have been proposed. However, the falsifiability, explanatory power, and predictivity of these theories are often overlooked. Since adenomyosis can occur spontaneously in rodents and many other species, the animal models may help us unveil the pathogenesis of adenomyosis. This review critically tallies experimentally induced models published so far, with a particular focus on their relevance to epidemiological findings, their possible mechanisms of action, and their explanatory and predictive power. Methods: PubMed was exhaustively searched using the phrase “adenomyosis and animal model”, “adenomyosis and experimental model”, “adenomyosis and mouse”, and “adenomyosis and rat”, and the resultant papers were retrieved, carefully read, and the resultant information distilled. All the retrieved papers were then reviewed in a narrative manner. Results: Among all published animal models of adenomyosis, the mouse model of adenomyosis induced by endometrial–myometrial interface disruption (EMID) seems to satisfy the requirements of falsifiability and has the predictive capability and also Hill’s causality criteria. Other theories only partially satisfy Hill’s criteria of causality. In particular, animal models of adenomyosis induced by hyperestrogenism, hyperprolactinemia, or long-term exposure to progestogens without much epidemiological documentation and adenomyosis is usually not the exclusive uterine pathology consequent to those induction procedures. Regardless, uterine disruption appears to be a necessary but not sufficient condition for causing adenomyosis. Conclusions: EMID is, however, unlikely the sole cause for adenomyosis. Future studies, including animal studies, are warranted to understand how and why in utero and/or prenatal exposure to elevated levels of estrogen or estrogenic compounds increases the risk of developing adenomyosis in adulthood, to elucidate whether prolactin plays any role in its pathogenesis, and to identify sufficient condition(s) that cause adenomyosis.

Cyanidin-3-O-glucoside ameliorates cadmium induced uterine epithelium proliferation in mice

Cadmium (Cd) is an environmental pollutant and endocrine disrupter, abundantly present in water, food, and soil. Accumulation of Cd in the body can negatively affect female reproduction; especially the uterus is exceptionally sensitive to the toxic actions of Cd. The anthocyanin cyanidin-3-O-glucoside (C3G) is a naturally occurring phenolic compound in fruits and plants that can antagonize the toxic effects of Cd. This capacity makes C3G a possible candidate to prevent Cd-induced female infertility. The present study aimed to investigate: 1) whether C3G intake could prevent Cd-induced female reproductive toxicity, and 2) the underlying mechanisms responsible for this protective effect. The results of our study indicated that Cd exposure did not affect ovarian function, but induced hypertrophy of the uterine endometrium. Oral intake of C3G markedly reduced the effects of Cd exposure on the thickness of the uterine epithelium cells. Transcriptomic analysis of the endometrium revealed that C3G intake had anti-estrogenic effects, attenuating Cd-induced endometrial epithelial cell proliferation by inhibiting estrogen-responsive genes, enhancing epithelial progesterone receptor expression, and regulating Klf4 expression. The current findings implicate that C3G has the potential to be used as a dietary supplement based on its capacity to intervene in Cd-induced female reproductive toxicity.

Mode Switch of Ca2 + Oscillation-Mediated Uterine Peristalsis and Associated Embryo Implantation Impairments in Mouse Adenomyosis

Adenomyosis is a debilitating gynecological disease of the uterus with no medicinal cure. The tissue injury and repair hypothesis for adenomyosis suggests that uterine hyperperistalsis or dysperistalsis plays a pivotal role in establishing adenomyotic lesions. However, specific impairments in uterine peristalsis and the underlying cellular signals for these changes in adenomyosis remain elusive. Here, we report a precision-cut uterine slice preparation that preserves in vivo uterine architecture and generates peristalsis similar to that seen in the whole uterus. We found that uterine peristalsis in neonatal mice at day 14 and adult mice at day 55 presents as bursts with multiple peaks induced by intracellular Ca²⁺ oscillations. Using a mouse model of adenomyosis induced by tamoxifen, a selective estrogen receptor modulator, we discovered that uterine peristalsis and Ca²⁺ oscillations from adenomyotic uteri on days 14 and 55 become spikes (single peaks) with smaller amplitudes. The peak frequency of Ca²⁺ oscillations or peristalsis does not show a difference between control and adenomyotic mice. However, both the estimated force generated by uterine peristalsis and the total Ca²⁺ raised by Ca²⁺ oscillations are smaller in uteri from adenomyotic mice. Uteri from adenomyotic mice on day 14, but not on day 55, exhibit hyperresponsiveness to oxytocin. Embryo implantations are decreased in adenomyotic adult mice. Our results reveal a mode switch from bursts to spikes (rather than an increased peak frequency) of uterine Ca²⁺ oscillations and peristalsis and concurrent hyperresponsiveness to oxytocin in the neonatal stage are two characteristics of adenomyosis. These characteristics may contribute to embryo implantation impairments and decreased fertility in adenomyosis.

Corded and Hyalinized Endometrioid Adenocarcinoma (CHEC) of the Uterine Corpus are Characterized by CTNNB1 Mutations and Can Show Adverse Clinical Outcomes

Corded and hyalinized endometrioid adenocarcinoma (CHEC) is a morphologic variant of endometrioid adenocarcinoma that is typically low-grade [International Federation of Gynecology and Obstetrics (FIGO) grade 1-2]. CHEC exhibits a biphasic appearance with gland forming adenocarcinoma merging with a diffuse component with corded growth often in a hyalinized matrix; squamous differentiation is frequent and osteoid production can be seen. This morphologic appearance can invoke a large differential diagnosis including carcinosarcoma. CHEC is thought to be associated with good clinical outcome although the available data is sparse. We performed detailed clinical, morphologic, immunohistochemical, and molecular analyses on a cohort of 7 CHEC. Six cases exhibited features of classic low-grade CHEC while one case showed greater cytologic atypia (high-grade CHEC). Patient age ranged from 19 to 69 yr. Four patients presented at stage I, 2 at stage II, and 1 at stage III. All tumors demonstrated nuclear staining for beta-catenin and loss of E-cadherin in the corded and hyalinized component. There was relative loss of epithelial markers. Loss of PTEN and ARID1A was seen in 4 and 3 tumors, respectively, and 1 tumor displayed loss of MLH1 and PMS2. Next-generation sequencing revealed CTNNB1 and PI3K pathway mutations in all 7 cases with TP53 and RB1 alterations in the high-grade CHEC. Clinical follow-up was available for 6 patients; 2 died of disease (48 and 50 mo), 2 are alive with disease (both recurred at 13 mo), and 2 have no evidence of disease (13 and 77 mo). Our study shows that CHEC universally harbors CTNNB1 mutations with nuclear staining for beta-catenin, can rarely show high-grade cytology, and can be associated with adverse clinical outcomes.

Hypo-Expression of Tuberin Promotes Adenomyosis via the mTOR1-Autophagy Axis

Adenomyosis (AM) is a disease in which endometrial tissue invades the myometrium and has a 10–60% prevalence in reproductive-aged women. TSC2 regulates autophagy via mTOR1 signalling in colorectal cancer and endometrial carcinoma. Dysregulation of autophagy is implicated in adenomyosis pathogenesis. However, whether TSC2 participates in adenomyosis via autophagy remains obscure. Here, we found that the expression of TSC2 in adenomyosis was significantly decreased than that in normal endometrium during the secretory phase. Moreover, TSC2 and autophagy marker expression was significantly lower in ectopic lesions than in eutopic samples. TSC2 downregulation inhibited autophagy through mTOR1 signalling pathway activation in endometrial cells, leading to excessive proliferation, migration, and EMT; TSC2 overexpression induced the opposite effects. Rapamycin treatment suppressed cell proliferation, migration and EMT in the absence of TSC2. In parallel, an autophagy-specific inhibitor (SAR-405) restored migration and EMT under rapamycin treatment in TSC2-knockdown Ishikawa cells. Finally, SAR-405 treatment promoted EMT and migration of overexpressing cells. Collectively, our results suggest that TSC2 controls endometrial epithelial cell migration and EMT by regulating mTOR1-autophagy axis activation and that hypo-expression of TSC2 in the endometrium might promote adenomyosis.

High-intensity focused ultrasound in the management of adenomyosis: long-term results from a single center

OBJECTIVE

To investigate the long-term clinical outcomes of patients with adenomyosis treated by high-intensity focused ultrasound (HIFU).

MATERIALS AND METHODS

From June 2012 to January 2020, 2311 patients with adenomyosis were treated with HIFU at our center, 1982 patients who have complete clinical data were retrospectively reviewed. Among the patients who completed the follow-up, 485 were treated with HIFU alone, 289 were treated with HIFU followed by GnRH-a, 255 were treated with HIFU combined with Mirena and 594 were treated with HIFU combined with GnRH-a and Mirena. The dysmenorrhea severity pain score and average menorrhagia severity score before and at 3 months, 6 months, 1 year, 2 years, 3 years and 5 years after HIFU were compared. The adverse effects were recorded. In addition, the efficacy between patients treated with GnRH-a and/or Mirena were compared.

RESULTS

After HIFU ablation, the dysmenorrhea severity pain score and the menorrhagia severity score were significantly decreased at each follow-up time point. However, it was observed that as the follow-up time increased, the effective rate of HIFU treatment in improving dysmenorrhea and menorrhagia decreased. The 6 months and 3 years follow-up results showed that the efficacy of HIFU combined with Mirena and HIFU combined with GnRH-a and Mirena were significantly higher than HIFU alone and HIFU combined with GnRH-a (p < 0.05). The major complications were rare.

CONCLUSION

HIFU is a safe and effective treatment for patients with adenomyosis. HIFU combined with Mirena or HIFU combined with GnRH-a and Mirena can significantly enhance the long-term treatment results.

An axonemal alteration in apical endometria of human adenomyosis

STUDY QUESTION

Is there any change in the distribution of microvilli and microtubules in the apical endometria of women with adenomyosis?

SUMMARY ANSWER

We observed microvilli damage in the apical endometria and an axonemal alteration characterized by abnormal distribution of longitudinal bundles of microtubules within microvilli in women with adenomyosis.

WHAT IS KNOWN ALREADY

Human adenomyosis has a negative impact on female fertility. Abnormal utero-tubal sperm transport, tissue inflammation and toxic effect of chemical mediators have been proposed as contributing factors. Inflammation-induced damage of mucosal cilia in the Fallopian tube has been reported. However, information on inflammation-induced damage of microvilli on the apical endometrial cells and its core bundles of microtubules in adenomyosis remains unknown.

STUDY DESIGN, SIZE, DURATION

This is a prospective cohort study with subjects undergoing laparoscopic surgery or hysterectomy for clinical indication and evaluations of endometrial biopsy samples in two academic university hospitals. During the period between March 2015 and December 2018, endometrial biopsy samples were prospectively collected from 15 control women and 45 women with adenomyosis for immunohistochemical analysis and a separate cohort of 10 control women with cervical intraepithelial neoplasia Grade 3 (CIN3) and 20 women with adenomyosis for analysis by immunohistochemistry and transmission electron microscopy (TEM).

PARTICIPANTS/MATERIALS, SETTING, METHODS

For immunohistochemical study, endometrial biopsy samples were prospectively collected from 15 control women with fibroids, 25 women with focal adenomyosis and 20 women with diffuse adenomyosis after surgery. The diagnosis of fibroid and adenomyosis was made clinically by transvaginal ultrasonography and magnetic resonance imaging and confirmed by histology. Immunohistochemical analysis was performed retrospectively using antibody against CD68 (marker of macrophages) in endometrial biopsy specimens of women with and without adenomyosis. TEM was performed with the apical endometria collected from a separate cohort of 10 control women with CIN3 and 20 women with focal and diffuse adenomyosis for the identification of any change in the distribution of microvilli and longitudinal bundles of microtubules within microvilli.

MAIN RESULTS AND ROLE OF CHANCE

Comparing to control endometria and contralateral side, tissue infiltration of macrophages (Mφ) in the endometria was significantly higher on the ipsilateral side of focal adenomyosis (P = 0.02 and P = 0.03, respectively) and anterior/posterior walls of diffuse adenomyosis (P = 0.01 for both). In a subgroup analysis of patients with focal adenomyosis with and without symptoms, the endometria of symptomatic women displayed a tendency of higher Mφ infiltration on the ipsilateral side than in asymptomatic women (P = 0.07). Comparing to contralateral side endometria of symptomatic women, Mφ infiltration was significantly higher in the endometria of symptomatic women collected from the ipsilateral side of focal adenomyosis (P = 0.03). We found a significantly less tissue infiltration of Mφ in the endometria of women with CIN3 than that in endometria of women with focal adenomyosis. TEM analysis showed that number of microvilli in the endometria was significantly decreased on the ipsilateral side (P = 0.003) comparing to that on the contralateral side of focal adenomyosis. The Chi-squared test indicated that cases with abnormal (disruption in the normal arrangement of 9 peripheral pairs + 1 central pair) microtubules (MT) were significantly higher in women with adenomyosis than in cases with normal patterns (P = 0.0016). While contralateral side displayed significantly less abnormal MT (P = 0.0002), ipsilateral side of focal adenomyosis showed significantly higher abnormal MT (P = 0.0164) comparing to normal patterns. Cases with symptomatic adenomyosis showed significantly higher abnormal MT than normal MT (P = 0.0004). An axonemal alteration characterized by abnormal structural distribution of microtubules within microvilli in the apical endometria in response to endometrial inflammation may be involved in adverse reproductive outcome in women with adenomyosis.

LIMITATIONS, REASONS FOR CAUTION

The average age of women in this study was high that may be associated with overall decline in fertility regardless of the presence or absence of adenomyosis or endometriosis. We collected endometrial biopsy samples from two completely separate cohorts of women for analysis by immunohiostochemistry and TEM. We need future follow-up study with increased sample size and from the same patients to precisely clarify the mechanistic link between axonemal alteration and negative fertility outcome.

WIDER IMPLICATIONS OF THE FINDINGS

Our current findings may have some biological implication to better understand the endometrial epithelial biology and pathology in women with adenomyosis and may open the avenue for future study in other reproductive diseases. The ultra-structural abnormalities of microvilli and microtubules in the apical endometria in response to tissue inflammatory reaction may clarify the possible association between negative fertility outcome and adenomyosis. Our findings may be clinically useful during counseling with symptomatic patients with adenomyosis desiring pregnancy.

STUDY FUNDING/COMPETING INTEREST (S)

This work was supported by Grants-in-Aid for Scientific Research from the Ministry of Education, Sports, Culture, Science and Technology of Japan. There is no conflict of interest related to this study.

TRIAL REGISTRATION NUMBER

N/A.

Upregulated Talin1 synergistically boosts β-estradiol-induced proliferation and pro-angiogenesis of eutopic and ectopic endometrial stromal cells in adenomyosis

Adenomyosis (ADS) is an estrogen-dependent gynecological disease with unspecified etiopathogenesis. Local hyperestrogenism may serve a key role in contributing to the origin of ADS. Talin1 is mostly identified to be overexpressed and involved in the progression of numerous human carcinomas through mediating cell proliferation, adhesion and motility. Whether Talin1 exerts an oncogenic role in the pathogenesis of ADS and puts an extra impact on the efficacy of estrogen, no relevant data are available yet. Here we demonstrated that the adenomyotic eutopic and ectopic endometrial stromal cells (ADS_Eu_ESC and ADS_Ec_ESC) treated with β-estradiol (β-E₂) presented stronger proliferative and pro-angiogenetic capacities, accompanied by increased expression of PCNA, Ki67, VEGFB and ANGPTL4 proteins. Meanwhile, these promoting effects were partially abrogated by Fulvestrant (ICI 182780, an estrogen-receptor antagonist). Aberrantly upregulation of Talin1 mRNA and protein level was observed in ADS endometrial specimens and stromal cells. Through performing functional experiments in vitro, we further determined that merely overexpression of Talin1 (OV-Talin1) also enhanced ADS stromal cell proliferation and pro-angiogenesis, while the most pronounced facilitating effects were found in the co-intervention group of OV-Talin1 plus β-E₂ treatment. Results from the xenograft nude mice model showed that the hypodermic endometrial lesions from co-intervention group had the highest mean weight and volume, compared with that of individual OV-Talin1 or β-E₂ treatment. The expression levels of PCNA, Ki67, VEGFB and ANGPTL4 in the lesions were correspondingly elevated the most in the co-intervention group. Our findings unveiled that overexpressed Talin1 might cooperate withβ-E₂ in stimulating ADS endometrial stromal cell proliferation and neovascularization, synergistically promoting the growth and survival of ectopic lesions. These results may be beneficial to provide a new insight for clarifying the pathogenesis of ADS.

In the mouse, prostaglandin D2 signalling protects the endometrium against adenomyosis

Adenomyosis is characterised by epithelial gland and mesenchymal stroma invasion of the uterine myometrium. Adenomyosis is an oestrogen-dependent gynaecological disease in which a number of factors, such as inflammatory molecules, prostaglandins (PGs), angiogenic factors, cell proliferation and extracellular matrix remodelling proteins, also play a role as key disease mediators. In this study, we used mice lacking both lipocalin and hematopoietic-PG D synthase (L- and H-Pgds) genes in which PGD2 is not produced to elucidate PGD2 roles in the uterus. Gene expression studied by real-time PCR and hormone dosages performed by ELISA or liquid chromatography tandem mass spectroscopy in mouse uterus samples showed that components of the PGD2 signalling pathway, both PGDS and PGD2-receptors, are expressed in the mouse endometrium throughout the oestrus cycle with some differences among uterine compartments. We showed that PGE2 production and the steroidogenic pathway are dysregulated in the absence of PGD2. Histological analysis of L/H-Pgds-/- uteri, and immunohistochemistry and immunofluorescence analyses of proliferation (Ki67), endothelial cell (CD31), epithelial cell (pan-cytokeratin), myofibroblast (α-SMA) and mesenchymal cell (vimentin) markers, identify that 6-month-old L/H-Pgds-/- animals developed adenomyotic lesions, and that disease severity increased with age. In conclusion, this study suggests that the PGD2 pathway has major roles in the uterus by protecting the endometrium against adenomyosis development. Additional experiments, using for instance transcriptomic approaches, are necessary to fully determine the molecular mechanisms that lead to adenomyosis in L/H-Pgds-/- mice and to confirm whether this strain is an appropriate model for studying the human disease.

Adenomyosis is associated with specific proton nuclear magnetic resonance (1H-NMR) serum metabolic profiles

OBJECTIVE

To determine whether the adenomyosis phenotype affects the proton nuclear magnetic resonance (¹H-NMR)-based serum metabolic profile of patients.

DESIGN

Cohort study.

SETTING

University hospital-based research center.

PATIENTS

Seventy-seven patients who underwent laparoscopy for a benign gynecologic condition.

INTERVENTIONS

Pelvic magnetic resonance imaging and collection of a venous peripheral blood sample were performed during the preoperative workup. The women were allocated to the adenomyosis group (n = 32), or the control group (n = 45). The adenomyosis group was further subdivided into two groups: diffuse adenomyosis of the inner myometrium (n = 14) and focal adenomyosis of the outer myometrium (n = 18). Other adenomyosis phenotypes were excluded.

MAIN OUTCOME MEASURES

Metabolomic profiling based on ¹H-NMR spectroscopy in combination with statistical approaches.

RESULTS

The serum metabolic profiles of the patients with adenomyosis indicated lower concentrations of 3-hydroxybutyrate, glutamate, and serine compared with controls. Conversely, the concentrations of proline, choline, citrate, 2-hydroxybutyrate, and creatinine were higher in the adenomyosis group. The focal adenomyosis of the outer myometrium and the diffuse adenomyosis phenotypes also each exhibited a specific metabolic profile.

CONCLUSION

Serum metabolic changes were detected in women with features of adenomyosis compared with their disease-free counterparts, and a number of specific metabolic pathways appear to be engaged according to the adenomyosis phenotype. The metabolites with altered levels are particularly involved in immune activation as well as cell proliferation and cell migration. Nevertheless, this study did find evidence of a correlation between metabolite levels and symptoms thought to be related to adenomyosis. Further studies are required to determine the clinical significance of these differences in metabolic profiles.

Comparative Transcriptomic Analysis to Identify the Important Coding and Non-coding RNAs Involved in the Pathogenesis of Pterygium

Pterygium is a common ocular surface disease characterized by abnormal fibrovascular proliferation and invasion, similar to tumorigenesis. The formation of tumors is related to a change in the expression of various RNAs; however, whether they are involved in the formation and development of pterygium remains unclear. In this study, transcriptome analysis of messenger RNAs (mRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) of paired pterygium and normal conjunctiva was performed to explore key genes regulating the development of pterygium. In total, 579 mRNAs, 275 lncRNAs, and 21 circRNAs were differentially expressed (DE) in pterygium compared with paired conjunctival tissues. Functional enrichment analysis indicated that DE RNAs were associated with extracellular matrix organization, blood vessel morphogenesis, and focal adhesion. Furthermore, through protein-protein interaction network and mRNA-lncRNA co-expression network analysis, key mRNAs including FN1, VCAM1, and MMP2, and key lncRNAs including MIR4435-2HG and LINC00968 were screened and might be involved in the pathogenesis of pterygium. In addition, several circRNAs including hsa_circ_0007482 and hsa_circ_001730 were considered to be involved in the pterygium development. This study provides a scientific basis for elucidating the pathogenesis of pterygium and will be beneficial for the development of preventive and therapeutic strategies.

TGF-β1 Neutralization Improves Pregnancy Outcomes by Restoring Endometrial Receptivity in Mice with Adenomyosis

The objective of this research is to study the effects of TGF-β1 inhibition on endometrial receptivity and pregnancy outcomes in mice with adenomyosis. Experiments were done using a mouse model of adenomyosis which took place in a hospital-affiliated laboratory. The mouse model used for this research is ICR mouse. Adenomyosis was induced by oral gavage of tamoxifen (TAM) from postnatal days (PNDs) 1 to 4 in ICR mice. Bilateral intrauterine injection of anti-TGF-β1-neutralizing antibody or isotype IgG or PBS was performed at PND42. The mice were then either sacrificed or mated at PND64 followed by sacrificing at gestational day (GD) 4 or proceeding to delivery. Implantation numbers, rate of dams with live birth, live birth numbers, survival at 1 week old, and pup mortality rate after weaning were recorded. Collagen was demonstrated by Masson's trichrome and Van Gieson's stains. Uterine expression of a receptivity marker, leukemia inhibitory factor (LIF), was examined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), Western blot, and immunohistochemistry (IHC). Anti-TGF-β1 treatment increased the mean implantation numbers, fecundity rate, the rate of dams with live birth, pup survival rate at 1 week old, and pup mortality rate after weaning. Collagen expression in uteri with adenomyosis was attenuated by anti-TGF-β1 treatment. Increased LIF expression by anti-TGF-β1 treatment was detected by qRT-PCR, Western blot, and IHC. The results suggest that inhibition of TGF-β1 improves pregnancy outcomes by restoring endometrial receptivity in mice with adenomyosis.

Talin1 Induces Epithelial-Mesenchymal Transition to Facilitate Endometrial Cell Migration and Invasion in Adenomyosis Under the Regulation of microRNA-145-5p

Adenomyosis (ADS) is a commonly encountered benign gynecological disorder. Epithelial-mesenchymal transition (EMT) may serve a pivotal role in the pathogenesis of ADS. Talin1 has been identified to be implicated in multiple human carcinomas, probably through inducing EMT process. However, available data on the precise molecular mechanism of Talin1 in the pathogenesis of ADS remain extremely scanty. In the present study, we aim to investigate the clinical roles of Talin1 and its effects on uterine endometrial cell migration, invasion, and EMT in ADS. Relative mRNA expression of Talin1, microRNA-145-5p (miR-145-5p), and EMT-related markers was determined by qRT-PCR. Immunohistochemistry and immunofluorescence were performed to examine the distribution of Talin1 in ADS endometrium. Protein levels of Talin1, EMT-related markers, and wnt/β-catenin pathway were measured by western blot. Wound healing assay and transwell assay were utilized for evaluating cell migration and invasion respectively. Dual-luciferase reporter assay was performed to verify the relationship between Talin1 and miR-145-5p. We found Talin1 was markedly overexpressed in ADS endometrial tissue and cells, whereas miR-145-5p was downregulated. Elevated Talin1 mRNA level might be closely related to some clinicopathological features of ADS. Through functional experiments, we demonstrated that overexpression of Talin1 induced EMT and enhanced migration and invasion ability of ADS eutopic and ectopic endometrial epithelial cells (ADS_Eu_EEC and ADS_Ec_EEC) in vitro through activating the canonical wnt/β-catenin pathway. From a mechanistic perspective, Talin1 was inversely regulated by miR-145-5p as a direct target. Our findings unveiled that under the regulation of miR-145-5p, Talin1 might promote endometrial cell migration and invasion through inducing EMT, presenting a novel insight for elucidating the pathogenesis of ADS.

Adenomyosis-derived extracellular vesicles endow endometrial epithelial cells with an invasive phenotype through epithelial-mesenchymal transition

Extracellular vesicles from highly metastatic tumor cells have been shown to mediate epithelial-mesenchymal transition (EMT)-related events in recipient cells. In endometrial epithelial cells, EMT processes are known to be involved in the development of adenomyosis. We aimed to investigate whether adenomyosis-derived extracellular vesicles (AMEVs) are able to induce an EMT process in endometrial epithelial cells. In this study, AMEVs were isolated from patients with adenomyosis and characterized by transmission electron microscopy, Western blot, and nanoparticle tracking. Primary endometrial epithelial cells (EECs) were derived from normal endometrium tissues from patients with leiomyoma and co-cultured with AMEVs in vitro. AMEV uptake was examined by fluorescence confocal microscopy. The invasion of EECs was confirmed by Transwell assay. Immunohistochemistry, Western blot, and qRT-PCR were performed on EECs to illustrate the expression levels of cytokeratin 19, E-cadherin, vimentin, and zinc finger E-box-binding homeobox 1 (ZEB1). The results indicated that the cellular fluorescence intensity gradually increased after 48 h of co-culture, but decreased after 72 h. After co-culturing with AMEVs for 72 h, EECs expressed significantly lower levels of cytokeratin 19 and E-cadherin, and significantly higher levels of vimentin and ZEB1. Together these results demonstrated that AMEVs induce an EMT process and enhance the invasion of EECs. These changes may contribute to the pathogenesis and progression of adenomyosis.

Animal Models of Adenomyosis

Adenomyosis is a nonmalignant uterine disorder in which endometrial tissue exists within and grows into the myometrium. Animal models have generated limited insight into the still-unclear pathogenesis of adenomyosis, provided a platform for preclinical screening of many drugs and compounds with potential as therapeutics, and elucidated mechanisms underlying the pain and fertility issues that occur in many women with the disease. Spontaneous adenomyosis has been studied in nonhuman primates, primarily in the form of case reports. Adenomyosis is routinely experimentally induced in mice through methods such as neonatal tamoxifen exposure, pituitary engraftment, and human tissue xenotransplantation. Several studies have also reported hormonal or environmental toxicant exposures that give rise to murine adenomyosis, and genetically engineered models have been created that recapitulate the human-like condition, most notably involving alteration of β-catenin expression. This review describes the animal models for adenomyosis and their contributions to our understanding of the factors underpinning the development of symptoms. Animal models represent a unique opportunity for understanding the molecular basis of adenomyosis and developing efficacious treatment options for affected women. Herein, we assess their different potentials and limitations with regard to identification of new therapeutic interventions and reflect on future directions for research and drug validation.

β-catenin activates TGF-β-induced epithelial-mesenchymal transition in adenomyosis

Adenomyosis is defined as the presence of ectopic nests of endometrial glands and stroma within the myometrium. Adenomyosis is a common cause of dysmenorrhea, menorrhagia, and chronic pelvic pain but is often underdiagnosed. Despite its prevalence and severity of symptoms, its pathogenesis and etiology are poorly understood. Our previous study showed that aberrant activation of β-catenin results in adenomyosis through epithelial–mesenchymal transition. Using transcriptomic and ChIP-seq analysis, we identified activation of TGF-β signaling in the uteri of mutant mice that expressed dominant stabilized β-catenin in the uterus. There was a strong positive correlation between β-catenin and TGF-β2 proteins in women with adenomyosis. Furthermore, treatment with pirfenidone, a TGF-β inhibitor, increased E-cadherin expression and reduced cell invasiveness in Ishikawa cells with nuclear β-catenin. Our results suggest that β-catenin activates TGF-β-induced epithelial–mesenchymal transition in adenomyosis. This finding describes the molecular pathogenesis of adenomyosis and the use of TGF-β as a potential therapeutic target for adenomyosis.

A regulatory link between two proteins involved in the progression of a debilitating uterine condition highlights a potential therapeutic target. Adenomyosis involves the invasion of cells from the inner lining of the uterus (the endometrium) into the uterine muscle wall (the myometrium), resulting in heavy, prolonged periods and chronic pain. The aberrent activation of a protein called β-catenin triggers adenomyosis, but the precise mechanisms are unclear. A team led by Jung-Ho Shin at the Korea University Medical Center, Seoul, South Korea, and Jae-Wook Jeong, Michigan State University, Grand Rapids, USA, used sequencing techniques in mice and human tissue samples to identify the pathways governed by β-catenin in adenomyosis. They found that the Tgf-β2 gene is directly regulated by β-catenin in the uterus. TGF-β2 levels were elevated in human adenomyosis lesions, suggesting the protein could be a therapeutic target.

Adenomyosis: Mechanisms and Pathogenesis

Adenomyosis is a common disorder of the uterus, and is associated with an enlarged uterus, heavy menstrual bleeding (HMB), pelvic pain, and infertility. It is characterized by endometrial epithelial cells and stromal fibroblasts abnormally found in the myometrium where they elicit hyperplasia and hypertrophy of surrounding smooth muscle cells. While both the mechanistic processes and the pathogenesis of adenomyosis are uncertain, several theories have been put forward addressing how this disease develops. These include intrinsic or induced (1) microtrauma of the endometrial-myometrial interface; (2) enhanced invasion of endometrium into myometrium; (3) metaplasia of stem cells in myometrium; (4) infiltration of endometrial cells in retrograde menstrual effluent into the uterine wall from the serosal side; (5) induction of adenomyotic lesions by aberrant local steroid and pituitary hormones; and (6) abnormal uterine development in response to genetic and epigenetic modifications. Dysmenorrhea, HMB, and infertility are likely results of inflammation, neurogenesis, angiogenesis, and contractile abnormalities in the endometrial and myometrial components. Elucidating mechanisms underlying the pathogenesis of adenomyosis raise possibilities to develop targeted therapies to ameliorate symptoms beyond the current agents that are largely ineffective. Herein, we address these possible etiologies and data that support underlying mechanisms.

Neonatal exposure to environment-relevant levels of tributyltin leads to uterine dysplasia in rats

Endocrine-disrupting chemicals (EDCs) are natural/synthetic compounds that mimic or inhibit the biological actions of endogenous hormones. Studies have revealed that environmental estrogen, such as bisphenol A (BPA), causes developmental defects in the uterus. Tributyltin (TBT) is a typical environmental androgen. In this study, we aimed to explore the effect and mechanism of TBT on uterine development. Neonatal female rats were exposed to TBT (10 and 100 ng/kg bw) from postnatal days 1 to 16. BPA (50 μg/kg bw) was used as a positive control. Neonatal exposure to environmental concentrations of TBT resulted in pathological changes in the uterus, including thickening of the uterine luminal epithelium, a low density of glands, endometrial inflammation and fibrosis. Further, TBT affected the Wnt signaling pathway, which might mediate developmental disorders of the endometrial epithelial cells and glands in the uterus. TBT exposure also activated the NF-κB signaling pathway, which triggered inflammation. Moreover, TBT exposure upregulated the TGF-β/Smads signaling pathway, possibly leading to endometrial fibrosis. In summary, our results demonstrate that neonatal exposure to an environment-relevant level of TBT leads to uterine dysplasia and provide potential molecular mechanisms. Our study is helpful for clarifying the effects of environmental androgens on the female reproduction system.

The Effects of Anti-TGF-β1 on Epithelial-Mesenchymal Transition in the Pathogenesis of Adenomyosis

Adenomyosis is defined as the presence of endometrial glands and stroma in the myometrium. The mechanisms associated with the pathogenesis of adenomyosis remain unclear. Epithelial-mesenchymal transition (EMT) is characterized by losing cell polarity and cell-cell adhesion together with gaining migratory and invasive properties of stromal cells to become mesenchymal stem cells. Transforming growth factor-β1 (TGF-β1), an anti-inflammatory cytokine secreted by multiple cell types, plays a crucial role in embryogenesis and tissue homeostasis. The induction of EMT and ultimate fibrosis by TGF-β1 is suggested to play a critical role in the pathogenesis of adenomyosis. Thus, this study aims to demonstrate the occurrence of EMT in and the effects of anti-TGF-β1 on the pathogenesis of adenomyosis. ICR mice were fed with 1 μg/g body weight of tamoxifen (TAM) by in the first 4 postnatal days (PNDs). Subsequently, the right and left uterine horns were correspondingly injected with or without 10 μg of anti-TGF-β1 neutralizing antibody on PND42 followed by sacrifice on PND64. E-cadherin, vimentin, and α-smooth muscle actin (α-SMA) expression in the uteri was evaluated by qRT-PCR, Western blot, and immunohistochemistry. Clusters of endometrial glands and increased numbers of vimentin-positive stromal cells in the disrupted α-SMA-positive myometrium were observed in the uteri from TAM-treated mice. Numbers of stromal cells in the myometrium and the disrupted myometrial continuity were reduced by anti-TGF-β1. Moreover, uterine expression of E-cadherin and vimentin/α-SMA was increased and decreased by anti-TGF-β1 treatment, respectively. Anti-TGF-β1 successfully inhibits EMT and the development of adenomyosis in mouse uteri.

High-Expression of Neuropilin 1 Correlates to Estrogen-Induced Epithelial-Mesenchymal Transition of Endometrial Cells in Adenomyosis

Epithelial-mesenchymal transition (EMT) induced by estrogen contributes to the development of adenomyosis. However, the exact underlying mechanism remains mostly obscure. We hypothesized that a transmembrane glycoprotein neuropilin 1 (NRP1) was critical in the EMT induced by estrogen, accelerating the development of adenomyosis. We firstly investigated the expression pattern of NRP1 in endometrium samples from women with adenomyosis. We found that NRP1 expression was significantly increased in the endometrium of uterine adenomyosis, especially in the ectopic endometrium. To determine the role of NRP1 in the EMT in endometrial cells, we used an NRP1 overexpression retrovirus to up-regulate the NPR1 expression in human endometrial cells (HEC-1-A). Endometrial cells infected with NRP1 retroviruses showed a high expression of NRP1 and exerted a mesenchymal phenotype, characterized by down-regulation of E-cadherin and Occludin, up-regulation of α-SMA and N-cadherin, and enhanced migration. Then, we found that 17β-estradiol (E2) up-regulated the expression of NRP1 in endometrial cells in a dose-dependent manner, which was eliminated by raloxifene, a selective estrogen receptor inhibitor. Importantly, NRP1 shRNA significantly suppressed the EMT induced by E2 in endometrial cells. And NRP1 shRNA significantly inhibited the phosphorylation of Smad3 and restored the expressions of Slug and Snail1 mRNA. Collectively, these data highlight the possible role of NRP1 in the EMT in the development of adenomyosis and provide a potential therapeutic target for adenomyosis patients.

NELFE promoted pancreatic cancer metastasis and the epithelial‑to‑mesenchymal transition by decreasing the stabilization of NDRG2 mRNA

Negative elongation factor E (NELFE) has been demonstrated to promote cancer progression as an RNA‑binding protein (RBP). However, the expression patterns, biological role and molecular mechanism of NELFE in pancreatic cancer (PC) remain largely unknown. The expression levels of NELFE in 120 pairs of PC tissues and adjacent non‑tumor clinical samples collected from patients with PC were examined via reverse transcription‑quantitative (RT‑q) PCR and immunohistochemistry. The mRNA expression levels of NELFE, N‑Myc downstream‑regulated gene 2 (NDRG2), c‑Myc, survivin and cyclin D1 were detected via RT‑qPCR. The protein expression levels of NELFE, NDRG2, total β‑catenin, nuclear β‑catenin, cytosolic β‑catenin, E‑cadherin, N‑cadherin and Vimentin were measured by western blotting. NELFE and NDRG2 were then knocked‑down by short hairpin (sh)RNA. PC cell proliferation was detected by MTT and colony formation assays. Invasion and migration were detected by transwell assays. The interaction between NELFE and NDRG2 was detected by luciferase reporter assays, mRNA decay assays and RNA immunoprecipitation. NELFE expression was increased in PC tissues compared with the paired non‑cancerous tissues. NELFE expression was upregulated in PC cells when compared with normal pancreatic cells (HPDE6‑C7). The present study revealed that knockdown of NELFE inhibited the proliferation, invasion and migration of PC cells. In addition, transfection of the sh‑NELFE vector inhibited the epithelial‑to‑mesenchymal transition in PC cells by suppressing the expression and nuclear accumulation of β‑catenin. Further mechanistic studies revealed that NELFE activates the Wnt/β‑catenin signaling pathway by decreasing the stabilization of NDRG2 mRNA in PC. To the best of our knowledge, these results revealed the promotional function of NELFE on PC tumorigenesis and metastasis for the first time, helping to provide a promising strategy for the treatment of patients with PC.

Biological differences between intrinsic and extrinsic adenomyosis with coexisting deep infiltrating endometriosis

RESEARCH QUESTION

Is there a biological difference between intrinsic and extrinsic adenomyosis with coexisting deep infiltrating endometriosis (DIE)?

DESIGN

In this prospective controlled study, biopsy specimens were collected after surgery from 23 women with intrinsic adenomyosis and 10 women with extrinsic adenomyosis with coexisting DIE lesions. Histological evaluation was carried out by immunoreaction to Ber-EP4 (epithelial cell marker) and CD10 (stromal cell marker). Tissue expression of oestrogen and progesterone receptors was analysed by immunohistochemistry. Tissue fibrosis was examined by Masson's trichrome staining with computer-based image analysis of fibrosis in respective samples.

RESULTS

The detection rate of coexistent DIE was significantly higher in women with extrinsic adenomyosis (9/10 [90.0%]) than in women with intrinsic adenomyosis (3/23 [13.0%]; P < 0.001). The pattern of Ber-EP4-stained glands and CD10-stained stromal cells of extrinsic adenomyosis was similar to that of coexistent DIE lesions. In contrast, the pattern of gland and stromal cells was similar to the endometrium in the cases with intrinsic adenomyosis. Unlike extrinsic adenomyosis, progesterone receptor expression was significantly decreased in both gland cells (P < 0.05) and stromal cells (P < 0.05) of intrinsic adenomyosis. Although relatively more fibrosis was seen in biopsy samples of extrinsic adenomyosis and coexistent DIE than in intrinsic adenomyosis and their coexistent DIE, no significant difference was found.

CONCLUSIONS

Extrinsic adenomyosis may be considered as adenomyosis externa based on a close histological and biological relationship between extrinsic adenomyosis and coexistent DIE. Our findings may contribute to the understanding of a possible biological origin of two newly classified intrinsic and extrinsic adenomyosis.

Secreted frizzled-related protein 2 (SFRP2) expression promotes lesion proliferation via canonical WNT signaling and indicates lesion borders in extraovarian endometriosis

STUDY QUESTION

What is the role of SFRP2 in endometriosis?

SUMMARY ANSWER

SFRP2 acts as a canonical WNT/CTNNB1 signaling agonist in endometriosis, regulating endometriosis lesion growth and indicating endometriosis lesion borders together with CTNNB1 (also known as beta catenin).

WHAT IS KNOWN ALREADY

Endometriosis is a common, chronic disease that affects women of reproductive age, causing pain and infertility, and has significant economic impact on national health systems. Despite extensive research, the pathogenesis of endometriosis is poorly understood, and targeted medical treatments are lacking. WNT signaling is dysregulated in various human diseases, but its role in extraovarian endometriosis has not been fully elucidated.

STUDY DESIGN, SIZE, DURATION

We evaluated the significance of WNT signaling, and especially secreted frizzled-related protein 2 (SFRP2), in extraovarian endometriosis, including peritoneal and deep lesions. The study design was based on a cohort of clinical samples collected by laparoscopy or curettage and questionnaire data from healthy controls and endometriosis patients.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Global gene expression analysis in human endometrium (n = 104) and endometriosis (n = 177) specimens from 47 healthy controls and 103 endometriosis patients was followed by bioinformatics and supportive qPCR analyses. Immunohistochemistry, Western blotting, primary cell culture and siRNA knockdown approaches were used to validate the findings.

MAIN RESULTS AND THE ROLE OF CHANCE

Among the 220 WNT signaling and CTNNB1 target genes analysed, 184 genes showed differential expression in extraovarian endometriosis (P < 0.05) compared with endometrium tissue, including SFRP2 and CTNNB1. Menstrual cycle-dependent regulation of WNT genes observed in the endometrium was lost in endometriosis lesions, as shown by hierarchical clustering. Immunohistochemical analysis indicated that SFRP2 and CTNNB1 are novel endometriosis lesion border markers, complementing immunostaining for the known marker CD10 (also known as MME). SFRP2 and CTNNB1 localized similarly in both the epithelium and stroma of extraovarian endometriosis tissue, and interestingly, both also indicated an additional distant lesion border, suggesting that WNT signaling is altered in the endometriosis stroma beyond the primary border indicated by the known marker CD10. SFRP2 expression was positively associated with pain symptoms experienced by patients (P < 0.05), and functional loss of SFRP2 in extraovarian endometriosis primary cell cultures resulted in decreased cell proliferation (P < 0.05) associated with reduced CTNNB1 protein expression (P = 0.05).

LIMITATIONS REASONS FOR CAUTION

SFRP2 and CTNNB1 improved extraovarian endometriosis lesion border detection in a relatively small cohort (n = 20), although larger studies with different endometriosis subtypes in variable cycle phases and under hormonal medication are required.

WIDER IMPLICATIONS OF THE FINDINGS

The highly expressed SFRP2 and CTNNB1 improve endometriosis lesion border detection, which can have clinical implications for better visualization of endometriosis lesions over CD10. Furthermore, SFRP2 acts as a canonical WNT/CTNNB1 signaling agonist in endometriosis and positively regulates endometriosis lesion growth, suggesting that the WNT pathway may be an important therapeutic target for endometriosis.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by the Academy of Finland and by Tekes: Finnish Funding Agency for Innovation. The authors have no conflict of interest to declare.

FAK regulates epithelial‑mesenchymal transition in adenomyosis

Epithelial‑mesenchymal transition (EMT) has been associated with the pathogenesis of adenomyosis; focal adhesion kinase (FAK) serves an important role in the EMT process. The aim of the present study was to determine whether FAK regulates EMT in adenomyosis and to investigate the potential pathway in this process. The expression of FAK and EMT‑associated molecules in adenomyosis and control cells were determined by immunohistochemical staining and immunofluorescence at the protein level, and at the mRNA level by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). Small interfering RNAs were designed to knock down FAK expression. Subsequently, molecular expression was detected by immunofluorescence, RT‑qPCR and western blotting; cell migration was investigated via Transwell assays. In addition, the expression levels of members of the phosphoinositide 3‑kinase (PI3K)/protein kinase B (AKT) signaling pathway was also analyzed by RT‑qPCR and western blotting to determine the association between these members and EMT in adenomyosis. The results of the present study revealed that FAK was upregulated and the expression levels of EMT‑associated molecules were altered in adenomyosis. Silencing FAK expression inhibited adenomyosis cell migration in vitro and the expression of EMT‑promoting molecules, suggesting that the FAK/PI3K/AKT signaling pathway may participate in the EMT of endometrial cells in adenomyosis. In conclusion, FAK may regulate EMT in adenomyosis, and this process may be associated with the PI3K/AKT signaling pathway.

The Possible Role of Eukaryotic Translation Initiation Factor 3 Subunit e (eIF3e) in the Epithelial-Mesenchymal Transition in Adenomyosis

Epithelial-mesenchymal transition (EMT) has been reported to be involved in adenomyosis by promoting cell invasion and fibrogenesis. But few studies have identified critical factors that regulate EMT process during adenomyosis. The eukaryotic translation initiation factor 3 subunit e (eIF3e) protein is a component of the multisubunit eIF3 complex essential for cap-dependent translation initiation. The aim of this study was to investigate whether eIF3e is involved in EMT in adenomyosis. Ectopic endometrial tissue samples were collected from 40 premenopausal women with ultrasonographically diagnosed and histologically confirmed adenomyosis. As controls, endometrial samples were obtained from 40 cycling premenopausal women patients who underwent surgery for benign gynecologic disorders or cervical intraepithelial neoplasia but without endometriosis, adenomyosis, nor uterine fibroids. All tissue samples were subjected to immunohistochemistry analysis of eIF3e, transforming growth factor-β1 (TGF-β1), E-cadherin, vimentin, Snail, and proliferating cell nuclear antigen (PCNA). The epithelial component of ectopic endometrium showed significantly reduced immunoreactivity against eIF3e and E-cadherin but elevated immunoreactivity against TGF-β1, Snail, vimentin, and PCNA as compared with that of control endometrium (all P values <.05), and the difference was not affected by age, parity, or menstrual phase. The eIF3e staining levels correlated negatively with those of TGF-β1, vimentin, Snail, and PCNA (both P values <.05). These data suggest that decreased eIF3e expression may pave way for EMT in the development of adenomyosis through activating the TGF-β1 signaling pathway. Our study provided novel insights into the development and treatments of adenomyosis.

Inhibition of DNA methyltransferase 1 by RNA interference reverses epithelial-mesenchymal transition in highly metastatic 95D lung cancer cells by inhibiting the Wnt signaling pathway

Epigenetic modifications serve important roles in non-small cell lung cancer (NSCLC) tumorigenesis; however, the role of DNA methyltransferase 1 (DNMT1) in lung cancer progression remains unclear. In the present study, the expression of DNMT1 in the human NSCLC cell lines 95D (high invasive ability) and 95C (low invasive ability) was analyzed by western blotting. The results demonstrated that the expression of DNMT1 in 95D cells was significantly higher, compared with in 95C cells and small airway epithelial cells. To further define the role of DNMT1 in tumor migration and invasion in NSCLC cells, RNA interference was used to silence DNMT1 expression. Depletion of DNMT1 significantly inhibited 95D cell invasion and migration. In addition, treatment with DNMT1 small interfering RNA resulted in compact cell morphology and significantly increased epithelial marker E-cadherin expression whilst also decreasing the expression of certain mesenchymal markers, including vimentin and fibronectin. Suppression of DNMT1 increased cytoplasmic β-catenin levels while downregulating nuclear β-catenin and Snail, an important regulator of EMT. The results from the present study suggest that the inhibition of DNMT1 reverses the epithelial-mesenchymal transition partly via the inhibition of the Wnt/β-catenin signaling pathway, and therefore inhibits cell migration and invasion. These results indicate that targeting DNMT1 may inhibit tumor metastasis and that DNMT1 is a promising target for the novel treatment of lung cancer.

Stromal Clues in Endometrial Carcinoma: Loss of Expression of β-Catenin, Epithelial-Mesenchymal Transition Regulators, and Estrogen-Progesterone Receptor

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Epithelial-stroma interactions in the endometrium are known to be responsible for physiological functions and emergence of several pathologic lesions. Periglandular stromal cells act on endometrial cells in a paracrine manner through sex hormones. In this study, we immunohistochemically evaluated the expression of epithelial-mesenchymal transition regulators (SNAIL/SLUG, TWIST, ZEB1), adhesion molecules (β-catenin and E-cadhenin), estrogen (ER)-progesterone (PR) receptor and their correlation with each other in 30 benign, 148 hyperplastic (EH), and 101 endometrioid-type endometrial carcinoma (EC) endometria. In the epithelial component, loss of expression in E-cadherin, ER and PR, and overexpression of TWIST and ZEB1 were significantly higher in EC than in EH (P<0.01). In the periglandular stromal component, β-catenin and SNAIL/SLUG expression were significantly higher in normal endometrium and simple without atypical EH compared with complex atypical EH and EC (P<0.01). In addition, periglandular stromal TWIST expression was significantly higher in EH group compared with EC (P<0.05). There was significantly negative correlation between β-catenin and ER, TWIST and ER, and TWIST and PR in hyperplastic and carcinomatous glandular epithelium, whereas there was a significantly positive correlation between β-catenin and SNAIL-SLUG, β-catenin and TWIST, β-catenin and ER, β-catenin and PR, SNAIL-SLUG and ER, SNAIL-SLUG and PR, TWIST and ER, TWIST and PR, in periglandular/cancer-associated stromal cells (P<0.01). In conclusion, the pattern of positive and negative correlations in the expression of epithelial-mesenchymal transition regulators (SNAIL-SLUG and TWIST), sex hormone receptors (ER and PR), and β-catenin between ECs and hyperplasia, as well as between epithelium and stroma herein, is suggestive of a significant role for these proteins and their underlying molecular processes in the development of endometrial carcinomas.

The long noncoding RNA FOXCUT promotes proliferation and migration by targeting FOXC1 in nasopharyngeal carcinoma

Long noncoding RNAs play an important role in various biological processes, including tumorigenesis. FOXC1 (Forkhead box C1) is a member of the Forkhead box family of transcription factors and plays a crucial role in nasopharyngeal carcinoma. In this study, a novel long noncoding RNA (FOXCUT) located upstream of FOXC1 was investigated in 42 nasopharyngeal carcinoma patients. Our analysis revealed that the expression levels of FOXCUT and FOXC1 in nasopharyngeal carcinoma tissues were significantly higher than those observed in chronic nasopharyngitis tissues and that FOXCUT expression was positively correlated with FOXC1 expression. Additionally, knockdown of FOXCUT significantly inhibited proliferation and migration of nasopharyngeal carcinoma cell lines and resulted in downregulated expression of the matrix metalloproteinase 7 and matrix metalloproteinase 9, as well as vascular endothelial growth factor A and β-catenin. Our findings suggested that FOXCUT expression contributed to the development and progression of nasopharyngeal carcinoma by targeting FOXC1 and that FOXCUT might be useful as a potential nasopharyngeal carcinoma biomarker and therapeutic target.

Lipoxin A4 Suppresses Estrogen-Induced Epithelial-Mesenchymal Transition via ALXR-Dependent Manner in Endometriosis

OBJECTIVE

Epithelial-mesenchymal transition (EMT) is essential for embryogenesis, fibrosis, and tumor metastasis. Aberrant EMT phenomenon has been reported in endometriotic tissues of patients with endometriosis (EM). In this study, we further investigated the molecular mechanism of which lipoxin A₄ (LXA₄) suppresses estrogen (E₂)-induced EMT in EM.

STUDY DESIGN

The EMT markers were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot in eutopic endometrial epithelial cells (EECs) or investigated by immunohistochemistry and qRT-PCR in endometriotic lesion of EM mice. The invasion and migration under different treatments were assessed by transwell assays with or without Matrigel. The messenger RNA (mRNA) and activities of matrix metalloproteinase 2 (MMP-2) and MMP-9 were determined by qRT-PCR and gelatin zymography, respectively. Luciferase reporter assay was used to measure the activity of zinc finger E-box binding homeobox 1(ZEB1) promoter. The level of E₂ in endometriotic tissues was assessed by enzyme-linked immunosorbent assay.

RESULTS

In eutopic EECs, stimulatory effects of E₂ on EMT progress, migration, and invasion were all diminished by LXA₄. Lipoxin A₄ reduced E₂-induced ZEB1 promoter activity. Lipoxin A₄ also attenuated the phosphorylation of extracellular signal-regulated kinase and p38 mitogen-activated protein kinase induced by E₂. Co-incubation with Boc-2 rather than DMF antagonized the influence of LXA₄. Animal experiments showed that LXA₄ inhibited the EMT progress, MMP expression, and proteinase activities of endometriotic lesion in an LXA₄ receptor (ALXR) manner, which suppressed the progression of EM. ZEB1 mRNA expression was upregulated and well correlated with E₂ level in human endometrium.

CONCLUSION

Lipoxin A₄ suppresses E₂-induced EMT via ALXR-dependent manner in eutopic EECs, which reveals a novel biological effect of LXA₄ in EM.

Epithelial-to-Mesenchymal Transition in the Female Reproductive Tract: From Normal Functioning to Disease Pathology

Epithelial-to-mesenchymal transition (EMT) is a physiological process that is vital throughout the human lifespan. In addition to contributing to the development of various tissues within the growing embryo, EMT is also responsible for wound healing and tissue regeneration later in adulthood. In this review, we highlight the importance of EMT in the development and normal functioning of the female reproductive organs (the ovaries and the uterus) and describe how dysregulation of EMT can lead to pathological conditions, such as endometriosis, adenomyosis, and carcinogenesis. We also summarize the current literature relating to EMT in the context of ovarian and endometrial carcinomas, with a particular focus on how molecular mechanisms and the tumor microenvironment can govern cancer cell plasticity, therapy resistance, and metastasis.

Differential Wnt signaling activity limits epithelial gland development to the anti-mesometrial side of the mouse uterus

In mice, implantation always occurs towards the antimesometrial side of the uterus, while the placenta develops at the mesometrial side. What determines this particular orientation of the implanting blastocyst remains unclear. Uterine glands are critical for implantation and pregnancy. In this study, we showed that uterine gland development and active Wnt signaling activity is limited to the antimesometrial side of the uterus. Dkk2, a known antagonist of Wnt signaling, is only present at the mesometrial side of the uterus. Imaging of whole uterus, thick uterine sections (100-1000µm), and individual glands revealed that uterine glands are simple tubes with branches that are directly connected to the luminal epithelium and are only present towards the antimesometrial side of the uterus. By developing a unique mouse model targeting the uterine epithelium, we demonstrated that Wnt/β-catenin signaling is essential for prepubertal gland formation and normal implantation, but dispensable for postpartum gland development and regeneration. Our results for the first time have provided a probable explanation for the antimesometrial bias for implantation.