Oestrogen-induced angiogenesis promotes adenomyosis by activating the Slug-VEGF axis in endometrial epithelial cells

Overview of crosstalk between stromal and epithelial cells in the pathogenesis of adenomyosis and shared features with deep endometriotic nodules

Since the first description of adenomyosis more than 150 years ago, multiple hypotheses have attempted to explain its pathogenesis. Indeed, research over recent years has greatly enhanced our knowledge of the underlying causes. This has opened up avenues for the development of strategies for both disease prevention and treatment of its main symptoms, such as pelvic pain, heavy menstrual bleeding, and infertility. However, the current means are still largely ineffective, so it is vital that we shed light on the pathways involved. Dysregulated mechanisms and aberrant protein expression have been identified as contributing factors in interactions between endometrial epithelial and stromal cells, ultimately leading to the growth of adenomyotic lesions. These include collective cell migration, epithelial-to-mesenchymal transition, hormonal influence, and signaling from non-coding RNAs and extracellular vesicles. We provide a concise summary of the latest insights into the crosstalk between glands and stroma in ectopic adenomyotic lesion formation. While there is an abundance of literature on similarities between adenomyosis and deep endometriosis, there are insufficient data on the cytochemical, molecular, and pathogenetic mechanisms of these two disorders. However, various shared features, including alterations of cell adhesion molecules, abnormal hormone regulation, and the presence of cancer-driving mutations and epigenetic modifications, have been identified. Nevertheless, the pathogenic mechanisms that contribute to the cause and development of these enigmatic diseases have not been fully elucidated yet.

The pathogenesis of endometriosis and adenomyosis: insights from single-cell RNA sequencing†

Endometriosis and adenomyosis are two similar gynecological diseases that are characterized by ectopic implantation and the growth of the endometrial tissue. Previous studies have reported that they share a common pathophysiology in some respects, such as a similar cellular composition and resistance to the progestogen of lesions, but their underlying mechanisms remain elusive. Emerging single-cell ribonucleic acid sequencing (scRNA-seq) technologies allow for the dissection of single-cell transcriptome mapping to reveal the etiology of diseases at the level of the individual cell. In this review, we summarized the published findings in research on scRNA-seq regarding the cellular components and molecular profiles of diverse lesions. They show that epithelial cell clusters may be the vital progenitors of endometriosis and adenomyosis. Subclusters of stromal cells, such as endometrial mesenchymal stem cells and fibroblasts, are also involved in the occurrence of endometriosis and adenomyosis, respectively. Moreover, CD8+ T cells, natural killer cells, and macrophages exhibit a deficiency in clearing the ectopic endometrial cells in the immune microenvironment of endometriosis. It seems that the immune responses are activated in adenomyosis. Understanding the immune characteristics of adenomyosis still needs further exploration. Finally, we discuss the application of findings from scRNA-seq for clinical diagnosis and treatment. This review provides fresh insights into the pathogenesis of endometriosis and adenomyosis as well as the therapeutic targets at the cellular level.

Exosomes: potential diagnostic markers and drug carriers for adenomyosis

Adenomyosis is a common benign gynecological disorder and an important factor leading to infertility in fertile women. Adenomyosis can cause deep lesions and is persistent and refractory in nature due to its tumor-like biological characteristics, such as the ability to implant, adhere, and invade. The pathogenesis of adenomyosis is currently unclear. Therefore, new therapeutic approaches are urgently required. Exosomes are nanoscale vesicles secreted by cells that carry proteins, genetic materials and other biologically active components. Exosomes play an important role in maintaining tissue homeostasis and regulating immune responses and metabolism. A growing body of work has shown that exosomes and their contents are key to the development and progression of adenomyosis. This review discusses the current research progress, future prospects and challenges in this emerging therapeutic tool by providing an overview of the changes in the adenomyosis uterine microenvironment and the biogenesis and functions of exosomes, with particular emphasis on the role of exosomes and their contents in the regulation of cell migration, proliferation, fibrosis formation, neovascularization, and inflammatory responses 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.

Maintenance dienogest therapy following adjuvant gonadotropin-releasing hormone agonist treatment after uterus-sparing surgery in adenomyosis: A retrospective cohort study

OBJECTIVE

To investigate the safety and efficacy of adjuvant gonadotropin-releasing hormone agonist (GnRH-a) treatment followed by maintenance dienogest (DNG) therapy after uterus-sparing surgery.

METHODS

Retrospective cohort study. A total of 190 patients with severe adenomyosis underwent uterus-sparing surgery between January 2010 and June 2020. Of these patients, 90 were analyzed. Forty-six patients (control group) received adjuvant 6-month GnRH-a therapy alone after uterus-sparing surgery, and 44 patients (maintenance group) received postoperative 6-month GnRH-a treatment followed by maintenance DNG therapy (2 mg/day orally). The median follow-up period was 18 months. The study was analyzed using generalized estimating equations.

RESULTS

At baseline, the characteristics of patients in each group were comparable. Compared with the control group, the maintenance group had a significant improvement in the visual analog scale score of dysmenorrhea (P < 0.001), hemoglobin level (P = 0.004), and uterine volume (P = 0.004) from baseline to 18 months after uterus-sparing surgery. The symptom recurrence rate was significantly lower in the maintenance group than in the control group (4.6% vs. 37.0%, P < 0.001).

CONCLUSIONS

The findings of this study suggest that combinatorial treatment with GnRH-a (adjuvant treatment) and DNG (maintenance therapy) represents a safe and effective short-term therapy after uterus-sparing surgery for adenomyosis.

Pre-clinical models to study abnormal uterine bleeding (AUB)

Abnormal Uterine Bleeding (AUB) is a common debilitating condition that significantly reduces quality of life of women across the reproductive age span. AUB creates significant morbidity, medical, social, and economic problems for women, their families, workplace, and health services. Despite the profoundly negative effects of AUB on public health, advancement in understanding the pathophysiology of AUB and the discovery of novel effective therapies is slow due to lack of reliable pre-clinical models. This review discusses currently available laboratory-based pre-clinical scientific models and how they are used to study AUB. Human and animal in vitro, ex vivo, and in vivo models will be described along with advantages and limitations of each method.

Uterine disorders and iron deficiency anemia

Abnormal uterine bleeding (AUB) is a clinical entity which can lead to iron deficiency anemia. Classification according to the acronym PALM-COEIN (polyp, adenomyosis, leiomyoma, malignancy, and hyperplasia; coagulopathy, ovulatory dysfunction, endometrial, iatrogenic, and not otherwise classified) provides a structured approach to establish the cause of AUB. The goal of this review is to discuss the different mechanisms and the relationship between uterine disorders and AUB. Heavy menstrual bleeding, a subgroup of AUB, is more closely related to the presence of uterine fibroids. The relationship between heavy menstrual bleeding and uterine fibroids remains poorly characterized, particularly the understanding of endometrial function in women with structural myometrial features such as leiomyomas. A number of theories have been proposed in the literature and are discussed in this review. Uterine adenomyosis is also a frequent cause of AUB, and its pathogenesis is still far from being fully elucidated. The mechanisms contributing to its development are multifactorial. Many theories lean toward invasion of the myometrium by endometrial cells. Both clinical and basic studies favor the theory of direct invasion, although de novo development of adenomyosis from Müllerian rests or stem cells has not been ruled out. Development of adenomyotic lesions involves repeated tissue injury and repair. In addition, this review describes the other causes of AUB such as endometrial polyps, cesarean scar defects, and uterine vascular abnormalities. Endometrial polyps are often asymptomatic, but approximately 68% of women have concomitant AUB. Histologic alterations in the lower uterine segment in patients who had undergone cesarean sections were identified and may explain the cause of AUB.

Mechanism Study of Cinnamomi Ramulus and Paris polyphylla Sm. Drug Pair in the Treatment of Adenomyosis by Network Pharmacology and Experimental Validation

Objective. To explore the molecular mechanism of the Cinnamomi ramulus and Paris polyphylla Sm. (C-P) drug pair in the treatment of adenomyosis (AM) based on network pharmacology and animal experiments. Methods. Via a network pharmacology strategy, a drug-component-target-disease network (D-C-T-D) and protein–protein interaction (PPI) network were constructed to explore the core components and key targets of C-P drug pair therapy for AM, and the core components and key targets were verified by molecular docking. Based on the results of network pharmacology, animal experiments were performed for further verification. The therapeutic effect of the C-P drug pair on uterine ectopic lesions was evaluated in a constructed AM rat model. Results. A total of 30 components and 45 corresponding targets of C-P in the treatment of AM were obtained through network pharmacology. In the D-C-T-D network and PPI network, 5 core components and 10 key targets were identified. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis showed that the PI3K signaling pathway was the most significantly enriched nontumor pathway. Molecular docking showed that most of the core components and key targets docked completely. Animal experiments showed that the C-P drug pair significantly ameliorated the pathological changes of endometriotic lesions in AM model rats and inhibited PI3K and Akt gene expression, and PI3K and Akt protein phosphorylation. In addition, treatment with the C-P drug pair promoted AM cell apoptosis; upregulated the protein expression of Bax, Caspase-3, and cleaved Caspase-9; and restrained Bcl-2 expression. Conclusions. We propose that the pharmacological mechanism of the C-P drug pair in the treatment of AM is related to inhibition of the PI3K/Akt pathway and promotion of apoptosis in AM ectopic lesions.

Ovarian, uterine, and luteal vascular perfusions during follicular and luteal phases in the adult cyclic female rabbits with special orientation to their histological detection of hormone receptor

Understanding the does reproductive hemodynamic changes during the estrous cycle is crucial for improving reproductive competence and fertility potential in this species. The objective of this study is to investigate the hemodynamic variations in ovarian (OA) and uterine (UA) arteries, histological and morphometric changes in ovarian and uterine tissues throughout the follicular (FP) and luteal (LP) phases in rabbits and determine estrogen (ER), progesterone (PR) receptors, and vascular endothelial growth factor (VEGF) distributions using immunohistochemistry.

Fourteen adults pluriparous New Zealand rabbits were divided into rabbits at the FP (Day − 1; n = 7) and those at the LP (Day 9; n = 7). Animals were subjected to Doppler, hormonal (estrogen [E2], progesterone [P4], insulin-like growth factor [ILGF], and VEGF), histological, and immunohistochemical analyses. In LP, OA Doppler indices were significantly increased, whereas peak systolic velocity (PSV) was decreased compared with that in FP. UA Doppler indices were significantly decreased in the LP, whereas PSV was increased (P < 0.05). E2 levels were increased in the FP, whereas P4 levels were increased in the LP. The morphometric analysis of uterine tissues during the LP revealed an increase in the mean uterine endometrium length, endometrial connective tissue area percentage (%), endometrial glands number, myometrial area (%) and thickness. Furthermore, ovarian follicles and corpus luteum (CL) displayed strong positive immunoreactivity for ER, PR, and VEGF-A during both phases. The ovarian sections displayed a substantial (P < 0.05) increase in the area % of VEGF-A in the ovarian follicles during FP while in the CL during LP. Conversely, area percentage of VEGF-A immunoreactivity in the uterine luminal and glandular epithelia during the FP and LP revealed no differences. However, the number of VEGF-A–stained blood capillaries revealed an increase during LP than FP. In conclusion, this study demonstrated for the first time the changes in both ovarian and uterine arteries during two different phases of the rabbit cycle in relation to the histo-morphometric analysis and distribution of ER, PR, and VEGF-A, which regulate uterine functions that play a role in reproduction.

Increased Angiogenesis and Lymphangiogenesis in Adenomyosis Visualized by Multiplex Immunohistochemistry

There is evidence for increased angiogenesis in the (ectopic) endometrium of adenomyosis patients under the influence of vascular endothelial growth factor (VEGF). VEGF stimulates both angiogenesis and lymph-angiogenesis. However, information on lymph vessels in the (ectopic) endometrium of adenomyosis patients is lacking. In this retrospective matched case-control study, multiplex immunohistochemistry was performed on thirty-eight paraffin embedded specimens from premenopausal women who had undergone a hysterectomy at the Amsterdam UMC between 2001 and 2018 to investigate the evidence for (lymph) angiogenesis in the (ectopic) endometrium or myometrium of patients with adenomyosis versus controls with unrelated pathologies. Baseline characteristics of both groups were comparable. In the proliferative phase, the blood and lymph vessel densities were, respectively, higher in the ectopic and eutopic endometrium of patients with adenomyosis than in the endometrium of controls. The relative number of blood vessels without α-smooth muscle actinin (α SMA) was higher in the eutopic and ectopic endometrium of adenomyosis patients versus controls. The level of VEGF staining intensity was highest in the myometrium but did not differ between patients with adenomyosis or controls. The results indicate increased angiogenesis and lymphangiogenesis in the (ectopic) endometrium affected by adenomyosis. The clinical relevance of our findings should be confirmed in prospective clinical studies.

The Menstrual Endometrium: From Physiology to Future Treatments

Abnormal uterine bleeding (AUB) is experienced by up to a third of women of reproductive age. It can cause anaemia and often results in decreased quality of life. A range of medical and surgical treatments are available but are associated with side effects and variable effectiveness. To improve the lives of those suffering from menstrual disorders, delineation of endometrial physiology is required. This allows an increased understanding of how this physiology may be disturbed, leading to uterine pathologies. In this way, more specific preventative and therapeutic strategies may be developed to personalise management of this common symptom. In this review, the impact of AUB globally is outlined, alongside the urgent clinical need for improved medical treatments. Current knowledge of endometrial physiology at menstruation is discussed, focusing on endocrine regulation of menstruation and local endometrial inflammation, tissue breakdown, hypoxia and endometrial repair. The contribution of the specialised endometrial vasculature and coagulation system during menstruation is highlighted. What is known regarding aberrations in endometrial physiology that result in AUB is discussed, with a focus on endometrial disorders (AUB-E) and adenomyosis (AUB-A). Gaps in existing knowledge and areas for future research are signposted throughout, with a focus on potential translational benefits for those experiencing abnormal uterine bleeding. Personalisation of treatment strategies for menstrual disorders is then examined, considering genetic, environmental and demographic characteristics of individuals to optimise their clinical management. Finally, an ideal model of future management of AUB is proposed. This would involve targeted diagnosis of specific endometrial aberrations in individuals, in the context of holistic medicine and with due consideration of personal circumstances and preferences.

[Adenomyosis pathophysiology: An unresolved enigma]

Adenomyosis is a chronic benign uterine disease characterized by the presence of endometrial glands and stroma within the myometrium. It is a heterogeneous disease, presenting various clinical forms, depending on the location of the ectopic lesions within the myometrium. Adenomyosis can be responsible for several symptoms such as dysmenorrhea, abnormal uterine bleeding and/or infertility. Its pathophysiology is a real conundrum and several theories have been proposed: development of adenomyosis lesion could initiate de novo from Mullerian rests or from stem cells. Moreover, multiple factors could be involved in initiating lesions, including specific hormonal, immune and/or genetic changes. The objective of this review is to provide an update on adenomyosis pathophysiology, in particular on the various theories proposed concerning the invasion of the myometrium by endometrial cells and the inducing mechanisms, and to study the link between the physiopathology, the symptoms and the medical treatments.

Uterine Adenomyosis: From Disease Pathogenesis to a New Medical Approach Using GnRH Antagonists

Uterine adenomyosis is a common chronic disorder frequently encountered in reproductive-age women, causing heavy menstrual bleeding, intense pelvic pain, and infertility. Despite its high prevalence, its etiopathogenesis is not yet fully understood, so there are currently no specific drugs to treat the disease. A number of dysregulated mechanisms are believed to contribute to adenomyosis development and symptoms, including sex steroid signaling, endometrial proliferation and invasiveness, and aberrant immune response. Abnormal sex steroid signaling, particularly hyperestrogenism and subsequent progesterone resistance, are known to play a pivotal role in its pathogenesis, which is why various antiestrogenic agents have been used to manage adenomyosis-related symptoms. Among them, gonadotropin-releasing hormone (GnRH) antagonists are swiftly gaining ground, with recent studies reporting efficient lesion regression and symptom alleviation. The aim of the present review is to compile available information on the pathogenesis of adenomyosis, explore the etiology and mechanisms of hyperestrogenism, and discuss the potential of antiestrogenic therapies for treating the disease and improving patient quality of life.

Regulatory Network Analysis in Estradiol-Treated Human Endothelial Cells

Background/Aims: Estrogen has been reported to have beneficial effects on vascular biology through direct actions on endothelium. Together with transcription factors, miRNAs are the major drivers of gene expression and signaling networks. The objective of this study was to identify a comprehensive regulatory network (miRNA–transcription factor–downstream genes) that controls the transcriptomic changes observed in endothelial cells exposed to estradiol. Methods: miRNA/mRNA interactions were assembled using our previous microarray data of human umbilical vein endothelial cells (HUVEC) treated with 17β-estradiol (E2) (1 nmol/L, 24 h). miRNA–mRNA pairings and their associated canonical pathways were determined using Ingenuity Pathway Analysis software. Transcription factors were identified among the miRNA-regulated genes. Transcription factor downstream target genes were predicted by consensus transcription factor binding sites in the promoter region of E2-regulated genes by using JASPAR and TRANSFAC tools in Enrichr software. Results: miRNA–target pairings were filtered by using differentially expressed miRNAs and mRNAs characterized by a regulatory relationship according to miRNA target prediction databases. The analysis identified 588 miRNA–target interactions between 102 miRNAs and 588 targets. Specifically, 63 upregulated miRNAs interacted with 295 downregulated targets, while 39 downregulated miRNAs were paired with 293 upregulated mRNA targets. Functional characterization of miRNA/mRNA association analysis highlighted hypoxia signaling, integrin, ephrin receptor signaling and regulation of actin-based motility by Rho among the canonical pathways regulated by E2 in HUVEC. Transcription factors and downstream genes analysis revealed eight networks, including those mediated by JUN and REPIN1, which are associated with cadherin binding and cell adhesion molecule binding pathways. Conclusion: This study identifies regulatory networks obtained by integrative microarray analysis and provides additional insights into the way estradiol could regulate endothelial function in human endothelial cells.

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.

Celecoxib reduces inflammation and angiogenesis in mice with adenomyosis

OBJECTIVE

This study aimed to explore the effect of COX-2 selective inhibitor (celecoxib) on adenomyosis and its mechanism.

METHODS

By establishing a mouse model of adenomyosis and using celecoxib to treat adenomyosis, newly born female mice were randomly divided into a control group, adenomyosis model group, and celecoxib group. Hematoxylin-eosin (H&E) staining was used to observe the depth of endometrial infiltration of mouse adenomyosis. RT-PCR (reverse transcription PCR) and western blot were used to detect the expression of Cyclooxygenase-2 (COX-2), Vascular growth factor (VEGF), Nerve growth factor (NGF), and Corticotropin-releasing hormone (CRH) mRNA and protein in mice before and after celecoxib treatment.

RESULTS

After treatment with celecoxib, the depth of endometrial infiltration of mouse adenomyosis was reduced. COX-2 and VEGF decreased significantly after celecoxib inhibited expression of COX-2 (P<0.001), but there was no significant difference in the expression of NGF or CRH (P>0.05).

CONCLUSION

This study indicated that COX-2 may be an important factor related to the pathogenesis of adenomyosis, and it may become an important molecular target for the treatment of adenomyosis.

Endometrial causes of recurrent pregnancy losses: endometriosis, adenomyosis, and chronic endometritis

Chronic inflammatory processes affecting the endometrium, as encountered in endometriosis, adenomyosis, and chronic endometritis, alter endometrial receptivity. These disorders are associated with early pregnancy losses and possibly recurrent pregnancy losses (RPL). In the cases of endometriosis, other factors associated with the disease also are susceptible of causing miscarriages and possibly RPL, such as an impact of intrapelvic inflammatory processes affecting the oocyte and embryo in case of natural conception. Conversely these latter effects obviously are bypassed in case of assisted reproductive technology. Chronic inflammation of the endometrium in the condition known as chronic endometritis also causes early pregnancy losses and RPL with beneficial effects achieved when specific treatment is undertaken.

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.

Origin and Pathogenic Mechanisms of Uterine Adenomyosis: What Is Known So Far

Uterine adenomyosis is a benign disease, commonly encountered in reproductive-age women and responsible for chronic pelvic pain, abnormal uterine bleeding, and infertility. Although the exact origin and pathogenic mechanisms involved in adenomyosis still need to be elucidated, significant progress has been made over recent years. Ever since the theory of endometrium invaginating the myometrium via a traumatized interface was first proposed, numerous molecular mechanisms have been reported to participate in this process. At the same time, an alternative theory has suggested de novo development of adenomyotic lesions from metaplasia of Müllerian remnants or adult stem cells. Hence, our understanding of the pathogenesis of adenomyosis has been greatly enhanced and is anticipated to pave the way for development of an effective and safe treatment. The goal of this review is to analyze current knowledge on the origin and pathogenic mechanisms of adenomyosis, ranging from the most widely accepted theories to newly reported data.

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.

Immunohistochemical and histophysiological study of prolonged use of nandrolone on reproductive organs and fertility

We investigated possible changes in morphology and immunohistochemistry of the uterus and ovaries of rats caused by nandrolone (ND); we also investigated effects on fertility. We used 30 rats divided into three experimental groups: control (C), control vehicle (CV) and 5 mg/kg ND. Rats treated with ND exhibited loss of estrous cyclicity with predominance of the estrus phase, increased body weight and an organosomatic index that was decreased for the ovaries, but increased for the uterus. In the ovary, we observed a reduction in primary and secondary follicles and an increase in tertiary follicles; no corpora lutea were observed. Estrogen and progesterone levels were reduced. In the uterus, the endometrium was edematous with hyperplasic glands. The cytokines, TNFα and IL6, and the apoptotic index were increased in rats treated with ND. VEGF-A was increased in the ovaries and decreased in the uterus. We conclude that ND disrupts ovarian and uterine histophysiology by establishing an anovulatory and inflammatory condition, which directly affects reproduction.

Role of angiogenesis in adenomyosis-associated abnormal uterine bleeding and subfertility: a systematic review

BACKGROUND

Adenomyosis commonly occurs with abnormal uterine bleeding (AUB) and is associated with subfertility and a higher miscarriage rate. Recent evidence showed abnormal vascularization in the endometrium in patients with adenomyosis, suggesting a role of angiogenesis in the pathophysiology of AUB and subfertility in adenomyosis and providing a possible treatment target.

OBJECTIVE AND RATIONALE

We hypothesized that the level of abnormal vascularization and expression of angiogenic markers is increased in the ectopic and eutopic endometrium of adenomyosis patients in comparison with the endometrium of control patients. This was investigated through a search of the literature.

SEARCH METHODS

A systematic search was performed in PubMed and Embase until February 2019. Combinations of terms for angiogenesis and adenomyosis were applied as well as AUB, subfertility or anti-angiogenic therapy. The main search was limited to clinical studies carried out on premenopausal women. Original research articles focusing on markers of angiogenesis in the endometrium of patients with adenomyosis were included. Studies in which no comparison was made to control patients or which were not published in a peer-reviewed journal were excluded. A second search was performed to explore the therapeutic potential of targeting angiogenesis in adenomyosis. This search also included preclinical studies.

OUTCOMES

A total of 20 articles out of 1669 hits met our selection criteria. The mean vascular density (MVD) was studied by quantification of CD31, CD34, von Willebrand Factor (vWF) or factor-VIII-antibody-stained microvessels in seven studies. All these studies reported a significantly increased MVD in ectopic endometrium, and out of the six articles that took it into account, four studies reported a significantly increased MVD in eutopic endometrium compared with control endometrium. Five articles showed a significantly higher vascular endothelial growth factor expression in ectopic endometrium and three articles in eutopic endometrium compared with control endometrium. The vascular and pro-angiogenic markers α-smooth muscle actin, endoglin, S100A13, vimentin, matrix metalloproteinases (MMPs), nuclear factor (NF)-kB, tissue factor (TF), DJ-1, phosphorylated mammalian target of rapamycin, activin A, folli- and myostatin, CD41, SLIT, roundabout 1 (ROBO1), cyclooxygenase-2, lysophosphatidic acid (LPA) 1,4-5, phospho signal transducer and activator of transcription 3 (pSTAT3), interleukin (IL)-6, IL-22 and transforming growth factor-β1 were increased in ectopic endometrium, and the markers S100A13, MMP-2 and -9, TF, follistatin, myostatin, ROBO1, LPA1 and 4-5, pSTAT3, IL-6 and IL-22 were increased in eutopic endometrium, compared with control endometrium. The anti-angiogenic markers E-cadherin, eukaryotic translation initiation factor 3 subunit and gene associated with retinoic-interferon-induced mortality 19 were decreased in ectopic endometrium and IL-10 in eutopic endometrium, compared with control endometrium. The staining level of vWF and two pro-angiogenic markers (NF-κB nuclear p65 and TF) correlated with AUB in patients with adenomyosis. We found no studies that investigated the possible relationship between markers of angiogenesis and subfertility in adenomyosis patients. Nine articles reported on direct or indirect targeting of angiogenesis in adenomyosis-either by testing hormonal therapy or herbal compounds in clinical studies or by testing angiogenesis inhibitors in preclinical studies. However, there are no clinical studies on the effectiveness of such therapy for adenomyosis-related AUB or subfertility.

WIDER IMPLICATIONS

The results are in agreement with our hypothesis that increased angiogenesis is present in the endometrium of patients with adenomyosis compared with the endometrium of control patients. It is likely that increased angiogenesis leads to fragile and more permeable vessels resulting in adenomyosis-related AUB and possibly subfertility. While this association has not sufficiently been studied yet, our results encourage future studies to investigate the exact role of angiogenesis in the etiology of adenomyosis and related AUB or subfertility in women with adenomyosis in order to design curative or preventive therapeutic strategies.

Celecoxib, a selective COX-2 inhibitor, markedly reduced the severity of tamoxifen-induced adenomyosis in a murine model

The aim of the present study was to evaluate the effects of the selective cyclooxygenase (COX)-2 inhibitor celecoxib on the development of uterine adenomyosis in mice. ICR neonatal mice were first exposed to tamoxifen to establish a mouse model of adenomyosis. Following 60 days of celecoxib treatment, pathological formation of adenomyosis lesions and the depth of myometrial infiltration were evaluated using hematoxylin and eosin staining. To examine thermal pain modulation in mice, a hotplate test was conducted every 15 days from postnatal day 30 onwards. Immunohistochemistry was performed to assess the expression of aromatase P450, N-cadherin, E-cadherin, COX-2 and cluster of differentiation 31, whereas the levels of estrogen were analyzed in uterine tissue homogenates using ELISA. Masson trichrome staining was performed to assess the extent of fibrosis in the uterus. Celecoxib treatment significantly inhibited the depth of infiltration into the myometrium, resulting in significantly reduced disease severity. Treatment with high doses of celecoxib significantly prolonged thermal response latency. Following celecoxib treatment, the expression of E-cadherin was significantly increased whereas the expression of N-cadherin was significantly decreased. Concomitantly, the extent of fibrosis was also reduced following celecoxib treatment. Uterine tissue homogenates isolated from mice treated with both high and low doses of celecoxib exhibited lower concentrations of estrogen and decreased expression of aromatase P450. These observations suggest that celecoxib reduces adenomyosis severity by suppressing estrogen production in the uterus, reversing epithelial-mesenchymal transition and relieving fibrosis. Taken together, the results of the present study support the potential use of celecoxib, a selective COX-2 inhibitor, for the treatment of adenomyosis.

Effect of ovarian steroids on vascular endothelial growth factor a expression in bovine uterine endothelial cells during adenomyosis

Background

Adenomyosis is a uterine dysfunction defined as the presence of endometrial glands within the myometrium. There is evidence that proangiogenic factors may play a role during the development of adenomyosis; however, exact mechanism remains unknown. The aim of the study was to determine the action of vascular endothelial growth factor A (VEGFA) in uterine tissue and uterine vascular endothelial cells during adenomyosis.

Results

Uterine tissues were collected and examined for the presence and extent of adenomyosis. Gene and protein expression of VEGFA and its two receptors (VEGFR1 and VEGFR2) was evaluated with quantitative polymerase chain reaction and Western blotting, respectively, in endometrium and myometrium during adenomyosis. Immunolocalization of VEGFA and its receptors within uterine tissues during adenomyosis was also determined. In an in vitro experiment, endothelial cells from non-adenomyotic bovine uteri were treated with media conditioned by non-adenomyotic or adenomyotic uterine slices treated with 17-beta-oestradiol (E2) or progesterone (P4). Both gene and protein expression of VEGFR2 were elevated in endometrium in stages 3–4 of adenomyosis. Protein expression of VEGFA and VEGFR2 as well as VEGFA secretion were increased in endothelial cells treated with media conditioned by adenomyotic uterine slices after E2 treatment.

Conclusions

Results suggest that VEGFA signalling is an important component, next to E2, that enhances VEGFA action and participates in adenomyosis development in cows.

E2 -mediated EMT by activation of β-catenin/Snail signalling during the development of ovarian endometriosis

Endometriosis is an oestrogen-dependent disease, and epithelial-mesenchymal transition (EMT) is involved in the process of endometriosis. Whether oestrogen could induce EMT in endometriosis remains largely unknown. Here, we reported that up-regulated expression of EMT markers in ovarian chocolate cyst is accompanied by high expression 17β-hydroxysteroid dehydrogenase 1 (17β-HSD1), and exposure of primary human endometrial epithelial cells to oestradiol conditions could promote EMT occurrence and activate both β-catenin and Snail signalling. Furthermore, we found nuclear β-catenin and Snail expression was closely linked in ovarian endometriosis, and β-catenin knockdown abrogated oestrogen-induced Snail mediated EMT in vitro. This is due to that β-catenin/ TCF-3 could bind to Snail promoter and activate its transcription. These results suggested that β-catenin signalling functions as the Snail activator and plays a critical role in oestradiol-induced EMT in endometriosis.

Endothelial-to-Mesenchymal Transition (EndoMT): Roles in Tumorigenesis, Metastatic Extravasation and Therapy Resistance

Cancer cells evolve in a very complex tumor microenvironment, composed of several cell types, among which the endothelial cells are the major actors of the tumor angiogenesis. Today, these cells are also characterized for their plasticity, as endothelial cells have demonstrated their potential to modify their phenotype to differentiate into mesenchymal cells through the endothelial-to-mesenchymal transition (EndoMT). This cellular plasticity is mediated by various stimuli including transforming growth factor-β (TGF-β) and is modulated dependently of experimental conditions. Recently, emerging evidences have shown that EndoMT is involved in the development and dissemination of cancer and also in cancer cell to escape from therapeutic treatment. In this review, we summarize current updates on EndoMT and its main induction pathways. In addition, we discuss the role of EndoMT in tumorigenesis, metastasis, and its potential implication in cancer therapy resistance.

Oestrogen Inhibits VEGF Expression And Angiogenesis In Triple-Negative Breast Cancer By Activating GPER-1

Triple-negative breast cancer (TNBC) is the most malignant type of breast cancer with ample vascularisation and high vascular endothelial growth factor (VEGF) expression. The sex steroid hormone oestrogen is involved in several cellular activities associated with TNBC regulation. However, the role of oestrogen in VEGF expression and angiogenesis in TNBC remains unclear. In this study, we found that treatment with 17β-oestradiol (E2) inhibited VEGF mRNA and protein expression in the TNBC cell lines MDA-MB-468 and MDA-MB-436. To further elaborate on the phenomenon of E2-regulated angiogenesis, we showed that conditioned medium from the TNBC cell line MDA-MB-468 treated with E2 inhibits the tube formation ability of human umbilical vein endothelial cells (HUVECs). Additionally, the G-protein-coupled oestrogen receptor-1 (GPER-1)-specific agonist G-1 has a function similar to that of E2. While G-15, the selective antagonist of GPER-1, notably reversed the inhibitory effects of E2 and G-1 on VEGF expression and tube formation, suggesting that GPER-1 is involved in the E2-induced angiogenesis suppression in TNBC cells. Moreover, E2 inhibited in vivo tumour growth and angiogenesis and reduced the expression levels of VEGF, NF-κB/p65, STAT3, and the endothelial marker CD34 in MDA-MB-468 xenograft tumours. Our findings provide important evidence that E2 can inhibit VEGF expression and angiogenesis in TNBC by activating GPER-1, offering additional insight into tumour angiogenesis and targets for drug intervention in TNBC.

Inside the Endometrial Cell Signaling Subway: Mind the Gap(s)

Endometrial cells perceive and respond to their microenvironment forming the basis of endometrial homeostasis. Errors in endometrial cell signaling are responsible for a wide spectrum of endometrial pathologies ranging from infertility to cancer. Intensive research over the years has been decoding the sophisticated molecular means by which endometrial cells communicate to each other and with the embryo. The objective of this review is to provide the scientific community with the first overview of key endometrial cell signaling pathways operating throughout the menstrual cycle. On this basis, a comprehensive and critical assessment of the literature was performed to provide the tools for the authorship of this narrative review summarizing the pivotal components and signaling cascades operating during seven endometrial cell fate “routes”: proliferation, decidualization, implantation, migration, breakdown, regeneration, and angiogenesis. Albeit schematically presented as separate transit routes in a subway network and narrated in a distinct fashion, the majority of the time these routes overlap or occur simultaneously within endometrial cells. This review facilitates identification of novel trajectories of research in endometrial cellular communication and signaling. The meticulous study of endometrial signaling pathways potentiates both the discovery of novel therapeutic targets to tackle disease and vanguard fertility approaches.

Dehydroepiandrosterone supplementation is not beneficial in the late postmenopausal period in diet-induced obese rats

AIMS

Dehydroepiandrosterone (DHEA) is an adrenal steroid hormone that is a precursor of sexual hormones. It is reduced during aging and is strongly associated with insulin resistance and obesity. There is evidence for beneficial effects of this steroid, in both human and animal models, during perimenopause. However, the impact of DHEA treatment during late postmenopause on glucose metabolism is not clearly documented. We tested the hypothesis that DHEA supplementation could improve insulin sensitivity in an ovariectomized obese rat model (OVX) that was fed a high-fat diet for 11 weeks.

MAIN METHODS

Female Wistar rats at 8 weeks of age were OVX or SHAM-operated. Eight weeks after the surgery, the animals were randomly treated with vehicle or DHEA for 3 weeks. Food intake, metabolic parameters and insulin sensitivity were evaluated.

KEY FINDINGS

Following the ovariectomy, increased body weight gain, adiposity index, and feeding efficiency were observed, despite there being no change in food and energy intake. The OVX rats also displayed glucose intolerance, insulin resistance, decreased insulin-induced IRS1/2 tyrosine phosphorylation in the skeletal muscle, and reduced serum VLDL-c and TAG levels. OVX rats treated with 10 mg/kg DHEA (OVX + DHEA) exhibited estradiol (E₂) serum levels similar to SHAM animals, with no change in uterus mass. DHEA treatment also resulted in an increase in energy intake.

SIGNIFICANCE

Despite the positive effects of DHEA supplementation observed in menopausal women and ovariectomized rats, a potential negative effect on glucose metabolism and insulin action in the late postmenopausal condition in diet-induced obese OVX rats are reported.

Basic mechanisms of vascularization in endometriosis and their clinical implications

BACKGROUND

Vascularization is a major hallmark in the pathogenesis of endometriosis. An increasing number of studies suggests that multiple mechanisms contribute to the vascularization of endometriotic lesions, including angiogenesis, vasculogenesis and inosculation.

OBJECTIVE AND RATIONALE

In this review, we provide an overview of the basic mechanisms of vascularization in endometriosis and give special emphasis on their future clinical implications in the diagnosis and therapy of the disease.

SEARCH METHODS

Literature searches were performed in PubMed for English articles with the key words 'endometriosis', 'endometriotic lesions', 'angiogenesis', 'vascularization', 'vasculogenesis', 'endothelial progenitor cells' and 'inosculation'. The searches included both animal and human studies. No restriction was set for the publication date.

OUTCOMES

The engraftment of endometriotic lesions is typically associated with angiogenesis, i.e. the formation of new blood vessels from pre-existing ones. This angiogenic process underlies the complex regulation by angiogenic growth factors and hormones, which activate intracellular pathways and associated signaling molecules. In addition, circulating endothelial progenitor cells (EPCs) are mobilized from the bone marrow and recruited into endometriotic lesions, where they are incorporated into the endothelium of newly developing microvessels, referred to as vasculogenesis. Finally, preformed microvessels in shed endometrial fragments inosculate with the surrounding host microvasculature, resulting in a rapid blood supply to the ectopic tissue. These vascularization modes offer different possibilities for the establishment of novel diagnostic and therapeutic approaches. Angiogenic growth factors and EPCs may serve as biomarkers for the diagnosis and classification of endometriosis. Blood vessel formation and mature microvessels in endometriotic lesions may be targeted by means of anti-angiogenic compounds and vascular-disrupting agents.

WIDER IMPLICATIONS

The establishment of vascularization-based approaches in the management of endometriosis still represents a major challenge. For diagnostic purposes, reliable angiogenic and vasculogenic biomarker panels exhibiting a high sensitivity and specificity must be identified. For therapeutic purposes, novel compounds selectively targeting the vascularization of endometriotic lesions without inducing severe side effects are required. Recent progress in the field of endometriosis research indicates that these goals may be achieved in the near future.

A formulation of pancreatic pro-enzymes provides potent anti-tumour efficacy: a pilot study focused on pancreatic and ovarian cancer

Proteolytic enzymes have shown efficacy in cancer therapy. We present a combination of the two pro-enzymes Trypsinogen and Chymotrypsinogen A with potent in vitro and in vivo anti-tumour efficacy. A synergetic anti-tumour effect for Trypsinogen and Chymotrypsinogen A was determined at a ratio 1:6 (named PRP) using 24 human cancer cell lines. The antiangiogenic effect of PRP was analysed by matrigel-based tube formation and by fibrous capsule formation assays. Furthermore, cell invasion and wound healing assays together with qRT-PCR determination of epithelial-to-mesenchymal transition (EMT) markers were performed on human cancer cells treated with PRP. Additionally, in vivo pharmacokinetic studies were implemented and the PRP's anti-tumour efficacy was explored against orthotopic pancreatic and ovarian cancer tumours. PRP formulation was proven to inhibit in vitro angiogenesis, tumour growth, cancer cell migration and invasiveness; and to be an effective and well tolerated in vivo anti-tumour treatment. Finally, the clinical efficacy of a suppository formulation containing both pancreatic pro-enzymes in the context of a UK Pharmaceuticals Special Scheme was evaluated in advanced cancer patients. Consequently, PRP could have relevant oncological clinical applications for the treatment of advanced or metastatic pancreatic adenocarcinoma and advanced epithelial ovarian cancer.

Response to comment on "Oestrogen-induced angiogenesis and implantation contribute to the development of parasitic myomas after laparoscopic morcellation"

According to the literature review, CO2 insufflation on parasitic myoma implantation is not well studied, and we concur that our study is related to "Morcellation-induced parasitic myomas." We did not compare CO2 insufflation to non-insufflation in our study. The reason is the efficacy of gasless laparoscopic myomectomy and morcellation is not well established and this modality is seldom performed. Moreover, the effects of pneumoperitoneum on mesothelial cells and the role of the entire peritoneal cavity as a cofactor in adhesion formation have become well established, the role of CO2 insufflation in the establishment of parasitic myomas has not yet been studied. As such, more in-depth and well-designed studies for the role of CO2 insufflation are needed.

The zinc-finger transcriptional factor Slug transcriptionally downregulates ERα by recruiting lysine-specific demethylase 1 in human breast cancer

Estrogen receptor α (ERα) is related with epithelial-mesenchymal transition, invasion and metastasis, and serves as an important therapeutic predictor and prognostic factor in breast cancer patients. The triple negative breast cancer (TNBC) is characterized by loss of hormone receptors and human epidermal growth factor receptor 2 (Her2), and lacks effective targeted therapy with poor prognosis. Unfortunately, the molecular mechanisms of ERα deficiency, which becomes hormone independent and results in resistance to endocrine therapy, remain to be elucidated in breast cancer. In this study, we observed an inverse correlation between Slug, a zinc-finger transcriptional repressor, and ERα expression in both human breast cancer tissues and cell lines. In ERα-negative breast cancer patients, high Slug messenger RNA expression showed obviously shorter relapse-free survival. We found that Slug binds to the E-box located in the promoter of estrogen receptor 1 gene (ESR1) to suppress its expression. More specifically, Slug recruits lysine-specific demethylase 1 (LSD1) to the E-box and thereby inhibits ERα expression by demethylating H3K4me2, which is evidenced by the interaction between Slug and LSD1. Moreover, the amount of H3K4me2 binding to the E-box was significantly increased after LSD1 knockdown in MDA-MB-231 cells. Functionally, the ability to proliferate, invade and metastasize was significantly suppressed after knockdown of either Slug or LSD1 alone, or both simultaneously. Taken together, these results suggest that Slug transcriptionally inhibits ERα expression by recruiting LSD1 to the ESR1 promoter in breast cancers. Thus, targeted inhibition of Slug and LSD1 may restore ERα and lead to resensitization to hormone therapy, providing a novel therapeutic strategy for ERα-negative breast cancer patients, especially for TNBC.

Expression and regulation of Angiopoietins and their receptor Tie-2 in sika deer antler

The cartilage vascularization and chondrocyte survival are essential for endochondral ossification which occurs in the process of antler growth. Angiopoietins (Ang) is a family of major angiogenic growth factors and involved in regulating the vascularization. However, the expression and regulation of Angs in the antler are still unknown. The aim of this study is to localize the expression of Ang-1, Ang-2 and their receptor Tie-2 in sika deer antler using in situ hybridization and focused on analyzing the regulation of testosterone, estrogen, all-trans-retinoic acid (ATRA) and 9cRA on their expression in antler chondrocytes. The results showed that Ang-1, Ang-2 and Tie-2 were highly expressed in antler chondrocytes. Administration of testosterone to antler chondrocytes led to a notable increase in the expression of Ang-1 and Tie-2, and a reduction in the expression of Ang-2. The similar result was also observed after estrogen treatment. In contrast, ATRA and 9cRA could inhibit the expression of Ang-1 in antler chondrocytes and heighten the expression of Ang-2. Simultaneously, ATRA could downregulate the expression of Tie-2 in antler chondrocytes at 12 and 24 h, while 9cRA upregulate the expression of Tie-2 at 3 and 6 h. Collectively, Ang-1, Ang-2 and Tie-2 are expressed in antler chondrocytes and their expression can be affected by testosterone, estrogen, ATRA and 9cRA.

Prolactin role in the bovine uterus during adenomyosis

Adenomyosis is uterine dysfunction defined as the presence of endometrial glands within the myometrium. It is suggested that adenomyosis is estrogen-dependent pathology, and prolactin (PRL) also affects its development. In the uterus of ruminants, PRL stimulates gland proliferation and function. We hypothesized that in the bovine uterus, the expression of PRL and its receptors (PRLRs) during adenomyosis is disturbed and modulated by estradiol (E₂). Uterine tissues were collected postmortem from cows; epithelial, stromal, and myometrial cells were isolated; and cultured and treated with E₂. Material was divided into 2 groups: control (nonadenomyotic) and uteri with adenomyosis. In adenomyotic uterine tissue, PRL and its long-form receptor protein were increased, as determined by Western blotting. Immunohistostaining showed that during adenomyosis, PRL and its receptors are highly expressed in adenomyotic lesions. In cultured myometrial cells, protein expression of PRL and its receptors was increased during adenomyosis. Estradiol decreased PRLRs protein expression in nonadenomyotic stromal cells and in adenomyotic myometrial cells, and increased PRL secretion by adenomyotic myometrial cells. Moreover, PRL secretion was increased in untreated epithelial and stromal cells during adenomyosis. On the other hand, in stromal cells, PRLRs messenger RNA and protein expression was decreased, as determined by real-time PCR and Western blotting, respectively. Obtained results show that significant changes in PRL and PRLRs expression are observed in uterine tissue and cells during adenomyosis, which were also affected by E₂. These data suggest involvement of PRL in adenomyosis development and the link between PRL and E₂ actions during the dysfunction in cows.

Current and Future Medical Treatment of Adenomyosis

Adenomyosis is a benign gynecological disorder associated with abnormal uterine bleeding, dysmenorrhea, dyspareunia and infertility, requiring a life-long management plan through medical or surgical treatment. The choice depends on woman's age, reproductive status and clinical symptoms. However, until now no drug labelled for adenomyosis is available; thus, the present review will focus on medical treatments currently used for adenomyosis and those in development.

Adenomyosis may be considered a sex steroid hormone-related disorder associated with an intense inflammatory process. The use of gonadotropin-releasing hormone agonists (GnRH-a) for treating adenomyosis is described blocking the hypothalamic-pituitary-gonadal axis; however, it has long been associated with frequent and intolerable hypoestrogenic side effects. An antiproliferative effect of progestins suggests their use for treating adenomyosis, reducing bleeding and pain. Continuous oral norethisterone acetate or medroxyprogesterone acetate may help to inducing regression of adenomyosis, relief pain and reduce bleeding. The use of vaginal danazol has therapeutic effect on adenomyosis combining progestogenic and anti-inflammatory activity. The intrauterine device releasing levonorgestrel (Lng-IUD) is widely assessed in menorrhagia, and has been shown to be extremely effective in resolving pain and bleeding symptoms associated with adenomyosis. Recent data show a therapeutic effect of dienogest on adenomyosis symptoms.

New drugs are under development for the treatment of adenomyosis, such as aromatase inhibitors (AIs) and selective estrogen receptor modulators (SERMs), that produce a hypoestrogenic environment reducing pain, but are correlated with some adverse effects and a recurrence of symptoms after discontinuation of treatment. Selective progesterone receptor modulators (SPRMs) may reduce adenomyosis-associated pelvic pain, by inhibiting endometrial proliferation and suppressing adenomyotic lesion growth, as shown in animal models; however, the long-term effect with SPRMs needs further determination.

Oestrogen-induced angiogenesis and implantation contribute to the development of parasitic myomas after laparoscopic morcellation

BACKGROUND

Iatrogenic parasitic myomas (PMs), caused by intra-corporeal power morcellation during laparoscopy is gradually increasing. However, the pathogenesis and medical treatment of PMs remain largely unelucidated.

METHODS

Laparoscopically-induced PM xenografted mouse model was conducted by xenografting human uterine myoma fragments into the abdominal cavity of SCID mice and hormonal manipulation was performed using this mouse model to demonstrate the role of oestrogen in the development of implanted PMs. Immunohistochemistry of oestrogen receptor α (ERα), progesterone receptor (PR), vimentin, vascular endothelial growth factor (VEGF), microvessel density (MVD) and Ki-67 index was performed and compared.

RESULTS

In the patient with PMs, ERα, PR, angiogenesis and proliferative property expression were upregulated in PM lesions compared to uterine myomas. In the laparoscopically-induced PM mouse model, implanted myomas had more steroid receptor expressions, angiogenesis and proliferative property compared with pre-xenografted or non-implanted myoma. Depletion of oestrogen in the ovariectomized (OVX) mice decreased laparoscopically-induced PM implantations. In comparison, the implantations of PMs were increased with additional E2 supplement. Hormonal manipulation in the PM mouse model, including AI, GnRHa and SERM groups, were compared and AI significantly decreased the implantations, steroid receptor, angiogenesis, cell density, and proliferative index of PMs compared with control group. Furthermore, GnRHa significantly decreased VEGF and MVD expressions compared with control group.

CONCLUSIONS

These data highlight the crucial role of oestrogen in the development of laparoscopically-induced PMs and suggest that hormone manipulation may be a potential therapeutic agent.

TRIAL REGISTRATION

This protocol was approved by the Human and Animal Institutional Review Board of Taipei Veterans General Hospital ( VGHIRB No 2014-10-002C on Nov. 17^th, 2014; IACUC 2014-119 on Aug. 22^nd, 2014).

Proangiogenic features in chronic pelvic pain caused by adenomyosis

AIM

The study of peculiarities of expression of vascular endothelial growth factor (VEGF) in the tissues of the endometrium and myometrium in patients with adenomyosis, associated with chronic pelvic pain syndrome.

MATERIALS AND METHODS

Uterus macro-preparations obtained after hysterectomy in 60 patients with pelvic pain on a background of diffuse adenomyosis II-III degree were used for morphological examination, and macro-preparations received from 30 women with adenomyosis without pain syndrome. The diagnosis of adenomyosis was confirmed by sonography and magnetic resonance imaging. The expression of VEGF in tissues of the endometrium and myometrium was determined using the immune-histochemical method. The significance of differences of the compared parameters was determined using the criterion of Wilcoxon and Mann-Whitney. The differences were considered statistically significant when p < 0.05.

RESULTS

It was found that a higher expression of VEGF is characteristic for patients with pelvic pain associated with adenomyosis, compared to women with adenomyosis and abnormal uterine bleeding, both in epithelial cells of ectopic endometrium (14.7 ± 1.6% against 10.7 ± 1.6%, p < 0.01), and in smooth myocytes of the myometrium (12.6 ± 1.4% against 9.6 ± 1.2%, p < 0.01) and in the stromal cells of the myometrium (10.1 ± 1.9% versus 7.4 ± 1.8%, p < 0.01).

CONCLUSIONS

An increased expression of VEGF in the tissues of the uterus is one of the most important pathogenetic mechanisms of algogenesis with adenomyosis, associated syndrome of chronic pelvic pain, compared to the silent form of the disease.

Global Transcriptome Abnormalities of the Eutopic Endometrium From Women With Adenomyosis

OBJECTIVE

Adenomyosis is a clinical disorder defined by the presence of endometrial glands and stroma within the myometrium, the pathogenesis of which is poorly understood. We postulate that dysregulation of genes and pathways in eutopic endometrium may predispose to ectopic implantation. No study, to our knowledge, has examined the global transcriptome of isolated eutopic endometrium from women with clinically significant adenomyosis.

DESIGN

Laboratory-based study with full institutional review board approval and consents.

MATERIAL AND METHODS

Endometrial sampling was performed on hysterectomy specimens (proliferative phase) from symptomatic women with pathologically confirmed diffuse adenomyosis (n = 3). Controls (n = 5) were normo-ovulatory patients without adenomyosis. All patients were free from leiomyoma, endometriosis, and hormonal exposures. Isolated purified total RNA was subjected to microarray analysis using the Gene 1.0 ST Affymetrix platform. Data were analyzed with GeneSpring and Ingenuity Pathway analysis. Validation of several genes was undertaken by quantitative real-time reverse transcriptase polymerase chain reaction.

RESULTS

Comparison of transcriptomes of proliferative endometrium from women with and without adenomyosis revealed 140 upregulated and 884 downregulated genes in samples from women with adenomyosis compared to controls. Highly differentially expressed genes include those involved in regulation of apoptosis, steroid hormone responsiveness, and proteins involved in extracellular matrix remodeling as well as microRNAs of unknown significance. Affected canonical pathways included eukaryotic initiation factor 2 signaling, oxidative phosphorylation, mitochondrial dysfunction, estrogen receptor signaling, and mammalian target of rapamycin signaling.

CONCLUSION

The eutopic endometrium in patients with adenomyosis has fundamental abnormalities that may predispose to invasion and survival beyond the myometrial interface.

Involvement of NADPH oxidase and NF-κB activation in CXCL1 induction by vascular endothelial growth factor in human endometrial epithelial cells of patients with adenomyosis

Chemokines were known to participate in inflammation and angiogenesis but have been recently recognized to be involved in embryonic implantation and endometrium-related pathologies. Among these chemokines, the CXC chemokines, such as CXCL1, have potential roles to work as biomarkers to identify patients with uterine adenomyosis. In this study, human endometrial epithelial cells (HEECs) were derived from patients' endometrium with adenomyosis. The inductive effects of CXCL1 production by various mediators/growth factors were investigated in the HEECs. Of the tested mediators, VEGF was found to be the most effective. The immunohistochemistry and RT-PCR analysis revealed a positive staining for VEGF and CXCL1 at the epithelium and the presence of CXCL1 in the human endometrium specimens, respectively. The CXCL1 induction by VEGF could be reduced by the antagonist for VEGF receptor (VEGFR), and by the inhibitors for NADPH oxidase and NF-κB signaling pathway. However, it was not affected by sex hormones and the inhibitors for MAPKs, PI-3K, protein kinase A and C. In parallel, VEGF induced p47 phox NADPH oxidase activation, IκBα phosphorylation, NF-κB translocation and NF-κB-DNA complex formation in the HEECs. Moreover, the CXCL1 released by the HEECs with VEGF stimulation attracted vascular endothelial cell migration. Taken together, we show that VEGF and CXCL1 are expressed in epithelium of the endometrium with adenomyosis and demonstrate here for the first time that VEGF is capable of inducing CXCL1 expression in HEECs through VEGFR, p47 phox NADPH oxidase and NF-κB signaling pathway, which is functionally required for attracting vascular endothelial cell migration.

Increased expression of nuclear factor kappa-B p65 subunit in adenomyosis

Objective

Nuclear factor kappa-B (NF-κB) is a critical proinflammatory regulator that has been suggested to play a pivotal role in the pathogenesis and pathophysiology of endometriosis. In the present study, we aimed to evaluate whether the expression of NF-κB p65 subunit is increased in the eutopic endometrium and/or in the adenomyosis nodule of women with adenomyosis.

Methods

Thirty-three women with histologically confirmed adenomyosis after laparoscopic or transabdominal hysterectomy were recruited. Women with carcinoma in situ of uterine cervix without evidence of adenomyosis or endometriosis (n=32) served as controls. Formalin-fixed, paraffin-embedded archival tissues were sectioned and immunostained utilizing a monoclonal anti-human NF-κB p65 subunit antibody, and the immunoreactivity of NF-κB p65 subunit was compared between women with and without adenomyosis.

Results

The immunoreactivities of both the nuclear and the cytoplasmic NF-κB p65 subunit were significantly increased in the stromal cells in the eutopic endometrium as well as in the adenomyosis nodule of women with adenomyosis compared with controls, respectively. The nuclear expression of NF-κB p65 subunit was significantly higher in the glandular cells in the eutopic endometrium as well as the adenomyosis nodule of women with adenomyosis compared with controls, respectively.

Conclusion

The expression of NF-κB p65 is increased in the eutopic endometrium and adenomyosis nodule of women with adenomyosis, which strongly suggest that NF-κB plays a critical role in the pathogenesis and/or pathophysiology of adenomyosis.

Expression of GRIM-19 in adenomyosis and its possible role in pathogenesis

OBJECTIVE

To study the expression of the gene associated with retinoid-interferon (IFN)-induced mortality 19 (GRIM-19) in the endometrial tissue of patients with adenomyosis and to describe the possible pathogenic mechanisms of this phenomenon.

DESIGN

Experimental study using human samples and cell lines.

SETTING

University-affiliated hospital.

PATIENT(S)

Ectopic and eutopic endometrial tissues were obtained from 30 patients with adenomyosis, whereas normal endometrial specimens were obtained from 10 control patients without adenomyosis.

INTERVENTION(S)

Patients with rapid pathology report-confirmed adenomyosis were recruited, and eutopic and ectopic endometrial tissue samples were collected from patients who had undergone hysterectomies by either the transabdominal or laparoscopic method at Qilu Hospital. Normal endometrial tissue was collected from a group of control patients without adenomyosis.

MAIN OUTCOME MEASURE(S)

Immunohistochemistry (IHC) was performed to evaluate the expression of GRIM-19, phospho-signal transducer and activator of transcription 3 (Y705) (Y705) (pSTAT3(Y705)), and vascular endothelial growth factor (VEGF) in endometrial tissue samples. The protein levels of GRIM-19, pSTAT3(Y705), STAT3, and VEGF were detected by Western blot. Apoptosis in endometrial specimens was assayed by TUNEL. Immunohistochemistry with an antibody directed against CD34 was performed to detect new blood vessels in the endometrial tissue. GRIM-19 small interfering RNA and a recombinant plasmid carrying GRIM-19 were constructed to evaluate the effects of GRIM-19 on the downstream factors pSTAT3(Y705), STAT3, and VEGF in Ishikawa cells.

RESULT(S)

The expression of GRIM-19 was down-regulated in the eutopic endometria of patients with adenomyosis compared with the endometria of patients in the control group, and it was further reduced in the endometrial glandular epithelial cells of adenomyotic lesions. Apoptosis was reduced in the eutopic endometrium compared with the control group, and it was significantly reduced in ectopic endometrial tissues. In addition, the ectopic and eutopic endometria of patients with adenomyosis displayed a much higher microvessel density. In the eutopic and ectopic endometria of patients with adenomyosis, the expression levels of pSTAT3(Y705) and VEGF were significantly higher than in the controls. Furthermore, down-regulation of GRIM-19 in Ishikawa cells significantly promoted the activation of both pSTAT3(Y705) and its dependent gene VEGF.

CONCLUSION(S)

Aberrant expression of GRIM-19 may be associated with adenomyosis through the regulation of apoptosis and angiogenesis.