Association between Uterine Adenomyosis and Infertility: Role of Axonemal Alteration in Apical Endometria.

ABSTRACT: Uterine adenomyosis is an estrogen-dependent chronic inflammatory condition and may cause painful symptoms, abnormal uterine bleeding, and/or subfertility/infertility. It is characterized by the presence of endometrial glands and stroma within the myometrium causing enlargement of the uterus as a result of reactive hyperplastic and/or hypertrophic change of the surrounding myometrium. Similar to endometriosis, adenomyosis has a negative impact on female fertility. Abnormal uterotubal sperm transport, tissue inflammation, and the toxic effect of chemical mediators have been proposed as contributing factors. Inflammation-induced damage of the mucosal cilia in the fallopian tube has been reported. Besides other proposed mechanisms, our most recent study with transmission electron microscopy analysis indicated that microvilli damage and an axonemal alteration in the apical endometria occur in response to endometrial inflammation. This may be involved in the negative fertility outcome in women with adenomyosis. We present a critical analysis of the literature data concerning the mechanistic basis of infertility in women with adenomyosis and its impact on fertility outcome.

Transforming growth factor beta-1 (TGF-ß1) expression in patients with adenomyosis.

Objective: To compare Transforming growth factor beta-1 (TGF-ß1) expression in patients with and without adenomyosis. Methods: A prospective design was performed including 49 patients submitted to hysterectomy. Immunohistochemistry was performed on anatomopathological samples staged in paraffin blocks from patients with and without adenomyosis. The sample contained 28 adenomyosis cases and 21 controls. Student's t-test and multivariate logistic regression tests were used for statistical analysis. Associations were considered significant at p < 0.05. Results: We found no significant association between adenomyosis and: smoking (p = 0.75), miscarriage (p = 0.29), number of previous pregnancies (p = 0.85), curettage (p = 0.81), pelvic pain (p = 0.72) and myoma (p = 0.15). However, we did find a relationship between adenomyosis and abnormal uterine bleeding (AUB) (p = 0.02) and previous cesarean section (p = 0.02). The mean TGF-ß1 intensity (mean ± SD) in the ectopic endometrium of women with adenomyosis showed no significant association (184.17 ± 9.4 vs.184.66 ± 16.08, p = 0.86) from the topic endometrium of women without adenomyosis. Conclusion: TGF-ß1 expression was not increased in the ectopic endometrium of women with adenomyosis.

[Estrogen, estrogen receptor and miR-21 in adenomyosis: their pathogenic roles and regulatory interactions].

OBJECTIVE: To explore the pathogenic roles of miR-21, estrogen (E2), and estrogen receptor (ER) in adenomyosis. METHODS: We examined the expression levels of miR-21 in specimens of adenomyotic tissue and benign cervical lesions using qRT-PCR. In primary cultures of cells isolated from the adenomyosis lesions, the effect of ICI82780 (an ER inhibitor) on miR-21 expression levels prior to E2 activation or after E2 deprivation were examined with qRT-PCR. We further assessed the effects of a miR-21 mimic or an inhibitor on proliferation, apoptosis, migration and autophagy of the cells. RESULTS: The expression level of miR-21 was significantly higher in adenomyosis tissues than in normal myometrium (P < 0.05). In the cells isolated from adenomyosis lesions, miR-21 expression level was significantly higher in E2 activation group than in ER inhibition + E2 activation group and the control group (P < 0.05); miR-21 expression level was significantly lower in cells in E2 deprivation+ER inhibition group than in E2 deprivation group and the control group (P < 0.05). The adenomyosis cells transfected with miR-21 inhibitor showed inhibited proliferation and migration, expansion of mitochondrial endoplasmic reticulum, increased lysosomes, presence of autophagosomes, and increased cell apoptosis, while transfection of the cells with the miR-21 mimic produced the opposite effects. CONCLUSION: MiR-21 plays an important role in promoting proliferation, migration, and antiapoptosis in adenomyosis cells by altering the cell ultrastructure, which may contribute to early pathogenesis of the disease. In addition to binding with E2, ER can also regulate miR-21 through other pathways to participate in the pathogenesis of adenomyosis, thus having a stronger regulatory effect on miR-21 than E2.

mtDNA regulates cGAS-STING signaling pathway in adenomyosis.

In various hyperproliferative disorders, damaged mitochondria can release mitochondrial DNA (mtDNA) into the cytoplasm, activating the cGAS-STING signaling pathway and subsequent immune imbalances. Our previous research has demonstrated that hypoxia plays a role in the development of adenomyosis (AM) by inducing mitochondrial dysfunction. However, the precise involvement of the cGAS-STING signaling pathway and mtDNA in AM remains unclear. Therefore, this study aims to investigate the relationship between mtDNA secretion, changes in the cGAS-STING signaling pathway, and the abnormal cellular proliferation observed in AM. We found the cGAS, STING, TBK1, p-TBK1, IRF3, and p-IRF3 proteins levels were significantly elevated in the tissues of patients with AM compared to the control group. Additionally, there was an increase in the expression of the pro-inflammatory cytokines IL-6 and IFN-α in the AM tissues. Hypoxia-induced an increase in the proliferation and migration abilities of endometrial stromal cells (ESCs), accompanied by the activation of the cGAS-STING signaling pathway and elevated levels of IFN-α. Furthermore, hypoxia promoted the leakage of mtDNA into the cytoplasm in AM ESCs, and the deletion of mtDNA reduced the activation of the cGAS-STING pathway. Moreover, knockdown of the STING gene inhibited the expression of TBK1, p-TBK1, IRF3, and p-IRF3 and suppressed the secretion of the inflammatory cytokines IL-6 and IFN-α. Furthermore, the migration and invasion abilities of AM ESCs were significantly diminished after STING knockdown. These findings provide valuable insights into the role of mtDNA release and the cGAS-STING signaling pathway in the pathogenesis of AM.

Extracellular vesicle-encapsulated miR-25-3p promotes epithelial-mesenchymal transition and migration of endometrial epithelial cells by inducing macrophage polarization.

The pathogenesis of adenomyosis is closely related to the epithelial-mesenchymal transition and macrophages. MicroRNAs have been extensively investigated in relation to the epithelial-mesenchymal transition in a range of malignancies. However, there is a paucity of research on extracellular vesicles derived from the eutopic endometrium of adenomyosis and their encapsulated microRNAs. In this study, we investigated the role of microRNA-25-3p derived from extracellular vesicles in inducing macrophage polarization and promoting the epithelial-mesenchymal transition in endometrial epithelial cells of patients with adenomyosis and controls. We obtained eutopic endometrial samples and isolated extracellular vesicles from the culture supernatant of primary endometrial cells. Real-time quantitative PCR analysis demonstrated that microRNA-25-3p was highly expressed in extracellular vesicles, as well as in macrophages stimulated by extracellular vesicles from eutopic endometrium of adenomyosis; and macrophages transfected with microRNA-25-3p exhibited elevated levels of M2 markers, while displaying reduced levels of M1 markers. After co-culture with the above polarized macrophages, endometrial epithelial cells expressed higher levels of N-cadherin and Vimentin, and lower protein levels of E-cadherin and Cytokeratin 7. It was revealed that microRNA-25-3p encapsulated in extracellular vesicles from eutopic endometrial cells could induce macrophage polarization toward M2, and the polarized macrophages promote epithelial-mesenchymal transition in epithelial cells. However, in vitro experiments revealed no significant disparity in the migratory capacity of endometrial epithelial cells between the adenomyosis group and the control group. Furthermore, it was observed that microRNA-25-3p-stimulated polarized macrophages also facilitated the epithelial-mesenchymal transition and migration of endometrial epithelial cells within the control group. Thus, the significance of microRNA-25-3p-induced polarized macrophages in promoting the development of adenomyosis is unclear, and macrophage infiltration alone may be adequate for this process. We emphasize the specificity of the local eutopic endometrial microenvironment and postulate its potential significance in the pathogenesis of adenomyosis.

Proteomic detection of COX-2 pathway-related factors in patients with adenomyosis.

Background: Investigating the relationship between cyclooxygenase-2 (COX-2) pathway-related factors and clinical features in patients with adenomyosis by proteomics could provide potential therapeutic targets. Methods: This study recruited 40 patients undergoing surgical hysterectomy and pathological diagnosis of adenomyosis, collected ectopic endometrial specimens, and recorded clinical data. The expression levels of COX-2 in ectopic uterus lesions were detected using the immunohistochemical (IHC) SP method. The 40 samples were then divided into a COX-2 low or high expression group. Five samples with the most typical expression levels were selected from each of the two groups and the differential proteins between the two groups were identified using label-free quantitative proteomics. WW domain-binding protein 2 (WBP2), interferon induced transmembrane protein 3 (IFITM3), and secreted frizzled-related protein 4 (SFRP4) were selected for further verification, and their relationships with COX-2 and clinical characteristics were analyzed. Results: There were statistically significant differences in the expression of WBP2, IFITM3, and SFRP4 between the COX-2 low and high expression groups (P < 0.01). The expressions of COX-2, IFITM3, and SFRP4 were significantly correlated with dysmenorrhea between the two groups (P < 0.05), but not with uterine size or menstrual volume (P > 0.05). However, there was no significant correlation between the expression of WBP2 and dysmenorrhea, uterine size, and menstruation volume in both the high expression and low expression groups (P > 0.05). Conclusions: COX-2, IFITM3, SFRP4, and WBP2 may be involved in the pathogenesis of adenomyosis. COX-2, IFITM3, and SFRP4 may serve as potential molecular biomarkers or therapeutic targets in dysmenorrhea in patients with early adenomyosis.

Estrogen Regulates Scribble Localization in Endometrial Epithelial Cells Through Acyl Protein Thioesterase (APT)-Mediated S-Palmitoylation in Adenomyosis.

Despite its prevalence and the severity of symptoms, little is known about the pathogenesis and etiology of adenomyosis. In our previous study, Scribble localization has been found to be partially translocated to cytoplasm; however, its regulatory mechanism is known. In consideration of the important role of supraphysiologic estrogen production in the endometrium in the development of adenomyosis, we analyzed the effect and mechanism of estrogen on Scribble localization in vivo and in vitro. Firstly, we found Scribble translocation from the basolateral membrane to the cytoplasm was easily to be seen in women and mice with adenomyosis (68% vs 27%, 60% vs 10% separately). After treatment with the S-palmitoylation inhibitor 2-bromopalmitate for 48H, cytoplasmic enrichment of Scribble and the reduced level of palm-Scribble was observed by immunofluorescence, Western blot, and acyl-biotin exchange palmitoylation assay. High estrogen exposure could not only induce partially cytoplasmic translocation of Scribble but also decrease the expression level of palm-Scribble, which can be recovered by estrogen receptor inhibitor ICI182,780. Based on following experiments, we found that estrogen regulated Scribble localization by APT through S-palmitoylation of Scribble protein. At last, IHC was performed to verify the expression of APT1 and APT2 in human clinical tissue specimens and found that they were all increased dramatically. Furthermore, positive correlations were found between APT1 or APT2 and aromatase P450. Therefore, our research may provide a new understanding of the pathogenesis of adenomyosis.

Dysregulated expression of GATA2 and GATA6 transcription factors in adenomyosis: implications for impaired endometrial receptivity.

OBJECTIVE: To study the effect of adenomyosis on the localized expression of the GATA binding proteins 2 and 6 (GATA2 and GATA6) zinc-finger transcription factors that are involved in proliferation of hematopoietic and endocrine cell lineages, cell differentiation, and organogenesis, potentially leading to impaired endometrial implantation. DESIGN: Laboratory based experimental study. SETTING: Academic hospital and laboratory. PATIENTS: Human endometrial stromal cells (HESCs) of reproductive age patients, 18-45 years of age, with adenomyosis were compared with patients with no pathology and leiomyomatous uteri as controls (n = 4 in each group, respectively). Additionally, midsecretory phase endometrial sections were obtained from patients with adenomyosis and control patients with leiomyoma (n = 8 in each group, respectively). INTERVENTIONS: GATA2 and GATA6 immunohistochemistry and H-SCORE were performed on the midsecretory phase endometrial sections from adenomyosis and leiomyoma control patients (n = 8 each, respectively). Control and adenomyosis patient HESC cultures were treated with placebo or 10-8 M estradiol (E2), or decidualization media (EMC) containing 10-8 M E2, 10-7 M medroxyprogesterone acetate, and 5 × 10-5 M cAMP for 6 and 10 days. Additionally, control HESC cultures (n = 4) were transfected with scrambled small interfering RNA (siRNA) (control) or GATA2-specific siRNAs for 6 days while adenomyosis HESC cultures (n = 4) were transfected with human GATA2 expression vectors to silence or induce GATA2 overexpression. MAIN OUTCOME MEASURES: Immunohistochemistry was performed to obtain GATA2 and GATA6 H-SCORES in adenomyosis vs. control patient endometrial tissue. Expression of GATA2, GATA6, insulin-like growth factor-binding protein 1 (IGFBP1), prolactin (PRL), progesterone receptor (PGR), estrogen receptor 1 (ESR1), leukemia inhibitory factor (LIF), and Interleukin receptor 11 (IL11R) messenger RNA (mRNA) levels were analyzed using by qPCR with normalization to ACTB. Silencing and overexpression experiments also had the corresponding mRNA levels of the above factors analyzed. Western blot analysis was performed on isolated proteins from transfection experiments. RESULTS: Immunohistochemistry revealed an overall fourfold lower GATA2 and fourfold higher GATA6 H-SCORE level in the endometrial stromal cells of patients with adenomyosis vs. controls. Decidual induction with EMC resulted in significantly lower GATA2, PGR, PRL and IGFBP1 mRNA levels in HESC cultures from patients with adenomyosis patient vs. controls. Leukemia inhibitory factor and IL11R mRNA levels were also significantly dysregulated in adenomyosis HESCs compared with controls. . Silencing of GATA2 expression in control HESCs induced an adenomyosis-like state with significant reductions in GATA2, increases in GATA6 and accompanying aberrations in PGR, PRL, ESR1 and LIF levels. Conversely, GATA2 overexpression via vector in adenomyosis HESCs caused partial restoration of the defective decidual response with significant increases in GATA2, PGR, PRL and LIF expression. CONCLUSION: In-vivo and in-vitro experiment results demonstrate that there is an overall inverse relationship between endometrial GATA2 and GATA6 levels in patients with adenomyosis who have diminished GATA2 levels and concurrently elevated GATA6 levels. Additionally, lower GATA2 and higher GATA6 levels, together with aberrant levels of important receptors and implantation factors, such as ESR1, PGR, IGFBP1, PRL, LIF, and IL11R mRNA in HESCs from patients with adenomyosis or GATA2-silenced control HESCs, support impaired decidualization. These effects were partially restored with GATA2 overexpression in adenomyosis HESCs, demonstrating a potential therapeutic target.

Activation of HAND2-FGFR signaling pathway by lncRNA HAND2-AS1 in adenomyosis†.

Heart and neural crest derivatives expressed transcript 2 (HAND2) is a critical mediator of progesterone action in endometrial stromal cells. Silencing of Hand2 expression in mouse uterus leads to an unopposed FGFR-mediated action that causes female mice infertility. To investigate the involvement of HAND2-FGFR signaling in pathogenesis of adenomyosis, immunohistochemistry, in situ hybridization, and quantitative real-time PCR were employed to assess gene expression in the normal endometrium, the paired eutopic endometrium and ectopic lesions obtained from women with adenomyosis. DNA methylation in the regions of HAND2 promoter and the first exon was also monitored in these samples. Our results revealed that HAND2 expression were dramatically reduced, but FGF9 expression and FGFR-ERK1/2-mediated MAPK signaling pathway were enhanced in the eutopic endometrium and ectopic lesions of patients with adenomyosis compared to the normal controls. Interestingly, expression of HAND2-AS1, a long noncoding RNA that resides adjacent to HAND2 in genome, was also reduced in adenomyosis. DNA methylation analysis revealed that the bidirectional promoter between HAND2 and HAND2-AS1, and the first exon of HAND2 gene was heavily methylated in the eutopic endometrium and the ectopic lesions of adenomyosis. To investigate the regulation of gene expression by HAND2-AS1, HAND2-AS1 expression was silenced in human endometrial stromal cells. In contrast to the downregulation of HAND2 in response to HAND2-AS1 silencing, FGF9 expression was augmented significantly. Endometrial stromal cells lacking HAND2-AS1 exhibited enhanced proliferation and migration potentials. Collectively, our studies revealed a new molecular mechanism by which HAND2-AS1 is involved in the pathogenesis of adenomyosis via modulating HAND2-FGFR-mediated signaling.

Expression of high-mobility group box-1 in eutopic/ectopic endometrium and correlations with inflammation-related factors in adenomyosis.

OBJECTIVE: To investigate the expression of HMGB1 and toll-like receptor 4 (TLR4) in adenomyosis eutopic/ectopic endometrium. METHODS: Twenty patients with adenomyosis and 20 controls, all undergoing laparoscopy, were recruited from September 2015 to July 2016. Samples were collected from the endometrium without adenomyosis (CE), the eutopic endometrium with adenomyosis (EuE), and the ectopic endometrium with adenomyosis (EE). The mRNA and protein expression of HMGB1 and TLR4, and interleukin-6 (IL-6) and interleukin-8 (IL-8) RNA expression levels were measured. RESULTS: The average age of the adenomyosis women was 43.4 ± 5.3 years; their BMI was 23.3 ± 2.3 kg/m2. The control group included women aged 38.8 ± 9.8 years, with BMI 22.2 ± 3.4 kg/m2. The mRNA expression levels of HMGB1, TLR4, IL-6, and IL-8 in the EE and EuE groups were higher than those in the CE group (p < .01), and those in the EE group were higher than those in the EuE group (p < .01). The protein expression levels of HMGB1 and TLR4 in the EE and EuE groups were higher than those in the CE group (p < .01); they were higher in the EE group than the ones in the EuE group (p < .01). HMGB1 mRNA was significantly positively correlated with TLR4 in EuE and EC patients (r = 0.538 and r = 0.916, p < .01), as well as with IL-6 (r = 0.470 and r = 0.976, p < .01) and IL-8 (r = 0.574 and r = 0.650, p < .01). CONCLUSIONS: The overexpression of HMGB1 and TLR4 in EuE and EE is positively correlated with IL-6 and IL-8 expression. The HMGB1 signaling-mediated immune-inflammatory system might be involved in the development of adenomyosis.

Application of elastography to diagnose adenomyosis and evaluate the degree of dysmenorrhea: a prospective observational study.

BACKGROUND: To determine whether there is a correlation between stiffness measured by strain elastography and the severity of dysmenorrhea and to determine the value of elastography in evaluating severe dysmenorrhea in patients with adenomyosis. METHODS: The correlation between tissue stiffness and dysmenorrhea was analyzed by performing elastography on premenopausal women diagnosed with adenomyosis. Expression levels of transforming growth factor-ß (TGF-ß), α-smooth muscle actin (α-SMA), and protein gene product 9.5 (PGP9.5) were detected by immunohistochemistry; the correlation of TGF-ß and α-SMA levels with the tissue stiffness and the degree of fibrosis was further analyzed. Also, the relationship of the PGP9.5 expression level with the tissue stiffness and degree of dysmenorrhea was determined. RESULTS: The degree of dysmenorrhea was significantly positively correlated with lesion stiffness in patients with adenomyosis but not with the uterine or lesion volume. The cutoff for the strain ratio was > 1.36 between the adenomyosis and control groups, with an area under the curve (AUC) of 0.987. For severe dysmenorrhea, the cutoff for the strain ratio was > 1.65 in patients with adenomyosis, with an AUC of 0.849. TGF-ß, α-SMA, and PGP9.5 expression levels were higher in adenomyotic lesions than in the endometrium of the adenomyosis and control groups. Both TGF-ß and α-SMA levels were positively correlated with the tissue stiffness and degree of fibrosis. Additionally, the expression level of PGP9.5 showed a positive correlation with the tissue stiffness and degree of dysmenorrhea. CONCLUSIONS: Elastography can be used to evaluate the degree of dysmenorrhea; the greater the tissue stiffness, the greater the degree of dysmenorrhea. In addition, elastography performed well in the diagnosis of adenomyosis and the evaluation of severe dysmenorrhea in patients with adenomyosis.

Endometriosis and adenomyosis: shared pathophysiology.

Endometriosis and adenomyosis are closely related disorders. Their pathophysiologies are extremely similar. Both tissues originate from the eutopically located intracavitary endometrium. Oligoclones of endometrial glandular epithelial cells with somatic mutations and attached stromal cells may give rise to endometriosis if they travel to peritoneal surfaces or the ovary via retrograde menstruation and/or may be entrapped in the myometrium to give rise to adenomyosis. In both instances, the endometrial cell populations possess survival and growth capabilities conferred by somatic epithelial mutations and epigenetic abnormalities in stromal cells. Activating mutations of KRAS are the most commonly found genetic variant in endometriotic epithelial cells, whereas the adenomyotic epithelial cells almost exclusively bear KRAS mutations. Epigenetic abnormalities in the stromal cells of endometriosis and adenomyosis are very similar and involve an abnormal expression pattern of nuclear receptors, including the steroid receptors. These epigenetic defects give rise to excessive local estrogen biosynthesis by aromatase and abnormal estrogen action via estrogen receptor-ß. Deficient progesterone receptor expression results in progesterone resistance in both endometriosis and adenomyosis.

Extracellular vesicles contribute to EMT in adenomyosis by inducing macrophage polarization†.

Adenomyosis is a benign disease, but it exhibits a metastatic property similar to tumors. Its pathogenesis is still unclear. One theory is that adenomyosis is the result of epithelial-mesenchymal transition (EMT) in displaced embryonic Muller cells. Macrophages accumulate in the eutopic endometrium of adenomyosis and play an important role in EMT and the pathogenesis of adenomyosis. Extracellular vesicles (EVs) are considered an important mechanism of intercellular communication, but few studies have shown the role of EVs between endometrial epithelial cells and macrophages. In this study, we collected the eutopic endometrium of adenomyosis, and acquired the primary endometrial cells, then isolated EVs from the culture supernatants. We identified the characteristics of EVs by transmission electron microscopy, nanoparticle tracking, and western blot, and then detected the mRNA expression levels of CD163, IL-10, iNOS, and TNF-α in macrophages by qRT-PCR after co-cultured with EVs; the expression levels of E-cadherin, CK7, N-cadherin, and Vimentin by Western blot, and the migration abilities of epithelial cells by Transwell assay. The results showed that macrophages were highly expressed in the mRNA levels of CD163, IL10, and TNF-α after treated by EVs from adenomyosis patients; endometrial epithelial cells expressed lower protein levels of E-cadherin and CK7, higher levels of N-cadherin and Vimentin after co-cultured with the above polarized macrophages; and the migration abilities of epithelial cells were enhanced. In conclusion, EVs derived from adenomyosis can induce macrophages to polarize toward M2b, and the polarized macrophages could, in turn, induce EMT process in endometrial epithelial cells.

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.

Increased NKG2A+CD8+ T-cell exhaustion in patients with adenomyosis.

Immune dysregulation has long been proposed to be associated with adenomyosis, but the underlying mediators and mechanisms remain largely unexplored. Here, we used flow cytometry to investigate the alterations in immune cell subsets in adenomyotic uteri and analyze the phenotype and function of abnormal immune cells. We found that an increase in cluster of differentiation (CD)8+ T-cell number was the predominant alteration in ectopic lesions in patients with adenomyosis and was significantly associated with the severity of adenomyosis. Importantly, we identified an exhausted natural killer group protein 2A (NKG2A)+CD8+ T-cell subset that was associated with the severity of adenomyosis and found that the number of these cells was significantly increased in the eutopic endometrium and ectopic lesions. In addition, the increases in the expression of NKG2A ligand histocompatibility leucocyte antigen E and interleukin-15 in glandular epithelial cells in the adenomyotic microenvironment might contribute to CD8+ T-cell exhaustion by promoting NKG2A expression on CD8+ T cells or inhibiting the effector function of these cells. In conclusion, our data revealed a previously unrecognized role for NKG2A+CD8+ T-cell exhaustion in the pathogenesis of adenomyosis, indicating that therapeutic interventions designed to target and reinvigorate exhausted CD8+ T cells may be beneficial for patients with adenomyosis.

Cytochrome-c-oxidase and ATPsynthase content increases in the endometrium of the patients with adenomyosis.

BACKGROUND: Adenomyosis is characterized by overgrowth of endometrial glands and stroma in the myometrium and is associated with reduced apoptosis. One of the key participants in one of the pathways of apoptosis is cytochrome c, whose expression can be regulated by actin-binding proteins involved in the formation of structures that provide cell motility. The aim of the study was to determine the content of actin-binding proteins, cytochrome c, and terminal members of the mitochondrial respiratory chain in endometrial biopsies of patients with adenomyosis and the control group. METHODS AND RESULTS: The content of all studied proteins was determined by Western blotting, and the mRNA content of the corresponding genes was determined by quantitative RT-PCR. The relative content of alpha-actinin1 and mRNA of the gene encoding it in biopsy specimens from patients with adenomyosis was higher than in controls by 86 and 84% (p < 0.05), respectively. The relative content of alpha-actinin4 did not change, as did cytochrome c. The content of cytochrome-c-oxidase and ATPsynthase in the group with adenomyosis exceeded the control level by 270 and 121% (p < 0.05), respectively, but the relative content of mRNA of these genes did not change, which may indicate a change in regulation at the level of protein synthesis. CONCLUSION: The results may indicate a local increase in the synthesis of ATP in pathological endometrial cells, which indicates the possible effectiveness of local application of H+-ATP synthase inhibitors (for example, macrolide antibiotic) to reduce the severity of clinical symptoms of 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/ß-catenin, transforming growth factor-ß, and nuclear factor-κB) may serve as hub genes. We reviewed the molecular mechanisms underlying the development of adenomyosis and summarized potential nonhormonal therapies.

Immunohistochemical expression of Drosha is reduced in eutopic and ectopic endometrium of women with adenomyosis.

The objective of this study was to evaluate the immunohistochemical expression of Dicer, Drosha, and Exportin-5 in the eutopic and ectopic endometrium of women with adenomyosis. Twenty-two paired ectopic and eutopic endometrium from women with adenomyosis and 10 eutopic endometrium samples from control women undergoing hysterectomy were included in the study. Paraffin-embedded tissue blocks were cut and stained for immunohistochemistry. The percentage of epithelial cells positively marked was identified digitally after an automated slide scanning process. Mann-Whitney test or Wilcoxon signed-rank test was performed for independent and paired groups, respectively. A lower expression of Drosha was observed in the eutopic endometrium of women with adenomyosis than in the eutopic endometrium of women without the disease (69.9±3.4% vs 85.2±2.9%, respectively) (P=0.016; 95%CI: 3.4 to 27.4%). We also detected lower Drosha expression in the ectopic endometrium of women with adenomyosis than in the eutopic endometrium of the same women (59.6±3.2% vs 69.9±3.4%, respectively) (P=0.004; 95%CI: 2.3 to 16.7%). Additionally, we observed a correlation between Drosha expression in the ectopic and paired eutopic endometrium (P=0.034, rho=0.454). No significant difference in Dicer or Exportin expression was observed. Predominant pattern of cytoplasmic staining for the anti-Drosha antibody and both a nuclear and cytoplasmic pattern for the anti-Exportin antibody were observed. Drosha expression was significantly lower in the endometrium of women with adenomyosis compared to the eutopic endometrium of asymptomatic women without the disease. Furthermore, its expression was lower in the ectopic endometrium but correlated to the paired eutopic endometrium.

SFRP4+IGFBP5hi NKT cells induced neural-like cell differentiation to contribute to adenomyosis pain.

Background: Adenomyosis is an estrogen-dependent gynecological disease. The pathogenesis of chronic pain, the main clinical symptom of adenomyosis, remains undefined. As a combination lymphocyte with both T-cell and natural killer (NK)-cell properties, NK T (NKT) cells play a role in immune defense against numerous diseases and modulate cell differentiation. Method: This study analyzed the tissue-cell samples from adenomyosis with or without pain by single-cell sequencing. Result: We found a specific population of secreted frizzled-related protein 4 (SFRP4)+NKT cells and a large amount of undifferentiated multipotent stem cells in the adenomyosis pain group. We discovered that a high expression of IGFBP5 in SFRP4+NKT cells could promote the differentiation of multipotent stem cells into neural-like cells via the single-cell trajectory. Through verification by the sample, we found that the degree of the expression of the neuronal marker NEFM was correlated with the duration of pain in adenomyosis patients. The expression of IGFBP5 was positively correlated with the pain scores of adenomyosis patients. Conclusion: Collectively, these findings suggest that SFRP4+IGFBP5hi NKT cells were capable of converting part of the stem cells into neurogenic cells and inducing adenomyosis pain.

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.