Effects of noncavity-distorting fibroids on endometrial gene expression and function

Deciphering endometrial dysfunction in patients with uterine myoma using endometrial organoids: a pilot study

RESEARCH QUESTION

What influence does an intramural myoma have on the endometrium, and how is this mediated?

DESIGN

Endometrium was collected from 13 patients with non-cavity-distorting intramural myomas (diameter ≤4 cm; International Federation of Gynecology and Obstetrics type 4) and 13 patients without myomas undergoing hysterectomy for benign cervical diseases with a similar clinical baseline. Endometrial organoids were established in vitro and induced to reach the secretory phase by oestrogen and progesterone. Transcriptome sequencing was conducted on endometrial organoids in both untreated and secretory stages from three individuals with myomas and three control participants. Immunofluorescence and real-time quantitative PCR (RT-qPCR) were performed on endometrial organoids from another 10 myoma patients and 10 control patients for validation.

RESULTS

The data revealed abnormally increased hormone receptor (PGR) levels in the untreated endometrial organoids with myomas, resulting in potentially abnormal glandular and vascular development. The aberrant responses to oestrogen and progestogen prompted further investigation into the secretory phase. The secretory endometrial organoids with myomas exhibited greater changes in acetyl-α-tubulin, ODF2 and TPPP, demonstrating likely decreased cilia, and COL6A1, used as a marker for increased extracellular matrix (ECM) modelling. Both untreated and secretory endometrial organoids with myoma showed an up-regulation of genes and pathways related to ECM mechanotransduction. The expression pattern of receptivity-related genes was disturbed in endometrial organoids with myoma.

CONCLUSIONS

This study is the first to reveal that intramural myomas create an abnormal hormonal and mechanical environment in the untreated and secretory endometrial organoids. The intramural myomas negatively impacted gene expression relating to endometrial glands, blood vessels, cilia and ECM, indicating that intramural myomas impair endometrial decidualization and receptivity.

Fibroids and Fertility

Uterine fibroids significantly impact women's reproductive health, influencing fertility potential and pregnancy outcomes. Their growth, often facilitated by hormonal influences like estrogen and progesterone, can cause considerable disruptions in the uterus, leading to symptoms and complications that impact the quality of life and reproductive prospects of women.This article provides an exhaustive discussion of uterine fibroids, including pathophysiology, their impact on endometrial function, receptivity, fertility, and pregnancy outcomes, and the management of infertility in patients with uterine fibroids. It underlines the critical role of uterine fibroids in women's reproductive health, emphasizing the importance of effective diagnosis and treatment to promote fertility and improve pregnancy outcomes.

A molecular staging model for accurately dating the endometrial biopsy

Natural variability in menstrual cycle length, coupled with rapid changes in endometrial gene expression, makes it difficult to accurately define and compare different stages of the endometrial cycle. Here we develop and validate a method for precisely determining endometrial cycle stage based on global gene expression. Our 'molecular staging model' reveals significant and remarkably synchronised daily changes in expression for over 3400 endometrial genes throughout the cycle, with the most dramatic changes occurring during the secretory phase. Our study significantly extends existing data on the endometrial transcriptome, and for the first time enables identification of differentially expressed endometrial genes with increasing age and different ethnicities. It also allows reinterpretation of all endometrial RNA-seq and array data that has been published to date. Our molecular staging model will significantly advance understanding of endometrial-related disorders that affect nearly all women at some stage of their lives, such as heavy menstrual bleeding, endometriosis, adenomyosis, and recurrent implantation failure.

Does non-cavity distorting intramural fibroid affect endometrium around the time of embryo implantation?

The effect of the intramural fibroids not distorting the cavity remains controversial on implantation and pregnancy. The aim of this study was to examine the impact of non-cavity distorting intramural fibroids on endometrium. Fifty-six women with non-cavity distorting intramural fibroid were recruited in this study. Paired endometrial specimens, one from beneath the fibroid (ipsilateral endometrium) and the other from the opposite side of uterine cavity, away from the fibroid (contralateral endometrium) were obtained 7-9 days after the luteinizing hormone surge in a natural cycle. Histological dating, Mucin1 and Glycodelin expression and uterine natural killer (uNK) cell density were compared between the paired samples. The median (IQR) H-score of Mucin1 staining in the ipsilateral luminal epithelium was 210% (142-230%), which was significantly (p < 0.05) higher than that of the contralateral luminal endometrium (157%, IQR 114-176%). There was no significant difference in Mucin1 expression in the glandular epithelium. There was no significant difference in Glycodelin expression in luminal and glandular epithelium, uNK cells density or histological dating results between the paired endometrial samples. In conclusion, it is uncertain whether the altered expression of Mucin1 in luminal epithelium alone may have impact on implantation when other markers are not changed.

MED12 mutation activates the tryptophan/kynurenine/AHR pathway to promote growth of uterine leiomyomas

Uterine leiomyomas cause heavy menstrual bleeding, anemia, and pregnancy loss in millions of women worldwide. Driver mutations in the transcriptional mediator complex subunit 12 (MED12) gene in uterine myometrial cells initiate 70% of leiomyomas that grow in a progesterone-dependent manner. We showed a distinct chromatin occupancy landscape of MED12 in mutant MED12 (mut-MED12) versus WT-MED12 leiomyomas. Integration of cistromic and transcriptomics data identified tryptophan 2,3-dioxygenase (TDO2) as the top mut-MED12 target gene that was significantly upregulated in mut-MED12 leiomyomas when compared with adjacent myometrium and WT-MED12 leiomyomas. TDO2 catalyzes the conversion of tryptophan to kynurenine, an aryl hydrocarbon receptor (AHR) ligand that we confirmed to be significantly elevated in mut-MED12 leiomyomas. Treatment of primary mut-MED12 leiomyoma cells with tryptophan or kynurenine stimulated AHR nuclear translocation, increased proliferation, inhibited apoptosis, and induced AHR-target gene expression, whereas blocking the TDO2/kynurenine/AHR pathway by siRNA or pharmacological treatment abolished these effects. Progesterone receptors regulated the expression of AHR and its target genes. In vivo, TDO2 expression positively correlated with the expression of genes crucial for leiomyoma growth. In summary, activation of the TDO2/kynurenine/AHR pathway selectively in mut-MED12 leiomyomas promoted tumor growth and may inform the future development of targeted treatments and precision medicine.

Uterine Transcriptome: Understanding Physiology and Disease Processes

In recent years, transcriptomics has enabled us to gain a deeper understanding of fundamental reproductive physiology, including the menstrual cycle, through a more precise molecular analysis. The endometrial mRNA transcript levels fluctuate during the normal menstrual cycle, indicating changes in the relative recruitment and abundance of inflammatory cells, as well as changes in the receptivity and remodeling of the endometrium. In addition to providing a more comprehensive understanding of the molecular underpinnings of pathological gynecological conditions such as endometriosis, leiomyomas, and adenomyosis through RNA sequencing, this has allowed researchers to create transcriptome profiles during both normal menstrual cycles and pathological gynecological conditions. Such insights could potentially lead to more targeted and personalized therapies for benign gynecological conditions. Here, we provide an overview of recent advances in transcriptome analysis of normal and pathological endometrium.

Observation of pregnancy outcomes in patients with hysteroscopic resection on submucous myomas

OBJECTIVE

The aim of this study was to assess postoperative pregnancy outcomes in patients with different types of submucous myomas after hysteroscopic resection.

MATERIALS AND METHODS

This retrospective unicentric study used data from the electronic medical records system of the hospital. All patients (n = 77) who underwent hysteroscopy for submucous myomas between November 2010 and December 2018 were included. Patients were divided into three groups according to the myoma classification (G0, G1, and G2). Medical files were reviewed and phone questionnaires were conducted to evaluate demographic characteristics, clinical features, surgical treatment, and pregnancy outcomes.

RESULTS

The median age of the patients was 32 (30.0, 34.0) years. The myoma diameter was 2.9 (2.0, 3.8) cm. The operation duration was 50.0 (30.0, 75.0) min. There were 15 patients in Group G0, 20 patients in Group G1, and 37 patients in Group G2. Follow-up data were available for 65 of the 77 patients. The total pregnancy rate was 58 (89.2%) of 65. The live birth rate was 41 (70.7%) of 58. There was no significant difference in pregnancy rate (G0 100% vs. G1 76.5% vs. G2 91.2%; p = 0.097) or in live birth rates among the three groups (G0 78.6% vs. G1 53.8% vs. G2 74.2%; p = 0.325).

CONCLUSION

There was no difference in pregnancy outcome among the three types of submucosal myomas. Our results support the idea that hysteroscopic myomectomy is an effective option for submucous myomas with good long-term pregnancy outcomes.

Extracellular matrix remodeling and inflammatory pathway in human endometrium: insights from uterine leiomyomas

OBJECTIVE

To compare the expression profiles of matrix metalloproteinases (MMPs) and their inhibitors (tissue inhibitors of matrix metalloproteinases, TIMPs) in the endometrium of women with and without type 3 leiomyomas and to understand their relationship with inflammatory status.

DESIGN

Molecular and in silico studies.

SETTING

University hospital.

PATIENT(S)

Patients with type 3 leiomyomas ranging from 3 to 10 cm in diameter (n = 18) and control age-matched women undergoing surgery for ovarian cysts (n = 18) who underwent endometrial biopsies.

INTERVENTION(S)

Endometrial biopsies.

MAIN OUTCOME MEASURE(S)

To evaluate the expression levels of MMPs and TIMPs in the endometrium, quantitative reverse transcriptase polymerase chain reaction and Western blot were performed. With the use of immunofluorescence analysis, the investigated proteins were localized in the tissues. The expression levels of inflammatory mediators such as IL-1β, IL-6, IL-10, TGF, COX1, COX2, STAT3, and VEGF were evaluated by quantitative reverse transcriptase polymerase chain reaction, and their relationships were detected by the STRING approach.

RESULT(S)

The endometrium of women with type 3 leiomyomas exhibited differential expression of MMPs and TIMPs, particularly MMP2, MMP11, and MMP14, as well as different topographic distribution, suggesting that leiomyomas may influence the endometrial molecular profile. Significant decreases in IL-1β, IL-6, and IL-10 expression, along with increases in COX1 and COX2, as well as VEGF, were highlighted. The STRING approach suggests that this altered gene expression profile may affect the Th17 cell differentiation pathway.

CONCLUSION(S)

The differential expression and localization of MMPs and TIMPs observed in women with type 3 leiomyomas, along with the reported derangement in the expression of key molecules involved in the inflammatory pathway, may contribute to changes in endometrial receptivity in these patients.

Understanding the Impact of Uterine Fibroids on Human Endometrium Function

Uterine fibroids (leiomyomas) are the most common benign gynecological tumors in women of reproductive age worldwide. They cause heavy menstrual bleeding, usually leading to severe anemia, pelvic pain/pressure, infertility, and other debilitating morbidities. Fibroids are believed to be monoclonal tumors arising from the myometrium, and recent studies have demonstrated that fibroids actively influence the endometrium globally. Studies suggest a direct relationship between the number of fibroids removed and fertility problems. In this review, our objective was to provide a complete overview of the origin of uterine fibroids and the molecular pathways and processes implicated in their development and growth, which can directly affect the function of a healthy endometrium. One of the most common characteristics of fibroids is the excessive production of extracellular matrix (ECM) components, which contributes to the stiffness and expansion of fibroids. ECM may serve as a reservoir of profibrotic growth factors such as the transforming growth factor β (TGF-β) and a modulator of their availability and actions. Fibroids also elicit mechanotransduction changes that result in decreased uterine wall contractility and increased myometrium rigidity, which affect normal biological uterine functions such as menstrual bleeding, receptivity, and implantation. Changes in the microRNA (miRNA) expression in fibroids and myometrial cells appear to modulate the TGF-β pathways and the expression of regulators of ECM production. Taken together, these findings demonstrate an interaction among the ECM components, TGF-β family signaling, miRNAs, and the endometrial vascular system. Targeting these components will be fundamental to developing novel pharmacotherapies that not only treat uterine fibroids but also restore normal endometrial function.

The role of magnetic resonance-guided focused ultrasound in fertility-sparing treatment of uterine fibroids-current perspectives

Uterine fibroids (UFs) are the most common benign tumours of the female reproductive system and the most frequent reason for hysterectomy worldwide. UFs are reported in 20%–70% of women of reproductive age depending on a study group. Although most women with UFs are asymptomatic, over 30% of them will present with different symptoms. Abnormal uterine bleeding, pain, pressure and infertility are the most common. Lesions that cause these kinds of symptoms may require medical intervention.

Trends in UF treatment change along with patient awareness and the introduction of new methods and techniques. Selecting an appropriate treatment option should be individualised and adjusted to the patient’s expectations as much as possible. This choice will mostly depend on the patient’s age, UF location, the size and number of lesions, severity of symptoms and, most importantly, the patient’s expectations concerning the preservation of fertility. Observations made for the past few years showed an increasing number of pre- and perimenopausal women who wish to preserve their uterus or decline surgery. In line with current trends and demands in medicine, great importance is attached to the development and upgrade of new minimally invasive or noninvasive procedures in UF therapy.

Magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) is not associated with severe destruction of the uterine cavity and walls. For this reason, this method may be considered as a kind of hope in fertility-sparing UF therapy and the data about its use in this indication raises future hope. In this review, we summarise the available data on the use of MR-HIFU as a fertility-sparing method in the treatment of UFs. We also indicate how it could evolve in the future.

According to the available data, MR-HIFU is a relatively safe noninvasive method which seems not to deteriorate fertility compared to the pre-treatment status. MR-HIFU may constitute an alternative solution and be chosen in patients who meet the qualification criteria and deny other methods, which also facilitates the use of other treatment options in case the procedure is ineffective. Further randomised studies are necessary to confirm the above information.

Large, Non-Cavity Distorting Intramural Leiomyomas Decrease Leukemia Inhibitory Factor in the Secretory Phase Endometrium

Despite mounting evidence that large intramural leiomyomas decrease fecundity during in vitro fertilization cycles, few studies have demonstrated a mechanism for this impact. We hypothesize that large intramural leiomyomas (IM) decrease the expression of endometrial implantation factors during the window of implantation. We prospectively recruited sub-fertile patients with IM 3 cm or greater in size planning myomectomy and performed endometrial biopsies the day of planned myomectomy (n = 9). Preoperative screening demonstrated no intercavitary lesions. Control endometrial samples were obtained from young, normally menstruating women free of uterine leiomyomas (n = 8). Endometrial samples were obtained in the mid-secretory phase (average cycle day for control patients and intramural leiomyoma patients were 24.5 and 21.3, respectively). Expression of implantation markers HOXA10, leukemia inhibitory factor (LIF), ER-α, and PR was compared using quantitative immunohistochemistry. Standard descriptive statistics were used to compare H-scores between the cohorts. Patients with intramural leiomyomas were found to have decreased LIF compared to controls (p value < 0.001). Expressions of HOXA10 and PR were no different between cohorts; however, ER-α showed a trend toward increased expression in the fibroid cohort (p value 0.07). LIF is downregulated in the endometrium of patients with large IM. This study is among the first to show decreased LIF expression in patients with uterine leiomyomas. We hypothesize that this difference from previously published work is due to sampling the endometrium at the height of LIF expression. Further work is needed to show if LIF downregulation is corrected with leiomyoma resection.

Uterine polyps, adenomyosis, leiomyomas, and endometrial receptivity

Endometrial polyps, adenomyosis, and leiomyomas are commonly encountered abnormalities frequently found in both fertile women and those with infertility. The clinician is frequently challenged to determine which of these entities, when found, is likely to impair fertility, and which are "innocent bystanders" unrelated to the problem at hand. Although removing an endometrial polyp may be seen as a relatively benign and safe intervention, myomectomy, and in particular adenomyomectomy, can be substantive surgical procedures, associated with their own potential for disrupting fertility. One of the mechanisms thought to be involved when these entities are contributing to infertility is an adverse impact on endometrial receptivity. Indeed polyps, adenomyosis, and leiomyomas have all been associated with an increased likelihood of abnormal endometrial molecular expressions thought to impair implantation and early embryo development. This review is designed to examine the relationship of these common entities to endometrial receptivity and to identify evidence gaps that should be considered when strategizing research initiatives. It is apparent that we have the tools necessary to fill these gaps, but it will be necessary to approach the issue in a strategic and coordinated fashion. It is likely that we will have to recognize the limitations of imaging alone and look to the evidence-based addition of molecular analysis to provide the individualized phenotyping of disease necessary for patient-specific treatment decisions.