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

Role of inflammation and immune response in the pathogenesis of uterine fibroids: Including their negative impact on reproductive outcomes

Uterine fibroids (UFs), the most common tumors in women of reproductive age, are characterized by sex steroid-dependent growth and excessive deposition of extracellular matrix (ECM) surrounding UF smooth muscle cells. Women with symptomatic UFs experience heavy menstrual bleeding and consequent iron-deficiency anemia. They also have a risk of recurrent pregnancy loss, preterm birth, and cesarean delivery, indicating that UFs can negatively affect reproductive outcomes. Various types of immune cells, including innate and adaptive cells, are observed in UFs; however, the impact of these cells on the pathophysiology of UFs remains unclear. Inflammation may play important roles in the growth of UFs, and expression levels of proinflammatory and inflammatory cytokines, such as interleukin (IL)-1, IL-6, IL-10, TNF-α, and TGF-β, are upregulated in UFs. These cytokines play important roles in the interaction between growth factors and ECM that is regulated by the sex steroids estrogen and progesterone. Furthermore, proinflammatory mediators are upregulated in females with UFs, with higher expression levels in the endometrium with submucosal and intramural UFs than in the endometrium without UFs, indicating that these proinflammatory cytokines may impair endometrial receptivity, leading to implantation failure in in vitro fertilization programs. Hormonal treatments using gonadotropin releasing hormone analogs and the selective progesterone receptor modulator ulipristal acetate significantly shrink UFs and improve UF-related symptoms. These compounds can regulate local inflammation in UFs and adjacent myometrium. Controlling and improving local inflammation caused by UFs may represent a novel therapeutic strategy for UFs and potentially improve reproductive outcomes in women with symptomatic UFs.

Uterine fibroids: current research on novel drug targets and innovative therapeutic strategies

INTRODUCTION

Uterine fibroids, the most common nonmalignant tumors affecting the female genital tract, are a significant medical challenge. This article focuses on the most recent studies that attempted to identify novel non-hormonal therapeutic targets and strategies in UF therapy.

AREAS COVERED

This review covers the analysis of the pharmacological and biological mechanisms of the action of natural substances and the role of the microbiome in reference to UFs. This study aimed to determine the potential role of these compounds in UF prevention and therapy.

EXPERT OPINION

While there are numerous approaches for treating UFs, available drug therapies for disease control have not been optimized yet. This review highlights the biological potential of vitamin D, EGCG and other natural compounds, as well as the microbiome, as promising alternatives in UF management and prevention. Although these substances have been quite well analyzed in this area, we still recommend conducting further studies, particularly randomized ones, in the field of therapy with these compounds or probiotics. Alternatively, as the quality of data continues to improve, we propose the consideration of their integration into clinical practice, in alignment with the patient's preferences and consent.

The challenge of FIGO type 3 leiomyomas and infertility: Exploring therapeutic alternatives amidst limited scientific certainties

Uterine leiomyomas (ULs) are non-cancerous tumors composed of smooth muscle cells that develop within the myometrium and represent the most prevalent pathological condition affecting the female genital tract. Despite the volume of available research, many aspects of ULs remain unresolved, making it a "paradoxical disease" where the increase in available scientific literature has not been matched by an increase in solid evidence for clinical management. Fertility stands at the top of the list of clinical issues where the role of ULs is still unclear. The leiomyoma subclassification system, released by the International Federaion of Gynecology and Obstetrics (FIGO) in 2008, introduced a new and more effective way of categorizing uterine fibroids. The aim was to go beyond the traditional classification "subserosal, intramural and submucosal", facilitating a detailed examination of individual ULs impact on the female reproductive system. The "type 3 UL" is a special type of myoma, characterized by its complete myometrial development while encroaching the endometrium. It is a unique "hybrid" between a submucous and an intramural UL, that may exert a detrimental "double hit" mechanism, which is of particular interest in patients wishing pregnancy. To date, no robust evidence is available regarding the management of type 3 ULs. The aim of this narrative review is to provide a comprehensive overview of the physiopathological mechanisms that type 3 UL may exert on fertility, and to present new perspectives that may help us to better understand both the need for and the methods of treating this unique type of fibroid.

Impact of FIGO type 3 uterine fibroids on in vitro fertilization outcomes: A systematic review and meta-analysis

BACKGROUND

The effect of FIGO (the International Federation of Gynecology & Obstetrics) type 3 myomas on in vitro fertilization (IVF) is uncertain.

OBJECTIVES

To evaluate whether FIGO type 3 myomas affect IVF outcomes, through a systematic review and meta-analysis (CRD42022379700).

SEARCH STRATEGY

Electronic databases were searched until November 15, 2022.

SELECTION CRITERIA

Studies evaluating the effects of FIGO type 3 myomas on IVF outcome.

DATA COLLECTION AND ANALYSIS

Pooled results were expressed as odds ratios (OR) with 95% confidence intervals (CI). Heterogeneity was assessed using Higgins I2 . Sources of heterogeneity were explored with sensitivity and subgroup analyses.

MAIN RESULTS

In total, 1020 patients were included: 324 with FIGO type 3 myomas and 696 controls (without myomas). A pooled data analysis showed a significantly lower live birth rate (OR 2.16, 95% CI 1.55-3.01, I2  = 0%, P < 0.00001), clinical pregnancy rate (OR 2.06, 95% CI 1.52-2.81, I2  = 0%, P < 0.00001), and implantation rate (OR 1.77, 95% CI 1.35-2.32, I2  = 0%, P < 0.00001) in women with untreated myomas compared with controls. The number and size of fibroids correlated with a worsening of IVF outcomes.

CONCLUSIONS

FIGO type 3 myomas are significantly associated with a lower implantation rate, cumulative pregnancy rate, and live birth rate. Furthermore, their deleterious effect on the outcome of IVF increases further with increasing size and number. Nevertheless, no firm conclusions could be drawn about the potential benefits of surgery for FIGO type 3 uterine fibroids on IVF outcomes.

Pathways of Hypoxia-Inducible Factor (HIF) in the Orchestration of Uterine Fibroids Development

Uterine fibroids (UF) are common benign tumors in women. The course of UF is associated with troubling symptoms and the development of infertility and pregnancy pathology. Surgical treatment even implies hysterectomy, while pharmacological interventions are modestly effective. Classically, hypoxic metabolism is considered a hallmark of malignant tumor. However, the role of hypoxia-induced factor (HIF) is significant in benign tumors as well. Herein, we briefly review the basic biology of HIF-family proteins, outlining their possible roles in UF. Apart from theoretical justifications, we summarized 15 studies reporting increased expression of HIFs and downstream factors in UF samples. Altogether, data suggest that increased expression of the HIF-protein and altered expression of its dependent genes are presumed to be the factors leading to UF development. Thus, even without being a malignant tumor, UF is characterized by the strong involvement of HIF. This novel insight may give rise to further research in the direction of finding new prognostic markers and effective medicines against UF.

Feasibility and Surgical Outcomes of Hysteroscopic Myomectomy of FIGO Type 3 Myoma: A Systematic Review

The latest classification from the Fédération Internationale de Gynécologie et d'Obstétrique (FIGO) has reclassified type 3 myomas, changing their classification from intramural to submucosal. While hysteroscopic myomectomy is considered the gold standard treatment for patients experiencing symptoms from submucosal myomas, there are currently no specific guidelines available for managing type 3 myomas, and the optimal surgical approach remains uncertain. Methods: The search for suitable articles published in English was carried out using the following databases (PROSPERO ID CRD42023418602): MEDLINE, EMBASE, Global Health, The Cochrane Library (Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Cochrane Methodology Register), Health Technology Assessment Database, Web of Science and search register. Only original studies reporting data on hysteroscopic myomectomy of type 3 myoma were considered eligible. The main outcomes investigated were the effectiveness and feasibility of hysteroscopic myomectomy and reproductive outcomes after surgical treatment. Results: Two hundred and sixty-one studies were screened and nineteen of these were read for eligibility. Three studies encompassing 56 patients in total were included. Among the overall population studied, three patients needed an additional procedure to completely remove the myoma and five cases of post-surgical synechiae were recorded. No complications were reported. Of 42 patients wishing for pregnancy, the cumulative live birth rates before and after the hysteroscopic myomectomy were 14.3% and 42.9%, respectively. Conclusions: Hysteroscopic myomectomy appears to be a safe and feasible approach. Nevertheless, data reported in the literature are extremely scarce and based on studies with few patients enrolled. New evidence is needed to assess the safety and effectiveness of hysteroscopic treatment for FIGO type 3 myomas.

Endometrial Angiogenesis of Abnormal Uterine Bleeding and Infertility in Patients with Uterine Fibroids-A Systematic Review

Uterine fibroids are the most common benign tumors in women, with abnormal uterine bleeding (AUB) as the main reported symptom. Additionally, an association between fibroids and infertility has been established, especially if the fibroid protrudes in the uterine cavity. Hormonal therapy is associated with side-effects and as well as hysterectomy, which is incompatible with a desire to conceive. To improve treatment, it is essential to unravel the etiology of fibroid-related symptoms. We aim to evaluate endometrial angiogenesis in women with fibroids, with and without AUB, and the influence of pharmaceutical therapies in these patients. Furthermore, we explore the possible role of altered angiogenesis in patients with fibroids and infertility. We performed a systematic review according to PRISMA-guidelines (PROSPERO: CRD42020169061), and included 15 eligible studies. Endometrial expression of vascular endothelial growth factor (VEGF) and adrenomedullin was increased in patients with fibroids. This suggests aberrant angiogenesis, potentially involving disturbed vessel maturation, resulting in immature and fragile vessels. Treatment with gonadotropin-releasing hormone agonist, ulipristal acetate, and continuous oral contraception pills reduced several angiogenic parameters, including VEGF. If infertile and fertile patients with fibroids were compared, a significant decreased expression of the bone morphogenetic protein/Smad-protein pathway was found, possibly caused by the increased expression of transforming growth factor-beta. For future therapeutic development, these different angiogenic pathways could be of interest as possible targets to treat fibroid-related symptoms.

Surgical removal of FIGO type 0 and 1 fibroids ameliorates the expression of endometrial proinflammatory transcription factors and receptivity modulators

OBJECTIVE

To reveal whether hysteroscopic removal of the International Federation of Gynecology and Obstetrics (FIGO) types 0 and 1 fibroids makes any changes in the expression of homeobox genes (HOXA10, HOXA11), leukemia inhibitory factor, and nuclear factor-kappa B (NF-kB).

DESIGN

A case-control study.

SETTING

University-based in vitro fertilisation center.

PATIENT(S)

This study consisted of a total of 29 participants, 21 with FIGO types 0 and 1 fibroids and 8 with normal uterine cavity without fibroids.

INTERVENTION(S)

Patients in FIGO types 0 and 1 fibroids group underwent hysteroscopic myomectomy. The patients in the control group underwent laparoscopic tubal ligation. Endometrial cells were collected by flushing method from all participants before and 3 months after myomectomy. Real-time polymerase chain reaction was used to detect HOXA10, HOXA11, and LIF mRNA expressions in endometrial flushing samples. The relative expressions of homeobox and LIF mRNA were calculated with comparative ΔCt method. Endometrial NF-kB concentration was measured quantitatively by enzyme-linked immunosorbent assay.

MAIN OUTCOME MEASURE(S)

To compare endometrial HOXA10, HOXA11, and LIF mRNA expressions as well as endometrial NF-kB concentration before and after myomectomy.

RESULT(S)

Premyomectomy NF-kB levels of type 0 (4.22 ± 1.02 ng/mL) and type 1 fibroid (6.44 ± 2.30 ng/mL) were significantly higher than the values of control group (0.54 ± 0.10 ng/mL). Surgical removal of type 0 and 1 fibroids resulted in a significant decrease in endometrial NF-kB levels (1.33 ± 0.02 ng/mL vs 1.65 ± 0.27 ng/mL, respectively). In type 0 fibroid group, after myomectomy, there was a 11.1-fold increase in HOXA10 mRNA, 4.23-fold in HOXA11 mRNA, and 7.63-fold in LIF mRNA. In the type 1 fibroid group, after myomectomy, there was a 16.3-fold increase in HOXA10 mRNA, 8.34-fold in HOXA11 mRNA, and 9.38-fold in LIF mRNA. A nonsignificant change was detected in homeobox and LIF mRNA after tubal sterilization. A negative and significant correlation was found between endometrial NF-kB and HOXA10 (r=-0.67), HOXA11 (r=-0.71) and LIF (r=-0.54).

CONCLUSION(S)

High proinflammatory NF-kB concentration and low homeobox and LIF mRNA expressions were detected in the presence of type 0 or 1 fibroids that returned to normal values after hysteroscopic myomectomy.

SARS-CoV-2 Infection of Human Ovarian Cells: A Potential Negative Impact on Female Fertility

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may affect female reproductive health. Here, we investigated the potential of SARS-CoV-2 to infect the follicular microenvironment, in particular granulosa (GCs) and cumulus cells (CCs), thus providing evidence for a productive infection. GCs and CCs were recovered from women (n = 25) who underwent in vitro fertilization at the Assisted Reproductive Unit, Siena University Hospital. Follicular ovarian cells were co-cultured with SARS-CoV-2 and then analyzed by qPCR, immunofluorescence (IF), western blot (WB) and transmission electron microscopy (TEM). In addition, cell culture supernatant was used to infect VERO6 cells. We demonstrated the expression of cell host factors ACE2, TRPMSS2, BSG and CTSL, which are pivotal for the virus life cycle. Cultured GCs and CCs incubated with SARS-CoV-2 revealed productive SARS-CoV-2 infection at 24 h, 48 h and 72 h post-adsorption. Indeed, SARS-CoV-2 RNA, spike and nucleocapsid proteins were detected in GCs and CCs, and their cell culture supernatant successfully infected the standard VERO E6 cells. Finally, TEM showed full-size virions attached to the membrane and located inside the cytoplasm. This in vitro study reveals the susceptibility of human ovarian cells to SARS-CoV-2 infection, suggesting a potential detrimental effect of COVID-19 infection on female human fertility.