Selective genetic analysis of myoma pseudocapsule and potential biological impact on uterine fibroid medical therapy

Summary of the Proceedings of the Basic Science of Uterine Fibroids Meeting: New Developments February 28, 2020

Scientists from multiple basic disciplines and an international group of physician-scientists from the field of obstetrics and gynecology presented recent studies and discussed new and evolving theories of uterine fibroid etiology, growth and development at The Basic Science of the Uterine Fibroids meeting, sponsored by the Campion Fund and the National Institute of Environmental Health Sciences. The purpose was to share up-to date knowledge and to stimulate new concepts regarding the basic molecular biology and pathophysiology of uterine fibroids, and to promote future collaborations. The meeting was held at the National Institute of Environmental Health Sciences in North Carolina on February 28, 2020. Speakers reviewed recent advances in cellular and molecular processes that contribute to fibroid growth and new opportunities for treatment. At the conclusion of the conference, attendees identified important new directions for future research.

The Biological Impact of Ulipristal Acetate on Cellular Networks Regulating Uterine Leiomyoma Growth

Uterine Fibroids (UFs), or leiomyomas, represent the most frequent pelvic tumor in reproductive-aged women. Although of benign origin, UFs decrease fertility and cause significant reproductive dysfunctions. Compared to normal myometrium, UFs are characterized by a clinical and molecular heterogeneity as demonstrated by the presence of multiple genetic alterations and altered signaling pathways. Recently, selective progesteronereceptor modulators (SPRM), as ulipristal acetate (UPA), have demonstrated their clinical benefits by reducing tumor growth and extracellular matrix deposition. For these reasons, UPA is used in the clinical practice as an intermittent treatment for women symptomatic for UFs or, sometimes, before a myomectomy. However, drug effects on signaling pathways frequently upregulated in UFs remain largely unknown. In fact, the mechanisms of action of the UPA on UFs and on the surrounding areas are not yet understood. To learn more about UPA molecular mechanisms, UF samples were treated ex vivo with UPA and profiled for drug effects on selected markers. During this preliminary ex vivo UPA administration, significant changes were observed in the expression levels of proteins related to cell cycle regulation, cytoskeleton remodeling, and drug resistance. The UPA administration reduced cofilin, Erk and Src phosphorylation, p27 and ezrin protein levels, but not Akt phosphorylation and cyclin D1 and β-catenin levels. This preliminary ex vivo biological analysis provided new insights into the mechanism of action of UPA in the treatment of UFs, which could better explain the biological functioning of the drug on UFs.

Submucous Fibroids, Fertility, and Possible Correlation to Pseudocapsule Thickness in Reproductive Surgery

Background and Objectives

Fibroids are related to infertility. Fibroid pseudocapsule is a neurovascular bundle surrounding leiomyomas rich of neurofibers involved in myometrial biology. Authors evaluated, by a case-control study, the fibroid pseudocapsule (FP) thickness by ultrasound (US) and the histological measurements, according to uterine location of fibroids.

Methods

137 consecutive patients undergoing hysterectomy for uterine myomas were enrolled and 200 myomas were evaluated. Before surgery, patients underwent an ultrasound (US) investigation to evaluate the number, the size, and the location of fibroids. After surgery, myoma-pseudocapsule-myometrium specimens were measured and evaluated by a single expert pathologist. Both US and histological data were collected and statistically analyzed.

Results

Our results confirm the relevant difference of FP thickness, particularly represented under the endometrium for submucous LMs. FPs near the endometrial cavity were considerably thicker than those of both intramural fibroids and subserous fibroids measured by US (P=0.0001) and histology (P=0.0001). A clear cut-off measurement at 2 mm (P=0.0001) was found between endometrial FPs and all other FPs for either US or histology measurements.

Conclusion

The thickness of FP is considerably higher near the endometrial cavity when compared to those of both intramural and subserous LMs, suggesting a potential role either in fertility or in myometrial healing.

Recent scientific advances in leiomyoma (uterine fibroids) research facilitates better understanding and management

Uterine leiomyomas (fibroids) are the most prevalent medical problem of the female reproductive tract, but there are few non-surgical treatment options. Although many advances in the understanding of the molecular components of these tumors have occurred over the past five years, an effective pharmaceutical approach remains elusive. Further, there is currently no clinical method to distinguish a benign uterine leiomyoma from a malignant leiomyosarcoma prior to treatment, a pressing need given concerns about the use of the power morcellator for minimally invasive surgery. This paper reviews current studies regarding the molecular biology of uterine fibroids, discusses non-surgical approaches and suggests new cutting-edge therapeutic and diagnostic approaches.