Epigenetic Features in Uterine Leiomyosarcoma and Endometrial Stromal Sarcomas: An Overview of the Literature

Could let-7f, miR-10b, miR-34a, miR-181b, and miR-181d Be Useful Tools as a Target Therapy for Uterine Leiomyosarcoma?

Background/Objectives: We have previously identified let-7f-5p, miR-10b-5p, miR-34a-5p, miR-181b-5p, and miR-181d-5p as differentially expressed between uterine leiomyoma (LM) and leiomyosarcoma (LMS) tissue samples. The present study aimed to characterize these miRNA expression profiles and to assess the functional role of miR-34a and miR-181b in uterine LM and LMS cells. Methods: All the selected miRNAs showed downregulation in LMS cells compared to LM cells, but only miR-34a and miR-181b expression patterns matched those of patient samples. Therefore, these two miRs were selected for further analyses. Results: Loss of function analysis demonstrated that miR-34a and miR-181b silencing inhibited LM cell proliferation and migration. MiR-34a silencing induced CCND1 and MDM4 expression and inhibited KMT2D, BCL2, and NOTCH2 in LM. Silencing of miR-181b promotes TIMP3 and FGFR1 expression in LM and diminishes BCL2, NOTCH2, ATM, IRS1, and PRLR. Gain of function analysis revealed that the introduction of miR-34a and miR-181b mimics suppressed proliferation and migration in malignant LMS cells. Additionally, transfection with a miR-34a mimic downregulated NOTCH2 and BCL2 expression and enhanced the expression of CCND1, KMT2D, and TP53 in LMS cells. Moreover, miR-181b overexpression decreased TIMP3, NOTCH2, ATM, and IRS1 expression and increased the expression of FGFR1 in this cell. Importantly, the single introduction of either a miR-34a or miR-181b mimic was able to decrease the invasion capacity of LMS cells. Conclusions: Our studies demonstrated that miR-34a or miR-181b may play an anti-oncogenic role in uterine tumors; further studies are needed to better understand the role and regulatory mechanism of these miRNAs in LMS cancer development, which will help provide prognostic and therapeutic options for patients with LMS.

Advancement in Multi-omics approaches for Uterine Sarcoma

Uterine sarcoma (US) is a rare malignant tumor that has various pathological types and high heterogeneity in the female reproductive system. Its subtle early symptoms, frequent recurrence, and resistance to radiation and chemotherapy make the prognosis for US patients very poor. Therefore, understanding the molecular mechanisms underlying tumorigenesis and progression is essential for an accurate diagnosis and targeted therapy to improve patient outcomes. Recent advancements in high-throughput molecular sequencing have allowed for a deeper understanding of diseases through multi-omics technologies. In this review, the latest progress and future potential of multi-omics technologies in US research is examined, and their roles in biomarker discovery and their application in the precise diagnosis and treatment of US are highlighted.

Comprehensive Review of Uterine Leiomyosarcoma: Pathogenesis, Diagnosis, Prognosis, and Targeted Therapy

Uterine leiomyosarcoma (uLMS) is the most common subtype of uterine sarcomas. They have a poor prognosis with high rates of recurrence and metastasis. The five-year survival for uLMS patients is between 25 and 76%, with survival rates approaching 10-15% for patients with metastatic disease at the initial diagnosis. Accumulating evidence suggests that several biological pathways are involved in uLMS pathogenesis. Notably, drugs that block abnormal functions of these pathways remarkably improve survival in uLMS patients. However, due to chemotherapy resistance, there remains a need for novel drugs that can target these pathways effectively. In this review article, we provide an overview of the recent progress in ascertaining the biological functions and regulatory mechanisms in uLMS from the perspective of aberrant biological pathways, including DNA repair, immune checkpoint blockade, protein kinase and intracellular signaling pathways, and the hedgehog pathway. We review the emerging role of epigenetics and epitranscriptome in the pathogenesis of uLMS. In addition, we discuss serum markers, artificial intelligence (AI) combined with machine learning, shear wave elastography, current management and medical treatment options, and ongoing clinical trials for patients with uLMS. Comprehensive, integrated, and deeper insights into the pathobiology and underlying molecular mechanisms of uLMS will help develop novel strategies to treat patients with this aggressive tumor.

miRNAs: From Master Regulators of Gene Expression to Biomarkers Involved in Intercellular Communication

MicroRNAs (miRNAs) are non-coding RNAs that act as master regulators of gene expression, fine-tuning the activity of thousands of genes in our cells, by modulating gene expression at the post-transcriptional level [...].

Intravenous metastasis of unexpected uterine sarcoma in the context of uterine fibroids: case report and literature review

Objective

Endometrial stromal tumors are rare and complex mesenchymal tumors that often present with clinical symptoms similar to uterine leiomyomas. Due to their atypical nature, they are prone to be misdiagnosed or overlooked by healthcare professionals. This study presents a case report of an incidentally discovered endometrial stromal sarcoma with venous metastasis, which was initially misdiagnosed as a uterine leiomyoma. In addition, this study reviews previously documented cases of similar tumors.

Case report

During a routine medical examination in 2016, a 50-year-old woman was diagnosed with uterine fibroids. In June 2020, she began experiencing moderate, irregular vaginal bleeding. Nevertheless, a histopathological examination indicated an endometrial stromal sarcoma with a striking amalgamation of both low-grade and high-grade features. Molecular analysis identified a rare MED12 gene mutation. The patient underwent total hysterectomy, bilateral salpingectomy, and resection of the metastatic lesions. Postoperative management included radiotherapy, chemotherapy, and hormone therapy. After completion of chemotherapy, the patient was followed up for 27 months with no evidence of tumor recurrence.

Conclusion

This case report highlights the importance of pathological, immunohistochemical, and molecular aspects of this rare tumor involving the inferior vena cava and showing the presence of atypical gene mutations. The successful treatment outcome further emphasizes the importance of advances in diagnostic modalities for managing rare tumors like this.

Next-Generation Sequencing Analysis of 3 Uterine Adenosarcomas with Heterogeneously Differentiated Genomic Mutations

Uterine adenosarcoma (UA) is an uncommon mixed tumor containing a benign to at most mildly atypical epithelial component and a sarcoma-like stroma, usually a low-grade, stromal component, with rare heterogeneous elements. Currently, tumor etiology is largely unknown. To better understand the gene mutations in UA, next-generation sequencing (NGS) technology analysis was performed. This study showed that two low-grade UAs with heterologous components had ATRX gene frameshift mutation, and one patient had a MED12 missense mutation. Copy number amplification genes were mainly observed on chromosome 12q13-15. In this study, PIK3/AKT/PTEN pathway mutations were found to be common in adenosarcoma. In addition, a rare BCORL1-PRR14L fusion mutation was also identified. These findings provide a basis for future research into these molecular changes in tumorigenesis and targeted therapy.

Clinical Features and Prognostic Factors in Patients With Uterine Leiomyosarcoma: A Single-Center Experience

Background Uterine leiomyosarcomas (LMS) are associated with more recurrence and higher mortality compared to other uterine cancers. Considering the limited number of case series in the literature, the limited effectiveness of standard treatment methods, and the inadequacy of molecular biomarkers, we planned to investigate the effects of treatment methods and survival outcomes in these patients. Methodology The study was designed retrospectively, and the records of patients who were followed up and treated at Ankara University Faculty of Medicine, Medical Oncology Clinic, between January 1, 2011, and December 31, 2021, were reviewed. Patients over 18 years of age with a pathological diagnosis of uterine LMS were included. Demographic, clinical, and pathological data were recorded using the hospital database. The International Federation of Gynecology and Obstetrics (FIGO) staging was reassessed for each patient in accordance with the AJCC Cancer Staging Manual, Eighth Edition (2017). Tumor size, location, and grade were also evaluated. Types of treatments, protocols, and adverse effects were recorded. Relapsed patients, relapse localization, and treatments given at relapse were recorded and compared.  Results Twenty-eight patients were included. The mean age of the patients was 53.7 years. The median follow-up time was 39.3 months. The localization of LMS could be detected in 22 (78.57%) patients, among them 20 (90.9%) patients had intramural, 1 (4.5%) had submucosal, and 1 (4.5%) had subserosal LMS. All patients (26, 92.8%) underwent primary surgery, except for 2 (7.14%) patients who were metastatic at the time of diagnosis. Adjuvant treatment suggestion was made for 7 (25%) patients with a high risk of recurrence in the multidisciplinary tumor council. Partial response was observed in 1 (3.5%) of the 2 (7.1%) metastatic patients, and stable disease was observed in the other. Recurrence was detected in 22 (84.6%) patients . Fifteen (53.6%) patients died during the follow-up period. Survival was better in premenopausal patients (99.2 versus 51.6 months, P = 0.056). No significant difference was found when the survival of patients who received and did not receive adjuvant treatment were compared. In relapsed patients, there was no significant difference in survival between patients who underwent and did not undergo surgical treatment. Conclusions Uterine LMS is a rare and aggressive malignancy with limited diagnostic methods, frequent recurrences, high mortality, and limited use of nonsurgical treatments. The positive effect of adjuvant treatment on survival has not been demonstrated. Further studies are needed to investigate the effect of hormone receptor status on prognosis and new biomarkers.

Integrated Bioinformatics Investigation of Novel Biomarkers of Uterine Leiomyosarcoma Diagnosis and Outcome

Uterine leiomyosarcomas (uLMS) have a poor prognosis and a high percentage of recurrent disease. Bioinformatics has become an integral element in rare cancer studies by overcoming the inability to collect a large enough study population. This study aimed to investigate and highlight crucial genes, pathways, miRNAs, and transcriptional factors (TF) on uLMS samples from five Gene Expression Omnibus datasets and The Cancer Genome Atlas Sarcoma study. Forty-one common differentially expressed genes (DEGs) were enriched and annotated by the DAVID software. With protein-protein interaction (PPI) network analysis, we selected ten hub genes that were validated with the TNMplotter web tool. We used the USCS Xena browser for survival analysis. We also predicted TF-gene and miRNA-gene regulatory networks along with potential drug molecules. TYMS and TK1 correlated with overall survival in uLMS patients. Finally, our results propose further validation of hub genes (TYMS and TK1), miR-26b-5p, and Sp1 as biomarkers of pathogenesis, prognosis, and differentiation of uLMS. Regarding the aggressive behavior and poor prognosis of uLMS, with the lack of standard therapeutic regimens, in our opinion, the results of our study provide enough evidence for further investigation of the molecular basis of uLMS occurrence and its implication in the diagnosis and therapy of this rare gynecological malignancy.

The Functional Role and Regulatory Mechanism of FTO m6A RNA Demethylase in Human Uterine Leiomyosarcoma

Uterine leiomyosarcoma (uLMS) is the most frequent subtype of uterine sarcoma that presents a poor prognosis and high rates of recurrence and metastasis. The origin and molecular mechanism underlying and driving its clinical and biological behavior remain largely unknown. Recently, we and others have revealed the role of microRNAs, DNA methylation, and histone modifications in contributing to the pathogenesis of uLMS. However, the connection between reversible m6A RNA methylation and uLMS pathogenesis remains unclear. In this study, we assessed the role and mechanism of FTO m6A RNA demethylase in the pathogenesis of uLMS. Immunohistochemistry analysis revealed that the levels of RNA demethylases FTO and ALKBH5 were aberrantly upregulated in uLMS tissues compared to adjacent myometrium with a significant change by histochemical scoring assessment (p < 0.01). Furthermore, the inhibition of FTO demethylase with its small, potent inhibitor (Dac51) significantly decreased the uLMS proliferation dose-dependently via cell cycle arrest. Notably, RNA-seq analysis revealed that the inhibition of FTO with Dac51 exhibited a significant decrease in cell-cycle-related genes, including several CDK members, and a significant increase in the expression of CDKN1A, which correlated with a Dac51-exerted inhibitory effect on cell proliferation. Moreover, Dac51 treatment allowed the rewiring of several critical pathways, including TNFα signaling, KRAS signaling, inflammation response, G2M checkpoint, and C-Myc signaling, among others, leading to the suppression of the uLMS phenotype. Moreover, transcription factor (TF) analyses suggested that epitranscriptional alterations by Dac51 may alter the cell cycle-related gene expression via TF-driven pathways and epigenetic networks in uLMS cells. This intersection of RNA methylation and other epigenetic controls and pathways provides a framework to better understand uterine diseases, particularly uLMS pathogenesis with a dysregulation of RNA methylation machinery. Therefore, targeting the vulnerable epitranscriptome may provide an additional regulatory layer for a promising and novel strategy for treating patients with this aggressive uterine cancer.

Targeting Class I Histone Deacetylases in Human Uterine Leiomyosarcoma

Uterine leiomyosarcoma (uLMS) is the most frequent subtype of uterine sarcoma that presents a poor prognosis, high rates of recurrence, and metastasis. Currently, the molecular mechanism of the origin and development of uLMS is unknown. Class I histone deacetylases (including HDAC1, 2, 3, and 8) are one of the major classes of the HDAC family and catalyze the removal of acetyl groups from lysine residues in histones and cellular proteins. Class I HDACs exhibit distinct cellular and subcellular expression patterns and are involved in many biological processes and diseases through diverse signaling pathways. However, the link between class I HDACs and uLMS is still being determined. In this study, we assessed the expression panel of Class I HDACs in uLMS and characterized the role and mechanism of class I HDACs in the pathogenesis of uLMS. Immunohistochemistry analysis revealed that HDAC1, 2, and 3 are aberrantly upregulated in uLMS tissues compared to adjacent myometrium. Immunoblot analysis demonstrated that the expression levels of HDAC 1, 2, and 3 exhibited a graded increase from normal and benign to malignant uterine tumor cells. Furthermore, inhibition of HDACs with Class I HDACs inhibitor (Tucidinostat) decreased the uLMS proliferation in a dose-dependent manner. Notably, gene set enrichment analysis of differentially expressed genes (DEGs) revealed that inhibition of HDACs with Tucidinostat altered several critical pathways. Moreover, multiple epigenetic analyses suggested that Tucidinostat may alter the transcriptome via reprogramming the oncogenic epigenome and inducing the changes in microRNA-target interaction in uLMS cells. In the parallel study, we also determined the effect of DL-sulforaphane on the uLMS. Our study demonstrated the relevance of class I HDACs proteins in the pathogenesis of malignant uLMS. Further understanding the role and mechanism of HDACs in uLMS may provide a promising and novel strategy for treating patients with this aggressive uterine cancer.