The biology of uterine sarcomas: A review and update

Current Treatment Options: Uterine Sarcoma

OPINION STATEMENT

The cornerstone of treatment for uterine sarcoma, regardless of histologic type, remains en bloc surgical resection with total hysterectomy. In the case of incidental diagnosis during another procedure, such as myomectomy, where a hysterectomy was not performed initially, completion hysterectomy or cervical remnant removal is recommended. The completion of additional surgical procedures, including bilateral salpingo-oophorectomy and lymphadenectomy, remains nuanced. Bilateral salpingo-oophorectomy remains controversial in the setting of most subtypes of uterine sarcoma, except in the case of hormone-receptor positivity, such as in low grade endometrial stromal sarcoma, where it is indicated as part of definitive surgical treatment. In the absence of apparent nodal involvement, we do not recommend performing universal lymphadenectomy for patients with sarcoma. We recommend systemic therapy for patients with extra-uterine or advanced stage disease, high-grade histology, and recurrence. The most active chemotherapy regimens for advanced, high-grade disease remain doxorubicin or gemcitabine and docetaxol combination therapy. A notable exception is low grade endometrial stromal sarcoma, where we recommend anti-hormonal therapy in the front-line setting. Radiation therapy is reserved for selected cases where it can aid in palliating symptoms.

Exploring the Clinicopathological Diversity in Sarcomatous Transformations in the Uterus

Introduction Uterine sarcomas are a rare group of mesenchymal tumors. They originate either from the uterine smooth muscle or from the endometrial stroma. The spectrum of malignant uterine sarcomatous transformations includes leiomyosarcoma, low-grade endometrial stromal sarcoma (LG-ESS), high-grade endometrial stromal sarcoma (HG-ESS), undifferentiated uterine sarcoma, and carcinosarcoma. The purpose of this study is to determine the distribution of malignant uterine sarcomatous transformations, in relation to the patient's age, epidemiological aspects, and clinical features, and to analyze the different histological types of uterine sarcomas diagnosed at our institution and thereby to quantify their frequency and determine the most common histopathological subtype occurring in the population. Materials and methods This was a retrospective descriptive study of 21 cases of malignant uterine sarcomatous transformations, diagnosed in Saveetha Medical College, Chennai, between January 2019 and December 2022. Data was collected from the archives of the department of pathology and from the department of medical records in the hospital. The spectrum of uterine sarcomas was analyzed in relation to the patient's age, menopausal status, presenting symptoms, preoperative diagnosis, biopsy and frozen section reports wherever available, and histopathological reports with pathological staging. Results The most common age group in which uterine sarcoma was diagnosed was found to be 61-70 years. All 10 patients who were diagnosed with carcinosarcoma were aged 60 years, and all seven patients diagnosed with low-grade endometrial stromal sarcoma were less than 50 years of age. Most of the patients were postmenopausal females, except for one patient who was premenopausal. The most common histological variety found was carcinosarcoma, malignant mixed mullerian tumor (47.6%), followed by LG-ESS (33.3%), leiomyosarcoma (14.28%), and HG-ESS (4.7%). Conclusion Uterine sarcomas are an aggressive group of tumors having a very poor prognosis. Due to its rarity and histopathological diversity, there is a lack of consensus on the risk factors.

Smooth Muscle Tumor of Uncertain Malignant Potential (STUMP): A Comprehensive Multidisciplinary Update

Background and Objectives: The uterine smooth muscle tumors of uncertain malignant potential (STUMP) are tumors with pathological characteristics similar to leiomyosarcoma, but that do not satisfy histological criteria for leiomyoma. These are problematic lesions with intermediate morphologic features; thus, diagnosis and treatment are difficult. This narrative review aims to review data in the literature about STUMPs, particularly focusing on management and therapeutic options and strategies for women who desire to preserve fertility. Material and Methods: authors searched for "uterine smooth muscle tumor of uncertain malignant potential" in PubMed and Scopus databases, from 2000 to March 2023. Pertinent articles were obtained in full-text format and screened for additional references. Only articles in English language were included. Studies including full case description of patients with histopathological diagnosis of STUMP in accordance with Stanford criteria were included. Results: The median age was 43 years old. Symptoms are similar to those of leiomyomas, with a mean diameter of 8.0 cm. Total hysterectomy with or without bilateral salpingo-oophorectomy is the standard care for women if fertility desire is satisfied. Myomectomy alone can be considered for young patients. Although these tumors have not a high malignant potential, several studies described recurrence and metastases. Conclusions: STUMPs are complex uterine smooth muscle tumors, with a rare but reasoned clinical-diagnostic management. Considering the high clinical and histological complexity of these tumors, high level of expertise is mandatory.

DPP6 and MFAP5 are associated with immune infiltration as diagnostic biomarkers in distinguishing uterine leiomyosarcoma from leiomyoma

Objective

Uterine leiomyosarcoma (ULMS) is the most common subtype of uterine sarcoma and is difficult to discern from uterine leiomyoma (ULM) preoperatively. The aim of the study was to determine the potential and significance of immune-related diagnostic biomarkers in distinguishing ULMS from ULM.

Methods

Two public gene expression profiles (GSE36610 and GSE64763) from the GEO datasets containing ULMS and ULM samples were downloaded. Differentially expressed genes (DEGs) were selected and determined among 37 ULMS and 25 ULM control samples. The DEGs were used for Gene Ontology (GO), Kyoto Encyclopaedia of Genes and Genomes (KEGG) and Disease Ontology (DO) enrichment analyses as well as gene set enrichment analysis (GSEA). The candidate biomarkers were identified by least absolute shrinkage and selection operator (LASSO) and support vector machine recursive feature elimination (SVM-RFE) analyses. The receiver operating characteristic curve (ROC) was applied to evaluate diagnostic ability. For further confirmation, the biomarker expression levels and diagnostic value in ULMS were verified in the GSE9511 and GSE68295 datasets (12 ULMS and 10 ULM), and validated by immunohistochemistry (IHC). The CIBERSORT algorithm was used to calculate the compositional patterns of 22 types of immune cells in ULMS.

Result

In total, 55 DEGs were recognized via GO analysis, and KEGG analyses revealed that the DEGs were enriched in nuclear division, and cell cycle. The recognized DEGs were primarily implicated in non-small cell lung carcinoma and breast carcinoma. Gene sets related to the cell cycle and DNA replication were activated in ULMS. DPP6 and MFAP5 were distinguished as diagnostic biomarkers of ULMS (AUC = 0.957, AUC = 0.899, respectively), and they were verified in the GSE9511 and GSE68295 datasets (AUC = 0.983, AUC = 0.942, respectively). The low expression of DPP6 and MFAP5 were associated with ULMS. In addition, the analysis of the immune microenvironment indicated that resting mast cells were positively correlated with DPP6 and MFAP5 expression and that eosinophils and M0 macrophages were negatively correlated with DPP6 expression (P<0.05).

Conclusion

These findings indicated that DPP6 and MFAP5 are diagnostic biomarkers of ULMS, thereby offering a novel perspective for future studies on the occurrence, function and molecular mechanisms of ULMS.

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

There is a consensus that epigenetic alterations play a key role in cancer initiation and its biology. Studies evaluating the modification in the DNA methylation and chromatin remodeling patterns, as well as gene regulation profile by non-coding RNAs (ncRNAs) have led to the development of novel therapeutic approaches to treat several tumor types. Indeed, despite clinical and translational challenges, combinatorial therapies employing agents targeting epigenetic modifications with conventional approaches have shown encouraging results. However, for rare neoplasia such as uterine leiomyosarcomas (LMS) and endometrial stromal sarcomas (ESS), treatment options are still limited. LMS has high chromosomal instability and molecular derangements, while ESS can present a specific gene fusion signature. Although they are the most frequent types of "pure" uterine sarcomas, these tumors are difficult to diagnose, have high rates of recurrence, and frequently develop resistance to current treatment options. The challenges involving the management of these tumors arise from the fact that the molecular mechanisms governing their progression have not been entirely elucidated. Hence, to fill this gap and highlight the importance of ongoing and future studies, we have cross-referenced the literature on uterine LMS and ESS and compiled the most relevant epigenetic studies, published between 2009 and 2022.

Comparative whole transcriptome analysis of gene expression in three canine soft tissue sarcoma types

Soft tissue sarcomas are pleiotropic tumors of mesenchymal cell origin. These tumors are rare in humans but common in veterinary practice, where they comprise up to 15% of canine skin and subcutaneous cancers. Because they present similar morphologies, primary sites, and growth characteristics, they are treated similarly, generally by surgical resection followed by radiation therapy. Previous studies have examined a variety of genetic changes as potential drivers of tumorigenesis and progression in soft tissue sarcomas as well as their use as markers for soft tissue sarcoma subtypes. However, few studies employing next generation sequencing approaches have been published. Here, we have examined gene expression patterns in canine soft tissue sarcomas using RNA-seq analysis of samples obtained from archived formalin-fixed and paraffin-embedded tumors. We provide a computational framework for using resulting data to categorize tumors, perform cross species comparisons and identify genetic changes associated with tumorigenesis. Functional overrepresentation analysis of differentially expressed genes further implicate both common and tumor-type specific transcription factors as potential mediators of tumorigenesis and aggression. Implications for tumor-type specific therapies are discussed. Our results illustrate the potential utility of this approach for the discovery of new therapeutic approaches to the management of canine soft tissue sarcomas and support the view that both common and tumor-type specific mechanisms drive the development of these tumors.

Natural Kinase Inhibitors for the Treatment and Management of Endometrial/Uterine Cancer: Preclinical to Clinical Studies

Endometrial cancer (EC) is the sixth most prevalent type of cancer among women. Kinases, enzymes mediating the transfer of adenosine triphosphate (ATP) in several signaling pathways, play a significant role in carcinogenesis and cancer cells’ survival and proliferation. Cyclin-dependent kinases (CDKs) are involved in EC pathogenesis; therefore, CDK inhibitors (CDKin) have a noteworthy therapeutic potential in this type of cancer, particularly in EC type 1. Natural compounds have been used for decades in the treatment of cancer serving as a source of anticancer bioactive molecules. Many phenolic and non-phenolic natural compounds covering flavonoids, stilbenoids, coumarins, biphenyl compounds, alkaloids, glycosides, terpenes, and terpenoids have shown moderate to high effectiveness against CDKin-mediated carcinogenic signaling pathways (PI3K, ERK1/2, Akt, ATM, mTOR, TP53). Pharmaceutical regimens based on two natural compounds, trabectedin and ixabepilone, have been investigated in humans showing short and midterm efficacy as second-line treatments in phase II clinical trials. The purpose of this review is twofold: the authors first provide an overview of the involvement of kinases and kinase inhibitors in the pathogenesis and treatment of EC and then discuss the existing evidence about natural products’ derived kinase inhibitors in the management of the disease and outline relevant future research.

Leiomyosarcoma of the Uterus: A Rare Diagnosis

Uterine leiomyosarcoma is a rare malignant tumor that accounts for almost 2-5% of all uterine malignancies. It has the highest prevalence during pre and perimenopause. Further, it clinically resembles benign conditions like leiomyoma, and the diagnosis is confirmed with the histologic findings of the mass. Here, we present the case of a 70-year-old female who presented with lower abdominal pain for two years. Exploratory laparotomy with hysterectomy was performed, and the diagnosis of leiomyosarcoma was confirmed after histological examination of the resected tumor.

Identification of uterine leiomyosarcoma-associated hub genes and immune cell infiltration pattern using weighted co-expression network analysis and CIBERSORT algorithm

BACKGROUND

While large-scale genomic analyses symbolize a precious attempt to decipher the molecular foundation of uterine leiomyosarcoma (ULMS), bioinformatics results associated with the occurrence of ULMS based totally on WGCNA and CIBERSORT have not yet been reported. This study aimed to screen the hub genes and the immune cell infiltration pattern in ULMS by bioinformatics methods.

METHODS

Firstly, the GSE67463 dataset, including 25 ULMS tissues and 29 normal myometrium (NL) tissues, was downloaded from the public database. The differentially expressed genes (DEGs) were screened by the 'limma' package and hub modules were identified by weighted gene co-expression network analysis (WGCNA). Subsequently, gene function annotations were performed to investigate the biological role of the genes from the intersection of two groups (hub module and DEGs). The above genes were calculated in the protein-protein interaction (PPI) network to select the hub genes further. The hub genes were validated using external data (GSE764 and GSE68295). In addition, the differential immune cell infiltration between UL and ULMS tissues was investigated using the CIBERSORT algorithm. Finally, we used western blot to preliminarily detect the hub genes in cell lines.

RESULTS

WGCNA analysis revealed a green-yellow module possessed the highest correlation with ULMS, including 1063 genes. A total of 172 DEGs were selected by thresholds set in the 'limma' package. The above two groups of genes were intersected to obtain 72 genes for functional annotation analysis. Interestingly, it indicated that 72 genes were mainly involved in immune processes and the Neddylation pathway. We found a higher infiltration of five types of cells (memory B cells, M0-type macrophages, mast cells activated, M1-type macrophages, and T cells follicular helper) in ULMS tissues than NL tissues, while the infiltration of two types of cells (NK cells activated and mast cells resting) was lower than in NL tissues. In addition, a total of five genes (KDR, CCL21, SELP, DPT, and DCN) were identified as the hub genes. Internal and external validation demonstrated that the five genes were over-expressed in NL tissues compared with USML tissues. Finally, the correlation analysis results indicate that NK cells activated and mast cells activated positively correlated with the hub genes. However, M1-type macrophages had a negative correlation with the hub genes. Moreover, only the DCN may be associated with the Neddylation pathway.

CONCLUSION

A series of evidence confirm that the five hub genes and the infiltration of seven types of immune cells are related to USML occurrence. These hub genes may affect the occurrence of USML through immune-related and Neddylation pathways, providing molecular evidence for the treatment of USML in the future.

Could MicroRNAs Be Useful Tools to Improve the Diagnosis and Treatment of Rare Gynecological Cancers? A Brief Overview

Gynecological cancers pose an important public health issue, with a high incidence among women of all ages. Gynecological cancers such as malignant germ-cell tumors, sex-cord-stromal tumors, uterine sarcomas and carcinosarcomas, gestational trophoblastic neoplasia, vulvar carcinoma and melanoma of the female genital tract, are defined as rare with an annual incidence of <6 per 100,000 women. Rare gynecological cancers (RGCs) are associated with poor prognosis, and given the low incidence of each entity, there is the risk of delayed diagnosis due to clinical inexperience and limited therapeutic options. There has been a growing interest in the field of microRNAs (miRNAs), a class of small non-coding RNAs of ∼22 nucleotides in length, because of their potential to regulate diverse biological processes. miRNAs usually induce mRNA degradation and translational repression by interacting with the 3' untranslated region (3'-UTR) of target mRNAs, as well as other regions and gene promoters, as well as activating translation or regulating transcription under certain conditions. Recent research has revealed the enormous promise of miRNAs for improving the diagnosis, therapy and prognosis of all major gynecological cancers. However, to date, only a few studies have been performed on RGCs. In this review, we summarize the data currently available regarding RGCs.

[Interdisciplinary S2k guidelines on the diagnosis and treatment of uterine sarcomas-recommendations for surgical pathology]

Uterine sarcomas represent a heterogeneous group of rare malignancies, derived from the myometrium, the endometrial stroma, and very rarely from the nonspecialized uterine soft tissue. The actual incidence is about 1.5 for Caucasian and 3.0 for Afro-American women. There is no grading system for leimoysarcoma defined by the WHO classification; however, if clinicians request, the FNCLCC grading can be specified in analogy to soft tissue sarcomas. Adenosarcomas must be distinguished from adenofibromas (the existence of which is questionable)-with the vast majority of these tumors being uterine adenosarcomas. Within adenosarcomas, deep myometrial invasion (>50%), sarcomatous overgrowth, and a high-grade heterologous component are associated with a higher recurrence rate and poor survival. The immunohistochemical panel represents a very helpful tool for distinguishing low-grade from high grade endometrial stromal sarcomas (ESS) and may be supplemented by molecular analyses. Steroid hormone receptor analysis should be performed for all ESS due to the possible therapeutic relevance. Undifferentiated uterine sarcomas represent a diagnosis of exclusion and have a very poor prognosis. Carcinosarcomas represent a special subtype of endometrial carcinomas and are in fact not uterine sarcomas. Uterine sarcomas may present substantial intratumoral heterogeneity and adequate embedding is mandatory. Lesions ≤2 cm in the largest dimension should be processed completely and larger tumors should be processed with one block per centimeter for the largest tumor dimension.

Biomaterial strategies to replicate gynecological tissue

Properties of native tissue can inspire biomimetic in vitro models of gynecological disease.

The mutational repertoire of uterine sarcomas and carcinosarcomas in a Brazilian cohort: A preliminary study

OBJECTIVES

The present study aimed to contribute to the catalog of genetic mutations involved in the carcinogenic processes of uterine sarcomas (USs) and carcinosarcomas (UCSs), which may assist in the accurate diagnosis of, and selection of treatment regimens for, these conditions.

METHODS

We performed gene-targeted next-generation sequencing (NGS) of 409 cancer-related genes in 15 US (7 uterine leiomyosarcoma [ULMS], 7 endometrial stromal sarcoma [ESS], 1 adenosarcoma [ADS]), 5 UCS, and 3 uterine leiomyoma (ULM) samples. Quality, frequency, and functional filters were applied to select putative somatic variants.

RESULTS

Among the 23 samples evaluated in this study, 42 loss-of-function (LOF) mutations and 111 missense mutations were detected, with a total of 153 mutations. Among them, 66 mutations were observed in the Catalogue of Somatic Mutations in Cancer (COSMIC) database. TP53 (48%), ATM (22%), and PIK3CA (17%) were the most frequently mutated genes. With respect to specific tumor subtypes, ESS showed mutations in the PDE4DIP, IGTA10, and DST genes, UCS exhibited mutations in ERBB4, and ULMS showed exclusive alterations in NOTCH2 and HER2. Mutations in the KMT2A gene were observed exclusively in ULM and ULMS. In silico pathway analyses demonstrated that many genes mutated in ULMS and ESS have functions associated with the cellular response to hypoxia and cellular response to peptide hormone stimulus. In UCS and ADS, genes with most alterations have functions associated with phosphatidylinositol kinase activity and glycerophospholipid metabolic process.

CONCLUSION

This preliminary study observed pathogenic mutations in US and UCS samples. Further studies with a larger cohort and functional analyses will foster the development of a precision medicine-based approach for the treatment of US and UCS.

Molecular differential diagnosis of uterine leiomyomas and leiomyosarcomas

Uterine leiomyomas (LM) and leiomyosarcomas (LMS) are considered biologically unrelated tumors due to their cytogenetic and molecular disparity. Yet, these tumors share morphological and molecular characteristics that cannot be differentiated through current clinical diagnostic tests, and thus cannot be definitively classified as benign or malignant until surgery. Newer approaches are needed for the identification of these tumors, as has been done for other tissues. The application of next generation sequencing enables the detection of new mutations that, when coupled to machine learning bioinformatic tools, advances our understanding of chromosomal instability. These approaches in the context of LM and LMS could allow the discovery of genetic variants and possible genomic markers. Additionally, the potential clinical utility of circulating cell-free tumor DNA could revolutionize the noninvasive detection and monitoring of these tumors. Here, we seek to provide a perspective on the molecular background of LM and LMS, recognizing their distinct molecular features that may lead to improved diagnosis and personalized treatments, which would have a measurable impact on women's reproductive health.

The Role of Eicosanoids in Gynecological Malignancies

Eicosanoids, bio-active lipid molecules, evoke a multitude of biological effects that directly affect cancer cells and indirectly affect tumor microenvironment. An emerging role has been shown for eicosanoids in the pathogenesis of gynecological malignancies which include cancers of the vulva, vagina, cervix, uterine, and ovary. Eicosanoid biosynthesis pathways start at the metabolism of phospholipids by phospholipase A2 then proceeding to one of three pathways: the cyclooxygenase (COX), lipoxygenase (LOX), or P450 epoxygenase pathways. The most studied eicosanoid pathways include COX and LOX; however, more evidence is appearing to support further study of the P450 epoxygenase pathway in gynecologic cancers. In this review, we present the current knowledge of the role of COX, LOX and P450 pathways in the pathogenesis of gynecologic malignancies. Vulvar and vaginal cancer, the rarest subtypes, there is association of COX-2 expression with poor disease specific survival in vulvar cancer and, in vaginal cancer, COX-2 expression has been found to play a role in mucosal inflammation leading to disease susceptibility and transmission. Cervical cancer is associated with COX-2 levels 7.4 times higher than in healthy tissues. Additionally, HPV elevates COX-2 levels through the EGFR pathway and HIV promotes elevated COX-2 levels in cervical tissue as well as increases PGE2 levels eliciting inflammation and progression of cancer. Evidence supports significant roles for both the LOX and COX pathways in uterine cancer. In endometrial cancer, there is increased expression of 5-LOX which is associated with adverse outcomes. Prostanoids in the COX pathway PGE2 and PGF2α have been shown to play a significant role in uterine cancer including alteration of proliferation, adhesion, migration, invasion, angiogenesis, and the inflammatory microenvironment. The most studied gynecological malignancy in regard to the potential role of eicosanoids in tumorigenesis is ovarian cancer in which all three pathways have shown to be associated or play a role in ovarian tumorigenesis directly on the tumor cell or through modulation of the tumor microenvironment. By identifying the gaps in knowledge, additional pathways and targets could be identified in order to obtain a better understanding of eicosanoid signaling in gynecological malignancies and identify potential new therapeutic approaches.

[Expressions of HELQ and RAD51C in endometrial stromal sarcoma and their clinical significance]

OBJECTIVE

To observe the expression of HELQ and RAD51C in normal endometrial and endometrial stromal sarcoma (ESS) and analyze their correlation with the clinical features of the patients.

METHODS

The expressions of HELQ and RAD51C proteins were detected by immunohistochemical staining in normal endometrial tissues (14 cases) and tumor tissues from patients with ESS (37 cases) treated in Hunan Provincial Cancer Hospital from January, 2013 to December, 2016. The correlations of the expressions of the two proteins with the patients'age, FIGO staging, tissue type, tumor size, and lymph node metastasis were analyzed.

RESULTS

Immunohistochemical staining showed that the expressions of HELQ and RAD51C were both decreased in ESS patients compared with the normal group, and there was a positive correlation between HELQ and RAD51C expression (P &lt; 0.05). HELQ expression in ESS was correlated with the tumor size and type. The expressions of HELQ and RAD51C were not correlated with the patients' age, FIGO stage and status of lymph node metastasis (P &gt; 0.05).

CONCLUSIONS

Homologous recombination- directed DNA repair involving HELQ and RAD51C may participate in the occurrence and progression of ESS.

Investigation on the Genomic Characterization of Uterine Sarcoma for rAd-p53 Combined with Chemotherapy Treatment

The aim is to investigate the genomic characterization of uterine sarcoma for rAd-p53 (Gendicine^®) combined with chemotherapy treatment. We recently published an article on 12 cases of uterine sarcomas, which were treated with rAd-p53 combined with chemotherapy. We found that rAd-p53 combined with chemotherapy is effective for various uterine sarcomas. Pretreatment pathological specimens of four uterine sarcoma patients were collected from the above recent clinical research and numbered 1-4A/B. Tumor samples were subjected to targeted sequencing by using a 416 genes panel. We profiled the mutation spectrum and tumor mutation burden in the tumors, identified mutated genes, and explored their gene function. We also verified the p53 protein expression using immunohistochemistry. We identified a total of 30 mutated genes that were found from the next-generation sequencing test results. The average number of mutated genes was up to seven in the five samples. TP53 gene was mutated in two of the four patients, No. 1 and No. 4B. They are c.C833G (p.P278R) missense mutation and a point mutation (C141*) that result in a premature stop codon. We did not find a mutated TP53 gene in the other two cases, but we identified mutated genes, including CREBBP, LYN, CDKN2A, and JAK2, which were located upstream of the TP53 gene; they may have an impact on TP53. We also identified 11 additional genes which are involved in p53-related signaling pathways or have interaction with p53. Compared to solid tumor mutational burden (TMB) distribution, none of their TMB was ranking in the top 25%. Mutant p53 protein expression was positive in two specimens. Our results demonstrated that the TP53 signaling pathway plays an important role in uterine sarcoma tumorigenesis. TP53 and the upstream genes such as CREBBP, LYN, CDKN2A, and JAK2 may be involved in the genomic characterization for rAd-p53 (Gendicine) combined with chemotherapy in uterine sarcoma. Besides, the average amount of mutated genes from every patient is large.

Therapeutic Implication of Genomic Landscape of Adult Metastatic Sarcoma

PURPOSE

This study investigated therapeutic potential of integrated genome and transcriptome profiling of metastatic sarcoma, a rare but extremely heterogeneous group of aggressive mesenchymal malignancies with few systemic therapeutic options.

METHODS

Forty-three adult patients with advanced or metastatic non-GI stromal tumor sarcomas of various histology subtypes who were enrolled in the Personalized OncoGenomics program at BC Cancer were included in this study. Fresh tumor tissues along with blood samples underwent whole-genome and transcriptome sequencing.

RESULTS

The most frequent genomic alterations in this cohort are large-scale structural variation and somatic copy number variation. Outlier RNA expression as well as somatic copy number variations, structural variations, and small mutations together suggest the presence of one or more potential therapeutic targets in the majority of patients in our cohort. Point mutations or deletions in known targetable cancer genes are rare; for example, tuberous sclerosis complex 2 provides a rationale for targeting the mammalian target of rapamycin pathway, resulting in a few patients with exceptional clinical benefit from everolimus. In addition, we observed recurrent 17p11-12 amplifications, which seem to be a sarcoma-specific event. This may suggest that this region harbors an oncogene(s) that is significant for sarcoma tumorigenesis. Furthermore, some sarcoma tumors carrying a distinct mutational signature suggestive of homologous recombination deficiency seem to demonstrate sensitivity to double-strand DNA-damaging agents.

CONCLUSION

Integrated large-scale genomic analysis may provide insights into potential therapeutic targets as well as novel biologic features of metastatic sarcomas that could fuel future experimental and clinical research and help design biomarker-driven basket clinical trials for novel therapeutic strategies.

Advanced uterine adenosarcoma with sarcomatous overgrowth in a young woman: A case report

RATIONALE

Uterine adenosarcoma (UA) with sarcomatous overgrowth (ASSO) is a rare and aggressive disease. Herein, wereported the case of a young patient with advanced uterine ASSO.

PATIENTS CONCERNS

A 29-year-old woman with the diagnoses of endometrial polyp and adenomyosis underwent hysteroscopic endometrial polypectomy for the giant endometrial polyp. Postoperative regular ultrasound scan indicated thickened endometriumand an ill-defined mass with continuous enlargement in the myometrium of the posterior wall of the uterus, which was considered as an adenomyoma. Two years after hysteroscopy, she was re-admitted due to lower abdominal distension and large pelvic mass. At that time, she had taken oral short-acting contraceptives for 2.5 years.

DIAGNOSES

Magnetic resonance imaging (MRI) of the pelvis revealed an irregular mass with the size of 12*56*107 mm in the right annex area, without distinct border with the rectum, moreover, an uneven intrauterine echo that has no obvious boundary with uterine wall. Right ovarian cancer and adenomyoma were initially considered.

INTERVENTIONS

The patient received transperitoneal retroperitoneal pelvic combined with total viscera resection, including uterus, bilateral appendages and rectum, omentectomy, appendectomy, lymphadenectomy, and ileostomy. Postoperative pathology confirmed ASSO in the uterine cavity and muscular layer, the whole cervical duct and the right adnexal. She underwent 2 systemic chemotherapy sessions after the surgery. The chemotherapy regimen was ifosfamide 2.5 g day 1 to 3, with liposomal doxorubicin 40 mg day 1.

OUTCOMES

The final diagnosis was uterine ASSO, International Federation of Gynecology and Obstetrics stage IVa. The patient has been following-up so far, with no progression.

LESSONS

Review of the case indicated that history of long-term oral short-acting contraceptives and giant endometrial polyps may be the high-risk factors for UA. For patients with high-risk factors, the follow-up ultrasound scan should be more frequently conducted. Moreover, 3D-ultrasound, MRI and outpatient hysteroscopy are recommended for routine screening. Placement of levonorgestrel-releasing intra-uterine system after hysteroscopy may be an effective intervention for patients with a high risk of giant polyps. Cluster of Differentiation 10, Estrogen receptor, Progesterone receptor, and nuclear antigen may be predictors for prognosis and selection of individualized treatment program.

Imaging in gynecological disease (15): clinical and ultrasound characteristics of uterine sarcoma

OBJECTIVE

To describe the clinical and ultrasound characteristics of uterine sarcomas.

METHODS

This was a retrospective multicenter study. From the databases of 13 ultrasound centers, we identified patients with a histological diagnosis of uterine sarcoma with available ultrasound reports and ultrasound images who had undergone preoperative ultrasound examination between 1996 and 2016. As the first step, each author collected information from the original ultrasound reports from his/her own center on predefined ultrasound features of the tumors and by reviewing the ultrasound images to identify information on variables not described in the original report. As the second step, 16 ultrasound examiners reviewed the images electronically in a consensus meeting and described them using predetermined terminology.

RESULTS

We identified 116 patients with leiomyosarcoma, 48 with endometrial stromal sarcoma and 31 with undifferentiated endometrial sarcoma. Median age of the patients was 56 years (range, 26-86 years). Most patients were symptomatic at diagnosis (164/183 (89.6%)), the most frequent presenting symptom being abnormal vaginal bleeding (91/183 (49.7%)). Patients with endometrial stromal sarcoma were younger than those with leiomyosarcoma and undifferentiated endometrial sarcoma (median age, 46 years vs 57 and 60 years, respectively). According to the assessment by the original ultrasound examiners, the median diameter of the largest tumor was 91 mm (range, 7-321 mm). Visible normal myometrium was reported in 149/195 (76.4%) cases, and 80.0% (156/195) of lesions were solitary. Most sarcomas (155/195 (79.5%)) were solid masses (> 80% solid tissue), and most manifested inhomogeneous echogenicity of the solid tissue (151/195 (77.4%)); one sarcoma was multilocular without solid components. Cystic areas were described in 87/195 (44.6%) tumors and most cyst cavities had irregular walls (67/87 (77.0%)). Internal shadowing was observed in 42/192 (21.9%) sarcomas and fan-shaped shadowing in 4/192 (2.1%). Moderate or rich vascularization was found on color-Doppler examination in 127/187 (67.9%) cases. In 153/195 (78.5%) sarcomas, the original ultrasound examiner suspected malignancy. Though there were some differences, the results of the first and second steps of the analysis were broadly similar.

CONCLUSIONS

Uterine sarcomas typically appear as solid masses with inhomogeneous echogenicity, sometimes with irregular cystic areas but only very occasionally with fan-shaped shadowing. Most are moderately or very well vascularized. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

The differential diagnoses of uterine leiomyomas and leiomyosarcomas using DNA and RNA sequencing

BACKGROUND

Although uterine leiomyomas and leiomyosarcomas are considered biologically unrelated tumors, they share morphologic and histologic characteristics that complicate their differential diagnosis. The long-term therapeutic option for leiomyoma is laparoscopic myomectomy with morcellation, particularly for patients who wish to preserve their fertility. However, because of the potential dissemination of undiagnosed or hidden leiomyosarcoma from morcellation, there is a need to develop a preoperative assessment of malignancy risk.

OBJECTIVE

Through an integrated comparative genomic and transcriptomic analysis, we aim to identify differential genetic targets in leiomyomas vs leiomyosarcomas using next-generation sequencing as the first step toward preoperative differential diagnosis.

STUDY DESIGN

Targeted sequencing of DNA and RNA coding regions for solid tumor-associated genes was performed on formalin-fixed paraffin-embedded samples from 13 leiomyomas and 13 leiomyosarcoma cases. DNA sequencing was used to identify copy number variations, single-nucleotide variants, and small insertions/deletions. RNA sequencing was used to identify gene fusions, splice variants, and/or differential gene expression profiles.

RESULTS

In leiomyosarcomas, tumor mutation burden was higher in terms of copy number variations, single nucleotide variants, small insertions/deletions, and gene fusions compared with leiomyomas. For copy number variations, 20 genes were affected by deletions in leiomyosarcomas, compared with 6 observed losses in leiomyomas. Gains (duplications) were identified in 19 genes in leiomyosarcomas, but only 3 genes in leiomyomas. The most common mutations (single-nucleotide variants and insertions/deletions) for leiomyosarcomas were identified in 105 genes of all analyzed leiomyosarcomas; 82 genes were affected in leiomyomas. Of note, 1 tumor previously diagnosed as leiomyosarcoma was established as inflammatory myofibroblastic tumor along this study with a novel ALK-TNS1 fusion. Finally, a differential transcriptomic profile was observed for 11 of 55 genes analyzed in leiomyosarcomas; 8.5% of initially diagnosed leiomyosarcomas showed high-confidence, novel gene fusions that were associated with these tumors.

CONCLUSION

Through integrated comparative genomic and transcriptomic analyses, we identified novel differential genetic targets that potentially differentiate leiomyosarcomas and leiomyomas. This provides a new insight into the differential diagnosis of these myometrial tumors.

Liquid Biopsy as a Tool for Differentiation of Leiomyomas and Sarcomas of Corpus Uteri

Utilization of liquid biopsy in the management of cancerous diseases is becoming more attractive. This method can overcome typical limitations of tissue biopsies, especially invasiveness, no repeatability, and the inability to monitor responses to medication during treatment as well as condition during follow-up. Liquid biopsy also provides greater possibility of early prediction of cancer presence. Corpus uteri mesenchymal tumors are comprised of benign variants, which are mostly leiomyomas, but also a heterogenous group of malignant sarcomas. Pre-surgical differentiation between these tumors is very difficult and the final description of tumor characteristics usually requires excision and histological examination. The leiomyomas and malignant leiomyosarcomas are especially difficult to distinguish and can, therefore, be easily misdiagnosed. Because of the very aggressive character of sarcomas, liquid biopsy based on early diagnosis and differentiation of these tumors would be extremely helpful. Moreover, after excision of the tumor, liquid biopsy can contribute to an increased knowledge of sarcoma behavior at the molecular level, especially on the formation of metastases which is still not well understood. In this review, we summarize the most important knowledge of mesenchymal uterine tumors, the possibilities and benefits of liquid biopsy utilization, the types of molecules and cells that can be analyzed with this approach, and the possibility of their isolation and capture. Finally, we review the typical abnormalities of leiomyomas and sarcomas that can be searched and analyzed in liquid biopsy samples with the final aim to pre-surgically differentiate between benign and malignant mesenchymal tumors.

Different methylation levels in the KLF4, ATF3 and DLEC1 genes in the myometrium and in corpus uteri mesenchymal tumours as assessed by MS-HRM

Mesenchymal tumours of the corpus uteri comprise common benign lesions - leiomyomas and very rare malignant variants - sarcomas. It can be difficult to distinguish between the particular types of mesenchymal tumours pre-surgically. Primarily, leiomyomas and the very aggressive leiomyosarcomas can be easily misdiagnosed when using only imaging devices. Therefore, a reliable non-invasive marker for these tumour types would provide greater certitude for patients that the lesion remains benign. Our collection comprises 76 native leiomyomas, an equal number of healthy myometrium samples and 49 FFPE samples of various types of sarcomas. The methylation level was assessed by MS-HRM method and we observed differences in the methylation level between healthy, benign and (semi)malignant tissues in the KLF4 and DLEC1 genes. The mean methylation levels of leiomyomas compared to myometrium and leiomyosarcomas were 70.7% vs. 6.5% vs. 39.6 % (KLF4) and 66.1% vs. 14.08% vs. 37.5% (DLEC1). The ATF3 gene was differentially methylated in leiomyomatous and myometrial tissues with 98.1% compared to 76.6%. The AUC values of the predictive logistic regression model for discrimination between leiomyomas and leiomyosarcomas based on methylation levels were 0.7829 (KLF4) and 0.7719 (DLEC1). Finally, our results suggest that there should be distinct models for the methylation events in benign leiomyomas and sarcomas, and that the KLF4 and DLEC1 genes can be considered potential methylation biomarkers for uterine leiomyomas.

Loss of ATRX/DAXX expression and alternative lengthening of telomeres in uterine leiomyomas

BACKGROUND

Uterine leiomyomas (ULs) are the most common gynecologic tumors and affect 3 of every 4 women by the age of 50 years. The majority of ULs are classified as conventional tumors, whereas 10% represent various histopathological subtypes with features that mimic malignancy. These subtypes include cellular and mitotically active ULs and ULs with bizarre nuclei. Uterine leiomyosarcoma (ULMS), the malignant counterpart of UL, is an aggressive cancer with poor overall survival. The early diagnosis and preoperative differentiation of ULMS from UL are often challenging because their symptoms and morphology resemble one another. Recent studies have shown frequent loss of alpha-thalassemia/mental retardation syndrome X-linked (ATRX) or death domain-associated protein (DAXX) expression in ULMS, and this is often associated with an alternative lengthening of telomeres (ALT) phenotype.

METHODS

To investigate ATRX and DAXX expression and the presence of ALT in UL subtypes, immunohistochemical and telomere-specific fluorescence in situ hybridization analyses were performed. The study material consisted of 142 formalin-fixed, paraffin-embedded tissue samples representing various UL subtypes and 64 conventional ULs.

RESULTS

A loss of ATRX or DAXX and/or ALT was detected in 6.3% of the histopathological UL subtype samples (9 of 142). Two patients whose ULs showed either ATRX loss or ALT were later diagnosed with a pulmonary smooth muscle tumor. Pulmonary tumors displayed molecular alterations found in the corresponding uterine tumors, which indicated metastasis to the lungs. All conventional ULs displayed normal ATRX, DAXX, and telomeres.

CONCLUSIONS

These results highlight the differences between conventional and histopathologically atypical ULs and indicate that some UL subtype tumors may harbor long-term malignant potential.

Next-generation Sequencing of an Ovarian Spindle Cell Tumor Identified an Ovarian Low-grade Endometrial Stromal Sarcoma: A Rare Entity

Ovarian spindle cell tumors comprise a heterogeneous group of ovarian neoplasms from benign to malignant. Since this morphologic finding describes a broad category of ovarian neoplasms, it is not easy to determine an accurate diagnosis. Low-grade endometrial stromal sarcoma (LG-ESS) is a rare gynecological malignancy that presents with spindle cell lesions. To identify ovarian LG-ESS, we performed whole-exome sequencing and transcriptome sequencing of a spindle cell tumor. The tumor harbored JAZF1-SUZ12, a well-known gene fusion commonly found in uterine LG-ESS. Moreover, 28 non-silent somatic mutations (13 frameshift, 12 missense, 2 nonsense and 1 splicing mutations) with five cancer-related genes (ACSL3, ATM, DST, HGF and PKHD1) were detected. Our results indicate that next-generation sequencing combined with conventional immunohistochemical analysis may be a better strategy than conventional analysis alone to identify ovarian LG-ESS with spindle cell lesions. Moreover, our data suggest that ovarian LG-ESS can harbor genetic characteristics similar to those of uterine LG-ESS.

Oncomirs Expression Profiling in Uterine Leiomyosarcoma Cells

MicroRNAs (miRNAs) are small non-coding RNAs that act as regulators of gene expression at the post-transcriptional level. They play a key role in several biological processes. Their abnormal expression may lead to malignant cell transformation. This study aimed to evaluate the expression profile of 84 miRNAs involved in tumorigenesis in immortalized cells of myometrium (MM), uterine leiomyoma (ULM), and uterine leiomyosarcoma (ULMS). Specific cell lines were cultured and qRT-PCR was performed. Thirteen miRNAs presented different expression profiles in ULM and the same thirteen in ULMS compared to MM. Eight miRNAs were overexpressed, and five were underexpressed in ULM. In ULMS cells, five miRNAs exhibited an overexpression and eight were down-regulated. Six miRNAs (miR-1-3p, miR-130b-3p, miR-140-5p, miR-202-3p, miR-205-5p, and miR-7-5p) presented a similar expression pattern in cell lines compared to patient samples. Of these, only three miRNAs showed significant expression in ULM (miR-1-3p, miR-140-5p, and miR-7-5p) and ULMS (miR-1-3p, miR-202-3p, and miR-7-5p). Our preliminary approach identified 24 oncomirs with an altered expression profile in ULM and ULMS cells. We identified four differentially expressed miRNAs with the same profile when compared with patients' samples, which strongly interacted with relevant genes, including apoptosis regulator (BCL2), epidermal growth factor receptor (EGFR), vascular endothelial growth factor A (VEGFA), insulin like growth factor 1 receptor (IGF1R),serine/threonine kinase (RAF1), receptor tyrosine kinase (MET), and bHLH transcription factor (MYCN). This led to alterations in their mRNA-target.

The selected biomarker analysis in 5 types of uterine smooth muscle tumors

Uterine smooth muscle tumors (USMTs) consist of a group of histologically heterogeneous and clinically diverse diseases ranging from malignant leiomyosarcoma (LMS) to benign leiomyoma (ULM). The genetic alterations in LMS are complex, with some genetic alterations present in both LMS and other atypical histologic variants of USMT. In this study, we reviewed 119 USMTs with a diagnosis of LMS, smooth muscle tumor of uncertain malignant potential, atypical leiomyomas/leiomyoma with bizarre nuclei, and cellular leiomyoma, as well as 46 ULMs and 60 myometrial controls. We selected 17 biomarkers highly relevant to LMS in 4 tumorigenic pathways including steroid hormone receptors (estrogen receptor [ER] and progesterone receptor [PR]), cell cycle/tumor suppressor genes, AKT pathway markers, and associated oncogenes. ER and PR expression was significantly lower in LMS than smooth muscle tumor of uncertain malignant potential, atypical leiomyomas/leiomyoma with bizarre nuclei, cellular leiomyoma, and ULM (P < .01). Sixty-five percent of LMSs showed complete loss of ER, and 75% of LMSs showed complete loss of PR. All cell cycle genes were differentially expressed in different types of tumor, but significant overlap was noted. More than 75% of LMSs had Ki-67 index greater than 33%, and only 5% in all other types of USMT. Expression of the selected oncogenes varied widely among different types of USMT. PR positivity and p53 had a borderline association with progression-free survival (P = .055 for PR and P = .0847 for p53). Furthermore, high PR expression was significantly associated with a longer overall survival (P = .0163, hazard ratio 0.198). Cell proliferative indices (Ki-67) and sex steroid hormone receptors were the most valuable markers in differentiating LMS from other USMT variants.

DNA fragmentation factors 40 and 45 (DFF40/DFF45) and B-cell lymphoma 2 (Bcl-2) protein are underexpressed in uterine leiomyosarcomas and may predict survival

OBJECTIVES

DNA fragmentation factors 40 and 45 (DFF40 and DFF45) are responsible for final DNA-laddering during apoptosis, whereas Bcl-2 (B-cell lymphoma 2) is an apoptosis inhibitor. Our aim was to investigate the expression of DFF40, DFF45, and Bcl-2 in uterine leiomyosarcomas (uLMS), leiomyomas (uLM), and the normal myometrium. Furthermore, the correlation between DFF40, DFF45, and Bcl-2 expression and clinicopathological parameters in leiomyosarcomas was assessed. Their prognostic value in disease-free survival (DFS) and overall survival (OS) was also calculated.

MATERIALS AND METHODS

This study included 53 cases of uLMS from patients matched for age and menopausal status with 53 cases of uLM and 53 controls of normal myometrium (uM). Case samples of uterine myometrium from leiomyosarcomas (uLMS-M) and leiomyomas (uLM-M) were also studied. Immunohistochemical scoring was undertaken for DFF40, DFF45, and Bcl-2.

RESULTS

DFF40, DFF45, and Bcl-2 were significantly underexpressed in uLMS compared with uLMS-M and uM. In uLMS samples, no correlation between the analyzed proteins was observed. Negative DFF40 and Bcl-2, but not DFF45, staining was a predictor of poorer DFS and OS in women with uLMS. uLM showed DFF40 and Bcl-2 overexpression compared with uM and uLM-M, with a significant positive correlation between DFF40 and DFF45. No differences in DFF40, DFF45, and Bcl-2 expression were observed between the uLMS-M, uLM-M, and uM samples, with a significant positive correlation between DFF40 and DFF45 expression.

CONCLUSION

DFF40, DFF45, and Bcl-2 are significantly underexpressed in uLMS, but only a lack of DFF40 and Bcl-2 negatively influences DFS and OS. Disruption of DFF40 and DFF45 expression was observed in uLMS, but not in uLM or control and case myometrium; this may play a role in tumor pathogenesis.

Vaginal metastasis as the initial presentation of leiomyosarcoma: a case report

BACKGROUND

Uterine leiomyosarcomas are very rare and highly aggressive tumors that have a high rate of recurrence and poor prognosis, even when early diagnosed. Due to their relative rarity, there is limited research on optimal management strategies.

CASE PRESENTATION

A 60-year-old woman with a history of an asymptomatic uterine leiomyoma presented in October 2015 with postmenopausal bleeding and a friable vaginal cyst that bled when palpated. A partial cystectomy was performed, and malignant-like cystic and solid components were identified. Histopathology diagnosed an unclassifiable malignant epithelioid tumor. Subsequent imaging studies identified a malignant uterine tumor, a metabolically active vaginal lesion, and two benign leiomyomas. An anterior pelvic exenteration (colpectomy, hysterectomy, bilateral adnexectomy, total cystectomy, and cutaneous ureteroileostomy ad modum Bricker) were performed by laparotomy in March 2016. Examination of the surgical specimens identified a 75 × 75-mm leiomyoma, an 80 × 30-mm infiltrating mesenchymal uterine lesion with vascular invasion and tumor emboli, and a 60 × 30-mm perivascular vaginal tumor. Immunohistochemistry indicated a phenotypic transition from a uterine leiomyosarcoma to a vaginal epithelioid lesion; marker expression changed from the uterine tumor actin+/desmin+/caldesmon+/CD10- phenotype, through the tumor emboli, to an actin-/desmin-/caldesmon-/CD10+ phenotype in the vaginal lesion. A high-grade uterine mesenchymal tumor and vaginal metastasis were diagnosed. Adjuvant chemotherapy with docetaxel, gemcitabine, and doxorubicin commenced in May 2016 and treatment has been well tolerated.

CONCLUSIONS

Differentiating leiomyosarcoma from leiomyoma is challenging and few tools other than microscopic evaluation are available. Vaginal compromise in leiomyosarcoma usually results from tumor extension, not hematogenous metastasis. A vaginal metastasis is a very rare initial presentation. We have found only two cases like this described on published literature. The atypical clinical and histological presentation in our case complicated diagnosis and delayed treatment. An early diagnosis and complete surgical clearance gives the best chance of survival, and imaging tools should be applied early in instances of new suspicious malignant lesions.

Endometrial adenosarcoma in the setting of a germline DICER1 mutation: A case report

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DICER1 mutations play a significant role in gynecologic malignancy.

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DICER1 may be involved in the sarcomagenesis of endometrial adenosarcoma.

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The knowledge of a genetic mutation can help clarify a patient's medical history.

Use of comprehensive genomic profiling to direct point-of-care management of patients with gynecologic cancers

OBJECTIVE

To determine the feasibility and clinical utility of using comprehensive genomic profiling (CGP) in the course of clinical care to identify clinically relevant tumor genomic alterations for patients with either rare or refractory gynecologic cancers to facilitate point-of-care management. Use of an expert, multidisciplinary, institutional molecular tumor board (MTB) assessment is discussed regarding input on putative targeted options for individualized therapy.

METHODS

A prospective clinical trial is ongoing. We report on the initial 69 patients with gynecologic cancers that were either rare or refractory to standard therapy. CGP was performed by Foundation Medicine, Inc. Genomic alterations were reviewed by members of an MTB. Consensus recommendations on genomically targeted, FDA-approved, on- and off-label therapies and clinical trials were sent to the treating physician, and decisions and outcomes were assessed.

RESULTS

Study outcomes were available for 64 patients. The mean number of genes altered per tumor was 4.97 (median=4; range, 1-26), and the average turnaround time from testing laboratory report to generation of formal recommendations was approximately three weeks. Evaluation of genomic and clinical data by the MTB led to generation of targeted treatment options in all 64 patients, and the percentage of patients for whom one or more of these recommendations were implemented by the treating physician was 39%. Sixty-four percent of the patients receiving targeted therapy based on a CGP result experienced radiologic response or showed evidence of clinical benefit or stable disease.

CONCLUSION

These data suggest that an institutional MTB is a feasible venue for reviewing tumor genomic profiling results and generating clinical recommendations. These data also support the need for further studies and guidelines on clinical decision making with greater availability of broad genomically based diagnostics.

Exome Sequencing of Uterine Leiomyosarcomas Identifies Frequent Mutations in TP53, ATRX, and MED12

Uterine leiomyosarcomas (ULMSs) are aggressive smooth muscle tumors associated with poor clinical outcome. Despite previous cytogenetic and molecular studies, their molecular background has remained elusive. To examine somatic variation in ULMS, we performed exome sequencing on 19 tumors. Altogether, 43 genes were mutated in at least two ULMSs. Most frequently mutated genes included tumor protein P53 (TP53; 6/19; 33%), alpha thalassemia/mental retardation syndrome X-linked (ATRX; 5/19; 26%), and mediator complex subunit 12 (MED12; 4/19; 21%). Unlike ATRX mutations, both TP53 and MED12 alterations have repeatedly been associated with ULMSs. All the observed ATRX alterations were either nonsense or frameshift mutations. ATRX protein levels were reliably analyzed by immunohistochemistry in altogether 44 ULMSs, and the majority of tumors (23/44; 52%) showed clearly reduced expression. Loss of ATRX expression has been associated with alternative lengthening of telomeres (ALT), and thus the telomere length was analyzed with telomere-specific fluorescence in situ hybridization. The ALT phenotype was confirmed in all ULMSs showing diminished ATRX expression. Exome data also revealed one nonsense mutation in death-domain associated protein (DAXX), another gene previously associated with ALT, and the tumor showed ALT positivity. In conclusion, exome sequencing revealed that TP53, ATRX, and MED12 are frequently mutated in ULMSs. ALT phenotype was commonly seen in tumors, indicating that ATR inhibitors, which were recently suggested as possible new drugs for ATRX-deficient tumors, could provide a potential novel therapeutic option for ULMS.

Uterine leiomyosarcomas are rare, malignant smooth muscle tumors with a poor 5-year survival and high recurrence rate. They account for 1–2% of all uterine malignancies with an estimated incidence of 0.4/100,000 women per year. The symptoms and signs of this tumor type widely overlap with those of common benign uterine leiomyomas, making early diagnosis of uterine leiomyosarcomas difficult. Currently, the diagnosis of these tumors is often incidental and postoperative. Despite previous cytogenetic and molecular studies, their molecular background has remained elusive. Identification of novel molecular genetic characteristics in uterine leiomyosarcomas is clinically relevant to further improve the diagnosis and prognosis of the patients. Here, we performed exome sequencing on 19 tumors, revealing frequent mutations in TP53, ATRX, and MED12. The discovery of frequent inactivating ATRX mutations provides a potential novel therapeutic target for uterine leiomyosarcomas.

May Sonic Hedgehog proteins be markers for malignancy in uterine smooth muscle tumors?

Several studies have demonstrated that the Sonic Hedgehog signaling pathway (SHH) plays an important role in tumorigenesis and cellular differentiation. We analyzed the protein expression of SHH pathway components and evaluated whether their profile could be useful for the diagnosis, prognosis, or prediction of the risk of malignancy for uterine smooth muscle tumors (USMTs). A total of 176 samples (20 myometrium, 119 variants of leiomyoma, and 37 leiomyosarcoma) were evaluated for the protein expression of the SHH signaling components, HHIP1 (SHH inhibitor), and BMP4 (SHH target) by immunohistochemistry. Western blot analysis was performed to verify the specificity of the antibodies. We grouped leiomyoma samples into conventional leiomyomas and unusual leiomyomas that comprise atypical, cellular, mitotically active leiomyomas and uterine smooth muscle tumors of uncertain malignant potential. Immunohistochemical analysis showed that SMO, SUFU, GLI1, GLI3, and BMP4 expression gradually increased depending on to the histologic tissue type. The protein expression of SMO, SUFU, and GLI1 was increased in unusual leiomyoma and leiomyosarcoma samples compared to normal myometrium. The inhibitor HHIP1 showed higher expression in myometrium, whereas only negative or basal expression of SMO, SUFU, GLI1, and GLI3 was detected in these samples. Strong expression of SHH was associated with poorer overall survival. Our data suggest that the expression of SHH proteins can be useful for evaluating the potential risk of malignancy for USMTs. Moreover, GLI1 and SMO may serve as future therapeutic targets for women with USMTs.

Mixed endometrial stromal and smooth muscle tumor with heart metastasis: report of a case and review of literature

We presented a case of mixed endometrial stromal sarcoma and smooth muscle cell tumor of the uterus with intravenous metastasis into the right heart. 50 hot mutated key genes of solid tumors were detected by next generation sequencing. The literature about the diagnostic and therapeutic strategies of the disease were reviewed.

Targeted genomic analysis of Müllerian adenosarcoma

Müllerian adenosarcoma (MA) is a rare mixed mesenchymal tumour of the female genital tract, composed of malignant stroma and benign-appearing epithelium. Sarcomatous overgrowth (SO) is the only established histological variable associated with higher stage and shorter survival. Specific molecular or immunohistochemistry (IHC) tools for the diagnosis of MA are lacking. Our goal was to study genomic mutations and copy number variations (CNVs) in MA to understand better its pathobiology, and develop specific diagnostic and prognostic tools. DNA was extracted from 20 samples of MA from 18 subjects (12 without SO and 6 with SO), including two in which areas of both typical MA histology and SO were independently tested. Samples were analysed using a targeted next-generation sequencing assay interrogating exonic sequences of 275 cancer genes for mutations and CNVs as well as 91 introns across 30 genes for cancer-associated rearrangements. The mean number of mutations in MA with SO (mean 9.7; range 3-14) did not differ significantly from that in MA without SO (mean 9.6; range 5-16). MA with SO had significantly higher mean numbers of gene-level CNVs (24.6) compared to MA without SO (5; p = 0.0002). The most frequent amplification involved MDM2 and CDK4 (5/18; 28%), accompanied by focal CDK4 and MDM2 and diffuse HMGA2 expression using immunohistochemistry. MYBL1 amplification was seen in 4/18 (22%), predominantly in SO. Alterations in PIK3CA/AKT/PTEN pathway members were seen in 13/18 (72%). Notably, TP53 mutations were uncommon, present in only two cases with SO. Three out of 18 (17%) had mutations in ATRX, all associated with SO. No chromosomal rearrangements were identified. We have identified a number of recurrent genomic alterations in MA, including some associated with SO. Although further investigation of these findings is needed, confirmation of one or more may lead to new mechanistic insights and novel markers for this often difficult-to-diagnose tumour.

The regulatory function of miR-200c on inflammatory and cell-cycle associated genes in SK-LMS-1, a leiomyosarcoma cell line

Uterine leiomyosarcoma is a relatively rare malignancy with high mortality due to metastasis and chemoresistance. Leiomyosarcomas share similar morphological characteristics with leiomyomas which are considered to have the potential of transformation into leiomyosarcoma. Accumulated evidence suggests that microRNAs acting as regulators of gene expression at the posttranscriptional level play key roles in diverse biological processes including cellular transformation and tumorigenesis. We hypothesized that miR-200c, whose expression is altered in leiomyomas, equally plays a key role in pathogenesis of leiomyosarcoma. Using SK-LMS-1 leiomyosarcoma cell line as an in vitro model here, we found that the level of expression of miR-200c was significantly lower as compared to isolated leiomyoma smooth muscle cells. Overexpression (gain-of-function) of miR-200c in SK-LMS-1 through direct interaction with 3'-untranslated region of IKBKB, IL8, CDK2, and CCNE2, respectively, resulted in suppression of their expression as determined by quantitative polymerase chain reaction and Western blot analysis. Additionally, gain-of-function of miR-200c through inhibition of IKBKB expression resulted in decreased p65 transcriptional activity in IL8 promoter. Gain-of-function of miR-200c also increased SK-LMS-1 caspase 3/7 activity and inhibited their proliferation and migration. In summary, the results suggest that a progressive decline in miR-200c expression which alters transcriptional regulation of specific target genes that control nuclear factor-κB signaling pathway, inflammation, cell cycle, and migration, in part may promote development and progression of leiomyosarcomas, including their transformation from leiomyomas.