MiR-543 Inhibits the Migration and Epithelial-To-Mesenchymal Transition of TGF-ß-Treated Endometrial Stromal Cells via the MAPK and Wnt/ß-Catenin Signaling Pathways.

Intrauterine adhesion (IUA) is one of the most prevalent reproductive system diseases in females. MicroRNAs (miRNAs) are reported to be master regulators in a variety of diseases, including IUA, but the role of microRNA-543 (miR-543) in IUA remains to be elucidated. In this study, we observed that miR-543 was downregulated in transforming growth factor-beta (TGF-ß)-treated endometrial stromal cells (ESCs). Functionally, we observed that miR-543 suppressed the migration, epithelial-to-mesenchymal transition (EMT), and inhibited expression of extracellular matrix (ECM) proteins in TGF-ß-treated ESCs. Mechanistically, MAPK1 is targeted by miR-543 after prediction and screening. A luciferase reporter assay demonstrated that miR-543 complementarily binds with the 3' untranslated region of mitogen-activated protein kinase 1 (MAPK1), and western blot analysis indicated that miR-543 negatively regulates MAPK1 protein levels. In addition, results from rescue assays showed that miR-543 inhibits the migration and EMT of TGF-ß-treated ESCs by targeting MAPK1. In addition, we observed that miR-543 inactivates the Wnt/ß-catenin signaling pathway through inhibiting the phosphorylation of MAPK1 and ß-catenin. Finally, we confirmed that miR-543 represses migration, EMT and inhibits levels of ECM proteins in TGF-ß-treated ESCs by targeting the Wnt/ß-catenin signaling pathway. Our results demonstrated that miR-543 suppresses migration and EMT of TGF-ß-treated ESCs by targeting the MAPK and Wnt/ß-catenin pathways.

Phase 2 study of anastrozole in patients with estrogen receptor/progesterone receptor positive recurrent low-grade endometrial stromal sarcomas: The PARAGON trial (ANZGOG 0903).

BACKGROUND: Aromatase inhibitors are standard of care for low-grade endometrial stromal sarcomas (LGESS), based on very high response rates reported in retrospective studies. We evaluated the activity of anastrozole in recurrent/metastatic LGESS patients enrolled in PARAGON, a basket trial of anastrozole in estrogen receptor (ER±)/progesterone receptor (PR+) gynecological cancers. METHOD: An investigator-initiated, single-arm, prospective open-label trial of anastrozole 1 mg/day in patients with ER ± PR + ve LGESS with measurable disease, treated until progressive disease or unacceptable toxicity. Primary endpoint was clinical benefit (complete/partial response + stable disease) rate (CBR) at 3 months. Secondary endpoints include progression-free survival (PFS), quality of life and toxicity. RESULTS: 15 eligible patients were enrolled. CBR at 3 months was 73% (95% CI: 48-89.1%); unchanged at 6 months. Best response was 26.7%, including complete response in one (6.7%; 95% CI 1.2-29.8%), partial response in three (20%, 95% CI 7.1-45.2%) and stable disease in seven (46.7%). Four patients ceased treatment by 3 months due to progression. Median PFS was not reached (25th percentile: 2.9 months (95% CI: 1.2-NR)). PFS was 73.3%, 73.3% and 66% at 6, 12, and 18 months, respectively. Six patients remained on treatment for an average of 44.2 months (range 34.5-63.6) up until data cut. Toxicity was as expected, with 3 patients stopping due to adverse effects. CONCLUSION: The 26.7% objective response rate with anastrozole is lower than reported in retrospective series, but the CBR was high and durable. The results underscore the importance of prospective trials in rare cancers.

Retroperitoneal low grade endometrial stromal sarcoma with florid endometrioid glandular differentiation: Cytologic-histologic correlation and differential diagnosis.

Low grade endometrial stromal sarcoma (LGESS) is a rare neoplasm that typically arises in the uterine corpus and accounts for less than 1% of uterine sarcomas. Infrequently, extra-uterine LGESS can occur. Histologically, LGESS is characterized by a monotonous population of cells that resemble the proliferative phase of endometrial stroma and in their classic form they exhibit tongue-like growth pattern of infiltration and/or lymphovascular invasion. Infrequently LGESS can demonstrate various morphologic differentiation patterns, including endometrioid-type glands. We report the first fine needle aspiration (FNA) case of a periduodenal mass that was incidentally discovered on Computed Tomography (CT) scan of a 60-year-old female. The cytomorphologic and histologic findings and the immunohistochemical staining were consistent with a LGESS with endometrioid glandular differentiation. We are presenting the correlation between the cytologic, radiologic and pathologic features.

Endometrial Stromal Sarcoma Arising from Endometrial Polyp: A Case Report.

Endometrial stromal sarcoma (ESS) is a rare malignant tumor of the uterus. We report an uncommon case of ESS composed of both low-grade ESS and high-grade ESS arising from an endometrial polyp. On the findings of magnetic resonance imaging and contrast computed tomography, a patient was suspected of having uterine malignant tumor. She underwent a total abdominal hysterectomy with bilateral salpingo-oophorectomy. Macroscopically, the tumor was a polypoid lesion in the uterine cavity. The tumor was an endometrial polyp with ESS components. ESS was composed of low-grade ESS and high-grade ESS. By immunohistochemistry, both an endometrial polyp and low-grade ESS showed a positivity for CD10, estrogen receptor (ER), and progesterone receptor (PR). However, high-grade ESS showed only a focal and weak CD10 positivity with no immunostaining for ER and PR. A focal or diffuse positivity for α-smooth muscle actin and desmin was noted in both low-grade and high-grade ESS. The positive rates of Ki-67 and p53 in high-grade ESS were elevated up to over 95%. She was diagnosed as having ESS in a stage IA. After surgery, she received no further treatment. She has been without recurrence for 4 years since an initial surgery. In conclusion, immunohistochemical analyses are useful for make an accurate diagnosis of ESS showing a transition from low-grade ESS to high-grade ESS in addition to the conventional method.

Retinoic acid regulates endometriotic stromal cell growth through upregulation of Beclin1.

PURPOSE: To elucidate the role of retinoic acid (RA) in autophagy-mediated endometriosis. METHODS: The mRNA and protein expressions of autophagy markers were examined in Ishikawa cells and endometriotic stromal cells (ESCs) after RA treatment. Beclin1 expression was specifically analyzed in clinical samples of endometriosis. The effect of Beclin1 knockdown on ESC growth was assessed, and the effect of autophagy inhibition on the sensitivity of endometriotic cells to RA was analyzed. RESULTS: RA treatment enhanced the autophagy in ESCs, and Beclin1 expression showed a negative correlation with the clinical stage of endometriosis. Beclin1 knockdown enhanced ESC growth, whereas RA treatment reversed this effect. Furthermore, inhibition of autophagy by chloroquine (CQ) and Beclin1 knockdown did not show any positive effect on the sensitivity of endometriotic cells to RA. CONCLUSIONS: RA treatment induces autophagy and Beclin1 may play an important role in endometriosis progression.

Silencing nc886, a Non-Coding RNA, Induces Apoptosis of Human Endometrial Cancer Cells-1A In Vitro.

BACKGROUND The role that nc886, a non-coding microRNA, plays in human endometrial cancer is unknown. The present study aimed to describe the functional role of nc886 in human endometrial cancer-1A (HEC-1A) cell line, which may provide another target for human endometrial cancer treatment. MATERIAL AND METHODS The expression levels of nv886 in normal human endometrial tissue and the early phase and late phase of human endometrial cancer tissues were determined and compared by fluorescence in situ hybridization (FISH). Small interference RNA (siRNA) was used to inhibit nc886, and cell proliferation was evaluated with the MTT test. mRNA levels of PKR, NF-κB, vascular endothelial growth factor (VEGF), and caspase-3 were determined against glyceraldehyde 3-phosphate dehydrogenase (GAPDH between the HEC-1A control group and the silenced group (nc886 silenced with siRNA) by real-time reverse transcription polymerase chain reaction (RT-PCR). The protein levels of PKR (total and phosphorylated form), NF-κB, VEGF, and caspase-3 were determined against GAPDH by Western blotting, and cell apoptosis was determined by flow cytometry. RESULTS Our results indicated that a higher level of nc886 was expressed in the late phase of human endometrial cancer tissue, less than in the early phase but still higher than in normal human endometrial tissue. After nc886 was silenced, protein levels of p-PKR (phosphorylated PKR) and caspase-3 were increased, whereas NF-κB and VEGF were decreased. CONCLUSIONS The rate of apoptosis in the silenced group was increased and the rate of cell proliferation was slower in comparison to the control.

Mixed endometrial stromal and smooth muscle tumor of the uterus in a postmenopausal woman: morphologic and immunohistochemical features.

Mixed endometrial stromal and smooth muscle tumor of the uterus is a rare occurrence, and it is truly challenging to diagnose or dif- ferentiate mesenchymal tumors of the uterine corpus, due to their many overlapping features. In most cases, the gross pathology of mixed endometrial stromal and smooth muscle tumor differs from that of pure endometrial stromal and pure smooth muscle tumors. A 59-year-old postmenopausal woman presented with vaginal spotting, low abdominal pain, and an uterine mass. Subsequent pelvic magnetic resonance imaging revealed a 4.0x3.8x3.4-cm sized uterine mass with enhancement. The mass showed restricted diffusion on diffusion-weighted images, and thus, was suspected to be uterine sarcoma rather than degenerative leiomyoma. Levels of tumor markers, CA 125, CA 19-9, and SCC, were within their normal ranges. The patient underwent exploratory laparotomy. Morphological and immunohistochemical evaluations were performed, and a final diagnosis of mixed endometrial stromal and smooth muscle tumor of the uterus was rendered. Her postoperative course was uneventful, and aromatase inhibitor adjuvant therapy was administered.

"Pseudomyxoma Endometrii": Endometrial Deposition of Acellular Mucin from a Low-Grade Appendiceal Mucinous Neoplasm as a Rare Mimic of Myxoid Uterine Tumors.

Low-grade appendiceal mucinous neoplasms (LAMNs) are commonly associated with deposition of mucin, with or without admixed low-grade epithelium, on peritoneal surfaces (pseudomyxoma peritonei). We describe a very rare presentation of LAMN as extensive mucin deposition in the endometrium of a 43-yr-old woman initially mistaken for a primary uterine myxoid neoplasm. The patient underwent endometrial curettage that demonstrated abundant myxoid/mucoid material interspersed with small vessels, bland eosinophilic spindled cells, scattered foci of typical endometrial stroma, and occasional endometrioid glands. The endometrial stroma was positive for CD10, and the eosinophilic spindled cells were positive for actin. The lesion was interpreted as "myxoid/mucinous neoplasm, most likely of smooth muscle/endometrial stromal origin." Subsequent laparotomy revealed peritoneal mucin in the anterior cul-de-sac and a dilated appendix. Pathologic review confirmed appendiceal LAMN and multifocal peritoneal mucinosis. The uterus contained scant residual mucoid material. On review of all pathologic material at our institution, the endometrial lesion was consistent with organizing mucin derived from the LAMN with entrapped benign endometrium. "Pseudomyxoma endometrii" is readily mistaken for a primary uterine myxoid neoplasm, particularly myxoid endometrial stromal tumor. A key to diagnosis is recognition that the material is mucin rather than myxoid stroma. This is evidenced by the absence of embedded stromal cells and presence of myofibroblastic, vascular, and macrophage infiltration associated with organization. Epithelium containing goblet cells is an important clue if present. The presence of rare endometrial glands within the endometrial stroma suggests that the latter is entrapped rather than neoplastic.

Molecular mechanisms of endometrial stromal sarcoma and undifferentiated endometrial sarcoma as premises for new therapeutic strategies.

Endometrial stromal sarcoma (ESS) and undifferentiated endometrial sarcoma (UES) are very rare gynecologic malignancies. Due to the rarity and heterogeneity of these tumors, little is known about their epidemiology, pathogenesis, and molecular pathology. Our previous studies have described deregulation of histone deacetylases expression in ESS/UES samples. Some of these enzymes can be inhibited by substances which are already approved for treatment of cutaneous T-cell lymphoma. On the basis of published data, they may also provide a therapeutic option for ESS/UES patients. Our review focuses on molecular mechanisms of ESS/UES. It describes various aspects with special emphasis on alteration of histone deacetylation and its possible relevance for novel therapies.

Cellular mesenchymal tumors of the uterus: a review emphasizing recent observations.

Cellular mesenchymal tumors of the uterus may be divided in 2 main groups, smooth muscle and endometrial stromal. Among the former, highly cellular leiomyoma is the classic example. This tumor is not infrequently confused with an endometrial stromal tumor due to its often yellow color and soft consistency, dense cellularity, striking vascularity, not uncommon irregular margin and even rarely association with seedling cellular leiomyomas, both mimicking the infiltration of a low-grade endometrial stromal sarcoma. Cellular intravenous leiomyomatosis can also mimic endometrial stromal sarcoma due to their shared intravascular growth. A variety of histologic features typical of cellular smooth muscle including clefts and differing vasculature help in this distinction. Although endometrial stromal tumors are typically highly cellular, recent studies have expanded their spectrum to include those that are less so due to smooth muscle metaplasia, fibrous and myxoid change, and even oxyphilic cytoplasm. A subset now designated high-grade endometrial stromal sarcoma showing a t(10;17) has been characterized to show small epithelioid cells associated with brisk miotic activity, typically being CD10, ER and PR negative, and cyclin D1 positive. These tumors are juxtaposed to areas of fibromyxoid endometrial stromal neoplasia in 50% of cases. An enigmatic category of uterine mesenchymal neoplasms, often densely cellular, are those descriptively referred to as "uterine tumors resembling ovarian sex cord tumors." Their spectrum is briefly noted as is their crucial distinction from stromal sarcoma with sex cord-like differentiation. Other tumors that rarely occur in the uterus that are densely cellular include but are not limited to undifferentiated uterine sarcoma, embryonal rhabdomyosarcoma, primitive neuroectodermal tumor, lymphoma or small cell, or undifferentiated carcinoma. In this essay, I review the most helpful morphologic, immunohistochemical, and/or cytogenetic features in the diagnosis of each one of these entities.

Endometrial stromal sarcoma: clinicopathological and immunophenotypic study of 16 cases.

PURPOSE: Endometrial stromal sarcomas (ESSs) are rare tumors and are divided into two groups: low-grade endometrial stromal sarcoma (ESS-LG) and undifferentiated endometrial sarcoma (UES). The purpose of this study was to compare the clinicopathological features and immunophenotypes of ESS-LG and UES. METHODS: The authors evaluated 16 patients diagnosed with ESS at the Hyogo Cancer Center, reviewed their files and data, and performed an immunohistochemical study for oncogenic proteins (EGFR, PDGFR-α, and PDGFR-ß) and cell cycle regulators (cyclin D1, cyclin E, p16(INK4a), p21(cip1), p27(kip1), and p53) to compare ESS-LG and UES using the World Health Organization (WHO) classification. RESULTS: Four cases (25 %) were classified as ESS-LGs and 12 (75 %) as UES. Patients with UES had a significantly worse overall survival than did those with ESS-LG (p = 0.0445). Although no ESS-LGs showed expression of p16(INK4a), 10 of 12 (83 %) UESs showed expression of p16(INK4a). UESs showed a trend toward higher expression of cyclin D1, p21(cip1), and p53 compared with ESS-LGs. CONCLUSIONS: Our data emphasize the clinical importance of the WHO classification of ESS. It is of utmost importance to establish a proper classification to increase the consistency of data that may be useful for improving clinical and therapeutic management of patients with ESS.

Recent developments in uterine mesenchymal neoplasms.

Smooth muscle and endometrial stromal tumours represent the two most common uterine mesenchymal neoplasms that may present diagnostic dilemmas for the practising surgical pathologist. Recent changes in morphological and staging criteria, as well as the discovery of new immunohistochemical markers, have improved the diagnosis and classification of these tumours. We highlight the difficulty in distinguishing tumour cell necrosis from infarct-type necrosis and the limited utility of p16 immunohistochemical expression in the diagnosis of leiomyosarcoma. We also discuss the controversial use of mitotic activity and necrosis as prognostic factors in endometrial stromal sarcomas. Emerging genetic information has also greatly expanded our understanding of 'sarcomagenesis' in both tumour types and may provide insight into potential therapeutic targets for the treatment of leiomyosarcoma and endometrial stromal sarcomas, harboring MED12 (mediator complex subunit 12) mutations and recurrent gene rearrangements, respectively. In this review, we discuss the core updates in the diagnosis and classification of uterine leiomyosarcomas and endometrial stromal sarcomas, highlighting new and important molecular genetic findings that may drive pathogenesis.

Gene expression signatures differentiate uterine endometrial stromal sarcoma from leiomyosarcoma.

OBJECTIVE: Endometrial stromal sarcoma (ESS) and leiomyosarcoma (LMS) are the two most common uterine sarcomas, but both are rare tumors. The aim of the present study was to compare the global gene expression patterns of ESS and LMS. METHODS: Gene expression profiles of 7 ESS and 13 LMS were analyzed using the HumanRef-8 BeadChip from Illumina. Differentially expressed candidate genes were validated using quantitative real-time PCR and immunohistochemistry. RESULTS: Unsupervised hierarchical clustering using all 54,675 genes in the array separated ESS from LMS samples. We identified 549 unique probes that were significantly differentially expressed in the two malignancies by greater than 2-fold with 1% FDR cutoff using one-way ANOVA with Benjamini-Hochberg correction, of which 336 and 213 were overexpressed in ESS and LMS, respectively. Genes overexpressed in ESS included SLC7A10, EFNB3, CCND2, ECEL1, ITM2A, NPW, PLAG1 and GCGR. Genes overexpressed in LMS included CDKN2A, FABP3, TAGLN, JPH2, GEM, NAV2 and RAB23. The top 100 genes overexpressed in LMS included those coding for myosin light chain and caldesmon, but not the genes coding for desmin or actin. CD10 was not overexpressed in ESS. Results for selected genes were validated by quantitative real-time PCR and immunohistochemistry. CONCLUSIONS: We present the first study in which gene expression profiling was shown to distinguish between ESS and LMS. The molecular signatures unique to each of these malignancies may aid in expanding the diagnostic battery for their differentiation, and may provide a molecular basis for prognostic studies and therapeutic target discovery.

Identification of suitable reference genes for gene expression measurement in uterine sarcoma and carcinosarcoma tumors.

OBJECTIVE: To date no suitable reference genes have been identified in carcinosarcomas and non-epithelial malignant tumors of corpus uteri for normalizing real-time RT-PCR (qRT-PCR) assays. The purpose of this study was to select appropriate references for gene expression studies in these tumors. MATERIALS AND METHODS: We used RNA extracts from 75 tissue samples, representing 50 tumors and 25 fragments of normal uterine tissues obtained from 50 patients treated for mixed tumors, smooth muscle sarcoma and stromal sarcoma of the uterus. qRT-PCR for five potential reference (housekeeping) genes, namely B2M, HMBS, HPRT1, TBP and UBC, was performed. The expression stability of these genes was assayed using geNorm software application. RESULTS: The analysis of gene expression data with geNorm identified HPRT1 as the most stable reference gene, followed by UBC and HMBS, for all the investigated tissues. When stratified by disease, the results still pointed at HPRT1 as the gene that retained the greatest robustness in mixed tumors as well as in smooth muscle and stromal sarcomas. CONCLUSIONS: Our work is the first report on reference gene selection for qRT-PCR applications in mixed tumors, smooth muscle sarcoma and stromal sarcoma of the uterus. A ranking of candidate genes' stability values for the three types of tumors is provided and might serve as a valuable guide for future gene expression studies of these rare entities.

Cytogenetic and molecular aberrations in endometrial stromal tumors.

Endometrial stromal tumors (ESTs) are rare uterine mesenchymal tumors, comprising <10% of all uterine mesenchymal neoplasms. The latest World Health Organization classification divides endometrial stromal tumors into 3 categories based on morphologic features: endometrial stromal nodule (ESN), low-grade endometrial stromal sarcoma, and undifferentiated endometrial sarcoma. Specific cytogenetic aberrations and molecular genetic alterations have recently been identified in endometrial stromal tumors, providing insights into their molecular biology, potential diagnostic markers, and possible therapeutic targets. Currently, recurrent chromosomal rearrangements resulting in gene fusion play a substantive role in the pathogenesis of endometrial stromal nodules, endometrial stromal sarcomas, and a small subset of undifferentiated endometrial sarcomas. Loss of heterozygosity of tumor suppressor genes and deregulation of the Wnt signaling pathway have also been implicated in EST tumorigenesis. In this review, we summarize the recent advances in the molecular pathology of endometrial stromal tumors.

Diverse phenotypic profile of uterine tumors resembling ovarian sex cord tumors: an immunohistochemical study of 12 cases.

BACKGROUND: Uterine tumors resembling ovarian sex cord tumors (UTROSCTs) are rare neoplasms thought to be of putative endometrial stromal origin and solely composed of sex cord elements. Our study aimed to delineate the immunophenotype of these tumors and to verify whether their morphology reflects true sex cord-like differentiation. DESIGN: Representative paraffin blocks from 12 UTROSCTs were selected after confirmation of the diagnosis. Cords and/or trabeculae were seen in all tumors, whereas tubules, diffuse areas, and a retiform pattern were present in 9, 6, and 2 cases, respectively. Tumors were stained for sex cord (inhibin, calretinin, WT1, and melan-A), epithelial (KL1 and epithelial membrane antigen), and smooth muscle markers (smooth muscle actin, desmin, smooth muscle myosin heavy chain, h-caldesmon, and histone deacetylase-8), CD10, HMB45, S100, and CD117. Intensity and percentage of staining were recorded. RESULTS: Six out of 12 tumors were positive for sex cord markers (inhibin 3 of 12, calretinin 4 of 12, WT1 4 of 12, and melan-A 3 of 11) with 4 tumors coexpressing more than one marker. Half of the UTROSCTs showed positivity for KL1, with 2 tumors coexpressing epithelial membrane antigen. All but one tumor expressed one or more smooth muscle markers, with smooth muscle actin, desmin and histone deacetylase-8 being most commonly expressed. CD10 was positive in 6 of 12 tumors, CD117 in 4 of 12, and S100 in 2 of 11 tumors, whereas HMB45 was negative in 11 tumors tested. CONCLUSIONS: UTROSCTs have a diverse immunohistochemical profile often coexpressing sex cord, epithelial, and smooth muscle markers. The expression of smooth muscle markers in these tumors does not imply a smooth muscle origin as endometrial and sex cord stromal tumors are not infrequently positive for these markers. Positivity for sex cord markers supports a true sex cord/steroid phenotype. Although the immunohistochemical profile of these tumors overlaps with that of endometrial stromal tumors with sex cord-like differentiation as well as ovarian sex cord stromal tumors, the origin of UTROSCT remains uncertain.