Oliveira, André M.

Background:Myoepithelioma of the soft tissues is a rare entity and little is known about how best to manage locally recurrent and high-grade disease. Here, we retrospectively examined outcomes of surgery, chemotherapy, and radiation therapy (RT) for treatment of low-grade and high-grade myoepithelioma of soft tissues.Methods:We reviewed 20 cases of myoepithelioma of soft tissues seen at Mayo Clinic between 1994 and 2014. The effect of histologic grade and therapies received on relapse and survival were assessed.Results:We identified 13 patients with low-grade disease and 7 patients with high-grade disease. We found that low-grade disease was frequently effectively managed with surgical resection alone, whereas high-grade disease frequently metastasized and was often fatal. The 5-year event-free survival was 88% (confidence interval, 46%-98%) for low-grade disease versus 36% (confidence interval, 7%-75%;P=0.04) for high-grade disease. The relapse rate in low-grade disease was 29% at 5 years versus 64% (P=0.04) in high-grade disease. No significant responses to chemotherapy were noted, however, excellent responses to perioperative RT were seen.Conclusions:Surgery continues as the primary modality of treatment for myoepithelioma of soft tissues. Our study did not show a clear benefit of chemotherapy in the metastatic disease setting, but supports the use of perioperative RT in the management of high-grade disease; further investigation is warranted.

Nodular fasciitis (NF) is a clonal self‐limited neoplastic proliferation characterized by rearrangements of the USP6 locus in most examples. To our knowledge well‐documented malignant behavior has never been previously observed in NF. In this report we present an unusual case of NF with classical histologic features that showed a protracted clinical course characterized by multiple recurrences and eventual metastatic behavior over a period of 10 years. Molecular analyses revealed the presence and amplification of the novel PPPR6‐USP6 gene fusion, which resulted in USP6 mRNA transcriptional upregulation. These findings further support the oncogenic role of the USP6 protease in mesenchymal neoplasia and expand the biologic potential of NF. © 2016 Wiley Periodicals, Inc.

Nodular fasciitis is a benign fibroblastic proliferation typically found in the subcutaneous tissue or superficial fascia of the extremities that is often confused for malignancy. These lesions rarely occur on the eyelids and ocular adnexa and are seldom analyzed by ophthalmic pathologists. USP6 gene rearrangement has been recently demonstrated in nodular fasciitis and this rearrangement may lead to the formation of a fusion gene MYH9-USP6 in some cases. Herein, the authors describe a 38-year-old woman with a 6-month history of a progressively enlarging mass beneath her right medial upper eyelid. Histopathologic analysis of the excisional biopsy confirmed classic features of nodular fasciitis. Molecular cytogenetic analysis revealed a rearrangement of the USP6 locus, confirming the diagnosis of benign nodular fasciitis.

Abstract Ewing sarcomas are aggressive, poorly differentiated pediatric tumors of bone and soft tissue. Ewing sarcoma affects one to three people per million every year and is the second most common pediatric bone malignancy after osteosarcoma. Approximately 85% of Ewing sarcomas harbor the EWS-FLI fusion protein, which arises from a chromosomal translocation, t(11:22)(q24:q12). EWS-FLI interacts with numerous lineage-essential transcription factors to maintain mesenchymal progenitors in an undifferentiated state. We previously showed that EWS-FLI binds the osteogenic transcription factor RUNX2, and prevents osteoblast differentiation. RUNX3 is highly homologous to RUNX2 and participates in the mesenchymal-derived bone formation. RUNX3 has been described as both a tumor suppressor and an oncogene in different tumor types. In this study, we investigated the role of RUNX3 in Ewing Sarcoma. RUNX3 was detected in all Ewing sarcoma cells examined (7/7 cell lines, and 4/4 primary tumors), whereas RUNX2 was detected in only 73% of these specimens. Immunoprecipitation experiments revealed that RUNX3 binds to EWS-FLI via its Runt domain, which is >91% identical to the Runt domain in RUNX2. The interaction between RUNX3 and EWS-FLI in cell nuclei was confirmed by immunofluorescence. Moreover, EWS-FLI interactions prevented RUNX3 from activating the transcription of a RUNX-responsive reporter, p6OSE2. To determine the role of RUNX3 in Ewing sarcoma cell growth, we stably suppressed RUNX3 expression in the Ewing sarcoma cell line A673 with shRNAs. In anchorage independent growth assays in soft agar, RUNX3-deficient A673 cells formed smaller colonies than cells expressing scrambled shRNAs. Consistent with the smaller colonies, RUNX3 suppressed cells had increased expression of the cyclin dependent kinase inhibitor p21. Taken together, these results suggest and oncogenic role for RUNX3 in Ewing sarcoma. Citation Format: Krista L. Bledsoe, Meghan E. McGee-Lawrence, Emily T. Camilleri, Andre M. Oliveira, Andre J. van Wijnen, Jennifer J. Westendorf. RUNX3 plays an oncogenic role in Ewing sarcoma cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1413. doi:10.1158/1538-7445.AM2014-1413

AimsEpithelioid haemangioendothelioma (EHE) is a malignant vascular neoplasm. Subsets have been characterized previously by translocations resulting in either WWTR1–CAMTA1 or YAP1–TFE3 fusion. We sought to develop molecular and immunohistochemical (IHC) assays to aid in the diagnosis and characterization of EHE.Methods and resultsFifty‐two formalin‐fixed, paraffin‐embedded (FFPE) cases diagnosed between 2002 and 2014 were retrieved from the pathology files of our institutions. Reverse transcription–polymerase chain reaction (RT–PCR) assays were optimized to detect WWTR1–CAMTA1 and YAP1–TFE3 fusion transcripts in FFPE tissue and transcription factor E3 (TFE3) protein accumulation was examined by immunohistochemistry (IHC). RNA was extracted from 33 adequate samples, with more recent cases providing a greater yield of high quality RNA. Fourteen of 18 informative cases were positive for WWTR1–CAMTA1 fusion transcripts, four of which showed higher‐grade cytological features termed by some as ‘malignant EHE’. Novel in‐frame fusion transcripts were identified in four cases by direct sequencing. IHC revealed variable nuclear TFE3 staining in six of 17 cases; three with patchy staining showed WWTR1–CAMTA1 fusion. One of 18 informative cases was positive for YAP1–TFE3 fusion and showed strong nuclear TFE3 staining by IHC.ConclusionsThis study confirms the high incidence of WWTR1–CAMTA1 and YAP1–TFE3 rearrangements in EHE and indicates that the staining pattern for TFE3 IHC is critical for specificity.

Ewing sarcoma is an aggressive pediatric small round cell tumor that predominantly occurs in bone. Approximately 85% of Ewing sarcomas harbor the EWS/FLI fusion protein, which arises from a chromosomal translocation, t(11:22)(q24:q12). EWS/FLI interacts with numerous lineage‐essential transcription factors to maintain mesenchymal progenitors in an undifferentiated state. We previously showed that EWS/FLI binds the osteogenic transcription factor RUNX2 and prevents osteoblast differentiation. In this study, we investigated the role of another Runt‐domain protein, RUNX3, in Ewing sarcoma. RUNX3 participates in mesenchymal‐derived bone formation and is a context dependent tumor suppressor and oncogene. RUNX3 was detected in all Ewing sarcoma cells examined, whereas RUNX2 was detected in only 73% of specimens. Like RUNX2, RUNX3 binds to EWS/FLI via its Runt domain. EWS/FLI prevented RUNX3 from activating the transcription of a RUNX‐responsive reporter, p6OSE2. Stable suppression of RUNX3 expression in the Ewing sarcoma cell line A673 delayed colony growth in anchorage independent soft agar assays and reversed expression of EWS/FLI‐responsive genes. These results demonstrate an important role for RUNX3 in Ewing sarcoma. J. Cell. Physiol. 229: 2049–2056, 2014. © 2014 Wiley Periodicals, Inc.

Osteomalacia has multiple aetiologies including the least common, tumour-induced osteomalacia (TIO). Recently, most cases of TIO have been confirmed to be due to phosphaturic mesenchymal tumour of mixed connective tissue type (PMTMCT). Most cases of TIO are the result of production of the fibroblast growth factor-23 (FGF-23) by the tumour. The authors recently showed reverse transcriptase PCR (RT-PCR) for FGF-23 to be valuable in the diagnosis of PMTMCT. However, the authors also noted FGF-23 expression in some cases of aneurysmal bone cyst (ABC) and chondromyxoid fibroma (CMF). For the present study, the authors studied FGF-23 expression by RT-PCR in 19 cases of ABC and eight cases of CMF, all with typical clinical and radiographic features and without evidence of TIO. Seven of 16 (44%) ABC and two of seven (29%) CMF were positive for FGF-23. These results confirm that ABC and CMF not uncommonly express FGF-23. These results strongly suggest caution and careful integration with all other clinical and radiographic data in the use of FGF-23 RT-PCR for the diagnosis of PMTMCT.

A newly identified gene fusion defines the vascular cancer epithelioid hemangioendothelioma and encodes a chimeric transcription factor.