RESUMO
Epithelioid sarcoma is a rare and aggressive mesenchymal tumour, the genetic hallmark of which is the loss of expression of SMARCB1, a key member of the SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodelling complex. Hampered by its rarity, epithelioid sarcoma has received little research attention and therapeutic options for this disease remain limited. SMARCB1-deficient tumours also include malignant rhabdoid tumour, atypical teratoid and rhabdoid tumour, epithelioid malignant peripheral nerve sheath tumour, and poorly differentiated chordoma. Histologically, it can be challenging to distinguish epithelioid sarcoma from malignant rhabdoid tumour and other SMARCB1-deficient tumours, whereas methylation profiling shows that they represent distinct entities and facilitates their classification. Methylation studies on SMARCB1-deficient tumours, although not including epithelioid sarcomas, reported methylation subgroups which resulted in new clinical stratification and therapeutic approaches. In addition, emerging evidence indicates that immunotherapy, including immune checkpoint inhibitors, represents a promising therapeutic strategy for SMARCB1-deficient tumours. Here, we show that some epithelioid sarcomas share methylation patterns of malignant rhabdoid tumours indicating that this could help to distinguish these entities and guide treatment. Using gene expression data, we also showed that the immune environment of epithelioid sarcoma is characterised by a predominance of CD8+ lymphocytes and M2 macrophages. These findings have potential implications for the management of patients with epithelioid sarcoma. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
Assuntos
Tumor Rabdoide , Sarcoma , Humanos , Proteínas de Ligação a DNA/genética , Proteínas Cromossômicas não Histona/genética , Tumor Rabdoide/genética , Tumor Rabdoide/terapia , Tumor Rabdoide/metabolismo , Imuno-Histoquímica , Proteína SMARCB1/genética , Sarcoma/genética , Sarcoma/terapia , Sarcoma/metabolismoRESUMO
The FOS gene family has been implicated in tumourigenesis across several tumour types, particularly mesenchymal tumours. The rare fibrous tumour desmoplastic fibroblastoma is characterised by overexpression of FOSL1. However, previous studies using cytogenetic and molecular techniques did not identify an underlying somatic change involving the FOSL1 gene to explain this finding. Prompted by an unusual index case, we report the discovery of a novel FOSL1 rearrangement in desmoplastic fibroblastoma using whole-genome and targeted RNA sequencing. We investigated 15 desmoplastic fibroblastomas and 15 fibromas of tendon sheath using immunohistochemistry, in situ hybridisation and targeted RNA sequencing. Rearrangements in FOSL1 and FOS were identified in 10/15 and 2/15 desmoplastic fibroblastomas respectively, which mirrors the pattern of FOS rearrangements observed in benign bone and vascular tumours. Fibroma of tendon sheath, which shares histological features with desmoplastic fibroblastoma, harboured USP6 rearrangements in 9/15 cases and did not demonstrate rearrangements in any of the four FOS genes. The overall concordance between FOSL1 immunohistochemistry and RNA sequencing results was 90%. These findings illustrate that FOSL1 and FOS rearrangements are a recurrent event in desmoplastic fibroblastoma, establishing this finding as a useful diagnostic adjunct and expanding the spectrum of tumours driven by FOS gene family alterations. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
Assuntos
Fibroma Desmoplásico , Fibroma , Neoplasias de Tecidos Moles , Humanos , Fibroma Desmoplásico/diagnóstico , Fibroma Desmoplásico/genética , Fibroma Desmoplásico/patologia , Fibroma/genética , Rearranjo Gênico , Hibridização In Situ , Neoplasias de Tecidos Moles/genética , Neoplasias de Tecidos Moles/patologia , Ubiquitina Tiolesterase/genéticaRESUMO
Superficial CD34-positive fibroblastic tumor (SCD34FT) is a recently recognized soft tissue tumor that is considered to be of borderline malignancy. The pathogenesis of this tumor remains incompletely understood, but it has been suggested that SCD34FT overlaps with tumors showing fusions involving the PRDM10 gene. Previous analyses of PRDM10-rearranged tumors have demonstrated that they have a distinct gene expression profile, resulting in high expression of CADM3 (also known as SynCam3), which can be detected immunohistochemically. Here, we investigated a series (n = 43) of SCD34FT or PRDM10-rearranged tumors and potential mimics (n = 226) with regard to morphological, genetic, and immunohistochemical features. The results show that SCD34FT and PRDM10-rearranged tumor are morphologically indistinguishable; 41 of 43 tumors of both entities are CADM3-positive. Hence, we suggest that they constitute a single entity, preferably referred to as SCD34FT. Expression of CADM3 was only rarely seen in other soft tissue tumors, except in tumors with Schwann cell differentiation. Thus, IHC for CADM3, in combination with the characteristic morphological features, is a valuable adjunct in the diagnosis of SCD34FT.
Assuntos
Biomarcadores Tumorais , Neoplasias de Tecidos Moles , Biomarcadores Tumorais/análise , Proteínas de Ligação a DNA/genética , Humanos , Neoplasias de Tecidos Moles/patologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , TranscriptomaRESUMO
Diagnosing MPNST can be challenging, but genetic alterations recently identified in polycomb repressive complex 2 (PRC2) core component genes, EED and SUZ12, resulting in global loss of the histone 3 lysine 27 trimethylation (H3K27me3) epigenetic mark, represent drivers of malignancy and a valuable diagnostic tool. However, the reported loss of H3K27me3 expression ranges from 35% to 84%. We show that advances in molecular pathology now allow many MPNST mimics to be classified confidently. We confirm that MPNSTs harbouring mutations in PRC2 core components are associated with loss of H3K27me3 expression; whole-genome doubling was detected in 68%, and SSTR2 was amplified in 32% of MPNSTs. We demonstrate that loss of H3K27me3 expression occurs overall in 38% of MPNSTs, but is lost in 76% of histologically classical cases, whereas loss was detected in only 23% cases with heterologous elements and 14% where the diagnosis could not be provided on morphology alone. H3K27me3 loss is rarely seen in other high-grade sarcomas and was not found to be associated with an inferior outcome in MPNST. We show that DNA methylation profiling distinguishes MPNST from its histological mimics, was unrelated to anatomical site, and formed two main clusters, MeGroups 4 and 5. MeGroup 4 represents classical MPNSTs lacking H3K27me3 expression in the majority of cases, whereas MeGroup 5 comprises MPNSTs exhibiting non-classical histology and expressing H3K27me3 and cluster with undifferentiated sarcomas. The two MeGroups are distinguished by differentially methylated PRC2-associated genes, the majority of which are hypermethylated in the promoter regions in MeGroup 4, indicating that the PRC2 target genes are not expressed in these tumours. The methylation profiles of MPNSTs with retention of H3K27me3 in MeGroups 4 and 5 are independent of mutations in PRC2 core components and the driver(s) in these groups remain to be identified. Our results open new avenues of investigation. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.
Assuntos
Histonas/metabolismo , Neurofibrossarcoma/diagnóstico , Neurofibrossarcoma/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Metilação de DNA , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neurofibrossarcoma/classificação , Adulto JovemRESUMO
The rare benign giant cell tumour of bone (GCTB) is defined by an almost unique mutation in the H3.3 family of histone genes H3-3A or H3-3B; however, the same mutation is occasionally found in primary malignant bone tumours which share many features with the benign variant. Moreover, lung metastases can occur despite the absence of malignant histological features in either the primary or metastatic lesions. Herein we investigated the genetic events of 17 GCTBs including benign and malignant variants and the methylation profiles of 122 bone tumour samples including GCTBs. Benign GCTBs possessed few somatic alterations and no other known drivers besides the H3.3 mutation, whereas all malignant tumours harboured at least one additional driver mutation and exhibited genomic features resembling osteosarcomas, including high mutational burden, additional driver event(s), and a high degree of aneuploidy. The H3.3 mutation was found to predate the development of aneuploidy. In contrast to osteosarcomas, malignant H3.3-mutated tumours were enriched for a variety of alterations involving TERT, other than amplification, suggesting telomere dysfunction in the transformation of benign to malignant GCTB. DNA sequencing of the benign metastasising GCTB revealed no additional driver alterations; polyclonal seeding in the lung was identified, implying that the metastatic lesions represent an embolic event. Unsupervised clustering of DNA methylation profiles revealed that malignant H3.3-mutated tumours are distinct from their benign counterpart, and other bone tumours. Differential methylation analysis identified CCND1, encoding cyclin D1, as a plausible cancer driver gene in these tumours because hypermethylation of the CCND1 promoter was specific for GCTBs. We report here the genomic and methylation patterns underlying the rare clinical phenomena of benign metastasising and malignant transformation of GCTB and show how the combination of genomic and epigenomic findings could potentially distinguish benign from malignant GCTBs, thereby predicting aggressive behaviour in challenging diagnostic cases. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.
Assuntos
Neoplasias Ósseas/genética , Transformação Celular Neoplásica/genética , Metilação de DNA , Tumor de Células Gigantes do Osso/genética , Mutação , Neoplasias Ósseas/patologia , Transformação Celular Neoplásica/patologia , Tumor de Células Gigantes do Osso/patologia , Humanos , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Sequenciamento Completo do GenomaRESUMO
EWSR1-SMAD3 fibroblastic tumour is a recently described soft tissue lesion. To date, eight cases have been reported, all sited in superficial soft tissue, typically occurring in the hands and feet with a tendency for local recurrence if incompletely excised. No metastatic spread has been reported, and hence, these tumours are currently considered benign. Herein, we present the radiological and histological features of the first reported occurrence of this entity in bone: a 44-year-old man with a tumour in the right tibia, treated with en bloc resection and showing no signs of relapse at 7 years. This tumour should be added to the differential diagnosis of bone lesions which harbour EWSR1 gene rearrangement.
Assuntos
Proteínas de Ligação a Calmodulina , Proteínas de Ligação a RNA , Adulto , Proteínas de Ligação a Calmodulina/genética , Humanos , Masculino , Proteína EWS de Ligação a RNA/genética , Proteína Smad3RESUMO
OBJECTIVE: To describe the MRI features of paediatric conventional central chondrosarcoma (CC-CS) and correlate with histological grade. MATERIALS AND METHODS: A retrospective review of children/adolescents with histologically confirmed CC-CS. Data collected included age, sex, skeletal location, and histology from needle biopsy or resection, which was classified as atypical cartilaginous tumours/grade 1 CS (ACT/Gd 1 CS), high-grade chondrosarcoma (HGCS), and dedifferentiated chondrosarcoma (DD-CS). MRI studies were reviewed independently by 2 radiologists blinded to the histology grade, who graded the tumours as ACT/Gd 1 CS, HGCS, and DD-CS based on MRI features. RESULTS: The study included 7 males and 10 females with mean age 13.9 years (range 6-18 years). Tumours were located in the femur (n = 6), humerus (n = 3), tibia, ilium, scapula, and ulna (n = 1 each), and the small bones of the hands or feet (n = 4). Final histology grade was ACT/Gd 1 CS in 15 cases and HGCS in 2 (both grade 1 CS with focal transition to grade 2), 15 based on surgical specimens, 1 based on open biopsy, and 1 on needle biopsy alone. Predicted MRI grade for the 2 readers was ACT/Gd 1 CS in 11 cases each and HGCS in 6 cases each, indicating a mismatch between predicted MRI grade and histological grade in 8 (47%) cases (4 cases with one reader mismatch and 4 cases with both). CONCLUSIONS: MRI findings in paediatric CC-CS may be misleading, showing features suggestive of HGCS 7 of 17 (41.2%) of cases. This should be taken into consideration when planning surgical treatment.
Assuntos
Neoplasias Ósseas , Condrossarcoma , Adolescente , Neoplasias Ósseas/diagnóstico por imagem , Criança , Condrossarcoma/diagnóstico por imagem , Feminino , Humanos , Úmero , Imageamento por Ressonância Magnética , Masculino , Estudos RetrospectivosRESUMO
Non-ossifying fibroma (NOF), which occasionally results in pathologic fracture, is considered the most common benign and self-limiting lesion of the growing skeleton. By DNA sequencing we have identified hotspot KRAS, FGFR1 and NF1 mutations in 48 of 59 patients (81.4%) with NOF, at allele frequencies ranging from 0.04 to 0.61. Our findings define NOF as a genetically driven neoplasm caused in most cases by activated MAP-kinase signalling. Interestingly, this driving force either diminishes over time or at least is not sufficient to prevent autonomous regression and resolution. Beyond its contribution to a better understanding of the molecular pathogenesis of NOF, this study adds another benign lesion to the spectrum of KRAS- and MAP-kinase signalling-driven tumours. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Assuntos
Neoplasias Ósseas/genética , Fibroma/genética , Sistema de Sinalização das MAP Quinases/genética , Mutação , Adolescente , Neoplasias Ósseas/patologia , Análise Mutacional de DNA/métodos , Feminino , Fibroma/patologia , Predisposição Genética para Doença , Humanos , Masculino , Neurofibromina 1/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Sequenciamento do Exoma/métodos , Adulto JovemRESUMO
A fusion between fibronectin 1 (FN1) and activin receptor 2A (ACVR2A) has been reported previously in isolated cases of the synovial chondromatosis. To analyze further and validate the findings, we performed FISH and demonstrated recurrent FN1-ACVR2A rearrangements in synovial chondromatosis (57%), and chondrosarcoma secondary to synovial chondromatosis (75%), showing that FN1 and/or AVCR2A gene rearrangements do not distinguish between benign and malignant synovial chondromatosis. RNA sequencing revealed the presence of the FN1-ACVR2A fusion in several cases that were negative by FISH suggesting that the true prevalence of this fusion is potentially higher than 57%. In soft tissue chondromas, FN1 alterations were detected by FISH in 50% of cases but no ACVR2A alterations were identified. RNA sequencing identified a fusion involving FN1 and fibroblast growth factor receptor 2 (FGFR2) in the case of soft tissue chondroma and FISH confirmed recurrent involvement of both FGFR1 and FGFR2. These fusions were present in a subset of soft tissue chondromas characterized by grungy calcification, a feature reminiscent of phosphaturic mesenchymal tumor. However, unlike the latter, fibroblast growth factor 23 (FGF23) mRNA expression was not elevated in soft tissue chondromas harboring the FN1-FGFR1 fusion. The mutual exclusivity of ACVR2A rearrangements observed in synovial chondromatosis and FGFR1/2 in soft tissue chondromas suggests these represent separate entities. There have been no reports of malignant soft tissue chondromas, therefore differentiating these lesions will potentially alter clinical management by allowing soft tissue chondromas to be managed more conservatively.
Assuntos
Receptores de Activinas Tipo II/genética , Condroma/genética , Condromatose Sinovial/genética , Fibronectinas/genética , Neoplasias de Tecidos Moles/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Fator de Crescimento de Fibroblastos 23 , Rearranjo Gênico , Humanos , Masculino , Pessoa de Meia-Idade , Fusão Oncogênica , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Adulto JovemRESUMO
Survival rates for osteosarcoma, the most common primary bone cancer, have changed little over the past three decades and are particularly low for patients with metastatic disease. We conducted a multi-institutional genome-wide association study (GWAS) to identify germline genetic variants associated with overall survival in 632 patients with osteosarcoma, including 523 patients of European ancestry and 109 from Brazil. We conducted a time-to-event analysis and estimated hazard ratios (HR) and 95% confidence intervals (CI) using Cox proportional hazards models, with and without adjustment for metastatic disease. The results were combined across the European and Brazilian case sets using a random-effects meta-analysis. The strongest association after meta-analysis was for rs3765555 at 9p24.1, which was inversely associated with overall survival (HR = 1.76; 95% CI 1.41-2.18, p = 4.84 × 10-7 ). After imputation across this region, the combined analysis identified two SNPs that reached genome-wide significance. The strongest single association was with rs55933544 (HR = 1.9; 95% CI 1.5-2.4; p = 1.3 × 10-8 ), which localizes to the GLDC gene, adjacent to the IL33 gene and was consistent across both the European and Brazilian case sets. Using publicly available data, the risk allele was associated with lower expression of IL33 and low expression of IL33 was associated with poor survival in an independent set of patients with osteosarcoma. In conclusion, we have identified the GLDC/IL33 locus on chromosome 9p24.1 as associated with overall survival in patients with osteosarcoma. Further studies are needed to confirm this association and shed light on the biological underpinnings of this susceptibility locus.
Assuntos
Neoplasias Ósseas/genética , Neoplasias Ósseas/mortalidade , Interleucina-33/genética , Osteossarcoma/genética , Osteossarcoma/mortalidade , Adulto , Alelos , Brasil , Feminino , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Modelos de Riscos Proporcionais , Taxa de Sobrevida , População Branca/genéticaRESUMO
Fibro-osseous pseudotumors of the digits (FOPD) is a rare self-limiting lesion composed of bland looking hypercellular fibrous tissue and bone. USP6 rearrangement is a consistent genetic finding in aneurysmal bone cyst, nodular fasciitis, myositis ossificans and giant cell lesions of small bones. We report herein the occurrence of USP6 rearrangement in fibro-osseous pseudotumors of the digits using fluorescence in situ hybridization analysis (FISH). Of the five patients included, three were female and two were male. The age ranged from 33 to 72â¯years (mean 48â¯years). Lesions arose in the palm (nâ¯=â¯2), thenar (nâ¯=â¯1), middle finger (nâ¯=â¯1) and great toe (nâ¯=â¯1). All patients underwent resection. Four cases (80%) harbored USP6 rearrangements showing that fibro-osseous pseudotumors of digits belongs to the spectrum of clonal transient neoplasms including aneurysmal bone cyst, nodular fasciitis, myositis ossificans and giant cell lesion of small bones.
Assuntos
Fasciite/genética , Dedos/patologia , Rearranjo Gênico , Proteínas Proto-Oncogênicas/genética , Neoplasias de Tecidos Moles/genética , Ubiquitina Tiolesterase/genética , Adulto , Idoso , Diagnóstico Diferencial , Fasciite/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias de Tecidos Moles/patologiaRESUMO
BACKGROUND: For many years, first-line treatment for locally advanced or metastatic soft-tissue sarcoma has been doxorubicin. This study compared gemcitabine and docetaxel versus doxorubicin as first-line treatment for advanced or metastatic soft-tissue sarcoma. METHODS: The GeDDiS trial was a randomised controlled phase 3 trial done in 24 UK hospitals and one Swiss Group for Clinical Cancer Research (SAKK) hospital. Eligible patients had histologically confirmed locally advanced or metastatic soft-tissue sarcoma of Trojani grade 2 or 3, disease progression before enrolment, and no previous chemotherapy for sarcoma or previous doxorubicin for any cancer. Patients were randomly assigned 1:1 to receive six cycles of intravenous doxorubicin 75 mg/m2 on day 1 every 3 weeks, or intravenous gemcitabine 675 mg/m2 on days 1 and 8 and intravenous docetaxel 75 mg/m2 on day 8 every 3 weeks. Treatment was assigned using a minimisation algorithm incorporating a random element. Randomisation was stratified by age (≤18 years vs >18 years) and histological subtype. The primary endpoint was the proportion of patients alive and progression free at 24 weeks in the intention-to-treat population. Adherence to treatment and toxicity were analysed in the safety population, consisting of all patients who received at least one dose of their randomised treatment. The trial was registered with the European Clinical Trials (EudraCT) database (no 2009-014907-29) and with the International Standard Randomised Controlled Trial registry (ISRCTN07742377), and is now closed to patient entry. FINDINGS: Between Dec 3, 2010, and Jan 20, 2014, 257 patients were enrolled and randomly assigned to the two treatment groups (129 to doxorubicin and 128 to gemcitabine and docetaxel). Median follow-up was 22 months (IQR 15·7-29·3). The proportion of patients alive and progression free at 24 weeks did not differ between those who received doxorubicin versus those who received gemcitabine and docetaxel (46·3% [95% CI 37·5-54·6] vs 46·4% [37·5-54·8]); median progression-free survival (23·3 weeks [95% CI 19·6-30·4] vs 23·7 weeks [18·1-20·0]; hazard ratio [HR] for progression-free survival 1·28, 95% CI 0·99-1·65, p=0·06). The most common grade 3 and 4 adverse events were neutropenia (32 [25%] of 128 patients who received doxorubicin and 25 [20%] of 126 patients who received gemcitabine and docetaxel), febrile neutropenia (26 [20%] and 15 [12%]), fatigue (eight [6%] and 17 [14%]), oral mucositis (18 [14%] and two [2%]), and pain (ten [8%] and 13 [10%]). The three most common serious adverse events, representing 111 (39%) of all 285 serious adverse events recorded, were febrile neutropenia (27 [17%] of 155 serious adverse events in patients who received doxorubicin and 15 [12%] of 130 serious adverse events in patients who received gemcitabine and docetaxel, fever (18 [12%] and 19 [15%]), and neutropenia (22 [14%] and ten [8%]). 154 (60%) of 257 patients died in the intention-to-treat population: 74 (57%) of 129 patients in the doxorubicin group and 80 (63%) of 128 in the gemcitabine and docetaxel group. No deaths were related to the treatment, but two deaths were due to a combination of disease progression and treatment. INTERPRETATION: Doxorubicin should remain the standard first-line treatment for most patients with advanced soft-tissue sarcoma. These results provide evidence for clinicians to consider with their patients when selecting first-line treatment for locally advanced or metastatic soft-tissue sarcoma. FUNDING: Cancer Research UK, Sarcoma UK, and Clinical Trial Unit Kantonsspital St Gallen.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Sarcoma/tratamento farmacológico , Sarcoma/patologia , Neoplasias de Tecidos Moles/tratamento farmacológico , Neoplasias de Tecidos Moles/patologia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Intervalos de Confiança , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Docetaxel , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Esquema de Medicação , Feminino , Humanos , Infusões Intravenosas , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Sarcoma/mortalidade , Neoplasias de Tecidos Moles/mortalidade , Análise de Sobrevida , Taxoides/administração & dosagem , Taxoides/efeitos adversos , Resultado do Tratamento , Reino Unido , GencitabinaRESUMO
BACKGROUND: The most prevalent form of bone cancer is osteosarcoma (OS), which is associated with poor prognosis in case of metastases formation. Mice harbouring liver kinase B1 (LKB1+/-) develop osteoblastoma-like tumours. Therefore, we asked whether loss of LKB1 gene has a role in the pathogenesis of human OS. METHODS: Osteosarcomas (n=259) were screened for LKB1 and sirtuin 1 (SIRT1) protein expression using immunohistochemistry and western blot. Those cases were also screened for LKB1 genetic alterations by next-generation sequencing, Sanger sequencing, restriction fragment length polymorphism and fluorescence in situ hybridisation approaches. We studied LKB1 protein degradation through SIRT1 expression. MicroRNA expression investigations were also conducted to identify the microRNAs involved in the SIRT1/LKB1 pathway. RESULTS: Forty-one per cent (106 out of 259) OS had lost LKB1 protein expression with no evident genetic anomalies. We obtained evidence that SIRT1 impairs LKB1 protein stability, and that SIRT1 depletion leads to accumulation of LKB1 in OS cell lines resulting in growth arrest. Further investigations revealed the role of miR-204 in the regulation of SIRT1 expression, which impairs LKB1 stability. CONCLUSIONS: We demonstrated the involvement of sequential regulation of miR-204/SIRT1/LKB1 in OS cases and showed a mechanism for the loss of expression of LKB1 tumour suppressor in this malignancy.
Assuntos
Neoplasias Ósseas/genética , Osteossarcoma/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/metabolismo , Sirtuína 1/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Anoikis/genética , Antineoplásicos/farmacologia , Benzamidas/farmacologia , Neoplasias Ósseas/metabolismo , Bortezomib/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Sobrevivência Celular/genética , Humanos , MicroRNAs/genética , Naftóis/farmacologia , Osteossarcoma/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Transdução de Sinais , Sirtuína 1/antagonistas & inibidores , Sirtuína 1/genética , Serina-Treonina Quinases TOR/metabolismo , TransfecçãoRESUMO
Chordoma is a rare malignant bone tumour with a poor prognosis and limited therapeutic options. We undertook a focused compound screen (FCS) against 1097 compounds on three well-characterized chordoma cell lines; 154 compounds were selected from the single concentration screen (1 µm), based on their growth-inhibitory effect. Their half-maximal effective concentration (EC50 ) values were determined in chordoma cells and normal fibroblasts. Twenty-seven of these compounds displayed chordoma selective cell kill and 21/27 (78%) were found to be EGFR/ERBB family inhibitors. EGFR inhibitors in clinical development were then studied on an extended cell line panel of seven chordoma cell lines, four of which were sensitive to EGFR inhibition. Sapitinib (AstraZeneca) emerged as the lead compound, followed by gefitinib (AstraZeneca) and erlotinib (Roche/Genentech). The compounds were shown to induce apoptosis in the sensitive cell lines and suppressed phospho-EGFR and its downstream pathways in a dose-dependent manner. Analysis of substituent patterns suggested that EGFR-inhibitors with small aniline substituents in the 4-position of the quinazoline ring were more effective than inhibitors with large substituents in that position. Sapitinib showed significantly reduced tumour growth in two xenograft mouse models (U-CH1 xenograft and a patient-derived xenograft, SF8894). One of the resistant cell lines (U-CH2) was shown to express high levels of phospho-MET, a known bypass signalling pathway to EGFR. Neither amplifications (EGFR, ERBB2, MET) nor mutations in EGFR, ERBB2, ERBB4, PIK3CA, BRAF, NRAS, KRAS, PTEN, MET or other cancer gene hotspots were detected in the cell lines. Our findings are consistent with the reported (p-)EGFR expression in the majority of clinical samples, and provide evidence for exploring the efficacy of EGFR inhibitors in the treatment of patients with chordoma and studying possible resistance mechanisms to these compounds in vitro and in vivo. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
Assuntos
Antineoplásicos/farmacologia , Cordoma/tratamento farmacológico , Receptores ErbB/antagonistas & inibidores , Cloridrato de Erlotinib/farmacologia , Quinazolinas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cordoma/patologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Gefitinibe , Humanos , Camundongos , Transdução de Sinais , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
AIMS: We recently reported that 95% of chondroblastomas harbour a p.K36M mutation in either H3F3A (chromosome 1) or H3F3B (chromosome 17), with the majority involving H3F3B. The aim of this study was to assess the expression of the K36M-mutated protein by immunohistochemistry in a large group of tumours. METHODS AND RESULTS: One thousand eight hundred and ninety-four tumours, including 85 chondroblastomas and 10 clear-cell chondrosarcomas, were studied; of these, 82 chondroblastomas and one clear-cell chondrosarcoma known to harbour the H3F3 p.K36M mutation expressed the mutated protein. Three chondroblastomas and nine clear-cell chondrosarcomas wild type for H3F3A/H3F3B were negative for p.K36M immunoexpression. The remaining 1799 cases tested, 545 of which were known to be wild type for the H3F3A and H3F3B p.K36M mutations, included 1047 primary bone tumours, and 507 soft tissue and joint tumours. Two hundred and forty-five other tumour types not expected to harbour the mutation were negative for p.K36M immunoexpression. CONCLUSIONS: Our data demonstrate the specificity and sensitivity of this immunomarker, and will be a useful adjunct for reaching a diagnosis of chondroblastoma.
Assuntos
Biomarcadores Tumorais/genética , Neoplasias Ósseas/diagnóstico , Condroblastoma/diagnóstico , Condrossarcoma/diagnóstico , Histonas/genética , Substituição de Aminoácidos , Anticorpos , Biomarcadores Tumorais/metabolismo , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Condroblastoma/genética , Condroblastoma/metabolismo , Condrossarcoma/genética , Condrossarcoma/metabolismo , Histonas/metabolismo , Humanos , Imuno-Histoquímica , Mutação , Sensibilidade e EspecificidadeAssuntos
Dedos , Edema/diagnóstico por imagem , Edema/etiologia , Feminino , Dedos/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , DorAssuntos
Dedos , Edema/diagnóstico por imagem , Edema/etiologia , Feminino , Dedos/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , DorRESUMO
Melanotic or melanocytic schwannoma is a rare tumour usually involving spinal nerve roots but can also present at other anatomical locations. Although there are less than 200 cases reported, melanotic schwannomas can have distinctive imaging features but there is limited recent literature on its often characteristic radiological appearances. Recent publication of the largest case series thus far has suggested melanotic schwannoma to be a separate entity to other schwannomata and that its reclassification to a malignant lesion be under consideration. We present a case series over an 11-year period to highlight salient imaging features with reference to the current concerns regarding its malignant potential.
Assuntos
Imageamento por Ressonância Magnética/métodos , Melanoma/patologia , Neurilemoma/patologia , Neoplasias do Sistema Nervoso Periférico/patologia , Nervos Espinhais/patologia , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Parosteal osteosarcoma, low-grade central osteosarcoma, and fibrous dysplasia share similar histological features that may pose a diagnostic challenge. The detection of GNAS mutations in primary bone tumors has been useful in clinical practice for diagnosing fibrous dysplasia. However, the recent report of GNAS mutations being detected in a significant proportion of parosteal osteosarcoma challenges the specificity of this mutation. As the number of cases reported in this study was small we set out to determine if these results could be reproduced. We studied 97 formalin-fixed paraffin-embedded low-grade osteosarcomas from 90 patients including 62 parosteal osteosarcomas, of which MDM2 amplification was detected in 79%, 11 periosteal osteosarcomas and 24 low-grade central osteosarcoma samples. The mutational status of GNAS was analyzed in codons p.R201, p.Q227, and other less common GNAS alterations by bidirectional Sanger sequencing and/or next generation sequencing using the Life Technologies Ion Torrent platform. GNAS mutations were not detected in any of the low-grade osteosarcomas from which informative DNA was extracted. Our findings therefore support prior observations that GNAS mutations are highly specific for fibrous dysplasia and occur rarely, if ever, in parosteal and other low-grade osteosarcomas.