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1.
Laryngorhinootologie ; 2023 Dec 21.
Artigo em Alemão | MEDLINE | ID: mdl-38128577

RESUMO

Merkel cell carcinoma (MCC) is a rare but highly aggressive and rapidly expanding malignant skin tumor. It affects the periocular region in approximately 10% of cases. The current treatment recommendation for resectable non-metastatic MCC comprises total surgical excision; however, lymph node or distant metastases are often already present by the time of the diagnosis. Since an immune checkpoint inhibitor therapy with avelumab was first approved for MCC in 2016, there has been considerable improvement in mean survival compared to cytostatic therapy; at the same time, there has been a reduction in serious treatment-associated adverse events. Other immune checkpoint inhibitors are currently still in clinical trials, with very promising initial results. Because of the complexity of the diagnosis, treatment, and prognosis, it is essential that MCC patients receive interdisciplinary care in a specialized center including consultation with a tumor review board.

2.
Z Gastroenterol ; 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37871633

RESUMO

Liver injury associated with selective androgen receptor modulators (SARMs) is an issue that has not been reported often. We report a case of a previously healthy 24-year-old male, who was referred to our hospital for severe jaundice with intense pruritus. He had previously taken the SARM Enobosarm (also known as Ostarine) for muscle-building purposes. Blood serum levels of total bilirubin exceeded 30 mg/dL with only a slight elevation of liver enzymes. Liver biopsy revealed isolated hepatocellular cholestasis (bland cholestasis) with limited inflammation or necrosis. Supportive treatment was begun in our hospital with molecular adsorbent recirculation system (MARS) albumin dialysis, as well as cholestyramine for pruritus relief. During therapy, bilirubin levels and symptoms regressed, and after five sessions of dialysis, the patient could be released from our clinic in a markedly improved clinical and laboratory condition. However, bilirubin parameters regressed slowly after this, reaching normal levels as late as six months after first intake of the compound. Exome-based genetic testing brought about no pathogenic variants for cholestatic liver disease in our patient. Nevertheless, three common heterozygous polymorphisms associated with an increased risk for intrahepatic cholestasis could be identified. Our case demonstrates that SARMs can cause severe liver injuries not prominently mentioned in safety data sheets. Therefore, these compounds constitute a potential danger to the user's health. This holds especially true when taking SARMs without supervision by a medical professional, which should consist of a thorough monitoring of liver enzyme and bilirubin levels.

3.
Klin Monbl Augenheilkd ; 240(1): 24-32, 2023 Jan.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-36368663

RESUMO

Merkel cell carcinoma (MCC) is a rare but highly aggressive and rapidly expanding malignant skin tumor. It affects the periocular region in approximately 10% of cases. The current treatment recommendation for resectable non-metastatic MCC comprises total surgical excision; however, lymph node or distant metastases are often already present by the time of the diagnosis. Since an immune checkpoint inhibitor therapy with avelumab was first approved for MCC in 2016, there has been considerable improvement in mean survival compared to cytostatic therapy; at the same time, there has been a reduction in serious treatment-associated adverse events. Other immune checkpoint inhibitors are currently still in clinical trials, with very promising initial results. Because of the complexity of the diagnosis, treatment, and prognosis, it is essential that MCC patients receive interdisciplinary care in a specialized center including consultation with a tumor review board.


Assuntos
Carcinoma de Célula de Merkel , Neoplasias Cutâneas , Humanos , Carcinoma de Célula de Merkel/diagnóstico , Carcinoma de Célula de Merkel/terapia , Carcinoma de Célula de Merkel/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/terapia , Prognóstico
4.
Curr Drug Saf ; 18(3): 404-412, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35670337

RESUMO

BACKGROUND: Metamizole is one of the most used analgesic, antipyretic, and spasmolytic agents in many countries worldwide. While metamizole-induced agranulocytosis is an, albeit seldom, well-known adverse event, metamizole-associated drug-induced liver injury has been reported rarely in the literature and hence often remains unconsidered. Here, we present a unique case where metamizole-induced hepatotoxicity got unmasked by the simultaneous development of characteristic agranulocytosis. CASE REPORT: A 22-year-old woman without known conditions presented with a new onset of fever, jaundice, and maculopapular rash and explicitly denied intake of any new substances. Laboratory tests showed liver injury, granulopenia, and positive anti-nuclear and anti-mitochondrial (AMA-M2) antibodies. Liver biopsy revealed a histological pattern characteristic of drug-induced liver injury and bone marrow biopsy, the classical picture of metamizole-induced agranulocytosis. Indeed the in-depth interview of the patient unveiled metamizole consumption over the last two months. Therefore, we could diagnose metamizole-induced hepato- and myelotoxicity. Accordingly, steroid therapy led to normalization of liver parameters and stimulation with granulocyte colony- stimulating factor to leukocyte recovery. CONCLUSION: This case report is intended to increase the awareness of metamizole-associated druginduced liver injury which should always be kept in mind due to its occasionally life-threatening course. Diagnosis can be difficult particularly if anamnesis and written records are without hints for prior metamizole intake.


Assuntos
Agranulocitose , Doença Hepática Crônica Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas , Feminino , Humanos , Adulto Jovem , Adulto , Dipirona/efeitos adversos , Anti-Inflamatórios não Esteroides/efeitos adversos , Agranulocitose/induzido quimicamente , Agranulocitose/diagnóstico , Agranulocitose/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Doença Hepática Induzida por Substâncias e Drogas/etiologia
5.
Cell Oncol (Dordr) ; 45(3): 399-413, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35556229

RESUMO

PURPOSE: Synovial sarcoma (SySa) is a rare soft tissue tumor characterized by a reciprocal t(X;18) translocation. The chimeric SS18-SSX fusion protein represents the major driver of the disease, acting as aberrant transcriptional dysregulator. Oncogenic mechanisms whereby SS18-SSX mediates sarcomagenesis are incompletely understood, and strategies to selectively target SySa cells remain elusive. Based on results of Phospho-Kinase screening arrays, we here investigate the functional and therapeutic relevance of the transcription factor CREB in SySa tumorigenesis. METHODS: Immunohistochemistry of phosphorylated CREB and its downstream targets (Rb, Cyclin D1, PCNA, Bcl-xL and Bcl-2) was performed in a large cohort of SySa. Functional aspects of CREB activity, including SS18-SSX driven circuits involved in CREB activation, were analyzed in vitro employing five SySa cell lines and a mesenchymal stem cell model. CREB mediated transcriptional activity was modulated by RNAi-mediated knockdown and small molecule inhibitors (666-15, KG-501, NASTRp and Ro 31-8220). Anti-proliferative effects of the CREB inhibitor 666-15 were tested in SySa avian chorioallantoic membrane and murine xenograft models in vivo. RESULTS: We show that CREB is phosphorylated and activated in SySa, accompanied by downstream target expression. Human mesenchymal stem cells engineered to express SS18-SSX promote CREB expression and phosphorylation. Conversely, RNAi-mediated knockdown of SS18-SSX impairs CREB phosphorylation in SySa cells. Inhibition of CREB activity reduces downstream target expression, accompanied by suppression of SySa cell proliferation and induction of apoptosis in vitro and in vivo. CONCLUSION: In conclusion, our data underline an essential role of CREB in SySa tumorigenesis and provides evidence for molecular targeted therapies.


Assuntos
Sarcoma Sinovial , Animais , Apoptose , Carcinogênese , Linhagem Celular Tumoral , Humanos , Camundongos , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Sarcoma Sinovial/tratamento farmacológico , Sarcoma Sinovial/genética , Sarcoma Sinovial/metabolismo
6.
Oncogenesis ; 11(1): 20, 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35459264

RESUMO

Myxoid liposarcoma (MLS) represents a common subtype of liposarcoma molecularly characterized by a recurrent chromosomal translocation that generates a chimeric FUS-DDIT3 fusion gene. The FUS-DDIT3 oncoprotein has been shown to be crucial in MLS pathogenesis. Acting as a transcriptional dysregulator, FUS-DDIT3 stimulates proliferation and interferes with adipogenic differentiation. As the fusion protein represents a therapeutically challenging target, a profound understanding of MLS biology is elementary to uncover FUS-DDIT3-dependent molecular vulnerabilities. Recently, a specific reliance on the Hippo pathway effector and transcriptional co-regulator YAP1 was detected in MLS; however, details on the molecular mechanism of FUS-DDIT3-dependent YAP1 activation, and YAP1´s precise mode of action remain unclear. In elaborate in vitro studies, employing RNA interference-based approaches, small-molecule inhibitors, and stimulation experiments with IGF-II, we show that FUS-DDIT3-driven IGF-IR/PI3K/AKT signaling promotes stability and nuclear accumulation of YAP1 via deregulation of the Hippo pathway. Co-immunoprecipitation and proximity ligation assays revealed nuclear co-localization of FUS-DDIT3 and YAP1/TEAD in FUS-DDIT3-expressing mesenchymal stem cells and MLS cell lines. Transcriptome sequencing of MLS cells demonstrated that FUS-DDIT3 and YAP1 co-regulate oncogenic gene signatures related to proliferation, cell cycle progression, apoptosis, and adipogenesis. In adipogenic differentiation assays, we show that YAP1 critically contributes to FUS-DDIT3-mediated adipogenic differentiation arrest. Taken together, our study provides mechanistic insights into a complex FUS-DDIT3-driven network involving IGF-IR/PI3K/AKT signals acting on Hippo/YAP1, and uncovers substantial cooperative effects of YAP1 and FUS-DDIT3 in the pathogenesis of MLS.

7.
Am J Hum Genet ; 109(5): 928-943, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35397207

RESUMO

Organ fibrosis is a shared endpoint of many diseases, yet underlying mechanisms are not well understood. Several pathways governed by the primary cilium, a sensory antenna present on most vertebrate cells, have been linked with fibrosis. Ciliopathies usually start early in life and represent a considerable disease burden. We performed massively parallel sequencing by using cohorts of genetically unsolved individuals with unexplained liver and kidney failure and correlated this with clinical, imaging, and histopathological analyses. Mechanistic studies were conducted with a vertebrate model and primary cells. We detected bi-allelic deleterious variants in TULP3, encoding a critical adaptor protein for ciliary trafficking, in a total of 15 mostly adult individuals, originating from eight unrelated families, with progressive degenerative liver fibrosis, fibrocystic kidney disease, and hypertrophic cardiomyopathy with atypical fibrotic patterns on histopathology. We recapitulated the human phenotype in adult zebrafish and confirmed disruption of critical ciliary cargo composition in several primary cell lines derived from affected individuals. Further, we show interaction between TULP3 and the nuclear deacetylase SIRT1, with roles in DNA damage repair and fibrosis, and report increased DNA damage ex vivo. Transcriptomic studies demonstrated upregulation of profibrotic pathways with gene clusters for hypertrophic cardiomyopathy and WNT and TGF-ß signaling. These findings identify variants in TULP3 as a monogenic cause for progressive degenerative disease of major organs in which affected individuals benefit from early detection and improved clinical management. Elucidation of mechanisms crucial for DNA damage repair and tissue maintenance will guide novel therapeutic avenues for this and similar genetic and non-genomic diseases.


Assuntos
Cardiomiopatia Hipertrófica , Cílios , Adulto , Animais , Cardiomiopatia Hipertrófica/metabolismo , Criança , Cílios/genética , Cílios/metabolismo , Fibrose , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Rim , Fígado , Mutação/genética , Peixe-Zebra/genética
8.
Mod Pathol ; 35(4): 489-494, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34725446

RESUMO

Osteoma is a benign bone forming tumor predominantly arising on the surface of craniofacial bones. While the vast majority of osteomas develops sporadically, a small subset of cases is associated with Gardner syndrome, a phenotypic variant of familial adenomatous polyposis caused by mutations in the APC gene resulting in aberrant activation of WNT/ß-catenin signaling. In a sequencing analysis on a cohort of sporadic, non-syndromal osteomas, we identified hotspot mutations in the CTNNB1 gene (encoding ß-catenin) in 22 of 36 cases (61.1%), harbouring allelic frequencies ranging from 0.04 to 0.53, with the known S45P variant representing the most frequent alteration. Based on NanoString multiplex expression profiling performed in a subset of cases, CTNNB1-mutated osteomas segregated in a defined "WNT-cluster", substantiating functionality of CTNNB1 mutations which are associated with ß-catenin stabilization. Our findings for the first time convincingly show that osteomas represent genetically-driven neoplasms and provide evidence that aberrant WNT/ß-catenin signaling plays a fundamental role in their pathogenesis, in line with the well-known function of WNT/ß-catenin in osteogenesis. Our study contributes to a better understanding of the molecular pathogenesis underlying osteoma development and establishes a helpful diagnostic molecular marker for morphologically challenging cases.


Assuntos
Osteoma , beta Catenina , Proteína da Polipose Adenomatosa do Colo/genética , Genes APC , Humanos , Mutação , Osteoma/genética , beta Catenina/genética , beta Catenina/metabolismo
9.
Liver Int ; 41(10): 2427-2432, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34358398

RESUMO

Cryptogenic elevation of transaminases in childhood can in a few instances be linked to rare hereditary causes. In this paper, a 7-year old girl is reported who was diagnosed with elevated transaminases of unknown origin since infancy. A liver biopsy showed bridging fibrosis, pale eosinophilic intracytoplasmic hepatocellular inclusions and enlarged endoplasmic reticulum cisternae in the hepatocytes. Whole-exome sequencing revealed a homozygous in-frame deletion of 3 base pairs in the haptoglobin gene. The patient is anhaptoglobinemic measured by standard laboratory turbidometry, which was confirmed by Western Blotting and thereby shown to affect both protein chains of haptoglobin. A polyclonal antibody revealed haptoglobin retention in hepatocytes suggesting a defect in haptoglobin secretion. A novel, previously unknown haptoglobin storage disease is suspected to be the reason for the elevated liver enzymes and tissue abnormalities in this patient. The pathophysiology appears to be similar to endoplasmic reticulum storage diseases like alpha-1-antitrypsin-deficiency.


Assuntos
Haptoglobinas , Deficiência de alfa 1-Antitripsina , Criança , Feminino , Haptoglobinas/genética , Hepatócitos/patologia , Homozigoto , Humanos , Fígado/patologia , Cirrose Hepática/patologia , Deficiência de alfa 1-Antitripsina/patologia
10.
Oncotarget ; 11(45): 4123-4137, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33227073

RESUMO

INTRODUCTION: The underlying molecular mechanisms of parotid gland carcinomas (PGC) are still unknown. Knowledge about the tumor-driving signaling pathways is necessary either for diagnostics or developing new therapeutic options in this heterogeneous and rare entity. MATERIAL AND METHODS: 94 matching RNA formalin-fixed and paraffin-embedded tissue samples from PGC and the corresponding non-tumor area, RNA quality and quantity were sufficient for gene expression profiling of 770 genes using the NanoString's nCounter technology. Oncogenic and tumor suppressor genes were examined in the three common PGC tumor entities: adenoid cystic carcinoma (ACC), adenocarcinoma NOS (AC-NOS), and mucoepidermoid carcinoma (MEC). RESULTS: Expression profiling and subsequent hierarchical cluster analysis clearly differentiated between non-tumor gland tissue samples and PGC. In addition expression pattern of all three entities differed. The extensive pathway analysis proved a prominent dysregulation of the Wnt signaling pathway in the three PGC entities. Moreover, transcript upstream analysis demonstrated a pronounced activation of the PI3K pathway in ACC and MEC. DISCUSSION: Our findings revealed divergent molecular expression profiles in MEC, ACC and AC-NOS that are presently studied for their potential application in PGC diagnostics. Importantly, identification of Wnt and PI3K signaling in PGC revealed novel options of PGC therapy.

11.
PLoS One ; 15(3): e0230025, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32155648

RESUMO

Intestinal cells control delivery of lipids to the body by adsorption, storage and secretion. Copper (Cu) is an important trace element and has been shown to modulate lipid metabolism. Mutation of the liver Cu exporter ATP7B is the cause of Wilson disease and is associated with Cu accumulation in different tissues. To determine the relationship of Cu and lipid homeostasis in intestinal cells, a CRISPR/Cas9 knockout of ATP7B (KO) was introduced in Caco-2 cells. KO cells showed increased sensitivity to Cu, elevated intracellular Cu storage, and induction of genes regulating oxidative stress. Chylomicron structural protein ApoB48 was significantly downregulated in KO cells by Cu. Apolipoproteins ApoA1, ApoC3 and ApoE were constitutively induced by loss of ATP7B. Formation of small sized lipid droplets (LDs) was enhanced by Cu, whereas large sized LDs were reduced. Cu reduced triglyceride (TG) storage and secretion. Exposure of KO cells to oleic acid (OA) resulted in enhanced TG storage. The findings suggest that Cu represses intestinal TG lipogenesis, while loss of ATP7B results in OA-induced TG storage.


Assuntos
ATPases Transportadoras de Cobre/deficiência , ATPases Transportadoras de Cobre/genética , Cobre/metabolismo , Metabolismo dos Lipídeos/genética , Células CACO-2 , Regulação da Expressão Gênica/genética , Técnicas de Inativação de Genes , Homeostase/genética , Humanos , Mucosa Intestinal/metabolismo
12.
Sci Rep ; 10(1): 3368, 2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32099073

RESUMO

Desmoid-type fibromatosis (DTF, aggressive fibromatosis) is a non-metastasizing mesenchymal neoplasm of deep soft tissue with a tendency towards local recurrence. Genetic alterations affecting canonical Wnt/ß-catenin signaling are reported in the majority of DTF. While most sporadic DTF harbor somatic mutations in CTNNB1, germline mutations in adenomatous polyposis coli (APC) are known to occur in hereditary DTF types (FAP, Gardner-Syndrome). Additional single nucleotide variants (SNVs) in AKT1 (E17K) and BRAF (V600E) were reported in pediatric DTF with potential clinical implications. We performed targeted next-generation sequencing (NGS) in a large cohort of 204 formalin-fixed DTF samples, comprising 22 pediatric cases (patients age ≤18 years). The mutational status was correlated with clinicopathological characteristics. Overall, deleterious CTNNB1 mutations were detected in 89% of DTF, most frequently affecting the serine/threonine phosphorylation sites T41 and S45 of ß-catenin. While the T41A CTNNB1 mutation was significantly more often identified in the mesenterial localization, DTF originating from extra-intestinal sites more frequently harbored the S45P CTNNB1 alteration. Beyond common mutations in CTNNB1, additional SNVs were demonstrated in 7% of the DTF cohort and in 18% of the pediatric DTF subgroup. The mutational spectrum included deleterious mutations in AKT1 (G311S/D and T312I), ALK (R806H and G924S), AR (A159T), EGFR (P848L), ERBB2 (H174Y), IDH2 (H354Y), KIT (V559D), RET (T1038A), SDHA (R325M), and SDHD (R115W), as characterized by in silico prediction tools. In conclusion, our study indicates that DTF may harbor a broader mutational spectrum beyond CTNNB1 mutations, comprising targetable alterations including the herewith first reported imatinib-sensitive KIT V559D mutation in DTF.


Assuntos
Fibromatose Agressiva/genética , Síndrome de Gardner/genética , Recidiva Local de Neoplasia/genética , beta Catenina/genética , Proteína da Polipose Adenomatosa do Colo/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Fibromatose Agressiva/epidemiologia , Fibromatose Agressiva/patologia , Síndrome de Gardner/epidemiologia , Síndrome de Gardner/patologia , Mutação em Linhagem Germinativa/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-akt/genética , Via de Sinalização Wnt/genética , Adulto Jovem
13.
Strahlenther Onkol ; 196(2): 117-125, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31732783

RESUMO

OBJECTIVE: To evaluate clinical, histopathologic, and radiation (RT) dose parameters in patients with extranodal low-grade (ENLG) non-Hodgkin lymphoma (NHL) and their possible impact on local control (LC) and survival. MATERIALS AND METHODS: The medical records of 159 patients with 181 histologically confirmed ENLG-NHL lesions treated at our institution were reviewed retrospectively. RESULTS: The predominant histological subtype (73%) was marginal zone lymphoma (MZL). Common lesion sites were the gastrointestinal tract (GIT; 33%), skin (26%), and orbit (21%). The majority of patients (88%) presented with stage I/II disease. Thirty-three (20%) lesions were treated with reduced-dose RT (≤30.6 Gy) and 148 lesions (80%) with conventional-dose RT (>30.6 Gy), with an overall median dose of 39.6 Gy (range 4-63). The median follow-up period was 72 months. The 10-year local control (LC), Progression-free survival (PFS), and overall survival (OS) rates were 96, 65, and 82%, respectively. Higher overall response rate (ORR; 98% vs. 94%, p = 0.001) and complete response rate (CRR; 95% vs. 73%, p = 0.001) were observed in patients treated with conventional-dose regimens than in those treated with reduced-dose regimens. Ten-year PFS (p = 0.90) and OS (p = 0.40) was similar between the two dose groups. RT was well tolerated in both dose groups, with no grade 4/5 toxicities. In the multivariate analysis, RT dose and timing (upfront or salvage) were related to LC, whereas age, histology, and complete response (CR) to RT were associated with PFS. Patient age and radiation field size impacted OS. CONCLUSION: RT is an effective and curative local treatment for early-stage FL and MZL at conventional and reduced radiation doses. Conventional-doses seems to be associated with local response improvement, without significant differences in PFS rates. Age, histology, and response to RT may influence the PFS.


Assuntos
Extensão Extranodal/radioterapia , Linfoma de Zona Marginal Tipo Células B/radioterapia , Linfoma Folicular/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Extensão Extranodal/patologia , Feminino , Seguimentos , Humanos , Linfoma de Zona Marginal Tipo Células B/patologia , Linfoma Folicular/patologia , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Dosagem Radioterapêutica , Resultado do Tratamento , Adulto Jovem
14.
Sci Rep ; 9(1): 19704, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31873172

RESUMO

Tumors of soft tissue and bone represent a heterogeneous group of neoplasias characterized by a wide variety of genetic aberrations. Albeit knowledge on tumorigenesis in mesenchymal tumors is continuously increasing, specific insights on altered signaling pathways as a basis for molecularly targeted therapeutic strategies are still sparse. The aim of this study was to determine the involvement of YAP1/TAZ-mediated signals in tumors of soft tissue and bone. Expression levels of YAP1 and TAZ were analyzed by immunohistochemistry in a large cohort of 486 tumor specimens, comprising angiosarcomas (AS), Ewing sarcomas, leiomyosarcomas, malignant peripheral nerve sheath tumors (MPNST), solitary fibrous tumors, synovial sarcomas (SySa), well-differentiated/dedifferentiated/pleomorphic and myxoid liposarcomas (MLS). Moderate to strong nuclear staining of YAP1 and TAZ was detected in 53% and 33%, respectively. YAP1 nuclear expression was most prevalent in MPNST, SySa and MLS, whereas nuclear TAZ was predominately detected in AS, MLS and MPNST. In a set of sarcoma cell lines, immunoblotting confirmed nuclear localization of YAP1 and TAZ, corresponding to their transcriptionally active pool. Suppression of YAP1/TAZ-TEAD mediated transcriptional activity significantly impaired sarcoma cell viability in vitro and in vivo. Our findings identify nuclear YAP1 and TAZ positivity as a common feature in subsets of sarcomas of soft tissue and bone and provide evidence of YAP1/TAZ-TEAD signaling as a specific liability to be considered as a new target for therapeutic intervention. Nuclear YAP1/TAZ expression may represent a biomarker suited to identify patients that could benefit from YAP1/TAZ-TEAD directed therapeutic approaches within future clinical trials.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias Ósseas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Neoplasias de Tecidos Moles/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Animais , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Embrião de Galinha , Via de Sinalização Hippo , Humanos , Sarcoma/metabolismo , Sarcoma/patologia , Neoplasias de Tecidos Moles/patologia , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas de Sinalização YAP
15.
Clin Cancer Res ; 25(12): 3718-3731, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-30814111

RESUMO

PURPOSE: Synovial sarcoma is a soft tissue malignancy characterized by a reciprocal t(X;18) translocation. The chimeric SS18-SSX fusion protein acts as a transcriptional dysregulator representing the major driver of the disease; however, the signaling pathways activated by SS18-SSX remain to be elucidated to define innovative therapeutic strategies. EXPERIMENTAL DESIGN: Immunohistochemical evaluation of the Hippo signaling pathway effectors YAP/TAZ was performed in a large cohort of synovial sarcoma tissue specimens. SS18-SSX dependency and biological function of the YAP/TAZ Hippo signaling cascade were analyzed in five synovial sarcoma cell lines and a mesenchymal stem cell model in vitro. YAP/TAZ-TEAD-mediated transcriptional activity was modulated by RNAi-mediated knockdown and the small-molecule inhibitor verteporfin. The effects of verteporfin were finally tested in vivo in synovial sarcoma cell line-based avian chorioallantoic membrane and murine xenograft models as well as a patient-derived xenograft. RESULTS: A significant subset of synovial sarcoma showed nuclear positivity for YAP/TAZ and their transcriptional targets FOXM1 and PLK1. In synovial sarcoma cells, RNAi-mediated knockdown of SS18-SSX led to significant reduction of YAP/TAZ-TEAD transcriptional activity. Conversely, SS18-SSX overexpression in SCP-1 cells induced aberrant YAP/TAZ-dependent signals, mechanistically mediated by an IGF-II/IGF-IR signaling loop leading to dysregulation of the Hippo effectors LATS1 and MOB1. Modulation of YAP/TAZ-TEAD-mediated transcriptional activity by RNAi or verteporfin treatment resulted in significant growth inhibitory effects in vitro and in vivo. CONCLUSIONS: Our preclinical study identifies an elementary role of SS18-SSX-driven YAP/TAZ signals, highlights the complex network of oncogenic signaling pathways in synovial sarcoma pathogenesis, and provides evidence for innovative therapeutic approaches.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Sarcoma Sinovial/metabolismo , Fatores de Transcrição/metabolismo , Verteporfina/farmacologia , Aciltransferases , Adolescente , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Fármacos Fotossensibilizantes/farmacologia , Sarcoma Sinovial/tratamento farmacológico , Sarcoma Sinovial/genética , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto Jovem
16.
Mol Cancer Ther ; 18(4): 834-844, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30787173

RESUMO

Myxoid liposarcoma (MLS) is an aggressive soft-tissue tumor characterized by a specific reciprocal t(12;16) translocation resulting in expression of the chimeric FUS-DDIT3 fusion protein, an oncogenic transcription factor. Similar to other translocation-associated sarcomas, MLS is characterized by a low frequency of somatic mutations, albeit a subset of MLS has previously been shown to be associated with activating PIK3CA mutations. This study was performed to assess the prevalence of PI3K/Akt signaling alterations in MLS and the potential of PI3K-directed therapeutic concepts. In a large cohort of MLS, key components of the PI3K/Akt signaling cascade were evaluated by next generation seqeuncing (NGS), fluorescence in situ hybridization (FISH), and immunohistochemistry (IHC). In three MLS cell lines, PI3K activity was inhibited by RNAi and the small-molecule PI3K inhibitor BKM120 (buparlisib) in vitro An MLS cell line-based avian chorioallantoic membrane model was applied for in vivo confirmation. In total, 26.8% of MLS cases displayed activating alterations in PI3K/Akt signaling components, with PIK3CA gain-of-function mutations representing the most prevalent finding (14.2%). IHC suggested PI3K/Akt activation in a far larger subgroup of MLS, implying alternative mechanisms of pathway activation. PI3K-directed therapeutic interference showed that MLS cell proliferation and viability significantly depended on PI3K-mediated signals in vitro and in vivo Our preclinical study underlines the elementary role of PI3K/Akt signals in MLS tumorigenesis and provides a molecularly based rationale for a PI3K-targeted therapeutic approach which may be particularly effective in the subgroup of tumors carrying activating genetic alterations in PI3K/Akt signaling components.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Lipossarcoma Mixoide/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Adulto , Idoso , Aminopiridinas/farmacologia , Animais , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Embrião de Galinha , Membrana Corioalantoide/efeitos dos fármacos , Cromonas/farmacologia , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Estudos de Coortes , Feminino , Xenoenxertos , Humanos , Lipossarcoma Mixoide/patologia , Masculino , Pessoa de Meia-Idade , Morfolinas/farmacologia , Proteínas de Fusão Oncogênica/genética , Proteínas Proto-Oncogênicas c-akt/genética , Interferência de RNA , Adulto Jovem
17.
Can J Gastroenterol Hepatol ; 2018: 2182784, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30155451

RESUMO

Background: Portal hypertension is a serious complication of liver cirrhosis. Objective: To identify relevant endoscopic findings in patients with advanced cirrhosis and consecutive portal hypertension. Methods: This was a retrospective study of liver transplant candidates who underwent upper gastrointestinal endoscopy between April 2011 and November 2015. Results: A total of 1,045 upper endoscopies were analyzed. Portal hypertensive gastric and duodenal polyps were frequently observed and were associated with thrombocytopenia (p = 0.040; OR: 2.4, 95% CI 1.04-5.50), Child-Pugh score > 6 (p = 0.033; OR: 2.3, 95% CI 1.07-4.92), Model for End Stage Liver Disease score > 16 (p = 0.030; OR: 4.1, 95% CI 1.14-15.00), and previous rubber band ligation (p < 0.001; OR = 5.2, 95% CI 2.5-10.7). These polyps often recurred after polypectomy; however, no malignant transformation occurred during the observational time until October 2017. The most common endoscopic finding was esophageal varices, observed in more than 90% of patients. Conclusion: Portal hypertensive polyposis is common in patients with advanced cirrhosis. Our data suggest that these polyps have benign characteristics.


Assuntos
Duodenopatias/complicações , Hipertensão Portal/complicações , Pólipos Intestinais/complicações , Cirrose Hepática/complicações , Gastropatias/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Duodenopatias/diagnóstico por imagem , Duodenopatias/patologia , Duodenopatias/cirurgia , Endoscopia Gastrointestinal , Varizes Esofágicas e Gástricas/diagnóstico por imagem , Varizes Esofágicas e Gástricas/etiologia , Feminino , Humanos , Pólipos Intestinais/diagnóstico por imagem , Pólipos Intestinais/patologia , Pólipos Intestinais/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Gastropatias/diagnóstico por imagem , Gastropatias/patologia , Gastropatias/cirurgia , Trombocitopenia/complicações , Adulto Jovem
18.
Cell Oncol (Dordr) ; 41(4): 455-462, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29873033

RESUMO

PURPOSE: Salivary gland cancer (SGC) is a rare and heterogeneous disease with significant differences in recurrence and metastasis characteristics. As yet, little is known about the mechanisms underlying the initiation and/or progression of these diverse tumors. In recent years, the AAA+ ATPase family members Pontin (RuvBL1, Tip49a) and Reptin (RuvBL2, Tip49b) have been implicated in various processes, including transcription regulation, chromatin remodeling and DNA damage repair, that are frequently deregulated in cancer. The aim of this study was to assess the clinical and functional significance of Reptin and Pontin expression in SGC. METHODS: Immunohistochemical staining of Pontin, Reptin, ß-catenin, Cyclin D1, TP53 and MIB-1 was performed on a collection of 94 SGC tumor samples comprising 13 different histological subtypes using tissue microarrays. RESULTS: We found that Reptin and Pontin were expressed in the majority of SGC samples across all histological subtypes. Patients with a high Reptin expression showed a significantly inferior 5-year overall survival rate compared to patients with a low Reptin expression (47.7% versus 78.3%; p = 0.033), whereas no such difference was observed for Pontin. A high Reptin expression strongly correlated with a high expression of the proliferation marker MIB-1 (p = 0.003), the cell cycle regulator Cyclin D1 (p = 0.006), accumulation of TP53 as a surrogate p53 mutation marker (p = 0.042) and cytoplasmic ß-catenin expression (p = 0.002). Increased Pontin expression was found to significantly correlate with both cytoplasmic and nuclear ß-catenin expression (p = 0.037 and p = 0.018, respectively), which is indicative for its oncogenic function. CONCLUSIONS: Our results suggest a role of Reptin and Pontin in SGC tumor progression and/or patient survival. Therefore, SGC patients exhibiting a high Reptin expression may benefit from more aggressive therapeutic regimens. Future studies should clarify whether such patients may be considered for more radical surgery, extended adjuvant therapy and/or targeted therapy.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/metabolismo , Biomarcadores Tumorais/metabolismo , Proteínas de Transporte/metabolismo , DNA Helicases/metabolismo , Neoplasias das Glândulas Salivares/diagnóstico , Neoplasias das Glândulas Salivares/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida
19.
Cell Oncol (Dordr) ; 41(5): 517-525, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29949051

RESUMO

PURPOSE: Collagen Type VI (COLVI) is an extracellular matrix protein that is upregulated in various solid tumours during tumour progression and has been shown to stimulate proliferation, suppress apoptosis and promote invasion and metastasis. It has also been described as a mediator of chemotherapy resistance and as a therapeutic target in preclinical cancer models. Here, we aimed to analyse the prognostic role of COLVI in salivary gland cancer (SGC). METHODS: Stromal COLVI protein expression was assessed in primary SGC specimens of 91 patients using immunohistochemistry (IHC). The IHC expression patterns obtained were subsequently correlated with various survival and clinicopathological features, including Ki-67 and p53 expression. RESULTS: We found that COLVI was expressed in all SGC specimens. High expression was found to be associated with features of malignancy such as high histologic grades, advanced and invasive T stages and metastatic lymph node involvement (p < 0.05 for all variables). COLVI expression was also found to correlate with both Ki-67 and p53 expression (p < 0.01). We found that high COLVI expression predicted a significantly inferior 5-year overall survival (38.3%, 55.1% and 93.8%; p = 0.002) and remained a significant predictor of prognosis in a multivariate Cox regression analysis (hazard ratio, 2.62; 95% confidence interval, 1.22-5.61; p = 0.013). In all low-risk subgroups COLVI expression identified patients with an adverse outcome. Patients receiving adjuvant radiotherapy had a poor survival when expressing high levels of COLVI. CONCLUSIONS: Our data indicate that stromal COLVI expression associates with key features of malignancy, represents a novel independent prognostic factor and may affect response to radiotherapy in SGC. Although our results warrant validation in an independent cohort, assessing stromal COLVI expression may be suitable for future diagnostic and therapeutic decision making in patients with SGC.


Assuntos
Colágeno Tipo VI/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Neoplasias das Glândulas Salivares/metabolismo , Neoplasias das Glândulas Salivares/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/genética , Proliferação de Células/genética , Proliferação de Células/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neoplasias Parotídeas/metabolismo , Neoplasias Parotídeas/patologia , Prognóstico , Análise Serial de Tecidos , Adulto Jovem
20.
Oncotarget ; 9(11): 9867-9874, 2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29515776

RESUMO

AIM: PSMA (prostate-specific membrane antigen) is physiologically expressed in normal prostate tissue and over expressed in prostate cancer cells, therefore constituting a potential target for antibody-based radioligand therapy. Very recent imaging findings reported PSMA-PET/CT uptake in various thyroid lesions. We were therefore encouraged to systematically analyse PSMA expression in different benign and malignant thyroid lesions. METHODS: Immunohistochemistry was used to detect PSMA expression in 101 thyroid lesions, while neovasculature was identified by CD34 immunostaining. RESULTS: PSMA expression in the neovasculature was significantly more frequent in malignant tumors (36/63; 57.1%) compared to benign diseases (5/38; 13.2%; p = 0.0001). In addition, PSMA expression levels in the neovasculature of poorly and undifferentiated thyroid cancers were significantly higher compared to differentiated thyroid tumors (p = 0.021). However, one case with a strong expression in follicular adenoma was identified. CONCLUSIONS: We conclude that neovascular PSMA expression is common in thyroid cancer but may also rarely be found in benign thyroid diseases, such as follicular adenoma. High expression in the tumor-associated neovasculature is predominantly found in poorly differentiated and undifferentiated (anaplastic) thyroid cancer. This knowledge is highly relevant when interpreting PSMA/PET-CT scans from patients with prostate cancer. In addition, our findings might provide a rationale for further evaluation of PSMA-targeted anti-neovascular or radioligand therapy in metastatic dedifferentiated thyroid cancer.

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