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The determination of an optimal treatment plan for an individual patient with rectal cancer is a complex process. In addition to decisions relating to the intent of rectal cancer surgery (ie, curative or palliative), consideration must also be given to the likely functional results of treatment, including the probability of maintaining or restoring normal bowel function/anal continence and preserving genitourinary functions. Particularly for patients with distal rectal cancer, finding a balance between curative-intent therapy while having minimal impact on quality of life can be challenging. Furthermore, the risk of pelvic recurrence is higher in patients with rectal cancer compared with those with colon cancer, and locally recurrent rectal cancer is associated with a poor prognosis. Careful patient selection and the use of sequenced multimodality therapy following a multidisciplinary approach is recommended. These NCCN Guidelines Insights detail recent updates to the NCCN Guidelines for Rectal Cancer, including the addition of endoscopic submucosal dissection as an option for early-stage rectal cancer, updates to the total neoadjuvant therapy approach based on the results of recent clinical trials, and the addition of a "watch-and-wait" nonoperative management approach for clinical complete responders to neoadjuvant therapy.
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Neoplasias Retais , Humanos , Neoplasias Retais/terapia , Neoplasias Retais/diagnóstico , Neoplasias Retais/patologia , Terapia Neoadjuvante/métodos , Terapia Neoadjuvante/normas , Terapia Combinada/métodos , Estadiamento de Neoplasias , Oncologia/normas , Oncologia/métodosRESUMO
Colorectal cancer (CRC) is the fourth most frequently diagnosed cancer and the second leading cause of cancer death in the United States. Management of disseminated metastatic CRC involves various active drugs, either in combination or as single agents. The choice of therapy is based on consideration of the goals of therapy, the type and timing of prior therapy, the mutational profile of the tumor, and the differing toxicity profiles of the constituent drugs. This manuscript summarizes the data supporting the systemic therapy options recommended for metastatic CRC in the NCCN Guidelines for Colon Cancer.
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Neoplasias do Colo , Humanos , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/terapia , Neoplasias do Colo/patologia , Neoplasias do Colo/tratamento farmacológico , Oncologia/normas , Oncologia/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Estados UnidosRESUMO
This discussion summarizes the NCCN Clinical Practice Guidelines for managing squamous cell anal carcinoma, which represents the most common histologic form of the disease. A multidisciplinary approach including physicians from gastroenterology, medical oncology, surgical oncology, radiation oncology, and radiology is necessary. Primary treatment of perianal cancer and anal canal cancer are similar and include chemoradiation in most cases. Follow-up clinical evaluations are recommended for all patients with anal carcinoma because additional curative-intent treatment is possible. Biopsy-proven evidence of locally recurrent or persistent disease after primary treatment may require surgical treatment. Systemic therapy is generally recommended for extrapelvic metastatic disease. Recent updates to the NCCN Guidelines for Anal Carcinoma include staging classification updates based on the 9th edition of the AJCC Staging System and updates to the systemic therapy recommendations based on new data that better define optimal treatment of patients with metastatic anal carcinoma.
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Neoplasias do Ânus , Carcinoma de Células Escamosas , Humanos , Biópsia , OncologiaRESUMO
Epithelia within tubular organs form and expand lumens. Failure of these processes can result in serious developmental anomalies. Although tight junction assembly is crucial to epithelial polarization, the contribution of specific tight junction proteins to lumenogenesis is undefined. Here, we show that ZO-1 (also known as TJP1) is necessary for the formation of single lumens. Epithelia lacking this tight junction scaffolding protein form cysts with multiple lumens and are defective in the earliest phases of polarization, both in two and three dimensions. Expression of ZO-1 domain-deletion mutants demonstrated that the actin-binding region and U5-GuK domain are crucial to single lumen development. For actin-binding region, but not U5-GuK domain, mutants, this could be overcome by strong polarization cues from the extracellular matrix. Analysis of the U5-GuK binding partners shroom2, α-catenin and occludin showed that only occludin deletion led to multi-lumen cysts. Like ZO-1-deficiency, occludin deletion led to mitotic spindle orientation defects. Single lumen formation required the occludin OCEL domain, which binds to ZO-1. We conclude that ZO-1-occludin interactions regulate multiple phases of epithelial polarization by providing cell-intrinsic signals that are required for single lumen formation.
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Actinas/metabolismo , Técnicas de Cultura de Células/métodos , Polaridade Celular , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Ocludina/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo , Linhagem Celular , Proliferação de Células , Técnicas de Silenciamento de Genes , Humanos , Mitose , Morfogênese , Fenótipo , Ligação Proteica , Transporte Proteico , Junções Íntimas/metabolismo , Proteína da Zônula de Oclusão-1/química , alfa Catenina/metabolismoRESUMO
The Hippo pathway effector Yes-associated protein (YAP) regulates liver size by promoting cell proliferation and inhibiting apoptosis. However, recent in vivo studies suggest that YAP has important cellular functions other than controlling proliferation and apoptosis. Transgenic YAP expression in mouse hepatocytes results in severe jaundice. A possible explanation for the jaundice could be defects in adherens junctions that prevent bile from leaking into the blood stream. Indeed, immunostaining of E-cadherin and electron microscopic examination of bile canaliculi of Yap transgenic livers revealed abnormal adherens junction structures. Using primary hepatocytes from Yap transgenic livers and Yap knockout livers, we found that YAP antagonizes E-cadherin-mediated cell-cell junction assembly by regulating the cellular actin architecture, including its mechanical properties (elasticity and cortical tension). Mechanistically, we found that YAP promoted contractile actin structure formation by upregulating nonmuscle myosin light chain expression and cellular ATP generation. Thus, by modulating actomyosin organization, YAP may influence many actomyosin-dependent cellular characteristics, including adhesion, membrane protrusion, spreading, morphology, and cortical tension and elasticity, which in turn determine cell differentiation and tissue morphogenesis.
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Citoesqueleto de Actina/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Junções Aderentes/fisiologia , Hepatócitos/fisiologia , Fosfoproteínas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Caderinas , Proteínas de Ciclo Celular , Células Cultivadas , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Fosfoproteínas/genética , Fatores de Transcrição de Domínio TEA , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Sinalização YAPRESUMO
OBJECTIVE: In the K/BxN mouse model of rheumatoid arthritis, T cells reactive for the self antigen glucose-6-phosphate isomerase (GPI) escape negative selection even though GPI expression is ubiquitous. We sought to determine whether insufficient GPI presentation could account for the failure of negative selection and for the development of arthritis. METHODS: To increase the antigen presentation of GPI, we generated transgenic mice expressing a membrane-bound form of GPI (mGPI) and crossed them with K/BxN mice. A monoclonal antibody specific for the α-chain of the KRN T cell receptor was generated to examine the fate of GPI-specific T cells. RESULTS: The mGPI-transgenic mice presented GPI more efficiently and showed a dramatic increase in negative selection and an inhibition of arthritis. Interestingly, thymic negative selection remained incomplete in these mice, and the escaped autoreactive T cells were anergic in the peripheral lymphoid organs, suggesting that enhanced antigen presentation also induces peripheral tolerance. Despite this apparent tolerance induction toward GPI, these mice developed a chronic wasting disease, characterized by colonic inflammation with epithelial dysplasia, as well as a dramatic reduction in Treg cells. CONCLUSION: These data indicate that insufficient autoantigen expression or presentation results in defects of both central and peripheral tolerance in the K/BxN mice. Our findings also support the idea that insufficient autoantigen levels may underlie the development of autoimmunity.
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Apresentação de Antígeno/imunologia , Artrite Reumatoide/imunologia , Autoantígenos/imunologia , Glucose-6-Fosfato Isomerase/imunologia , Tolerância Imunológica/imunologia , Animais , Anticorpos Monoclonais/imunologia , Células da Medula Óssea/citologia , Células da Medula Óssea/imunologia , Citocinas/genética , Citocinas/imunologia , Modelos Animais de Doenças , Glucose-6-Fosfato Isomerase/genética , Camundongos , Camundongos Transgênicos , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/imunologiaRESUMO
Detection of circulating tumor DNA (ctDNA) from plasma cell free DNA (cfDNA) has shown promise for diagnosis, therapeutic targeting, and prognosis. This study explores ctDNA detection by next generation sequencing (NGS) and associated clinicopathologic factors in patients with pancreatic adenocarcinoma (PDAC). Patients undergoing surgical exploration or resection of pancreatic lesions were enrolled with informed consent. Plasma samples (4-6 ml) were collected prior to surgery and cfDNA was recovered from 95 plasma samples. Adequate cfDNA for NGS (20 ng) was obtained from 81 patients. NGS was performed using the Oncomine Lung cfDNA assay on the Ion Torrent S5 sequencing platform. Twenty-five patients (30.9%) had detectable mutations in KRAS and/or TP53 with allele frequencies ranging from 0.05 to 8.5%, while mutations in other genes were detected less frequently and always along with KRAS or TP53. Detectable ctDNA mutations were more frequent in patients with poorly differentiated tumors, and patients without detectable ctDNA mutations showed longer survival (medians of 10.5 months vs. 18 months, p = 0.019). The detection of circulating tumor DNA in pancreatic adenocarcinomas is correlated with worse survival outcomes.
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Adenocarcinoma , DNA Tumoral Circulante , Sequenciamento de Nucleotídeos em Larga Escala , Mutação , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/mortalidade , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , DNA Tumoral Circulante/genética , DNA Tumoral Circulante/sangue , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma/sangue , Idoso de 80 Anos ou mais , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína Supressora de Tumor p53/genética , Adulto , Prognóstico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/sangue , Ácidos Nucleicos Livres/genética , Ácidos Nucleicos Livres/sangueRESUMO
BACKGROUND: Cirrhosis and its complications develop in a subgroup of patients with non-alcoholic fatty liver disease (NASH). Early detection of liver fibrosis represents an important goal of clinical care. AIM: To test the hypothesis that the development of cirrhosis in nonalcoholic fatty liver disease patients is preceded by the long-term trends of platelet counts and Fib-4 scores. METHODS: We identified all patients in our healthcare system who had undergone fibrosis staging by liver biopsy or magnetic resonance elastography (MRE) for non-alcoholic fatty liver disease during the past decade (n = 310). Platelet counts, serum glutamic-pyruvic transaminase and serum glutamic oxalacetic transaminase values preceding the staging tests were extracted from the electronic medical record system, and Fib-4 scores were calculated. Potential predictors of advanced fibrosis were evaluated using multivariate regression analysis. RESULTS: Significant decreases in platelet counts and increases in Fib-4 scores were observed in all fibrosis stages, particularly in patients with cirrhosis. In the liver biopsy group, the presence of cirrhosis was best predicted by the combination of the Fib-4 score at the time closest to staging (P < 0.0001), the presence of diabetes (P = 0.0001), and the correlation coefficient of the preceding time-dependent drop in platelet count (P = 0.044). In the MRE group, Fib4 score (P = 0.0025) and platelet drop (P = 0.0373) were significant predictors. In comparison, the time-dependent rise of the Fib-4 score did not contribute in a statistically significant way. CONCLUSION: Time-dependent changes in platelet counts and Fib-4 scores contribute to the prediction of cirrhosis in NASH patients with biopsy- or MRE-staged fibrosis. Their incorporation into predictive algorithms may assist in the earlier identification of high-risk patients.
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BACKGROUND: Electronic medical records (EMRs) are adopted for storing patient-related healthcare information. Using data mining techniques, it is possible to make use of and derive benefit from this massive amount of data effectively. We aimed to evaluate validity of data extracted by the Customized eXtraction Program (CXP). METHODS: The CXP extracts and structures data in rapid standardised processes. The CXP was programmed to extract TNFα-native active ulcerative colitis (UC) patients from EMRs using defined International Classification of Disease-10 (ICD-10) codes. Extracted data were read in parallel with manual assessment of the EMR to compare with CXP-extracted data. RESULTS: From the complete EMR set, 2,802 patients with code K51 (UC) were extracted. Then, CXP extracted 332 patients according to inclusion and exclusion criteria. Of these, 97.5% were correctly identified, resulting in a final set of 320 cases eligible for the study. When comparing CXP-extracted data against manually assessed EMRs, the recovery rate was 95.6-101.1% over the years with 96.1% weighted average sensitivity. CONCLUSION: Utilisation of the CXP software can be considered as an effective way to extract relevant EMR data without significant errors. Hence, by extracting from EMRs, CXP accurately identifies patients and has the capacity to facilitate research studies and clinical trials by finding patients with the requested code as well as funnel down itemised individuals according to specified inclusion and exclusion criteria. Beyond this, medical procedures and laboratory data can rapidly be retrieved from the EMRs to create tailored databases of extracted material for immediate use in clinical trials.
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Mineração de Dados , Registros Eletrônicos de Saúde , Mineração de Dados/métodos , Bases de Dados Factuais , Humanos , Classificação Internacional de DoençasRESUMO
Background: Liver parenchyma that resides outside of the normal hepatic confines is defined as accessory liver if in communication with the native biliary tree, or ectopic liver (EL) if it is not. EL can develop in a variety of tissues, including but not limited to the gallbladder, the hepatic ligaments, the pancreas, and retroperitoneum. EL has an increased propensity for malignant degeneration resulting in hepatocellular carcinoma (HCC). Presentation: A 67-year-old Korean male presented with epigastric discomfort and was found to have an elevation in his transaminases. Cross-sectional imaging demonstrated a 1.3 cm solid mass in the body of the pancreas with features concerning for either a pancreatic ductal adenocarcinoma or pancreatic neuroendocrine tumor. Subsequent endoscopic ultrasound and fine needle aspiration demonstrated cells of epithelial origin with hepatocellular differentiation. A robotic-assisted distal pancreatectomy and splenectomy was performed with final pathology demonstrating a well-differentiated HCC. Conclusions: EL with malignant degeneration resulting in HCC requires surgical excision. The majority of patients reported with EL resulting in HCC in the pancreas have had the tumors located in the body and tail. Therefore, definitive treatment requires distal pancreatectomy and splenectomy. Herein, we describe the presentation, workup, and definitive treatment of HCC arising in the pancreas.
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BACKGROUND: Primary systemic therapy in resectable pancreatic cancer is currently under investigation. FOLFIRINOX has been shown to be effective in both the adjuvant and metastatic settings and is increasingly being used on and off study in the neoadjuvant setting. The objective pathologic response elicited by this regimen in truly resectable disease has not as yet been widely reported. METHODS: This analysis focuses on 14 patients with resectable pancreatic cancer who were treated in a pilot study of primary systemic therapy, using 4 cycles of neoadjuvant FOLFIRINOX before surgery. A dedicated pancreatic pathologist reviewed all of the subsequent surgical specimens to assess the degree of tumor regression elicited by this approach, according to the scoring system proposed by Evans. RESULTS: Four patients (28.6%) had Evans grade I, 4 (28.6%) Evans grade IIa, 2 (14.2%) Evans grade IIb, and 4 (28.6%) Evans grade III response to the primary systemic therapy. There were no Evans grade IV responses. CONCLUSIONS: The results are intriguing with 28% of the specimens showing destruction of <10% of tumor cells, and only 28% achieving >90% destruction of tumor cells. The significant variation in response once again confirms the known heterogeneity in the biology of this cancer and clearly FOLFIRINOX is not equally effective in all patients. Future studies evaluating primary systemic therapy in pancreatic cancer should examine the optimal duration of therapy before surgery and should include a standardized pathologic grading scheme to better enable comparison of results.
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Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Neoadjuvante/métodos , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Adenocarcinoma/terapia , Adulto , Idoso , Biópsia por Agulha , Causas de Morte , Quimioterapia Adjuvante , Estudos de Coortes , Terapia Combinada , Intervalo Livre de Doença , Feminino , Fluoruracila/uso terapêutico , Hospitais Universitários , Humanos , Imuno-Histoquímica , Irinotecano/uso terapêutico , Estimativa de Kaplan-Meier , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oxaliplatina/uso terapêutico , Pancreatectomia/métodos , Neoplasias Pancreáticas/terapia , Projetos Piloto , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida , Resultado do TratamentoRESUMO
Idiosyncratic hepatotoxicity is a leading reason for the discontinuation or dose modification of Food and Drug Administration (FDA)-approved medications in the United States. We report the case of a 53-year-old woman with chronic myeloid leukemia who developed acute cholestatic hepatitis in response to the tyrosine kinase inhibitor nilotinib. Nilotinib was discontinued, and the patient's liver function tests normalized over the next 3 months. We conclude that nilotinib may cause life-threatening hepatotoxicity and recommend that patients on the medication undergo regular monitoring of their liver tests.
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Graft-versus-host disease (GVHD) is a complication of hematopoietic stem cell transplantation (HSCT) that affects multiple organs. GVHD-associated intestinal damage can be separated into two distinct phases, initiation and propagation, which correspond to conditioning-induced damage and effector T cell activation and infiltration, respectively. Substantial evidence indicates that intestinal damage induced by pretransplant conditioning is a key driver of GVHD initiation. Here, we aimed to determine the impact of dysregulated intestinal permeability on the subsequent GVHD propagation phase. The initiation phase of GVHD was unchanged in mice lacking long MLCK (MLCK210), an established regulator of epithelial tight junction permeability. However, MLCK210-deficient mice were protected from sustained barrier loss and exhibited limited GVHD propagation, as indicated by reduced histopathology, fewer CD8+ effector T cells in the gut, and improved overall survival. Consistent with these findings, intestinal epithelial MLCK210 expression and enzymatic activity were similarly increased in human and mouse GVHD biopsies. Intestinal epithelial barrier loss mediated by MLCK210 is therefore a key driver of the GVHD propagation. These data suggest that inhibition of MLCK210-dependent barrier regulation may be an effective approach to limiting GVHD progression.
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Linfócitos T CD8-Positivos/imunologia , Doença Enxerto-Hospedeiro/imunologia , Transplante de Células-Tronco Hematopoéticas , Mucosa Intestinal/imunologia , Quinase de Cadeia Leve de Miosina/imunologia , Junções Íntimas/imunologia , Aloenxertos , Animais , Linfócitos T CD8-Positivos/patologia , Feminino , Doença Enxerto-Hospedeiro/patologia , Mucosa Intestinal/patologia , Camundongos , Camundongos Endogâmicos BALB C , Junções Íntimas/patologiaRESUMO
The oligometastasis hypothesis suggests a spectrum of metastatic virulence where some metastases are limited in extent and curable with focal therapies. A subset of patients with metastatic colorectal cancer achieves prolonged survival after resection of liver metastases consistent with oligometastasis. Here we define three robust subtypes of de novo colorectal liver metastasis through integrative molecular analysis. Patients with metastases exhibiting MSI-independent immune activation experience the most favorable survival. Subtypes with adverse outcomes demonstrate VEGFA amplification in concert with (i) stromal, mesenchymal, and angiogenic signatures, or (ii) exclusive NOTCH1 and PIK3C2B mutations with E2F/MYC activation. Molecular subtypes complement clinical risk stratification to distinguish low-risk, intermediate-risk, and high-risk patients with 10-year overall survivals of 94%, 45%, and 19%, respectively. Our findings provide a framework for integrated classification and treatment of metastasis and support the biological basis of curable oligometastatic colorectal cancer. These concepts may be applicable to many patients with metastatic cancer.
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Neoplasias Colorretais/genética , Amplificação de Genes , Neoplasias Hepáticas/genética , Mutação , Adulto , Idoso , Idoso de 80 Anos ou mais , Classe II de Fosfatidilinositol 3-Quinases/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Feminino , Perfilação da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Receptor Notch1/genética , Fator A de Crescimento do Endotélio Vascular/genéticaRESUMO
In the originally published version of this Article, the affiliation details for Kevin P. White inadvertently omitted 'Tempus Labs, Chicago, IL, 60654, USA'. This has now been corrected in both the PDF and HTML versions of the Article.
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Relapse of hepatitis C virus (HCV) genotype 1 infection after combination therapy with sofosbuvir and ledipasvir is unusual. We report a treatment-naïve, non-cirrhotic patient in whom the relapse of genotype 1b HCV infection was accompanied by de novo cryoglobulinemic vasculitis and glomerulonephritis, requiring hemodialysis for acute renal failure. Sequence analysis revealed several resistance-associated variants in the HCV NS5a gene but not in NS3/4A. The patient's vasculitis was successfully treated with immunosuppression and plasmapheresis, followed by retreatment of HCV with a combination of sofosbuvir, simeprevir, and ribavirin. The patient achieved sustained virological response, recovered his renal function, and remains in remission from cryoglobulinemia.
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Aneurysmal bone cyst (ABC) is a locally aggressive osseous lesion that typically occurs during the first two decades of life. ABC was regarded historically as a nonneoplastic process, but recent cytogenetic data have shown clonal rearrangements of chromosomal bands 16q22 and 17p13, indicating a neoplastic basis in at least some ABCs. Herein we show that a recurring ABC chromosomal translocation t(16;17)(q22;p13) creates a fusion gene in which the osteoblast cadherin 11 gene (CDH11) promoter region on 16q22 is juxtaposed to the entire ubiquitin-specific protease USP6 (Tre2) coding sequence on 17p13. CDH11-USP6 fusion transcripts were demonstrated only in ABC with t(16;17) but other ABCs had CDH11 or USP6 rearrangements resulting from alternate cytogenetic mechanisms. CDH11 is expressed strongly in bone, and our findings implicate a novel oncogenic mechanism in which deregulated USP6 transcription results from juxtaposition to the highly active CDH11 promoter.
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Cistos Ósseos Aneurismáticos/genética , Caderinas/genética , Endopeptidases/genética , Proteínas de Fusão Oncogênica/genética , Proteínas Oncogênicas/genética , Translocação Genética , Adolescente , Cistos Ósseos Aneurismáticos/diagnóstico , Criança , Cromossomos Humanos Par 16 , Cromossomos Humanos Par 17 , Feminino , Rearranjo Gênico , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas , Ubiquitina TiolesteraseRESUMO
KIT expression is a key diagnostic feature of gastrointestinal stromal tumors (GISTs), and virtually all of the GISTs express oncogenic forms of the KIT or PDGFRA receptor tyrosine kinase proteins, which serve as therapeutic targets of imatinib mesylate (Gleevec; Novartis, Basel, Switzerland). However, KIT expression can be low in PDGFRA-mutant GISTs, increasing the likelihood of misdiagnosis as other types of sarcoma. We report that the signaling intermediate protein kinase C theta (PKCtheta) is a diagnostic marker in GISTs, including those that lack KIT expression and/or contain PDGFRA mutations. PKCtheta is strongly activated in most GISTs and hence may serve, along with KIT/PDGFRA, as a novel therapeutic target.