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1.
J Neurooncol ; 135(3): 487-496, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28852935

RESUMO

SHP2 is a cytoplasmic protein tyrosine phosphatase (PTPase) involved in multiple signaling pathways and was the first identified proto-oncogene PTPase. Previous work in glioblastoma (GBM) has demonstrated the role of SHP2 PTPase activity in modulating the oncogenic phenotype of adherent GBM cell lines. Mutations in PTPN11, the gene encoding SHP2, have been identified with increasing frequency in GBM. Given the importance of SHP2 in developing neural stem cells, and the importance of glioma stem cells (GSCs) in GBM oncogenesis, we explored the functional role of SHP2 in GSCs. Using paired differentiated and stem cell primary cultures, we investigated the association of SHP2 expression with the tumor stem cell compartment. Proliferation and soft agar assays were used to demonstrate the functional contribution of SHP2 to cell growth and transformation. SHP2 expression correlated with SOX2 expression in GSC lines and was decreased in differentiated cells. Forced differentiation of GSCs by removal of growth factors, as confirmed by loss of SOX2 expression, also resulted in decreased SHP2 expression. Lentiviral-mediated knockdown of SHP2 inhibited proliferation. Finally, growth in soft-agar was similarly inhibited by loss of SHP2 expression. Our results show that SHP2 function is required for cell growth and transformation of the GSC compartment in GBM.


Assuntos
Neoplasias Encefálicas/enzimologia , Carcinogênese/metabolismo , Proliferação de Células/fisiologia , Glioma/enzimologia , Células-Tronco Neoplásicas/enzimologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Adulto , Idoso , Neoplasias Encefálicas/patologia , Carcinogênese/patologia , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Glioma/patologia , Humanos , Masculino , Células-Tronco Neoplásicas/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proto-Oncogene Mas , Fatores de Transcrição SOXB1/metabolismo , Alicerces Teciduais
2.
Development ; 139(11): 1903-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22513377

RESUMO

Cerebellum development depends on the correct differentiation of progenitors into neurons, a process controlled by a transcriptional program that remains poorly understood. Here we show that neural-specific deletion of the BTB/POZ zinc-finger transcription factor-encoding gene Rp58 (Znf238, Zfp238) causes severe cerebellar hypoplasia and developmental failure of Purkinje neurons, Bergmann glia and granule neurons. Deletion of Rp58 in mouse embryonic Atoh1(+) progenitors leads to strong defects in growth and foliation owing to its crucial role in the differentiation of granule neurons. Analysis of the Rp58 mutant at E14.5 demonstrates that Rp58 is required for the development of both glutamatergic and GABAergic neurons. Rp58 mutants show decreased proliferation of glutamatergic progenitors at E14.5. In addition, Rp58 ablation results in a reduced number of GABAergic Pax2(+) neurons at E16.5 together with defects in the transcriptional program of ventricular zone progenitors. Our results indicate that Rp58 is essential for the growth and organization of the cerebellum and regulates the development of both GABAergic and glutamatergic neurons.


Assuntos
Padronização Corporal/fisiologia , Cerebelo/embriologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Neurogênese/fisiologia , Proteínas Repressoras/fisiologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Cerebelo/crescimento & desenvolvimento , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento/genética , Imuno-Histoquímica , Hibridização In Situ , Camundongos , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Repressoras/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo
3.
Leuk Lymphoma ; 64(9): 1554-1561, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37317991

RESUMO

Increased rates of clinically significant bleeding have been reported with ibrutinib, however, limited data is available on the risk when given with concomitant therapeutic anticoagulation. We analyzed the incidence of major bleeding in 64 patient exposures that received ibrutinib with concomitant therapeutic anticoagulation. Major bleeding was observed in 5/64 (8%) patient exposures. The highest incidence was observed with rivaroxaban (3/17, 18%), followed by apixaban (2/35, 6%). No major bleeding events were seen with enoxaparin (n = 10). A total of 38% of patient exposures received a concomitant antiplatelet agent along with therapeutic anticoagulation. Among these patients, one (4%) experienced a fatal hemorrhage while taking ibrutinib, apixaban, and clopidogrel concomitantly. Our retrospective study observed a higher rate of major hemorrhage with combined DOAC with ibrutinib than historically reported with ibrutinib alone. This combination may be associated with increased risk of major bleeding and further prospective studies evaluating this risk are necessary.


Assuntos
Anticoagulantes , Leucemia Linfocítica Crônica de Células B , Humanos , Anticoagulantes/efeitos adversos , Leucemia Linfocítica Crônica de Células B/complicações , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Incidência , Estudos Prospectivos , Estudos Retrospectivos , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia
4.
J Subst Abuse Treat ; 119: 108141, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33138926

RESUMO

BACKGROUND AND AIMS: Research has recommended a combination of pharmacotherapy and behavioral therapy to treat opioid use disorder (OUD) or alcohol use disorder (AUD). The objective of this study was to estimate the prevalence of U.S. outpatient visits in which patients had a documented OUD or AUD and in what proportion of these visits the patient was receiving medication for OUD (MOUD) or AUD (MAUD), alone or in combination with behavioral therapy. DESIGN: Cross-sectional analysis of the National Ambulatory Medical Care Survey (NAMCS) from 2014 to 2016. SETTING: NAMCS provides national estimates based on the latest census data, for all U.S. outpatient medical visits. PARTICIPANTS/CASES: All visits involving patients aged ≥18 years with an OUD or AUD diagnosis. MEASUREMENT: Medications for OUD included buprenorphine, buprenorphine/naloxone, or naltrexone; medications for AUD included acamprosate, disulfiram, or naltrexone. We defined behavioral therapy as provision of psychosocial therapy, mental health counseling, or stress management. We also compared annualized data between 2014 and 2016 using the Chi-square test. FINDINGS: From 2014 to 2016, NAMCS recorded nearly 2.3 billion adult outpatient visits, including 17.1 million and 21.7 million visits involving patients with an OUD or AUD diagnosis, respectively. From 2014 to 2016, a decreased prevalence of annual visits involved AUD (11.7 vs. 9.9/1000, P < 0.0001), while those for OUD increased (9.3 vs. 13.3/1000, P < 0.0001). Among office visits with an OUD diagnosis, a MOUD was documented in 14.2 million (83.1%) visits and behavioral therapy was provided in 4.4 million (25.6%). Among office visits with an AUD diagnosis, an MAUD was documented in approximately 800,000 (3.6%) and behavioral therapy in 5.4 million (24.8%). CONCLUSION: These data highlight an opportunity to increase the use of MAUD and offer behavioral therapy to those with OUD and/or AUD.


Assuntos
Alcoolismo , Transtornos Relacionados ao Uso de Opioides , Adulto , Alcoolismo/tratamento farmacológico , Alcoolismo/epidemiologia , Analgésicos Opioides/uso terapêutico , Estudos Transversais , Humanos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Pacientes Ambulatoriais
5.
Acta Neuropathol Commun ; 7(1): 67, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-31039818

RESUMO

Meningiomas are the most common primary brain tumor of adults. The majority are benign (WHO grade I), with a mostly indolent course; 20% of them (WHO grade II and III) are, however, considered aggressive and require a more complex management. WHO grade II and III tumors are heterogeneous and, in some cases, can develop from a prior lower grade meningioma, although most arise de novo. Mechanisms leading to progression or implicated in de novo grade II and III tumorigenesis are poorly understood. RNA-seq was used to profile the transcriptome of grade I, II, and III meningiomas and to identify genes that may be involved in progression. Bioinformatic analyses showed that grade I meningiomas that progress to a higher grade are molecularly different from those that do not. As such, we identify GREM2, a regulator of the BMP pathway, and the snoRNAs SNORA46 and SNORA48, as being significantly reduced in meningioma progression. Additionally, our study has identified several novel fusion transcripts that are differentially present in meningiomas, with grade I tumors that did not progress presenting more fusion transcripts than all other tumors. Interestingly, our study also points to a difference in the tumor immune microenvironment that correlates with histopathological grade.


Assuntos
Progressão da Doença , Neoplasias Meníngeas/genética , Meningioma/genética , Transcriptoma , Biologia Computacional , Feminino , Humanos , Masculino , Neoplasias Meníngeas/patologia , Meningioma/patologia , Gradação de Tumores , Neurofibromina 2/genética , RNA-Seq , Microambiente Tumoral/genética
6.
Neuro Oncol ; 18(3): 417-25, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26188015

RESUMO

BACKGROUND: MRI characteristics of brain gliomas have been used to predict clinical outcome and molecular tumor characteristics. However, previously reported imaging biomarkers have not been sufficiently accurate or reproducible to enter routine clinical practice and often rely on relatively simple MRI measures. The current study leverages advanced image analysis and machine learning algorithms to identify complex and reproducible imaging patterns predictive of overall survival and molecular subtype in glioblastoma (GB). METHODS: One hundred five patients with GB were first used to extract approximately 60 diverse features from preoperative multiparametric MRIs. These imaging features were used by a machine learning algorithm to derive imaging predictors of patient survival and molecular subtype. Cross-validation ensured generalizability of these predictors to new patients. Subsequently, the predictors were evaluated in a prospective cohort of 29 new patients. RESULTS: Survival curves yielded a hazard ratio of 10.64 for predicted long versus short survivors. The overall, 3-way (long/medium/short survival) accuracy in the prospective cohort approached 80%. Classification of patients into the 4 molecular subtypes of GB achieved 76% accuracy. CONCLUSIONS: By employing machine learning techniques, we were able to demonstrate that imaging patterns are highly predictive of patient survival. Additionally, we found that GB subtypes have distinctive imaging phenotypes. These results reveal that when imaging markers related to infiltration, cell density, microvascularity, and blood-brain barrier compromise are integrated via advanced pattern analysis methods, they form very accurate predictive biomarkers. These predictive markers used solely preoperative images, hence they can significantly augment diagnosis and treatment of GB patients.


Assuntos
Neoplasias Encefálicas/patologia , Glioblastoma/mortalidade , Glioblastoma/patologia , Interpretação de Imagem Assistida por Computador , Adulto , Algoritmos , Barreira Hematoencefálica , Neoplasias Encefálicas/fisiopatologia , Estudos de Coortes , Feminino , Glioblastoma/genética , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Aprendizado de Máquina , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
7.
J Clin Invest ; 126(5): 1801-14, 2016 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-27043280

RESUMO

Aberrant vascularization is a hallmark of cancer progression and treatment resistance. Here, we have shown that endothelial cell (EC) plasticity drives aberrant vascularization and chemoresistance in glioblastoma multiforme (GBM). By utilizing human patient specimens, as well as allograft and genetic murine GBM models, we revealed that a robust endothelial plasticity in GBM allows acquisition of fibroblast transformation (also known as endothelial mesenchymal transition [Endo-MT]), which is characterized by EC expression of fibroblast markers, and determined that a prominent population of GBM-associated fibroblast-like cells have EC origin. Tumor ECs acquired the mesenchymal gene signature without the loss of EC functions, leading to enhanced cell proliferation and migration, as well as vessel permeability. Furthermore, we identified a c-Met/ETS-1/matrix metalloproteinase-14 (MMP-14) axis that controls VE-cadherin degradation, Endo-MT, and vascular abnormality. Pharmacological c-Met inhibition induced vessel normalization in patient tumor-derived ECs. Finally, EC-specific KO of Met inhibited vascular transformation, normalized blood vessels, and reduced intratumoral hypoxia, culminating in suppressed tumor growth and prolonged survival in GBM-bearing mice after temozolomide treatment. Together, these findings illustrate a mechanism that controls aberrant tumor vascularization and suggest that targeting Endo-MT may offer selective and efficient strategies for antivascular and vessel normalization therapies in GBM, and possibly other malignant tumors.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Células Endoteliais/metabolismo , Glioblastoma/irrigação sanguínea , Glioblastoma/metabolismo , Neovascularização Patológica/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Animais , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/genética , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Células Endoteliais/patologia , Feminino , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Humanos , Masculino , Metaloproteinase 14 da Matriz/genética , Metaloproteinase 14 da Matriz/metabolismo , Camundongos , Camundongos Knockout , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Proteína Proto-Oncogênica c-ets-1/genética , Proteína Proto-Oncogênica c-ets-1/metabolismo , Proteínas Proto-Oncogênicas c-met/genética , Temozolomida
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