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1.
Compr Rev Food Sci Food Saf ; 22(4): 2495-2522, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37078119

RESUMO

With the growing global population, the need for food is expected to grow tremendously in the next few decades. One of the key tools to address such growing food demand is minimizing grain losses and optimizing food processing operations. Hence, several research studies are underway to reduce grain losses/degradation at the farm (upon harvest) and later during the milling and baking processes. However, less attention has been paid to changes in grain quality between harvest and milling. This paper aims to address this knowledge gap and discusses possible strategies for preserving grain quality (for Canadian wheat in particular) during unit operations at primary, process, or terminal elevators. To this end, the importance of wheat flour quality metrics is briefly described, followed by a discussion on the effect of grain properties on such quality parameters. This work also explores how drying, storage, blending, and cleaning, as some of the common post-harvest unit operations, could affect grain's end-product quality. Finally, an overview of the available techniques for grain quality monitoring is provided, followed by a discussion on existing gaps and potential solutions for quality traceability throughout the wheat supply chain.


Assuntos
Farinha , Triticum , Canadá , Grão Comestível , Farinha/análise , Manipulação de Alimentos/métodos
2.
PLoS One ; 16(7): e0252048, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34264955

RESUMO

Neurofibromatosis Type 2 (NF2) is an autosomal dominant genetic syndrome caused by mutations in the NF2 tumor suppressor gene resulting in multiple schwannomas and meningiomas. There are no FDA approved therapies for these tumors and their relentless progression results in high rates of morbidity and mortality. Through a combination of high throughput screens, preclinical in vivo modeling, and evaluation of the kinome en masse, we identified actionable drug targets and efficacious experimental therapeutics for the treatment of NF2 related schwannomas and meningiomas. These efforts identified brigatinib (ALUNBRIG®), an FDA-approved inhibitor of multiple tyrosine kinases including ALK, to be a potent inhibitor of tumor growth in established NF2 deficient xenograft meningiomas and a genetically engineered murine model of spontaneous NF2 schwannomas. Surprisingly, neither meningioma nor schwannoma cells express ALK. Instead, we demonstrate that brigatinib inhibited multiple tyrosine kinases, including EphA2, Fer and focal adhesion kinase 1 (FAK1). These data demonstrate the power of the de novo unbiased approach for drug discovery and represents a major step forward in the advancement of therapeutics for the treatment of NF2 related malignancies.


Assuntos
Neoplasias Meníngeas/genética , Meningioma/genética , Neurilemoma/genética , Neurofibromina 2/deficiência , Neurofibromina 2/genética , Compostos Organofosforados/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirimidinas/farmacologia , Proliferação de Células , Humanos , Mutação , Neurilemoma/patologia
3.
Hum Mol Genet ; 30(17): 1607-1617, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34075397

RESUMO

Neurofibromatosis Type II (NF2) is an autosomal dominant cancer predisposition syndrome in which germline haploinsufficiency at the NF2 gene confers a greatly increased propensity for tumor development arising from tissues of neural crest derived origin. NF2 encodes the tumor suppressor, Merlin, and its biochemical function is incompletely understood. One well-established function of Merlin is as a negative regulator of group A serine/threonine p21-activated kinases (PAKs). In these studies we explore the role of PAK1 and its closely related paralog, PAK2, both pharmacologically and genetically, in Merlin-deficient Schwann cells and in a genetically engineered mouse model (GEMM) that develops spontaneous vestibular and spinal schwannomas. We demonstrate that PAK1 and PAK2 are both hyper activated in Merlin-deficient murine schwannomas. In preclinical trials, a pan Group A PAK inhibitor, FRAX-1036, transiently reduced PAK1 and PAK2 phosphorylation in vitro, but had insignificant efficacy in vivo. NVS-PAK1-1, a PAK1 selective inhibitor, had a greater but still minimal effect on our GEMM phenotype. However, genetic ablation of Pak1 but not Pak2 reduced tumor formation in our NF2 GEMM. Moreover, germline genetic deletion of Pak1 was well tolerated, while conditional deletion of Pak2 in Schwann cells resulted in significant morbidity and mortality. These data support the further development of PAK1-specific small molecule inhibitors and the therapeutic targeting of PAK1 in vestibular schwannomas and argue against PAK1 and PAK2 existing as functionally redundant protein isoforms in Schwann cells.


Assuntos
Neurofibromatose 2/genética , Quinases Ativadas por p21/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Genes Supressores de Tumor/efeitos dos fármacos , Indóis , Longevidade , Camundongos , Neurilemoma/genética , Neurofibromatose 2/metabolismo , Neurofibromina 2/genética , Fosforilação , Piperidinas , Pirimidinas , Células de Schwann/metabolismo , Quinases Ativadas por p21/genética
5.
JCI Insight ; 5(20)2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32960816

RESUMO

Schwannomas are tumors of the Schwann cells that cause chronic pain, numbness, and potentially life-threatening impairment of vital organs. Despite the identification of causative genes, including NF2 (Merlin), INI1/SMARCB1, and LZTR1, the exact molecular mechanism of schwannoma development is still poorly understood. Several studies have identified Merlin as a key regulator of the Hippo, MAPK, and PI3K signaling pathways; however, definitive evidence demonstrating the importance of these pathways in schwannoma pathogenesis is absent. Here, we provide direct genetic evidence that dysregulation of the Hippo pathway in the Schwann cell lineage causes development of multiple schwannomas in mice. We found that canonical Hippo signaling through the effectors YAP/TAZ is required for schwannomagenesis and that MAPK signaling modifies schwannoma formation. Furthermore, cotargeting YAP/TAZ transcriptional activity and MAPK signaling demonstrated a synergistic therapeutic effect on schwannomas. Our new model provides a tractable platform to dissect the molecular mechanisms underpinning schwannoma formation and the role of combinatorial targeted therapy in schwannoma treatment.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Perda de Heterozigosidade/genética , Neurilemoma/genética , Neurofibromina 2/genética , Animais , Regulação Neoplásica da Expressão Gênica/genética , Fator de Crescimento de Hepatócito/genética , Humanos , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Neurilemoma/patologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Proteína SMARCB1/genética , Transdução de Sinais/genética , Fatores de Transcrição/genética , Proteínas de Sinalização YAP , Proteínas ras/genética
6.
Arthritis Res Ther ; 22(1): 106, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32381123

RESUMO

BACKGROUND: The tumor necrosis factor (TNF) superfamily cytokine TNF-like protein 1A (TL1A) and its receptor DR3 are essential for diverse animal models of autoimmune disease and may be pathogenic in rheumatoid arthritis (RA). However, the relationship of TL1A to disease duration, activity, and response to anti-TNF and other therapies in RA is not clear. METHODS: We measured soluble TL1A in synovial fluid (SF), serum, or plasma from RA first-degree relatives (FDRs) and in early RA and established disease. We measured the effects of anti-TNF and methotrexate (MTX) therapy on circulating TL1A from multiple independent RA treatment trials. We also determined the ability of a blocking anti-TL1A antibody to inhibit clinical disease and articular bone destruction in the murine collagen-induced arthritis (CIA) model of human RA. RESULTS: Soluble TL1A was specifically elevated in the blood and SF of patients with RA compared to patients with other diseases and was elevated early in disease and in at-risk anti-cyclic citrullinated peptide (CCP) (+) first-degree relatives (FDRs). Therapeutic TNF inhibition reduced serum TL1A in both responders and non-responders, whereas TL1A declined following MTX treatment only in responders. In murine CIA, TL1A blockade was clinically efficacious and reduced bone erosions. CONCLUSIONS: TL1A is specifically elevated in RA from early in the disease course and in at-risk FDRs. The decline in TL1A after TNF blockade suggests that TL1A levels may be a useful biomarker for TNF activity in RA. These results support the further investigation of the relationship between TL1A and TNF and TL1A blockade as a potential therapeutic strategy in RA.


Assuntos
Artrite Experimental , Artrite Reumatoide , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/sangue , Animais , Artrite Experimental/tratamento farmacológico , Artrite Experimental/genética , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/genética , Humanos , Metotrexato/uso terapêutico , Camundongos , Líquido Sinovial , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/antagonistas & inibidores , Fator de Necrose Tumoral alfa
7.
J Biol Chem ; 295(29): 9948-9958, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32471868

RESUMO

Neurofibromatosis type 1 (NF1) is a common cancer predisposition syndrome caused by mutations in the NF1 tumor suppressor gene. NF1 encodes neurofibromin, a GTPase-activating protein for RAS proto-oncogene GTPase (RAS). Plexiform neurofibromas are a hallmark of NF1 and result from loss of heterozygosity of NF1 in Schwann cells, leading to constitutively activated p21RAS. Given the inability to target p21RAS directly, here we performed an shRNA library screen of all human kinases and Rho-GTPases in a patient-derived NF1-/- Schwann cell line to identify novel therapeutic targets to disrupt PN formation and progression. Rho family members, including Rac family small GTPase 1 (RAC1), were identified as candidates. Corroborating these findings, we observed that shRNA-mediated knockdown of RAC1 reduces cell proliferation and phosphorylation of extracellular signal-regulated kinase (ERK) in NF1-/- Schwann cells. Genetically engineered Nf1flox/flox;PostnCre+ mice, which develop multiple PNs, also exhibited increased RAC1-GTP and phospho-ERK levels compared with Nf1flox/flox;PostnCre- littermates. Notably, mice in which both Nf1 and Rac1 loci were disrupted (Nf1flox/floxRac1flox/flox;PostnCre+) were completely free of tumors and had normal phospho-ERK activity compared with Nf1flox/flox ;PostnCre+ mice. We conclude that the RAC1-GTPase is a key downstream node of RAS and that genetic disruption of the Rac1 allele completely prevents PN tumor formation in vivo in mice.


Assuntos
Técnicas de Silenciamento de Genes , Segunda Neoplasia Primária , Neurofibroma Plexiforme , Neurofibromatose 1 , Neuropeptídeos/deficiência , Proteínas rac1 de Ligação ao GTP/deficiência , Animais , Camundongos , Camundongos Knockout , Segunda Neoplasia Primária/enzimologia , Segunda Neoplasia Primária/genética , Segunda Neoplasia Primária/patologia , Segunda Neoplasia Primária/prevenção & controle , Neurofibroma Plexiforme/enzimologia , Neurofibroma Plexiforme/genética , Neurofibroma Plexiforme/prevenção & controle , Neurofibromatose 1/enzimologia , Neurofibromatose 1/genética , Neurofibromatose 1/patologia , Neurofibromina 1/deficiência , Neurofibromina 1/metabolismo , Neuropeptídeos/metabolismo , Proto-Oncogene Mas , Proteínas rac1 de Ligação ao GTP/metabolismo
8.
Mol Cancer Ther ; 18(12): 2321-2330, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31527226

RESUMO

Neurofibromatosis Type 1 (NF1) is one of the most common genetic tumor predisposition syndromes in humans. Mutant NF1 results in dysregulated RAS allowing neoplasms throughout the neuroaxis. Plexiform neurofibromas (pNF) afflict up to 50% of patients with NF1. They are complex tumors of the peripheral nerve that cause major morbidity via nerve dysregulation and mortality via conversion to malignant sarcoma. Genetically engineered mouse models (GEMM) of NF1 provide valuable insights for the identification of therapies that have utility in people with pNF. Preclinical studies in GEMMs implicate mast cells and the c-Kit/Kit ligand pathway in pNF tumorigenesis. Kit ligand is a potent chemokine secreted by tumorigenic, Nf1-deficient Schwann cells. Ketotifen is an FDA-approved drug for the treatment of allergic conjunctivitis and asthma that promotes mast cell stabilization and has been used in prior case studies to treat or prevent pNFs. This study investigated the effect of ketotifen on mast cell infiltration and degranulation in the presence and absence of Kit ligand provocation and the effect of ketotifen on shrinking or preventing pNF formation in the Nf1flox/flox ;PostnCre + GEMM. Ketotifen decreased mast cell infiltration in response to exogenous Kit ligand administration, but did not affect mast cell degranulation. Importantly, ketotifen did not reduce mast cells numbers or activity in pNF and did not prevent pNF formation or decrease the volume of established pNF despite administration of pharmacologically active doses. These findings suggest that ketotifen has limited use as monotherapy to prevent or reduce pNF burden in the setting of Nf1 mutations.


Assuntos
Quimiotaxia/fisiologia , Antagonistas dos Receptores Histamínicos H1/uso terapêutico , Cetotifeno/uso terapêutico , Mastócitos/efeitos dos fármacos , Neurofibroma/genética , Neurofibromina 1/deficiência , Animais , Antagonistas dos Receptores Histamínicos H1/farmacologia , Cetotifeno/farmacologia , Camundongos , Fator de Células-Tronco
9.
Hum Mol Genet ; 28(4): 572-583, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30335132

RESUMO

Schwannomas are common, highly morbid and medically untreatable tumors that can arise in patients with germ line as well as somatic mutations in neurofibromatosis type 2 (NF2). These mutations most commonly result in the loss of function of the NF2-encoded protein, Merlin. Little is known about how Merlin functions endogenously as a tumor suppressor and how its loss leads to oncogenic transformation in Schwann cells (SCs). Here, we identify nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)-inducing kinase (NIK) as a potential drug target driving NF-κB signaling and Merlin-deficient schwannoma genesis. Using a genomic approach to profile aberrant tumor signaling pathways, we describe multiple upregulated NF-κB signaling elements in human and murine schwannomas, leading us to identify a caspase-cleaved, proteasome-resistant NIK kinase domain fragment that amplifies pathogenic NF-κB signaling. Lentiviral-mediated transduction of this NIK fragment into normal SCs promotes proliferation, survival, and adhesion while inducing schwannoma formation in a novel in vivo orthotopic transplant model. Furthermore, we describe an NF-κB-potentiated hepatocyte growth factor (HGF) to MET proto-oncogene receptor tyrosine kinase (c-Met) autocrine feed-forward loop promoting SC proliferation. These innovative studies identify a novel signaling axis underlying schwannoma formation, revealing new and potentially druggable schwannoma vulnerabilities with future therapeutic potential.


Assuntos
Neurilemoma/genética , Neurofibromatose 2/genética , Neurofibromina 2/genética , Proteínas Serina-Treonina Quinases/genética , Animais , Comunicação Autócrina/genética , Carcinogênese/genética , Caspase 1/genética , Proliferação de Células/genética , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Fator de Crescimento de Hepatócito/genética , Humanos , Camundongos , Terapia de Alvo Molecular , NF-kappa B/genética , Neurilemoma/complicações , Neurilemoma/tratamento farmacológico , Neurilemoma/patologia , Neurofibromatose 2/complicações , Neurofibromatose 2/tratamento farmacológico , Neurofibromatose 2/patologia , Complexo de Endopeptidases do Proteassoma/genética , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-met/genética , Células de Schwann , Transdução de Sinais/genética , Quinase Induzida por NF-kappaB
10.
PLoS Genet ; 14(9): e1007458, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30199539

RESUMO

Chronic inflammation in inflammatory bowel disease (IBD) results from a breakdown of intestinal immune homeostasis and compromise of the intestinal barrier. Genome-wide association studies have identified over 200 genetic loci associated with risk for IBD, but the functional mechanisms of most of these genetic variants remain unknown. Polymorphisms at the TNFSF15 locus, which encodes the TNF superfamily cytokine commonly known as TL1A, are associated with susceptibility to IBD in multiple ethnic groups. In a wide variety of murine models of inflammation including models of IBD, TNFSF15 promotes immunopathology by signaling through its receptor DR3. Such evidence has led to the hypothesis that expression of this lymphocyte costimulatory cytokine increases risk for IBD. In contrast, here we show that the IBD-risk haplotype at TNFSF15 is associated with decreased expression of the gene by peripheral blood monocytes in both healthy volunteers and IBD patients. This association persists under various stimulation conditions at both the RNA and protein levels and is maintained after macrophage differentiation. Utilizing a "recall-by-genotype" bioresource for allele-specific expression measurements in a functional fine-mapping assay, we localize the polymorphism controlling TNFSF15 expression to the regulatory region upstream of the gene. Through a T cell costimulation assay, we demonstrate that genetically regulated TNFSF15 has functional relevance. These findings indicate that genetically enhanced expression of TNFSF15 in specific cell types may confer protection against the development of IBD.


Assuntos
Colite Ulcerativa/genética , Doença de Crohn/genética , Predisposição Genética para Doença , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Adulto , Alelos , Células Cultivadas , Colite Ulcerativa/sangue , Colite Ulcerativa/imunologia , Doença de Crohn/sangue , Doença de Crohn/imunologia , Feminino , Haplótipos/genética , Humanos , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Cultura Primária de Células , Locos de Características Quantitativas/imunologia , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/sangue , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Adulto Jovem
11.
Oncotarget ; 9(1): 718-725, 2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-29416648

RESUMO

Mutations in the tumor suppressor gene NF2 lead to Neurofibromatosis type 2 (NF2), a tumor predisposition syndrome characterized by the development of schwannomas, including bilateral vestibular schwannomas with complete penetrance. Recent work has implicated the importance of COX-2 in schwannoma growth. Using a genetically engineered murine model of NF2, we demonstrate that selective inhibition of COX-2 with celecoxib fails to prevent the spontaneous development of schwannomas or sensorineural hearing loss in vivo, despite elevated expression levels of COX-2 in Nf2-deficient tumor tissue. These results suggest that COX-2 is nonessential to schwannomagenesis and that the proposed tumor suppressive effects of NSAIDs on schwannomas may occur through COX-2 independent mechanisms.

13.
J Immunol ; 194(8): 3567-82, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25786692

RESUMO

The TNF family cytokine TL1A (Tnfsf15) costimulates T cells and type 2 innate lymphocytes (ILC2) through its receptor DR3 (Tnfrsf25). DR3-deficient mice have reduced T cell accumulation at the site of inflammation and reduced ILC2-dependent immune responses in a number of models of autoimmune and allergic diseases. In allergic lung disease models, immunopathology and local Th2 and ILC2 accumulation is reduced in DR3-deficient mice despite normal systemic priming of Th2 responses and generation of T cells secreting IL-13 and IL-4, prompting the question of whether TL1A promotes the development of other T cell subsets that secrete cytokines to drive allergic disease. In this study, we find that TL1A potently promotes generation of murine T cells producing IL-9 (Th9) by signaling through DR3 in a cell-intrinsic manner. TL1A enhances Th9 differentiation through an IL-2 and STAT5-dependent mechanism, unlike the TNF-family member OX40, which promotes Th9 through IL-4 and STAT6. Th9 differentiated in the presence of TL1A are more pathogenic, and endogenous TL1A signaling through DR3 on T cells is required for maximal pathology and IL-9 production in allergic lung inflammation. Taken together, these data identify TL1A-DR3 interactions as a novel pathway that promotes Th9 differentiation and pathogenicity. TL1A may be a potential therapeutic target in diseases dependent on IL-9.


Assuntos
Asma/imunologia , Diferenciação Celular/imunologia , Interleucina-9/imunologia , Membro 25 de Receptores de Fatores de Necrose Tumoral/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologia , Animais , Asma/genética , Asma/patologia , Diferenciação Celular/genética , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Interleucina-13/genética , Interleucina-13/imunologia , Interleucina-4/genética , Interleucina-4/imunologia , Interleucina-9/genética , Camundongos , Camundongos Knockout , Membro 25 de Receptores de Fatores de Necrose Tumoral/genética , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Linfócitos T Auxiliares-Indutores/patologia , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética
14.
Gene ; 502(2): 108-17, 2012 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-22521866

RESUMO

The 5-HT(2C) receptor is one of 14 different serotonin (5-HT) receptors that control neural function and behavior. Here, we present the entire sequence of a zebrafish 5-HT(2C) receptor cDNA including the 3' untranslated region and the previously unknown 5' untranslated region. The cloned 5-HT(2C) receptor gene is located on chromosome 7, is approximately 202 kbp long, and contains six exons. The coding region of the gene is 1557 bp long and flanked by a 504 bp 5' UTR and a 1474 bp 3' UTR. The deduced protein sequence of 518 amino acids aligns with orthologs of other vertebrates and is 54% identical to the human and mouse 5-HT(2C) receptor protein sequences. The region of the cDNA that encodes the 2nd cytoplasmic loop of the protein shows a 66% identity with vertebrate orthologs and clearly identifies the gene as a 5-HT(2C) receptor gene. Coupling sites for beta-arrestin and calmodulin are conserved in zebrafish. In-situ hybridization shows that the receptor is expressed in the brain and spinal cord including areas such as the olfactory bulb, the dorsal thalamus, the posterior tuberculum, the hypothalamus and the medulla oblongata. Reverse Transcriptase-PCR experiments indicate that the receptor gene can also be active in other tissues such as skin, ovaries, and axial muscle of adult zebrafish. Expression of the 5-HT(2C) receptor during ontogeny was found as early as 2.5 hpf. Five edited adenines in the region of the human, rat and mouse mRNA that encodes the 2nd cytoplasmic loop are conserved in the zebrafish transcript. However, RNA editing was not detected in the zebrafish. The results characterize the zebrafish 5-HT(2C) receptor gene and gene expression pattern for the first time. The similarities to mammalian 5-HT(2C) receptor genes suggest the use of zebrafish for the study of 5-HT(2C) receptor function in behavior, development and drug discovery.


Assuntos
Receptor 5-HT2C de Serotonina/biossíntese , Receptor 5-HT2C de Serotonina/genética , Peixe-Zebra/genética , Regiões 3' não Traduzidas , Regiões 5' não Traduzidas , Sequência de Aminoácidos , Animais , Arrestinas/genética , Sequência de Bases , Encéfalo/metabolismo , Clonagem Molecular/métodos , DNA Complementar/genética , Expressão Gênica , Humanos , Camundongos , Dados de Sequência Molecular , Edição de RNA/genética , RNA Mensageiro/genética , Ratos , Homologia de Sequência de Aminoácidos , Medula Espinal/metabolismo , beta-Arrestinas
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