Pi3k Inhibition Synergizes With Glucocorticoids But Antagonizes With Methotrexate In T-cell Acute Lymphoblastic Leukemia.

The PI3K pathway is frequently hyperactivated in primary T-cell acute lymphoblastic leukemia (T-ALL) cells. Activation of the PI3K pathway has been suggested as one mechanism of glucocorticoid resistance in T-ALL, and patients harboring mutations in the PI3K negative regulator PTEN may be at increased risk of induction failure and relapse. By gene expression microarray analysis of T-ALL cells treated with the PI3K inhibitor AS605240, we identified Myc as a prominent downstream target of the PI3K pathway. A significant association was found between the AS605240 gene expression signature and that of glucocorticoid resistance and relapse in T-ALL. AS605240 showed anti-leukemic activity and strong synergism with glucocorticoids both in vitro and in a NOD/SCID xenograft model of T-ALL. In contrast, PI3K inhibition showed antagonism with methotrexate and daunorubicin, drugs that preferentially target dividing cells. This antagonistic interaction, however, could be circumvented by the use of correct drug scheduling schemes. Our data indicate the potential benefits and difficulties for the incorporation of PI3K inhibitors in T-ALL therapy.613105-1311

Identification of mutations functionally associated with IL7R'alpha' mutant in T-ALL

Orientador: José Andrés YunesTese (doutorado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: A leucemia linfóide aguda de células T (LLA-T) é uma malignidade derivada da transformação de precursores linfoblásticos e representa de 10 a 15% dos casos de LLA infantil. O paciente com LLA-T tende a apresentar-se ao diagnóstico com uma contagem muito alta de blastos circulantes, massa mediastinal e envolvimento do sistema nervoso central. O prognóstico das crianças e adolescentes com LLA-T tem melhorado muito nos últimos anos. Entretanto alguns casos ainda recaem durante a terapia ou dentro dos primeiros dois anos após o tratamento da doença e eventualmente vão a óbito. Avanços metodológicos permitiram maior entendimento das alterações genéticas subjacentes à LLA-T. A sinalização mediada por IL7/IL7R é essencial para a homeostase e o desenvolvimento normal dos precursores de células T. Cerca de 10% dos pacientes com LLA-T pediátrica, apresentam mutações na cadeia alfa do receptor para a interleucina 7 (IL7R'alfa'), que levam à ativação constitutiva desta proteína e consequentemente à proliferação descontrolada destas células. Algumas alterações genéticas constituem importantes fatores para iniciar a leucemia, mas em muitos casos estas alterações são insuficientes para formar um fenótipo leucêmico completo, sugerindo a necessidade de mutações oncogênicas colaborativas. Com o objetivo de identificar possíveis mutações colaborativas ao IL7R oncogênico, nós investigamos o perfil mutacional de nove casos de LLA-T pediátrica com IL7R mutante, através do sequenciamento do exoma e microarranjo de SNP/CNV utilizando amostras pareadas Diagnóstico x Remissão. Os resultados demonstram associação estatisticamente significativa entre IL7R mutado e alterações no gene PHF6, sugerindo que esses dois genes devem contribuir para LLA-T de forma colaborativa. Alterações na via de sinalização WNT também foi evidenciada como uma via potencialmente colaborativa ao IL7R oncogênico. Além disso, a pseudo-quinase SGK223 está sendo descrita neste trabalho pela a primeira vez como gene potencialmente implicado no desenvolvimento da LLA-T pelo menos nos casos portadores do IL7R mutante. Juntos os resultados fornecem entendimento sobre o panorama de alterações genéticas dos casos de LLA-T portadores da mutação IL7RAbstract: A leucemia linfóide aguda de células T (LLA-T) é uma malignidade derivada da transformação de precursores linfoblásticos e representa de 10 a 15% dos casos de LLA infantil. O paciente com LLA-T tende a apresentar-se ao diagnóstico com uma contagem muito alta de blastos circulantes, massa mediastinal e envolvimento do sistema nervoso central. O prognóstico das crianças e adolescentes com LLA-T tem melhorado muito nos últimos anos. Entretanto alguns casos ainda recaem durante a terapia ou dentro dos primeiros dois anos após o tratamento da doença e eventualmente vão a óbito. Avanços metodológicos permitiram maior entendimento das alterações genéticas subjacentes à LLA-T. A sinalização mediada por IL7/IL7R é essencial para a homeostase e o desenvolvimento normal dos precursores de células T. Cerca de 10% dos pacientes com LLA-T pediátrica, apresentam mutações na cadeia alfa do receptor para a interleucina 7 (IL7R'alpha'), que levam à ativação constitutiva desta proteína e consequentemente à proliferação descontrolada destas células. Algumas alterações genéticas constituem importantes fatores para iniciar a leucemia, mas em muitos casos estas alterações são insuficientes para formar um fenótipo leucêmico completo, sugerindo a necessidade de mutações oncogênicas colaborativas. Com o objetivo de identificar possíveis mutações colaborativas ao IL7R oncogênico, nós investigamos o perfil mutacional de nove casos de LLA-T pediátrica com IL7R mutante, através do sequenciamento do exoma e microarranjo de SNP/CNV utilizando amostras pareadas Diagnóstico x Remissão. Os resultados demonstram associação estatisticamente significativa entre IL7R mutado e alterações no gene PHF6, sugerindo que esses dois genes devem contribuir para LLA-T de forma colaborativa. Alterações na via de sinalização WNT também foi evidenciada como uma via potencialmente colaborativa ao IL7R oncogênico. Além disso, a pseudo-quinase SGK223 está sendo descrita neste trabalho pela a primeira vez como gene potencialmente implicado no desenvolvimento da LLA-T pelo menos nos casos portadores do IL7R mutante. Juntos os resultados fornecem entendimento sobre o panorama de alterações genéticas dos casos de LLA-T portadores da mutação IL7RDoutoradoGenetica Animal e EvoluçãoDoutora em Genética e Biologia Molecular2012/10284-3FAPES

Oncogenic basic amino acid insertions at the extracellular juxtamembrane region of IL7Rα cause receptor hypersensitivity

sem informação1331112591263CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP305896/2013-0; 301596/2017-4sem informação12/12802-1; 14/20015-5; 10/16947-9; 13/08293-7Fundacao de Amparo a Pesquisa do Estado de Sao PauloFundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [12/12802-1, 14/20015-5, 10/16947-9, 13/08293-7]; National Health and Medical Research Council of AustraliaNational Health and Medical Research Council of Australia [APP1084797]; Fundacao de Amparo a Pesquisa do Estado de Sao PauloFundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP); Coordenacao de Aperfeicoamento de Pessoal de Nivel SuperiorCAPES; Brazilian National Counsel of Technological and Scientific Development (CNPq)National Council for Scientific and Technological Development (CNPq) [305896/2013-0, 301596/2017-4

CAISMOV24, a new human low-grade serous ovarian carcinoma cell line

Abstract Background The spontaneous immortalization of primary malignant cells is frequently assigned to their genetic instability during in vitro culturing. In this study, the new epithelial ovarian cancer cell line CAISMOV24 was described and compared with its original low-grade serous ovarian carcinoma. Methods The in vitro culture was established with cells isolated from ascites of a 60-year-old female patient with recurrent ovarian cancer. The CAISMOV24 line was assessed for cell growth, production of soluble biomarkers, expression of surface molecules and screened for typical mutations found in serous ovarian carcinoma. Additionally, comparative genomic hybridization was employed to compare genomic alterations between the CAISMOV24 cell line and its primary malignant cells. Results CAISMOV24 has been in continuous culture for more than 30 months and more than 100 in vitro passages. The cell surface molecules EpCAM, PVR and CD73 are overexpressed on CAISMOV24 cells compared to the primary malignant cells. CAISMOV24 continues to produce CA125 and HE4 in vitro. Although the cell line had developed alongside the accumulation of genomic alterations (28 CNV in primary cells and 37 CNV in CAISMOV24), most of them were related to CNVs already present in primary malignant cells. CAISMOV24 cell line harbored KRAS mutation with wild type TP53, therefore it is characterized as low-grade serous carcinoma. Conclusion Our results corroborate with the idea that genomic alterations, depicted by CNVs, can be used for subtyping epithelial ovarian carcinomas. Additionally, CAISMOV24 cell line was characterized as a low-grade serous ovarian carcinoma, which still resembles its primary malignant cells

PI3K inhibition synergizes with glucocorticoids but antagonizes with methotrexate in T-cell acute lymphoblastic leukemia

The PI3K pathway is frequently hyperactivated in primary T-cell acute lymphoblastic leukemia (T-ALL) cells. Activation of the PI3K pathway has been suggested as one mechanism of glucocorticoid resistance in T-ALL, and patients harboring mutations in the PI3K negative regulator PTEN may be at increased risk of induction failure and relapse. By gene expression microarray analysis of T-ALL cells treated with the PI3K inhibitor AS605240, we identified Myc as a prominent downstream target of the PI3K pathway. A significant association was found between the AS605240 gene expression signature and that of glucocorticoid resistance and relapse in T-ALL. AS605240 showed anti-leukemic activity and strong synergism with glucocorticoids both in vitro and in a NOD/SCID xenograft model of T-ALL. In contrast, PI3K inhibition showed antagonism with methotrexate and daunorubicin, drugs that preferentially target dividing cells. This antagonistic interaction, however, could be circumvented by the use of correct drug scheduling schemes. Our data indicate the potential benefits and difficulties for the incorporation of PI3K inhibitors in T-ALL therapy6151310513118CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPSem informação08/10034–

Nucleoside Analogs with Selective Antiviral Activity against Dengue Fever and Japanese Encephalitis Viruses

Dengue virus (DENV) and Japanese encephalitis virus (JEV) are important arthropod-borne viruses from the Flaviviridae family. DENV is a global public health problem with significant social and economic impacts, especially in tropical and subtropical areas. JEV is a neurotropic arbovirus endemic to east and southeast Asia. There are no U.S. FDA-approved antiviral drugs available to treat or to prevent DENV and JEV infections, leaving nearly one-third of the world’s population at risk for infection. Therefore, it is crucial to discover potent antiviral agents against these viruses. Nucleoside analogs, as a class, are widely used for the treatment of viral infections. In this study, we discovered nucleoside analogs that possess potent and selective anti-JEV and anti-DENV activities across all serotypes in cell-based assay systems. Both viruses were susceptible to sugar-substituted 2=-C-methyl analogs with either cytosine or 7-deaza-7-fluoro-adenine nucleobases. Mouse studies confirmed the anti-DENV activity of these nucleoside analogs. Molecular models were assembled for DENV serotype 2 (DENV-2) and JEV RNA-dependent RNA polymerase replication complexes bound to nucleotide inhibitors. These models show similarities between JEV and DENV-2, which recognize the same nucleotide inhibitors. Collectively, our findings provide promising compounds and a structural rationale for the development of direct-acting antiviral agents with dual activity against JEV and DENV infections

Targeting the Annexin A1-FPR2/ALX pathway for host-directed therapy in dengue disease

Host immune responses contribute to dengue’s pathogenesis and severity, yet the possibility that failure in endogenous inflammation resolution pathways could characterise the disease has not been contemplated. The pro-resolving protein Annexin A1 (AnxA1) is known to counterbalance overexuberant inflammation and mast cell (MC) activation. We hypothesised that inadequate AnxA1 engagement underlies the cytokine storm and vascular pathologies associated with dengue disease. Levels of AnxA1 were examined in the plasma of dengue patients and infected mice. Immunocompetent, interferon (alpha and beta) receptor one knockout (KO), AnxA1 KO, and formyl peptide receptor 2 (FPR2) KO mice were infected with dengue virus (DENV) and treated with the AnxA1 mimetic peptide Ac2-26 for analysis. In addition, the effect of Ac2-26 on DENV-induced MC degranulation was assessed in vitro and in vivo. We observed that circulating levels of AnxA1 were reduced in dengue patients and DENV-infected mice. Whilst the absence of AnxA1 or its receptor FPR2 aggravated illness in infected mice, treatment with AnxA1 agonistic peptide attenuated disease manifestationsatteanuated the symptoms of the disease. Both clinical outcomes were attributed to modulation of DENV-mediated viral load-independent MC degranulation. We have thereby identified that altered levels of the pro-resolving mediator AnxA1 are of pathological relevance in DENV infection, suggesting FPR2/ALX agonists as a therapeutic target for dengue disease