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1.
Methods Cell Biol ; 185: 35-48, 2024.
Article in English | MEDLINE | ID: mdl-38556450

ABSTRACT

Childhood cancer is a major cause of death in developed countries, and while treatments and survival rates have improved, long-term side effects remain a challenge. The genetic component of pediatric tumors and their aggressive progression, makes the study of childhood cancer a complex area of research. Here, we introduce the fruit fly Drosophila melanogaster as study model. We emphasize its numerous advantages, including binary gene expression systems that enable precise control over the timing and location of gene expression manipulation, the capacity to combine multiple genes associated with cancer or the testing of human cancer variants within a live, intact animal. As an illustrative example, we focus on the Drosophila cancer paradigm which involves medically relevant genes, the Notch and PI3K/Akt signaling pathways. We describe how this cancer paradigm allows assessing two critical aspects of tumorigenesis during juvenile stages: (1) viability (do animals with particular cancer mutations survive into adulthood?), and (2) tumor burden (what percentage of animals bearing the cancer mutations actually develop cancer and what is the extent of the tumor?). We highlight the potential of Drosophila as a molecular therapeutic tool for drug screening and drug repurposing of medicines already approved to treat other diseases in children, thereby accelerating the potential translation of results into humans. This preclinical animal model sustains huge potential and is cost-effective. It allows screening of thousands of compounds and genes at a relatively low cost and human efforts, opening innovative venues to explore more effective and safer treatments of childhood cancer.


Subject(s)
Drosophila melanogaster , Neoplasms , Child , Animals , Humans , Drosophila melanogaster/genetics , Drosophila melanogaster/metabolism , Neoplasms/drug therapy , Neoplasms/genetics , Neoplasms/pathology , Phosphatidylinositol 3-Kinases/metabolism , Drosophila , Models, Animal
2.
Cells ; 10(11)2021 11 17.
Article in English | MEDLINE | ID: mdl-34831432

ABSTRACT

Both in situ and allograft models of cancer in juvenile and adult Drosophila melanogaster fruit flies offer a powerful means for unravelling cancer gene networks and cancer-host interactions. They can also be used as tools for cost-effective drug discovery and repurposing. Moreover, in situ modeling of emerging tumors makes it possible to address cancer initiating events-a black box in cancer research, tackle the innate antitumor immune responses to incipient preneoplastic cells and recurrent growing tumors, and decipher the initiation and evolution of inflammation. These studies in Drosophila melanogaster can serve as a blueprint for studies in more complex organisms and help in the design of mechanism-based therapies for the individualized treatment of cancer diseases in humans. This review focuses on new discoveries in Drosophila related to the diverse innate immune responses to cancer-related inflammation and the systemic effects that are so detrimental to the host.


Subject(s)
Host-Pathogen Interactions/immunology , Immunity, Innate , Inflammation/immunology , Inflammation/pathology , Neoplasms/immunology , Neoplasms/pathology , Animals , Diet , Humans , Tumor Microenvironment/immunology
3.
Cannabis Cannabinoid Res ; 6(2): 148-155, 2021 04.
Article in English | MEDLINE | ID: mdl-33912679

ABSTRACT

Background: We previously reported that cannabidiol (CBD), a cannabinoid with a low toxicity profile, downregulated the expression of the prometastatic gene inhibitor of DNA binding 1 (ID1) in cancer cells, leading to inhibition of tumor progression in vivo. While CBD is broadly used, including in the self-medication of cancer patients, and CBD-based therapies are undergoing clinical evaluation for cancer treatment, its mechanisms of action are still poorly understood. Methods: In this study, using microarray analysis and Western blot analysis for validation, we attempted to identify the full spectrum of genes regulated by CBD across various aggressive cancer cell lines, including the breast, brain, head and neck, and prostate. Results: We confirmed that ID1 was a major target downregulated by CBD and also discovered that CBD inhibited FOXM1 (Forkhead box M1), a transcriptional activator involved in cell proliferation, while simultaneously upregulating GDF15 (growth differentiation factor 15), a cytokine associated with tissue differentiation. Conclusion: Our results suggest that, by modulating expression of shared key cancer-driving genes, CBD could represent a promising nontoxic therapeutic for treating tumors of various origins.


Subject(s)
Cannabidiol , Gene Expression Regulation, Neoplastic , Neoplasms , Cannabidiol/pharmacology , Cell Line, Tumor , Cell Proliferation , Gene Expression , Humans , Male , Neoplasms/drug therapy , Oncogenes
4.
Nat Commun ; 10(1): 5017, 2019 11 01.
Article in English | MEDLINE | ID: mdl-31676756

ABSTRACT

Autophagy is an intracellular catabolic process prominent in starvation, aging and disease. Neuronal autophagy is particularly important, as it affects the development and function of the nervous system, and is heavily implicated in neurodegenerative disease. Nonetheless, how autophagy is regulated in neurons remains poorly understood. Using an unbiased proteomics approach, we demonstrate that the primary initiator of autophagy, the UNC-51/ULK kinase, is negatively regulated by the ubiquitin ligase RPM-1. RPM-1 ubiquitin ligase activity restricts UNC-51 and autophagosome formation within specific axonal compartments, and exerts effects broadly across the nervous system. By restraining UNC-51 activity, RPM-1 inhibits autophagosome formation to affect axon termination, synapse maintenance and behavioral habituation. These results demonstrate how UNC-51 and autophagy are regulated subcellularly in axons, and unveils a mechanism for restricting initiation of autophagy across the nervous system. Our findings have important implications beyond nervous system development, given growing links between altered autophagy regulation and neurodegenerative diseases.


Subject(s)
Autophagy/physiology , Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans/metabolism , Guanine Nucleotide Exchange Factors/metabolism , Neurodegenerative Diseases/metabolism , Neurons/metabolism , Ubiquitin-Protein Ligases/metabolism , Animals , Animals, Genetically Modified , Autophagosomes/metabolism , Autophagy/genetics , Autophagy-Related Protein-1 Homolog/genetics , Autophagy-Related Protein-1 Homolog/metabolism , Axons/metabolism , Caenorhabditis elegans/genetics , Caenorhabditis elegans Proteins/genetics , Cell Line, Tumor , Guanine Nucleotide Exchange Factors/genetics , HEK293 Cells , Humans , Neurodegenerative Diseases/genetics , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Proteomics/methods , Synapses/genetics , Synapses/metabolism , Ubiquitin-Protein Ligases/genetics
5.
ACS Med Chem Lett ; 8(12): 1258-1263, 2017 Dec 14.
Article in English | MEDLINE | ID: mdl-29259744

ABSTRACT

We present the outcome of an in silico high throughput screen (HTS) and optimization of a small molecule Unc-51-Like Kinase 1 (ULK1) inhibitor hit, SR-17398, with an indazole core. Docking studies guided design efforts that led to inhibitors with increased activity vs ULK1 (IC50 < 50 nM). The most advanced molecules in this inhibitor series (3a and 3g) hold promise for further development into selective ULK1 molecular probes to interrogate the biology of ULK1 and to assess whether selectively targeting autophagy is an effective anticancer strategy.

6.
Mol Pharmacol ; 88(6): 962-9, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26452771

ABSTRACT

Glioblastoma multiforme (GBM) is the most aggressive and common form of adult brain cancer. Current therapeutic strategies include surgical resection, followed by radiotherapy and chemotherapy. Despite such aggressive multimodal therapy, prognosis remains poor, with a median patient survival of 14 months. A proper understanding of the molecular drivers responsible for GBM progression are therefore necessary to instruct the development of novel targeted agents and enable the design of effective treatment strategies. Activation of the c-Jun N-terminal kinase isoform 2 (JNK2) is reported in primary brain cancers, where it associates with the histologic grade and amplification of the epidermal growth factor receptor (EGFR). In this manuscript, we demonstrate an important role for JNK2 in the tumor promoting an invasive capacity of EGFR variant III, a constitutively active mutant form of the receptor commonly found in GBM. Expression of EGFR variant III induces transactivation of JNK2 in GBM cells, which is required for a tumorigenic phenotype in vivo. Furthermore, JNK2 expression and activity is required to promote increased cellular invasion through stimulation of a hepatocyte growth factor-c-Met signaling circuit, whereby secretion of this extracellular ligand activates the receptor tyrosine kinase in both a cell autonomous and nonautonomous manner. Collectively, these findings demonstrate the cooperative and parallel activation of multiple RTKs in GBM and suggest that the development of selective JNK2 inhibitors could be therapeutically beneficial either as single agents or in combination with inhibitors of EGFR and/or c-Met.


Subject(s)
ErbB Receptors/biosynthesis , Glioblastoma/metabolism , Hepatocyte Growth Factor/biosynthesis , Mitogen-Activated Protein Kinase 9/biosynthesis , Receptor Protein-Tyrosine Kinases/biosynthesis , Signal Transduction/physiology , Animals , Cell Line, Tumor , Glioblastoma/pathology , Humans , Intercellular Junctions/metabolism , Male , Mice , Mice, Nude , Neoplasm Invasiveness/pathology , Xenograft Model Antitumor Assays/methods
9.
Aging Cell ; 12(5): 923-31, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23773483

ABSTRACT

The regulation of gene expression by microRNAs (miRNAs) is critical for normal development and physiology. Conversely, miRNA function is frequently impaired in cancer, and other pathologies, either by aberrant expression of individual miRNAs or dysregulation of miRNA synthesis. Here, we have investigated the impact of global disruption of miRNA biogenesis in primary fibroblasts of human or murine origin, through the knockdown of DGCR8, an essential mediator of the synthesis of canonical miRNAs. We find that the inactivation of DGCR8 in these cells results in a dramatic antiproliferative response, with the acquisition of a senescent phenotype. Senescence triggered by DGCR8 loss is accompanied by the upregulation of the cell-cycle inhibitor p21CIP1. We further show that a subset of senescence-associated miRNAs with the potential to target p21CIP1 is downregulated during DGCR8-mediated senescence. Interestingly, the antiproliferative response to miRNA biogenesis disruption is retained in human tumor cells, irrespective of p53 status. In summary, our results show that defective synthesis of canonical microRNAs results in cell-cycle arrest and cellular senescence in primary fibroblasts mediated by specific miRNAs, and thus identify global miRNA disruption as a novel senescence trigger.


Subject(s)
Fibroblasts/metabolism , MicroRNAs/biosynthesis , MicroRNAs/genetics , Proteins/metabolism , Cell Growth Processes/physiology , Cellular Senescence/physiology , Cyclin-Dependent Kinase Inhibitor p21/deficiency , Cyclin-Dependent Kinase Inhibitor p21/genetics , Fibroblasts/cytology , Gene Knockout Techniques , HEK293 Cells , Humans , RNA-Binding Proteins , Tumor Suppressor Protein p53/deficiency , Tumor Suppressor Protein p53/genetics , Up-Regulation
10.
Cancer Res ; 73(5): 1559-69, 2013 Mar 01.
Article in English | MEDLINE | ID: mdl-23243024

ABSTRACT

Glioblastoma is the most common form of primary adult brain tumors. A majority of glioblastomas grow invasively into distant brain tissue, leading to tumor recurrence, which is ultimately incurable. It is, therefore, essential to discover master regulators that control glioblastoma invasiveness and target them therapeutically. We show here that the transcriptional regulator Id-1 plays a critical role in modulating the invasiveness of glioblastoma cell lines and primary glioblastoma cells. Id-1 expression levels positively correlate with glioma cell invasiveness in culture and with histopathologic grades in patient biopsies. Id-1 knockdown dramatically reduces glioblastoma cell invasion that is accompanied by profound morphologic changes and robust reduction in expression levels of "mesenchymal" markers, as well as inhibition of self-renewal potential and downregulation of glioma stem cell markers. Importantly, genetic knockdown of Id-1 leads to a significant increase in survival in an orthotopic model of human glioblastoma. Furthermore, we show that a nontoxic compound, cannabidiol, significantly downregulates Id-1 gene expression and associated glioma cell invasiveness and self-renewal. In addition, cannabidiol significantly inhibits the invasion of glioblastoma cells through an organotypic brain slice and glioma progression in vivo. Our results suggest that Id-1 regulates multiple tumor-promoting pathways in glioblastoma and that drugs targeting Id-1 represent a novel and promising strategy for improving the therapy and outcome of patients with glioblastoma.


Subject(s)
Brain Neoplasms/metabolism , Glioblastoma/metabolism , Inhibitor of Differentiation Protein 1/physiology , Neoplasm Invasiveness/genetics , Animals , Brain Neoplasms/pathology , Cannabidiol/pharmacology , Cell Line, Tumor , Female , Glioblastoma/pathology , Humans , Inhibitor of Differentiation Protein 1/antagonists & inhibitors , Inhibitor of Differentiation Protein 1/metabolism , Mice , Mice, Nude , Neurospora , RNA Interference , Transplantation, Heterologous , Up-Regulation
11.
Bol. soc. Rorschach São Paulo ; 8(1): 42-49, jan./dez. 1991-jan./dez. 1995.
Article | Index Psychology - journals | ID: psi-722

Subject(s)
Syndrome , Panic , Congress , Syndrome , Panic , Congress
14.
Arq. bras. psicol. (Rio J. 1979) ; 40(2): 36-9, abr.-jun. 1988.
Article in Portuguese | LILACS | ID: lil-82716

ABSTRACT

A autora defende o mesmo ponta de vista por ela levantado em estudos e pesquisas anteriores, relativo a necessidade de os psicólogos realizarem pesquisas com indivíduos de seus respectivos países para ter dados normativos a seu respeito. Nega a universidade desses dados, embora aceite que existem aspectos ontológicos, transcendentais e essenciais que säo comuns a generalidae dos homens. Ilustra sua opiniäo com dados referentes a suas pesquisas com criança, adolescentes, adultos e idosos


Subject(s)
Child , Adolescent , Adult , Middle Aged , Humans , Male , Female , Cross-Cultural Comparison , Rorschach Test
15.
Arq. bras. psicol. (Rio J. 1979) ; 40(2): 36-39, abr./jun. 1988.
Article | Index Psychology - journals | ID: psi-10377

ABSTRACT

A autora defende o mesmo ponto de vista por ela levantando em estudos e pesquisas anteriores, relativo a necessidade de os psicologos realizarem pesquisas com individuos de seus respectivos paises para ter dados normativos a seu respeito. Nega a universalidade desses dados, embora aceite que existem aspectos ontologicos, transcendentais e essenciais que sao comuns a generalidade dos homens. Ilustra sua opiniao com dados referentes a suas pesqusas com criancas, adolescentes, adultos e idosos.


Subject(s)
Projective Techniques , Rorschach Test , Projective Techniques , Rorschach Test
16.
São Paulo; Casa do Psicólogo; 1988. 180 p. tab.
Monography in Portuguese | LILACS, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1085759
17.
Arq. bras. psicol. (Rio J. 1979) ; 39(2): 57-66, abr.-jun. 1987. tab
Article in Portuguese | LILACS | ID: lil-91697

ABSTRACT

Trata-se de um estudo do perfil psicológico da terceira idade hoje. O instrumento utilizado foi o Método de Rorschach e a amostra constou de 200 indivíduos, 100 residentes em seus lares e 100 radicados em abrigos e casas de repouso. Além de posiçäo vivencial, a criatividade e os mecanismos de adaptaçäo, no processo de envelhecimento psicológico, relatam-se as diferenças encontradas entre o grupo institucionalizado e aquele que permanece em seu lar


Subject(s)
Humans , Male , Female , Adaptation, Psychological , Aging , Creativity , Middle Aged , Rorschach Test
18.
Arq. bras. psicol. (Rio J. 1979) ; 39(2): 57-66, abr./jun. 1987.
Article | Index Psychology - journals | ID: psi-7524

ABSTRACT

Trata-se de um estudo do perfil psicologico da terceira idade hoje. O instrumento utilizado foi o Metodo de Rosrchach e a amostra constou de 200 idividuos, 100 residentes em seus lares e 100 radicados em abrigos e casas de repouso. Alem de posicao vivencial, a criatividade e os mecanismos de adaptacao, no processo de envelhecimento psicologico, relatam-se as diferencas encontradas entre o grupo institucionalizado e aquele que permanece em seu lar.


Subject(s)
Projective Techniques , Aged , Rorschach Test , Aging , Projective Techniques , Aged , Rorschach Test , Aging
19.
Arq. bras. psicol. (Rio J. 1979) ; 38(2): 134-9, abr.-jun. 1986.
Article in Portuguese | LILACS | ID: lil-93092

ABSTRACT

Foi analisada a influência da cultura no desenvolvimento da personalidade através do Método de Rorschach. Revisäo crítica de algumas pesquisas a esse respeito mostram que tal fator näo é o mais importante para o equilíbrio da personalidade. Culturas diferentes säo muito mais atuantes que um nível mais ou menos elevado de cultrura. Levanta-se a hipótese de que o handicap psicológico e as carências afetivas podem ser os fatores mais destrutivos dentre todos os tipos de carência


Subject(s)
Child , Humans , Male , Female , Cultural Deprivation , Mood Disorders , Personality Development , Rorschach Test
20.
Arq. bras. psicol. (Rio J. 1979) ; 38(1): 73-9, jun.-mar. 1986.
Article in Portuguese | LILACS | ID: lil-92930

ABSTRACT

A autora fez um estudo mediante a Técnica de Rorchach de 100 indivíduos do sexo masculino na fase da vida considerada como "terceira idade". Säo analisados o tipo de vivência ou posicionamento diante da vida, as possibilidades criativas, defesas, sinais de deterioraçäo e possíveis alteraçöes de identidade


Subject(s)
Humans , Male , Aging , Middle Aged , Rorschach Test
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