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1.
Front Neurosci ; 17: 1213410, 2023.
Article in English | MEDLINE | ID: mdl-37599992

ABSTRACT

Fragile X Syndrome (FXS) is a neurodevelopmental disorder and the leading monogenic cause of autism and intellectual disability. For years, several efforts have been made to develop an effective therapeutic approach to phenotypically rescue patients from the disorder, with some even advancing to late phases of clinical trials. Unfortunately, none of these attempts have completely succeeded, bringing urgency to further expand and refocus research on FXS therapeutics. FXS arises at early stages of postnatal development due to the mutation and transcriptional silencing of the Fragile X Messenger Ribonucleoprotein 1 gene (FMR1) and consequent loss of the Fragile X Messenger Ribonucleoprotein (FMRP) expression. Importantly, FMRP expression is critical for the normal adult nervous system function, particularly during specific windows of embryogenic and early postnatal development. Cellular proliferation, migration, morphology, axonal guidance, synapse formation, and in general, neuronal network establishment and maturation are abnormally regulated in FXS, underlying the cognitive and behavioral phenotypes of the disorder. In this review, we highlight the relevance of therapeutically intervening during critical time points of development, such as early postnatal periods in infants and young children and discuss past and current clinical trials in FXS and their potential to specifically target those periods. We also discuss potential benefits, limitations, and disadvantages of these pharmacological tools based on preclinical and clinical research.

2.
Front Public Health ; 11: 1191377, 2023.
Article in English | MEDLINE | ID: mdl-37492136

ABSTRACT

Introduction: As the SARS-CoV-2 continues to evolve, new variants pose a significant threat by potentially overriding the immunity conferred by vaccination and natural infection. This scenario can lead to an upswing in reinfections, amplified baseline epidemic activity, and localized outbreaks. In various global regions, estimates of breakthrough cases associated with the currently circulating viral variants, such as Omicron, have been reported. Nonetheless, specific data on the reinfection rate in Chile still needs to be included. Methods: Our study has focused on estimating COVID-19 reinfections per wave based on a sample of 578,670 RT-qPCR tests conducted at the University of Santiago of Chile (USACH) from April 2020 to July 2022, encompassing 345,997 individuals. Results: The analysis reveals that the highest rate of reinfections transpired during the fourth and fifth COVID-19 waves, primarily driven by the Omicron variant. These findings hold despite 80% of the Chilean population receiving complete vaccination under the primary scheme and 60% receiving at least one booster dose. On average, the interval between initial infection and reinfection was found to be 372 days. Interestingly, reinfection incidence was higher in women aged between 30 and 55. Additionally, the viral load during the second infection episode was lower, likely attributed to Chile's high vaccination rate. Discussion: This study demonstrates that the Omicron variant is behind Chile's highest number of reinfection cases, underscoring its potential for immune evasion. This vital epidemiological information contributes to developing and implementing effective public health policies.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Female , Adult , Middle Aged , SARS-CoV-2/genetics , COVID-19/diagnosis , COVID-19/epidemiology , Chile/epidemiology , Reinfection/epidemiology
3.
iScience ; 24(12): 103520, 2021 Dec 17.
Article in English | MEDLINE | ID: mdl-34950860

ABSTRACT

T cell activation requires the processing and presentation of antigenic peptides in the context of a major histocompatibility complex (MHC complex). Cross-dressing is a non-conventional antigen presentation mechanism, involving the transfer of preformed peptide/MHC complexes from whole cells, such as apoptotic cells (ACs) to the cell membrane of professional antigen-presenting cells (APCs), such as dendritic cells (DCs). This is an essential mechanism for the induction of immune response against viral antigens, tumors, and graft rejection, which until now has not been clarified. Here we show for first time that the P2X7 receptor (P2X7R) is crucial to induce cross-dressing between ACs and Bone-Marrow DCs (BMDCs). In controlled ex vivo assays, we found that the P2X7R in both ACs and BMDCs is required to induce membrane and fully functional peptide/MHC complex transfer to BMDCs. These findings show that acquisition of ACs-derived preformed antigen/MHC-I complexes by BMDCs requires P2X7R expression.

4.
Molecules ; 26(20)2021 Oct 12.
Article in English | MEDLINE | ID: mdl-34684731

ABSTRACT

Type 2 diabetes and obesity are major problems worldwide and dietary polyphenols have shown efficacy to ameliorate signs of these diseases. Anthocyanins from berries display potent antioxidants and protect against weight gain and insulin resistance in different models of diet-induced metabolic syndrome. Olanzapine is known to induce an accelerated form of metabolic syndrome. Due to the aforementioned, we evaluated whether delphinidin-3,5-O-diglucoside (DG) and delphinidin-3-O-sambubioside-5-O-glucoside (DS), two potent antidiabetic anthocyanins isolated from Aristotelia chilensis fruit, could prevent olanzapine-induced steatosis and insulin resistance in liver and skeletal muscle cells, respectively. HepG2 liver cells and L6 skeletal muscle cells were co-incubated with DG 50 µg/mL or DS 50 µg/mL plus olanzapine 50 µg/mL. Lipid accumulation was determined in HepG2 cells while the expression of p-Akt as a key regulator of the insulin-activated signaling pathways, mitochondrial function, and glucose uptake was assessed in L6 cells. DS and DG prevented olanzapine-induced lipid accumulation in liver cells. However, insulin signaling impairment induced by olanzapine in L6 cells was not rescued by DS and DG. Thus, anthocyanins modulate lipid metabolism, which is a relevant factor in hepatic tissue, but do not significantly influence skeletal muscle, where a potent antioxidant effect of olanzapine was found.


Subject(s)
Anthocyanins/pharmacology , Elaeocarpaceae/metabolism , Glucosides/pharmacology , Anthocyanins/chemistry , Anthocyanins/metabolism , Diabetes Mellitus, Type 2/metabolism , Fatty Liver/metabolism , Glucosides/chemistry , Hep G2 Cells , Hepatocytes/metabolism , Humans , Hypoglycemic Agents/pharmacology , Insulin/metabolism , Insulin Resistance/physiology , Lipid Metabolism , Lipids/pharmacology , Liver/drug effects , Liver/pathology , Muscle Fibers, Skeletal/metabolism , Muscle, Skeletal/metabolism , Obesity/metabolism , Olanzapine , Plant Extracts/pharmacology , Polyphenols/pharmacology
5.
Biomed Res Int ; 2021: 6626851, 2021.
Article in English | MEDLINE | ID: mdl-33623783

ABSTRACT

Active immunotherapy against cancer is based on immune system stimulation, triggering efficient and long-lasting antigen-specific immune responses. Immunization strategies using whole dead cells from tumor tissue, containing specific antigens inside, have become a promising approach, providing efficient lymphocyte activation through dendritic cells (DCs). In this work, we generate whole dead tumor cells from CT26, E.G7, and EL4 live tumor cells as antigen sources, which termed immunogenic cell bodies (ICBs), generated by a simple and cost-efficient starvation-protocol, in order to determine whether are capable of inducing a transversal anticancer response regardless of the tumor type, in a similar way to what we describe previously with B16 melanoma. We evaluated the anticancer effects of immunization with doses of ICBs in syngeneic murine tumor models. Our results showed that mice's immunization with ICBs-E.G7 and ICBs-CT26 generate 18% and 25% of tumor-free animals, respectively. On the other hand, all carrying tumor-animals and immunized with ICBs, including ICBs-EL4, showed a significant delay in their growth compared to not immunized animals. These effects relate to DCs maturation, cytokine production, increase in CD4+T-bet+ and CD4+ROR-γt+ population, and decrease of T regulatory lymphocytes in the spleen. Altogether, our data suggest that whole dead tumor cell-based cancer immunotherapy generated by a simple starvation protocol is a promising way to develop complementary, innovative, and affordable antitumor therapies in a broad spectrum of tumors.


Subject(s)
Antigens, Neoplasm , Colonic Neoplasms/immunology , Immunotherapy , Lymphoma/immunology , Tumor Cells, Cultured/immunology , Animals , Antigens, Neoplasm/immunology , Antigens, Neoplasm/metabolism , Autophagy , Cell Culture Techniques , Cytokines/metabolism , Female , Male , Mice , Mice, Inbred C57BL , Spleen/cytology
6.
Immunotherapy ; 13(4): 309-326, 2021 03.
Article in English | MEDLINE | ID: mdl-33397152

ABSTRACT

Aim: Whole dead tumor cells can be used as antigen source and the induction of protective immune response could be enhanced by damage-associated molecular patterns. Materials & methods: We generated whole dead tumor cells called B16-immunogenic cell bodies (ICBs) from B16 melanoma cells by nutrient starvation and evaluated the in vivo antitumor effect of B16-ICBs plus ATP and polymyxin B (PMB). Results: The subcutaneous immunization with B16-ICBs + PMB + ATP a 50% of tumor-free animals and induced a significant delay in tumor growth in a prophylactic approach. These results correlated with maturation of bone marrow-derived dendritic cells and activation of T CD8+ lymphocytes in vitro. Conclusion: Altogether, ICB + ATP + PMB is efficient in inducing the antitumor efficacy of the whole dead tumor cells vaccine.


Subject(s)
Adenosine Triphosphate/immunology , Cancer Vaccines/immunology , Melanoma, Experimental/immunology , Polymyxin B/immunology , Adenosine Triphosphate/administration & dosage , Alarmins/administration & dosage , Alarmins/immunology , Animals , Antigen Presentation , Antigens, Neoplasm/immunology , CD40 Antigens/metabolism , Cancer Vaccines/administration & dosage , Cytokines/metabolism , Dendritic Cells/immunology , Dendritic Cells/metabolism , Immunization , Melanoma, Experimental/pathology , Melanoma, Experimental/prevention & control , Mice , Mice, Inbred C57BL , Phagocytosis , Polymyxin B/administration & dosage , Spleen/immunology , Tumor Cells, Cultured
7.
Biomed Res Int ; 2020: 4045760, 2020.
Article in English | MEDLINE | ID: mdl-32626742

ABSTRACT

Reovirus is known to have an anticancer effect in both the preclinical and clinical assays. Current evidence suggests that the reovirus-mediated impact on tumor growth depends on the activation of specific antitumor immune responses. A feasible explanation for the oncolytic effects and immune system activation is through the expression of the fusogenic reovirus protein. In this work, we evaluated the in vivo antitumor effects of the expression of fusogenic protein p10 of avian reovirus (ARV-p10). We used chitosan nanoparticles (CH-NPs) as a vehicle for the ARV-p10 DNA in murine B16 melanoma models both in vitro and in vivo. We confirmed that ARV-p10 delivery through a chitosan-based formulation (ARV-p10 CH-NPs) was capable of inducing cell fusion in cultured melanoma cells, showing a mild cytotoxic effect. Interestingly, intratumor injection of ARV-p10 CH-NPs delayed tumor growth, without changing lymphoid populations in the tumor tissue and spleen. The injection of chitosan nanoparticles (CH-NPs) also delayed tumor growth, suggesting the nanoparticle itself would attack tumor cells. In conclusion, we proved that in vitro ARV-p10 protein expression using CH-NPs in murine melanoma cells induces a cytotoxic effect associated with its cell fusion. Further studies are necessary for establishing a protocol for efficient in vivo DNA delivery of fusion proteins to produce an antitumoral effect.


Subject(s)
Cancer Vaccines , Melanoma, Experimental , Orthoreovirus, Avian , Recombinant Fusion Proteins , Viral Proteins , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cancer Vaccines/chemistry , Cancer Vaccines/genetics , Cancer Vaccines/pharmacology , Cell Survival/drug effects , Chitosan/chemistry , Drug Delivery Systems/methods , Mice , Mice, Inbred C57BL , Nanoparticles/chemistry , Orthoreovirus, Avian/genetics , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/pharmacology , Transfection , Viral Proteins/chemistry , Viral Proteins/genetics
8.
Mediators Inflamm ; 2020: 8680692, 2020.
Article in English | MEDLINE | ID: mdl-32410869

ABSTRACT

Oncolytic virus therapy has been tested against cancer in preclinical models and clinical assays. Current evidence shows that viruses induce cytopathic effects associated with fusogenic protein-mediated syncytium formation and immunogenic cell death of eukaryotic cells. We have previously demonstrated that tumor cell bodies generated from cells expressing the fusogenic protein of the infectious salmon anemia virus (ISAV-F) enhance crosspriming and display prophylactic antitumor activity against melanoma tumors. In this work, we evaluated the effects of the expression of ISAV-F on the B16 melanoma model, both in vitro and in vivo, using chitosan nanoparticles as transfection vehicle. We confirmed that the transfection of B16 tumor cells with chitosan nanoparticles (NP-ISAV) allows the expression of a fusogenically active ISAV-F protein and decreases cell viability because of syncytium formation in vitro. However, the in vivo transfection induces a delay in tumor growth, without inducing changes on the lymphoid populations in the tumor and the spleen. Altogether, our observations show that expression of ISAV fusion protein using chitosan nanoparticles induces cell fusion in melanoma cells and slight antitumor response.


Subject(s)
Antineoplastic Agents/pharmacology , Chitosan/chemistry , Melanoma/drug therapy , Nanoparticles/chemistry , Oncolytic Virotherapy/methods , Skin Neoplasms/drug therapy , Animals , Cell Line, Tumor , Cell Survival , Chitosan/metabolism , DNA, Complementary/metabolism , Giant Cells/metabolism , Humans , Isavirus/genetics , Lymphocytes/cytology , Melanoma, Experimental , Mice , Mice, Inbred C57BL , Mice, Transgenic , Nanomedicine/methods , Orthomyxoviridae Infections/genetics , Recombinant Fusion Proteins/chemistry , Surface Properties , Transfection
9.
Behav Brain Res ; 363: 182-190, 2019 05 02.
Article in English | MEDLINE | ID: mdl-30721762

ABSTRACT

Moderate reduction of dietary protein (from 25% to 8% casein) in pregnant rats, calorically compensated by carbohydrates, gives rise to 'hidden prenatal malnutrition' (HPM) in the offspring since it does not alter body and brain weights of pups at birth. However, this dietary treatment leads to decreased ß-adrenoceptor signaling and brain derived neurotrophic factor (BDNF) levels in the pup' brain, altogether with defective cortical long-term potentiation (LTP) and lowered visuospatial memory performance. Since early postnatal environmental enrichment (EE) has been shown to exert plastic effects on the developing brain and neuroprotection both on cognition and on structural properties of the neocortex, in the present study we addressed the question of whether early postnatal EE during the lactation period could exert compensatory changes in the expression of ®-adrenergic receptors and BDNF in the neocortex of HPM rats, and if these effects are associated with an improvement or even a restore of both neocortical LTP in vivo and cognitive performance induced by HPM. The results obtained show that EE restored ß-adrenoceptor density, BDNF expression and the ability to support LTP at prefrontal and occipital cortices of HPM rats. Besides, EE improved learning performance in visuospatial and operant conditioning tasks. The latter support the notion that adequate maternal protein nutrition during pregnancy is required for proper brain development and function. Further, the results highlight the role of environmental enrichment during early postnatal life in increasing later brain plasticity and exerting neuroprotection against brain deficits induced by prenatal malnutrition.


Subject(s)
Cerebral Cortex/physiology , Learning/physiology , Postnatal Care/methods , Animals , Animals, Newborn/psychology , Brain-Derived Neurotrophic Factor/metabolism , Cognition/physiology , Female , Long-Term Potentiation/physiology , Male , Malnutrition/physiopathology , Memory/physiology , Neocortex/physiopathology , Neuronal Plasticity/physiology , Occipital Lobe/physiopathology , Pregnancy , Prenatal Exposure Delayed Effects/physiopathology , Rats , Rats, Sprague-Dawley , Receptors, Adrenergic, beta/metabolism
10.
Oncotarget ; 8(6): 9767-9782, 2017 Feb 07.
Article in English | MEDLINE | ID: mdl-28038459

ABSTRACT

Neogenin-1 (NEO1) is a transmembrane receptor involved in axonal guidance, angiogenesis, neuronal cell migration and cell death, during both embryonic development and adult homeostasis. It has been described as a dependence receptor, because it promotes cell death in the absence of its ligands (Netrin and Repulsive Guidance Molecule (RGM) families) and cell survival when they are present. Although NEO1 and its ligands are involved in tumor progression, their precise role in tumor cell survival and migration remain unclear. Public databases contain extensive information regarding the expression of NEO1 and its ligands Netrin-1 (NTN1) and Netrin-4 (NTN4) in primary neuroblastoma (NB) tumors. Analysis of this data revealed that patients with high expression levels of both NEO1 and NTN4 have a poor survival rate. Accordingly, our analyses in NB cell lines with different genetic backgrounds revealed that knocking-down NEO1 reduces cell migration, whereas silencing of endogenous NTN4 induced cell death. Conversely, overexpression of NEO1 resulted in higher cell migration in the presence of NTN4, and increased apoptosis in the absence of ligand. Increased apoptosis was prevented when utilizing physiological concentrations of exogenous Netrin-4. Likewise, cell death induced after NTN4 knock-down was rescued when NEO1 was transiently silenced, thus revealing an important role for NEO1 in NB cell survival. In vivo analysis, using the chicken embryo chorioallantoic membrane (CAM) model, showed that NEO1 and endogenous NTN4 are involved in tumor extravasation and metastasis. Our data collectively demonstrate that endogenous NTN4/NEO1 maintain NB growth via both pro-survival and pro-migratory molecular signaling.


Subject(s)
Cell Movement , Chorioallantoic Membrane/blood supply , Nerve Tissue Proteins/metabolism , Netrins/metabolism , Neuroblastoma/metabolism , Receptors, Cell Surface/metabolism , Animals , Apoptosis , Cell Line, Tumor , Cell Survival , Chick Embryo , Gene Expression Regulation, Neoplastic , Humans , Kaplan-Meier Estimate , Neoplasm Invasiveness , Nerve Tissue Proteins/genetics , Netrins/genetics , Neuroblastoma/genetics , Neuroblastoma/mortality , Neuroblastoma/secondary , RNA Interference , Receptors, Cell Surface/genetics , Signal Transduction , Time Factors , Transfection
11.
Genetics ; 197(1): 175-92, 2014 May.
Article in English | MEDLINE | ID: mdl-24558258

ABSTRACT

Insulin-producing cells (IPCs) in the Drosophila brain produce and release insulin-like peptides (ILPs) to the hemolymph. ILPs are crucial for growth and regulation of metabolic activity in flies, functions analogous to those of mammalian insulin and insulin-like growth factors (IGFs). To identify components functioning in IPCs to control ILP production, we employed genomic and candidate gene approaches. We used laser microdissection and messenger RNA sequencing to characterize the transcriptome of larval IPCs. IPCs highly express many genes homologous to genes active in insulin-producing ß-cells of the mammalian pancreas. The genes in common encode ILPs and proteins that control insulin metabolism, storage, secretion, ß-cell proliferation, and some not previously linked to insulin production or ß-cell function. Among these novelties is unc-104, a kinesin 3 family gene, which is more highly expressed in IPCs compared to most other neurons. Knockdown of unc-104 in IPCs impaired ILP secretion and reduced peripheral insulin signaling. Unc-104 appears to transport ILPs along axons. As a complementary approach, we tested dominant-negative Rab genes to find Rab proteins required in IPCs for ILP production or secretion. Rab1 was identified as crucial for ILP trafficking in IPCs. Inhibition of Rab1 in IPCs increased circulating sugar levels, delayed development, and lowered weight and body size. Immunofluorescence labeling of Rab1 showed its tight association with ILP2 in the Golgi of IPCs. Unc-104 and Rab1 join other proteins required for ILP transport in IPCs.


Subject(s)
Drosophila melanogaster/cytology , Drosophila melanogaster/genetics , Gene Expression Profiling , Insulin-Secreting Cells/metabolism , Insulin/metabolism , Animals , Axons/metabolism , Carbohydrate Metabolism , Conserved Sequence , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Drosophila melanogaster/growth & development , Drosophila melanogaster/metabolism , Hemolymph/metabolism , Insulin Secretion , Insulin-Secreting Cells/cytology , Larva/cytology , Larva/genetics , Larva/growth & development , Larva/metabolism , Male , RNA, Messenger/genetics , RNA, Messenger/metabolism
12.
Int J Cancer ; 134(1): 21-31, 2014 Jan 01.
Article in English | MEDLINE | ID: mdl-23775842

ABSTRACT

The canonical Sonic Hedgehog (Shh)/Gli pathway plays multiples roles during central nervous system (CNS) development. To elucidate the molecular repertoire of Shh mediators, we have recently described novel transcriptional targets in response to Shh pathway modulation. Among them, we were able to identify Neogenin1 (Neo1), a death dependence receptor, as a new direct Shh downstream regulator in neural precursor proliferation. As appropriate Shh signaling is required for cerebellar growth and alterations cause Shh-driven medulloblastoma (MB), here we have addressed the role of the Shh/Neogenin1 interaction in the context of cerebellar development and cancer. We demonstrate that the Shh pathway regulates Neogenin1 expression in mouse models that recapitulate the Shh MB subtype. We show that the canonical Shh pathway directly regulates the Neo1 gene acting through an upstream sequence in its promoter both in vitro and in vivo in granule neuron precursor cells. We also identified and characterized a functional Gli-binding site in the first intron of the human NEO1 gene. Gene expression profiling of more than 300 MB shows that NEO1 is indeed upregulated in SHH tumors compared to the other MB subgroups. Finally, we provide evidence that NEO1 is necessary for cell cycle progression in a human MB cell line, because a loss of function of NEO1 arrests cells in the G2/M phase. Taken together, these results highlight Neogenin1 as a novel downstream effector of the Shh pathway in MB and a possible therapeutic target.


Subject(s)
Cerebellar Neoplasms/metabolism , Hedgehog Proteins/metabolism , Medulloblastoma/metabolism , Membrane Proteins/metabolism , Signal Transduction/physiology , Animals , Blotting, Western , Cell Cycle/physiology , Cell Line, Tumor , Cerebellar Neoplasms/pathology , Disease Models, Animal , Gene Expression Regulation, Neoplastic/physiology , Humans , Medulloblastoma/pathology , Mice , Transcriptome
13.
BMC Genomics ; 13: 2, 2012 Jan 03.
Article in English | MEDLINE | ID: mdl-22214306

ABSTRACT

BACKGROUND: The increasing number of developmental events and molecular mechanisms associated with the Hedgehog (Hh) pathway from Drosophila to vertebrates, suggest that gene regulation is crucial for diverse cellular responses, including target genes not yet described. Although several high-throughput, genome-wide approaches have yielded information at the genomic, transcriptional and proteomic levels, the specificity of Gli binding sites related to direct target gene activation still remain elusive. This study aims to identify novel putative targets of Gli transcription factors through a protein-DNA binding assay using yeast, and validating a subset of targets both in-vitro and in-vivo. Testing in different Hh/Gli gain- and loss-of-function scenarios we here identified known (e.g., ptc1) and novel Hh-regulated genes in zebrafish embryos. RESULTS: The combined yeast-based screening and MEME/MAST analysis were able to predict Gli transcription factor binding sites, and position mapping of these sequences upstream or in the first intron of promoters served to identify new putative target genes of Gli regulation. These candidates were validated by qPCR in combination with either the pharmacological Hh/Gli antagonist cyc or the agonist pur in Hh-responsive C3H10T1/2 cells. We also used small-hairpin RNAs against Gli proteins to evaluate targets and confirm specific Gli regulation their expression. Taking advantage of mutants that have been identified affecting different components of the Hh/Gli signaling system in the zebrafish model, we further analyzed specific novel candidates. Studying Hh function with pharmacological inhibition or activation complemented these genetic loss-of-function approaches. We provide evidence that in zebrafish embryos, Hh signaling regulates sfrp2, neo1, and c-myc expression in-vivo. CONCLUSION: A recently described yeast-based screening allowed us to identify new Hh/Gli target genes, functionally important in different contexts of vertebrate embryonic development.


Subject(s)
Genetic Techniques , Hedgehog Proteins/metabolism , Oncogene Proteins/metabolism , Saccharomyces cerevisiae , Trans-Activators/metabolism , Animals , Cell Line , Embryo, Nonmammalian/drug effects , Embryo, Nonmammalian/metabolism , Embryonic Development , Gene Expression Regulation, Developmental , Genetic Techniques/standards , Hedgehog Proteins/agonists , Membrane Proteins/metabolism , Mice , Oncogene Proteins/antagonists & inhibitors , Oncogene Proteins/genetics , Promoter Regions, Genetic , Proto-Oncogene Proteins c-myc/metabolism , RNA Interference , RNA, Small Interfering/metabolism , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism , Signal Transduction , Trans-Activators/antagonists & inhibitors , Trans-Activators/genetics , Veratrum Alkaloids/pharmacology , Zebrafish/growth & development , Zebrafish Proteins/metabolism , Zinc Finger Protein GLI1
14.
Biol Res ; 45(3): 223-30, 2012.
Article in English | MEDLINE | ID: mdl-23283432

ABSTRACT

The Sonic Hegdehog/GLI (SHH/GLI) pathway has been extensively studied for its role in developmental and cancer biology. During early embryonic development the SHH pathway is involved mainly in pattern formation, while in latter stages its function in stem cell and progenitor proliferation becomes increasingly relevant. During postnatal development and in adult tissues, SHH/GLI promotes cell homeostasis by actively regulating gene transcription, recapitulating the function observed during normal tissue growth. In this review, we will briefly discuss the fundamental importance of SHH/GLI in tumor growth and cancer evolution and we will then provide insights into a possible novel mechanism of SHH action in cancer through autophagy modulation in cancer stem cells. Autophagy is a homeostatic mechanism that when disrupted can promote and accelerate tumor progression in both cancer cells and the stroma that harbors tumorigenesis. Understanding possible new targets for SHH signaling and its contribution to cancer through modulation of autophagy might provide better strategies in order to design combined treatments and perform clinical trials.


Subject(s)
Autophagy/physiology , Hedgehog Proteins/physiology , Neoplastic Stem Cells/pathology , Neuroblastoma/physiopathology , Transcription Factors/physiology , Cell Line, Tumor , Cell Proliferation , Humans , Neuroblastoma/pathology , Neuroblastoma/therapy , Signal Transduction , Zinc Finger Protein GLI1
15.
Biol. Res ; 45(3): 223-230, 2012. ilus, tab
Article in English | LILACS | ID: lil-659280

ABSTRACT

The Sonic Hegdehog/GLI (SHH/GLI) pathway has been extensively studied for its role in developmental and cancer biology. During early embryonic development the SHH pathway is involved mainly in pattern formation, while in latter stages its function in stem cell and progenitor proliferation becomes increasingly relevant. During postnatal development and in adult tissues, SHH/GLI promotes cell homeostasis by actively regulating gene transcription, recapitulating the function observed during normal tissue growth. In this review, we will briefly discuss the fundamental importance of SHH/GLI in tumor growth and cancer evolution and we will then provide insights into a possible novel mechanism of SHH action in cancer through autophagy modulation in cancer stem cells. Autophagy is a homeostatic mechanism that when disrupted can promote and accelerate tumor progression in both cancer cells and the stroma that harbors tumorigenesis. Understanding possible new targets for SHH signaling and its contribution to cancer through modulation of autophagy might provide better strategies in order to design combined treatments and perform clinical trials.


Subject(s)
Humans , Autophagy/physiology , Hedgehog Proteins/physiology , Neoplastic Stem Cells/pathology , Neuroblastoma/physiopathology , Transcription Factors/physiology , Cell Line, Tumor , Cell Proliferation , Neuroblastoma/pathology , Neuroblastoma/therapy , Signal Transduction
16.
Eur J Neurosci ; 33(4): 589-98, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21219478

ABSTRACT

Despite considerable progress, the mechanisms that control neural progenitor differentiation and behavior, as well as their functional integration into adult neural circuitry, are far from being understood. Given the complexity of the mammalian brain, non-mammalian models provide an excellent model to study neurogenesis, including both the cellular composition of the neurogenic microenvironment, and the factors required for precursor growth and maintenance. In particular, we chose to address the question of the control of progenitor proliferation by Sonic hedgehog (Shh) using the zebrafish dorsal mesencephalon, known as the optic tectum (OT), as a model system. Here we show that either inhibiting pharmacologically or eliminating hedgehog (Hh) signaling by using mutants that lack essential components of the Hh pathway reduces neural progenitor cell proliferation affecting neurogenesis in the OT. On the contrary, pharmacological gain-of-function experiments result in significant increase in proliferation. Importantly, Shh-dependent function controls neural progenitor cell behavior as sox2-positive cell populations were lost in the OT in the absence of Hh signaling, as evidenced in slow-muscle-omitted (smu) mutants and with timed cyclopamine inhibition. Expressions of essential components of the Hh pathway reveal for the first time a late dorsal expression in the embryonic OT. Our observations argue strongly for a role of Shh in neural progenitor biology in the OT and provide comparative data to our current understanding of progenitor/stem cell mechanisms that place Shh as a key niche factor in the dorsal brain.


Subject(s)
Cell Division/physiology , Hedgehog Proteins/metabolism , Neural Stem Cells/physiology , Signal Transduction/physiology , Tectum Mesencephali , Zebrafish Proteins/metabolism , Zebrafish , Animals , Cell Proliferation , Hedgehog Proteins/genetics , Neural Stem Cells/cytology , Neurogenesis/physiology , Tectum Mesencephali/cytology , Tectum Mesencephali/embryology , Tectum Mesencephali/growth & development , Zebrafish/anatomy & histology , Zebrafish/embryology , Zebrafish/growth & development , Zebrafish Proteins/genetics
17.
Acta cancerol ; 37(1): 24-27, 2009. graf, tab
Article in Spanish | LILACS, LIPECS | ID: lil-673606

ABSTRACT

Los países que han disminuido la morbimortalidad por cáncer de cuello uterino en aproximadamente un 60%, desarrollaron programas de prevención a través del tamizaje periódico y frecuente logrando coberturas altas en la población de riesgo brindando tratamiento inmediato y posterior seguimiento de las lesiones precancerosas. En el Perú los esfuerzos para combatir el cáncer de cuello uterino se enfoco en tomar muestras de papanicolou en la población de riesgo sin seguimiento posterior de las pacientes con citología positiva. En Junín departamento de la sierra central el 28 de Noviembre del 2006, se crea la primera Unidad de tratamiento de displasia de cuello uterino en el País, con claros objetivos; evaluación, diagnostico y tratamiento de lesiones precancerosas de cuello uterino de la población femenina de la región Junín. Después de 30 meses de funcionamiento se han logrado las siguientes actos médicos: 3064 consultas especializadas , 1135 paps, 363 colposcopias, 81 Conos Leep,98 criotrapia y 109 referencias al INEN(carcinomas de cuello uterino infiltrante). Esta experiencia de la unidad de displasia de cuello uterino, realiza en Concepción, Junín se podrá implementar en las distintas regiones a lo largo de todo nuestro país dando así un paso importante para cerrar el circulo de un programa exitoso en la lucha contra el cáncer de cuello Uterino en el Perú.


The countries who have reduced morbidity and mortality of cervical cancer by about 60%, implemented prevention programs and developed through regular and frequent screening in female patients achieving high coverage in the population at risk by providing immediate treatment and subsequent monitoring of precancerous lesions. In Peru's efforts to combat cervical cancer are focused by taking samples of cervical citology in the risk population without subsequent monitoring of patients with positive cytology. Junin department of the central highlands, two years ago ( November, 28, 2006) establishing the first treatment unit of cervical dysplasia in our Country, with clear objectives, evaluation, diagnosis and treatment of cervical precancerous lesions in female population the Concepcion - Junin and around cities. After 30 months of activity at the Unit of cervical dysplasia have been made following medical events: 3064 specialized consultations, 1135 samples of cervical citology, 363 colposcopy, 81 Cono Leep, 98 criotherapy and 109 references to INEN (invasive cervical Carcinoma). This experience of the Unit of cervical dysplasia, held in Concepcion, Junin could be implemented in different regions throughout our country, giving thus an important step to close the loop of a successful program to combat cancer cervix in Peru.


Subject(s)
Humans , Female , Uterine Cervical Dysplasia/diagnosis , Uterine Cervical Dysplasia/therapy , Vaginal Smears , Uterine Cervical Neoplasms/prevention & control
18.
Acta cancerol ; 37(1): 28-29, 2009.
Article in Spanish | LILACS, LIPECS | ID: lil-673607

ABSTRACT

En la actualidad se considera que la infección con el papiloma virus humano es una de las enfermedades de transmisión sexual mas frecuente en el mundo. Donde los hombres están implicados en la cadena epidemiológica. Actuando a la vez, como portadores y vectores del HPV oncogénico. Por lo tanto los compañeros sexuales de la mujer que hace la enfermedad contribuyen como un factor de riesgo importante en el desarrollo del cáncer de cérvix. Es un estudio longitudinal prospectivo analítico realizado en el periodo de Enero de 2007 a Junio de 2009, los datos se recogieron a través de una encuesta realizada a cada pareja de las pacientes con citología positiva consignando los datos en una ficha codificada y validada. Se realizaron 86 encuestas a las parejas de las pacientes consignadas dentro del estudio, la edad promedio de los encuestados fue 45 años, 55.8% iniciaron sus relaciones sexuales antes de los 20 años, 47.6% tuvieron contacto sexual con mas de 10 mujeres en el transcurso de su vida, 79% tuvieron contacto sexual con trabajadoras sexuales, de los cuales 61.2% tomaron los servicios de estas por más de 2 veces, solo el 9.3% que mantuvo relaciones sexuales con trabajadoras sexuales usaron preservativos.


Currently infection with human papilloma virus is considered sexually transmitted disease common in the world. Men are involved in the epidemiological chain. Because they were acting as carriers and vectors of oncogenic HPV. Therefore sexual partners of women who has disease were important risk factor in development cervical cancer. This is prospective longitudinal study made between January 2007 to June 2009, data were collected through survey ,all couple of patients with positive cytology by coded and validated form 86 surveys were conducted with all partners of patientÆs positive cytology .The average age of respondents was 45 years, 55.8% initiated sexual activity before 20 years , 47.6% had sexual contact with more than 10 women in their lifetime, 79% had sexual contact with sex workers women. 61.2% took services of them more than 2 times, only 9.3% who had sex with sex workers women used condoms.


Subject(s)
Humans , Male , Adult , Female , Middle Aged , Risk Factors , Papillomavirus Infections , Uterine Cervical Neoplasms , Sexual Partners , Analytical Epidemiology , Longitudinal Studies , Prospective Studies
19.
Genomics ; 91(2): 165-77, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18055165

ABSTRACT

The Hedgehog (Hh) signaling pathway plays critical instructional roles during embryonic development. Misregulation of Hh/Gli signaling is a major causative factor in human congenital disorders and in a variety of cancers. The zebrafish is a powerful genetic model for the study of Hh signaling during embryogenesis, as a large number of mutants that affect different components of the Hh/Gli signaling system have been identified. By performing global profiling of gene expression in different Hh/Gli gain- and loss-of-function scenarios we identified known (e.g., ptc1 and nkx2.2a) and novel Hh-regulated genes that are differentially expressed in embryos with altered Hh/Gli signaling function. By uncovering changes in tissue-specific gene expression, we revealed new embryological processes that are influenced by Hh signaling. We thus provide a comprehensive survey of Hh/Gli-regulated genes during embryogenesis and we identify new Hh-regulated genes that may be targets of misregulation during tumorigenesis.


Subject(s)
Embryo, Nonmammalian , Gene Expression Regulation, Developmental , Hedgehog Proteins/genetics , Oncogene Proteins/genetics , Trans-Activators/genetics , Animals , Gene Expression Profiling , Neoplasms/etiology , Neoplasms/genetics , Signal Transduction , Tissue Distribution , Zebrafish , Zinc Finger Protein GLI1
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