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1.
Pediatr Res ; 95(2): 558-565, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37658124

RESUMO

BACKGROUND: To characterize neurodevelopmental abnormalities in children up to 36 months of age with congenital Zika virus exposure. METHODS: From the U.S. Zika Pregnancy and Infant Registry, a national surveillance system to monitor pregnancies with laboratory evidence of Zika virus infection, pregnancy outcomes and presence of Zika associated birth defects (ZBD) were reported among infants with available information. Neurologic sequelae and developmental delay were reported among children with ≥1 follow-up exam after 14 days of age or with ≥1 visit with development reported, respectively. RESULTS: Among 2248 infants, 10.1% were born preterm, and 10.5% were small-for-gestational age. Overall, 122 (5.4%) had any ZBD; 91.8% of infants had brain abnormalities or microcephaly, 23.0% had eye abnormalities, and 14.8% had both. Of 1881 children ≥1 follow-up exam reported, neurologic sequelae were more common among children with ZBD (44.6%) vs. without ZBD (1.5%). Of children with ≥1 visit with development reported, 46.8% (51/109) of children with ZBD and 7.4% (129/1739) of children without ZBD had confirmed or possible developmental delay. CONCLUSION: Understanding the prevalence of developmental delays and healthcare needs of children with congenital Zika virus exposure can inform health systems and planning to ensure services are available for affected families. IMPACT: We characterize pregnancy and infant outcomes and describe neurodevelopmental abnormalities up to 36 months of age by presence of Zika associated birth defects (ZBD). Neurologic sequelae and developmental delays were common among children with ZBD. Children with ZBD had increased frequency of neurologic sequelae and developmental delay compared to children without ZBD. Longitudinal follow-up of infants with Zika virus exposure in utero is important to characterize neurodevelopmental delay not apparent in early infancy, but logistically challenging in surveillance models.


Assuntos
Microcefalia , Transtornos do Neurodesenvolvimento , Complicações Infecciosas na Gravidez , Infecção por Zika virus , Zika virus , Lactente , Recém-Nascido , Gravidez , Criança , Feminino , Humanos , Pré-Escolar , Infecção por Zika virus/complicações , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/congênito , Complicações Infecciosas na Gravidez/epidemiologia , Microcefalia/epidemiologia , Transtornos do Neurodesenvolvimento/complicações
2.
Int J Mol Sci ; 15(2): 2172-90, 2014 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-24481065

RESUMO

Glioblastomas (GBM) are very aggressive and malignant brain tumors, with frequent relapses despite an appropriate treatment combining surgery, chemotherapy and radiotherapy. In GBM, hypoxia is a characteristic feature and activation of Hypoxia Inducible Factors (HIF-1α and HIF-2α) has been associated with resistance to anti-cancer therapeutics. Int6, also named eIF3e, is the "e" subunit of the translation initiation factor eIF3, and was identified as novel regulator of HIF-2α. Eukaryotic initiation factors (eIFs) are key factors regulating total protein synthesis, which controls cell growth, size and proliferation. The functional significance of Int6 and the effect of Int6/EIF3E gene silencing on human brain GBM has not yet been described and its role on the HIFs is unknown in glioma cells. In the present study, we show that Int6/eIF3e suppression affects cell proliferation, cell cycle and apoptosis of various GBM cells. We highlight that Int6 inhibition induces a diminution of proliferation through cell cycle arrest and increased apoptosis. Surprisingly, these phenotypes are independent of global cell translation inhibition and are accompanied by decreased HIF expression when Int6 is silenced. In conclusion, we demonstrate here that Int6/eIF3e is essential for proliferation and survival of GBM cells, presumably through modulation of the HIFs.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Fator de Iniciação 3 em Eucariotos/genética , Glioblastoma/genética , Glioblastoma/mortalidade , Apoptose/genética , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Fator de Iniciação 3 em Eucariotos/metabolismo , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Modelos Biológicos , Interferência de RNA
3.
Oncotarget ; 9(8): 8054-8067, 2018 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-29487714

RESUMO

Atypical teratoid/rhabdoid tumors (AT/RT) are highly aggressive, malignant tumors and are the most common malignant brain tumor in children under 6 months of age. Currently, there is no standard treatment for AT/RT. Recent studies have reported potential anti-tumoral properties of ribavirin, a guanosine analog and anti-viral molecule approved by the Food and Drug Administration for treatment of hepatitis C. We previously demonstrated that ribavirin inhibited glioma cell growth in vitro and in vivo. Based on these results and the fact that no pre-clinical model of ribavirin in AT/RT exists, we decided to investigate the effect of ribavirin on several human AT/RT cell lines (BT12, BT16, and BT37) both in vitro and in vivo. We provide evidence that ribavirin has a significant impact on AT/RT cell growth and increases cell cycle arrest and cell death, potentially through modulation of the eIF4E and/or EZH2 pathways. Interestingly, using scratch wound and transwell Boyden chamber assays, we observed that ribavirin also impairs AT/RT cell migration, invasion, and adhesion. Finally, we demonstrate that ribavirin significantly improves the survival of mice orthotopically implanted with BT12 cells. Our work establishes that ribavirin is effective against AT/RT by decreasing tumoral cell growth and dissemination and could represent a new therapeutic option for children with this deadly disease.

4.
Front Biosci (Landmark Ed) ; 22(1): 1-20, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27814599

RESUMO

Recent research on translation and protein synthesis in several pathologies, including cancer, peripheral artery disease, and wound healing, demonstrates the key role played by translational factors in tumorigenic and angiogenic processes. This review will focus on one specific translational factor, eIF3e also called INT6, the "e" subunit of the translation initiation factor eIF3. INT6/eIF3e has recently been described as a multifunction protein playing a role in translation, protein degradation, DNA repair, nonsense-mediated mRNA decay, cell cycle and control of cell response to low oxygen (hypoxia or ischemia) through modulation of the Hypoxia Inducible Factors (HIFs). Interestingly, INT6/eIF3e is a double-edged sword that has both oncogenic and tumor suppressive abilities. In addition to its role in tumorigenesis, its silencing has recently been suggested as a potential therapeutic strategy to improve cell survival and function after ischemic injuries. Although a deeper understanding of the molecular mechanisms involved in these pathophysiological functions is essential, particularly to transform the in vitro/in vivo findings into clinical applications, INT6/eIF3e modulation could provide therapeutic benefit for a variety of human diseases such as cancer or vascular diseases.


Assuntos
Fator de Iniciação 3 em Eucariotos/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Transição Epitelial-Mesenquimal/genética , Transição Epitelial-Mesenquimal/fisiologia , Fator de Iniciação 3 em Eucariotos/química , Fator de Iniciação 3 em Eucariotos/genética , Genes Supressores de Tumor , Humanos , Neoplasias/irrigação sanguínea , Neoplasias/genética , Neoplasias/metabolismo , Neovascularização Patológica , Neovascularização Fisiológica , Oncogenes , Subunidades Proteicas
5.
PLoS One ; 10(4): e0123721, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25867026

RESUMO

High-grade gliomas, glioblastomas (GB), are refractory to conventional treatment combining surgery, chemotherapy, mainly temozolomide, and radiotherapy. This highlights an urgent need to develop novel therapies and increase the efficacy of radio/chemotherapy for these very aggressive and malignant brain tumors. Recently, tumor metabolism became an interesting potential therapeutic target in various cancers. Accordingly, combining drugs targeting cell metabolism with appropriate chemotherapeutic agents or radiotherapy has become attractive. In light of these perspectives, we were particularly interested in the anti-cancer properties of a biguanide molecule used for type 2 diabetes treatment, metformin. In our present work, we demonstrate that metformin decreases mitochondrial-dependent ATP production and oxygen consumption and increases lactate and glycolytic ATP production. We show that metformin induces decreased proliferation, cell cycle arrest, autophagy, apoptosis and cell death in vitro with a concomitant activation of AMPK, Redd1 and inhibition of the mTOR pathway. Cell sensitivity to metformin also depends on the genetic and mutational backgrounds of the different GB cells used in this study, particularly their PTEN status. Interestingly, knockdown of AMPK and Redd1 with siRNA partially, but incompletely, abrogates the induction of apoptosis by metformin suggesting both AMPK/Redd1-dependent and -independent effects. However, the primary determinant of the effect of metformin on cell growth is the genetic and mutational backgrounds of the glioma cells. We further demonstrate that metformin treatment in combination with temozolomide and/or irradiation induces a synergistic anti-tumoral response in glioma cell lines. Xenografts performed in nude mice demonstrate in vivo that metformin delays tumor growth. As current treatments for GB commonly fail to cure, the need for more effective therapeutic options is overwhelming. Based on these results, metformin could represent a potential enhancer of the cytotoxic effects of temozolomide and/or radiotherapy.


Assuntos
Neoplasias Encefálicas/patologia , Divisão Celular/efeitos dos fármacos , Glioblastoma/patologia , Metformina/farmacologia , Adenilato Quinase/metabolismo , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias Encefálicas/radioterapia , Linhagem Celular Tumoral , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Sinergismo Farmacológico , Glioblastoma/radioterapia , Glicólise/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Temozolomida , Fatores de Transcrição/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
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