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1.
Science ; 364(6440)2019 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-31073041

RESUMO

During corticogenesis, distinct subtypes of neurons are sequentially born from ventricular zone progenitors. How these cells are molecularly temporally patterned is poorly understood. We used single-cell RNA sequencing at high temporal resolution to trace the lineage of the molecular identities of successive generations of apical progenitors (APs) and their daughter neurons in mouse embryos. We identified a core set of evolutionarily conserved, temporally patterned genes that drive APs from internally driven to more exteroceptive states. We found that the Polycomb repressor complex 2 (PRC2) epigenetically regulates AP temporal progression. Embryonic age-dependent AP molecular states are transmitted to their progeny as successive ground states, onto which essentially conserved early postmitotic differentiation programs are applied, and are complemented by later-occurring environment-dependent signals. Thus, epigenetically regulated temporal molecular birthmarks present in progenitors act in their postmitotic progeny to seed adult neuronal diversity.


Assuntos
Neocórtex/embriologia , Células-Tronco Neoplásicas/citologia , Neurogênese/fisiologia , Neurônios/citologia , Animais , Epigênese Genética , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Neocórtex/citologia , Células-Tronco Neoplásicas/metabolismo , Neurogênese/genética , Neurônios/metabolismo , Complexo Repressor Polycomb 2/metabolismo , RNA Mensageiro/metabolismo , Análise de Sequência de RNA , Análise de Célula Única , Transcrição Gênica
2.
Brain Inj ; 31(8): 1050-1060, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28481652

RESUMO

PRIMARY OBJECTIVE: To investigate the type of emotional and behavioural impact that having a parent with a severe acquired brain injury (ABI) has on children during the first period of adjustment. METHODS AND PROCEDURE: The study involved 25 couples in which one of the spouses was affected by ABI, and their 35 children (3-14 years). The children attended three sessions with a psychologist aimed at identifying their spontaneous playing and relational behaviour by means of a grid created on the basis of ICD-10 criteria. Both members of each parental couple attended a session with the psychologist, and were administered the Dyadic Adjustment Scale, the 36-item Health Survey and the Caregiver Burden Inventory. RESULTS: 63% of the children showed signs of emotional suffering, the presence of which was underestimated by their parents on the basis of the psychologist's assessments. The variables that correlated most closely with the children's psychological condition were related to the quality of their parents' relationship. CONCLUSIONS: Our findings confirm the need for early interventions aimed at both parents and their children in order to investigate the children's emotional-affective situation, and favour an understanding of their discomfort by their parents.


Assuntos
Lesões Encefálicas , Comportamento Infantil/fisiologia , Relações Pais-Filho , Pais/psicologia , Estresse Psicológico/etiologia , Estresse Psicológico/psicologia , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Psicológicos , Estudos Retrospectivos
4.
Phytomedicine ; 17(5): 356-62, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20149610

RESUMO

We investigated the anticancer effect of EGCG treatment on a breast carcinoma cell line resistant to tamoxifen (MCF-7Tam cells). As there are no reports about the molecular mechanisms implicated in EGCG treatment of tamoxifen resistant breast carcinoma cells, we studied the effects of EGCG treatment on three plasma membrane proteins that are involved in the mechanism of drug-resistance: Multidrug Resistance Protein (MRP1), P-glycoprotein (P-gp) and Breast Cancer Resistance Protein (BCRP). EGCG treatment (10-100 microg/ml for 24-72 hours) caused cell growth inhibition and dose-dependent apoptosis: after 100 microg/ml EGCG treatment for 24 hours, Bax expression increased and Bcl2 expression decreased (p<0.05). Coherently, Annexin V-FITC apoptosis assay detected a significant increase in labelled cells (p<0.05). EGCG did not affect MRP1: in contrast, 100 microg/ml EGCG administration caused P-gp decrease to 53% of control cells (p<0.001) and this effect was not due to downregulation of P-gp gene expression. EGCG induced P-gp decrease even when MG132, a strong proteasome inhibitor, was given together with EGCG to MCF-7Tam cells. EGCG treatment also inhibited BCRP activity: mRNA transcription and protein level did not change after treatment, but mitoxantrone test demonstrated a strong inhibition of BCRP activity (p<0.001). In conclusion, the present results showed that EGCG could down-regulate the activity of two molecules that play a key role in drug metabolism and transport and that are highly expressed in tamoxifen resistant breast carcinoma cells. The interaction of EGCG and drugs used in the therapy of estrogen sensitive breast carcinoma ought to be subject of studies and the potential use of EGCG in drug-resistant diseases ought to be better considered.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Catequina/análogos & derivados , Proteínas de Neoplasias/metabolismo , Extratos Vegetais/uso terapêutico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Camellia sinensis/química , Catequina/farmacologia , Catequina/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Expressão Gênica , Humanos , Leupeptinas/farmacologia , Mitoxantrona/farmacologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteínas de Neoplasias/genética , Extratos Vegetais/farmacologia , Inibidores de Proteases/farmacologia , Inibidores de Proteases/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/metabolismo , Tamoxifeno , Proteína X Associada a bcl-2/metabolismo
5.
Placenta ; 29(8): 660-70, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18617261

RESUMO

We have tested the hypothesis that human early trophoblast is a target for somatostatin (SRIF) regulatory actions. We report for the first time that SSTR2A and 2B transcripts and proteins are present in first-trimester human chorionic villi and the trophoblast-derived HTR-8/SVneo and JAR cells. In both cell lines, SSTR are functional since SRIF inhibits cyclic AMP pathway, stimulates arachidonic acid release and enhances cell proliferation. Moreover, in HTR-8/SVneo cells, considered a good model of first-trimester EVT, SRIF also enhances migration. An involvement of the cyclic AMP pathway in mediating SRIF effects on proliferation and migration is suggested. Our data support the idea that SRIF regulates early trophoblast functions mainly through an interaction with SSTR2.


Assuntos
Primeiro Trimestre da Gravidez/fisiologia , Somatostatina/fisiologia , Trofoblastos/fisiologia , Diferenciação Celular/genética , Proliferação de Células , Células Cultivadas , AMP Cíclico/metabolismo , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez/genética , Primeiro Trimestre da Gravidez/metabolismo , Receptores de Somatostatina/genética , Receptores de Somatostatina/metabolismo , Receptores de Somatostatina/fisiologia , Somatostatina/metabolismo , Trofoblastos/metabolismo
6.
Anticancer Res ; 28(1A): 283-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18383858

RESUMO

All-trans retinoic acid (RA) induces complete remission in a high proportion of patients with acute promyelocytic leukemia (APL). Nevertheless, most of these patients develop RA resistance and relapse. In an attemp to mimic clinical conditions for the treatment of leukemia, a stably RA-resistant subclone of the human promyelocytic leukemia cell line HL60 (HL60-R) was developed to study the antiproliferative and proapoptotic effect of the retinoid IIF (6-OH-11-O-hydroxyphenantrene) in comparison with RA. Moreover whether the inhibitor of histone deacetylase (HDAC) activity, valproic acid (VPA), could enhance sensitivity to retinoids in HL60-R cells was evaluated. Finally, the effect of IIF on the expression of multidrug resistance-associated protein 1 (MRP1) and P-glycoprotein (P-gp) was evaluated. It was found that IIF strongly suppressed cell proliferation (as measured by growth curves) and induced apoptosis (as measured by DNA fragmentation and Annexin V detection assays), while RA was practically ineffective. The addition of VPA to IIF accentuated the antiproliferative effect of IIF alone and increased apoptosis; the combination of VPA with RA allowed growth arrest. Moreover IIF caused a reduction of transmembrane transporter expression, particularly of P-gp, as shown by Western blotting. Our results suggest that IIF may be useful in controlling the proliferation of RA-resistant leukemia cells, especially in combination with an HDAC inhibitor, such as VPA.


Assuntos
Leucemia Promielocítica Aguda/tratamento farmacológico , Tretinoína/análogos & derivados , Tretinoína/farmacologia , Ácido Valproico/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Apoptose/efeitos dos fármacos , Processos de Crescimento Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Células HL-60 , Humanos , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/biossíntese
7.
Oncol Rep ; 18(4): 1015-21, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17786368

RESUMO

Glioblastomas, the most malignant and prevalent brain tumors which remain incurable, are characterized by both extensive proliferation and invasive growth. We previously reported a remarkable antitumoral effect of the retinoid 6-OH-11-O-hydroxyphenantrene (IIF) on neuroblastoma, leukemia and colon carcinoma cells. In this study we examined the effect of IIF on proliferation, apoptosis and cell invasion in the human glioblastoma cell line U87MG, in comparison with all-trans-retinoic acid (RA). Our results showed that both retinoids induced cell growth inhibition and apoptosis in a dose- and time-dependent manner. We also demonstrated that the invasive ability of glioblastoma cells decreased after treatment with IIF or RA. Since cell invasion involves a complex system of tightly regulated proteases, matrix metalloproteinases (MMPs) and their specific inhibitors, tissue inhibitors of MMPs (TIMPs), we analysed the effect of IIF on MMP and TIMP expression in comparison with RA. Treatment with both retinoids resulted in a marked decrease of MMP2 and MMP9 expression and of lytic activity of MMP2. In addition, exposure to IIF led to enhanced expression of TIMP2. Collectively, our results demonstrated the effectiveness of both IIF and RA in inhibiting proliferation, cell migration, and the invasive potential of glioblastoma U87MG cells. Notably, the anticancer activity of IIF, on the whole, was more pronounced than that of RA. Therefore, these findings, besides providing further evidence that IIF may be a powerful tool in the development of cancer treatments, suggest that IIF may have therapeutic potential against the invasiveness of brain tumors.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Tretinoína/análogos & derivados , Tretinoína/farmacologia , Anexina A5/metabolismo , Western Blotting , Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Invasividade Neoplásica/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Inibidor Tecidual de Metaloproteinase-2/genética , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/patologia
8.
In Vivo ; 20(6A): 729-33, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17203756

RESUMO

The development of multidrug resistance (MDR) is one of the major causes of failure in cancer therapy. The use of cell lines with acquired resistance to anticancer agents represents a very good tool for investigation into the possibility of reversal of MDR. In this study the ability of all-trans-retinoic acid (RA) and its derivative 6-OH-11-O-hydroxyphenanthrene (IIF; pat. WIPO W000 /117143) as antitumor agents was investigated in the human colon carcinoma cell line LoVo and in the counterpart resistant derivative LoVo/MDR cell line. Cell proliferation was measured by MTT assay, apoptosis was evaluated using DNA fragmentation and Annexin V detection assay. Retinoids suppressed cell proliferation in a time- and dose-dependent manner. Interestingly, IIF was significantly more effective than RA, particularly on LoVo/MDR cells. RA and IIF induced apoptosis in both cell lines, with IIF effect significantly higher than that of RA. Furthermore, on the basis that MDR phenotype is often caused by drug efflux due to overexpression of the membrane P-glycoprotein (P-gp), it was demonstrated that RA and IIF reduced P-gp synthesis in LoVo/MDR cells. Our results suggest that IIF could be a powerful tool in the development of colon carcinoma treatments, even when tumor cells present an MDR phenotype.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Tretinoína/análogos & derivados , Tretinoína/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Relação Dose-Resposta a Droga , Formazans/metabolismo , Humanos , Sais de Tetrazólio/metabolismo
9.
Anticancer Res ; 24(3a): 1779-83, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15274355

RESUMO

Vitamin A and its metabolic forms, like all-trans retinoic acid (ATRA), are used with promising results in the treatment of many tumors. Two major problems in the clinical use of retinoids are that the doses needed for successful treatment are often toxic, leading to "hypervitaminosis A syndrome" and that patients often develop drug resistance. In order to find compounds that can overcome these problems, many new derivatives of retinoids have been synthesized and tested. Here we present a study on the effect of a new derivative of retinoic acid, IIF (pat. WIPO W0 00/17143), on growth and differentiation of two colon carcinomna cell lines, CaCo-2 and HT-29, with different degrees of tumorigenicity, the second one being more undifferentiated. The effect of IIF was compared with that of ATRA, whose antitumoral action on colon cancer cells and other tumoral cells is widely described in the literature. Besides exerting a strong antiproliferative effect, even higher than that of ATRA, IIF induced cellular differentiation, as demonstrated by the appearance of morphological (domes and microvilli formation) and biochemical (alkaline phosphatase induction) markers. Therefore, these findings indicate the new retinoid IIF as a possible candidate in the treatment of colon cancer.


Assuntos
Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Tretinoína/análogos & derivados , Tretinoína/farmacologia , Células CACO-2 , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Células HT29 , Humanos
10.
Lipids ; 39(2): 135-41, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15134140

RESUMO

The purpose of this study was to examine the effects of two purified isomers of CLA (c9,t11-CLA and t10,c12-CLA) on the weights and FA compositions of hepatic TG, phospholipids, cholesterol esters, and FFA. Eight-week-old female mice (n = 6/group) were fed either a control diet or diets supplemented with 0.5% c9,t11-CLA or t10,c12-CLA isomers for 8 wk. Weights of liver total lipids and those of individual lipid fractions did not differ between the control and the c9,t11-CLA groups. Livers from animals fed the t10, c12-CLA diet contained four times more lipids than those of the control group; this was mainly due to an increase in the TG fractions (fivefold), but cholesterol (threefold), cholesterol esters (threefold), and FFA (twofold) were also significantly increased. Although c9,t11-CLA did not significantly alter the weights of liver lipids when compared with the control group, its intake was associated with significant reductions in the weight percentage (wt% of total FAME) of 18:1n-9 and 18:1n-7 in the TG fraction and with significant increases in the weight percentage of 18:2n-6 in the TG, cholesterol ester, and phospholipid fractions. On the other hand, t10,c12-CLA intake was linked with a significant increase in the weight percentage of 18:1n-9 and a decrease in that of 18:2n-6 in all lipid fractions. These changes may be the result of alterations in the activity of delta9-desaturase (stearoyl CoA desaturase) and the enzymes involved in the metabolism of 18:2n-6. Thus, the two isomers differed not only in their effects on the weights of total liver lipids and lipid fractions but also on the FA profile of the lipid fractions.


Assuntos
Ácidos Graxos/análise , Ácidos Linoleicos/farmacologia , Lipídeos/análise , Fígado/química , Animais , Ésteres do Colesterol/análise , Ésteres do Colesterol/química , Ácidos Graxos/química , Feminino , Ácidos Linoleicos/química , Lipídeos/química , Camundongos , Camundongos Endogâmicos C57BL , Fosfolipídeos/análise , Fosfolipídeos/química , Estereoisomerismo , Triglicerídeos/análise , Triglicerídeos/química
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