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1.
PLoS One ; 15(5): e0233528, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32437468

RESUMO

BACKGROUND & AIM: Worldwide, measures are being implemented to eradicate hepatitis B (HBV) and C (HCV) viruses, which can be transmitted from the mother during childbirth. This study aims to determine the prevalence of HBV and HCV in pregnant women in Spain, focusing on country of origin, epidemiological factors and risk of vertical transmission (VT). METHODOLOGY: Multicentre open-cohort study performed during 2015. HBV prevalence was determined in 21870 pregnant women and HCV prevalence in 7659 pregnant women. Epidemiological and risk factors for VT were analysed in positive women and differences between HBV and HCV cases were studied. RESULTS: HBV prevalence was 0.42% (91/21870) and HCV prevalence was 0.26% (20/7659). Of the women with HBV, 65.7% (44/67) were migrants. The HBV transmission route to the mother was unknown in 40.3% of cases (27/67) and VT in 31.3% (21/67). Among risk factors for VT, 67.7% (42/62) of the women had viraemia and 14.5% (9/62) tested HBeAg-positive. All of the neonates born to HBV-positive mothers received immunoprophylaxis, and none contracted infection by VT. In 80% (16/20) of the women with HCV, the transmission route was parenteral, and nine were intravenous drug users. Viraemia was present in 40% (8/20) of the women and 10% (2/20) were HIV-coinfected. No children were infected. Women with HCV were less likely than women with HBV to breastfeed their child (65% vs. 86%). CONCLUSIONS: The prevalences obtained in our study of pregnant women are lower than those previously documented for the general population. Among the women with HBV, the majority were migrants and had a maternal family history of infection, while among those with HCV, the most common factor was intravenous drug use. Despite the risk factors observed for VT, none of the children were infected. Proper immunoprophylaxis is essential to prevent VT in children born to HBV-positive women.


Assuntos
Hepatite B/epidemiologia , Hepatite C/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Estudos de Coortes , Feminino , Hepacivirus/isolamento & purificação , Hepatite B/transmissão , Vírus da Hepatite B/isolamento & purificação , Hepatite C/transmissão , Humanos , Transmissão Vertical de Doenças Infecciosas , Gravidez , Fatores de Risco , Estudos Soroepidemiológicos , Espanha
2.
Curr Med Chem ; 24(20): 2156-2173, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28302009

RESUMO

Poly(ADP-ribose) polymerase-1 (PARP-1) is a nuclear enzyme that plays a critical role in diverse cellular functions, such as DNA damage detection and repair, transcriptional regulation and cell death. Furthermore, PARP-1 has emerged as a key player in the pathogenesis of multiple inflammatory diseases and has become a promising target for the treatment of cardiovascular disorders, neurodegenerative diseases and cancer. An increasing body of evidence has linked alterations in the expression levels of PARP-1, enzymatic activity and presence of polymorphism to gastrointestinal malignancies, including oesophageal, gastric, pancreas, liver and colorectal cancers. PARP inhibition has been proposed as a valuable strategy for treating these gastrointestinal disorders. This paper summarises the most significant current literature on the involvement of PARP-1 in gastrointestinal cancer, focusing in particular on its role in the development and occurrence of tumours, providing information about clinical trials and exploring therapeutic possibilities.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Gastrointestinais/tratamento farmacológico , Neoplasias Gastrointestinais/genética , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/patologia , Poli(ADP-Ribose) Polimerase-1/genética , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Polimorfismo de Nucleotídeo Único , Animais , Antineoplásicos/farmacologia , Descoberta de Drogas , Neoplasias Gastrointestinais/patologia , Trato Gastrointestinal/metabolismo , Humanos , Terapia de Alvo Molecular , Poli(ADP-Ribose) Polimerase-1/análise , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia
3.
Med. clín (Ed. impr.) ; 147(11): 499-505, dic. 2016. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-158471

RESUMO

La infección crónica por el virus de la hepatitis C (VHC) ha sido reconocida como un problema de salud mundial. Constituye la principal causa de cirrosis, carcinoma hepatocelular y trasplante hepático. Su prevalencia en gestantes es similar a la de la población general y no se asocia con complicaciones obstétricas. La transmisión vertical del VHC (TV-VHC) constituye la vía principal de infección en niños en países desarrollados (> 90%), si bien, el porcentaje de TV-VHC y cronificación es relativamente bajo (3-8%). Sin embargo, la TV-VHC aumenta hasta el 15-20% en madres coinfectadas con el virus de la inmunodeficiencia humana. En esta revisión se analizará la historia natural de la infección en la gestación y en el niño, los factores de riesgo de TV-VHC, los métodos de diagnóstico/seguimiento recomendados y las nuevas posibilidades de tratamiento con antivirales de acción directa, factores claves para la creación de futuras guías clínicas (AU)


Hepatitis C virus (HCV) infection has been recognised as a worldwide health problem. HCV is the most common cause of cirrhosis, hepatocellular carcinoma and liver transplantation. The HCV prevalence reported in pregnant women is similar to that found among the general population and does not appear to have an adverse effect on the course of pregnancy. The vertical transmission of HCV (HCV-VT) is a major route of HCV infection in children in the developed countries (> 90%). The overall rate of mother-to- child transmission and chronification is about 3%-8%; however, this rate is higher for mothers who are co-infected with the human immunodeficiency virus (15-20%). In this review, we analyse the course of HCV infection during gestation, the risk factors associated with HCV-VT, the diagnostic methods/clinical monitoring recommended and the new possibilities of treatment in the era of directacting antiviral agents, which are essential to guide future public health efforts appropriately (AU)


Assuntos
Humanos , Feminino , Gravidez , Hepatite C Crônica/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Antivirais/uso terapêutico , Hepacivirus/patogenicidade , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Fatores de Risco
4.
Med Clin (Barc) ; 147(11): 499-505, 2016 Dec 02.
Artigo em Espanhol | MEDLINE | ID: mdl-27209226

RESUMO

Hepatitis C virus (HCV) infection has been recognised as a worldwide health problem. HCV is the most common cause of cirrhosis, hepatocellular carcinoma and liver transplantation. The HCV prevalence reported in pregnant women is similar to that found among the general population and does not appear to have an adverse effect on the course of pregnancy. The vertical transmission of HCV (HCV-VT) is a major route of HCV infection in children in the developed countries (>90%). The overall rate of mother-to-child transmission and chronification is about 3%-8%; however, this rate is higher for mothers who are co-infected with the human immunodeficiency virus (15-20%). In this review, we analyse the course of HCV infection during gestation, the risk factors associated with HCV-VT, the diagnostic methods/clinical monitoring recommended and the new possibilities of treatment in the era of direct-acting antiviral agents, which are essential to guide future public health efforts appropriately.


Assuntos
Hepatite C Crônica , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez , Antivirais/uso terapêutico , Europa (Continente)/epidemiologia , Feminino , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/transmissão , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/epidemiologia , Cuidado Pré-Natal/métodos , Prevalência , Fatores de Risco , Estados Unidos/epidemiologia
5.
Int J Radiat Biol ; 91(12): 946-56, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26490761

RESUMO

PURPOSE: To evaluate matrix metalloproteinase (MMP) activity and invasion after ionizing radiation (IR) exposure and to determine whether MMP could be epigenetically modulated by histone deacetylase (HDAC) inhibition. MATERIAL AND METHODS: Two human breast cancer cell lines (MDA-MB-231 and MCF-7) were cultured in monolayer (2D) and in laminin-rich extracellular matrix (3D). Invasion capability, collagenolytic and gelatinolytic activity, MMP and TIMP protein and mRNA expression and clonogenic survival were analyzed after IR exposure, with and without a HDAC inhibition treatment [1.5 mM valproic acid (VA) or 1 µM trichostatin-A (TSA)]. RESULTS: IR exposure resulted in cell line-dependent stimulation of invasion capacity. In contrast to MCF-7 cells, irradiated MDA-MB-231 showed significantly enhanced mRNA expression of mmp-1, mmp-3 and mmp-13 and of their regulators timp-1 and timp-2 relative to unirradiated controls. This translated into increased collagenolytic and gelatinolytic activity and could be reduced after valproic acid (VA) treatment. Additionally, VA also mitigated IR-enhanced mmp and timp mRNA expression as well as IR-increased invasion capability. Finally, our data confirm the radiosensitizing effect of VA. CONCLUSION: These results suggest that IR cell line-dependently induces upregulation of MMP mRNA expression, which appears to be mechanistically linked to a higher invasion capability that is modifiable by HDAC inhibition.


Assuntos
Inibidores de Histona Desacetilases/farmacologia , Metaloproteinases da Matriz/metabolismo , Ácido Valproico/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Raios Infravermelhos/uso terapêutico , Células MCF-7 , Metaloproteinases da Matriz/genética , Invasividade Neoplásica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Tolerância a Radiação/efeitos dos fármacos , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-2/genética
6.
PLoS One ; 8(10): e75613, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24130726

RESUMO

This study analyses the evolution of liver disease in women with chronic hepatitis C during the third trimester of pregnancy and the post-partum period, as a natural model of immune modulation and reconstitution. Of the 122 mothers recruited to this study, 89 were HCV-RNA+ve/HIV-ve and 33 were HCV-RNA-ve/HIV-ve/HCVantibody+ve and all were tested during the third trimester of pregnancy, at delivery and post-delivery. The HCV-RNA+ve mothers were categorized as either Type-A (66%), with an increase in ALT levels in the post-partum period (>40 U/L; P<0.001) or as Type-B (34%), with no variation in ALT values. The Type-A mothers also presented a significant decrease in serum HCV-RNA levels in the post-delivery period (P<0.001) and this event was concomitant with an increase in Th1 cytokine levels (INFγ, P = 0.04; IL12, P = 0.01 and IL2, P = 0.01). On the other hand, the Type-B mothers and the HCV-RNA-ve women presented no variations in either of these parameters. However, they did present higher Th1 cytokine levels in the partum period (INFγ and IL2, P<0.05) than both the Type-A and the HCV-RNA-ve women. Cytokine levels at the moment of delivery do not constitute a risk factor associated with HCV vertical transmission. It is concluded that differences in the ALT and HCV-RNA values observed in HCV-RNA+ve women in the postpartum period might be due to different ratios of Th1 cytokine production. In the Type-B women, the high partum levels of Th1 cytokines and the absence of post-partum variation in ALT and HCV-RNA levels may be related to permanent Th1 cytokine stimulation.


Assuntos
Alanina Transaminase/metabolismo , Hepacivirus/genética , Hepatite C Crônica/virologia , RNA Viral/genética , Adulto , Alanina Transaminase/genética , Feminino , Genótipo , Hepacivirus/imunologia , Hepatite C Crônica/imunologia , Humanos , Transmissão Vertical de Doenças Infecciosas , Interferons , Interleucinas/genética , Período Pós-Parto , Gravidez , Equilíbrio Th1-Th2
9.
Cell Res ; 22(7): 1181-98, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22525338

RESUMO

In response to nutrient stress, cells start an autophagy program that can lead to adaptation or death. The mechanisms underlying the signaling from starvation to the initiation of autophagy are not fully understood. In the current study we show that the absence or inactivation of PARP-1 strongly delays starvation-induced autophagy. We have found that DNA damage is an early event of starvation-induced autophagy as measured by γ-H2AX accumulation and comet assay, with PARP-1 knockout cells displaying a reduction in both parameters. During starvation, ROS-induced DNA damage activates PARP-1, leading to ATP depletion (an early event after nutrient deprivation). The absence of PARP-1 blunted AMPK activation and prevented the complete loss of mTOR activity, leading to a delay in autophagy. PARP-1 depletion favors apoptosis in starved cells, suggesting a pro-survival role of autophagy and PARP-1 activation after nutrient deprivation. In vivo results show that neonates of PARP-1 mutant mice subjected to acute starvation, also display deficient liver autophagy, implying a physiological role for PARP-1 in starvation-induced autophagy. Thus, the PARP signaling pathway is a key regulator of the initial steps of autophagy commitment following starvation.


Assuntos
Autofagia/fisiologia , Dano ao DNA/fisiologia , Poli(ADP-Ribose) Polimerases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Autofagia/genética , Western Blotting , Linhagem Celular , Sobrevivência Celular/genética , Sobrevivência Celular/fisiologia , Dano ao DNA/genética , Imunofluorescência , Camundongos , Microscopia de Fluorescência , Modelos Biológicos , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/genética
10.
Hepatology ; 53(6): 1830-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21413051

RESUMO

UNLABELLED: The vertical transmission of hepatitis C virus (HCV-VT) is a major route of HCV infection in children, but the risk factors remain incompletely understood. This study analyzed the role of interleukin 28B (IL28B) in HCV-VT and in the spontaneous clearance of HCV among infected infants. Between 1991 and 2009, 145 mothers were recruited for this study: 100 were HCV-RNA+ve / human immunodeficiency virus negative (HIV-ve), with 128 children, and 33 were HCV-RNA-ve/HCV antibody+ve, with 43 children. The infants were tested for HCV-RNA at birth and at regular intervals until the age of 6 years. IL28B (single nucleotide polymorphism rs12979860) was determined in the mothers and children. HCV-VT was assumed when children presented HCV-RNA+ve in two subsequent blood samples. HCV-VT-infected infants were categorized as: (1) transient viremia with posterior HCV-RNA-ve and without serum-conversion; (2) persistent infection with serum-conversion. Of the 31 mothers with CC polymorphism, 19 (61%) were HCV-RNA+ve, whereas among the 68 mothers with non-CC polymorphism, 56 (82%) were HCV-RNA+ve. In all, 26 of 128 (20%) infants born to the HCV-RNA+ve mothers acquired HCV infection, but only 9 (7%) were chronically infected. The rate of HCV-VT was higher among the mothers with higher HCV viremia. No HCV-VT was detected in the HCV-RNA-ve women. Neither the mothers' nor the childrens' IL-28 status was associated with an increased risk of HCV-VT. The factors influencing viral clearance among the infected children were genotype non-1 and genotype CC of IL28B. In logistic regression, child CC polymorphism was the only predictor of HCV-clearance in HCV genotype-1. CONCLUSION: High maternal viral load is the only predictive factor of HCV-VT. IL28B plays no role in HCV-VT, but IL28B CC child polymorphism is associated independently with the spontaneous clearance of HCV genotype-1 among infected children.


Assuntos
Hepacivirus , Hepatite C/transmissão , Transmissão Vertical de Doenças Infecciosas , Interleucinas/genética , Polimorfismo de Nucleotídeo Único/genética , Complicações Infecciosas na Gravidez/genética , Criança , Pré-Escolar , Feminino , Genótipo , Hepacivirus/genética , Hepatite C/sangue , Hepatite C/epidemiologia , Humanos , Lactente , Recém-Nascido , Interferons , Modelos Logísticos , Masculino , Valor Preditivo dos Testes , Gravidez , Complicações Infecciosas na Gravidez/sangue , RNA Viral/sangue , Estudos Retrospectivos , Fatores de Risco , Carga Viral
11.
Hepatology ; 51(1): 255-66, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20034026

RESUMO

UNLABELLED: Hepatocellular carcinoma (HCC) is associated with a poor prognosis due to a lack of effective treatment options. In HCC a significant role is played by DNA damage and the inflammatory response. Poly (ADP-ribose) polymerase-1 (PARP-1) is an important protein that regulates both these mechanisms. The objective of this study was to examine the effect of pharmacology PARP-1 inhibition on the reduction of tumor volume of HCC xenograft and on the hepatocarcinogenesis induced by diethyl-nitrosamine (DEN). Pharmacologic PARP-1 inhibition with DPQ greatly reduces tumor xenograft volume with regard to a nontreated xenograft (394 mm(3) versus 2,942 mm(3), P < 0.05). This observation was paralleled by reductions in xenograft mitosis (P = 0.02) and tumor vasculogenesis (P = 0.007, confirmed by in vitro angiogenesis study), as well as by an increase in the number of apoptotic cells in DPQ-treated mice (P = 0.04). A substantial difference in key tumor-related gene expression (transformed 3T3 cell double minute 2 [MDM2], FLT1 [vascular endothelial growth factor receptor-1, VEGFR1], epidermal growth factor receptor [EPAS1]/hypoxia-inducible factor 2 [HIF2A], EGLN1 [PHD2], epidermal growth factor receptor [EGFR], MYC, JUND, SPP1 [OPN], hepatocyte growth factor [HGF]) was found between the control tumor xenografts and the PARP inhibitor-treated xenografts (data confirmed in HCC cell lines using PARP inhibitors and PARP-1 small interfering RNA [siRNA]). Furthermore, the results obtained in mice treated with DEN to induce hepatocarcinogenesis showed, after treatment with a PARP inhibitor (DPQ), a significant reduction both in preneoplastic foci and in the expression of preneoplastic markers and proinflammatory genes (Gstm3, Vegf, Spp1 [Opn], IL6, IL1b, and Tnf), bromodeoxyuridine incorporation, and NF-kappaB activation in the initial steps of carcinogenesis (P < 0.05). CONCLUSION: This study shows that PARP inhibition is capable of controlling HCC growth and preventing tumor vasculogenesis by regulating the activation of different genes involved in tumor progression.


Assuntos
Carcinoma Hepatocelular/patologia , Isoquinolinas/farmacologia , Neoplasias Hepáticas Experimentais/patologia , Piperidinas/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases , Animais , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/tratamento farmacológico , Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Isoquinolinas/uso terapêutico , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Neovascularização Patológica/tratamento farmacológico , Piperidinas/uso terapêutico , Poli(ADP-Ribose) Polimerase-1 , RNA Mensageiro/metabolismo
12.
Autophagy ; 5(1): 61-74, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19001878

RESUMO

Autophagy is a lysosome-dependent degradative pathway frequently activated in tumor cells treated with chemotherapy or radiation. PARP-1 has been implicated in different pathways leading to cell death and its inhibition potentiates chemotherapy-induced cell death. Whether PARP-1 participates in the cell's decision to commit to autophagy following DNA damage is still not known. To address this issue PARP-1 wild-type and deficient cells have been treated with a dose of doxorubicin that induces autophagy. Electron microscopy examination and GFP-LC3 transfection revealed autophagic vesicles and increased expression of genes involved in autophagy (bnip-3, cathepsin b and l and beclin-1) in wild-type cells treated with doxo but not in parp-1(-/-) cells or cells treated with a PARP inhibitor. Mechanistically the lack of autophagic features in PARP-1 deficient/PARP inhibited cells is attributed to prevention of ATP and NAD(+) depletion and to the activation of the key autophagy regulator mTOR. Pharmacological or genetical inhibition of autophagy results in increased cell death, suggesting a protective role of autophagy induced by doxorubicin. These results suggest that autophagy might be cytoprotective during the response to DNA damage and suggest that PARP-1 activation is involved in the cell's decision to undergo autophagy.


Assuntos
Autofagia , Dano ao DNA , Poli(ADP-Ribose) Polimerases/metabolismo , 1-Naftilamina/análogos & derivados , 1-Naftilamina/farmacologia , Células 3T3 , Trifosfato de Adenosina/deficiência , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose , Autofagia/efeitos dos fármacos , Autofagia/genética , Proteína 5 Relacionada à Autofagia , Proteína Beclina-1 , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Ativação Enzimática/efeitos dos fármacos , Deleção de Genes , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Mitocôndrias/ultraestrutura , Modelos Biológicos , NAD/deficiência , Naftalimidas/farmacologia , Necrose/enzimologia , Inibidores de Poli(ADP-Ribose) Polimerases , Proteínas Quinases/metabolismo , Proteínas/metabolismo , Quinolonas/farmacologia , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo , Serina-Treonina Quinases TOR , Regulação para Cima/efeitos dos fármacos
13.
Cancer Biol Ther ; 7(6): 958-65, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18379196

RESUMO

The aim of the present study was to investigate the association between gene hypermethylation and main clinicopathological features of breast cancer, including diagnosis and treatment response. A sensitive SYBR green methylation-specific PCR technique was used to analyze the utility of circulating DNA with CpG island hypermethylation of ESR1, APC, RARB, 14-3-3-sigma and E-cad gene promoter regions as breast cancer biomarkers. Analyses were conducted of preoperative sera from 106 women with breast cancer, 34 with benign breast disease and 74 with no evidence of breast disease and of post-treatment sera from 60 of the breast cancer patients. Mean serum values of methylated ESR1 and 14-3-3-sigma gene promoters significantly differed between breast cancer patients and healthy controls (p = 0.0112 for ESR1 and p = 0.0047 for 14-3-3-sigma). When their results were combined, it was found that hypermethylation of these two genes differentiated between breast cancer patients and healthy controls (p < 0.0001) with a sensitivity of 81% (95% confidence interval: 72-88%) and specificity of 88% (95% CI: 78-94%). Presence of methylated ESR1 in serum of breast cancer patients was associated with the ER negative phenotype (p = 0.0179). Serum hypermethylation at ESR1 and 14-3-3-sigma loci was observed in cancer patients, in situ carcinoma and benign breast disease. No significant differences in methylated ERS1 or 14-3-3-sigma values were observed between pre-surgery and post-treatment measurements. Preliminary clinical applications of this approach have revealed several shortcomings, including a frequent presence of methylated 14-3-3-sigma in sera from women with breast benign disease. These findings cast some doubts on the utility for early cancer diagnosis of highly sensitive techniques to identify hypermethylation of specific gene promoters in DNA extracted from serum. Although numerous issues remain to be resolved, the quantitative measurement of circulating methylated DNA remains a promising tool for cancer risk assessment.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/sangue , Neoplasias da Mama/diagnóstico , Receptor alfa de Estrogênio/metabolismo , Exonucleases/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas 14-3-3 , Estudos de Casos e Controles , Metilação de DNA , DNA de Neoplasias/metabolismo , Progressão da Doença , Exorribonucleases , Feminino , Humanos , Fenótipo , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Sensibilidade e Especificidade , Resultado do Tratamento
14.
BMC Mol Biol ; 8: 29, 2007 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-17459151

RESUMO

ATM and PARP-1 are two of the most important players in the cell's response to DNA damage. PARP-1 and ATM recognize and bound to both single and double strand DNA breaks in response to different triggers. Here we report that ATM and PARP-1 form a molecular complex in vivo in undamaged cells and this association increases after gamma-irradiation. ATM is also modified by PARP-1 during DNA damage. We have also evaluated the impact of PARP-1 absence or inhibition on ATM-kinase activity and have found that while PARP-1 deficient cells display a defective ATM-kinase activity and reduced gamma-H2AX foci formation in response to gamma-irradiation, PARP inhibition on itself is able to activate ATM-kinase. PARP inhibition induced gamma H2AX foci accumulation, in an ATM-dependent manner. Inhibition of PARP also induces DNA double strand breaks which were dependent on the presence of ATM. As consequence ATM deficient cells display an increased sensitivity to PARP inhibition. In summary our results show that while PARP-1 is needed in the response of ATM to gamma irradiation, the inhibition of PARP induces DNA double strand breaks (which are resolved in and ATM-dependent pathway) and activates ATM kinase.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Dano ao DNA , Proteínas de Ligação a DNA/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Difosfato de Adenosina/metabolismo , Animais , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ciclo Celular/genética , Linhagem Celular , Proteínas de Ligação a DNA/genética , Humanos , Camundongos , Camundongos Knockout , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/deficiência , Poli(ADP-Ribose) Polimerases/genética , Ligação Proteica , Proteínas Serina-Treonina Quinases/genética , Proteínas Supressoras de Tumor/genética
15.
Cancer Res ; 66(11): 5744-56, 2006 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16740713

RESUMO

Poly(ADP-ribose) polymerase (PARP)-1, an enzyme that catalyzes the attachment of ADP ribose to target proteins, acts as a component of enhancer/promoter regulatory complexes. In the present study, we show that pharmacologic inhibition of PARP-1 with 3,4-dihydro-5-[4-(1-piperidinyl)butoxyl]-1(2H)-isoquinolinone (DPQ) results in a strong delay in tumor formation and in a dramatic reduction in tumor size and multiplicity during 7,12-dimethylbenz(a)anthracene plus 12-O-tetradecanoylphorbol-13-acetate-induced skin carcinogenesis. This observation was parallel with a reduction in the skin inflammatory infiltrate in DPQ-treated mice and tumor vasculogenesis. Inhibition of PARP also affected activator protein-1 (AP-1) activation but not nuclear factor-kappaB (NF-kappaB). Using cDNA expression array analysis, a substantial difference in key tumor-related gene expression was found between chemically induced mice treated or not with PARP inhibitor and also between wild-type and parp-1 knockout mice. Most important differences were found in gene expression for Nfkbiz, S100a9, Hif-1alpha, and other genes involved in carcinogenesis and inflammation. These results were corroborated by real-time PCR. Moreover, the transcriptional activity of hypoxia-inducible factor-1alpha (HIF-1alpha) was compromised by PARP inhibition or in PARP-1-deficient cells, as measured by gene reporter assays and the expression of key target genes for HIF-1alpha. Tumor vasculature was also strongly inhibited in PARP-1-deficient mice and by DPQ. In summary, this study shows that inhibition of PARP on itself is able to control tumor growth, and PARP inhibition or genetic deletion of PARP-1 prevents from tumor promotion through their ability to cooperate with the activation AP-1, NF-kappaB, and HIF-1alpha.


Assuntos
Transformação Celular Neoplásica/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/prevenção & controle , Animais , Carcinógenos , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/genética , DNA de Neoplasias/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Isoquinolinas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Piperidinas/farmacologia , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/genética , Acetato de Tetradecanoilforbol , Fator de Transcrição AP-1/metabolismo
16.
Breast Cancer Res ; 7(5): R690-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16168114

RESUMO

INTRODUCTION: Radiotherapy outcomes might be further improved by a greater understanding of the individual variations in normal tissue reactions that determine tolerance. Most published studies on radiation toxicity have been performed retrospectively. Our prospective study was launched in 1996 to measure the in vitro radiosensitivity of peripheral blood lymphocytes before treatment with radical radiotherapy in patients with breast cancer, and to assess the early and the late radiation skin side effects in the same group of patients. We prospectively recruited consecutive breast cancer patients receiving radiation therapy after breast surgery. To evaluate whether early and late side effects of radiotherapy can be predicted by the assay, a study was conducted of the association between the results of in vitro radiosensitivity tests and acute and late adverse radiation effects. METHODS: Intrinsic molecular radiosensitivity was measured by using an initial radiation-induced DNA damage assay on lymphocytes obtained from breast cancer patients before radiotherapy. Acute reactions were assessed in 108 of these patients on the last treatment day. Late morbidity was assessed after 7 years of follow-up in some of these patients. The Radiation Therapy Oncology Group (RTOG) morbidity score system was used for both assessments. RESULTS: Radiosensitivity values obtained using the in vitro test showed no relation with the acute or late adverse skin reactions observed. There was no evidence of a relation between acute and late normal tissue reactions assessed in the same patients. A positive relation was found between the treatment volume and both early and late side effects. CONCLUSION: After radiation treatment, a number of cells containing major changes can have a long survival and disappear very slowly, becoming a chronic focus of immunological system stimulation. This stimulation can produce, in a stochastic manner, late radiation-related adverse effects of varying severity. Further research is warranted to identify the major determinants of normal tissue radiation response to make it possible to individualize treatments and improve the outcome of radiotherapy in cancer patients.


Assuntos
Neoplasias da Mama/radioterapia , DNA de Neoplasias/genética , Linfócitos/efeitos da radiação , Pele/efeitos da radiação , Braquiterapia , Radioisótopos de Cobalto/uso terapêutico , Dano ao DNA , DNA de Neoplasias/efeitos dos fármacos , Fracionamento da Dose de Radiação , Feminino , Seguimentos , Humanos , Radioisótopos de Irídio/uso terapêutico , Aceleradores de Partículas , Fatores de Tempo
17.
Biochem J ; 386(Pt 1): 119-25, 2005 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-15456408

RESUMO

p53 deficiency confers resistance to doxo (doxorubicin), a clinically active and widely used antitumour anthracycline antibiotic. The purpose of the present study was to investigate the reversal mechanism of doxo resistance by the potent PARP [poly(ADP-ribose) polymerase] inhibitor ANI (4-amino-1,8-naphthalimide) in the p53-deficient breast cancer cell lines EVSA-T and MDA-MB-231. The effects of ANI, in comparison with doxo alone, on doxo-induced apoptosis, were investigated in matched pairs of EVSA-T or MDA-MB-231 with or without ANI co-treatment. Doxo elicited PARP activation as determined by Western blotting and immunofluorescence of poly(ADP-ribose), and ANI enhanced the cytotoxic activity of doxo 2.3 times and in a caspase-dependent manner. The long-term cytotoxic effect was studied by a colony-forming assay. Using this assay, ANI also significantly potentiates the long-term cytotoxic effect with respect to treatment with doxo alone. Decrease in mitochondrial potential together with an increase in cytochrome c release, association of Bax with the mitochondria and caspase 3 activation were also observed in the presence of ANI. Therefore PARP inhibition may represent a novel way of selectively targeting p53-deficient breast cancer cells. The underlying mechanism is probably a potentiation of unrepaired DNA damage, shifting from DNA repair to apoptosis due to the effective inhibition of PARP activity.


Assuntos
1-Naftilamina/análogos & derivados , 1-Naftilamina/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteínas de Neoplasias/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases , Quinolonas/farmacologia , Proteína Supressora de Tumor p53/deficiência , Neoplasias da Mama/genética , Caspase 3 , Caspases/metabolismo , Sinergismo Farmacológico , Feminino , Genes p53 , Humanos , Membranas Intracelulares/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Naftalimidas , Proteínas de Neoplasias/metabolismo , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo , Ensaio Tumoral de Célula-Tronco , Proteína X Associada a bcl-2
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