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4.
Oncogene ; 35(48): 6189-6202, 2016 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-27157613

RESUMEN

ErbB-2 amplification/overexpression accounts for an aggressive breast cancer (BC) subtype (ErbB-2-positive). Enhanced ErbB-2 expression was also found in gastric cancer (GC) and has been correlated with poor clinical outcome. The ErbB-2-targeted therapies trastuzumab (TZ), a monoclonal antibody, and lapatinib, a tyrosine kinase inhibitor, have proved highly beneficial. However, resistance to such therapies remains a major clinical challenge. We here revealed a novel mechanism underlying the antiproliferative effects of both agents in ErbB-2-positive BC and GC. TZ and lapatinib ability to block extracellular signal-regulated kinases 1/2 and phosphatidylinositol-3 kinase (PI3K)/AKT in sensitive cells inhibits c-Myc activation, which results in upregulation of miR-16. Forced expression of miR-16 inhibited in vitro proliferation in BC and GC cells, both sensitive and resistant to TZ and lapatinib, as well as in a preclinical BC model resistant to these agents. This reveals miR-16 role as tumor suppressor in ErbB-2-positive BC and GC. Using genome-wide expression studies and miRNA target prediction algorithms, we identified cyclin J and far upstream element-binding protein 1 (FUBP1) as novel miR-16 targets, which mediate miR-16 antiproliferative effects. Supporting the clinical relevance of our results, we found that high levels of miR-16 and low or null FUBP1 expression correlate with TZ response in ErbB-2-positive primary BCs. These findings highlight a potential role of miR-16 and FUBP1 as biomarkers of sensitivity to TZ therapy. Furthermore, we revealed miR-16 as an innovative therapeutic agent for TZ- and lapatinib-resistant ErbB-2-positive BC and GC.


Asunto(s)
Neoplasias de la Mama/genética , Ciclinas/genética , ADN Helicasas/genética , Proteínas de Unión al ADN/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , MicroARNs/genética , Quinazolinas/farmacología , Neoplasias Gástricas/genética , Trastuzumab/farmacología , Regiones no Traducidas 3' , Animales , Antineoplásicos/farmacología , Sitios de Unión , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Proliferación Celular , Modelos Animales de Enfermedad , Resistencia a Antineoplásicos/genética , Femenino , Genes Supresores de Tumor , Humanos , Lapatinib , Masculino , Ratones , Modelos Biológicos , Regiones Promotoras Genéticas , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-myc/metabolismo , Interferencia de ARN , Proteínas de Unión al ARN , Receptor ErbB-2/antagonistas & inhibidores , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/metabolismo
5.
Sci Total Environ ; 556: 1-11, 2016 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-26971205

RESUMEN

Ozone (O3) is both a greenhouse gas and a secondary air pollutant causing adverse impacts on forests ecosystems at different scales, from cellular to ecosystem level. Specifically, the phytotoxic nature of O3 can impair CO2 assimilation that, in turn affects forest productivity. This study aims to evaluate the effects of tropospheric O3 on Gross Primary Production (GPP) at 37 European forest sites during the time period 2000-2010. Due to the lack of carbon assimilation data at O3 monitoring stations (and vice-versa) this study makes a first attempt to combine high resolution MODIS Gross Primary Production (GPP) estimates and O3 measurement data. Partial Correlations, Anomalies Analysis and the Random Forests Analysis (RFA) were used to quantify the effects of tropospheric O3 concentration and its uptake on GPP and to evaluate the most important factors affecting inter-annual GPP changes. Our results showed, along a North-West/South-East European transect, a negative impact of O3 on GPP ranging from 0.4% to 30%, although a key role of meteorological parameters respect to pollutant variables in affecting GPP was found. In particular, meteorological parameters, namely air temperature (T), soil water content (SWC) and relative humidity (RH) are the most important predictors at 81% of test sites. Moreover, it is interesting to highlight a key role of SWC in the Mediterranean areas (Spanish, Italian and French test sites) confirming that, soil moisture and soil water availability affect vegetation growth and photosynthesis especially in arid or semi-arid ecosystems such as the Mediterranean climate regions. Considering the pivotal role of GPP in the global carbon balance and the O3 ability to reduce primary productivity of the forests, this study can help in assessing the O3 impacts on ecosystem services, including wood production and carbon sequestration.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Monitoreo del Ambiente , Bosques , Ozono/toxicidad
6.
Oncogene ; 35(17): 2208-22, 2016 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-26212010

RESUMEN

Membrane overexpression of the receptor tyrosine kinase ErbB-2 (MErbB-2) accounts for a clinically aggressive breast cancer (BC) subtype (ErbB-2-positive) with increased incidence of metastases. We and others demonstrated that nuclear ErbB-2 (NErbB-2) also plays a key role in BC and is a poor prognostic factor in ErbB-2-positive tumors. The signal transducer and activator of transcription 3 (Stat3), another player in BC, has been recognized as a downstream mediator of MErbB-2 action in BC metastasis. Here, we revealed an unanticipated novel direction of the ErbB-2 and Stat3 interaction underlying BC metastasis. We found that Stat3 binds to its response elements (GAS) at the ErbB-2 promoter to upregulate ErbB-2 transcription in metastatic, ErbB-2-positive BC. We validated these results in several BC subtypes displaying metastatic and non-metastatic ability, highlighting Stat3 general role as upstream regulator of ErbB-2 expression in BC. Moreover, we showed that Stat3 co-opts NErbB-2 function by recruiting ErbB-2 as its coactivator at the GAS sites in the promoter of microRNA-21 (miR-21), a metastasis-promoting microRNA (miRNA). Using an ErbB-2 nuclear localization domain mutant and a constitutively activated ErbB-2 variant, we found that NErbB-2 role as a Stat3 coactivator and also its direct role as transcription factor upregulate miR-21 in BC. This reveals a novel function of NErbB-2 as a regulator of miRNAs expression. Increased levels of miR-21, in turn, downregulate the expression of the metastasis-suppressor protein programmed cell death 4 (PDCD4), a validated miR-21 target. Using an in vivo model of metastatic ErbB-2-postive BC, in which we silenced Stat3 and reconstituted ErbB-2 or miR-21 expression, we showed that both are downstream mediators of Stat3-driven metastasis. Supporting the clinical relevance of our results, we found an inverse correlation between ErbB-2/Stat3 nuclear co-expression and PDCD4 expression in ErbB-2-positive primary invasive BCs. Our findings identify Stat3 and NErbB-2 as novel therapeutic targets to inhibit ErbB-2-positive BC metastasis.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/biosíntesis , Neoplasias de la Mama/genética , MicroARNs/biosíntesis , Proteínas de Unión al ARN/biosíntesis , Receptor ErbB-2/biosíntesis , Factor de Transcripción STAT3/genética , Adolescente , Adulto , Anciano , Proteínas Reguladoras de la Apoptosis/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/genética , Persona de Mediana Edad , Metástasis de la Neoplasia , Proteínas de Unión al ARN/genética , Receptor ErbB-2/genética , Transducción de Señal , Activación Transcripcional/genética , Transfección
7.
Oncogene ; 34(26): 3413-28, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25174405

RESUMEN

Membrane overexpression of ErbB-2/HER2 receptor tyrosine kinase (membrane ErbB-2 (MErbB-2)) has a critical role in breast cancer (BC). We and others have also shown the role of nuclear ErbB-2 (NErbB-2) in BC, whose presence we identified as a poor prognostic factor in MErbB-2-positive tumors. Current anti-ErbB-2 therapies, as with the antibody trastuzumab (Ttzm), target only MErbB-2. Here, we found that blockade of NErbB-2 action abrogates growth of BC cells, sensitive and resistant to Ttzm, in a scenario in which ErbB-2, ErbB-3 and Akt are phosphorylated, and ErbB-2/ErbB-3 dimers are formed. Also, inhibition of NErbB-2 presence suppresses growth of a preclinical BC model resistant to Ttzm. We showed that at the cyclin D1 promoter, ErbB-2 assembles a transcriptional complex with Stat3 (signal transducer and activator of transcription 3) and ErbB-3, another member of the ErbB family, which reveals the first nuclear function of ErbB-2/ErbB-3 dimer. We identified NErbB-2 as the major proliferation driver in Ttzm-resistant BC, and demonstrated that Ttzm inability to disrupt the Stat3/ErbB-2/ErbB-3 complex underlies its failure to inhibit growth. Furthermore, our results in the clinic revealed that nuclear interaction between ErbB-2 and Stat3 correlates with poor overall survival in primary breast tumors. Our findings challenge the paradigm of anti-ErbB-2 drug design and highlight NErbB-2 as a novel target to overcome Ttzm resistance.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Terapia Molecular Dirigida , Proteínas Mutantes/farmacología , Receptor ErbB-2/antagonistas & inhibidores , Transporte Activo de Núcleo Celular/efectos de los fármacos , Animales , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Proliferación Celular/genética , Resistencia a Antineoplásicos/genética , Sinergismo Farmacológico , Femenino , Genes Dominantes/fisiología , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Terapia Molecular Dirigida/métodos , Proteínas Mutantes/uso terapéutico , Isoformas de Proteínas/farmacología , Isoformas de Proteínas/uso terapéutico , Transporte de Proteínas/efectos de los fármacos , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptor ErbB-2/fisiología , Trastuzumab , Células Tumorales Cultivadas
8.
Parasite Immunol ; 35(5-6): 164-73, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23473542

RESUMEN

The role of submicroscopic infections in modulating malaria antibody responses is poorly understood and requires longitudinal studies. A cohort of 249 children ≤5 years of age, 126 children between 6 and 10 years and 134 adults ≥20 years was recruited in an area of intense malaria transmission in Apac, Uganda and treated with artemether/lumefantrine at enrolment. Parasite carriage was determined at enrolment and after 6 and 16 weeks using microscopy and PCR. Antibody prevalence and titres to circumsporozoite protein, apical membrane antigen-1 (AMA-1), merozoite surface protein-1 (MSP-119 ), merozoite surface protein-2 (MSP-2) and Anopheles gambiae salivary gland protein 6 (gSG6) were determined by ELISA. Plasmodium falciparum infections were detected in 38·1% (194/509) of the individuals by microscopy and in 57·1% (284/493) of the individuals by PCR at enrolment. Antibody prevalence and titre against AMA-1, MSP-119 , MSP-2 and gSG6 were related to concurrent (sub-)microscopic parasitaemia. Responses were stable in children who were continuously infected with malaria parasites but declined in children who were never parasitaemic during the study or were not re-infected after treatment. These findings indicate that continued malaria infections are required to maintain antibody titres in an area of intense malaria transmission.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Anticuerpos/sangre , Malaria Falciparum/inmunología , Plasmodium falciparum/inmunología , Adulto , Factores de Edad , Animales , Anopheles/inmunología , Anticuerpos Antiprotozoarios/inmunología , Antígenos de Protozoos/inmunología , Niño , Preescolar , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Proteínas de Insectos/inmunología , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Malaria Falciparum/transmisión , Masculino , Parasitemia/inmunología , Prevalencia , Uganda/epidemiología , Adulto Joven
9.
Med Lav ; 100 Suppl 1: 7-10, 2009.
Artículo en Italiano | MEDLINE | ID: mdl-19848093

RESUMEN

OBJECTIVES: To assess the effectiveness of safety inspections in the construction industry in Piedmont in terms of exposure to risk and injuries. METHODS: We conducted a retrospective analysis of the surveillance activities carried out in Piedmont between 2001 and 2005: to this purpose, we used a logical framework and we identified indicators to evaluate the process and its impact on exposure and injuries. PROCESS: fixed standards involving the number of safety inspections and the type of constructions under control were respected; there was always sufficient diversity among the public works under control, although local health units used different working methods. Impact on exposure and injuries: injury rates in the construction industry in Piedmont showed a decreasing trend and systematically lower values compared to national rates. Injury rates in the "roads and railways" sector showed an increasing trend owing to the great number of public works under construction. In this case, the effect of preventive measures seems less noticeable, but this mainly depends on methodological limits, such as mismatch between numerator and denominator, difficulties in estimating the number of workers actually present on the sites, underreporting of minor events. CONCLUSIONS: Despite the limitations of a retrospective analysis, the Piedmont safety inspection programme for the construction industry showed coherence with the objectives and had a positive impact on injury rates.


Asunto(s)
Accidentes de Trabajo/prevención & control , Salud Laboral , Humanos , Italia , Estudios Retrospectivos
10.
Oncogene ; 25(59): 7723-39, 2006 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-16799639

RESUMEN

Progestin regulation of gene expression was assessed in the progestin-dependent murine tumor line C4HD which requires MPA, a synthetic progestin, for in vivo growth and expresses high levels of progesterone receptor (PR). By using suppressive subtractive hybridization, caveolin-1 was identified as a gene whose expression was increased with in vivo MPA treatment. By Northern and Western blot analysis, we further confirmed that caveolin-1 mRNA and protein expression increased in MPA-treated tumors as compared with untreated tumors. When primary cultures of C4HD cells were treated in vitro with MPA, caveolin-1 levels also increased, effect that was abolished by pre-treatment with progestin antagonist RU486. In addition, MPA promoted strong caveolin-1 promoter transcriptional activation both in mouse and human breast cancer cells. We also showed that MPA regulation of caveolin-1 expression involved in activation of two signaling pathways: MAPK and PI-3K. Short-term MPA treatment of C4HD cells led to tyrosine phosphorylation of caveolin-1 protein, where Src was the kinase involved. Additionally, we showed that MPA-induced association of caveolin-1 and PR, which was detected by coimmunoprecipitation and by confocal microscopy. Finally, we proved that MPA-induced proliferation of C4HD cells was inhibited by suppression of caveolin-1 expression with antisense oligodeoxynucleotides to caveolin-1 mRNA. Furthermore, we observed that inhibition of caveolin-1 expression abrogated PR capacity to induced luciferase activity from a progesterone response element-driven reporter plasmid. Comprehensively, our results demonstrated for the first time that caveolin-1 expression is upregulated by progestin in breast cancer. We also demonstrated that caveolin-1 is a downstream effector of MPA that is partially responsible for the stimulation of growth of breast cancer cells.


Asunto(s)
Caveolina 1/fisiología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias Mamarias Experimentales/patología , Acetato de Medroxiprogesterona/farmacología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Caveolina 1/genética , Femenino , Sistema de Señalización de MAP Quinasas , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Fosfatidilinositol 3-Quinasas/fisiología , Fosforilación , Regiones Promotoras Genéticas , Receptores de Progesterona/efectos de los fármacos , Receptores de Progesterona/fisiología , Familia-src Quinasas/fisiología
11.
Medicina (B.Aires) ; 64(2): 129-134, 2004. graf, ilus
Artículo en Español | BINACIS | ID: bin-123261

RESUMEN

We addressed the effect of targeting type I insulin-like growth factor receptor (IGF-IR), with antisense strategies in in vivo growth of breast cancer cells. We used C4HD tumors from an experimental model of hormonal carcinogenesis in which medroxyprogesterone acetate induced mammary adenocarcinomas in Balb/c mice. Intratumor or systemic administration of phosphorothiolated antisense oligodeoxynucleotides (AS[S]ODN) to IGF-IR mRNA resulted in a significant inhibition of C4HD tumor growth. The antitumor effect was specific since inhibition of tumor growth was dose-dependent and no effect was observed in mice treated with sense S[S]ODN. Tumors from AS[S]ODN-treated mice showed a decrease in IGF-IR expression and in insulin receptor substrate-1 tyrosine phosphorylation. Activation of PI-3K/Akt, p42/p44 MAPK and ErbB-2 was abolished in tumors treated with AS[S]ODN. Progesterone receptor expression or activity remained invariable. This is the first demonstration that breast cancer growth can be inhibited by direct in vivo administration of IGF-IR AS[S]ODN.(AU)


Evaluamos el efecto del bloqueo de la expresión del receptor del factor de crecimiento semejante a lainsulina tipo I (IGF-IR) sobre el crecimiento in vivo de cáncer de mama empleando una estrategia¶antisentido÷. Utilizamos el adenocarcinoma mamario murino progestágeno-dependiente C4HD. La administración intratumoral o sistémica de oligodeoxinucleótidos antisentido fosfotiolados al ARNm del IGF-IR (AS[S]ODN) inhibió el crecimiento tumoral. El efecto antitumoral fue específico debido a su dosis-dependencia y a la faltade efecto en ratones tratados con el S[S]ODN ¶sentido÷. Los tumores obtenidos de ratones tratados con AS[S]ODN mostraron: disminución en la expresión de IGF-IR y en la fosforilación del sustrato del receptor de insulina-1, inhibición de la activación de PI-3K/Akt, p42/p44MAPK y ErbB-2, mientras que la expresión y activación del receptor de progesterona no se afectó. Es la primera demostración que el(AU)


Asunto(s)
Animales , Femenino , Ratones , Adenocarcinoma/metabolismo , Neoplasias Mamarias Experimentales/metabolismo , Oligodesoxirribonucleótidos Antisentido/uso terapéutico , Receptor IGF Tipo 1/antagonistas & inhibidores , Receptores de Somatomedina/metabolismo , Adenocarcinoma/tratamiento farmacológico , Enfermedades de los Animales , Relación Dosis-Respuesta a Droga , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Medroxiprogesterona , Ratones Endogámicos BALB C , Oligodesoxirribonucleótidos Antisentido/metabolismo , ARN Mensajero/efectos de los fármacos , Receptor IGF Tipo 1/efectos de los fármacos , Receptor IGF Tipo 1/metabolismo , Células Tumorales Cultivadas
12.
Medicina (B.Aires) ; 64(2): 129-134, 2004. graf, ilus
Artículo en Español | LILACS | ID: lil-444344

RESUMEN

We addressed the effect of targeting type I insulin-like growth factor receptor (IGF-IR), with antisense strategies in in vivo growth of breast cancer cells. We used C4HD tumors from an experimental model of hormonal carcinogenesis in which medroxyprogesterone acetate induced mammary adenocarcinomas in Balb/c mice. Intratumor or systemic administration of phosphorothiolated antisense oligodeoxynucleotides (AS[S]ODN) to IGF-IR mRNA resulted in a significant inhibition of C4HD tumor growth. The antitumor effect was specific since inhibition of tumor growth was dose-dependent and no effect was observed in mice treated with sense S[S]ODN. Tumors from AS[S]ODN-treated mice showed a decrease in IGF-IR expression and in insulin receptor substrate-1 tyrosine phosphorylation. Activation of PI-3K/Akt, p42/p44 MAPK and ErbB-2 was abolished in tumors treated with AS[S]ODN. Progesterone receptor expression or activity remained invariable. This is the first demonstration that breast cancer growth can be inhibited by direct in vivo administration of IGF-IR AS[S]ODN.


Evaluamos el efecto del bloqueo de la expresión del receptor del factor de crecimiento semejante a lainsulina tipo I (IGF-IR) sobre el crecimiento in vivo de cáncer de mama empleando una estrategia“antisentido”. Utilizamos el adenocarcinoma mamario murino progestágeno-dependiente C4HD. La administración intratumoral o sistémica de oligodeoxinucleótidos antisentido fosfotiolados al ARNm del IGF-IR (AS[S]ODN) inhibió el crecimiento tumoral. El efecto antitumoral fue específico debido a su dosis-dependencia y a la faltade efecto en ratones tratados con el S[S]ODN “sentido”. Los tumores obtenidos de ratones tratados con AS[S]ODN mostraron: disminución en la expresión de IGF-IR y en la fosforilación del sustrato del receptor de insulina-1, inhibición de la activación de PI-3K/Akt, p42/p44MAPK y ErbB-2, mientras que la expresión y activación del receptor de progesterona no se afectó. Es la primera demostración que el


Asunto(s)
Animales , Femenino , Ratones , Adenocarcinoma/metabolismo , Neoplasias Mamarias Experimentales/metabolismo , Oligodesoxirribonucleótidos Antisentido , Receptor IGF Tipo 1/antagonistas & inhibidores , Receptores de Somatomedina/metabolismo , Enfermedades de los Animales , Adenocarcinoma/tratamiento farmacológico , Relación Dosis-Respuesta a Droga , Medroxiprogesterona , Ratones Endogámicos BALB C , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Oligodesoxirribonucleótidos Antisentido , ARN Mensajero/efectos de los fármacos , Receptor IGF Tipo 1/efectos de los fármacos , Receptor IGF Tipo 1/metabolismo , Células Tumorales Cultivadas
20.
Minerva Med ; 74(14-15): 835-8, 1983 Apr 07.
Artículo en Italiano | MEDLINE | ID: mdl-6340000

RESUMEN

A randomized and double blind experiment has been made over 50 patients and 25 checks, by giving a dosage of 3 Fosfolip (calcium salt of phosphorylcholine chlorid with pantethine) capsules a day. The analysis results has been reported in the work. In none case the product had secondary no desired effects; while therapeutical possibilities have been resulted in hepatosis, dyslipidosis and as energetic tonic in atherosclerotic subjects.


Asunto(s)
Colina/análogos & derivados , Panteteína/uso terapéutico , Fosforilcolina/uso terapéutico , Compuestos de Sulfhidrilo/uso terapéutico , Adulto , Anciano , Arteriosclerosis/sangre , Arteriosclerosis/tratamiento farmacológico , Ensayos Clínicos como Asunto , Método Doble Ciego , Combinación de Medicamentos/uso terapéutico , Femenino , Humanos , Hiperlipidemias/sangre , Hiperlipidemias/tratamiento farmacológico , Lípidos/sangre , Hepatopatías/sangre , Hepatopatías/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Panteteína/análogos & derivados
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