Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
Rev. bras. ciênc. esporte ; 43: e007221, 2021. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1351688

RESUMEN

ABSTRACT Penalty kicks are often decisive in football matches. Therefore, any technique that yields an advantage either in scoring or saving them is of great importance. Here we show the influence of a training programme for goalkeepers on the probability of defending penalties in men's football. Virtual training was used through an app that shows the shooter at the moment of setting the support foot on the ground and requiring the answer of which side (right or left) the ball will be directed at. Complemented with physical training, four sub 21 professional goalkeepers from Santarém, Brazil, developed the ability to correctly choose the side (left or right) at which the ball will be aimed. Sets of 800 penalties were kicked before (acting as control group) and after the training programme and it was found that, after training, the chances of saving penalty kicks or, at least, choosing the correct side, increase dramatically. It is concluded that the training programme improved the goalkeeper's ability to choose the correct side. Other factors (laterality and height) were not found to be statistically significant.


RESUMO Os pênaltis são frequentemente decisivos em partidas de futebol. Portanto, qualquer técnica que produza uma vantagem tanto para marcar como para salvá-los é de grande importância. Aqui mostramos a influência de um programa de treinamento de goleiros na probabilidade de defesa de pênaltis no futebol masculino. O treinamento virtual foi utilizado por meio de um aplicativo que mostra o chutador no momento de colocar o pé de apoio no solo e exigir a resposta de qual lado (direito ou esquerdo) a bola será direcionada. Complementado com treinamento físico, quatro goleiros profissionais sub 21 de Santarém, Brasil, desenvolveram a habilidade de escolher corretamente o lado (esquerdo ou direito) para o qual a bola seria direcionada. Conjuntos de 800 pênaltis foram chutados antes (agindo como um grupo de controle) e depois do programa de treinamento e verificou-se que, após o treino, as chances de salvar pênaltis ou, pelo menos, de escolher o lado correto aumentam drasticamente. Conclui-se que o programa de treinamento melhorou a habilidade do goleiro em escolher o lado correto. Outros fatores (lateralidade e estatura) não mostraram ser estadísticamente significativos.


RESUMEN Los tiros penales suelen ser decisivos en los partidos de fútbol. Por lo tanto, cualquier técnica que proporcione una ventaja, ya sea para anotar o para atajarlos, es de gran importancia. Aquí mostramos la influencia de un programa de entrenamiento para goleros sobre la probabilidad de atajar los penaltis en el fútbol masculino. Se utilizó entrenamiento virtual a través de una aplicación que muestra al tirador en el momento de poner el pie de apoyo en el suelo y que requiere la respuesta de hacia qué lado (derecho o izquierdo) se dirigirá el balón. Complementado con entrenamiento físico, cuatro goleros profesionales sub 21 de Santarém, Brasil, desarrollaron la capacidad de elegir correctamente el lado (izquierdo o derecho) al que se dirigiría el balón. Se lanzaron series de 800 penales antes (actuando como un grupo de control) y después del programa de entrenamiento y se encontró que, después del entrenamiento, las posibilidades de atajarlos o, al menos, elegir el lado correcto, aumentan drásticamente. Se concluye que el programa de entrenamiento mejoró la capacidad del golero para elegir el lado correcto. Otros factores (lateralidad y estatura) no mostraron ser estadísticamente significativos.

2.
Clin Cancer Res ; 24(24): 6396-6407, 2018 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-30171047

RESUMEN

PURPOSE: STA-1474, prodrug of the heat shock protein 90 inhibitor (HSP90i) ganetespib, previously demonstrated activity in canine preclinical models of cancer; interestingly, prolonged infusions were associated with improved biologic activity. The purpose of this study was to identify the ideal treatment schedule for HSP90i in preclinical models of KIT-driven malignancies and in dogs with spontaneous mast cell tumors (MCT), where KIT is a known driver. EXPERIMENTAL DESIGN: In vitro and murine xenograft experiments and clinical studies in dogs with MCTs were used to define the effects of HSP90i-dosing regimen on client protein downregulation and antitumor activity. RESULTS: Continuous HSP90 inhibition led to durable destabilization of client proteins in vitro; however, transient exposure required >10× drug for comparable effects. In vivo, KIT was rapidly degraded following a single dose of HSP90i but returned to baseline levels within a day. HSP90 levels increased and stabilized 16 hours after HSP90i and were not elevated following a subsequent near-term exposure, providing a functional pool of chaperone to stabilize proteins and a means for greater therapeutic activity upon HSP90i reexposure. HSP90i administered on days 1 and 2 (D1/D2) demonstrated increased biologic activity compared with D1 treatment in KIT or EGFR-driven murine tumor models. In a trial of dogs with MCT, D1/D2 dosing of HSP90i was associated with sustained KIT downregulation, 50% objective response rate and 100% clinical benefit rate compared with D1 and D1/D4 schedules. CONCLUSIONS: These data provide further evidence that prolonged HSP90i exposure improves biologic activity through sustained downregulation of client proteins.


Asunto(s)
Antineoplásicos/farmacología , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Leucemia de Mastocitos/etiología , Leucemia de Mastocitos/metabolismo , Proteínas Proto-Oncogénicas c-kit/metabolismo , Animales , Línea Celular Tumoral , Modelos Animales de Enfermedad , Perros , Proteínas HSP90 de Choque Térmico/genética , Proteínas HSP90 de Choque Térmico/metabolismo , Leucemia de Mastocitos/tratamiento farmacológico , Leucemia de Mastocitos/patología , Ratones , Oncogenes , Proteolisis , Proteínas Proto-Oncogénicas c-kit/genética , Resultado del Tratamiento , Triazoles/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto
3.
Mol Cancer Ther ; 14(11): 2422-32, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26271675

RESUMEN

The clinical benefits of chemotherapy are commonly offset by insufficient drug exposures, narrow safety margins, and/or systemic toxicities. Over recent decades, a number of conjugate-based targeting approaches designed to overcome these limitations have been explored. Here, we report on an innovative strategy that utilizes HSP90 inhibitor-drug conjugates (HDC) for directed tumor targeting of chemotherapeutic agents. STA-12-8666 is an HDC that comprises an HSP90 inhibitor fused to SN-38, the active metabolite of irinotecan. Mechanistic analyses in vitro established that high-affinity HSP90 binding conferred by the inhibitor backbone could be exploited for conjugate accumulation within tumor cells. In vivo modeling showed that the HSP90 inhibitor moiety was required for selective retention of STA-12-8666, and this enrichment promoted extended release of active SN-38 within the tumor compartment. Indeed, controlled intratumoral payload release by STA-12-8666 contributed to a broad therapeutic window, sustained biomarker activity, and remarkable degree of efficacy and durability of response in multiple cell line and patient-derived xenograft models. Overall, STA-12-8666 has been developed as a unique HDC agent that employs a distinct mechanism of targeted drug delivery to achieve potent and sustained antitumor effects. These findings identify STA-12-8666 as a promising new candidate for evaluation as novel anticancer therapeutic.


Asunto(s)
Antineoplásicos/farmacología , Camptotecina/análogos & derivados , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Resorcinoles/farmacología , Triazoles/farmacología , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Western Blotting , Camptotecina/química , Camptotecina/farmacocinética , Camptotecina/farmacología , Línea Celular Tumoral , Femenino , Proteínas HSP90 de Choque Térmico/metabolismo , Humanos , Irinotecán , Ratones Endogámicos ICR , Ratones SCID , Microscopía Fluorescente , Terapia Molecular Dirigida/métodos , Neoplasias/metabolismo , Neoplasias/patología , Resorcinoles/química , Resorcinoles/farmacocinética , Inhibidores de Topoisomerasa I/administración & dosificación , Inhibidores de Topoisomerasa I/farmacocinética , Inhibidores de Topoisomerasa I/farmacología , Resultado del Tratamiento , Triazoles/administración & dosificación , Triazoles/farmacocinética , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
4.
Target Oncol ; 10(2): 235-45, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25077897

RESUMEN

Small molecule inhibitors of epidermal growth factor receptor (EGFR) tyrosine kinase activity, such as erlotinib and gefitinib, revolutionized therapy for non-small cell lung cancer (NSCLC) patients whose tumors harbor activating EGFR mutations. However, mechanisms to overcome the invariable development of acquired resistance to such agents, as well as realizing their full clinical potential within the context of wild-type EGFR (WT-EGFR) disease, remain to be established. Here, the antitumor efficacy of targeted EGFR tyrosine kinase inhibitors (TKIs) and the HSP90 inhibitor ganetespib, alone and in combination, were evaluated in NSCLC. Ganetespib potentiated the efficacy of erlotinib in TKI-sensitive, mutant EGFR-driven NCI-HCC827 xenograft tumors, with combination treatment causing significant tumor regressions. In erlotinib-resistant NCI-H1975 xenografts, concurrent administration of ganetespib overcame erlotinib resistance to significantly improve tumor growth inhibition. Ganetespib co-treatment also significantly enhanced antitumor responses to afatinib in the same model. In WT-EGFR cell lines, ganetespib potently reduced cell viability. In NCI-H1666 cells, ganetespib-induced loss of client protein expression, perturbation of oncogenic signaling pathways, and induction of apoptosis translated to robust single-agent activity in vivo. Dual ganetespib/erlotinib therapy induced regressions in NCI-H322 xenograft tumors, indicating that the sensitizing properties of ganetespib for erlotinib were conserved within the WT-EGFR setting. Mechanistically, combined ganetespib/erlotinib exposure stabilized EGFR protein levels in an inactive state and completely abrogated extracellular-signal-regulated kinase (ERK) and AKT signaling activity. Thus, selective HSP90 blockade by ganetespib represents a potentially important complementary strategy to targeted TKI inhibition alone for inducing substantial antitumor responses and overcoming resistance, in both the mutant and WT-EGFR settings.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Receptores ErbB/antagonistas & inhibidores , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Neoplasias Pulmonares/tratamiento farmacológico , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Triazoles/farmacología , Animales , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Resistencia a Antineoplásicos , Sinergismo Farmacológico , Receptores ErbB/genética , Receptores ErbB/metabolismo , Femenino , Proteínas HSP90 de Choque Térmico/metabolismo , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Ratones SCID , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Mol Cancer Res ; 12(7): 1042-54, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24784839

RESUMEN

UNLABELLED: Activating mutations and/or overexpression of FGFR3 are common in bladder cancer, making FGFR3 an attractive therapeutic target in this disease. In addition, FGFR3 gene rearrangements have recently been described that define a unique subset of bladder tumors. Here, a selective HSP90 inhibitor, ganetespib, induced loss of FGFR3-TACC3 fusion protein expression and depletion of multiple oncogenic signaling proteins in RT112 bladder cells, resulting in potent cytotoxicity comparable with the pan-FGFR tyrosine kinase inhibitor BGJ398. However, in contrast to BGJ398, ganetespib exerted pleiotropic effects on additional mitogenic and survival pathways and could overcome the FGFR inhibitor-resistant phenotype of FGFR3 mutant-expressing 97-7 and MHG-U3 cells. Combinatorial benefit was observed when ganetespib was used with BGJ398 both in vitro and in vivo. Interestingly, two additional FGFR3 fusion-positive lines (RT4 and SW480) retained sensitivity to HSP90 inhibitor treatment by the ansamycins 17-AAG and 17-DMAG yet displayed intrinsic resistance to ganetespib or AUY922, both second-generation resorcinol-based compounds. Both cell lines, compared with RT112, expressed considerably higher levels of endogenous UGT1A enzyme; this phenotype resulted in a rapid glucuronidation-dependent metabolism and subsequent efflux of ganetespib from SW780 cells, thus providing a mechanism to account for the lack of bioactivity. IMPLICATIONS: Pharmacologic blockade of the molecular chaperone HSP90 represents a promising approach for treating bladder tumors driven by oncogenic gene rearrangements of FGFR3. Furthermore, UDP-glucuronosyltransferase enzyme expression may serve as a predictive factor for clinical response to resorcinol-based HSP90 inhibitors.


Asunto(s)
Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/antagonistas & inhibidores , Triazoles/farmacología , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/metabolismo , Animales , Línea Celular Tumoral , Femenino , Proteínas HSP90 de Choque Térmico/genética , Proteínas HSP90 de Choque Térmico/metabolismo , Humanos , Ratones , Ratones Desnudos , Terapia Molecular Dirigida , Distribución Aleatoria , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/genética , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/metabolismo , Transducción de Señal , Triazoles/farmacocinética , Neoplasias de la Vejiga Urinaria/genética , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Invest New Drugs ; 32(4): 577-86, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24682747

RESUMEN

The integration of targeted agents to standard cytotoxic regimens has improved outcomes for patients with colorectal cancer (CRC) over recent years; however this malignancy remains the second leading cause of cancer mortality in industrialized countries. Small molecule inhibitors of heat shock protein 90 (HSP90) are one of the most actively pursued classes of compounds for the development of new cancer therapies. Here we evaluated the activity of ganetespib, a second-generation HSP90 inhibitor, in models of CRC. Ganetespib reduced cell viability in a panel of CRC cell lines in vitro with low nanomolar potency. Mechanistically, drug treatment exerted concomitant effects on multiple oncogenic signaling pathways, cell cycle regulation, and DNA damage repair capacity to promote apoptosis. Combinations of ganetespib and low-dose ionizing radiation enhanced the radiosensitivity of HCT 116 cells and resulted in superior cytotoxic activity over either treatment alone. In vivo, the single-agent activity of ganetespib was relatively modest, suppressing HCT 116 xenograft tumor growth by approximately half. However, ganetespib significantly potentiated the antitumor efficacy of the 5-Fluorouracil (5-FU) prodrug capecitabine in HCT 116 xenografts, causing tumor regressions in a model that is intrinsically resistant to fluoropyrimidine therapy. This demonstration of combinatorial benefit afforded by an HSP90 inhibitor to a standard CRC adjuvant regimen provides an attractive new framework for the potential application of ganetespib as an investigational agent in this disease.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Fármacos Sensibilizantes a Radiaciones/farmacología , Triazoles/farmacología , Animales , Apoptosis/efectos de los fármacos , Capecitabina , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Quimioterapia Adyuvante/métodos , Neoplasias Colorrectales/radioterapia , Daño del ADN/efectos de los fármacos , Reparación del ADN/efectos de los fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Femenino , Fluorouracilo/análogos & derivados , Fluorouracilo/farmacología , Células HCT116 , Humanos , Ratones , Ratones Desnudos , Radiación Ionizante , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Mol Cancer Res ; 12(5): 703-13, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24554781

RESUMEN

UNLABELLED: Because of their pleiotropic effects on critical oncoproteins, inhibitors of HSP90 represent a promising new class of therapeutic agents for the treatment of human cancer. However, pharmacologic inactivation of HSP90 subsequently triggers a heat shock response that may mitigate the full therapeutic benefit of these compounds. To overcome this limitation, a clinically feasible method was sought to block HSP synthesis induced by the potent HSP90 inhibitor ganetespib. An immunoassay screen of 322 late-stage or clinically approved drugs was performed to uncover compounds that could block upregulation of the stress-inducible HSP70 that results as a consequence of HSP90 blockade. Interestingly, inhibitors of the phosphoinositide 3-kinase (PI3K)/mTOR class counteracted ganetespib-induced HSP70 upregulation at both the gene and protein level by suppressing nuclear translocation of heat shock factor 1 (HSF1), the dominant transcription factor controlling cellular stress responses. This effect was conserved across multiple tumor types and was found to be regulated, in part, by mTOR-dependent translational activity. Pretreatment with cycloheximide, PI3K/mTOR inhibitor, or an inhibitor of eIF4E (a translation initiation factor and downstream effector of mTOR) all reduced ganetespib-mediated nuclear HSF1 accumulation, indicating that mTOR blockade confers a negative regulatory effect on HSF1 activity. Moreover, combined therapy regimens with mTOR or dual PI3K/mTOR inhibitors potentiated the antitumor efficacy of ganetespib in multiple in vivo models. IMPLICATIONS: Collectively these data identify a novel strategy to optimize the therapeutic potential of HSP90 inhibitors.


Asunto(s)
Antineoplásicos/farmacología , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Animales , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Línea Celular Tumoral , Femenino , Proteínas HSP70 de Choque Térmico/metabolismo , Proteínas HSP90 de Choque Térmico/metabolismo , Respuesta al Choque Térmico/efectos de los fármacos , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Masculino , Ratones , Ratones SCID , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Distribución Aleatoria , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Triazoles/farmacología , Regulación hacia Arriba/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
8.
Mol Cancer Ther ; 13(2): 353-63, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24398428

RESUMEN

Activating BRAF kinase mutations serve as oncogenic drivers in over half of all melanomas, a feature that has been exploited in the development of new molecularly targeted approaches to treat this disease. Selective BRAF(V600E) inhibitors, such as vemurafenib, typically induce initial, profound tumor regressions within this group of patients; however, durable responses have been hampered by the emergence of drug resistance. Here, we examined the activity of ganetespib, a small-molecule inhibitor of Hsp90, in melanoma lines harboring the BRAF(V600E) mutation. Ganetespib exposure resulted in the loss of mutant BRAF expression and depletion of mitogen-activated protein kinase and AKT signaling, resulting in greater in vitro potency and antitumor efficacy compared with targeted BRAF and MAP-ERK kinase (MEK) inhibitors. Dual targeting of Hsp90 and BRAF(V600E) provided combinatorial benefit in vemurafenib-sensitive melanoma cells in vitro and in vivo. Importantly, ganetespib overcame mechanisms of intrinsic and acquired resistance to vemurafenib, the latter of which was characterized by reactivation of extracellular signal-regulated kinase (ERK) signaling. Continued suppression of BRAF(V600E) by vemurafenib potentiated sensitivity to MEK inhibitors after acquired resistance had been established. Ganetespib treatment reduced, but not abolished, elevations in steady-state ERK activity. Profiling studies revealed that the addition of a MEK inhibitor could completely abrogate ERK reactivation in the resistant phenotype, with ganetespib displaying superior combinatorial activity over vemurafenib. Moreover, ganetespib plus the MEK inhibitor TAK-733 induced tumor regressions in vemurafenib-resistant xenografts. Overall these data highlight the potential of ganetespib as a single-agent or combination treatment in BRAF(V600E)-driven melanoma, particularly as a strategy to overcome acquired resistance to selective BRAF inhibitors.


Asunto(s)
Resistencia a Antineoplásicos/efectos de los fármacos , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Indoles/farmacología , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Sulfonamidas/farmacología , Triazoles/farmacología , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bencimidazoles/administración & dosificación , Bencimidazoles/farmacología , Western Blotting , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Células Cultivadas , Resistencia a Antineoplásicos/genética , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Proteínas HSP90 de Choque Térmico/metabolismo , Humanos , Melanoma/tratamiento farmacológico , Melanoma/genética , Melanoma/metabolismo , Ratones Desnudos , Ratones SCID , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Mutación , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Piridonas/administración & dosificación , Piridonas/farmacología , Pirimidinonas/administración & dosificación , Pirimidinonas/farmacología , Triazoles/administración & dosificación , Vemurafenib , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Clin Cancer Res ; 20(2): 413-24, 2014 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-24173541

RESUMEN

PURPOSE: Treatment options for patients with triple-negative breast cancer (TNBC) are largely limited to systemic chemotherapies, which have shown disappointing efficacy in the metastatic setting. Here, we undertook a comprehensive evaluation of the activity of ganetespib, a potent inhibitor of HSP90, in this malignancy. EXPERIMENTAL DESIGN: The antitumor and antimetastatic activity of ganetespib was investigated using TNBC cell lines and xenograft models. Combinatorial drug analyses were performed with chemotherapeutic agents and concomitant effects on DNA damage and cell-cycle disruption were assessed in vitro; antitumor efficacy was assessed in vivo. Metabolic and objective tumor responses were evaluated in patients with metastatic TNBC undergoing ganetespib treatment. RESULTS: Ganetespib simultaneously deactivated multiple oncogenic pathways to potently reduce cell viability in TNBC cell lines, and suppressed lung metastases in experimental models. Ganetespib potentiated the cytotoxic activity of doxorubicin via enhanced DNA damage and mitotic arrest, conferring superior efficacy to the doxorubicin-cyclophosphamide regimen in TNBC xenografts. Ganetespib also promoted mitotic catastrophe and apoptosis in combination with taxanes in vitro, and these effects translated to significantly improved combinatorial activity in vivo. Marked tumor shrinkage of metastatic lung and lymphatic lesions were seen in patients on ganetespib monotherapy. CONCLUSION: The preclinical activity profile and clinical evidence of tumor regression suggest that ganetespib offers considerable promise as a new therapeutic candidate to target TNBC.


Asunto(s)
Antineoplásicos/farmacología , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Triazoles/farmacología , Neoplasias de la Mama Triple Negativas/metabolismo , Animales , Antineoplásicos/uso terapéutico , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Resistencia a Antineoplásicos , Sinergismo Farmacológico , Femenino , Proteínas HSP90 de Choque Térmico/metabolismo , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/secundario , Ratones , Mitosis/efectos de los fármacos , Metástasis de la Neoplasia , Estadificación de Neoplasias , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Triazoles/uso terapéutico , Neoplasias de la Mama Triple Negativas/diagnóstico , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Ensayos Antitumor por Modelo de Xenoinjerto
10.
Cancer Discov ; 3(4): 430-43, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23533265

RESUMEN

UNLABELLED: EML4-ALK gene rearrangements define a unique subset of patients with non-small cell lung carcinoma (NSCLC), and the clinical success of the anaplastic lymphoma kinase (ALK) inhibitor crizotinib in this population has become a paradigm for molecularly targeted therapy. Here, we show that the Hsp90 inhibitor ganetespib induced loss of EML4-ALK expression and depletion of multiple oncogenic signaling proteins in ALK-driven NSCLC cells, leading to greater in vitro potency, superior antitumor efficacy, and prolonged animal survival compared with results obtained with crizotinib. In addition, combinatorial benefit was seen when ganetespib was used with other targeted ALK agents both in vitro and in vivo. Importantly, ganetespib overcame multiple forms of crizotinib resistance, including secondary ALK mutations, consistent with activity seen in a patient with crizotinib-resistant NSCLC. Cancer cells driven by ALK amplification and oncogenic rearrangements of ROS1 and RET kinase genes were also sensitive to ganetespib exposure. Taken together, these results highlight the therapeutic potential of ganetespib for ALK-driven NSCLC. SIGNIFICANCE: In addition to direct kinase inhibition, pharmacologic blockade of the molecular chaperone Hsp90 is emerging as a promising approach for treating tumors driven by oncogenic rearrangements of ALK. The bioactivity profi le of ganetespib presented here underscores a new therapeutic opportunity to target ALK and overcome multiple mechanisms of resistance in patients with ALK-positive NSCLC.


Asunto(s)
Antineoplásicos/administración & dosificación , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Neoplasias Pulmonares/tratamiento farmacológico , Proteínas Tirosina Quinasas Receptoras/genética , Triazoles/administración & dosificación , Adulto , Quinasa de Linfoma Anaplásico , Animales , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Crizotinib , Resistencia a Antineoplásicos , Femenino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Masculino , Ratones , Ratones Desnudos , Ratones SCID , Pirazoles/administración & dosificación , Piridinas/administración & dosificación , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Adulto Joven
11.
Int J Oncol ; 42(1): 35-43, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23152004

RESUMEN

Androgen ablation therapy represents the first line of therapeutic intervention in men with advanced or recurrent prostate tumors. However, the incomplete efficacy and lack of durable response to this clinical strategy highlights an urgent need for alternative treatment options to improve patient outcomes. Targeting the molecular chaperone heat shock protein 90 (Hsp90) represents a potential avenue for therapeutic intervention as its inhibition results in the coordinate blockade of multiple oncogenic signaling pathways in cancer cells. Moreover, Hsp90 is essential for the stability and function of numerous client proteins, a number of which have been causally implicated in the pathogenesis of prostate cancer, including the androgen receptor (AR). Here, we examined the preclinical activity of ganetespib, a small molecule inhibitor of Hsp90, in a panel of prostate cancer cell lines. Ganetespib potently decreased viability in all lines, irrespective of their androgen sensitivity or receptor status, and more effectively than the ansamycin inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG). Interestingly, while ganetespib exposure decreased AR expression and activation, the constitutively active V7 truncated isoform of the receptor was unaffected by Hsp90 inhibition. Mechanistically, ganetespib exerted concomitant effects on mitogenic and survival pathways, as well as direct modulation of cell cycle regulators, to induce growth arrest and apoptosis. Further, ganetespib displayed robust antitumor efficacy in both AR-negative and positive xenografts, including those derived from the 22Rv1 prostate cancer cell line that co-expresses full-length and variant receptors. Together these data suggest that further investigation of ganetespib as a new therapeutic treatment for prostate cancer patients is warranted.


Asunto(s)
Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Neoplasias de la Próstata/patología , Triazoles/farmacología , Animales , Benzoquinonas/farmacología , Western Blotting , Ciclo Celular/efectos de los fármacos , Proteínas de Ciclo Celular/metabolismo , Citometría de Flujo , Proteínas HSP90 de Choque Térmico/metabolismo , Humanos , Lactamas Macrocíclicas/farmacología , Masculino , Ratones , Ratones SCID , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Androgénicos/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Mol Cancer Ther ; 11(12): 2633-43, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23012248

RESUMEN

Mutant KRAS is a feature of more than 25% of non-small cell lung cancers (NSCLC) and represents one of the most prevalent oncogenic drivers in this disease. NSCLC tumors with oncogenic KRAS respond poorly to current therapies, necessitating the pursuit of new treatment strategies. Targeted inhibition of the molecular chaperone Hsp90 results in the coordinated blockade of multiple oncogenic signaling pathways in tumor cells and has thus emerged as an attractive avenue for therapeutic intervention in human malignancies. Here, we examined the activity of ganetespib, a small-molecule inhibitor of Hsp90 currently in clinical trials for NSCLCs in a panel of lung cancer cell lines harboring a diverse spectrum of KRAS mutations. In vitro, ganetespib was potently cytotoxic in all lines, with concomitant destabilization of KRAS signaling effectors. Combinations of low-dose ganetespib with MEK or PI3K/mTOR inhibitors resulted in superior cytotoxic activity than single agents alone in a subset of mutant KRAS cells, and the antitumor efficacy of ganetespib was potentiated by cotreatment with the PI3K/mTOR inhibitor BEZ235 in A549 xenografts in vivo. At the molecular level, ganetespib suppressed activating feedback signaling loops that occurred in response to MEK and PI3K/mTOR inhibition, although this activity was not the sole determinant of combinatorial benefit. In addition, ganetespib sensitized mutant KRAS NSCLC cells to standard-of-care chemotherapeutics of the antimitotic, topoisomerase inhibitor, and alkylating agent classes. Taken together, these data underscore the promise of ganetespib as a single-agent or combination treatment in KRAS-driven lung tumors.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Genes ras , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Mutación , Triazoles/farmacología , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Bencimidazoles/administración & dosificación , Bencimidazoles/farmacología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Femenino , Humanos , Imidazoles/administración & dosificación , Imidazoles/farmacología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Ratones , Ratones Desnudos , Inhibidores de las Quinasa Fosfoinosítidos-3 , Quinolinas/administración & dosificación , Quinolinas/farmacología , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Triazoles/administración & dosificación , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Invest New Drugs ; 30(6): 2201-9, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22227828

RESUMEN

Systemic chemotherapy using two-drug platinum-based regimens for the treatment of advanced stage non-small cell lung cancer (NSCLC) has largely reached a plateau of effectiveness. Accordingly, efforts to improve survival and quality of life outcomes have more recently focused on the use of molecularly targeted agents, either alone or in combination with standard of care therapies such as taxanes. The molecular chaperone heat shock protein 90 (Hsp90) represents an attractive candidate for therapeutic intervention, as its inhibition results in the simultaneous blockade of multiple oncogenic signaling cascades. Ganetespib is a non-ansamycin inhibitor of Hsp90 currently under clinical evaluation in a number of human malignancies, including NSCLC. Here we show that ganetespib potentiates the cytotoxic activity of the taxanes paclitaxel and docetaxel in NSCLC models. The combination of ganetespib with paclitaxel, docetaxel or another microtubule-targeted agent vincristine resulted in synergistic antiproliferative effects in the H1975 cell line in vitro. These benefits translated to improved efficacy in H1975 xenografts in vivo, with significantly enhanced tumor growth inhibition observed in combination with paclitaxel and tumor regressions seen with docetaxel. Notably, concurrent exposure to ganetespib and docetaxel improved antitumor activity in 5 of 6 NSCLC xenograft models examined. Our data suggest that the improved therapeutic indices are likely to be mechanistically multifactorial, including loss of pro-survival signaling and direct cell cycle effects resulting from Hsp90 modulation by ganetespib. Taken together, these findings provide preclinical evidence for the use of this combination to treat patients with advanced NSCLC.


Asunto(s)
Antineoplásicos/administración & dosificación , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Paclitaxel/administración & dosificación , Taxoides/administración & dosificación , Triazoles/administración & dosificación , Animales , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Docetaxel , Combinación de Medicamentos , Femenino , Humanos , Ratones , Ratones SCID , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Cienc. cogn ; 15(3): 13-22, dez. 20, 2010.
Artículo en Portugués | Index Psicología - Revistas | ID: psi-58839

RESUMEN

Este estudo teve como objetivo demonstrar o valor de um programa de estimulação cortical, voltado para o déficit de atenção de alunos com Síndrome de Down, de ambos os sexos e idade compreendida entre 17 e 21 anos. A metodologia de trabalho foi desenvolvida por meio de pesquisa experimental, e a estratégia metodológica adotada foi a realização de um pré-teste e um pós-teste de processamento mental, que avaliou o tempo de reação a um estímulo programado. Entre esses testes, realizou-se a intervenção que ocorreu durante um mês, por meio de 20 sessões de estimulação cortical, sendo uma sessão por dia com duração de 40 minutos. Os resultados mostraram uma melhora significativa no tempo de reação (p = 0.0207), confirmando que a referida estimulação atua positivamente, ou de forma valiosa, no estado de atenção e de concentração prolongada de indivíduos com síndrome de Down


Asunto(s)
Tiempo de Reacción , Educación de las Personas con Discapacidad Intelectual , Síndrome de Down
15.
Ciênc. cogn ; 15(3): 13-22, 2010.
Artículo en Portugués | LILACS, Index Psicología - Revistas | ID: lil-700323

RESUMEN

Este estudo teve como objetivo demonstrar o valor de um programa de estimulação cortical, voltado para o déficit de atenção de alunos com Síndrome de Down, de ambos os sexos e idade compreendida entre 17 e 21 anos. A metodologia de trabalho foi desenvolvida por meio de pesquisa experimental, e a estratégia metodológica adotada foi a realização de um pré-teste e um pós-teste de processamento mental, que avaliou o tempo de reação a um estímulo programado. Entre esses testes, realizou-se a intervenção que ocorreu durante um mês, por meio de 20 sessões de estimulação cortical, sendo uma sessão por dia com duração de 40 minutos. Os resultados mostraram uma melhora significativa no tempo de reação (p = 0.0207), confirmando que a referida estimulação atua positivamente, ou de forma valiosa, no estado de atenção e de concentração prolongada de indivíduos com síndrome de Down.


Asunto(s)
Educación de las Personas con Discapacidad Intelectual , Tiempo de Reacción , Síndrome de Down
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...