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Des R Richardson - One of the best experts on this subject based on the ideXlab platform.
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the iron chelator deferasirox as a novel strategy for cancer treatment oral activity against human lung tumor xenografts and molecular mechanism of action
Molecular Pharmacology, 2013Co-Authors: Goldie Y L Lui, Peyman Obeidy, Samuel J Ford, Chris Tselepis, Danae M Sharp, Patric J Jansson, Danuta S Kalinowski, Zaklina Kovacevic, David B Lovejoy, Des R RichardsonAbstract:Deferasirox is an orally effective iron (Fe) chelator currently used for the treatment of iron-overload disease and has been implemented as an alternative to the gold standard chelator, desferrioxamine (DFO). Earlier studies demonstrated that DFO exhibits anticancer activity due to its ability to deplete cancer cells of iron. In this investigation, we examined the in vitro and in vivo activity of deferasirox against cells from human solid tumors. To date, there have been no studies to investigate the effect of deferasirox on these types of tumors in vivo. Deferasirox demonstrated similar activity at inhibiting proliferation of DMS-53 lung carcinoma and SK-N-MC Neuroepithelioma cell lines compared with DFO. Furthermore, deferasirox was generally similar or slightly more effective than DFO at mobilizing cellular 59Fe and inhibiting iron uptake from human transferrin depending on the cell type. However, deferasirox potently inhibited DMS-53 xenograft growth in nude mice when given by oral gavage, with no marked alterations in normal tissue histology. To understand the antitumor activity of deferasirox, we investigated its effect on the expression of molecules that play key roles in metastasis, cell cycle control, and apoptosis. We demonstrated that deferasirox increased expression of the metastasis suppressor protein N -myc downstream-regulated gene 1 and upregulated the cyclin-dependent kinase inhibitor p21CIP1/WAF1 while decreasing cyclin D1 levels. Moreover, this agent increased the expression of apoptosis markers, including cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase 1. Collectively, we demonstrate that deferasirox is an orally effective antitumor agent against solid tumors.
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novel di 2 pyridyl derived iron chelators with marked and selective antitumor activity in vitro and in vivo assessment
Blood, 2004Co-Authors: Jun Yuan, David B Lovejoy, Des R RichardsonAbstract:Aroylhydrazone and thiosemicarbazone iron (Fe) chelators have potent antitumor activity. The aim of the current study was to examine the antitumor effects and mechanisms of action of a novel series of Fe chelators, the di-2-pyridyl thiosemicarbazones. Of 7 new chelators synthesized, 4 showed pronounced antiproliferative effects. The most active chelator was Dp44mT, which had marked and selective antitumor activity—for example, an IC50 of 0.03 μM in Neuroepithelioma cells compared with more than 25 μM in mortal fibroblasts. Indeed, this antiproliferative activity was the greatest yet observed for an Fe chelator. Efficacy was greater than it was for the cytotoxic ligand 311 and comparable to that of the antitumor agent doxorubicin. Strikingly, Dp44mT significantly ( P < .01) decreased tumor weight in mice to 47% of the weight in the control after only 5 days, whereas there was no marked change in animal weight or hematologic indices. Terminal deoxyribonucleotidyl transferase (TdT)–mediated dUTP nick end-labeling (TUNEL) staining demonstrated apoptosis in tumors taken from mice treated with Dp44mT. This chelator caused a marked increase of caspase-3 activity in murine Madison-109 (M109) cells. Caspase activation was at least partially mediated by the release of mitochondrial holo-cytochrome c (h-cytc) after incubation with Dp44mT. In conclusion, Dp44mT is a novel, highly effective antitumor agent in vitro and in vivo that induces apoptosis.
Adrados M. - One of the best experts on this subject based on the ideXlab platform.
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Tumores neuroectodérmicos primitivos periféricos de localización en el área orocervical: presentación de dos casos clínicos
SECOM. Published by Elsevier España S.L., 2010Co-Authors: Sánchez Acedo C., Muñoz Guerra M.f., Naval Gías L., Martos P.l., Adrados M.Abstract:ResumenIntroducción: Los tumores neuroectodérmicos primitivos (PNET, de primitive neuroectodermal tumors) son una familia de neoplasias malignas de células pequeñas y redondas, que derivan de la cresta neural. Se distinguen tres tipos: PNET del sistema nervioso central, PNET del sistema nervioso autónomo y PNET periféricos. Los más frecuentes dentro del grupo de PNET periféricos son el neuroepitelioma periférico y el sarcoma de Ewing, que se consideran la misma neoplasia pero con diferente grado de diferenciación. Casos clínicos: Presentamos dos casos de PNET periféricos, uno de aparición en la región cervical y otro originado en el cóndilo mandibular.Discusión: Los PNET son neoplasias muy raras y altamente agresivas. En todos ellos aparecen células redondas pequeñas poco diferenciadas y una traslocación cromosómica característica del gen EWS. En general se considera que tienen un pronóstico desfavorable. Además, la baja frecuencia de estos tumores, así como la escasez de casos publicados hacen difícil valorar el tratamiento más adecuado.AbstractIntroduction: Peripheral primitive neuroectodermal tumors (PNET) are a family of smallround cell tumors of presumed neuroectodermal origin. This broad family can be subdivided into three major groups: PNET from the central nervous system, PNET from the autonomic nervous system or peripheral PNET. Ewing's sarcoma and peripheral neuroepitelioma, the two most frequently encountered members of the peripheral PNET family, are considered to represent a spectrum according to the extent of neuroectodermal differentiation, ranging from the least differentiated (Ewing's sarcoma) to the most differentiated (peripheral Neuroepithelioma).Case report: We present a patient with a peripheral neuroectodermal tumor located in the neck and another one with a peripheral neuroectodermal tumor of the mandibular condyle. Discussion: Peripheral neuroectodermal tumors are a very rare and aggressive tumors. They characteristically reveal the presence of small round cells and a translocation of the gene EWS. The prognosis in overall is very poor. Due to the small numbers of cases published the best treatment is not well defined
M. Adrados - One of the best experts on this subject based on the ideXlab platform.
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Tumores neuroectodérmicos primitivos periféricos de localización en el área orocervical: presentación de dos casos clínicos Peripheral primitive neuroectodermal tumors located in orocervical area: presentation of two clinical cases
Elsevier, 2010Co-Authors: Sánchez C. Acedo, M.f. Muñoz Guerra, Naval L. Gías, P.l. Martos, M. AdradosAbstract:Introducción: Los tumores neuroectodérmicos primitivos (PNET, de primitive neuroectodermal tumors) son una familia de neoplasias malignas de células pequeñas y redondas, que derivan de la cresta neural. Se distinguen tres tipos: PNET del sistema nervioso central, PNET del sistema nervioso autónomo y PNET periféricos. Los más frecuentes dentro del grupo de PNET periféricos son el neuroepitelioma periférico y el sarcoma de Ewing, que se consideran la misma neoplasia pero con diferente grado de diferenciación. Casos clínicos: Presentamos dos casos de PNET periféricos, uno de aparición en la región cervical y otro originado en el cóndilo mandibular. Discusión: Los PNET son neoplasias muy raras y altamente agresivas. En todos ellos aparecen células redondas pequeñas poco diferenciadas y una traslocación cromosómica característica del gen EWS. En general se considera que tienen un pronóstico desfavorable. Además, la baja frecuencia de estos tumores, así como la escasez de casos publicados hacen difícil valorar el tratamiento más adecuado.Introduction: Peripheral primitive neuroectodermal tumors (PNET) are a family of smallround cell tumors of presumed neuroectodermal origin. This broad family can be subdivided into three major groups: PNET from the central nervous system, PNET from the autonomic nervous system or peripheral PNET. Ewing´s sarcoma and peripheral neuroepitelioma, the two most frequently encountered members of the peripheral PNET family, are considered to represent a spectrum according to the extent of neuroectodermal differentiation, ranging from the least differentiated (Ewing´s sarcoma) to the most differentiated (peripheral Neuroepithelioma). Case report: We present a patient with a peripheral neuroectodermal tumor located in the neck and another one with a peripheral neuroectodermal tumor of the mandibular condyle. Discussion: Peripheral neuroectodermal tumors are a very rare and aggressive tumors. They characteristically reveal the presence of small round cells and a translocation of the gene EWS. The prognosis in overall is very poor. Due to the small numbers of cases published the best treatment is not well defined
Alain Aurias - One of the best experts on this subject based on the ideXlab platform.
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interphase molecular cytogenetics of ewing s sarcoma and peripheral Neuroepithelioma t 11 22 with flanking and overlapping cosmid probes
Cancer Genetics and Cytogenetics, 1994Co-Authors: Chantal Desmaze, Jessica Zucman, Olivier Delattre, Thomas Melot, Gilles Thomas, Alain AuriasAbstract:Abstract The translocation, t(11;22)(q24;q12), recurrently observed in Ewing's sarcoma and in peripheral Neuroepithelioma has been recently cloned. The analysis of a series of ES/PNE has revealed that the chromosome 22 breakpoints are clustered in a small region of 7 kb, called EWSR1, and that those on chromosome 11 are spread over a larger region of 40–50 kb, called EWSR2. Cosmids from loci flanking or overlapping these two regions have been obtained. We demonstrate here that fluorescence in situ hybridization (FISH) with these cosmids allows the localization of the two breakpoints with a 10-kb resolution and leads to a rapid and reliable ES/PNE diagnosis.
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cloning and characterization of the ewing s sarcoma and peripheral Neuroepithelioma t 11 22 translocation breakpoints
Genes Chromosomes and Cancer, 1992Co-Authors: Jessica Zucman, Olivier Delattre, Chantal Desmaze, Beatrice Plougastel, Isabelle Joubert, Thomas Melot, Martine Peter, Pieter J De Jong, Guy A Rouleau, Alain AuriasAbstract:Ewing's sarcoma (ES) and peripheral Neuroepithelioma (PN) are related tumors, possibly of neural crest origin, which are cytogenetically characterized by the specific translocation t(11;22)(q24;q 12). The cos5 locus, previously identified in the vicinity of the chromosome 22 breakpoint of this translocation, was shown by in situ hybridization on interphase nuclei to lie between VIIIF2 and LIF, two loci located on either side of the breakpoint and at a distance of less than 2,000 kb. The progressive expansion of this locus by chromosome walking led to the construction of a 300 kb contig, which finally crossed the breakpoint. The subsequent cloning of the two translocation junction fragments of a PN, followed by the molecular characterization of the translocation breakpoints of 20 ES and PN, showed that most chromosome 22 breakpoints are clustered within a small, 2 kb region. In contrast, the chromosome 11 breakpoints are scattered over a region of at least 40 kb. The translocation leads to the synthesis of a chimeric transcript that links sequences from chromosomes 22 and 11. Finally, no evidence was found of any specific difference in the position of ES and PN translocation breakpoints.
Goldie Y L Lui - One of the best experts on this subject based on the ideXlab platform.
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the iron chelator deferasirox as a novel strategy for cancer treatment oral activity against human lung tumor xenografts and molecular mechanism of action
Molecular Pharmacology, 2013Co-Authors: Goldie Y L Lui, Peyman Obeidy, Samuel J Ford, Chris Tselepis, Danae M Sharp, Patric J Jansson, Danuta S Kalinowski, Zaklina Kovacevic, David B Lovejoy, Des R RichardsonAbstract:Deferasirox is an orally effective iron (Fe) chelator currently used for the treatment of iron-overload disease and has been implemented as an alternative to the gold standard chelator, desferrioxamine (DFO). Earlier studies demonstrated that DFO exhibits anticancer activity due to its ability to deplete cancer cells of iron. In this investigation, we examined the in vitro and in vivo activity of deferasirox against cells from human solid tumors. To date, there have been no studies to investigate the effect of deferasirox on these types of tumors in vivo. Deferasirox demonstrated similar activity at inhibiting proliferation of DMS-53 lung carcinoma and SK-N-MC Neuroepithelioma cell lines compared with DFO. Furthermore, deferasirox was generally similar or slightly more effective than DFO at mobilizing cellular 59Fe and inhibiting iron uptake from human transferrin depending on the cell type. However, deferasirox potently inhibited DMS-53 xenograft growth in nude mice when given by oral gavage, with no marked alterations in normal tissue histology. To understand the antitumor activity of deferasirox, we investigated its effect on the expression of molecules that play key roles in metastasis, cell cycle control, and apoptosis. We demonstrated that deferasirox increased expression of the metastasis suppressor protein N -myc downstream-regulated gene 1 and upregulated the cyclin-dependent kinase inhibitor p21CIP1/WAF1 while decreasing cyclin D1 levels. Moreover, this agent increased the expression of apoptosis markers, including cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase 1. Collectively, we demonstrate that deferasirox is an orally effective antitumor agent against solid tumors.