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1.
BMC Cancer ; 16(1): 746, 2016 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-27658583

RESUMEN

BACKGROUND: Several studies show that bone marrow (BM) microenvironment and hypoxia condition can promote the survival of leukemic cells and induce resistance to anti-leukemic drugs. However, the molecular mechanism for chemoresistance by hypoxia is not fully understood. METHODS: In the present study, we investigated the effect of hypoxia on resistance to two therapies, methotrexate (MTX) and prednisolone (PRD), in two cell models for acute lymphoblastic leukemia (ALL). To look for an implication of hypoxia in chemoresistance, cell viability, total cell density and cell proliferation were analyzed. Survival and death signaling pathways were also screened by "reverse phase protein array" (RPPA) and western blotting experiments conducted on selected proteins to confirm the results. RESULTS: We found that hypoxia promotes chemoresistance in both ALL cell lines. The induction of drug-resistance by hypoxia was not associated with an increase in total cell density nor an increase in cell proliferation. Using RPPA, we show that chemoresistance induced by hypoxia was mediated through an alteration of cell death signaling pathways. This protective effect of hypoxia seems to occur via a decrease in pro-apoptotic proteins and an increase in anti-apoptotic proteins. The results were confirmed by immunoblotting. Indeed, hypoxia is able to modulate the expression of anti-apoptotic proteins independently of chemotherapy while a pro-apoptotic signal induced by a chemotherapy is not modulated by hypoxia. CONCLUSIONS: Hypoxia is a factor in leukemia cell resistance and for two conventional chemotherapies modulates cell death signaling pathways without affecting total cell density or cell proliferation.


Asunto(s)
Apoptosis/fisiología , Hipoxia de la Célula/fisiología , Resistencia a Antineoplásicos/fisiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Transducción de Señal/fisiología , Línea Celular Tumoral , Supervivencia Celular , Humanos
2.
Ann Pharm Fr ; 73(2): 100-7, 2015 Mar.
Artículo en Francés | MEDLINE | ID: mdl-25745942

RESUMEN

Inhibition of the vascular endothelial growth factor A or inhibition of its receptors are currently used for the treatment of cancer. However, the results are still modest, especially because of the multitude and redundancy of angiogenic factors. It can be hypothesized that therapies targeting directly endothelial cells themselves could be more effective. The tetraspanins are transmembrane molecules, which are devoid of intrinsic enzymatic activity but can associate with each other and with other molecules such as integrins or proteins of the immunoglobulin superfamily to form a network. The tetraspanins are present on the surface of endothelial cells and in vitro, inhibition of these molecules by antibodies or small interfering RNA suggests that tetraspanins play a role in angiogenesis. These preliminary data have been confirmed by the study of cancer xenografts in tetraspanin-deficient mice, which have a significant decrease in tumor size and tumor angiogenesis. In vivo, it has been shown that intravenous administration of a monoclonal antibody (ALB6) directed against CD9 decreases the tumor growth and angiogenesis and that intravitreal injection of a small interfering RNA decreasing CD9 significantly inhibits choroidal neovascularization induced by laser. Finally, anti-angiogenic effects and potent anti-tumor activity are observed by the intraperitoneal administration of GS-168AT2, a peptide derived from CD9-Partner 1, a molecule belonging to the immunoglobulin superfamily, which interacts strongly with the CD9 and CD81. These data suggest that the pharmacological modulation of the tetraspanin web could play a new promising anti-angiogenic strategy.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Inhibidores de la Angiogénesis/uso terapéutico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Tetraspaninas/efectos de los fármacos , Animales , Humanos , Ratones , Neoplasias/irrigación sanguínea , Tetraspanina 29/antagonistas & inhibidores
3.
Pharmacol Res ; 77: 11-21, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24004656

RESUMEN

Neuroblastoma malignant cell growth is dependent on their undifferentiated status. Arsenic trioxide (As2O3) induces neuroblastoma cell differentiation in vitro, but its mechanisms still remains unknown. We used three human neuroblastoma cell lines (SH-SY5Y, IGR-N-91, LAN-1) that differ from their MYCN and p53 status to explore the intracellular events activated by As2O3 and involved in neurite outgrowth, a morphological marker of differentiation. As2O3 (2µM) induced neurite outgrowth in all cell lines, which was dependent on ERK activation but independent on MYCN status. This process was induced either by a sustained (3 days) or a transient (2h) incubation with As2O3, indicating that very early events trigger the induction of differentiation. In parallel, As2O3 induced a rapid assembly of promyelocytic leukemia nuclear bodies (PML-NB) in an ERK-dependent manner. In conclusion, mechanisms leading to neuroblastoma cell differentiation in response to As2O3 appear to involve the ERK pathway activation and PML-NB formation, which are observed in response to other differentiating molecules such as retinoic acid derivates. This open new perspectives based on the use of treatment combinations to potentiate the differentiating effects of each drug alone and reduce their adverse side effects.


Asunto(s)
Antineoplásicos/farmacología , Arsenicales/farmacología , Diferenciación Celular/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Cuerpos de Inclusión Intranucleares/metabolismo , Leucemia Promielocítica Aguda/patología , Neuroblastoma/patología , Proteínas Nucleares/metabolismo , Óxidos/farmacología , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Trióxido de Arsénico , Arsenicales/uso terapéutico , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Activación Enzimática/efectos de los fármacos , Humanos , Cuerpos de Inclusión Intranucleares/efectos de los fármacos , Leucemia Promielocítica Aguda/tratamiento farmacológico , Leucemia Promielocítica Aguda/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteína Proto-Oncogénica N-Myc , Neuritas/efectos de los fármacos , Neuritas/ultraestructura , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/metabolismo , Proteínas Oncogénicas/metabolismo , Óxidos/uso terapéutico , Proteína de la Leucemia Promielocítica
4.
Forensic Sci Int Genet ; 56: 102596, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34763164

RESUMEN

The analysis of DNA methylation has become an established method for chronological age estimation. This has triggered interest in the forensic community to develop new methods for age estimation from biological crime scene material. Various assays are available for age estimation from somatic tissues, the majority from blood. Age prediction from semen requires different DNA methylation markers and the only assays currently developed for forensic analysis are based on SNaPshot or pyrosequencing. Here, we describe a new assay using massively parallel sequencing to analyse 13 candidate CpG sites targeted in two multiplex PCRs. The assay has been validated by five consortium laboratories of the VISible Attributes through GEnomics (VISAGE) project within a collaborative exercise and was tested for reproducible quantification of DNA methylation levels and sensitivity with DNA methylation controls. Furthermore, DNA extracts and stains on Whatman FTA cards from two semen samples were used to evaluate concordance and mimic casework samples. Overall, the assay yielded high read depths (> 1000 reads) at all 13 marker positions. The methylation values obtained indicated robust quantification with an average standard deviation of 2.8% at the expected methylation level of 50% across the 13 markers and a good performance with 50 ng DNA input into bisulfite conversion. The absolute difference of quantifications from one participating laboratory to the mean quantifications of concordance and semen stains of remaining laboratories was approximately 1%. These results demonstrated the assay to be robust and suitable for age estimation from semen in forensic investigations. In addition to the 13-marker assay, a more streamlined protocol combining only five age markers in one multiplex PCR was developed. Preliminary results showed no substantial differences in DNA methylation quantification between the two assays, indicating its applicability with the VISAGE age model for semen developed with data from the complete 13-marker tool.


Asunto(s)
Metilación de ADN , Semen , Islas de CpG , Genética Forense , Humanos , Laboratorios , Análisis de Secuencia de ADN
5.
Br J Cancer ; 104(3): 496-504, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21206492

RESUMEN

BACKGROUND: Loss of CD9 expression has been correlated with a higher motility and metastatic potential of tumour cells originating from different organs. However, the mechanism underlying this loss is not yet understood. METHODS: We produced a truncated form of partner 1 of CD9 (CD9P-1), GS-168AT2, and developed a new monoclonal antibody directed towards the latter. We measured the expression of CD9 and CD9P-1 in human lung tumours (hLTs), and monitored the level of CD9 in NCI-H460, in vitro and in vivo, in the presence and absence of GS-168AT2. RESULTS: Loss of CD9 is inversely related to the expression of CD9P-1, which correlates with the metastatic status of hLT (n=55). In vitro, GS-168AT2 is rapidly internalised and degraded at both the membrane and cytoplasm of NCI-H460, and this correlates with the association of GS-168AT2 with both CD9 and CD81. Intraperitoneal injections of GS-168AT2 in NCI-H460-xenografted Nude mice led to drastic inhibition of tumour growth, as well as to the downregulation of CD9, but not of CD81, in the tumour core. CONCLUSION: These findings show for the first time that CD9P-1 expression positively correlates with the metastatic status of hLT, and that the upregulation of CD9P-1 expression could be one of the mechanisms underlying the loss of CD9 in solid tumours. Our study also reveals that, under certain conditions, loss of CD9 could be a tumour growth-limiting phenomenon rather than a tumour growth-promoting one.


Asunto(s)
Neoplasias Pulmonares/genética , Proteínas de Neoplasias/genética , Animales , Línea Celular Tumoral , Proliferación Celular , Femenino , Expresión Génica , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/secundario , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Br J Cancer ; 105(7): 1002-11, 2011 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-21863033

RESUMEN

BACKGROUND: Tetraspanins are transmembrane proteins known to contribute to angiogenesis. CD9 partner-1 (CD9P-1/EWI-F), a glycosylated type 1 transmembrane immunoglobulin, is a member of the tetraspanin web, but its role in angiogenesis remains to be elucidated. METHODS: We measured the expression of CD9P-1 under angiogenic and angiostatic conditions, and the influence of its knockdown onto capillary structures formation by human endothelial cells (hECs). A truncated form of CDP-1, GS-168AT2, was produced and challenged vs hEC proliferation, migration and capillaries' formation. Its association with CD9P-1, CD9, CD81 and CD151 and the expressions of these later at hEC surface were analysed. Finally, its effects onto in vivo tumour-induced angiogenesis and tumour growth were investigated. RESULTS: Vascular endothelial growth factor (VEGF)-induced capillary tube-like formation was inhibited by tumour necrosis factor α and was associated with a rise in CD9P-1 mRNA expression (P<0.05); accordingly, knockdown of CD9P-1 inhibited VEGF-dependent in vitro angiogenesis. GS-168AT2 dose-dependently inhibited in vitro angiogenesis, hEC migration and proliferation (P<0.05). Co-precipitation experiments suggest that GS-168AT2 corresponds to the sequence by which CD9P-1 physiologically associates with CD81. GS-168AT2 induced the depletion of CD151, CD9 and CD9P-1 from hEC surface, correlating with GS-168AT2 degradation. Finally, in vivo injections of GS-168AT2 inhibited tumour-associated angiogenesis by 53.4±9.5% (P=0.03), and reduced tumour growth of Calu 6 tumour xenografts by 73.9±16.4% (P=0.007) without bodyweight loss. CONCLUSION: The truncated form of CD9P-1, GS-168AT2, potently inhibits angiogenesis and cell migration by at least the downregulation of CD151 and CD9, which provides the first evidences for the central role of CD9P-1 in tumour-associated angiogenesis and tumour growth.


Asunto(s)
Neoplasias Pulmonares/irrigación sanguínea , Neoplasias Pulmonares/prevención & control , Proteínas de Neoplasias/metabolismo , Neovascularización Patológica/prevención & control , Animales , Aorta/citología , Aorta/metabolismo , Apoptosis , Western Blotting , Bovinos , Proliferación Celular , Células Cultivadas , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Femenino , Citometría de Flujo , Humanos , Técnicas para Inmunoenzimas , Inmunoprecipitación , Neoplasias Pulmonares/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , ARN Mensajero/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Venas Umbilicales/citología , Venas Umbilicales/metabolismo
7.
Proc Biol Sci ; 276(1667): 2567-74, 2009 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-19403536

RESUMEN

Exceptional fossil specimens with preserved soft parts from the Maotianshan Shale (ca 520 Myr ago) and the Burgess Shale (505 Myr ago) biotas indicate that the worldwide distributed bivalved arthropod Isoxys was probably a non-benthic visual predator. New lines of evidence come from the functional morphology of its powerful prehensile frontal appendages that, combined with large spherical eyes, are thought to have played a key role in the recognition and capture of swimming or epibenthic prey. The swimming and steering of this arthropod was achieved by the beating of multiple setose exopods and a flap-like telson. The appendage morphology of Isoxys indicates possible phylogenetical relationships with the megacheirans, a widespread group of assumed predator arthropods characterized by a pre-oral 'great appendage'. Evidence from functional morphology and taphonomy suggests that Isoxys was able to migrate through the water column and was possibly exploiting hyperbenthic niches for food. Although certainly not unique, the case of Isoxys supports the idea that off-bottom animal interactions such as predation, associated with complex feeding strategies and behaviours (e.g. vertical migration and hunting) were established by the Early Cambrian. It also suggests that a prototype of a pelagic food chain had already started to build-up at least in the lower levels of the water column.


Asunto(s)
Artrópodos/genética , Evolución Biológica , Fósiles , Conducta Predatoria , Animales
8.
Hum Reprod ; 24(1): 37-44, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18945713

RESUMEN

BACKGROUND: Sperm banking is a suitable procedure to prevent infertility after cancer therapy in male adolescents. We evaluated the feasibility of semen preservation in 156 adolescents aged between 13 and 20 years and then we assessed fertility outcome after treatment. METHODS: Age, urogenital history, indications for cryopreservation, histological diagnosis and semen parameters were recorded. Fertility status after treatment was assessed by a questionnaire addressed to those patients who had utilized sperm storage. Post-treatment semen analysis was performed for 22 patients. RESULTS: Cryopreservation was possible in 88.5% of cases. Azoospermia was detected in 2.6% of the patients at the time of diagnosis. Malignant disease accounted for 84% of our male adolescents. In this type of disease, semen parameters were significantly altered only among patients with metastatic malignant bone tumour. After treatment, nine patients presented azoospermia, five patients achieved pregnancy spontaneously, two achieved it after assisted reproductive technique using fresh ejaculated spermatozoa and one following sperm donation. Three failed with cryopreserved sperm. CONCLUSIONS: Semen cryopreservation is possible for most adolescents and, regardless of disease type, may be a means of preserving fertility prior to gonadotoxic treatment that might impair the spermatogenesis process.


Asunto(s)
Criopreservación , Fertilidad , Hospitales Universitarios , Preservación de Semen , Adolescente , Francia , Humanos , Masculino , Neoplasias/terapia , Estudios Retrospectivos , Recuento de Espermatozoides , Motilidad Espermática , Espermatozoides/citología , Adulto Joven
9.
J Neurochem ; 104(1): 89-99, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17986232

RESUMEN

Neuroblastoma is one of the most common cancers in children. Neuroblastoma differentiation is linked to the presence of the promyelocytic leukemia (PML) protein. Retinoic acid, a powerful differentiation-inducer in vitro, is a potent agent for the treatment of neuroblastoma. Using two different human neuroblastoma cell lines, SH-SY5Y and LA-N-5, we show here that PML protein leads to the formation of nuclear bodies (PML-NB) after only 1 h of retinoic acid treatment and that this formation is mediated by the extracellular signal-regulated kinase (ERK) pathway. Inhibition of protein kinase C also leads to formation of PML-NB via the ERK pathway. Both sumoylation and phosphorylation of PML in an ERK-dependent pathway are also required for formation of PML-NB. Finally, we show that PML-NB formation in neuroblastoma cells is associated with neurite outgrowth. These results support the proposal that the formation of PML-NB is correlated with the differentiation of neuroblastoma cells.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Estructuras del Núcleo Celular/metabolismo , Queratolíticos/farmacología , Proteínas de Neoplasias/metabolismo , Neuroblastoma/tratamiento farmacológico , Proteínas Nucleares/metabolismo , Factores de Transcripción/metabolismo , Tretinoina/farmacología , Proteínas Supresoras de Tumor/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Modelos Biológicos , Proteínas de Neoplasias/genética , Neuroblastoma/patología , Proteínas Nucleares/genética , Fosforilación/efectos de los fármacos , Proteína de la Leucemia Promielocítica , Transducción de Señal/efectos de los fármacos , Factores de Transcripción/genética , Proteínas Supresoras de Tumor/genética
10.
Leukemia ; 21(2): 238-47, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17170721

RESUMEN

The objective of the study was to assess acute neurotoxicity associated with triple intrathecal therapy (TIT)+/-high-dose methotrexate (HD MTX) in children with acute lymphoblastic leukemia (ALL). 1395 children were enrolled on FRALLE 93 protocol from 1993 to 1999. Lower-risk group (LR, n=182) were randomized to weekly low-dose MTX at 25 mg/m(2)/week (LD MTX, n=81) or HD MTX at 1.5 g/m(2)/2 weeks x 6 (n=77). Intermediate-risk group (IR, n=672) were randomized to LD MTX (n=290) or HD MTX at 8 g/m(2)/2 weeks x 4 (n=316). Higher-risk group (HR, n=541) prednisone-responder patients received LD MTX and cranial radiotherapy. HR group steroid resistant cases were grafted (autologous or allogenic). TIT (MTX, cytarabine and methylprednisolone) was given every 2 weeks during 16-18 weeks and every 3 months during maintenance therapy in LR and IR patients. 52 patients (3.7%) developed neurotoxicity. Isolated seizures: n=15 (1.1%), peripheral and spinal neuropathy: n=17 (1.2%) and encephalopathy: n=20 (1.4%). Age >10 years was significantly associated with neurotoxicity (P=0.01) and use of HD MTX is associated with encephalopathy (P=0.03). Sequels are reported respectively in 60 and 33% of spinal neuropathy and encephalopathy cases. Current strategies tailoring risk of neurological sequels has to be defined.


Asunto(s)
Antimetabolitos Antineoplásicos/efectos adversos , Encefalopatías Metabólicas/inducido químicamente , Metotrexato/efectos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Adolescente , Factores de Edad , Encefalopatías Metabólicas/epidemiología , Encefalopatías Metabólicas/prevención & control , Niño , Preescolar , Terapia Combinada , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Lactante , Masculino , Neurotoxinas , Leucemia-Linfoma Linfoblástico de Células Precursoras/radioterapia , Medición de Riesgo
11.
J Pediatr Endocrinol Metab ; 21(12): 1169-78, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19189691

RESUMEN

Primary germ cell tumors (PGCT) of the central nervous system usually develop in the third ventricle area, and most frequently in the pineal region. The suprasellar region is the second preferential site for development of these tumors which are rarely simultaneously present in these two sites. We report five new cases of PGCT with pineal and suprasellar localizations, which appeared in late puberty in four boys and one girl aged 17-19 years. The clinical picture associated signs of intracranial hypertension, convergence and verticality palsies, diabetes insipidus and pituitary deficiency. Encephalic MRI revealed a double localization. Endocrine tests revealed a particular pattern associating central diabetes insipidus and a hypothalamic-pituitary disconnection syndrome. Following identification of the pathological type of lesions via a neurosurgical approach, treatment was based on a combined method using chemotherapy, radiotherapy and hormone replacement. Based on this treatment, prolonged remissions were obtained with a good quality of life.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Sistema Hipotálamo-Hipofisario/metabolismo , Neoplasias de Células Germinales y Embrionarias/diagnóstico , Neoplasias Primarias Múltiples/diagnóstico , Pinealoma/diagnóstico , Neoplasias Hipofisarias/diagnóstico , Adolescente , Hormona Adrenocorticotrópica/sangre , Neoplasias Encefálicas/sangre , Neoplasias Encefálicas/terapia , Terapia Combinada , Quimioterapia , Femenino , Estudios de Seguimiento , Hormonas Esteroides Gonadales/sangre , Hormona del Crecimiento/sangre , Terapia de Reemplazo de Hormonas , Humanos , Hidrocortisona/sangre , Masculino , Neoplasias de Células Germinales y Embrionarias/sangre , Neoplasias de Células Germinales y Embrionarias/terapia , Neoplasias Primarias Múltiples/sangre , Neoplasias Primarias Múltiples/terapia , Glándula Pineal/patología , Pinealoma/sangre , Pinealoma/terapia , Neoplasias Hipofisarias/sangre , Neoplasias Hipofisarias/terapia , Pronóstico , Radioterapia , Tirotropina/sangre , Adulto Joven
12.
Forensic Sci Int Genet ; 34: 105-115, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29453107

RESUMEN

In a previous study we presented an assay for targeted mRNA sequencing for the identification of human body fluids, optimised for the Illumina MiSeq/FGx MPS platform. This assay, together with an additional in-house designed assay for the Ion Torrent PGM/S5 platform, was the basis for a collaborative exercise within 17 EUROFORGEN and EDNAP laboratories, in order to test the efficacy of targeted mRNA sequencing to identify body fluids. The task was to analyse the supplied dried body fluid stains and, optionally, participants' own bona fide or mock casework samples of human origin, according to specified protocols. The provided primer pools for the Illumina MiSeq/FGx and the Ion Torrent PGM/S5 platforms included 33 and 29 body fluid specific targets, respectively, to identify blood, saliva, semen, vaginal secretion, menstrual blood and skin. The results demonstrated moderate to high count values in the body fluid or tissue of interest with little to no counts in non-target body fluids. There was some inter-laboratory variability in read counts, but overall the results of the laboratories were comparable in that highly expressed markers showed high read counts and less expressed markers showed lower counts. We performed a partial least squares (PLS) analysis on the data, where blood, menstrual blood, saliva and semen markers and samples clustered well. The results of this collaborative mRNA massively parallel sequencing (MPS) exercise support targeted mRNA sequencing as a reliable body fluid identification method that could be added to the repertoire of forensic MPS panels.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , ARN Mensajero/metabolismo , Análisis Químico de la Sangre , Moco del Cuello Uterino/química , Femenino , Marcadores Genéticos , Humanos , Laboratorios , Análisis de los Mínimos Cuadrados , Masculino , Menstruación , Saliva/química , Semen/química , Piel/química
13.
Proc Biol Sci ; 274(1625): 2555-61, 2007 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-17698484

RESUMEN

The diverse and exceptionally well-preserved pycnogonids described herein from the Middle Jurassic La Voulte Lagerstätte fill a 400 Myr gap of knowledge in the evolutionary history of this enigmatic group of marine arthropods. They reveal very close morphological and functional (locomotion, feeding) similarities with present-day pycnogonids and, by contrast, marked differences with all Palaeozoic representatives of the group. This suggests a relatively recent, possibly Mesozoic origin for at least three major extant lineages of pycnogonids (Ammotheidae, Colossendeidae, Endeidae). Combined evidence from depositional environment, faunal associates and recent analogues indicate that the La Voulte pycnogonids probably lived in the upper bathyal zone (ca 200 m). Our results point to a remarkable morphological and ecological stability of this arthropod group over at least 160 Myr and suggest that the colonization of the deep sea by pycnogonids occurred before the Jurassic.


Asunto(s)
Artrópodos/anatomía & histología , Artrópodos/clasificación , Fósiles , Animales , Francia , Biología Marina , Filogenia , Factores de Tiempo
14.
Proc Biol Sci ; 274(1610): 627-33, 2007 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-17254986

RESUMEN

Although palaeontological evidence from exceptional biota demonstrates the existence of diverse marine communities in the Early Cambrian (approx. 540-520 Myr ago), little is known concerning the functioning of the marine ecosystem, especially its trophic structure and the full range of ecological niches colonized by the fauna. The presence of a diverse zooplankton in Early Cambrian oceans is still an open issue. Here we provide compelling evidence that chaetognaths, an important element of modern zooplankton, were present in the Early Cambrian Chengjiang biota with morphologies almost identical to Recent forms. New information obtained from the lowermost Cambrian of China added to previous studies provide convincing evidence that protoconodont-bearing animals also belonged to chaetognaths. Chaetognaths were probably widespread and diverse in the earliest Cambrian. The obvious raptorial function of their circumoral apparatuses (grasping spines) places them among the earliest active predator metazoans. Morphology, body ratios and distribution suggest that the ancestral chaetognaths were planktonic with possible ecological preferences for hyperbenthic niches close to the sea bottom. Our results point to the early introduction of prey-predator relationships into the pelagic realm, and to the increase of trophic complexity (three-level structure) during the Precambrian-Cambrian transition, thus laying the foundations of present-day marine food chains.


Asunto(s)
Evolución Biológica , Ecosistema , Cadena Alimentaria , Fósiles , Invertebrados/anatomía & histología , Animales , China
15.
Leuk Res ; 31(5): 629-38, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17011029

RESUMEN

Angiogenic factors such as basic fibroblast growth factor (bFGF) or vascular endothelial growth factor (VEGF) were previously studied in childhood acute lymphoblastic leukaemia (ALL) but little is known concerning the anti-angiogenic response in ALL. At diagnosis, the plasma levels of the anti-angiogenic factor endostatin were significantly higher in 33 children with ALL than in controls (median values 17.7 and 7.6 ng/ml, respectively, p=0.0192) but no relationship was observed with plasma bFGF or VEGF levels. The highest levels were observed in patients with an hyperdiploïd karyotype. Expression of mRNA for collagen XVIII/endostatin in lymphoblasts was detected in 19/24 cases but protein secretion was found only in 14/28 supernatants of cultured lymphoblasts. No direct relationship appeared between secretion of endostatin by lymphoblasts and plasma levels. In addition, endostatin levels remained elevated in remission, suggesting that endostatin could have a stromal origin as well. No prognostic value of plasma endostatin could be assessed. In conclusion, the present data indicate that an anti-angiogenic response is observed in some ALL children, but its physiopathological importance remains to be established.


Asunto(s)
Endostatinas/metabolismo , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Recurrencia Local de Neoplasia/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre , Leucemia-Linfoma Linfoblástico de Células Precursoras/orina , Factor A de Crecimiento Endotelial Vascular/metabolismo , Adolescente , Western Blotting , Estudios de Casos y Controles , Proliferación Celular , Niño , Preescolar , Endostatinas/genética , Ensayo de Inmunoadsorción Enzimática , Factor 2 de Crecimiento de Fibroblastos/genética , Hepatomegalia , Humanos , Técnicas para Inmunoenzimas , Inmunofenotipificación , Lactante , Linfocitos/metabolismo , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Neovascularización Patológica , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Inducción de Remisión , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor A de Crecimiento Endotelial Vascular/genética
16.
Bone Marrow Transplant ; 52(5): 678-682, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28112748

RESUMEN

Allogeneic hematopoietic stem cell transplantation (SCT) contributes to improved outcome in childhood acute leukemia (AL). However, therapeutic options are poorly defined in the case of post-transplantation relapse. We aimed to compare treatment strategies in 334 consecutive children with acute leukemia relapse or progression after SCT in a recent 10-year period. Data could be analyzed in 288 patients (157 ALL, 123 AML and 8 biphenotypic AL) with a median age of 8.16 years at transplantation. The median delay from first SCT to relapse or progression was 182 days. The treatment consisted of chemotherapy alone (n=108), chemotherapy followed by second SCT (n=70), supportive/palliative care (n=67), combination of chemotherapy and donor lymphocyte infusion (DLI; n=30), or isolated reinfusion of donor lymphocytes (DLI; n=13). The median OS duration after relapse was 164 days and differed according to therapy: DLI after chemotherapy=385 days, second allograft=391 days, chemotherapy=174 days, DLI alone=140 days, palliative care=43 days. A second SCT or a combination of chemotherapy and DLI yielded similar outcome (hazard ratio (HR)=0.85, P=0.53) unlike chemotherapy alone (HR=1.43 P=0.04), palliative care (HR=4.24, P<0.0001) or isolated DLI (HR=1,94, P<0.04). Despite limitations in this retrospective setting, strategies including immunointervention appear superior to other approaches, mostly in AML.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/métodos , Leucemia/terapia , Enfermedad Aguda , Niño , Progresión de la Enfermedad , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Leucemia/mortalidad , Leucemia Bifenotípica Aguda/mortalidad , Leucemia Bifenotípica Aguda/terapia , Leucemia Mieloide Aguda/mortalidad , Leucemia Mieloide Aguda/terapia , Transfusión de Linfocitos , Cuidados Paliativos , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Estudios Retrospectivos , Tasa de Supervivencia , Trasplante Homólogo , Insuficiencia del Tratamiento , Resultado del Tratamiento
17.
Bone Marrow Transplant ; 52(4): 516-521, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27941778

RESUMEN

We analyzed the impact of cytogenetics on 193 children enrolled in two successive French trials (LAME89/91 and ELAM02), who received hematopoietic stem cell transplantation during CR1. Detailed karyotype was available for 66/74 (89%) in LAME89/91 and 118/119 (99%) in ELAM02. Several karyotype and transplant characteristics differed according to therapeutic protocol: unfavorable karyotypes were more frequent in ELAM02 (36% vs 18%), pretransplant chemotherapy included high-dose cytarabine in ELAM02 and not in LAME89/91, IV replaced oral busulfan in the conditioning regimen, methotrexate was removed from post-transplant immunosuppression, and matched unrelated donor and cord blood transplantation were introduced. Five-year overall survival (OS) was 78.2% in LAME89 and 81.4% in ELAM02. OS was significantly lower for the unfavorable cytogenetic risk group in LAME89/91 when compared with intermediate and favorable groups (50% vs 90.6 and 86.4%, P=0.001). This difference was no longer apparent in ELAM02 (80.9% vs 71.3% and 5/5, respectively). Survival improvement for children with unfavorable karyotype was statistically significant (P=0.026) and was due to decrease in relapse risk. Five-year transplantation-related mortality was 6.75% in LAME89/91. In ELAM02, it was 3.2% for patients with a sibling donor and 10.9% with an unrelated donor or cord blood. We conclude that the outcome of children with unfavorable karyotype transplanted in CR1 has improved.


Asunto(s)
Citogenética , Trasplante de Células Madre Hematopoyéticas/métodos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Niño , Femenino , Francia , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Cariotipificación , Leucemia Mieloide Aguda/mortalidad , Masculino , Inducción de Remisión , Análisis de Supervivencia , Trasplante Homólogo , Resultado del Tratamiento
18.
Hum Gene Ther ; 17(10): 1019-26, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17007568

RESUMEN

Overexpression of RhoA in cancer indicates a poor prognosis, because of increased tumor cell proliferation and invasion and tumor angiogenesis. We showed previously that anti-RhoA small interfering RNA (siRNA) inhibited aggressive breast cancer more effectively than conventional blockers of Rho-mediated signaling pathways. This study reports the efficacy and lack of toxicity of intravenously administered encapsulated anti-RhoA siRNA in chitosan-coated polyisohexylcyanoacrylate (PIHCA) nanoparticles in xenografted aggressive breast cancers (MDA-MB-231). The siRNA was administered every 3 days at a dose of 150 or 1500 microg/kg body weight in nude mice. This treatment inhibited the growth of tumors by 90% in the 150-microg group and by even more in the 1500-microg group. Necrotic areas were observed in tumors from animals treated with anti-RhoA siRNA at 1500 microg/kg, resulting from angiogenesis inhibition. In addition, this therapy was found to be devoid of toxic effects, as evidenced by similarities between control and treated animals for the following parameters: body weight gain; biochemical markers of hepatic, renal, and pancreatic function; and macroscopic appearance of organs after 30 days of treatment. Because of its efficacy and the absence of toxicity, it is suggested that this strategy of anti-RhoA siRNA holds significant promise for the treatment of aggressive cancers.


Asunto(s)
Neoplasias de la Mama/terapia , Quitosano/administración & dosificación , Bombas de Infusión , Trasplante de Neoplasias/normas , ARN Interferente Pequeño/administración & dosificación , Proteína de Unión al GTP rhoA/genética , Animales , Neoplasias de la Mama/irrigación sanguínea , Línea Celular Tumoral , Quitosano/uso terapéutico , Quitosano/toxicidad , Humanos , Ratones , Nanopartículas/administración & dosificación , Nanopartículas/uso terapéutico , Nanopartículas/toxicidad , Trasplante de Neoplasias/métodos , Neoplasias/fisiopatología , Neovascularización Patológica/terapia , ARN Interferente Pequeño/uso terapéutico , ARN Interferente Pequeño/toxicidad
19.
Leukemia ; 19(12): 2082-9, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16121218

RESUMEN

From 1989 to 1998, 341 children were included in the French multicentric LAME (Leucémie Aiguë Myéloblastique Enfant) trials. A total of 309 children were registered in the LAME 89/91 protocol. This intensive regimen included an induction phase (mitoxantrone plus cytarabine), two consolidation courses, one containing timed-sequential high-dose cytarabine, asparaginase and amsacrine; 276 (90%) achieved a CR. The 5-year overall survival (OS) and event-free survival (EFS) were 60+/-4 and 48+/-4%, respectively. From 1997, timed-sequencing of the LAME SP induction chemotherapy led to an unacceptable frequency of consolidation delay; future improvements are unlikely to come from further increases in intensity. The role of allogenic bone-marrow transplantation from an HLA-identical sibling in CR1 was examined. The disease-free survival (DFS) was 52+/-4% for non-allografted patients and 57+/-7% for allografted patients (P=NS); a better OS for allografted patients was shown and could be related either to allo-BMT early in CR1 or to a second allo-BMT in CR2. For the complete responders after consolidation therapy, the 5-year OS was significantly better in patients randomized for no maintenance therapy (MT-) than in patients randomized for MT (77.6+/-8 vs 59+/-8%; P=0.05), while the 5-year DFS was not significantly different. Exposure to low-dose MT might contribute to clinical drug resistance and treatment failure in relapsing patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos Antineoplásicos/normas , Leucemia Mieloide Aguda/terapia , Adolescente , Trasplante de Médula Ósea , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Estudios de Seguimiento , Francia , Humanos , Lactante , Recién Nacido , Leucemia Mieloide Aguda/mortalidad , Inducción de Remisión , Medición de Riesgo , Análisis de Supervivencia , Resultado del Tratamiento
20.
J Clin Oncol ; 13(4): 902-9, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7707117

RESUMEN

PURPOSE: A phase II study of etoposide (VP-16) and carboplatin was performed in patients with extraocular retinoblastoma to evaluate the response rate with this drug combination. PATIENTS AND METHODS: Twenty patients with extraocular retinoblastoma, age 9 to 120 months, were included in a cooperative multicenter phase II study of the Société Francçaise d'Oncologie Pédiatrique (SFOP). The schedule consisted of consecutive 5-day treatment with VP-16 100 mg/m2/d and carboplatin 160 mg/m2/d. RESULTS: The response rate for the 20 patients was 85%; there were nine complete responses and eight partial responses. Hematologic toxicity was the only serious observed toxicity and was always manageable. CONCLUSION: This combination of VP-16 and carboplatin is highly effective in extraocular retinoblastoma. The high response rate is encouraging for further evaluation of this drug combination in adjuvant chemotherapy when necessary after enucleation or in neoadjuvant chemotherapy for intraocular tumors.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Retinoblastoma/tratamiento farmacológico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/secundario , Carboplatino/administración & dosificación , Preescolar , Etopósido/administración & dosificación , Neoplasias del Ojo/patología , Femenino , Estudios de Seguimiento , Francia , Humanos , Lactante , Masculino , Neoplasias Orbitales/tratamiento farmacológico , Neoplasias Orbitales/secundario , Inducción de Remisión , Retinoblastoma/secundario
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