Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
1.
Epidemiol Infect ; 147: e109, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30869022

RESUMEN

As part of the evaluation of the French plan for the elimination of measles and rubella, we conducted a seroprevalence survey in 2013, aimed at updating seroprevalence data for people 18-32 years old. A secondary objective was to estimate measles incidence in this population during the 2009-2011 outbreak, and thus estimate the exhaustiveness of measles mandatory reporting. We used a cross-sectional survey design, targeting blood donors 18-32 years old, living in France since 2009, who came to give blood in a blood collecting site. We included 4647 people in metropolitan France, 806 people in Réunion Island and 496 in the French Caribbean. A further 3942 individuals were interviewed in the south-east region of metropolitan France to estimate the exhaustiveness of measles mandatory reporting. One of the main findings of this survey is that the proportion of people 18-32 years old susceptible to both measles and rubella infections remained high in France in 2013, 9.2% and 5.4%, respectively, in metropolitan France, even after the promotion campaigns about vaccination catch-up during and following the major measles epidemic in 2009-2011. Applying our results to French census data would suggest that around 1 million people aged 18-32 years old are currently susceptible to measles in France, despite this age group being one of the vaccination targets of the national measles elimination plan. Another important finding is that only an estimated 45% of the true number of cases in this age group was actually notified, despite notification being mandatory.


Asunto(s)
Donantes de Sangre/estadística & datos numéricos , Brotes de Enfermedades , Sarampión/epidemiología , Rubéola (Sarampión Alemán)/epidemiología , Adulto , Susceptibilidad a Enfermedades/epidemiología , Francia/epidemiología , Humanos , Incidencia , Prevalencia , Estudios Seroepidemiológicos , Adulto Joven
2.
Ann Oncol ; 21(9): 1765-1771, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20233745

RESUMEN

BACKGROUND: We investigated whether circulating tumor cells (CTCs) and circulating endothelial cells (CECs) predict clinical outcome of first-line chemotherapy combined with bevacizumab in metastatic breast cancer patients. PATIENTS AND METHODS: In a French substudy of the MO19391 trial, CTC and CEC counts (CellSearch system) at baseline and changes after two cycles of treatment were correlated with time to progression (TtP). RESULTS: CTC and CEC levels were not correlated in the 67 patients included. At baseline, CTC positivity was a significant prognostic marker for TtP at a threshold of 3 CTC/7.5 ml (P < 0.05) but not at 5 CTC/7.5 ml (P = 0.09). Baseline CEC levels (median 17 CEC/4 ml, range 1-769) were associated with age > or =45 years (P = 0.01), elevated lactate dehydrogenase (P < 0.01) and not with TtP at any threshold. Changes of CTC count during treatment were not a surrogate of TtP, with any of the model tested (threshold based or relative decrease in percent). However, increase in CEC count was associated with improved TtP, at the threshold of 20 CEC/4 ml (P < 0.01). CONCLUSION: Bevacizumab combined with first-line chemotherapy may modify the predictive value of CTC during treatment possibly due to impaired tumor cells intravasation through vessels endothelium. Variations in CEC levels appear to be a promising early surrogate marker of TtP under antiangiogenic treatment.


Asunto(s)
Adenocarcinoma/sangre , Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/sangre , Neoplasias de la Mama/tratamiento farmacológico , Endotelio Vascular/patología , Células Neoplásicas Circulantes/patología , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales Humanizados , Bevacizumab , Ensayos Clínicos Fase III como Asunto , Docetaxel , Endotelio Vascular/efectos de los fármacos , Femenino , Humanos , Persona de Mediana Edad , Metástasis de la Neoplasia , Células Neoplásicas Circulantes/efectos de los fármacos , Paclitaxel/administración & dosificación , Estudios Prospectivos , Tasa de Supervivencia , Taxoides/administración & dosificación , Resultado del Tratamiento
4.
Genes Dev ; 15(11): 1373-82, 2001 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-11390357

RESUMEN

Thrombospondin 1 (TSP1) is a multifunctional protein able to activate TGFbeta and to inhibit angiogenesis in vivo. Although usually thought of as an inhibitor of tumor growth, TSP1 may sometimes be present at high levels during tumor progression, suggesting that tumors can eventually overcome their anti-tumor effects. Using a tet-repressible expression system, we demonstrate that murine TSP1 delayed the onset of tumor growth when produced in the tumor bed by rat fibrosarcoma tumor cells or by stromal fibroblasts coinjected with unmodified C6 glioma tumor cells. Yet upon prolonged exposure to TSP1, tumors came to grow at the same rate in the presence as in the absence of TSP1 and transplantation experiments showed that they had become insensitive to inhibition by TSP1 in both syngeneic and immune compromised hosts. Tumor resistance to TSP1 developed as a result of the in vivo outgrowth of pre-existing tumor cell variants that (1) secreted increased amounts of angiogenic factors that counterbalanced the inhibitory effect of TSP1 on neovascularization and (2) grew more efficiently in the presence of TSP1-activated TGFbeta. These results indicate that prolonged and continuous local delivery of a single multifunctional angiogenesis inhibitor like TSP1 to fast-growing tumors can lead to tumor resistance in vivo by fostering the outgrowth of subpopulations that are a by-product of the genetic instability of the tumor cells themselves.


Asunto(s)
Inhibidores de la Angiogénesis/metabolismo , Neoplasias/metabolismo , Neovascularización Patológica/metabolismo , Trombospondina 1/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Animales , Northern Blotting , Fibrosarcoma/irrigación sanguínea , Fibrosarcoma/metabolismo , Fibrosarcoma/patología , Glioblastoma/irrigación sanguínea , Glioblastoma/metabolismo , Glioblastoma/patología , Immunoblotting , Inmunohistoquímica , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Neoplasias/irrigación sanguínea , Neoplasias/patología , Ratas , Ratas Endogámicas F344 , Células Tumorales Cultivadas
5.
Prostate ; 44(2): 91-103 Jul 1;44(2), 2000 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-10881018

RESUMEN

BACKGROUND: Clinically, the lethal phenotypes of human prostate cancer are characterized by their progression to androgen-independence and their propensity to form osseous metastases. We reported previously on the establishment of androgen-independent (AI) human prostate cancer cell lines derived from androgen-dependent (AD) LNCaP cells, with androgen independence defined as the capability of prostate cancer cells to grow in castrated hosts. One of the sublines, C4-2, was found to be AI, highly tumorigenic, and metastatic, having a proclivity for metastasis to the bone. METHODS: We established the AI and bone metastatic cell sublines B2, B3, B4, and B5 from the parental C4-2 subline, using a previously established coinoculating procedure. We determined the biologic behavior of the parental and derivative LNCaP sublines in vivo and in vitro, as well as their molecular and cytogenetic characteristics. RESULTS: Unlike other human prostate cancer models, the LNCaP progression model shares remarkable similarities with human prostate cancer. We observed a comparable pattern of metastasis from the primary to the lymph node and to the axial skeleton, with a predominant phenotype of osteoblastic reaction; 25-37.5% of the animals developed paraplegia. Cytogenetic and biochemical characterizations of LNCaP sublines also indicate close similarities between human prostate cancer and the LNCaP progression model. Additional chromosomal changes were detected in B2-B5 sublines derived from C4-2 bone metastases. These LNCaP sublines were found to grow faster under anchorage-dependent but not -independent conditions. The in vitro invasion and in vivo metastatic potential of these LNCaP sublines surprisingly correlated with anchorage-dependent and not -independent growth. The derivative LNCaP sublines when cultured in vitro produced a substantially higher (20-30-fold) amount of basal steady-state concentrations of PSA than that of the parental LNCaP cells. PSA production was high initially, but was markedly reduced when the derivative cell lines were inoculated and allowed to grow long-term in vivo for the establishment of tumors and metastasis, suggesting that unknown host factors derived either from the prostate or the bone can effectively downregulate PSA expression by prostate tumor epithelium. CONCLUSIONS: The LNCaP model of human prostate cancer progression will help improve our understanding of the mechanisms of androgen-independence and osseous metastasis, and tumor-host determinants of PSA expression.


Asunto(s)
Neoplasias Óseas/secundario , Modelos Animales de Enfermedad , Osteosarcoma/secundario , Neoplasias de la Próstata/patología , Animales , Northern Blotting , Línea Celular , Dihidrotestosterona/farmacología , Regulación Neoplásica de la Expresión Génica , Violeta de Genciana/química , Histocitoquímica , Humanos , Procesamiento de Imagen Asistido por Computador , Técnicas para Inmunoenzimas , Cariotipificación , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Orquiectomía , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/genética , ARN Neoplásico/química , Organismos Libres de Patógenos Específicos , Células Tumorales Cultivadas
6.
J Histochem Cytochem ; 48(6): 747-54, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10820148

RESUMEN

IGFBP-rP1/mac25 is a recently described member of the insulin-like growth factor binding protein (IGFBP) family. It has structural homology to the other members of the IGFBP family but has a lower affinity for insulin-like growth factors (IGFs). In previous studies using RNA blot hybridization, it was shown that the expression of IGFBP-rP1/mac25 was ubiquitous in normal human tissues. In this report we show by immunohistochemistry that the expression of IGFBP-rP1/mac25 is actually restricted to certain organs and specific cell types. We used an antibody raised against a decapeptide of the C-terminal part of the protein that recognizes a approximately 37-kD protein under reduced conditions. The immunohistochemistry performed on normal human tissues showed a ubiquitous intense staining of peripheral nerves and a variable degree of positive staining in smooth muscle cells, including those from blood vessel walls, gut, bladder, and prostate. Cilia from the respiratory system, epididymis, and fallopian tube showed intense immunoreactivity. Most endothelial cells showed some positivity, whereas fat cells, plasma cells, and lymphocytes were negative. There was specific expression limited to certain cell types in the kidney, adrenal gland, and skeletal muscle, indicating a possible specialized function of IGFBP-rP1/mac25 in these organs. We further noted an opposite pattern of staining in the lining epithelium of breast (typically positive) and prostate glands (largely negative). The specific localization of IGFBP-rP1/mac25 as described implies a function of the protein. However, its regulation within the IGF axis or a possible direct action of IGFBP-rP1/mac25 remains to be demonstrated.


Asunto(s)
Proteínas Portadoras/metabolismo , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina , Anticuerpos/inmunología , Proteínas Portadoras/inmunología , Humanos , Coloración y Etiquetado/métodos , Distribución Tisular , Células Tumorales Cultivadas
7.
Prostate ; 41(3): 190-5, 1999 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-10517877

RESUMEN

BACKGROUND: Three regions of chromosome 13 were previously identified for having loss of heterozygosity (LOH) in human prostate cancer. One of them, at 13q33, was defined by LOH at markers D13S158 and D13S280. The XPG/ERCC5 gene, a DNA repair gene that when mutated in the germline leads to xeroderma pigmentosum, has been mapped to 13q33, within one megabase of D13S158 and D13S280. This paper describes LOH and mutational analysis of the XPG gene in human prostate cancers, in order to determine whether the XPG gene is involved in the development of prostate cancer. METHODS: LOH of the XPG gene was analyzed in 40 primary prostate cancers and 14 metastases by using the microsatellite assay, and its mutations were examined in 5 cell lines, 14 metastases, and 8 tumors with LOH at 13q33 by using the single-strand conformation polymorphism (SSCP)-direct DNA sequencing analysis. RESULTS: Four of the 29 (14%) informative primary tumors and 4 of 8 (50%) metastases showed LOH for the XPG gene. Analysis of the 8 tumors with LOH at the 13q33 region, 14 metastases, and 5 cell lines of prostate cancer revealed two polymorphisms but no mutation of the gene. The polymorphism in exon 2 did not change the amino-acid sequence of the XPG protein, but the exon 15 polymorphism altered codon 1104 from histidine to aspartic acid. The two polymorphisms also occurred in individuals without prostate cancer. CONCLUSIONS: LOH at XPG in prostate cancer supports the conclusion that the 13q33 region contains a gene important in the development of prostate cancer, while lack of mutations of the gene suggests that XPG is not the target gene involved.


Asunto(s)
Cromosomas Humanos Par 13/genética , Reparación del ADN/genética , Proteínas de Unión al ADN/genética , Pérdida de Heterocigocidad , Neoplasias de la Próstata/genética , Adulto , Anciano , Secuencia de Aminoácidos , Análisis Mutacional de ADN , Endonucleasas , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Proteínas Nucleares , Factores de Transcripción
8.
Cancer Res ; 59(12): 2787-90, 1999 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-10383131

RESUMEN

Many of the alterations in the insulin-like growth factor (IGF) axis in prostatic disease have been associated with changes in the insulin-like growth factor binding proteins (IGFBPs), a multigene family of proteins that are thought to mediate the action of IGFs on target tissues. IGFBP-related protein 1 (rP1), also known as IGFBP-7 or mac25, is a recently described member of the IGFBP family, the biological function of which has yet to be completely ascertained. In this study, we analyzed the localization of IGFBP-rP1 in prostate cancer and benign prostate tissues using immunohistochemistry and a polyclonal antibody, T1A12, that is specific for IGFBP-rP1. The most intense staining was observed in nerves, whereas smooth muscle cells in the prostate stained weakly. Lymphocytes were always negative. When normal prostatic secretory epithelium was present, staining was usually absent. The lining secretory epithelium stained positively in 0 of 12 (0%) cases of benign prostatic hyperplasia, 57 of 63 (90.5%) primary adenocarcinomas, and 7 of 7 (100%) prostate cancer metastases. Prostatic intraepithelial neoplasia showed a similar pattern of staining to that observed for the invasive tumors. Analysis of Northern blots showed that none of the prostate cancer cell lines (LNCaP, C4, C4-2, C4-2B4, 9069E3, DU145, and PC3) expressed IGFBP-rP1 mRNA. This lack of expression was confirmed by immunohistochemistry of s.c.-generated tumor xenografts of LNCaP and C4-2 and by immunoblot on serum-free-conditioned media from all prostatic cell lines. In contrast to these results, tumor xenografts generated by direct intraosseous injection of LNCaP or C4-2 to bone marrow space resulted in tumors that stained positively for IGFBP-rP1. Our results show that IGFBP-rP1 is expressed in both in situ and invasive prostate neoplasms, but not typically in normal secretory or BPH epithelium; furthermore, the expression of IGFBP-rP1 can be induced in human prostate cancer cell lines in vivo on interaction with an appropriate host environment.


Asunto(s)
Proteínas Portadoras/biosíntesis , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina , Neoplasias de la Próstata/metabolismo , Proteínas Portadoras/genética , Estudios de Cohortes , Humanos , Inmunohistoquímica , Masculino , Próstata/metabolismo , Neoplasias de la Próstata/patología , ARN Mensajero/biosíntesis , Células Tumorales Cultivadas
9.
Oncogene ; 18(20): 3143-51, 1999 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-10340386

RESUMEN

Thrombospondin 1 (TSP1) is known for its significant anti-angiogenic properties. In a previous study, we have shown that transient or stable overexpression of the transcription factor c-Jun, in rat fibroblasts, leads to repression of TSP1. We now demonstrate that the c-Jun-induced repression of TSP1 does not occur directly and does not require binding of c-Jun to the TSP1 promoter. Instead, repression involves a factor secreted by c-Jun-overexpressing cells. This secreted factor triggers a signal transduction pathway from the membrane to the nucleus, and these signals lead to the binding of the product of the Wilms' tumor suppressor gene, WT1, to the -210 region of the TSP1 promoter. This region binds WT1 and SP1, but not EGR1, although its sequence fits the consensus binding site for this transcription factor. WT1 overexpression in transfected cells inhibits endogenous TSP1 gene expression and TSP1 transcription in experiments using TSP1 promoter-reporter constructs. The WT1 - KTS isoform is more active in repressing TSP1 transcription than WT1 + KTS, while EGR1 is inactive. Enhancement of WT1 binding to DNA in response to c-Jun does not require de novo protein synthesis. The above mechanism for TSP1 repression could apply to other genes, thus coordinating their regulation in the vicinity of a c-Jun-overexpressing cell. We conclude that WT1, which was discovered as a result of its tumor suppressor properties, may also possess oncogenic characteristics in the c-Jun transformation process, and thus repress the anti-angiogenic protein, TSP1.


Asunto(s)
Proteínas de Unión al ADN/genética , Regulación hacia Abajo/genética , Proteínas Proto-Oncogénicas c-jun/genética , Trombospondina 1/genética , Factores de Transcripción/genética , Transcripción Genética/genética , Animales , Línea Celular , Ratones , Regiones Promotoras Genéticas , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Proteínas WT1
10.
Int J Cancer ; 78(1): 112-9, 1998 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-9724102

RESUMEN

The presence of epidermal-growth-factor receptors (EGFR) and of its ligands (TGFalpha and amphiregulin) in breast-cancer tissues suggests that they play a paracrine/autocrine role in tumor growth or progression. This hypothesis was tested on 3 cell lines, S2T2, NS2T2A and NS2T2A1. These epithelial cells are derived from a normal human breast-epithelial-cell culture transformed by SV40-T Ag, are of the same clonal origin, have respectively increasing levels of EGFR, TGFalpha, amphiregulin and of thymidine-kinase activity associated with increasing tumorigenic potential in nude mice (tumor intake and tumor volume). The monoclonal antibody MAb 425, which blocks ligands interaction with EGFR, reduced by more than 90% anchorage-independent growth of the most tumorigenic cells, NS2T2A1. Another anti-EGFR MAb, 528, reduced to 25% of controls the mean tumor mass after NS2T2A1 grafting in mice. Anti-sense RNA expression of EGFR in these cells confirmed the importance of this receptor in tumor progression, since it reduced significantly the tumor volume and tumor weight of NS2T2A1 cells to 16% of those in mock-transfected control cells.


Asunto(s)
Neoplasias de la Mama/etiología , Receptores ErbB/fisiología , Péptidos y Proteínas de Señalización Intercelular , Anfirregulina , Animales , Anticuerpos Monoclonales/farmacología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , División Celular , Línea Celular Transformada , Progresión de la Enfermedad , Familia de Proteínas EGF , Factor de Crecimiento Epidérmico/farmacología , Células Epiteliales/metabolismo , Células Epiteliales/patología , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , Femenino , Glicoproteínas/metabolismo , Sustancias de Crecimiento/metabolismo , Humanos , Ratones , Ratones Desnudos , Trasplante de Neoplasias , ARN sin Sentido/aislamiento & purificación , ARN sin Sentido/farmacología , Factor de Crecimiento Transformador alfa/análisis , Células Tumorales Cultivadas
11.
Breast Cancer Res Treat ; 47(1): 47-55, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9493975

RESUMEN

The role of p53 in modulating apoptosis has suggested that it may affect efficacy of anti cancer agents. For this reason, we have evaluated p53 alterations in 282 consecutive patients with infiltrating node-negative breast cancer who underwent primary surgery and were randomized either to CMF (Cyclophosphamide 400 mg/m2, Fluorouracil 400 mg/m2, and Methotrexate 40 mg/m2) or control arm (no adjuvant therapy) from 1980 to 1989. p53 alterations were analyzed by immunohistochemistry using DO7 MoAb, revealed by immunoperoxidase technique, and quantitated in term of percentage of positive cells. We observed a positive staining in 24% of the tumors. Among them, 10% had a positive staining in more than 75% of the cells. There was a highly significant association between the proportion of positive cells and histologic grade of the infiltrating ductal carcinomas (p<0.004). However, there was no association with age, tumor size, hormone receptor content, or vascular embolism. There was a trend but no significant relationship between positive staining and overall survival either in each arm of the trial or in the overall population. Interestingly, we observed a higher relative risk of local relapse after conservative therapy in the boosted area in the group of mutated p53 (RR=4.41; p<0.0005). We conclude that, in this node-negative breast tumor population, alteration of p53 cannot predict the response to the chemotherapy. However, it may represent a useful marker of risk of local relapse and of radio resistance.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Proteína p53 Supresora de Tumor/análisis , Adulto , Anciano , Neoplasias de la Mama/química , Ciclofosfamida/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Humanos , Metástasis Linfática , Metotrexato/administración & dosificación , Persona de Mediana Edad
12.
Int J Cancer ; 71(1): 42-8, 1997 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-9096664

RESUMEN

Stromal and epithelial components surrounding neoplastic cells are believed to be important in tumor regulation. We have studied the effects of stromal and epithelial cells on the proliferation of a variety of breast-cancer epithelial cell lines. Co-culture experiments were performed in which the 2 cell types were separated by a microporous membrane. Under these conditions, fibroblasts from normal breast tissues inhibited the proliferation of MCF-7 cells, but not that of immortalized normal S2T2 cells. In contrast, fibroblasts from cancerous breast tissues did not influence the proliferation of the 2 cell lines tested. Conditioned media (CM) of breast fibroblasts derived from normal tissues were not able to affect MCF-7 cell growth, suggesting complex paracrine interactions between both cell types. Normal breast epithelial cells (NBEC) have also been tested for their ability to regulate the proliferation of breast-cancer epithelial cell lines. Co-culture experiments demonstrated that NBEC inhibited a variety of breast-cancer cell lines. CM from NBEC induced similar results and the inhibitory effect appeared to be specific for epithelial cells from tumorous breast. Moreover, CM from NBEC and normal fibroblasts were shown to contain more TGF beta 1 and amphiregulin than those of MCF-7 cells. We conclude that both the tissue origin and the target tumor cell's phenotype will determine the extent of proliferative response. More important, the tumor-cell growth inhibition induced by fibroblasts and epithelial cells of normal breast tissue may constitute a tumor-growth-regulatory mechanism.


Asunto(s)
Neoplasias de la Mama/patología , Mama/citología , División Celular/fisiología , Péptidos y Proteínas de Señalización Intercelular , Actinas/análisis , Anfirregulina , Antineoplásicos/metabolismo , Mama/química , Mama/efectos de los fármacos , Mama/metabolismo , Neoplasias de la Mama/química , Neoplasias de la Mama/metabolismo , Proteínas de Unión al Calcio/análisis , División Celular/efectos de los fármacos , Técnicas de Cocultivo/métodos , Medios de Cultivo Condicionados/farmacología , Relación Dosis-Respuesta a Droga , Familia de Proteínas EGF , Células Epiteliales , Epitelio/química , Epitelio/efectos de los fármacos , Epitelio/metabolismo , Femenino , Fibroblastos/fisiología , Glicoproteínas/metabolismo , Inhibidores de Crecimiento/biosíntesis , Inhibidores de Crecimiento/metabolismo , Inhibidores de Crecimiento/farmacología , Sustancias de Crecimiento/metabolismo , Humanos , Proteínas de Microfilamentos/análisis , Péptidos/metabolismo , Células del Estroma/química , Células del Estroma/efectos de los fármacos , Células del Estroma/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Células Tumorales Cultivadas , Calponinas
13.
Cancer Detect Prev ; 21(1): 62-70, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9043765

RESUMEN

Somatostatin (SS) can inhibit growth hormone (GH) secretion from the pituitary and tumor cell proliferation via membrane-bound receptors (SST). Five SST subtypes have been cloned and can be discriminated by specific peptides. In order to evaluate the human tissue distribution of the SSTs, we first used the cross-linking assay with the 125I-SS-14. A cross-linked complex of 57 kDa was detected in a majority (76%) of the surgical biopsies of normal and tumoral tissues examined (N = 222) and in all tested cell lines (N = 20). However, in regard to the organs, the incidence varied from 33% (epiploon metastases) to 100% (colorectal adenocarcinoma, prostate). Additional, minor SS-14 cross-linked complexes were detected in a few samples, suggesting the simultaneous existence of other SST subtypes. In tumor cell lines, the 57-kDa complex was reduced by the SST2-selective SS analogs BIM23014, BIM23060, and BIM23068, and by SS-14 but not by the non-SST2-selective BIM23052 and BIM23056. Its pharmacological profile therefore corresponded to SST2. Northern blot analysis showed one 2.5-kb human SST2 mRNA in these cell lines. We demonstrate that SST2 is detectable in normal and tumoral human tissues and thus represents an SST subtype target for the development of more specific SS analogs.


Asunto(s)
Neoplasias/ultraestructura , Receptores de Somatostatina/metabolismo , Biopsia , Reactivos de Enlaces Cruzados/metabolismo , Humanos , ARN/metabolismo , ARN Mensajero/metabolismo , ARN Neoplásico/metabolismo , Ensayo de Unión Radioligante , Somatostatina/análogos & derivados , Somatostatina/metabolismo , Distribución Tisular , Células Tumorales Cultivadas
14.
Int J Cancer ; 68(2): 207-14, 1996 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-8900430

RESUMEN

To understand specific interactions between stromal cells and epithelial cells in benign prostatic hyperplasia (BPH) and prostatic adenocarcinoma, we developed stromal-cell cultures from normal human prostate (PNX) and BPH (BH101), composed of fibroblasts and myofibroblasts. Their role in epithelial-cell growth was studied using the established cancer cell lines LNCaP, PC3 and DU145 and an SV40 large T-immortalized normal epithelial-cell line, PNT1A, in double-diffusion co-culture chambers. PNT1A was stimulated by PNX (x1.6) and more strongly by BH101 stromal cells (x2.7). Conversely, LNCaP growth decreased by 50% in the presence of BH101 stromal cells (stromal/epithelial ratio: 10). A BH101-conditioned medium (CM), obtained in serum-free conditions, induced 90% inhibition of [3H]thymidine incorporation of the LNCaP androgen-sensitive cell line. Two other androgen-independent prostate cancer cell lines were either insensitive to BH101 CM (PC3) or slightly inhibited (40% for DU145). BH101 produced large amounts of IL-1beta, IL-6 and IL-8. HPLC gel filtration enabled separation of an inhibitory fraction which contained IL-6. IL-6 was demonstrated to be responsible for the strong inhibitory effect since an IL-6-neutralizing antibody abolished this inhibition, which was reproduced by human recombinant IL-6. Recombinant IL-6 growth inhibition was observed only on LNCaP prostate cancer androgen-sensitive cells.


Asunto(s)
ADN de Neoplasias/biosíntesis , Inhibidores de Crecimiento/metabolismo , Hiperplasia Prostática/metabolismo , Neoplasias de la Próstata/patología , Adulto , Comunicación Celular , División Celular , Cromatografía Líquida de Alta Presión , Técnicas de Cocultivo , ADN de Neoplasias/efectos de los fármacos , Humanos , Interleucina-6/farmacología , Masculino , Hiperplasia Prostática/patología , Neoplasias de la Próstata/metabolismo , Células del Estroma/metabolismo , Células del Estroma/patología , Células Tumorales Cultivadas
15.
Cancer Res ; 56(15): 3461-7, 1996 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-8758912

RESUMEN

Proton nuclear magnetic resonance spectroscopy was performed on whole cells to study lipids and metabolites in Adriamycin- and Taxol-resistant K562 cells expressing multidrug resistance (MDR) and their sensitive counterparts. With one-dimensional spectra, both resistant cell lines showed lower fatty acid methylene:methyl ratios and higher choline:methyl ratios than sensitive cells. Using two-dimensional COSY spectra, a decrease in the glutamine content was evidenced in resistant cells. When these cells were maintained in culture medium without the drug, the fatty acid signals were partially recovered. Adriamycin-resistant K562 cells were also treated for 4 days with a high dose of verapamil, a MDR-reversing agent. The nuclear magnetic resonance spectra of verapamil-treated cells also showed partial recovery of fatty acid signals. These results could be paralleled with the reversion of the resistant phenotype, as evidenced by measuring the inhibiting concentration of Adriamycin and vinblastine in K562adr cells cultured without the drug or after short-term exposure to verapamil. Conversely, P-glycoprotein and mRNA expression and DNA amplification of the mdr gene were not modified when compared to resistant cells, suggesting that the MDR phenotype could be partially reversed independently of the mdr gene amplification and expression. These results demonstrate the role of lipids in the resistance phenomenon.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Antineoplásicos Fitogénicos/farmacología , Doxorrubicina/farmacología , Resistencia a Múltiples Medicamentos/fisiología , Leucemia Experimental/tratamiento farmacológico , Leucemia Experimental/metabolismo , Lípidos/análisis , Paclitaxel/farmacología , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/biosíntesis , ADN de Neoplasias/genética , Resistencia a Antineoplásicos , Amplificación de Genes , Expresión Génica , Humanos , Espectroscopía de Resonancia Magnética/métodos , ARN Mensajero/genética , Células Tumorales Cultivadas , Vinblastina/farmacología
18.
Int J Cancer ; 62(6): 724-31, 1995 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-7558421

RESUMEN

To develop an experimental prostate cancer model, we immortalized normal human prostate adult epithelial cells with SV40 large-T antigen. Two sublines were derived in culture, namely PNT1A and PNT1B. They retained the characteristics of prostate epithelial cells, but did not clone in soft agarose. PNT1A occasionally formed undifferentiated adenocarcinoma tumors in nude mice, but only in the presence of matrigel. PNT1A and PNT1B displayed common cytogenetic alterations: a 10q arm deletion, which is a recurrent alteration in prostate carcinoma, chromosome losses and a translocation involving chromosome 5. An extensive study of oncogenic alterations occurring in these cells showed that PNT1A displayed c-myc gene amplification, forming an hsr on chromosome 4, as well as gene amplification, forming an hsr on chromosome 4, as well as c-myc mRNA overexpression, with a faster doubling time (25 hr); moreover, it seemed less sensitive to EGF than PNT1B. PNT1B had a doubling time identical to that of normal cells (48 hr) but displayed EGF receptor gene amplification accompanied by an increased number of EGF binding sites and sensitivity to EGF. Because both cell lines displayed cytogenetic and oncogenic alterations found in prostate cancer, as well as differing malignant potentials, they represent an interesting model for studying the progression of prostate tumors.


Asunto(s)
Transformación Celular Viral , Receptores ErbB/genética , Amplificación de Genes , Genes myc , Neoplasias de la Próstata/genética , Adulto , Animales , Secuencia de Bases , División Celular/fisiología , Epitelio/patología , Humanos , Cariotipificación , Masculino , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Trasplante de Neoplasias , Fenotipo , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/ultraestructura , Virus 40 de los Simios , Células Tumorales Cultivadas
19.
Mol Cell Endocrinol ; 113(2): 195-204, 1995 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-8674827

RESUMEN

We investigated somatostatin receptors (SSTRs) in surgical specimens of prostate cancer and benign prostate hyperplasia (BPH), a normal immortalized epithelial cell line (PNT1), epithelial cancer cell lines, and stromal cells in short-term culture derived from normal and BPH biopsies. Cross-linking studies with 125I-Tyr11-SRIF-14 (125I-SRIF) and the SRIF analog 125I-BIM-23104 identified one major 57-kDa band both in surgical specimens and in epithelial and stromal cells cultures. In membrane-enriched fractions and whole stromal cells from a normal prostate and from one BPH, a single type of SSTR was characterized (Kd = 6.10(-9) and 10(-8) M, respectively, Bmax = 1.6 pmol per mg of proteins). mRNA for SSTR1 was detected in all epithelial and stromal cells tested except for PNT1, while SSTR2 mRNA was detected in one BPH stromal cell culture. BIM-23104 had no effect on the in vitro growth of the epithelial cells tested. Conversely, 10(-10) M BIM-23104 induced >50% growth inhibition of stromal cells after 6 days in culture. These results may have implications for therapeutic strategies using SRIF analogs in BPH and prostate cancer.


Asunto(s)
Antineoplásicos/farmacología , Péptidos Cíclicos/farmacología , Próstata/metabolismo , Receptores de Somatostatina/metabolismo , Somatostatina/análogos & derivados , Secuencia de Aminoácidos , Línea Celular , Células Cultivadas , Reactivos de Enlaces Cruzados , Epitelio/metabolismo , Expresión Génica , Humanos , Radioisótopos de Yodo , Masculino , Datos de Secuencia Molecular , Próstata/patología , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/patología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Receptores de Somatostatina/genética , Somatostatina/metabolismo , Somatostatina/farmacología , Células del Estroma/metabolismo , Células Tumorales Cultivadas
20.
Biol Cell ; 84(3): 187-93, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8720439

RESUMEN

Thirty endometrial biopsies were cultured in order to separate stromal and epithelial cells. Using epidermal growth factor (EGF), cortisol, cholera toxin, insulin with 5% horse serum for epithelial cells or a medium with 20% fetal calf serum for stromal cells, we could specifically enrich endometrial culture in epithelial or stromal cells and culture them for 1 or 2 months. These cultures retained the phenotypic characteristics of epithelial (cytokeratins, mucin HMFG 1) and stromal (vimentin, smooth muscle actin, desmin) lineage by immunostaining analysis. Epithelial and stromal cultures from one individual were respectively immortalized by the SV 40 large T antigen. The immortalized cell lines kept the phenotype of the normal cells from which they derived.


Asunto(s)
Antígenos Transformadores de Poliomavirus/biosíntesis , Transformación Celular Viral , Endometrio/citología , Virus 40 de los Simios/genética , Actinas/análisis , Adolescente , Adulto , Biomarcadores/análisis , División Celular , Línea Celular Transformada , Separación Celular , Células Cultivadas , Desmina/análisis , Endometrio/patología , Células Epiteliales , Epitelio/patología , Femenino , Sustancias de Crecimiento/farmacología , Humanos , Inmunohistoquímica , Queratinas/análisis , Ciclo Menstrual , Persona de Mediana Edad , Mucinas/análisis , Fenotipo , Proteínas Recombinantes/biosíntesis , Transfección , Enfermedades Uterinas/patología , Enfermedades Uterinas/cirugía , Vimentina/análisis
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA