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1.
Cancer Gene Ther ; 13(3): 298-305, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16110311

RESUMEN

The altered expression of both p53 and erbB2 is strongly related to the disease status and the outcome of bladder cancers. We examined the antitumor efficacy by the modulation of these genetic alterations with a newly designed dual-gene-expressing adenovirus (Ad-p53/erbB2Rz), which expresses p53 and anti-erbB2 ribozyme simultaneously in human bladder cancer cells. Cell growth inhibition efficacy along with biological responses of this virus was compared with other viral vectors (Ad-p53, which expresses wild-type p53 cDNA, and Ad-erbB2Rz, which expresses anti-erbB2 ribozyme, solely or in combination). Sufficient transgene expression in targeted cells and the altered expression of the targeted genes and their encoded proteins were obtained by each therapeutic vector. Each of the three therapeutic viral vectors inhibited bladder cancer cell growth, and the putative additive antitumor effect was shown by the combination of two of the therapeutic vectors. Furthermore, Ad-p53/erbB2Rz had superior therapeutic efficacy when the same titers of viruses were infected. Nonspecific vector-related toxicity was minimized by reducing the total amount of viral titers by using the dual-gene-expressing adenovirus. Modulation of multiple genetic abnormalities might enhance the therapeutic efficacy, and vector-related toxicity could be minimized when the total amount of viral titers are reduced.


Asunto(s)
Adenoviridae/genética , ARN Catalítico/uso terapéutico , Receptor ErbB-2/genética , Proteína p53 Supresora de Tumor/genética , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/terapia , Apoptosis , Supervivencia Celular , Terapia Combinada , Femenino , Técnicas de Transferencia de Gen , Terapia Genética , Vectores Genéticos/uso terapéutico , Humanos , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/metabolismo , Neoplasias de la Vejiga Urinaria/metabolismo
2.
Am J Hematol ; 70(2): 167-73, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12111792

RESUMEN

We report the case of a patient with lymphoma of the salivary gland, at first diagnosed as lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) but later found to infiltrate the bone marrow. At diagnosis, the patient had a polyclonal increase of gamma-globulins. Five years after initial diagnosis, the patient presented with monoclonal gammopathy and infiltration of the bone marrow with neoplastic cells. Initially, the patient had received chemotherapy with different protocols (including etoposide, cyclophosphamide, fludarabin, methotrexate, and vincristine), none of which induced a lasting response. Therapy with rituximab (chimeric anti-CD20 monoclonal antibody) finally led to partial remission. Eighteen months after rituximab, progressive lymphoma in the abdomen and a monoclonal gammopathy developed. The bone marrow showed infiltration by lymphoplasmacytoid cells (monoclonal expression of the light-chain type lambda, positive for CD20, heterogeneous expression of CD45). The patient achieved another short clinical response with 4 cycles of the CHOP-protocol, but soon the lymphoma progressed again. Five years and 8 months after the initial diagnosis, the patient died from septicemia and progressive lymphoma. By polymerase chain reaction (PCR) for the IgH gene it was shown that lymphoma cells were initially oligoclonal in the salivary gland and, later, biclonal in the bone marrow. Sequencing of two bands of apparently same length showed that these manifestations of lymphoma were not identical. Taken together, our data show that the initial low-grade oligoclonal MALT lymphoma was no longer present and a more aggressive biclonal lymphoma with plasmacytoid differentiation had developed. The new lymphoma was clonally distinct and produced high amounts of monoclonal IgG lambda by immunoelectrophoresis. The relationship of the second lymphoma to the initial MALT lymphoma is discussed.


Asunto(s)
Linfoma de Células B de la Zona Marginal/inmunología , Paraproteinemias/etiología , Neoplasias de las Glándulas Salivales/inmunología , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales de Origen Murino , Antígenos CD/análisis , Secuencia de Bases , Médula Ósea/patología , Resultado Fatal , Humanos , Leucemia Linfocítica Crónica de Células B/etiología , Linfoma de Células B de la Zona Marginal/complicaciones , Linfoma de Células B de la Zona Marginal/terapia , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Rituximab , Neoplasias de las Glándulas Salivales/complicaciones , Neoplasias de las Glándulas Salivales/terapia , Glándula Submandibular/patología
3.
Gene Ther ; 7(3): 241-8, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10694801

RESUMEN

HER-2/neu is overexpressed in 25-30% of human breast cancers. We prepared an anti-HER-2/neu hammerhead ribozyme expressed by a recombinant adenovirus (rAdHER-Rz). Human breast cancer cell lines were transduced with high efficiency, resulting in decreased HER-2/neu expression. In vivo injections of rAdHER-Rz into BT-474 tumors established in nude mice inhibited tumor growth to 20% of mock-treated controls. Similar in vivo effects were shown in MCF-7 cells, which do not overexpress HER-2/neu. The growth inhibitory effects of rAdHER-Rz were greater than those of an antisense-expressing vector. These results suggest the utility of anti-HER-2/neu ribozymes as a rational strategy for gene therapy of breast cancer. Gene Therapy (2000) 7, 241-248.


Asunto(s)
Adenoviridae/genética , Neoplasias de la Mama/terapia , Marcación de Gen/métodos , Genes erbB-2/genética , Animales , Secuencia de Bases , Neoplasias de la Mama/patología , División Celular , Humanos , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/métodos , ARN Catalítico/genética , Células Tumorales Cultivadas
4.
Antisense Nucleic Acid Drug Dev ; 9(4): 341-9, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10463078

RESUMEN

Ras oncogenes are thought to play a critical role in cellular proliferation and tumorigenesis. Reversal of the malignant phenotype, inhibition of tumor growth, and decreased tumorgenicity have been demonstrated with the use of anti-H-ras ribozymes. In this study, the therapeutic efficacy of a hammerhead ribozyme targeting the mutated H-ras oncogene was investigated in an experimental bladder cancer model using a recombinant adenovirus as delivery vehicle. Tumors were established in nude mice by subcutaneous injection of EJ human bladder carcinoma cells harboring a point mutation of the H-ras gene. The tumors were treated with intralesional injections of an adenovirus expressing an anti-H-ras ribozyme (rAd-Hras Rz) by different schedules at serial titers, and the tumor inhibition efficacy was analyzed. The viral infection efficacy and kinetics of ribozyme expression were also evaluated. Intralesional injection of rAd-Hras Rz resulted in significant antineoplastic effects in a dose-dependent fashion. Complete regression of the tumor was achieved by rAd-Hras Rz in several cases without recurrence during the 50-day observation period. Although there was moderate vector-associated cytotoxicity in this cell line, complete regressions were not observed in the cases treated with control adenovirus vectors or vectors expressing an inactive anti-H-ras ribozyme or anti-H-ras antisense oligonucleotides. These results suggest the efficacy of a ribozyme-encoding adenovirus in the experimental gene therapy of human bladder cancer.


Asunto(s)
ARN Catalítico/uso terapéutico , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Proteínas ras/antagonistas & inhibidores , Adenoviridae/genética , Animales , Genes ras , Terapia Genética/métodos , Humanos , Ratones , Ratones Desnudos , Células Tumorales Cultivadas , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patología
6.
Pediatr Hematol Oncol ; 14(4): 349-58, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9211539

RESUMEN

Rearrangement of the tal-1 gene is the most frequent clonal marker in childhood T cell acute leukemia. Previously, tal-1 mRNA expression has been observed only in cells of the erythroid, mast cell, and megakaryocytic lineages and in blastic lymphoid cells of normal bone marrow, not in normal lymphocytes or monocytes of the peripheral blood (PB). In this study we addressed the question of tal-1 expression during normal hematopoietic development by performing reverse transcription-polymerase chain reaction (RT-PCR) on RNA from PB cells of 12 healthy donors. Ten of 10 unsorted samples were RT-PCR positive for tal-1 expression. Sorted T cells and monocytes from three donors showed tal-1 RT-PCR products. This is the first direct experimental evidence of tal-1 transcripts in these two normal PB cell types.


Asunto(s)
Proteínas de Unión al ADN/biosíntesis , Reordenamiento Génico , Leucemia-Linfoma de Células T del Adulto/genética , Proteínas Proto-Oncogénicas/biosíntesis , Factores de Transcripción , Transcripción Genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Línea Celular , Niño , Cartilla de ADN , Proteínas de Unión al ADN/genética , Hematopoyesis , Humanos , Leucemia-Linfoma de Células T del Adulto/sangre , Monocitos/metabolismo , Reacción en Cadena de la Polimerasa/métodos , Proteínas Proto-Oncogénicas/genética , Valores de Referencia , Sensibilidad y Especificidad , Proteína 1 de la Leucemia Linfocítica T Aguda , Linfocitos T/metabolismo
7.
Cancer Gene Ther ; 4(2): 84-90, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9080116

RESUMEN

Rearrangement of the gene tal-1 leads to transcriptional dysregulation and contributes to the formation of childhood T-cell acute lymphoblastic leukemia. Therefore, we tried to interfere with the transcription of the SIL/tal-1 fusion gene, the most common form of aberrant tal-1, by treatment with antisense oligodeoxynucleotides (ODNs). The potential of two different strategies was investigated, one targeting the cell line specific SIL/tal-1 fusion region, the other using an ODN complementary to tal-1 sequence downstream of the region not affected by any of the known types of tal-1 rearrangement. With both approaches a single-dose application of 3 mumol of ODN led to a significant antiproliferative effect of a about 25-60% in two T-ALL cell lines characterized by the SIL/tal-1 fusion gene. Investigation of the tal-1 mRNA level by reverse transcription-polymerase chain reaction was in concordance with these results: In both cell lines clearly less of the tal-1-specific fragment was generated after incubation with the antisense ODN tal-1 common than in the control experiments with a mismatched ODN or no ODN at all. Neither the antiproliferation antisense effect nor the downregulation of the steady state tal-1 mRNA level was observed in control cell lines bearing wildtype tal-1.


Asunto(s)
Proteínas de Unión al ADN/genética , Leucemia-Linfoma de Células T del Adulto/tratamiento farmacológico , Leucemia-Linfoma de Células T del Adulto/genética , Oligonucleótidos Antisentido/farmacología , Proteínas de Fusión Oncogénica , Proteínas Proto-Oncogénicas , Factores de Transcripción , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , División Celular/efectos de los fármacos , Proteínas de Unión al ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Péptidos y Proteínas de Señalización Intracelular , Leucemia-Linfoma de Células T del Adulto/patología , Mutación , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/farmacocinética , Proteínas/genética , ARN Mensajero/biosíntesis , ARN Mensajero/efectos de los fármacos , Proteínas Recombinantes de Fusión/genética , Proteína 1 de la Leucemia Linfocítica T Aguda , Células Tumorales Cultivadas
8.
Br J Cancer ; 75(9): 1309-17, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9155051

RESUMEN

The 'deleted in colon carcinoma' (DCC) gene has been considered a candidate tumour-suppressor gene that encodes for a transmembrane protein with strong structural similarity to members of the superfamily of neural cell adhesion molecules. It has been mapped to the chromosomal region 18q21.1 and it is implicated in cellular differentiation and developmental processes. In human osteosarcoma allelic loss frequently occurs on the long arm of chromosome 18, suggesting a possible involvement of the DCC gene in the pathogenesis of this tumour entity. In the present study the mRNA and protein expression and rearrangements at the DNA level of the DCC gene were addressed in 25 osteosarcomas and several tumour cell lines, including osteosarcoma- and colon carcinoma-derived cell lines. Using an reverse transcriptase polymerase chain reach in (RT-PCR)-based approach DCC expression was found to be lost or substantially reduced in 14 of 19 high-grade osteosarcomas, in three of six lower grade osteosarcomas and most of the tumour cell lines, in contrast to normally differentiated osteoblasts. Immunohistochemical studies on DCC protein expression of 14 selected tumours correlated well with the RT-PCR-based results. In view of the putative tumour-suppressor characteristics of the DCC gene its loss or reduction of expression could be a specific event in the development or progression of many high-grade osteosarcomas.


Asunto(s)
Neoplasias Óseas/genética , Deleción Cromosómica , Cromosomas Humanos Par 18/genética , Regulación Neoplásica de la Expresión Génica , Genes DCC/genética , Osteosarcoma/genética , Proteínas Supresoras de Tumor , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Southern Blotting , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Moléculas de Adhesión Celular/biosíntesis , Moléculas de Adhesión Celular/genética , Niño , Receptor DCC , Cartilla de ADN/química , Citometría de Flujo , Genes Supresores de Tumor/genética , Humanos , Persona de Mediana Edad , Osteosarcoma/metabolismo , Osteosarcoma/patología , Reacción en Cadena de la Polimerasa , ARN Mensajero/metabolismo , Receptores de Superficie Celular , Células Tumorales Cultivadas
12.
Science ; 181(4102): 847-9, 1973 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-4125047

RESUMEN

The herbicides atrazine, simazine, monuron, and 2,4-D (2,4-dichlorophenoxyacetic acid) enhanced the toxicity of selected insecticides to Drosophila melanogaster Meigen, Musca domestica L., and larvae of Aedes aegypti L. The insecticides-nine organophosphorus compounds, two chlorinated hydrocarbons, and one carbamate-were used at dosages that resulted in low insect mortalities, while the herbicides by themselves were nontoxic. Atrazine was most effective. With increasing amounts of this herbicide and constant amounts of some insecticides, increasing mortalities of fruit flies were observed. Exposure of the insects for 24 hours to carbofuran (0.5 microgram), p,p'-DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane] (4 micrograms), parathion (0.35 microgram), and diazinon (0.2 microgram) alone resulted in mortalities of 7.5, 9.5, 8, and 10.5 percent, respectively. Based on dosage mortality curves obtained with increasing amounts of atrazine, mortalities of 50 percent of the insect populations would have been achieved with 23, 40, 6, and 10 micrograms of atrazine added to the abovementioned dosages of carbofuran, DDT, parathion, and diazinon, respectively.


Asunto(s)
Herbicidas , Insectos , Insecticidas , Sinergistas de Plaguicidas , Ácido 2,4-Diclorofenoxiacético , Aedes , Animales , Atrazina , Carbofurano , DDT , Dieldrín , Relación Dosis-Respuesta a Droga , Drosophila melanogaster , Fonofos , Moscas Domésticas , Larva , Paraoxon , Paratión , Forato , Pirimidinas , Simazina , Sulfonas , Sulfóxidos
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