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1.
J Exp Med ; 154(5): 1403-18, 1981 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-6975346

RESUMEN

Three cell lines of mature T cell origin derived from patients with cutaneous T cell lymphoma-leukemias (CTCL) were found to be constitutive producers of T cell growth factor (L-TCGF). These are the first reported human cell lines which constitutively produce TCGF. Biologically active TCGF could also be eluted from the surface of these cells using an acid glycine buffer under conditions that maintained cell viability, and subcellular fractionation showed that almost all the TCGF activity was associated with the plasma membrane. Over 30 other human hematopoietic cell lines derived from other disorders were unable to produce TCGF even after induction, and their acid eluates did not contain TCGF activity. L-TCGF from CTCL lines had the same biological activity as TCGF obtained from normal leukocytes (N-TCGF) in that they both supported the long-term growth of normal T cells only after the cells were previously activated by antigen or lectin. Both L-TCGF and N-TCGF increased the rate of proliferation of TCGF-independent and TCGF-dependent CTCL cell lines. The same three factor-independent cell lines that released TCGF adsorbed TCGF in a cell-concentration, time-, and temperature-dependent manner. Since the CTCL cell lines produce TCGF, adsorb TCGF, and increase their proliferative rate in response to TCGF or a related molecule, it is suggested that this endogenously produced factor plays a role in maintaining the abnormal proliferation of these cells in culture as permanently growing cell lines independent of exogenous TCGF. However, this does not mean that this is an essential aspect of neoplastic transformation. Since it is unusual to develop these cell lines in the absence of the continuous need for added TCGF, "autostimulation" may be one of the many unusual variant phenotypic properties sometimes associated with neoplastic cells that gives them a selective advantage for in vitro growth.


Asunto(s)
Leucemia Experimental/inmunología , Linfoma/inmunología , Neoplasias Cutáneas/inmunología , Linfocitos T/inmunología , Adsorción , Animales , Línea Celular , Transformación Celular Neoplásica , Humanos , Interleucina-2/biosíntesis , Interleucina-2/farmacología , Activación de Linfocitos
2.
J Exp Med ; 134(3): 52-64, 1971 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-19867381

RESUMEN

The development of autoimmunity in New Zealand mice is related to genetic, immunologic, and viral factors. Evidence is presented to suggest that thymus-dependent immune functions may be depressed and bone marrow-dependent functions augmented in these mice. Antibodies to RNA and DNA appear spontaneously and can also be induced by treatment with rI.rC. Antibodies binding rI.rC-(14)C in human lupus sera, in NZB/NZW F(1) (B/W) mice developing lupus, and in NZB, ALN, and ALN/NZB mice have greatest specificity for reovirus double-stranded RNA. Treatment of B/W mice with RNA and cyclophosphamide induces immunologic tolerance, and suppresses antibodies binding rI.rC-(14)C. During recovery, the specificity of the antibodies is unaltered. Induction of tolerance in this way prevents the accelerated formation of anti-RNA antibodies normally induced by MLV. This finding suggests that virus-accelerated and natural disease occur through a similar mechanism, and supports the hypothesis that viruses may act as antigenic stimuli for a genetically hyper-responsive antibody-producing system.

3.
J Exp Med ; 161(5): 1135-51, 1985 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-2580935

RESUMEN

We have found markedly deficient expression of the class I major histocompatibility antigens HLA-A,B,C and beta 2m on human small-cell lung cancer (SCLC) lines and fresh tumor samples. The deficit of HLA-A,B,C and beta 2-microglobulin (beta 2m) antigen expression was demonstrated with both radiobinding assays and indirect immunofluorescence assays. Immunoprecipitation of metabolically labeled cells with antibodies to class I antigens showed most SCLC lines to have synthesized almost no beta 2m and HLA-A,B,C proteins. Northern blot analysis, using human HLA-A,B, and beta 2m cDNA probes, showed that almost all SCLC lines tested had markedly decreased amounts of HLA and beta 2m mRNA, but both gene products could be induced with interferon treatment of SCLC lines. We conclude that human SCLC, in contrast to other lung cancer types, is characterized by greatly reduced transcription of HLA-A,B,C and beta 2m genes, which suggests the existence of a mechanism for evading the host immune response to the tumor and of an E1a-like product in this type of tumor cell.


Asunto(s)
Carcinoma de Células Pequeñas/inmunología , Antígenos HLA/análisis , Neoplasias Pulmonares/inmunología , ARN Mensajero/biosíntesis , Microglobulina beta-2/inmunología , Antígenos de Superficie/análisis , Carcinoma de Células Pequeñas/genética , Carcinoma de Células Pequeñas/metabolismo , Línea Celular , Genes MHC Clase II , Antígenos HLA/biosíntesis , Antígenos HLA/genética , Antígenos HLA-A , Antígenos HLA-B , Antígenos HLA-C , Humanos , Interferones/farmacología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Microglobulina beta-2/biosíntesis , Microglobulina beta-2/genética
4.
Ann Oncol ; 21 Suppl 7: vii225-9, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20943619

RESUMEN

Until recently the major clinical question was 'Is it small-cell or non small-cell cancer'. However, advances in conventional and targeted therapy have completely changed the landscape. Identification of the major non-small-cell lung cancer (NSCLC) types (adenocarcinoma and squamous carcinoma) are important for a number of predictive and prognostic reasons, including pemetrexed treatment, anti-angiogenic therapy and administration of tyrosine kinase inhibitors. Fortunately, advances in pathology of lung cancer have kept abreast, with newer, simplified methods to identify the major NSCLC types in small diagnostic samples, and modifications of the pathological classification of adenocarcinomas reflecting changing clinical and molecular concepts. For the patient to obtain maximum benefit from the recent developments in therapeutics, a multidisciplinary approach is required with co-operation between oncologists, surgeons, radiologists and pathologists.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/clasificación , Neoplasias Pulmonares/clasificación , Terminología como Asunto , Adenocarcinoma/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/terapia , Carcinoma de Células Escamosas/diagnóstico , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/terapia , Técnicas de Diagnóstico Molecular , Mutación/fisiología
6.
Science ; 214(4526): 1246-8, 1981 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-6272398

RESUMEN

"Small cells" or "oat cells" characterize a virulent form of lung cancer and share many biochemical properties with peptide-secreting neurones. The neuropeptide bombesin is present in all small-cell lines examined, but not in other lung cancer cell lines, suggesting that bombesinergic precursor cells in lung may give rise to this disease.


Asunto(s)
Bombesina/análisis , Carcinoma de Células Pequeñas/análisis , Neoplasias Pulmonares/análisis , Péptidos/análisis , Adenocarcinoma/análisis , Carcinoma de Células Escamosas/análisis , Línea Celular , Humanos , Mesotelioma/análisis
7.
Science ; 241(4863): 353-7, 1988 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-2838909

RESUMEN

Small cell lung cancer (SCLC) has been associated with loss of heterozygosity at several distinct genetic loci including chromosomes 3p, 13q, and 17p. To determine whether the retinoblastoma gene (Rb) localized at 13q14, might be the target of recessive mutations in lung cancer, eight primary SCLC tumors and 50 cell lines representing all major histologic types of lung cancer were examined with the Rb complementary DNA probe. Structural abnormalities within the Rb gene were observed in 1/8 (13%) primary SCLC tumors, 4/22 (18%) SCLC lines, and 1/4 (25%) pulmonary carcinoid lines (comparable to the 20 to 40% observed in retinoblastoma), but were not detected in other major types of lung cancer. Rb messenger RNA expression was absent in 60% of the SCLC lines and 75% of pulmonary carcinoid lines, including all samples with DNA abnormalities. In contrast, Rb transcripts were found in 90% of non-SCLC lung cancer lines and in normal human lung. The finding of abnormalities of the Rb gene in SCLC and pulmonary carcinoids (both neuroendocrine tumors) suggests that this gene may be involved in the pathogenesis of a common adult malignancy.


Asunto(s)
Carcinoma de Células Pequeñas/genética , Cromosomas Humanos Par 13 , Neoplasias Pulmonares/genética , Retinoblastoma/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Deleción Cromosómica , ADN de Neoplasias/genética , Humanos , ARN Mensajero/genética , ARN Neoplásico/genética , Células Tumorales Cultivadas
8.
Science ; 282(5387): 284-7, 1998 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-9765152

RESUMEN

The PPP2R1B gene, which encodes the beta isoform of the A subunit of the serine/threonine protein phosphatase 2A (PP2A), was identified as a putative human tumor suppressor gene. Sequencing of the PPP2R1B gene, located on human chromosome 11q22-24, revealed somatic alterations in 15% (5 out of 33) of primary lung tumors, 6% (4 out of 70) of lung tumor-derived cell lines, and 15% (2 out of 13) of primary colon tumors. One deletion mutation generated a truncated PP2A-Abeta protein that was unable to bind to the catalytic subunit of the PP2A holoenzyme. The PP2R1B gene product may suppress tumor development through its role in cell cycle regulation and cellular growth control.


Asunto(s)
Neoplasias del Colon/genética , Genes Supresores de Tumor , Neoplasias Pulmonares/genética , Fosfoproteínas Fosfatasas/genética , Secuencia de Aminoácidos , Ciclo Celular , División Celular , Mapeo Cromosómico , Cromosomas Humanos Par 11/genética , Neoplasias del Colon/enzimología , Mutación del Sistema de Lectura , Humanos , Pérdida de Heterocigocidad , Neoplasias Pulmonares/enzimología , Datos de Secuencia Molecular , Fosfoproteínas Fosfatasas/química , Fosfoproteínas Fosfatasas/metabolismo , Mutación Puntual , Proteína Fosfatasa 2 , Eliminación de Secuencia , Células Tumorales Cultivadas
9.
Science ; 215(4529): 181-2, 1982 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-6274023

RESUMEN

A specific, acquired chromosomal abnormality (deletion 3p) has been found in at least one chromosome 3 in 100 percent of the metaphases in 12 of 12 cell lines cultured from human small-cell lung cancer tissue and in 2-day tumor culture specimens from three patients. Analysis of the shortest region of overlap shows the deletion to be 3p(14-23). This specific change was not seen in five of five lung cancer cell lines other than small-cell lung cancer or in two lymphoblastoid lines cultured from cells of small-cell lung cancer patients whose tumors had the 3p deletion.


Asunto(s)
Carcinoma de Células Pequeñas/genética , Deleción Cromosómica , Neoplasias Pulmonares/genética , Células Cultivadas , Cromosomas Humanos 1-3 , Humanos , Cariotipificación
10.
Science ; 222(4622): 385-9, 1983 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-6194563

RESUMEN

A protoplast fusion method was developed to stably transfect human cells with pSV2-derived plasmids at frequencies greater than 10(-3). This procedure made it possible to test the biological effect of a hepatitis B virus (HBV) gene independent of the viral structures required for infection. A pSV2gpt+ plasmid constructed to carry a subgenomic fragment of HBV that contained the core antigen gene (HBc gene) was transfected into human cells. A human epithelial cell line was stably transfected with the HBc+ gene by selecting recipient cells for expression of guanine phosphoribosyl transferase expression. With this gpt+/HBc+ cell line it was shown that growth in serum-free medium or treatment with 5'-azacytidine stimulates the production of the HBV core antigen. A hepatocellular carcinoma carrying the entire HBV genome was stimulated to produce the HBc gene product in response to the same factors that stimulated HBcAg production in the gpt+/HBc+ cell line constructed by transfection. The temporal relation between the cytopathologic response and HBc gene expression was similar for both cell types, indicating a primary role for HBc gene expression in the cytopathology of HBV-infected human liver.


Asunto(s)
Transformación Celular Viral , Antígenos del Núcleo de la Hepatitis B/genética , Azacitidina/farmacología , Fusión Celular , Células Cultivadas , Efecto Citopatogénico Viral , Regulación de la Expresión Génica/efectos de los fármacos , Genes Virales , Humanos , Transfección
11.
Science ; 246(4929): 491-4, 1989 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-2554494

RESUMEN

Allele loss is a hallmark of chromosome regions harboring recessive oncogenes. Lung cancer frequently demonstrates loss of heterozygosity on 17p. Recent evidence suggests that the p53 gene located on 17p13 has many features of such an antioncogene. The p53 gene was frequently mutated or inactivated in all types of human lung cancer. The genetic abnormalities of p53 include gross changes such as homozygous deletions and abnormally sized messenger RNAs along with a variety of point or small mutations, which map to the p53 open reading frame and change amino acid sequence in a region highly conserved between mouse and man. In addition, very low or absent expression of p53 messenger RNA in lung cancer cell lines compared to normal lung was seen. These findings, coupled with the previous demonstration of 17p allele loss in lung cancer, strongly implicate p53 as an anti-oncogene whose disruption is involved in the pathogenesis of human lung cancer.


Asunto(s)
Neoplasias Pulmonares/genética , Proteínas Oncogénicas/genética , Fosfoproteínas/genética , Secuencia de Bases , Tumor Carcinoide/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Células Pequeñas/genética , Cromosomas Humanos Par 17 , ADN de Neoplasias/genética , Amplificación de Genes , Humanos , Mutación , ARN Mensajero/genética , ARN Neoplásico/genética , Ribonucleasas , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor
12.
J Clin Invest ; 83(6): 2120-4, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2542383

RESUMEN

A deletion involving chromosome 3p (14-23) characteristically occurs in small cell lung cancer (SCLC). Reduction to homozygosity, rather than complete loss, is typically observed for genes in the deleted region. Lack of expression for genes encoded by this region, implying inactivation of all alleles, has not been previously described. We have examined the expression of aminoacylase-1 (ACY-1), encoded by chromosome 3p21, using both an electrophoretic activity assay and a monoclonal antibody-based ELISA. A variety of human tissues, including lung, brain, liver, kidney, heart, adrenal medulla, and erythrocytes have previously been tested for ACY-1 activity and antigen; all but erythrocytes are positive. Thus, ACY-1 is expressed in all nucleated human cells examined to date. ACY-1 was undetectable in a significant number of SCLC cell lines (4/29) and tumors (1/8), but not in non-small cell lung cancer (NSCLC) cell lines (0/19) or tumors (0/9), nor in a variety of other human cell lines (0/15) or colon tumors (0/8). In addition, reduced (approximately 10% of normal) ACY-1 expression was common in SCLC cell lines (14/29) and tumors (3/8), but not in NSCLC cell lines (1/19) or tumors (0/9), nor in other human cell lines (0/15) or colon tumors (0/8). Thus, low or undetectable ACY-1 expression is highly specific for SCLC and occurs in both cell lines and tumor tissue. The finding of undetectable ACY-1 expression in SCLC supports the hypothesis that inactivation of all alleles of specific chromosome 3p genes occurs in a SCLC in a fashion analogous to Rb gene inactivation in retinoblastoma, and suggests that the structural gene for ACY-1 may be closely linked to a putative SCLC tumor suppressor gene.


Asunto(s)
Amidohidrolasas/metabolismo , Carcinoma de Células Pequeñas/enzimología , Deleción Cromosómica , Cromosomas Humanos Par 3 , Regulación de la Expresión Génica , Neoplasias Pulmonares/enzimología , Amidohidrolasas/genética , Carcinoma de Células Pequeñas/genética , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Humanos , Neoplasias Pulmonares/genética , Células Tumorales Cultivadas/enzimología
13.
J Clin Invest ; 65(6): 1440-8, 1980 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6997334

RESUMEN

Flow cytometric (FCM) analysis of DNA content was performed on 82 lymph node and peripheral blood specimens from 46 patients with mycosis fungoides and the Sézary syndrome. Overall, 32 of the 46 patients (70%) had aneuploidy detected by FCM. Aneuploidy was present in 63% of the patients at the time of diagnosis before systemic therapy. In these patients, aneuploidy was frequently detected in blood and lymph node specimens scored as negative by cytology and histology, suggesting that unsuspected extracutaneous dissemination is present in many patients at the time of diagnosis. Direct comparison with Giemsa-banded cytogenetic studies showed an excellent correlation of FCM results and cytogenetic chromosome number. However, FCM frequently detected a larger fraction of aneuploid cells, and mitogen-stimulation studies suggest this is the result of preferential stimulation of normal lymphocytes by phytohemagglutinin. Thus, mitogens with a preference for malignant T cells, such as staphylococcal protein A, should be used for cytogenetic analysis of malignant T-cell disorders. At diagnosis, some histologically positive specimens contained only diploid cells by FCM and cytogenetic analysis. These patients had a more indolent clinical course than patients with aneuploidy. Aneuploidy was detected by FCM as either wide G(1) or as discrete aneuploid peaks. The presence of aneuploidy at any time in the clinical course implied a poor prognosis. Discrete hyperdiploid peaks were associated with large cell histology, early relapse, and aggressive clinical course. The development of hyperdiploidy at relapse was documented in four patients and was associated with a transition to large cell histology and a poor prognosis. Similar studies may elucidate differences in natural history and mechanism for transition in histology in other lymphomas and solid tumors.


Asunto(s)
ADN/metabolismo , Micosis Fungoide/metabolismo , Síndrome de Sézary/metabolismo , Linfocitos T/metabolismo , Bandeo Cromosómico , Cromosomas Humanos/ultraestructura , Técnicas Citológicas , Densitometría/métodos , Humanos , Cariotipificación , Ganglios Linfáticos/metabolismo , Linfocitos T/ultraestructura
14.
J Clin Invest ; 79(5): 1412-20, 1987 May.
Artículo en Inglés | MEDLINE | ID: mdl-2883200

RESUMEN

Using a small cell lung cancer (SCLC) cDNA library, we obtained clones for the creatine kinase-B (CK-B) gene and determined the nucleotide sequence for the protein coding and 3' untranslated region (3' UT). The human translated protein spans 381 residues and the amino acid homology with rabbit CK-B is greater than 98%. We have demonstrated that a nucleic acid probe encompassing the protein coding region will also hybridize to CK-M sequences while a probe derived from the 3' UT region is CK-B specific. When a B-isoenzyme specific sequence is hybridized to Eco RI cut genomic DNA, two independent restriction fragment polymorphisms are detected. We have subsequently localized these two CK-B homologous sequences to chromosomes 14q32 and 16. Finally, we show that increased levels of CK-B seen in SCLC are not accompanied by gene amplification or rearrangement, but reflect a greatly enhanced level of CK-B specific mRNA that is not seen in non-SCLC lines thus far examined.


Asunto(s)
Creatina Quinasa/genética , ADN/análisis , Desoxirribonucleasas de Localización Especificada Tipo II , Regulación de la Expresión Génica , Neoplasias Pulmonares/genética , Secuencia de Aminoácidos , Secuencia de Bases , Carcinoma de Células Pequeñas/genética , Línea Celular , Mapeo Cromosómico , Enzimas de Restricción del ADN/metabolismo , Desoxirribonucleasa BamHI , Desoxirribonucleasa HindIII , Humanos , Isoenzimas , Polimorfismo de Longitud del Fragmento de Restricción , Ribonucleasas/metabolismo
15.
J Clin Invest ; 82(2): 502-7, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2900253

RESUMEN

Previous karyotypic analysis of human small cell lung cancer cell lines has demonstrated a consistent deletion of a portion of the short arm of chromosome 3(p14-23). DNA prepared from tumors and normal tissues obtained from 24 small cell lung cancer and two extrapulmonary small cell cancer patients was hybridized to four probes that detect restriction fragment length polymorphisms within chromosome region 3p14-21. Of the 25 patients who were heterozygous for at least one marker in this region in the DNA from normal tissue, 23 (92%) showed an unequivocal loss of heterozygosity in the DNA from their tumor tissue. From these studies we conclude that loss of alleles from the short arm of chromosome 3 is a consistent finding in unselected small cell lung cancer patients' tumor DNA.


Asunto(s)
Alelos , Carcinoma de Células Pequeñas/genética , Cromosomas Humanos Par 3 , Neoplasias Pulmonares/genética , Polimorfismo Genético , Polimorfismo de Longitud del Fragmento de Restricción , Adulto , Anciano , Mapeo Cromosómico , ADN de Neoplasias/aislamiento & purificación , Femenino , Heterocigoto , Homocigoto , Humanos , Cariotipificación , Masculino , Persona de Mediana Edad , Hibridación de Ácido Nucleico
16.
J Clin Invest ; 82(2): 686-90, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3403722

RESUMEN

We used a recombinant cDNA probe for human chromogranin A to measure the expression of mRNA encoded by this gene in a variety of normal human tissues and tumor specimens using Northern blot and in situ hybridization analysis. With few exceptions, the expression of chromogranin A mRNA appears to be restricted to normal tissues and tumors of neuroendocrine lineage. However, we have detected mRNA expression of this gene in 1 of 14 cell lines and 2 of 13 tumor specimens of colon adenocarcinoma. The finding of chromogranin A expression in some colon carcinomas suggests that a previously unrecognized subgroup of these tumors has neuroendocrine features. The detection of this subgroup demonstrates the potential for improving tumor classification through the use of techniques and reagents developed by recombinant DNA technology.


Asunto(s)
Cromograninas/aislamiento & purificación , Regulación de la Expresión Génica , Proteínas del Tejido Nervioso/aislamiento & purificación , Células Tumorales Cultivadas/metabolismo , Glándulas Suprarrenales/análisis , Carcinoma/genética , Línea Celular , Cromogranina A , Cromograninas/genética , Neoplasias del Colon/genética , Humanos , Inmunoensayo , Sistemas Neurosecretores/análisis , Hibridación de Ácido Nucleico , ARN Mensajero/aislamiento & purificación , Distribución Tisular
17.
J Clin Invest ; 79(6): 1629-34, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3034978

RESUMEN

44 small cell lung cancer cell lines established from 227 patients were studied for myc family DNA amplification (c-myc, N-myc, and L-myc). Two of 19 lines (11%) established from untreated patients' tumors had DNA amplification (one N-myc and one L-myc), compared with 11 of 25 (5 c-myc, 3 N-myc, and 3 L-myc) cell lines (44%) established from relapsed patients' tumors (P = 0.04). The 19 patients who had tumor cell lines established before chemotherapy treatment survived a median of 14 wk compared with 48 wk for the 123 extensive stage patients who did not have cell lines established (P less than 0.001). Relapsed patients whose cell lines had c-myc DNA amplification survived a shorter period (median of 33 wk) than patients whose cell lines did not have c-myc amplification (median of 53 wk; P = 0.04). We conclude that myc family DNA amplification is more common in tumor cell lines established from treated than untreated patients' tumors, and c-myc amplification in treated patients' tumor cell lines is associated with shortened survival.


Asunto(s)
Carcinoma de Células Pequeñas/genética , Amplificación de Genes , Neoplasias Pulmonares/genética , Familia de Multigenes , Oncogenes , Proteínas de los Retroviridae/genética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Pequeñas/patología , Carcinoma de Células Pequeñas/terapia , Línea Celular , Terapia Combinada , ADN de Neoplasias/análisis , Amplificación de Genes/efectos de los fármacos , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/terapia , Proteína Oncogénica p55(v-myc) , Pronóstico
18.
J Clin Invest ; 100(8): 2133-7, 1997 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-9329980

RESUMEN

Individuals with one aerodigestive tract malignancy have a high incidence of second primary aerodigestive tumors. The mechanism for this field effect has not been determined. We studied an individual with widespread dysplastic changes in the respiratory epithelium but no overt carcinoma. The entire tracheobronchial tree obtained at autopsy was embedded in paraffin, and bronchial epithelial cells were isolated by microdissection. DNA extracted from the microdissected cells was analyzed for point mutations in the p53 tumor suppressor gene. A single, identical point mutation consisting of a G:C to T:A transversion in codon 245 was identified in bronchial epithelium from 7 of 10 sites in both lungs. Epithelium at sites containing the p53 mutation was morphologically abnormal, exhibiting squamous metaplasia and mild to moderate atypia. No invasive tumor was found in the tracheobronchial tree or any other location. Cells from peripheral blood, kidney, liver, and lymph node exhibited no abnormality in the p53 gene. The widespread presence of a single somatic p53 point mutation in the bronchi of a smoker suggests that a single progenitor bronchial epithelial clone may expand to populate broad areas of the bronchial mucosa-a novel mechanism for field carcinogenesis in the respiratory epithelium that may be of importance in assessing individuals for risk of a second primary tumor as well as in devising effective strategies for chemoprevention of lung cancer.


Asunto(s)
Bronquios/patología , Genes p53 , Enfermedades Pulmonares Obstructivas/genética , Mutación Puntual , Fumar/efectos adversos , Anciano , Codón , Epitelio/patología , Exones , Femenino , Humanos , Neoplasias Pulmonares/etiología , Masculino , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo Conformacional Retorcido-Simple
19.
J Clin Invest ; 82(1): 354-9, 1988 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2839551

RESUMEN

The effect of insulin-like growth factor I (IGF-I) on growth of small cell lung cancer (SCLC) cell lines was studied. Western blot analysis of whole cell lysates of cell lines NCI-H345 and NCI-N417 demonstrated the presence of a 16-kD band consistent with an IGF-I precursor molecule. Scatchard plot analysis of cell line NCI-H345 using 125I-labeled IGF-I demonstrated two high affinity specific binding sites (Kd 1.3 and 4.0 nM with maximal rate (Bmax) 200 and 500 fmol/mg protein, respectively). The exogenous addition of IGF-I, IGF-II, or insulin resulted in marked proliferation of human SCLC cells as evaluated using an in vitro growth assay. These peptides stimulated the growth of SCLC cell lines NCI-H82, NCI-H209, NCI-H345, and NCI-N417. The concentration of IGF-I producing maximal SCLC cell growth was 10-100-fold less than that of insulin or IGF-II, whereas the maximal growth stimulated by the optimal concentration of these peptides were similar. An MAb that specifically binds to the IGF-I receptor (but not to the insulin receptor) mediates a dose-dependent inhibition of cell growth in basal media as well as IGF-I, IGF-II, or insulin-supplemented media. The IGF-I receptor thus appears to be the common pathway for the mitogenic activity by IGF-I, IGF-II, and insulin for human SCLC cell lines. The demonstration of an IGF-I precursor molecule, specific IGF-I receptor binding, IGF-I-mediated growth stimulation, and inhibition of basal cell growth by an MAb to the IGF-I receptor suggests that an IGF-I-like molecule can function in vitro as an autocrine growth factor for human SCLC cell lines.


Asunto(s)
Carcinoma de Células Pequeñas/patología , División Celular/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/farmacología , Neoplasias Pulmonares/patología , Somatomedinas/farmacología , Animales , Anticuerpos Monoclonales/fisiología , Carcinoma de Células Pequeñas/metabolismo , Línea Celular , Inhibidores de Crecimiento/fisiología , Humanos , Insulina/farmacología , Factor I del Crecimiento Similar a la Insulina/aislamiento & purificación , Factor II del Crecimiento Similar a la Insulina/farmacología , Neoplasias Pulmonares/metabolismo , Ratones , Precursores de Proteínas/aislamiento & purificación , Receptor de Insulina/análisis , Receptor de Insulina/inmunología , Receptores de Somatomedina , Células Tumorales Cultivadas
20.
Mol Cell Biol ; 8(1): 124-9, 1988 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3275865

RESUMEN

A complex translocation has interrupted the third exon of the c-myc gene in human plasma cell myeloma tumor cells and a derivative cell line (NCI-H929). As a result of this rearrangement, a chimeric mRNA is expressed which commences 5' of the c-myc coding region and includes sequences introduced by the translocation event. All of the detectable c-myc-containing mRNA in the tumor and cell line was derived from this rearranged c-myc allele. This chimeric c-myc mRNA, in which most of the germ line c-myc 3' untranslated region has been replaced, was greater than sevenfold more stable than c-myc transcripts with intact 3' ends. This suggests that the 3' untranslated region may play an important role in c-myc mRNA stability.


Asunto(s)
ADN de Neoplasias/genética , Plasmacitoma/genética , Proteínas Proto-Oncogénicas/genética , Translocación Genética , Secuencia de Bases , Línea Celular , Regulación de la Expresión Génica , Humanos , Datos de Secuencia Molecular , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética
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