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1.
Ann Oncol ; 26(12): 2477-82, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26420428

RESUMEN

BACKGROUND: The clinical implementation of genomic profiling for lung cancer with high-throughput, multiplex tests is warranted to allow prioritization of appropriate therapies for individual patients. We have now applied such testing to detect actionable mutations that may inform treatment recommendations in lung cancer. PATIENTS AND METHODS: We prospectively applied amplicon sequencing panels that cover both mutational hotspots in 22 genes related to lung and colon tumorigenesis as well as 72 major variants of ALK, RET, ROS1, and NTRK1 fusion transcripts. We then determined the proportion of patients who received genotype-directed therapy and their overall survival (OS). RESULTS: Tumor specimens from 110 patients with lung cancer recruited between July 2013 and March 2015 were analyzed. The most common genetic alterations were TP53 mutations in 42 patients, followed by EGFR mutations in 25, STK11 mutations in 12, and KRAS mutations in 10. Potentially actionable mutations were identified in 44 patients including 50% of those with adenocarcinoma and 14% of those with squamous cell carcinoma. The OS of patients with advanced or recurrent cancer who had an actionable mutation and received targeted therapy (median OS not achieved) was significantly longer than that of those with no mutation (18.1 months, P = 0.041) or of those with a mutation not so treated (6.1 months, P = 0.0027). CONCLUSIONS: Multiplex genomic testing was performed on formalin-fixed, paraffin-embedded tumor specimens with a success rate of ≥95%. Such testing can assist physicians in matching patients with approved or experimental targeted treatments. CLINICAL TRIAL REGISTRATION: The University Medical Hospital Information Network (UMIN) Clinical Trials Registry under the identifier UMIN000014782.


Asunto(s)
Toma de Decisiones Clínicas/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Análisis de Secuencia de ARN/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sistema de Registros
2.
Transfus Med ; 20(2): 95-103, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19883399

RESUMEN

To evaluate the specific reactivity of HLA Class I antibodies (HLA-I Abs) in acute non-hemolytic transfusion reactions (ANHTRs) using solid phase assays (SPAs) and conventional complement-dependent lymphocyte cytotoxicity test (LCT). ANHTRs are major issues in transfusion medicine. Anti-leukocyte antibodies have been implicated as one of the causative agents of transfusion-related acute lung injury (TRALI) and febrile reaction. Antibodies to HLA Class I and/or Class II (HLA Abs) have been intensively studied using SPAs for TRALI, but not for febrile reaction. About 107 patients and 186 donors associated with ANHTRs were screened for HLA Abs by SPAs such as enzyme-linked immunosorbent assay (ELISA) and the Luminex method. When HLA-I Ab was detected, its specific reactivity was evaluated by comparing its specificity identified by the Luminex method using recombinant HLA molecules and cognate HLA antigens (Ags), as well as LCT with or without anti-human globulin (AHG). The incidences of HLA Abs were as high as 32.7% of patients' serum samples and 16% of donors' serum samples. The incidence of HLA-I Abs did not differ significantly between cases of febrile and allergic reactions. However, HLA-I Abs associated with febrile reaction showed a significantly higher rate of possessing specific reactivity to cognate HLA Ags than those associated with allergic reactions. In addition, the Luminex method enabled the detection of HLA-I Abs much earlier than AHG-LCT in serum samples from a patient with febrile reaction and platelet transfusion refractoriness (PTR). SPAs seem more useful than AHG-LCT for evaluating reactivity of antibodies in ANHTR cases.


Asunto(s)
Lesión Pulmonar Aguda/etiología , Anafilaxia/etiología , Fiebre/etiología , Antígenos HLA/inmunología , Prueba de Histocompatibilidad/métodos , Isoanticuerpos/sangre , Reacción a la Transfusión , Urticaria/etiología , Enfermedad Aguda , Lesión Pulmonar Aguda/inmunología , Adulto , Anciano , Anafilaxia/inmunología , Especificidad de Anticuerpos , Reacciones Antígeno-Anticuerpo , Niño , Pruebas Inmunológicas de Citotoxicidad , Ensayo de Inmunoadsorción Enzimática , Femenino , Fiebre/inmunología , Fluorometría , Estudios de Seguimiento , Humanos , Japón , Masculino , Persona de Mediana Edad , Neoplasias/inmunología , Neoplasias/terapia , Urticaria/inmunología
3.
J Cell Biol ; 148(1): 101-14, 2000 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-10629221

RESUMEN

Kettin is a giant muscle protein originally identified in insect flight muscle Z-discs. Here, we determined the entire nucleotide sequence of Drosophila melanogaster kettin, deduced the amino acid sequence of its protein product (540 kD) along with that of the Caenorhabditis elegans counterpart, and found that the overall primary structure of Kettin has been highly conserved in evolution. The main body of Drosophila Kettin consists of 35 immunoglobulin C2 domains separated by spacers. The central two thirds of spacers are constant in length and share in common two conserved motifs, putative actin binding sites. Neither fibronectin type III nor kinase domains were found. Kettin is present at the Z-disc in several muscle types. Genetic analysis showed that kettin is essential for the formation and maintenance of normal sarcomere structure of muscles and muscle tendons. Accordingly, embryos lacking kettin activity cannot hatch nor can adult flies heterozygous for the kettin mutation fly.


Asunto(s)
Proteínas de Drosophila , Drosophila melanogaster/fisiología , Evolución Molecular , Vuelo Animal/fisiología , Proteínas de Insectos/fisiología , Proteínas Musculares/fisiología , Músculos/fisiología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Caenorhabditis elegans , Conectina , ADN Complementario , Drosophila melanogaster/embriología , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Genes de Insecto , Proteínas de Insectos/biosíntesis , Proteínas de Insectos/genética , Operón Lac , Larva , Datos de Secuencia Molecular , Proteínas Musculares/biosíntesis , Proteínas Musculares/genética , Músculos/embriología , Músculos/metabolismo , Mutación , Proteínas Quinasas/genética , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Secuencias Repetitivas de Aminoácido , Sarcómeros/ultraestructura , Homología de Secuencia de Aminoácido
4.
Science ; 275(5299): 543-7, 1997 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-8999801

RESUMEN

The morphology of axon terminals changes with differentiation into mature synapses. A molecule that might regulate this process was identified by a screen of Drosophila mutants for abnormal motor activities. The still life (sif) gene encodes a protein homologous to guanine nucleotide exchange factors, which convert Rho-like guanosine triphosphatases (GTPases) from a guanosine diphosphate-bound inactive state to a guanosine triphosphate-bound active state. The SIF proteins are found adjacent to the plasma membrane of synaptic terminals. Expression of a truncated SIF protein resulted in defects in neuronal morphology and induced membrane ruffling with altered actin localization in human KB cells. Thus, SIF proteins may regulate synaptic differentiation through the organization of the actin cytoskeleton by activating Rho-like GTPases.


Asunto(s)
Proteínas de Drosophila , Drosophila/metabolismo , Factores de Intercambio de Guanina Nucleótido , Terminales Presinápticos/metabolismo , Proteínas de Unión al GTP rac , Actinas/metabolismo , Secuencia de Aminoácidos , Animales , Axones/fisiología , Membrana Celular/ultraestructura , Citoesqueleto/fisiología , Citoesqueleto/ultraestructura , ADN Complementario/genética , Drosophila/embriología , Drosophila/genética , Embrión no Mamífero/metabolismo , GTP Fosfohidrolasas/metabolismo , Proteínas de Unión al GTP/genética , Proteínas de Unión al GTP/metabolismo , Expresión Génica , Genes de Insecto , Humanos , Hibridación in Situ , Células KB , Datos de Secuencia Molecular , Movimiento , Mutación , Unión Neuromuscular/metabolismo , Transducción de Señal
5.
Food Chem Toxicol ; 46(6): 2190-200, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18381228

RESUMEN

The beneficial effects of tea catechins are well documented. We evaluated the genotoxic potential of a green tea catechin preparation using established genotoxicity assays, including a bacterial reverse mutation assay (Ames test), a chromosomal aberration assay in cultured Chinese hamster lung cells (CHL/IU), a mouse lymphoma L5178Y/tk assay, and a bone marrow micronucleus (MN) assay in ICR CD mice and SD rats. No significant increases in the number of revertant colonies were observed in the Ames test, but positive responses were observed in two in vitro assays: the chromosomal aberration assay and mouse lymphoma L5178/tk assay. However, the in vivo study demonstrated no significant increase in micronucleated polychromatic erythrocytes (MNPCE) in the bone marrow of both ICR CD mice and SD rats administered a high dose of the green tea catechin preparation up to 2000mg/kg. Combined with favorable epidemiological information suggesting a chemopreventive effect of tea catechins on carcinogenesis, we conclude that green tea catechin presents no significant genotoxic concern under the anticipated conditions of use. These results are consistent with other genotoxicity studies of tea catechins, which show minimal, if any, genotoxic potential.


Asunto(s)
Catequina/toxicidad , Mutágenos , Té/química , Animales , Células de la Médula Ósea/efectos de los fármacos , Línea Celular , Línea Celular Tumoral , Aberraciones Cromosómicas/efectos de los fármacos , Cricetinae , Relación Dosis-Respuesta a Droga , Ratones , Ratones Endogámicos ICR , Pruebas de Micronúcleos , Pruebas de Mutagenicidad , Ratas , Ratas Sprague-Dawley , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Fracciones Subcelulares/efectos de los fármacos , Fracciones Subcelulares/metabolismo , Timidina Quinasa/genética
6.
Transplant Proc ; 40(7): 2289-91, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18790214

RESUMEN

ABO-incompatible kidney transplantation has become a popular alternative to kidney transplantation in Japan because of the severe shortage of cadaveric donors. In our institution, 21 cases of ABO-incompatible kidney transplantation were performed from April 2004, to October 2007. Recipient age was 42.8 +/- 14.5 years old; there were 9 men and 12 women. Duration of hemodialysis was 1,914 +/- 2,343 days. Donor operation was performed using a complete laparoscopic procedure. Recipient's splenectomy was performed using a hand-assisted laparoscopic procedure and kidney transplantation was performed with a standard method using an extraperitoneal approach. Pretransplant immunosuppressive protocol includes an administration of mycophenolate mofetil, tacrolimus, predonisolone, splenectomy, double filtration plasmapheresis (DFPP), and plasma exchange (PE). All patients showed an immediate graft function and their serum creatinine levels promptly decreased to 1.48 +/- 0.99 mg/dL on day 7 and 1.21 +/- 0.72 mg/dL on day 30. Both immunoglobulin (Ig)M and IgG titers were maintained at much lower levels for 7 days after transplantation in all patients. Cytomegalovirus antigenemia was observed in 11 patients (52.4%). One patient (4.8%) developed a Pneumocystis Carinii pneumonia and the formation of lymphocele was observed in one patient (4.8%). Total patient survival at 3 years was 95.2%, and graft survival at 3 years was 90.5%, which were almost equal to those in the patients who underwent ABO-matched, compatible kidney transplantation.


Asunto(s)
Sistema del Grupo Sanguíneo ABO/inmunología , Incompatibilidad de Grupos Sanguíneos , Supervivencia de Injerto/inmunología , Fallo Renal Crónico/cirugía , Trasplante de Riñón/inmunología , Cadáver , Humanos , Isoanticuerpos/sangre , Trasplante de Riñón/mortalidad , Donadores Vivos , Estudios Retrospectivos , Análisis de Supervivencia , Donantes de Tejidos , Resultado del Tratamiento
7.
Transplant Proc ; 40(7): 2416-8, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18790253

RESUMEN

Reversible posterior leukoencephalopathy syndrome (RPLS) is one of the important side effects of calcineurin inhibitors (CNIs). Magnetic resonance imaging (MRI) of the brain is useful for the diagnosis of RPLS, showing the edema primarily in the cortex and subcortical white matter of the posterior brain regions. Interruption of CNIs is essential for the treatment of patients with RPLS. Herein we have described 2 cases (1.7%) of RPLS induced by CNIs after kidney transplantation. The first case was a 56-year-old man with chronic renal failure due to diabetic nephropathy who received a living-related kidney transplantation in 2006. Initial immunosuppressive therapy consisted of cyclosporine, mycophenolate mofetil (MMF), prednisolone, and basiliximab. Four months after transplantation, he developed unconsciousness and paralysis. The second case was a 24-year-old woman with end-stage renal disease due to Alport syndrome who received an ABO-incompatible living-related kidney transplantation. Initial immunosuppressive therapy consisted of tacrolimus, MMF, prednisolone, and basiliximab. On postoperative day 3, she developed convulsions and unconsciousness. In both patients, RPLS was diagnosed with neurological symptoms and MRI findings at early stage of the disease, and they recovered rapidly from the disease by the interruption of CNIs. Our data demonstrated that early diagnosis and immediate interruption of CNIs were essential for the treatment of RPLS after kidney transplantation.


Asunto(s)
Inhibidores de la Calcineurina , Inmunosupresores/efectos adversos , Trasplante de Riñón/inmunología , Ácido Micofenólico/análogos & derivados , Síndrome de Leucoencefalopatía Posterior/inducido químicamente , Adulto , Encéfalo/patología , Femenino , Humanos , Fallo Renal Crónico/cirugía , Donadores Vivos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Ácido Micofenólico/efectos adversos , Nefritis Hereditaria/cirugía , Síndrome de Leucoencefalopatía Posterior/patología
8.
Transplant Proc ; 40(8): 2565-7, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18929802

RESUMEN

We performed the first case of simultaneous pancreas and kidney transplantation from a living donor (LDSPK) in 2004. We examined the quality of life (QOL) of performed 6 recipients and 5 donors among 8 LDSPK from 2004 to 2007 at our institution using Short Form 36. All recipients achieved insulin and hemodialysis independence after LDSPK with positive serum C-peptide levels. Before LDSPK, all scores of the 8 specific domains of the recipients were low (28.2 +/- 10.6), indicating extremely poor QOL. Both the Physical and the Mental Component Summary Scores (PCS/MCS) quickly increased after LDSPK. PCS at 6, 12, and 24 months after LDSPK were significantly higher than the pretransplantation level. MCS were also significantly higher than the pretransplantation level. LDSPK showed prominent QOL improvement for the recipient. Complications were not observed in any donor. Although PCS decreased at 6 months after the operation, it recovered at 12 and at 24 months after the operation. MCS was maintained at more than 50 from 6 to 24 months after the operation. QOL was well preserved in the LDSPK donors despite the major surgery. In conclusion, LDSPK was confirmed to be a potent tool for treatment of type 1 diabetes mellitus patients with end-stage renal disease (ESRD) by complete normalization of glucose metabolism and renal function. In addition to these medical advantages, both their physical and mental QOL were improved by LDSPK.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Nefropatías Diabéticas/cirugía , Fallo Renal Crónico/cirugía , Trasplante de Riñón/fisiología , Trasplante de Páncreas/fisiología , Calidad de Vida , Adulto , Padre , Femenino , Humanos , Insulina/uso terapéutico , Trasplante de Riñón/psicología , Donadores Vivos , Masculino , Persona de Mediana Edad , Madres , Nefrectomía/métodos , Trasplante de Páncreas/psicología , Pancreatectomía/métodos , Diálisis Renal , Encuestas y Cuestionarios
9.
Transplant Proc ; 40(8): 2562-4, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18929801

RESUMEN

For the safe operation of living donor pancreas transplantation, we investigated the utility of 11C-methionine positron emission tomography (PET) to examine the function of the residual pancreatic head in patients with pancreatic disease undergoing distal pancreatectomy and in living donors of pancreas transplantation. After 6 hours of fasting, we intravenously injected 370 to 740 MBq 11C-methionine. PET was scanned 30 minutes after injection. 11C-methionine PET uptake by the pancreatic head versus body/tail was expressed as a standardized uptake value (SUV). The SUVs of the pancreatic head were compared before versus after surgery. The SUVs of the pancreatic head in patients before and after distal pancreatectomy were 15.3 +/- 6.0 and 18.2 +/- 2.4, respectively. The SUVs of the pancreatic head in donors before and after distal pancreatectomy were 16.1 +/- 1.0 and 14.7 +/- 1.4, respectively. Both patients and donors showed no significant difference in SUVs of the pancreatic head before and after surgery. However, the SUVs of the residual pancreatic head were elevated after distal pancreatectomy in 80% of patients and 50% of donors. These data indicated that the function of the pancreatic head may be maintained or improved after distal pancreatectomy. 11C-methionine PET may become a potent modality to evaluate segmental pancreatic function for a safe living donor operation.


Asunto(s)
Donadores Vivos , Trasplante de Páncreas/métodos , Páncreas/anatomía & histología , Pancreatectomía/métodos , Transporte Biológico , Radioisótopos de Carbono , Humanos , Metionina/metabolismo , Páncreas/diagnóstico por imagen , Páncreas/metabolismo , Tomografía de Emisión de Positrones/métodos , Radiografía
10.
Transplant Proc ; 40(8): 2568-70, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18929803

RESUMEN

We performed 6 islet transplantations in 4 type 1 diabetes mellitus patients. From September 2003 to April 2007, 23 islet isolations were performed from pancreata of non-heart-beating donors. The pancreata preserved using a 2-layer method or simple cold storage in University of Wisconsin solution were transferred to our cell processing center. The islet isolation was performed according to the Edmonton protocol with some modifications. The immunosuppressive protocol was achieved using sirolimus, tacrolimus, and anti-CD25 antibody (basiliximab). Islet yield was 400 to 491,040 IEQ and purity was 1% to 70%. Stimulation indices upon static incubation were 1.38 to 11.69. All patients who underwent islet transplantation showed positive serum C-peptide levels immediately after transplantation. Although insulin independence was not achieved, they displayed stabilized blood glucose levels, reduced insulin doses, and disappearance of hypoglycemic unawareness. Although stomatitis and diarrhea due to the side effects of sirolimus were observed in 2 patients, there were no severe complications. In patient 1, serum C-peptide levels decreased gradually from 1 year after transplantation. In conclusion, successful islet transplantation was possible using islets isolated from the pancreata of non-heart-beating donors. Further improvements are needed to achieve prolonged graft survival.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Trasplante de Islotes Pancreáticos/métodos , Glucemia/metabolismo , Cadáver , Separación Celular , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/inmunología , Quimioterapia Combinada , Humanos , Inmunosupresores/uso terapéutico , Islotes Pancreáticos/citología , Reoperación/estadística & datos numéricos , Estudios Retrospectivos , Donantes de Tejidos
11.
Oncogene ; 25(17): 2537-45, 2006 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-16331254

RESUMEN

MicroRNAs (miRNAs) are a non-coding family of genes involved in post-transcriptional gene regulation. These transcripts are associated with cell proliferation, cell differentiation, cell death and carcinogenesis. We analysed the miRNA expression profiles in 25 pairs of hepatocellular carcinoma (HCC) and adjacent non-tumorous tissue (NT) and nine additional chronic hepatitis (CH) specimens using a human miRNA microarray. Targets and references samples were co-hybridized to a microarray containing whole human mature and precursor miRNA sequences. Whereas three miRNAs exhibited higher expression in the HCC samples than that in the NT samples, five miRNAs demonstrated lower expression in the HCC samples than in the NT samples (P<0.0001). Classification of samples as HCC or NT by using support vector machine algorithms based on these data provided an overall prediction accuracy of 97.8% (45/46). In addition, the expression levels of four miRNAs were inversely correlated with the degree of HCC differentiation (P<0.01). A comparison of CH and liver cirrhosis samples revealed significantly different pattern of miRNA expression (P<0.01). There were no differences, however, between hepatitis B-positive and hepatitis C-positive samples. This information may help clarify the molecular mechanisms involved in the progression of liver disease, potentially serving as a diagnostic tool of HCC.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Hepatitis C Crónica/metabolismo , Neoplasias Hepáticas/metabolismo , Hígado/metabolismo , MicroARNs/fisiología , Análisis de Secuencia por Matrices de Oligonucleótidos , Adulto , Anciano , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Hepatitis C Crónica/genética , Hepatitis C Crónica/patología , Humanos , Hígado/patología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , ARN Mensajero/genética , ARN Mensajero/metabolismo
12.
Transplant Proc ; 48(1): 229-33, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26915873

RESUMEN

OBJECTIVE: The use of positron-emission tomography (PET) with (18)F-fluorodeoxyglucose (FDG) -labeled islets has been considered to be a potential modality to visualize and quantify early engraftment of islet transplantation. The objective of this study was to evaluate the early islets' survival of the FDG-labeled islets with or without warm ischemic stress in portal transplanted rats using PET and autoradiography. METHODS: Islets were isolated from Lewis rat pancreata with or without 30-minute warm ischemia times (WITs). For islets' labeling, 300 islets were incubated with 3 MBq FDG for 60 minutes. FDG-labeled islets were transplanted into the liver via portal vein. In in vivo study, a PET study was scanned for 90 minutes and the FDG uptake was expressed as percentage of liver injection dose (ID). In ex vivo study, the liver was exposed for 30 minutes with single fluorescence autoradiography. RESULTS: In the PET study, the percentage of liver ID of the islets without WIT was 27.8 and that of the WIT islets was 20.1 at the end of islet transplantation. At 90 minutes after transplantation, the percentage of liver ID was decreased to 14.7 in the islets without WIT and 10.1 in the WIT islets. In the autoradiogram, the number of hot spots was more obviously visualized in the liver transplanted without WIT islets than in the liver transplanted with WIT islets. CONCLUSION: Almost 50% of the islets were immediately lost in both the islets without WIT and those with WIT transplantation in the early period. However, islet survival was 1.4 times higher in the islets without WIT than that in those with WIT in the early engraftment phase.


Asunto(s)
Autorradiografía/métodos , Trasplante de Islotes Pancreáticos/métodos , Islotes Pancreáticos/diagnóstico por imagen , Vena Porta/trasplante , Tomografía de Emisión de Positrones/métodos , Animales , Supervivencia Celular , Fluorodesoxiglucosa F18 , Islotes Pancreáticos/fisiopatología , Hígado , Masculino , Radiofármacos , Ratas , Ratas Endogámicas Lew , Coloración y Etiquetado , Trasplantes , Isquemia Tibia/efectos adversos
13.
Oncogene ; 7(2): 323-9, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1549353

RESUMEN

smg p21A and -B (smg p21s) are ras p21-like small GTP-binding proteins (G proteins) with the same putative effector domain as ras p21s. Both smg p21A mRNA and smg p21B mRNA were detected in CMK, a human megakaryocytic leukemia cell line, and their levels were markedly elevated by treatment with 12-O-tetradecanoyl-phorbol-13-acetate (TPA), which caused the differentiation of this cell line into more mature megakaryocytes. The smg p21 protein molecules also increased during the TPA-induced differentiation of CMK cells. The mRNA level of glycoprotein IIb (GPIIb), a typical marker of the megakaryocytes, was increased by this treatment, but the time course of the increase in the smg p21 mRNA levels as more rapid than that of the increase in the GPIIb mRNA level. Ha-ras p21 mRNA was undetectable, but both Ki- and N-ras p21 mRNAs were detected in CMK cells and their levels were also increased during TPA-induced differentiation of CMK cells, although to a lesser extent than those of smg p21 mRNAs. Protein kinase C inhibitors inhibited the basal and TPA-induced smg p21A mRNA level, but cyclic AMP-elevating prostaglandin E1 or Ca(2+)-mobilizing ionomycin did not inhibit them. Cycloheximide enhanced the basal and TPA-induced smg p21A mRNA levels. Actinomycin D blocked the TPA-induced smg p21A mRNA levels, but showed no detectable effect on the elevated smg p21A mRNA level which was induced by pretreatment with TPA. A dramatic increase in the smg p21 mRNA levels was also observed in other leukemia cell lines during TPA-induced differentiation. These results suggest that TPA stimulated expression of the smg p21A gene, presumably through the action of protein kinase C at the transcriptional level rather than at the post-transcriptional level, in hematopoietic leukemia cells.


Asunto(s)
Proteínas de Unión al GTP/genética , Regulación Neoplásica de la Expresión Génica , Trombocitemia Esencial/genética , Alprostadil/metabolismo , Calcio/fisiología , Diferenciación Celular/efectos de los fármacos , Expresión Génica , Genes ras , Humanos , Técnicas In Vitro , Inhibidores de Proteínas Quinasas , ARN Mensajero/genética , ARN Neoplásico/genética , Acetato de Tetradecanoilforbol/farmacología , Células Tumorales Cultivadas , Proteínas de Unión al GTP rap
14.
Oncogene ; 20(43): 6233-40, 2001 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-11593432

RESUMEN

Proviral tagging has been used in animals as a powerful tool for cancer genetics. We show that a similar approach is possible in patients with hepatocellular carcinoma (HCC) infected by Hepatitis B Virus (HBV), a human pararetrovirus which may act by insertional mutagenesis. In this work, the HBV genome is used as a probe to identify cancer-related genes. By using HBV-Alu-PCR, we obtained 21 HBV/cellular DNA junctions from 18 different patients. In six of 21, we found the HBV DNA integrated into a cellular gene: (1) Sarco/Endoplasmic Reticulum Calcium ATPase1 Gene; (2) Thyroid Hormone Receptor Associated Protein 150 alpha Gene; (3) Human Telomerase Reverse Transcriptase Gene; (4) Minichromosome Maintenance Protein (MCM)-Related Gene; (5) FR7, a new gene expressed in human liver and cancer tissues; and (6) Nuclear Matrix Protein p84 Gene. Seven junctions contained unique cellular sequences. In the remaining eight, the HBV DNA was next to repetitive sequences, five of them of LINE1 type. The cellular genes targeted by HBV are key regulators of cell proliferation and viability. Our results show that studies on HBV-related HCCs allow to identify cellular genes involved in cancer. We therefore propose this approach as a valuable tool for functional cancer genomic studies in humans.


Asunto(s)
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virología , ADN/metabolismo , Virus de la Hepatitis B/genética , Reacción en Cadena de la Polimerasa/métodos , Secuencia de Bases , Northern Blotting , División Celular , ADN Complementario/metabolismo , Exones , Humanos , Intrones , Modelos Genéticos , Datos de Secuencia Molecular , Mutación , Secuencias Repetitivas de Ácidos Nucleicos
15.
Oncogene ; 19(25): 2877-86, 2000 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-10871838

RESUMEN

We have used the Hepatitis B Virus DNA genome as a probe to identify genes clonally mutated in vivo, in human liver cancers. In a tumor, HBV-DNA was found to be integrated into the gene encoding Sarco/Endoplasmic Reticulum Calcium ATPase (SERCA), which pumps calcium, an important intracellular messenger for cell viability and growth, from the cytosol to the endoplasmic reticulum. The HBV X gene promoter cis-activates chimeric HBV X/SERCA1 transcripts, with splicing of SERCA1 exon 11, encoding C-terminally truncated SERCA1 proteins. Two chimeric HBV X/SERCA1 proteins accumulate in the tumor and form dimers. In vitro analyses have demonstrated that these proteins localize to the ER, determine its calcium depletion and induce cell death. We have also shown that these biological effects are related to expression of the SERCA, rather than of the viral moiety. This report involves for the first time the expression of mutated SERCA proteins in vivo in a tumor cell proliferation and in vitro in the control of cell viability. Oncogene (2000).


Asunto(s)
Apoptosis/genética , ATPasas Transportadoras de Calcio/genética , Virus de la Hepatitis B/fisiología , Mutagénesis Insercional/genética , Anciano , ATPasas Transportadoras de Calcio/metabolismo , Dimerización , Humanos , ARN Mensajero/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Retículo Sarcoplasmático/enzimología , Células Tumorales Cultivadas , Integración Viral
16.
Biochim Biophys Acta ; 1163(2): 223-6, 1993 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-7683914

RESUMEN

All reverse transcriptases (RTs) so far examined are known to possess in common a stretch of 7 amino acids called the YXDD box. Various mutations were introduced in vitro into the nucleotide sequence coding for this box of Moloney murine leukaemia virus (Mo-MuLV) RT. The YXDD box of Mo-MuLV could be replaced by the counterpart of a Drosophila retrotransposon, 17.6, without loss of activity, while virtually complete loss of activity was detected in the case of replacement of the YXDD box of Rous sarcoma virus RT. Amino-acid substitution at position X resulted in significant change in divalent metal ion preference and enzyme activity, thus indicating that the YXDD box possibly constitutes a part of the active center of RT through metal ion binding.


Asunto(s)
Drosophila/genética , Virus de la Leucemia Murina de Moloney/genética , ADN Polimerasa Dirigida por ARN/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Quimera , Genes Virales , Datos de Secuencia Molecular , Mutagénesis , Mutación
17.
Biochim Biophys Acta ; 740(4): 390-401, 1983 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-6309235

RESUMEN

In a previous communication (Saigo, K., Millstein, L. and Thomas, C.A., Jr. (1981) Cold Spring Harbor Symp. Quant. Biol. 45, 815-827), the overall structure of histone genes of Schneider line 2 cells was shown to extensively differ from that of Oregon-R embryo from which the cell line was established, and it was speculated that the histone genes might be reshuffled extensively during either the periods of the establishment, or maintenance of cell lines, or both. To establish the validity of this notion the structure of histone genes was examined in Drosophila melanogaster cultured cells. The overall organization of histone gene clusters was found to be stably maintained in both the periods for the establishment and maintenance of cultured cells, indicating that the previous assumption is inadequate. Instead of an extensive rearrangement, minor structural changes were found to occasionally occur probably by simple base substitutions and/or, deletion or insertion of very short DNA pieces. It was also shown that the extensive variation in structures of histone genes in cultured cells such as Schneider line 2 are attributable to polymorphism on the level of individual flies.


Asunto(s)
Genes , Histonas/genética , Polimorfismo Genético , Animales , Secuencia de Bases , Línea Celular , Clonación Molecular , ADN/genética , Enzimas de Restricción del ADN , Drosophila melanogaster/genética , Estabilidad de Medicamentos , Embrión no Mamífero/metabolismo , Hibridación de Ácido Nucleico
18.
Biochim Biophys Acta ; 607(3): 530-5, 1980 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-6772223

RESUMEN

Various cultured cell lines of Drosophila melanogaster contain 10 to 13 discrete double-stranded RNAs ranging in length from 1 to 4 kilobases. These RNAs were characterized by nuclease susceptibility, density, solubility in LiCl, thermostability, electron microscopy and gel electrophoresis. These RNAs, which are similar to Reo virus RNA could not be detected in adult or embryonic tissues.


Asunto(s)
Drosophila melanogaster/análisis , ARN Bicatenario/análisis , Células Cultivadas , Centrifugación por Gradiente de Densidad , Electroforesis en Gel de Agar , Calor , Humanos , Microscopía Electrónica , ARN Viral/análisis , Ribonucleasas
19.
Biochim Biophys Acta ; 1216(1): 65-72, 1993 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-8218417

RESUMEN

Proteasome, a large protein complex with ATP-dependent protease activities, is composed of non-identical but closely related multi-subunits. Using cDNAs for rat proteasome subunits as probes, we obtained three cDNA clones for two Xenopus proteasome subunits from ovary cDNA library. The primary structures of the three cDNAs showed high homology to the corresponding proteasome subunits of other mammalian species (above 90%) and also considerable homology to those of Drosophila and yeast. These results indicate that the sequences of proteasome subunits are well conserved during evolution. Northern blot hybridization revealed that RNAs for the newly isolated subunits (XC8 and XC9) and the previously isolated subunit (XC3) occur at very high levels in testis and ovary, at moderately high levels in lung, skin kidney and spleen, and at low levels in liver, stomach and muscle. It was also shown that relative amounts of the mRNAs for the three subunits are similar in all the adult tissues examined. From these results, we concluded that the expression of the genes for the three subunits (XC3 XC8 and XC9-1) takes place in a roughly coordinated manner in different adult tissues.


Asunto(s)
Cisteína Endopeptidasas/genética , ADN Complementario/biosíntesis , Complejos Multienzimáticos/genética , Xenopus/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Cisteína Endopeptidasas/metabolismo , Expresión Génica , Datos de Secuencia Molecular , Complejos Multienzimáticos/metabolismo , Complejo de la Endopetidasa Proteasomal , ARN Mensajero/análisis
20.
Biochim Biophys Acta ; 1235(2): 467-9, 1995 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-7756357

RESUMEN

A genomic DNA fragment encoding a G protein-coupled seven-transmembrane receptor was isolated from Medaka fish, Oryzias latipes. The encoded protein is similar in sequence to other receptors including catecholamine, histamine and serotonin receptors. However, the similarity is much lower than those among members of these receptor subfamilies, thus suggesting this seven-transmembrane receptor to be an orphan receptor whose ligand has not yet been identified. Genomic Southern blot analysis suggested that the fish genome contains additional receptor genes related to the isolated gene, indicating that this novel receptor, possibly with its related receptors, might constitute a novel subfamily of the seven-transmembrane receptor superfamily.


Asunto(s)
Membrana Celular/química , Clonación Molecular , Oryzias/genética , Receptores de Catecolaminas/química , Receptores de Superficie Celular/genética , Receptores Histamínicos/química , Receptores de Serotonina/química , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Proteínas de Unión al GTP/metabolismo , Datos de Secuencia Molecular , Receptores de Superficie Celular/química , Homología de Secuencia
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