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2.
Rev Sci Instrum ; 93(3): 034703, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35365006

RESUMEN

In semiconductor device history, a trend is observed where narrowing and increasing the number of material layers improve device functionality, with diodes, transistors, thyristors, and superlattices following this trend. While superlattices promise unique functionality, they are not widely adopted due to a technology barrier, requiring advanced fabrication, such as molecular beam epitaxy and lattice-matched materials. Here, a method to design quantum devices using amorphous materials and physical vapor deposition is presented. It is shown that the multiplication gain M depends on the number of layers of the superlattice, N, as M = kN, with k as a factor indicating the efficiency of multiplication. This M is, however, a trade-off with transit time, which also depends on N. To demonstrate, photodetector devices are fabricated on Si, with the superlattice of Se and As2Se3, and characterized using current-voltage (I-V) and current-time (I-T) measurements. For superlattices with the total layer thicknesses of 200 nm and 2 µm, the results show that k200nm = 0.916 and k2µm = 0.384, respectively. The results confirm that the multiplication factor is related to the number of superlattice layers, showing the effectiveness of the design approach.

3.
Lupus ; 28(7): 826-833, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31068068

RESUMEN

OBJECTIVES: We investigated the effect of hydroxychloroquine (HCQ) on S100A8 and S100A9 serum levels in systemic lupus erythematosus (SLE) patients with low disease activity receiving immunosuppressants. METHODS: SELENA-SLEDAI, Cutaneous Lupus Erythematous Disease Area and Severity Index (CLASI) and serum levels of complement factors, anti-dsDNA antibodies, and white blood cell, lymphocyte, and platelet counts were used to evaluate disease activity, cutaneous disease activity, and immunological activity, respectively. Serum S100A8 and S100A9 were measured at HCQ administration and after 3 or 6 months using ELISA. RESULTS: S100A8 and S100A9 serum levels were elevated at baseline and the magnitude of decrease from baseline at 3 and 6 months after HCQ administration was greater in patients with renal involvement than in those without (baseline: S100A8, p = 0.034; S100A9, p = 0.0084; decrease: S100A8, p = 0.049; S100A9, p = 0.023). S100 modulation was observed in patients with (n = 17; S100A8, p = 0.0011; S100A9, p = 0.0002) and without renal involvement (n = 20; S100A8, p = 0.0056; S100A9, p = 0.0012), and was more apparent in patients with improved CLASI activity scores (improved: S100A8, p = 0.013; S100A9, p = 0.0032; unimproved: S100A8, p = 0.055; S100A9, p = 0.055). No associations were observed for immunological biomarkers. CONCLUSION: HCQ may improve organ involvement in SLE by modulating S100 protein levels, especially in patients with renal or skin involvement.


Asunto(s)
Antirreumáticos/uso terapéutico , Calgranulina A/sangre , Calgranulina B/sangre , Hidroxicloroquina/uso terapéutico , Lupus Eritematoso Cutáneo/tratamiento farmacológico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Adulto , Biomarcadores/sangre , Femenino , Humanos , Lupus Eritematoso Cutáneo/sangre , Lupus Eritematoso Sistémico/sangre , Nefritis Lúpica/sangre , Nefritis Lúpica/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
5.
Leukemia ; 31(1): 203-212, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27349810

RESUMEN

Dasatinib treatment markedly increases the number of large granular lymphocytes (LGLs) in a proportion of Ph+ leukemia patients, which associates with a better prognosis. The lymphocytosis is predominantly observed in cytomegalovirus (CMV)-seropositive patients, yet detectable CMV reactivation exists only in a small fraction of patients. Thus, etiology of the lymphocytosis still remains unclear. Here, we identified NK cells as the dominant LGLs expanding in dasatinib-treated patients, and applied principal component analysis (PCA) to an extensive panel of NK cell markers to explore underlying factors in NK cell activation. PCA displayed phenotypic divergence of NK cells that reflects CMV-associated differentiation and genetic differences, and the divergence was markedly augmented in CMV-seropositive dasatinib-treated patients. Notably, the CMV-associated highly differentiated status of NK cells was already observed at leukemia diagnosis, and was further enhanced after starting dasatinib in virtually all CMV-seropositive patients. Thus, the extensive characterization of NK cells by PCA strongly suggests that CMV is an essential factor in the NK cell activation, which progresses stepwise during leukemia and subsequent dasatinib treatment most likely by subclinical CMV reactivation. This study provides a rationale for the exploitation of CMV-associated NK cell activation for treatment of leukemias.


Asunto(s)
Citomegalovirus , Dasatinib/uso terapéutico , Células Asesinas Naturales/inmunología , Leucemia Mielógena Crónica BCR-ABL Positiva/inmunología , Análisis de Componente Principal , Humanos , Células Asesinas Naturales/microbiología , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Activación Viral
8.
Artículo en Inglés | MEDLINE | ID: mdl-17282211

RESUMEN

We tested the effects of some kinds of time-varying magnetic fields (0-1.2T) on neurotransmitter-induced transient increases in intracellular Ca2+concentration ([Ca2+]) of cultured chromaffin and HeLa cells. After these cells were exposed for 2 hours to these magnetic fields, transient increases in [Ca2+]i by addition of acetylcholine or histamine were measured. In control cells, after addition of these neurotransmitters [Ca2+]i was increased immediately and then decreased with time in both cells. But, addition of these drugs to the magnetic fields exposed cells increased [Ca2+]i to a level similar to that for control cells. These results suggest that the transient increases in [Ca2+]i were not significantly influenced by the magnetic fields used in this experiment.

9.
Bone Marrow Transplant ; 32(2): 187-94, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12838284

RESUMEN

Delayed recovery of the immune system is a major cause of post-transplant infection. Natural interferon (IFN)-alpha/beta-producing cells (IPC) appear to play a critical role in inducing effective immune responses to a variety of microbial pathogens by producing an enormous amount of IFN-alpha/beta and thereafter by differentiating into dendritic cells. Here, we examined the recovery of IPC as well as other immune cells in 28 patients after allogeneic hematopoietic stem cell transplantation (HSCT) in order to investigate the role of IPC in post-transplant immune reconstitution. In uncomplicated cases, IPC frequency recovered to the lower range of normal values within 30 days after transplantation, resembling the prompt recovery of other cell types in innate immunity. In contrast, the recovery of IPC was profoundly suppressed in the cases with acute graft-versus-host disease (GVHD) and glucocorticoid administration. The patients with lower numbers of IPC were significantly more susceptible to viral infection. The prompt recovery of IPC in uncomplicated cases may contribute to establishing a first line of host defense at the early stage after allogeneic HSCT, whereas the marked suppression of IPC recovery accompanying acute GVHD and glucocorticoid administration may increase the risk of opportunistic infections.


Asunto(s)
Glucocorticoides/administración & dosificación , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Sistema Inmunológico/citología , Interferón-alfa/biosíntesis , Interferón beta/biosíntesis , Leucopoyesis , Enfermedad Aguda , Adolescente , Adulto , Femenino , Enfermedad Injerto contra Huésped/inmunología , Humanos , Sistema Inmunológico/efectos de los fármacos , Sistema Inmunológico/fisiología , Recuento de Leucocitos , Leucocitos/inmunología , Leucopoyesis/efectos de los fármacos , Masculino , Persona de Mediana Edad , Trasplante Homólogo , Virosis/etiología , Virosis/inmunología
10.
J Exp Med ; 194(6): 863-9, 2001 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-11561001

RESUMEN

Toll-like receptors (TLRs) are ancient microbial pattern recognition receptors highly conserved from Drosophila to humans. To investigate if subsets of human dendritic cell precursors (pre-DC), including monocytes (pre-DC1), plasmacytoid DC precursors (pre-DC2), and CD11c(+) immature DCs (imDCs) are developed to recognize different microbes or microbial antigens, we studied their TLR expression and responses to microbial antigens. We demonstrate that whereas monocytes preferentially express TLR 1, 2, 4, 5, and 8, plasmacytoid pre-DC strongly express TLR 7 and 9. In accordance with these TLR expression profiles, monocytes respond to the known microbial ligands for TLR2 (peptidoglycan [PGN], lipoteichoic acid) and TLR4 (lipopolysaccharide), by producing tumor necrosis factor (TNF)-alpha and interleukin (IL)-6. In contrast, plasmacytoid pre-DCs only respond to the microbial TLR9-ligand, CpG-ODNs (oligodeoxynucleotides [ODNs] containing unmethylated CpG motifs), by producing IFN-alpha. CD11c(+) imDCs preferentially express TLR 1, 2, and 3 and respond to TLR 2-ligand PGN by producing large amounts of TNF-alpha, and to viral double-stranded RNA-like molecule poly I:C, by producing IFN-alpha and IL-12. The expression of distinct sets of TLRs and the corresponding difference in reactivity to microbial molecules among subsets of pre-DCs and imDCs support the concept that they have developed through distinct evolutionary pathways to recognize different microbial antigens.


Asunto(s)
Células Dendríticas/metabolismo , Proteínas de Drosophila , Células Madre Hematopoyéticas/metabolismo , Glicoproteínas de Membrana/genética , Receptores de Superficie Celular/genética , Biomarcadores , Citocinas/biosíntesis , Células Dendríticas/citología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Expresión Génica , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/inmunología , Humanos , Lipopolisacáridos/inmunología , Lipopolisacáridos/farmacología , Monocitos/citología , Monocitos/metabolismo , Oligodesoxirribonucleótidos/inmunología , Staphylococcus aureus/inmunología , Receptor Toll-Like 1 , Receptor Toll-Like 2 , Receptor Toll-Like 4 , Receptor Toll-Like 7 , Receptor Toll-Like 9 , Receptores Toll-Like
11.
J Exp Med ; 193(10): 1221-6, 2001 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-11369793

RESUMEN

Natural killer T (NKT) cells are a highly conserved subset of T cells that have been shown to play a critical role in suppressing T helper cell type 1-mediated autoimmune diseases and graft versus host disease in an interleukin (IL)-4-dependent manner. Thus, it is important to understand how the development of IL-4- versus interferon (IFN)-gamma-producing NKT cells is regulated. Here, we show that NKT cells from adult blood and those from cord blood undergo massive expansion in cell numbers (500-70,000-fold) during a 4-wk culture with IL-2, IL-7, phytohemagglutinin, anti-CD3, and anti-CD28 mAbs. Unlike adult NKT cells that preferentially produce both IL-4 and IFN-gamma, neonatal NKT cells preferentially produce IL-4 after polyclonal activation. Addition of type 2 dendritic cells (DC2) enhances the development of neonatal NKT cells into IL-4(+)IFN-gamma(-) NKT2 cells, whereas addition of type 1 dendritic cells (DC1) induces polarization towards IL-4(-)IFN-gamma(+) NKT1 cells. Adult NKT cells display limited plasticity for polarization induced by DC1 or DC2. Thus, newly generated NKT cells may possess the potent ability to develop into IL-4(+)IFN-gamma(-) NKT2 cells in response to appropriate stimuli and may thereafter acquire the tendency to produce both IL-4 and IFN-gamma.


Asunto(s)
Citocinas/metabolismo , Células Dendríticas/inmunología , Células Asesinas Naturales/inmunología , Activación de Linfocitos/inmunología , Subgrupos de Linfocitos T/inmunología , Adulto , Enfermedades Autoinmunes/etiología , Antígenos CD28 , Complejo CD3 , Sangre Fetal/citología , Sangre Fetal/inmunología , Enfermedad Injerto contra Huésped/etiología , Humanos , Recién Nacido , Interferón gamma/metabolismo , Interleucina-2 , Interleucina-4/metabolismo , Interleucina-7 , Fitohemaglutininas
12.
J Immunol ; 166(4): 2291-5, 2001 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-11160284

RESUMEN

Two classes of nucleic acids, bacterial DNA containing unmethylated CpG motifs and dsRNA in viruses, induce the production of type I IFN that contributes to the immunostimulatory effects of these microbial molecules. Thus, it is important to determine which cells produce type I IFN in response to CpG DNA and dsRNA. CD4(+)CD11c(-) type 2 dendritic cell precursors (pre-DC2) were identified as the main producers of type I IFN in human blood in response to viruses. Here we asked whether pre-DC2 also produce type I IFN in response to CpG DNA and dsRNA. Oligodeoxynucleotides containing particular palindromic CpG motifs induced pre-DC2, but not CD11c(+) blood DC or monocytes, to produce IFN-alpha. In contrast, a synthetic dsRNA, polyinosinic polycytidylic-acid, induced CD11c(+) DC, but not pre-DC2 or monocytes, to produce IFN-alphabeta. These data indicate that CpG DNA and polyinosinic-polycytidylic acid stimulate different types of cells to produce type I IFN and that it is important to select oligodeoxynucleotides containing particular CpG motifs to induce pre-DC2 to produce type I IFN, which may play a key role in the strong adjuvant effects of CpG DNA.


Asunto(s)
Células Dendríticas/inmunología , Integrina alfaXbeta2/biosíntesis , Inductores de Interferón/farmacología , Interferón Tipo I/biosíntesis , Oligodesoxirribonucleótidos/farmacología , Poli I-C/farmacología , ARN Bicatenario/farmacología , Células Madre/inmunología , Diferenciación Celular/inmunología , Supervivencia Celular/inmunología , Células Cultivadas , Células Dendríticas/citología , Células Dendríticas/metabolismo , Humanos , Interferón-alfa/biosíntesis , Interferón beta/biosíntesis , Interleucina-12/biosíntesis , Células Mieloides/inmunología , Células Mieloides/metabolismo , Células Madre/citología , Células Madre/metabolismo
13.
Hum Pathol ; 31(9): 1011-7, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11014564

RESUMEN

Combined hepatocellular-cholangiocarcinoma (combined HCC/ CC) is a rare form of liver neoplasms showing both hepatocellular (HCC) and bile duct differentiation (CC). In an attempt to clarify the clonality and genetic/phenotypic relationships in the evolution of these neoplasms, we microdissected multiple HCC and CC foci and studied allelic status of chromosome arms 1p, 1q, 3p, 4q, 5q, 6q, 8p, 9p, 10q, 11q, 13q, 16q, 17p, 17q, 18q, and 22q. Overall, the highest frequency of loss of heterozygosity (LOH) was seen on 4q and 17p, followed by 8p and 16q. Of the 11 cases studied, 3 cases did not show any of the identical allelic losses between HCC and CC foci, indicating the biclonal nature. The remaining 8 cases showed multiple allelic losses shared between both components, strongly suggestive of a single clonal derivation. Moreover, 4 of the 8 cases showed additional or divergent allelic losses at more than 1 chromosomal locus only in HCC and/or CC foci. Thus, this heterogeneity was shown to affect the phenotypic diversity of the tumor. Summarizing the genetic patterns, combined HCC/CC could be classified into the following 3 possibilities: (1) collision tumor in which 2 independent neoplastic clones develop at close proximity; (2) single clonal tumor with homogeneous genetic background in both components--histological diversity is thus a manifestation of divergent differentiation potential of a single clone; (3) single clonal process in which genetic heterogeneity in the process of clonal evolution within the tumor parallels histologic diversity; therefore, the tumor in this category is mainly composed of mosaics of closely related subclones.


Asunto(s)
Neoplasias de los Conductos Biliares/genética , Carcinoma Hepatocelular/genética , Colangiocarcinoma/genética , Neoplasias Hepáticas/genética , Neoplasias Primarias Múltiples/genética , Anciano , Alelos , Neoplasias de los Conductos Biliares/clasificación , Neoplasias de los Conductos Biliares/patología , Carcinoma Hepatocelular/clasificación , Carcinoma Hepatocelular/patología , Separación Celular , Colangiocarcinoma/clasificación , Colangiocarcinoma/patología , Cromosomas Humanos/genética , Células Clonales , ADN de Neoplasias/análisis , Femenino , Humanos , Neoplasias Hepáticas/clasificación , Neoplasias Hepáticas/patología , Pérdida de Heterocigocidad , Masculino , Micromanipulación , Repeticiones de Microsatélite , Persona de Mediana Edad , Neoplasias Primarias Múltiples/clasificación , Neoplasias Primarias Múltiples/patología , Reacción en Cadena de la Polimerasa
15.
J Exp Med ; 192(2): 219-26, 2000 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-10899908

RESUMEN

Innate immune responses to pathogens critically impact the development of adaptive immune responses. However, it is not completely understood how innate immunity controls the initiation of adaptive immunities or how it determines which type of adaptive immunity will be induced to eliminate a given pathogen. Here we show that viral stimulation not only triggers natural interferon (IFN)-alpha/beta-producing cells (IPCs) to produce vast amounts of antiviral IFN-alpha/beta but also induces these cells to differentiate into dendritic cells (DCs). IFN-alpha/beta and tumor necrosis factor alpha produced by virus-activated IPCs act as autocrine survival and DC differentiation factors, respectively. The virus-induced DCs stimulate naive CD4(+) T cells to produce IFN-gamma and interleukin (IL)-10, in contrast to IL-3-induced DCs, which stimulate naive CD4(+) T cells to produce T helper type 2 cytokines IL-4, IL-5, and IL-10. Thus, IPCs may play two master roles in antiviral immune responses: directly inhibiting viral replication by producing large amounts of IFN-alpha/beta, and subsequently triggering adaptive T cell-mediated immunity by differentiating into DCs. IPCs constitute a critical link between innate and adaptive immunity.


Asunto(s)
Inmunidad , Interferón-alfa/fisiología , Interferón beta/fisiología , Diferenciación Celular , Células Cultivadas , Células Dendríticas/fisiología , Humanos , Interleucina-3/farmacología , Simplexvirus/fisiología , Linfocitos T/fisiología , Factor de Necrosis Tumoral alfa/fisiología
16.
Am J Pathol ; 156(6): 2123-33, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10854233

RESUMEN

Genetic alterations of pancreatic intraductal lesions adjacent to invasive ductal carcinoma were investigated. We submitted nine foci of ordinary epithelium, 12 foci of nonpapillary hyperplasia, 12 foci of papillary hyperplasia (pap HP), 66 foci of severe ductal dysplasia, and 27 invasive foci from a total of 10 pancreatic carcinomas for genetic analysis. All foci were individually microdissected and allelic losses of 3p, 4q, 5q, 6q, 8p, 9p, 10q, 11q, 13q, 16q, 17p, and 18q were studied. All invasive and severely dysplastic intraductal foci exhibited loss of heterozygosity (LOH) at more than one chromosomal locus. For each case, allelic loss was frequently observed on 9p (severe ductal dysplasia 90%, invasion 100%), 17p (severe ductal dysplasia 80%, invasion 80%), and 18q (severe ductal dysplasia 88%, invasion 88%). Ninety-four percent of severe ductal dysplasia and 96% of invasive foci had multiple LOH. Seventeen percent of nonpapillary hyperplasia and 33% of pap HP showed LOH. Only one focus of pap HP showed multiple LOH. The patterns of allelic loss identified in severe ductal dysplasia were generally conserved in synchronous infiltrating tumors, supporting the paradigm that infiltrating tumors are clonally derived from severe ductal dysplasia. In eight of 10 cases, however, we found frequent genetic heterogeneity in the intraductal lesion, suggestive of genetic progression or diversion. These findings indicate that invasive pancreatic carcinoma evolves through successive and divergent genetic changes with selection of aggressive subclones in the intraductal component.


Asunto(s)
Carcinoma Ductal de Mama/genética , Neoplasias Pancreáticas/genética , Anciano , Alelos , Carcinoma Ductal de Mama/patología , Mapeo Cromosómico , Femenino , Variación Genética , Humanos , Hiperplasia/genética , Inmunohistoquímica , Pérdida de Heterocigocidad , Masculino , Persona de Mediana Edad , Páncreas/anomalías , Páncreas/patología , Neoplasias Pancreáticas/patología , Proteína p53 Supresora de Tumor/metabolismo
17.
Science ; 284(5421): 1835-7, 1999 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-10364556

RESUMEN

Interferons (IFNs) are the most important cytokines in antiviral immune responses. "Natural IFN-producing cells" (IPCs) in human blood express CD4 and major histocompatibility complex class II proteins, but have not been isolated and further characterized because of their rarity, rapid apoptosis, and lack of lineage markers. Purified IPCs are here shown to be the CD4(+)CD11c- type 2 dendritic cell precursors (pDC2s), which produce 200 to 1000 times more IFN than other blood cells after microbial challenge. pDC2s are thus an effector cell type of the immune system, critical for antiviral and antitumor immune responses.


Asunto(s)
Células Dendríticas/inmunología , Interferón Tipo I/biosíntesis , Interferón-alfa/biosíntesis , Ligando de CD40 , Linaje de la Célula , Separación Celular , Células Cultivadas , Células Dendríticas/citología , Células Dendríticas/ultraestructura , Humanos , Interferón-alfa/genética , Interferón beta/biosíntesis , Interferón beta/genética , Interleucina-3/farmacología , Leucocitos Mononucleares/inmunología , Glicoproteínas de Membrana/farmacología , Orgánulos/ultraestructura , ARN Mensajero/genética , ARN Mensajero/metabolismo , Simplexvirus/inmunología , Células Madre/citología , Células Madre/inmunología
18.
Science ; 283(5405): 1183-6, 1999 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-10024247

RESUMEN

It is not known whether subsets of dendritic cells provide different cytokine microenvironments that determine the differentiation of either type-1 T helper (TH1) or TH2 cells. Human monocyte (pDC1)-derived dendritic cells (DC1) were found to induce TH1 differentiation, whereas dendritic cells (DC2) derived from CD4+CD3-CD11c- plasmacytoid cells (pDC2) induced TH2 differentiation by use of a mechanism unaffected by interleukin-4 (IL-4) or IL-12. The TH2 cytokine IL-4 enhanced DC1 maturation and killed pDC2, an effect potentiated by IL-10 but blocked by CD40 ligand and interferon-gamma. Thus, a negative feedback loop from the mature T helper cells may selectively inhibit prolonged TH1 or TH2 responses by regulating survival of the appropriate dendritic cell subset.


Asunto(s)
Células Dendríticas/citología , Interleucina-4/fisiología , Células TH1/citología , Células Th2/citología , Apoptosis , Antígenos CD40 , Ligando de CD40 , Diferenciación Celular , Linaje de la Célula , Supervivencia Celular , Células Cultivadas , Técnicas de Cocultivo , Células Dendríticas/inmunología , Retroalimentación , Humanos , Interferón gamma/biosíntesis , Interferón gamma/farmacología , Interleucina-12/biosíntesis , Interleucina-12/farmacología , Interleucina-12/fisiología , Interleucina-4/biosíntesis , Interleucina-4/farmacología , Interleucinas/biosíntesis , Interleucinas/farmacología , Activación de Linfocitos , Glicoproteínas de Membrana/farmacología , Células Madre/citología , Células TH1/inmunología , Células Th2/inmunología
19.
Leukemia ; 11 Suppl 3: 318-20, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9209377

RESUMEN

We report here a large series of B-cell neoplasms with regard to rearrangement of the BCL6 gene on chromosome band 3q27. Southern blot analysis using probes from the major translocation cluster (MTC) region of the BCL6 revealed rearrangement in 32 of a total of 222 patients with various subtypes of B-cell neoplasm. In non-Hodgkin's lymphoma (NHL), rearrangements of the BCL6 gene were not closely associated with a specific histopathologic subtype but distributed in subcategories in the Working Formulation. A comparative study between NHL associated either with BCL2 or BCL6 rearrangement showed that advanced disease and bone marrow involvement were more frequent in BCL2(+) NHL. In contrast, extranodal involvement was more frequently observed in the BCL6(+) NHL. The survival curve of BCL6(+) NHL was characterized by a rapid decline followed by a plateau. Of the total of 32 BCL6(+) patients, 6 carried both BCL2 and BCL6 rearrangements, and showed clinicopathological properties of follicular lymphoma. This study suggests that BCL6 rearrangement is primarily associated with large cell lymphoma, and that BCL2(-)BCL6(+) NHL could potentially be curable with modern combination chemotherapy.


Asunto(s)
Cromosomas Humanos Par 3 , Proteínas de Unión al ADN/genética , Reordenamiento Génico , Linfoma de Células B/genética , Linfoma no Hodgkin/genética , Proteínas Proto-Oncogénicas/genética , Factores de Transcripción/genética , Médula Ósea/patología , Bandeo Cromosómico , Mapeo Cromosómico , Humanos , Linfoma de Células B/patología , Linfoma Folicular/genética , Linfoma de Células B Grandes Difuso/genética , Linfoma no Hodgkin/clasificación , Linfoma no Hodgkin/patología , Proteínas Proto-Oncogénicas c-bcl-6 , Dedos de Zinc
20.
Jpn J Cancer Res ; 87(9): 930-7, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8878455

RESUMEN

We investigated mutations of the p53 tumor suppressor gene in B-cell lymphoid neoplasms with reference to oncogene rearrangements associated with specific chromosomal translocations. These included 15 patients with a BCL1/PRAD1 gene rearrangement and/or PRAD1 overexpression, 45 with a BCL2 rearrangement, 2 with a BCL3 rearrangement, 24 with a BCL6 rearrangement, and 6 with both BCL2 and BCL6 rearrangements. Thirty-six patients lacked detectable oncogene rearrangements. Genomic DNA was isolated from involved tissues or leukemic cells obtained at diagnosis and/or at relapse, and established cell lines. Polymerase chain reaction-mediated single-strand conformation polymorphism analysis and direct sequencing were performed to analyze abnormalities of the p53 gene. We detected p53 gene alterations in 18 of 128 patients, representing 21 of the total 151 materials analyzed. In the total of 66 patients with an oncogene rearrangement studied at diagnosis, only one had a mutation; however, 6 of 37 patients studied at relapse showed p53 mutations. Sequential analysis revealed that the p53 mutation was closely associated with transformation from follicular lymphoma to large cell lymphoma, exclusively in BCL2-positive lymphoma cases. Two of 13 mutations observed in oncogene rearrangement-positive cases and cell lines were transitions at CpG dinucleotides. In contrast, the relationship between p53 mutations and clinical behavior in oncogene rearrangement-negative cases was variable; 5 patients including one with indolent follicular lymphoma were positive for p53 mutation at initial presentation, and 2 of the 5 showed prolonged disease-free survival. Our findings suggest that p53 alteration exhibits diverse functions in the development and progression of B-cell tumors related to the presence or absence of oncogene rearrangement, and that chemotherapy-related influences may be involved in the occurrence of progression-associated p53 mutations.


Asunto(s)
Reordenamiento Génico , Genes p53 , Leucemia de Células B/genética , Linfoma de Células B/genética , Mutación , Translocación Genética , Ciclina D1 , Ciclinas/genética , Humanos , Proteínas Oncogénicas/genética , Oncogenes , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Células Tumorales Cultivadas
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