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PURPOSE: This study compared the clinical and radiological results of bone marrow mesenchymal stem cell implantation with traditional simple core decompression (CD) using a matched pair case-control design for osteonecrosis of the humeral head (ONHH) after fracture of the proximal humerus. PATIENTS: We retrospectively reviewed 64 patients who had surgery for ONHH. Thirty patients had been treated with cell therapy between 2010 and October 2015, with 18 patients at pre-collapse stage (8 stages-I, 10 stages-II), and 12 patients at post-collapse stages (7 stages-III and 5 stages-IV). Using a matched pair case-control design, these 30 study patients were compared to 34 other patients who were treated with simple core decompression (CD) without cells (control group). METHODS: The cell therapy group was treated with percutaneous mesenchymal cell (MSCs) injection obtained from bone marrow (BM) concentration. During a mean follow-up duration of 7years (5 to 10years), radiographs performed each year were used to evaluate the radiological results; the Constant score and visual analogue scale were chosen to assess the clinical results. We assessed stage progression, collapse and arthroplasty conversion rate. Survivor rate analysis was performed using these parameters as the primary endpoints. RESULTS: Among the 30 shoulders included in the cell therapy group, three (10%) humeral heads had collapsed at the most recent follow-up, versus 25 (74%) in 34 shoulders after simple core decompression (P<0.0001). As consequence, we observed statistically significant difference (P=0.0001) in the humeral head survival (absence of arthroplasty conversion) rate at the end time point between the cell therapy group (93% survival) and simple core decompression (26% survival). Better results were obtained for early stages (stages I and II) osteonecrosis without collapse at baseline. CONCLUSION: Core decompression with cell therapy was a safe and effective procedure for treatment in the pre-collapse stages of posttraumatic shoulder osteonecrosis and improved the outcome of the disease as compared with simple core decompression without cells.
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Osteonecrosis , Hombro , Tratamiento Basado en Trasplante de Células y Tejidos , Humanos , Osteonecrosis/terapia , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
In diffuse large B-cell lymphomas (DLBCL), a recurrent deletion of the 19p13 region has recently been described. CD70 and TNFSF9 genes are suspected tumor suppressor genes, but previous studies suggest an oncogenic role for CD70. Therefore, we studied the consequences of variation in CD70 copy number and epigenetic modifications on CD70 expression. Copy-number variation was investigated in 144 de novo DLBCL tissues by comparative genomic hybridization array and quantitative multiplex PCR. Gene expression was assessed by quantitative RT-PCR, and CD70 promoter methylation was determined by pyrosequencing. The 19p13.3.2 region was deleted in 21 (14.6%) cases, which allowed the minimal commonly deleted region of 57 Kb that exclusively includes the CD70 gene to be defined. Homozygous deletions were observed in four (2.7%) cases, and acquired single-nucleotide variations of CD70 were detected in nine (6.3%) cases. CD70 was highly expressed in both germinal centre B-cell-like (GCB) and activated B-cell-like (ABC) DLBCL compared to normal tissue, with distinct molecular mechanisms of mRNA expression regulation. A gene dosage effect was observed in the GCB subtype, whereas promoter methylation was the predominant mechanism of down regulation in the ABC subtype. However, high CD70 expression levels correlated to shorter overall survival in both the GCB (P = 0.0021) and the ABC (P =0.0158) subtypes. In conclusion, CD70 is targeted by recurrent deletions, somatic mutations and promoter hypermethylation, but its high level of expression is related to an unfavorable outcome, indicating that this molecule may constitute a potential therapeutic target in selected DLBCL.
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Ligando CD27/genética , Variaciones en el Número de Copia de ADN/genética , Metilación de ADN/genética , Linfoma de Células B Grandes Difuso/genética , Ligando CD27/aislamiento & purificación , Puntos de Rotura del Cromosoma , Deleción Cromosómica , Regulación Neoplásica de la Expresión Génica , Humanos , Hibridación Fluorescente in Situ , Linfoma de Células B Grandes Difuso/patología , Regiones Promotoras Genéticas , Análisis de SupervivenciaRESUMEN
We have shown previously that chromosomal translocations involving chromosome 3q27 and immunoglobulin gene regions are the third most common specific translocations in non-Hodgkin's lymphoma (NHL). We now report the isolation of a gene that is disrupted in two cases by t(3;14) and t(3;4) translocations. The gene (LAZ3) encodes a 79 kDa protein containing six zinc-finger motifs and sharing amino-terminal homology with several transcription factors including the Drosophila tramtrack and Broad-complex genes, both of which are developmental transcription regulators. LAZ3 is transcribed as a 3.8 kb message predominantly in normal adult skeletal muscle and in several NHL carrying 3q27 chromosomal defects. We suggest that it may act as a transcription regulator and play an important role in lymphomagenesis.
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Cromosomas Humanos Par 3/ultraestructura , Proteínas de Unión al ADN/genética , Genes , Linfoma no Hodgkin/genética , Translocación Genética , Dedos de Zinc/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cromosomas Humanos Par 14/ultraestructura , Cromosomas Humanos Par 4/ultraestructura , Drosophila melanogaster/genética , Genes de Inmunoglobulinas , Genes de Insecto , Humanos , Datos de Secuencia Molecular , Proteínas Proto-Oncogénicas c-bcl-6 , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Factores de Transcripción/genéticaRESUMEN
PURPOSE: Handicap evaluation in adults with acquired or progressive congenital visual loss allows for identification of the individual's specific needs and targeted therapy (medical, technical, rehabilitative and psychological). Currently, the subjective dimension of the handicap remains poorly explored in the field of visual loss. Our questionnaire aims to understand the whole of these subjective impacts. It differs from existing quality of life scales in ophthalmology in its approach centered on the process of adaptation, individual resources (technical, cognitive, psychic and environmental), and investigation of the perception of the handicap. The goal of the present study is to validate this questionnaire, which could be used in any adult with a visual handicap, regardless of the extent of the visual loss, its etiology, or the type of treatment or compensatory mechanisms. MATERIALS AND METHODS: The Assessment Questionnaire on the Perception of and Adaptation to Visual Handicap in Adults (QUEPAHVA) is composed of 28 items relating to perception of the visual impairment, its impact, and adaptive resources. They are divided into 3 sub-categories: perception of daily life and relationships (10 items), Perception of visual status and compensatory mechanisms (8 items), and Psychological impact of the visual handicap (10 items). The responses are graded on a Likert scale. Factor analysis and verification of psychometric qualities were performed based on the responses of 446 subjects. The discriminatory validity of the NEI-VFQ 25 was proven with 99 subjects. Reliability over time (mean interval between T1 and T2=49.43 days) was measured in 31 subjects. Sensitivity to change between pre- and post-management (mean interval between T1 and T2=410 days) was tested in 123 subjects. RESULTS: Internal consistency was very good for the global scale (α=.90) as well as for the 3 sub-dimensions (α=.86; α=.79; α=.80). The discriminatory validity was satisfactory (r=.70). This result had to be interpreted as a function of the qualitative specificity of the questionnaire. The questionnaire enjoyed good reproducibility over time with regard to its total score and relatively satisfactory reproducibility with regard to its sub-dimensions. Sensitivity to change was very high and accounted for adaptations to the disability over time. CONCLUSION: The QUEPAHVA displays good psychometric qualities. It constitutes a new means of evaluation. Its potential applications are many. It permits evaluation of the needs of the individual and adaptation of the protocol of care. Its use in institutions may support a step forward in the science of evaluation and continued improvement in quality of care.
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PURPOSE: Handicap evaluation in adults with acquired or progressive congenital visual loss allows for identification of the individual's specific needs and targeted therapy (medical, technical, rehabilitative and psychological). Currently, the subjective dimension of the handicap remains poorly explored in the field of visual loss. Our questionnaire aims to understand the whole of these subjective impacts. It differs from existing quality of life scales in ophthalmology in its approach centered on the process of adaptation, individual resources (technical, cognitive, psychic and environmental), and investigation of the perception of the handicap. The goal of the present study is to validate this questionnaire, which could be used in any adult with a visual handicap, regardless of the extent of the visual loss, its etiology, or the type of treatment or compensatory mechanisms. MATERIALS AND METHODS: The Assessment Questionnaire on the Perception of and Adaptation to Visual Handicap in Adults (QUEPAHVA) is composed of 28 items relating to perception of the visual impairment, its impact, and adaptive resources. They are divided into 3 sub-categories: Perception of daily life and relationships (10 items), Perception of visual status and compensatory mechanisms (8 items), and Psychological impact of the visual handicap (10 items). The responses are graded on a Likert scale. Factor analysis and verification of psychometric qualities were performed based on the responses of 446 subjects. The discriminatory validity of the NEI-VFQ 25 was proven with 99 subjects. Reliability over time (mean interval between T1 and T2=49.43 days) was measured in 31 subjects. Sensitivity to change between pre- and post-management (mean interval between T1 and T2=410 days) was tested in 123 subjects. RESULTS: Internal consistency was very good for the global scale (α=.90) as well as for the 3 sub-dimensions (α=.86; α=.79; α=.80). The discriminatory validity was satisfactory (r=.70). This result had to be interpreted as a function of the qualitative specificity of the questionnaire. The questionnaire enjoyed good reproducibility over time with regard to its total score and relatively satisfactory reproducibility with regard to its sub-dimensions. Sensitivity to change was very high and accounted for adaptations to the disability over time. CONCLUSION: The QUEPAHVA displays good psychometric qualities. It constitutes a new means of evaluation. Its potential applications are many. It permits evaluation of the needs of the individual and adaptation of the protocol of care. Its use in institutions may support a step forward in the science of evaluation and continued improvement in quality of care.
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Adaptación Fisiológica/fisiología , Personas con Discapacidad/psicología , Percepción , Psicometría/métodos , Encuestas y Cuestionarios , Trastornos de la Visión/psicología , Adulto , Anciano , Anciano de 80 o más Años , Conducta , Evaluación de la Discapacidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicometría/normas , Sistemas de Apoyo Psicosocial , Calidad de Vida/psicología , Reproducibilidad de los Resultados , Trastornos de la Visión/diagnóstico , Adulto JovenRESUMEN
Four chromosomal defects associated with outcome are commonly evaluated by fluorescent in situ hybridization (FISH) in chronic lymphocytic leukemia (CLL), namely deletions of the 13q13-q14, 11q22 and 17p13 regions and trisomy 12. In this study, we compared a quantitative PCR method--quantitative multiplex PCR of short fluorescent fragment (QMPSF)--with FISH for the detection of these acquired aneuploidies in a series of 110 patients with Binet stage A CLL. Genes located in the deleted or gained regions were selected as target genes and amplified using a method based on the simultaneous amplification of short fluorescent genomic fragments under quantitative conditions. A chromosomal imbalance involving one or several of the four loci was detected by either method in 72 patients (65%). A chromosome 13 deletion was present in 61 patients (54%), a 11q22 deletion in nine (8%), a trisomy 12 in nine and a 17p deletion in one. FISH and QMPSF results were identical for 103 out of 110 patients and discrepancies could be explained in most cases. This study demonstrates that a quantitative multiplex PCR represents a cost-effective method that could replace FISH in CLL patients. However, although QMPSF is perfectly adapted to the detection of primary defects, care should be taken when searching for clonal evolutions present in a small proportion of tumor cells.
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Aneuploidia , Hibridación Fluorescente in Situ/normas , Leucemia Linfocítica Crónica de Células B/genética , Reacción en Cadena de la Polimerasa/métodos , Anciano , Anciano de 80 o más Años , Deleción Cromosómica , Cromosomas Humanos Par 11 , Cromosomas Humanos Par 13 , Cromosomas Humanos Par 16 , Análisis Costo-Beneficio , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/diagnóstico , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/normas , Pronóstico , TrisomíaRESUMEN
Chromosomal translocations joining the immunoglobulin (IG) and MYC genes have been extensively reported in Burkitt's and non-Burkitt's lymphomas but data concerning MYC rearrangements with non-IG partners are scarce. In this study, 8q24 breakpoints from 17 B-cell lymphomas involving non-IG loci were mapped by fluorescence in situ hybridization (FISH). In seven cases the breakpoint was inside a small region encompassing MYC: in one t(7;8)(p12;q24) and two t(3;8)(q27;q24), it was telomeric to MYC whereas in four cases, one t(2;8)(p15;q24) and three t(8;9)(q24;p13) it was located in a 85 kb region encompassing MYC. In these seven cases, partner regions identified by FISH contained genes known to be involved in lymphomagenesis, namely BCL6, BCL11A, PAX5 and IKAROS. Breakpoints were cloned in two t(8;9)(q24;p13), 2.5 and 7 kb downstream from MYC and several hundred kb 5' to PAX5 on chromosome 9, joining MYC to ZCCHC7 and to ZBTB5 exon 2, two genes encoding zinc-finger proteins. In these seven cases, MYC expression measured by quantitative reverse transcription-polymerase chain reaction (RT-PCR) was significantly higher when compared to that of patients without 8q24 rearrangement (P=0.006). These results suggest that these rearrangements are the consequence of a non-random process targeting MYC together with non-IG genes involved in lymphocyte differentiation and lymphoma progression.
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Rotura Cromosómica , Cromosomas Humanos Par 8/genética , Genes myc , Linfoma de Células B/genética , Translocación Genética/genética , Adulto , Anciano , Anciano de 80 o más Años , Secuencia de Bases , Linfoma de Burkitt/genética , Proteínas Portadoras/genética , Transformación Celular Neoplásica/genética , Cromosomas Humanos Par 2/genética , Cromosomas Humanos Par 2/ultraestructura , Cromosomas Humanos Par 3/genética , Cromosomas Humanos Par 3/ultraestructura , Cromosomas Humanos Par 7/genética , Cromosomas Humanos Par 7/ultraestructura , Cromosomas Humanos Par 8/ultraestructura , Cromosomas Humanos Par 9/genética , Cromosomas Humanos Par 9/ultraestructura , Proteínas de Unión al ADN/genética , Femenino , Humanos , Factor de Transcripción Ikaros/genética , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Proteínas Nucleares/genética , Factor de Transcripción PAX5/genética , Proteínas Proto-Oncogénicas c-bcl-6 , Proteínas Represoras , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Polymerase chain reaction (PCR) assessment of clonal T-cell receptor (TCR) and immunoglobulin (Ig) gene rearrangements is an important diagnostic tool in mature T-cell neoplasms. However, lack of standardized primers and PCR protocols has hampered comparability of data in previous clonality studies. To obtain reference values for Ig/TCR rearrangement patterns, 19 European laboratories investigated 188 T-cell malignancies belonging to five World Health Organization-defined entities. The TCR/Ig spectrum of each sample was analyzed in duplicate in two different laboratories using the standardized BIOMED-2 PCR multiplex tubes accompanied by international pathology panel review. TCR clonality was detected in 99% (143/145) of all definite cases of T-cell prolymphocytic leukemia, T-cell large granular lymphocytic leukemia, peripheral T-cell lymphoma (unspecified) and angioimmunoblastic T-cell lymphoma (AILT), whereas nine of 43 anaplastic large cell lymphomas did not show clonal TCR rearrangements. Combined use of TCRB and TCRG genes revealed two or more clonal signals in 95% of all TCR clonal cases. Ig clonality was mostly restricted to AILT. Our study indicates that the BIOMED-2 multiplex PCR tubes provide a powerful strategy for clonality assessment in T-cell malignancies assisting the firm diagnosis of T-cell neoplasms. The detected TCR gene rearrangements can also be used as PCR targets for monitoring of minimal residual disease.
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Genes de Inmunoglobulinas , Leucemia de Células T/genética , Linfoma de Células T/genética , Reacción en Cadena de la Polimerasa/métodos , Receptores de Antígenos de Linfocitos T/genética , Amplificación de Genes , Reordenamiento Génico , Genotipo , Humanos , Inmunohistoquímica , Leucemia Prolinfocítica/genética , Leucemia Prolinfocítica/inmunología , Leucemia Prolinfocítica/patología , Leucemia de Células T/inmunología , Leucemia de Células T/patología , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/inmunología , Linfoma de Células B Grandes Difuso/patología , Linfoma de Células T/inmunología , Linfoma de Células T/patología , Linfocitos T/inmunologíaRESUMEN
Polymerase chain reaction (PCR) assessment of clonal immunoglobulin (Ig) and T-cell receptor (TCR) gene rearrangements is an important diagnostic tool in mature B-cell neoplasms. However, lack of standardized PCR protocols resulting in a high level of false negativity has hampered comparability of data in previous clonality studies. In order to address these problems, 22 European laboratories investigated the Ig/TCR rearrangement patterns as well as t(14;18) and t(11;14) translocations of 369 B-cell malignancies belonging to five WHO-defined entities using the standardized BIOMED-2 multiplex PCR tubes accompanied by international pathology panel review. B-cell clonality was detected by combined use of the IGH and IGK multiplex PCR assays in all 260 definitive cases of B-cell chronic lymphocytic leukemia (n=56), mantle cell lymphoma (n=54), marginal zone lymphoma (n=41) and follicular lymphoma (n=109). Two of 109 cases of diffuse large B-cell lymphoma showed no detectable clonal marker. The use of these techniques to assign cell lineage should be treated with caution as additional clonal TCR gene rearrangements were frequently detected in all disease categories. Our study indicates that the BIOMED-2 multiplex PCR assays provide a powerful strategy for clonality assessment in B-cell malignancies resulting in high Ig clonality detection rates particularly when IGH and IGK strategies are combined.
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Genes de Inmunoglobulinas , Leucemia de Células B/genética , Linfoma de Células B/genética , Reacción en Cadena de la Polimerasa/métodos , Cromosomas Humanos Par 11 , Cromosomas Humanos Par 14 , Cromosomas Humanos Par 18 , Reordenamiento Génico , Genotipo , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Leucemia de Células B/diagnóstico , Leucemia de Células B/inmunología , Linfoma de Células B/diagnóstico , Linfoma de Células B/inmunología , Receptores de Antígenos de Linfocitos T/genética , Translocación GenéticaRESUMEN
The t(3;14)(q27;q32) is the most common translocation involving BCL6 in B-cell lymphoma. Although this translocation was predominantly associated with diffuse large B-cell lymphoma (DLBCL), recent studies have shown that it can also be found in follicular lymphomas (FL), often associated with a large cell component. To further investigate the relationship that might exist between this translocation and the phenotype of the tumors, we studied 34 lymphomas with a t(3;14)(q27;q32). Twenty cases were DLBCL, 14 FL and most cases, regardless of histology, were negative for the expression of CD10 (26/32, 81%). We identified the IGH switch region involved in the translocation for 32 cases. Our data indicate that in DLBCL most breakpoints involve the switch mu (17/19; 89%), whereas in FL most involve a switch gamma (9/13; 70%) (P=0.0016, Fisher's exact test). This correlation between the histology and the structure of the translocated allele suggests that the lymphomas with Smu and Sgamma translocations may originate from different cells, or that the substituted regulatory regions that come to deregulate BCL6 may affect the presentation of the disease.
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Cromosomas Humanos Par 14 , Cromosomas Humanos Par 3 , Cadenas Pesadas de Inmunoglobulina/genética , Linfoma de Células B/genética , Linfoma de Células B/patología , Translocación Genética , Marcadores Genéticos , HumanosRESUMEN
Adult patients with acute lymphoblastic leukemia (ALL) and t(1;19)/E2A-PBX1 or t(4;11)/MLL-AF4 have a poor outcome. We have evaluated the impact of an intensified post-remission therapy using a high-dose chemotherapy course followed by allogeneic or autologous SCT on the outcome of 58 patients with t(1;19)/E2A-PBX1 (E2A group, n=24) or t(4;11)/MLL-AF4 (MLL group, n=34) treated in the LALA-94 multicenter prospective study. Patients in the MLL group had higher WBC counts and more frequent DIC. CR rates achieved by MLL and E2A groups were similar to other B-cell ALL (87, 82 and 86% respectively). While in CR, patients with a donor were assigned to alloSCT (n=22), the remaining patients with were randomized between autoSCT (n=15) or chemotherapy (n=8). Five-year overall survival was 31 and 45% for E2A and MLL groups, respectively. In both groups, DFS was higher in the alloSCT arm as compared to autoSCT and chemotherapy arms. The results of this study show that chemotherapy intensification did not overcome the poor prognosis of adults with t(1;19)/E2A-PBX1. Allogeneic SCT should thus be offered in first CR to patients with t(1;19)/E2A-PBX1 or t(4;11)/MLL-AF4. New therapeutic approaches are needed for patients without donor.
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Linfoma de Burkitt/genética , Linfoma de Burkitt/terapia , Trasplante de Células Madre Hematopoyéticas , Translocación Genética , Adolescente , Adulto , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Cromosomas Humanos Par 1/genética , Cromosomas Humanos Par 11/genética , Cromosomas Humanos Par 19/genética , Cromosomas Humanos Par 4/genética , Proteínas de Unión al ADN/genética , Femenino , N-Metiltransferasa de Histona-Lisina , Humanos , Masculino , Persona de Mediana Edad , Proteína de la Leucemia Mieloide-Linfoide/genética , Proteínas Nucleares/genética , Factor de Transcripción 1 de la Leucemia de Células Pre-B , Estudios Prospectivos , Proteínas Proto-Oncogénicas/genética , Factores de Elongación Transcripcional , Trasplante HomólogoRESUMEN
INTRODUCTION: Since knee osteoarthritis is unicompartmental in most cases, a knee osteotomy is the most logical solution to limit degeneration of the arthritic compartment, thereby delaying knee arthroplasty. Younger patients have high functional demands. The purpose of this study was to evaluate the return to sports and quality of life after high tibial osteotomy (HTO) in athletic patients less than 60 years of age. The hypothesis was that patients can return to sports within 1 year of HTO. MATERIALS AND METHODS: A single-centre, retrospective study was performed of 30 patients under 60 years of age with medial tibiofemoral osteoarthritis and no history of surgery or trauma who underwent HTO between January 2014 and August 2015. The primary endpoint was the return to sport at 1 year based on the Tegner score. Secondary endpoints were the subjective IKDC score, Lysholm score and SF-36. RESULTS: The mean follow-up was 1.3 years [1-1.5] and no patients were lost to follow-up. All the patients had returned to sports at 1 year: 73.3% at their pre-surgery level (before the pain started) and 23.3% at a higher level. Their quality of life was significantly improved according to the SF-36 questionnaire: 65.3% pre-operatively compared with 72.5% postoperatively (P=0.01). The preoperative and 1-year postoperative scores were comparable for the Tegner (P=0.167), IKDC (P=0.093) and Lysholm (P=0.061). CONCLUSION: HTO allows patients to resume their sports activities within 1 year of surgery and significantly improves their quality of life. LEVEL OF EVIDENCE: Level IV - Retrospective cohort study.
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Osteoartritis de la Rodilla/cirugía , Osteotomía/métodos , Calidad de Vida , Volver al Deporte , Tibia/cirugía , Adulto , Factores de Edad , Femenino , Estudios de Seguimiento , Humanos , Escala de Puntuación de Rodilla de Lysholm , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Estudios Retrospectivos , Encuestas y CuestionariosRESUMEN
Genetic modifications of the BCL6 gene in lymphoma include translocations, deletions, and somatic mutations (SM) of the 5' noncoding region. Three single-nucleotide polymorphisms (SNPs) of the major mutation cluster region (MMC) have been reported, including two substitutions (397G/C, 502G/A) and one deletion (520DeltaT). Clinical and biological relevance of these SNPs are unknown. Based on a case-control study, BCL6 SNPs frequencies were assessed in 97 t(14;18) follicular lymphomas (FL) and in 54 lymphomas with 3q27 rearrangement. Allele frequencies were similar in the FL and controls groups. The 397 G/C genotype was correlated to a higher-grade transformation risk (P=0.02). SM were observed in 39.1% of FL and were characterized by a clustering distribution (hot spots spanning position 420-435, 106-127, and 590-600). No correlation between genotypes or acquired mutational status and BCL6 expression was demonstrated. However, gel mobility-shift assays, using SNPs containing probes show results representative for protein/DNA complexes. This study demonstrates that the first BCL6 intron is a highly variable region as a consequence of both SNP and SM, which may contribute to biology and outcome of FL.
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Cromosomas Humanos Par 3/genética , Proteínas de Unión al ADN/genética , Intrones/genética , Linfoma Folicular/genética , Mutación , Polimorfismo de Nucleótido Simple/genética , Proteínas Proto-Oncogénicas/genética , Factores de Transcripción/genética , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Cromosomas Humanos Par 14/genética , Cromosomas Humanos Par 18/genética , ADN/genética , ADN/metabolismo , Análisis Mutacional de ADN , Proteínas de Unión al ADN/metabolismo , Ensayo de Cambio de Movilidad Electroforética , Femenino , Regulación Neoplásica de la Expresión Génica , Reordenamiento Génico , Humanos , Linfoma Folicular/metabolismo , Linfoma de Células B Grandes Difuso/genética , Masculino , Persona de Mediana Edad , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-6 , Factores de Transcripción/metabolismoRESUMEN
The LAZ3/BCL6 gene encoding a Zinc-finger nuclear protein is altered in Non-Hodgkin's Lymphomas (NHLs) by translocations, mutations and/or deletions clustered in its 5' non coding region, in a 3.3 Kbp EcoRI fragment which thus defines the Major Translocation Cluster (MTC). In the present study, we describe at the molecular level the deletions found in the MTC of two (NHL) cases using, (i) DNA obtained from a patient (GUI) with a monosomy 3 and three microdeletions of 101, 22, 25 bp in its unique untranslocated 3q27 allele; (ii) a cell line derived from a patient (VAL) carrying a t(3;4) (q27;p11) translocation and a 2.4 Kbp deletion in the untranslocated allele. As the MTC is recurrently subject to alterations, we have cloned and sequenced the murine equivalent of the human MTC and promoter region in an attempt to identify sequences well conserved in mammals that may be thus important for the LAZ3/BCL6 gene regulation. We show that the human and mouse 5' upstream regions of the LAZ3/BCL6 gene although mainly intronic share a particularly high homology of 79% on the overall sequence. Strikingly, the small sequences which are deleted in patient (GUI) are highly conserved (81%, 100% and 92% respectively). Furthermore, they may play a role in the pathogenesis since proteins prepared from B cell lines and HeLa nuclear extracts bind to these sequences in gel retardation assays. Although a large part of this region is intronic, the high conservation of its sequence and the frequency of alterations in NHLs suggest that they are likely to be significant for the regulation of the LAZ3/BCL6 gene.
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Cromosomas Humanos Par 3 , Proteínas de Unión al ADN/genética , Linfoma no Hodgkin/genética , Familia de Multigenes , Proteínas Proto-Oncogénicas/genética , Factores de Transcripción/genética , Translocación Genética , Dedos de Zinc , Animales , Secuencia de Bases , Secuencia Conservada , Eliminación de Gen , Reordenamiento Génico , Células HeLa , Humanos , Ratones , Datos de Secuencia Molecular , Proteínas Proto-Oncogénicas c-bcl-6 , Alineación de SecuenciaRESUMEN
We have previously shown that the LAZ3/BCL6 gene encoding a potential transcription factor, is disrupted in B-diffuse large cell non-Hodgkin's lymphomas (NHL) with 3q27 chromosomal abnormalities involving the immunoglobulin (IG) genes. However, LAZ3 rearrangement also occurs in NHL bearing 3q27 translocations without involvement of the IG genes: for example the VAl cell line exhibits t(3;4)(q27;p11). In the present work we have used a RT-PCR method to detect and to sequence the LAZ3 mRNA products from the VAL cell line. We report that the consequence of the t(3;4) is the expression of a chimeric transcript of LAZ3 with a new gene encoding a small G-like protein, termed TTF (Translocation Three Four). Nucleotide sequence analysis of a 1.4 kb cDNA predicts that the TTF gene encodes a protein of 191 amino-acids similar to members of the RAS superfamily including HRAS (27% identical), RAB1A (30% identical) and RHO proteins: the human RAC1, RHOB and CDC42Hs proteins (respectively 43, 44 and 45% identical) and the yeast RHO2 protein (44% identical). Unlike most other small G proteins which are expressed ubiquitously, TTF was transcribed only in hemopoietic cells as a 2.2 kb transcript. TTF may define a new subgroup of RHO-like proteins.
Asunto(s)
Clonación Molecular , Proteínas de Unión al ADN/genética , Proteínas de Unión al GTP/genética , Factores de Transcripción/genética , Translocación Genética , Secuencia de Aminoácidos , Secuencia de Bases , Cromosomas Humanos Par 3 , Cromosomas Humanos Par 4 , ADN Complementario , Humanos , Datos de Secuencia Molecular , Filogenia , Proteínas Proto-Oncogénicas c-bcl-6 , ARN Mensajero/genética , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Células Tumorales CultivadasRESUMEN
Through two consecutive trials, a policy that considered allogeneic stem cell transplantation (SCT) from a sibling donor in second rather than first complete remission (CR) in selected younger patients with acute myeloid leukemia (AML) with t(8;21)/inv(16) (core binding factor (CBF) group) or a normal karyotype (NN group) was followed by Acute Leukemia French Association (ALFA) centers. The outcome of 92 of these patients in first relapse (32 CBF, 60 NN) was reviewed with the aim of validating this strategy. The presence of an FLT3 internal tandem duplication (ITD) was retrospectively assessed in 50 patients. A total of 61 patients (66%) reached a second CR. Donor availability was an independent prognostic factor for survival in the whole patient population as well as in the CBF subset, but not in NN patients, further supporting this strategy for CBF-AMLs. In NN patients, FLT3-ITD was the main bad-prognosis factor for second CR achievement and survival, leading to consider SCT earlier, at least in FLT3-ITD patients with a donor.
Asunto(s)
Leucemia Mieloide Aguda/terapia , Trasplante de Células Madre/métodos , Trasplante Homólogo/métodos , Adulto , Duplicación de Gen , Humanos , Cariotipificación , Leucemia Mieloide Aguda/mortalidad , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Pronóstico , Modelos de Riesgos Proporcionales , Proteínas Proto-Oncogénicas/genética , Proteínas Tirosina Quinasas Receptoras/genética , Recurrencia , Inducción de Remisión , Estudios Retrospectivos , Riesgo , Hermanos , Factores de Tiempo , Donantes de Tejidos , Translocación Genética , Resultado del Tratamiento , Tirosina Quinasa 3 Similar a fmsRESUMEN
Chromosomal abnormalities of erythroleukemia (EL) are often described as complex and unspecific. A retrospective study of 75 EL defined following the WHO classification was performed by the Groupe Francophone de Cytogénétique Hématologique (GFCH) in order to reexamine the cytogenetics of this infrequent leukemia subtype. Clonal chromosomal abnormalities were found in 57 patients (76%), distributed in 4 subgroups according to their ploidy status: pseudodiploid (16%), hypodiploid (47%), hyperdiploid (19%), and 18% mixed cases associating 2 different clones (hypodiploid+hyperdiploid) or (pseudodiploid+hyperdiploid). Complex rearrangements and hypodiploid chromosome number were widely dominant (50%). Partial or entire monosomies represented 56% of abnormalities. Chromosomes 5 and 7 were the most frequently involved (41 and 33 times, respectively), followed by chromosomes 8, 16, and 21 (19 times each). Unbalanced abnormalities were more frequent than balanced. All these kinds of abnormalities were observed in de novo as well as in secondary EL. Four out of 7 cases of "pure erythroid" leukemia were associated with a BCR-ABL fusion. Lastly, no chromosome abnormality specific to EL could be established. However, the large overlap of chromosomal abnormality patterns of EL (pure erythroid form excepted) and refractory anemia with excess of blasts in transformation (RAEB-t) favors the hypothesis of similarities between these 2 hematologic disorders.
Asunto(s)
Aberraciones Cromosómicas , Leucemia Eritroblástica Aguda/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Cromosomas Humanos , Humanos , Persona de Mediana Edad , Ploidias , Estudios Retrospectivos , Análisis de SupervivenciaRESUMEN
Translocation t(3;22)(q27;q11) has recently been recognized as a recurrent abnormality in non-Hodgkin's malignant lymphoma (NHL). A new gene, LAZ3, has been shown to be involved in NHL with 3q27 rearrangement. Two patients with B-cell NHL were studied by chromosome painting and Southern blot analysis. Fluorescence in situ hybridization to metaphase chromosomes was shown to be an easy way to detect the chromosomal abnormality even in metaphase cells with poorly defined chromosomes. The gene LAZ3 was rearranged in one patient in the 'major translocation cluster region'. The comigration of rearranged LAZ3 and of IGL bands suggests that the translocation resulted in the juxtaposition of the two genes. This juxtaposition makes possible a potential deregulation of the LAZ3 gene expression, as previously shown for the MYC and BCL2 genes in Burkitt and follicular lymphoma translocations.
Asunto(s)
Cromosomas Humanos Par 22 , Cromosomas Humanos Par 3 , Linfoma no Hodgkin/genética , Translocación Genética , Anciano , Southern Blotting , Mapeo Cromosómico , Femenino , Reordenamiento Génico , Genes Relacionados con las Neoplasias , Humanos , Hibridación Fluorescente in Situ , Linfoma de Células B/genética , Linfoma Folicular/genética , Persona de Mediana Edad , Dedos de Zinc/genéticaRESUMEN
The Evi-1 zinc-finger protein gene is normally not expressed in hematopoietic cells. However, high Evi-1 mRNA expression has been reported in mouse myeloblastic leukemias, due to transcriptional activation by proviral integration in either the Fim-3 or Evi-1 loci. The human Evi-1 gene is located on chromosome 3q24-q28. In this paper three examples are presented of human acute myelogenous leukemias presenting common characteristics: (i) high Evi-1 mRNA expression; (ii) chromosomal abnormalities t(3;3)(q21;q26) or inv(3;3)(q21-22;q26); and (iii) high platelet counts and dystrophic megakaryocytes. Thirty-four other patients with hematological malignancies, among which 11 had chromosomal rearrangements in the 3q24-q28 region did not exhibit such abnormalities. Of the 13 permanent hemopoietic cell lines tested, Evi-1 RNA expression was found in HEL and K-562 cell lines. Weak Evi-1 expression was also seen in fibroblasts and lung cells. This expression was affected neither in skin cells from a patient with a 3q27 constitutional translocation nor in a lung epithelioma cell line containing an excess of chromosome 3 long arm. Ectopic strong expression of Evi-1 in human leukemias could define an uncommon subclass of acute myelogenous leukemias with translocations involving the 3q25-28 chromosomal domain and abnormal megakaryopoiesis.
Asunto(s)
Leucemia/genética , Adulto , Cromosomas Humanos Par 3 , Sondas de ADN , Femenino , Reordenamiento Génico , Humanos , Leucemia Mieloide Aguda/genética , Linfoma/genética , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocación Genética , Células Tumorales CultivadasRESUMEN
Loss of MHC class II expression in B-cell lymphoma has been associated with a higher tumorigenicity resulting from lower titers of tumor-infiltrating lymphocytes. This report aims towards the identification of the molecular mechanism leading to defective MHC class II expression in a B-cell lymphoma cell line, Rec-1. We evidenced a coordinated alteration of HLA-D gene transcription, reminiscent of B lymphoblastoid cell lines from patients with MHC class II deficiency. Genetic complementation performed between these cell lines and the lymphoma cells indicated that Rec-1 is altered in the MHC2TA gene. MHC2TA encodes the class II transactivator (CIITA), the master regulator of HLA-D gene expression. However, the coding sequence of the Rec-1 CIITA transcript did not reveal any mutation that could hamper the activity of the encoded protein. In agreement with the genetic complementation analysis, we evidenced a highly residual CIITA protein expression in the Rec-1 cell line resulting from a transcriptional defect affecting MHC2TA expression. Anti-HLA-DR monoclonal antibody treatment has proved efficient in the destruction of B lymphoma cells. Our data indicate that the appearance of variants losing CIITA, and thereby HLA-DR, expression will require a thorough monitoring during such immunotherapy protocols.