ABSTRACT
Mantle cell lymphoma (MCL) is a well defined lymphoid neoplasm genetically characterized by the t(11;14)(q13;q32). Telomeres play an essential role in preserving chromosomal integrity and genomic stability; their shortening can lead to telomere dysfunction and chromosomal instability, a critical factor in cancer development. In this study, telomere length (TL) measured by terminal restriction fragments (TRF) assay in DNA samples of tumor cells from 20 patients with MCL was evaluated. Results were correlated with clinical, morphologic and cytogenetic characteristics. In all cases, the presence of the CCND1/IGH@ rearrangement was confirmed by fluorescence in situ hybridization and/or PCR analysis. TL in total MCL patients revealed a mean TRF value (4.51 +/- 0.79 kb) significantly shorter than those observed in controls (7.49 +/- 1.94 kb) (P < 0.001); 30% of patients had TL shorter than 4.0 kb. TRF length was not associated with patients age (P = 0.07; r = 0.17) nor with sex (females: 4.33 +/- 0.51 kb and males: 4.57 +/- 0.85 kb; P = 0.63). No significant differences were found between patients studied at diagnosis (13) (4.44 +/- 0.81 kb) respect to those analyzed at relapse (7) (4.63 +/- 0.82 kb) (P = 0.53). In addition, we compared patients with (4.84 +/- 1.09 kb) and without (4.40 +/- 0.68 kb) complex karyotypes (P = 0.45) and cases with typical morphology (4.48 +/- 0.79 kb) vs. blastoid variant (4.63 +/- 1.04 kb) (P = 0.83), and no significant differences between them were found. Although the number of cases of our series is not large, our results showed that TL reduction in MCL is independent of the clinical characteristics, morphology and karyotype.
Subject(s)
Lymphoma, Mantle-Cell/genetics , Telomere/genetics , Adult , Aged , Aged, 80 and over , Chromosomes, Human, Pair 11 , Chromosomes, Human, Pair 14 , Female , Humans , Lymphoma, Mantle-Cell/diagnosis , Lymphoma, Mantle-Cell/pathology , Lymphoma, Mantle-Cell/therapy , Male , Middle Aged , Oncogene Proteins, Fusion/genetics , Recurrence , Sex Factors , Translocation, Genetic/geneticsABSTRACT
Chronic myeloid leukemia (CML) is characterized by the translocation t(9;22)(q34;q11) [Philadelphia (Ph) chromosome). Although not frequently occurring, additional chromosome abnormalities (ACAs) can be detected at diagnosis and a number have been associated with an adverse cytogenetic and molecular outcome. The present study reports a case of CML presenting with the translocation t(1;11)(q21;q23) and a cryptic Ph chromosome. The presence of ACAs could generate greater genetic instability, promoting the emergence of further alterations. The present findings suggest that t(1;11)(q21;q23) can prevent a good response to tyrosine kinase inhibitor (TKI) therapy developing a primary resistance. In the present patient, at a recent follow-up, the T315I mutation was detected. This mutation confers full resistance to all available TKI, except ponatinib, which was not a therapeutic option due to comorbidities.
ABSTRACT
Telomere length based on terminal restriction fragment (TRF) assay was evaluated in cells of bone marrow, lymph node, or both from 53 non-Hodgkin lymphoma (NHL) patients: 44 with follicular lymphoma (FL) and 9 with secondary diffuse large B-cell lymphoma (S-DLBCL) to FL. The TRF data were correlated with BCL2 gene rearrangement evaluated by nested and long-distance polymerase chain reaction approaches. Peripheral blood cells from 12 healthy donors were studied as controls. Both groups of NHL patients revealed significant telomere shortening compared with controls (8.50 +/- 0.50 kb; P < 0.001), with significantly shorter TRFs in S-DLBCL (3.49 +/- 0.26 kb) than in FL cases (4.09 +/- 0.12 kb; P = 0.047). Patients carrying BCL2 gene rearrangements showed longer telomere length (4.19 +/- 0.14 kb) than those without (3.51 +/- 0.14 kb; P = 0.05). Among patients with FL, telomere length was shortest in patients without t(14;18), intermediate when breakpoints occurred in the minor breakpoint cluster region (3.97 +/- 0.33 kb), and greater when breakpoints occurred in the major breakpoint region (MBR) (4.24 +/- 0.15 kb), with significant differences between MBR and BCL2-negative cases (P = 0.033). Our findings support the existence of alternative genetic pathways involved in the origin of these FL subsets. Even though the number of S-DLBCL cases was small, they showed the shortest telomere length, suggesting that this parameter reflects another genetic alteration involved in the progression from FL to a higher-grade lymphoma.
Subject(s)
Gene Rearrangement , Lymphoma, Non-Hodgkin/pathology , Proto-Oncogene Proteins c-bcl-2/genetics , Telomere/genetics , Adult , Aged , DNA, Neoplasm/genetics , DNA, Neoplasm/metabolism , Deoxyribonucleases, Type II Site-Specific/metabolism , Electrophoresis, Agar Gel , Female , Humans , Lymphoma, Non-Hodgkin/genetics , Male , Middle AgedABSTRACT
Inversions are infrequent events in hematological malignancies. We here report the cytogenetic, fluorescence in situ hybridization (FISH), and molecular studies of 2 patients diagnosed with mantle cell lymphoma (MCL) that showed inversions of chromosomes 2 and 6 as part of complex karyotypes. Both patients showed a cytogenetically identical inv(6)(p23q11) detected as a secondary aberration. In addition, both patients had a derivative chromosome 2 which originated by partial deletion of the short arm and a pericentric inversion with different breakpoints on the long arm: der(2)del(2)(p21)inv(2)(p21q11) and der(2)del(2)(p21)inv(2)(p21q13), respectively. The presence of t(11;14)(q13;q32) was confirmed by interphase FISH and by molecular study. Residual normal cells were found in both cases. The patients showed a different clinical evolution with a poor outcome for one case and a favorable course of the disease for the other one. The review of the literature in MCL showed a total of 9 inversions affecting different chromosomes. Considering that inversions are very infrequent events in MCL, our findings could be important for detecting genes potentially involved in development and/or progression of this aggressive non-Hodgkin lymphoma subtype.
Subject(s)
Chromosome Inversion , Chromosomes, Human, Pair 2 , Chromosomes, Human, Pair 6 , Lymphoma, Mantle-Cell/genetics , Adult , Aged , Aged, 80 and over , Chromosomes, Human, Pair 2/ultrastructure , Chromosomes, Human, Pair 6/ultrastructure , Female , Humans , In Situ Hybridization, Fluorescence , Karyotyping , Lymphoma, Mantle-Cell/diagnosis , Male , Polymerase Chain ReactionSubject(s)
Fusion Proteins, bcr-abl/genetics , Mutation , Protein Interaction Domains and Motifs/genetics , Adult , Amino Acid Substitution , Codon , Drug Resistance, Neoplasm/genetics , Fusion Proteins, bcr-abl/chemistry , Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Male , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic useSubject(s)
Genes, bcl-2 , Lymphoma, Follicular/genetics , Lymphoma, Follicular/pathology , Adult , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Base Sequence , Chromosome Breakpoints , Clone Cells , Dexamethasone/administration & dosage , Female , Gene Rearrangement , Humans , Lymphoma, Follicular/drug therapy , Mitoxantrone/administration & dosage , Molecular Sequence Data , Neoplasm Staging , Polymerase Chain Reaction , Vidarabine/administration & dosage , Vidarabine/analogs & derivativesABSTRACT
The t(14;18)(q32;q21) is the most frequent cytogenetic abnormality observed in follicular lymphoma (FL), but also occurs in diffuse large B-cell lymphoma (DLBCL). We have evaluated the frequency of this translocation in 106 Argentinean non-Hodgkin lymphoma (NHL) patients: 83 with diagnosis of FL and 23 with DLBCL. Nested (N) and long-distance PCR (LD-PCR) approaches were used. By N-PCR, a total of 42 (51%) FL cases showed BCL-2 rearrangement: 28 (34%) for major breakpoint region (MBR) and 14 (17%) for minor cluster region (mcr). By LD-PCR, additional 23 (28%) new positive cases were found: 10 (12%) for MBR and 13 (16%) for mcr. These data make a total of 65 (78%) positive cases for BCL-2 gene rearrangements. In DLBCL cases, N-PCR detected two (9%) cases with the MBR breakpoint and one (4%) with mcr. Seven (30%) new positive cases by LD-PCR were found: four (17%) for MBR and three (13%) for mcr, showing a total of 10 (43%) positive cases. Thus, both FL and DLBCL had high frequencies of breakpoints located between MBR and mcr clusters. Our N-PCR results in FL (51%; 95% CI, 40-62%) showed statistical differences with respect to the pooled data from USA (P < 0.0001) and overlapped with the frequencies from Asia and Europe. In DLBCL, no significant differences with respect to the literature were found. This data support the idea that FL may be a heterogeneous malignancy with distinct molecular pathogenesis and suggest that the geographic differences may be related with the distribution of breakpoints that are widely spread throughout the sequence stretch between MBR and mcr.
Subject(s)
Gene Rearrangement , Genes, bcl-2/genetics , Lymphoma, Non-Hodgkin/genetics , Molecular Epidemiology , Adult , Aged , Aged, 80 and over , Argentina/epidemiology , Chromosome Breakage , Chromosomes, Human, Pair 14 , Chromosomes, Human, Pair 18 , Female , Humans , Incidence , Lymphoma, Follicular/etiology , Lymphoma, Follicular/genetics , Lymphoma, Large B-Cell, Diffuse/genetics , Male , Middle Aged , Polymerase Chain Reaction , Topography, MedicalABSTRACT
We report the clinical, cytogenetic, fluorescence in situ hybridization (FISH) and molecular findings in a 54-yr-old male patient diagnosed with B-cell chronic lymphocytic leukemia (B-CLL), who showed progression to a diffuse large B-cell lymphoma (Richter's syndrome). Genetic studies were performed at diagnosis and during the Richter's transformation (RT). A clonal karyotype with two dicentric chromosomes, psu dic(12,21)(q24;q10) and dic(17,18)(p11.2;p11.2), was found. Both rearrangements were confirmed by FISH. Molecular cytogenetics analysis using p53 probe showed monoallelic loss of this tumor suppressor gene in 43.8% and 77.3% of cells for the first and the second studies, respectively). In both studies, deletions of D13S319 (18% and 12% of cells) and D13S25 loci (13% and 12% of cells) at 13q14 were found. Polymerase chain reaction analysis showed the MBR/JH rearrangement of the bcl-2 gene. FISH studies using LSI bcl-2/IgH probe allowed quantifying the clonal cell population with this rearrangement (4% and 6.6% of cells at diagnosis and RT, respectively). To our knowledge, this is the first case with a psu dic(12,21) described in B-CLL. The low percentage of cells with the 13q14 deletion and bcl-2/IgH rearrangement suggests that they were secondary events that resulted from clonal evolution. Our patient had a short survival (9 months) and a clear lack of response to several therapeutic agents, confirming the association of p53 gene deletion and karyotypic evolution with disease progression.
Subject(s)
Cytogenetic Analysis/methods , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Disease Progression , Gene Deletion , Gene Rearrangement , Genes, p53 , Humans , In Situ Hybridization, Fluorescence , Karyotyping , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Male , Middle Aged , Polymerase Chain ReactionABSTRACT
The translocation t(14;18)(q32;q21) is the most frequent abnormality observed in non-Hodgkin's lymphoma. It determines the juxtaposition of BCL-2/IgH genes. In this study, we have evaluated the frequency and distribution of BCL-2 gene rearrangements in 144 Argentinean patients: 98 with follicular lymphoma (FL) and 46 with diffuse large B-cell lymphoma (DLBCL) (29 de novo and 17 secondary). Nested (N-PCR) and long-distance PCR (LD-PCR) approaches were used. In FL, 53 positive patients (54.1%) were found by N-PCR. By LD-PCR, additional 24 (24.5%) new positive cases were observed, making a total of 77 patients (78.6%) for BCL-2 gene rearrangements. N-PCR approach detected 8 de novo DLBCL positive cases (27.5%) and 9 (52.9%) secondary ones. By LD-PCR, the frequencies increased to 24.1% and 29.4%, respectively, showing total incidences of 51.6% and 82.3%, for each subtype of DLBCL, indicating the presence of different entities. Our N-PCR results in FL showed statistical differences with respect to the data from USA (p < 0.0001) and overlapped with the frequencies from Asia and Europe, suggesting that the geographical differences may be related with the distribution of breakpoints that are widely spread between MBR and mcr clusters. In de novo DLBCL, no significant differences with respect to the literature were found.
La t(14;18)(q32;q21) es la anomalía más frecuente en linfomas no Hodgkin y da origen al rearreglo molecular BCL-2/IgH. En este trabajo evaluamos la frecuencia y distribución de los rearreglos del gen BCL-2 en 144 pacientes argentinos: 98 con linfoma folicular (LF) y 46 con linfoma B difuso a células grandes (LBDCG) (29 de novo y 17 secundarios). Se utilizó PCR anidada (PCR-N) y de larga distancia (PCR-LD). En LF, 53 pacientes (54.1%) fueron positivos por PCR-N, se encontró un incremento del 24% al emplear la técnica de PCR-LD, que dio un total de 77 pacientes positivos (78.6%). En LBDCG, por PCR-N se detectaron 8 (27.5%) casos positivos para los LBDCG de novo y 9 (52.9%) para los secundarios; con incrementos de 24.1% y 29.4% con PCR-LD, con un total de 51.6% y 82.3%, respectivamente, mostrando un comportamiento diferente para ambas entidades. En LF, la comparación de nuestros resultados por PCR-N con los de otras regiones geográficas mostró diferencias significativas respecto de los datos de EE.UU. (p < 0.0001) y superposición con los de Europa y Asia, lo que sugiere que las diferencias geográficas podrían estar relacionadas con la distribución de puntos de ruptura entre MBR y mcr. Los LBDCG de novo no mostraron diferencias con los datos publicados.
Subject(s)
Lymphoma, Non-Hodgkin , Genes, bcl-2 , Incidence , Lymphoma, B-Cell , Lymphoma, Follicular , LymphomaABSTRACT
Los objetivos específicos planteados fueron: Determinar la frecuencia y distribución de los rearreglos de los genes BCL-2 y BCL-6 mediante el análisis molecular por PCR anidada y de larga distancia en nuestra población de pacientes con LF y LBDCG de novo y secundario a un LF. Evaluar la participación de estos rearreglos en el proceso de transformación de los LF a LBDCG. Efectuar la correlación entre los diferentes puntos de ruptura de los genes en evaluación con la evolución clínica de los pacientes, la respuesta al tratamiento y la presencia de enfermedad mínima residual. Comparar nuestros datos con los de las series ya publicadas en la literatura a fin de caracterizar nuestra población acorde a las variaciones geográficas.
Subject(s)
Lymphoma, Non-Hodgkin , Fellowships and ScholarshipsABSTRACT
El linfoma folicular (LF) constituye la forma mas frecuente de los linfomas no-Hodgkin del adulto. El 60-85 por ciento de los casos presenta la t(14;18)(q32;q21), que determina la yuxtaposición del gen BCL-2 con la cadena pesada de las Inmunoglobulinas. El 10-15 por ciento presentan rearreglos en 3q27, donde se ubica el gen BCL-6, dando origen a un subtipo diferente. En el presente proyecto se evaluaron 112 pacientes mediante las técnicas de PCR anidada (A) y PCR de larga distancia (LD), obteniéndose un 53,6 por ciento de individuos portadores de los rearreglos moleculares de gen BCL-2, empleando la técnica de PCR-A y llegando a una frecuencia total del 76,8 por ciento cuando se complementa con la PCR-LD. Se correlacionaron los mismos con diferentes parámetros de interés clínico observándose una asociación entre el punto de ruptura MBR-IgH, edad temprana de presentación de la enfermedad y grado histológico, sugiriendo un mejor pronóstico para estos pacientes. Al evaluar el total de pacientes por PCR-A se observó que 5 de ellos (4,5 por ciento) presentaban doble rearreglo molecular (MBR-JH y mcr-JH), evento muy poco frecuente probablemente asociado a una evolución clonal o a la coexistencia de dos clones diferentes. A fin de cuantificar al clon neoplásico BCL-2/IGH se trabajó en la puesta a punto de la RQ-PCR. Los pacientes sin rearreglo molecular para el gen BCL-2 fueron evaluados para el gen BCL-6 detectando un 9,5 por ciento de casos positivos, similar a la frecuencia reportada en la literatura (10-15 por ciento). La realización del presente estudio ha permitido una mejor caracterización de los pacientes con LF, indicando la importancia de este tipo de análisis en neoplasias linfoides.
Subject(s)
Lymphoma, Follicular , Fellowships and ScholarshipsABSTRACT
El linfoma folicular (LF) constituye la forma mas frecuente de los linfomas no-Hodgkin del adulto. El 60-85 por ciento de los casos presenta la t(14;18)(q32;q21), que determina la yuxtaposición del gen BCL-2 con la cadena pesada de las Inmunoglobulinas. El 10-15 por ciento presentan rearreglos en 3q27, donde se ubica el gen BCL-6, dando origen a un subtipo diferente. En el presente proyecto se evaluaron 112 pacientes mediante las técnicas de PCR anidada (A) y PCR de larga distancia (LD), obteniéndose un 53,6 por ciento de individuos portadores de los rearreglos moleculares de gen BCL-2, empleando la técnica de PCR-A y llegando a una frecuencia total del 76,8 por ciento cuando se complementa con la PCR-LD. Se correlacionaron los mismos con diferentes parámetros de interés clínico observándose una asociación entre el punto de ruptura MBR-IgH, edad temprana de presentación de la enfermedad y grado histológico, sugiriendo un mejor pronóstico para estos pacientes. Al evaluar el total de pacientes por PCR-A se observó que 5 de ellos (4,5 por ciento) presentaban doble rearreglo molecular (MBR-JH y mcr-JH), evento muy poco frecuente probablemente asociado a una evolución clonal o a la coexistencia de dos clones diferentes. A fin de cuantificar al clon neoplásico BCL-2/IGH se trabajó en la puesta a punto de la RQ-PCR. Los pacientes sin rearreglo molecular para el gen BCL-2 fueron evaluados para el gen BCL-6 detectando un 9,5 por ciento de casos positivos, similar a la frecuencia reportada en la literatura (10-15 por ciento). La realización del presente estudio ha permitido una mejor caracterización de los pacientes con LF, indicando la importancia de este tipo de análisis en neoplasias linfoides.
Subject(s)
Lymphoma, Follicular , Fellowships and ScholarshipsABSTRACT
Los objetivos específicos planteados fueron: Determinar la frecuencia y distribución de los rearreglos de los genes BCL-2 y BCL-6 mediante el análisis molecular por PCR anidada y de larga distancia en nuestra población de pacientes con LF y LBDCG de novo y secundario a un LF. Evaluar la participación de estos rearreglos en el proceso de transformación de los LF a LBDCG. Efectuar la correlación entre los diferentes puntos de ruptura de los genes en evaluación con la evolución clínica de los pacientes, la respuesta al tratamiento y la presencia de enfermedad mínima residual. Comparar nuestros datos con los de las series ya publicadas en la literatura a fin de caracterizar nuestra población acorde a las variaciones geográficas.
Subject(s)
Genes, bcl-2 , Lymphoma, Non-Hodgkin , Fellowships and ScholarshipsABSTRACT
El linfoma folicular (LF) constituye la forma mas frecuente de los linfomas no-Hodgkin del adulto. El 60-85 por ciento de los casos presenta la t(14;18)(q32;q21), que determina la yuxtaposición del gen BCL-2 con la cadena pesada de las Inmunoglobulinas. El 10-15 por ciento presentan rearreglos en 3q27, donde se ubica el gen BCL-6, dando origen a un subtipo diferente. En el presente proyecto se evaluaron 112 pacientes mediante las técnicas de PCR anidada (A) y PCR de larga distancia (LD), obteniéndose un 53,6 por ciento de individuos portadores de los rearreglos moleculares de gen BCL-2, empleando la técnica de PCR-A y llegando a una frecuencia total del 76,8 por ciento cuando se complementa con la PCR-LD. Se correlacionaron los mismos con diferentes parámetros de interés clínico observándose una asociación entre el punto de ruptura MBR-IgH, edad temprana de presentación de la enfermedad y grado histológico, sugiriendo un mejor pronóstico para estos pacientes. Al evaluar el total de pacientes por PCR-A se observó que 5 de ellos (4,5 por ciento) presentaban doble rearreglo molecular (MBR-JH y mcr-JH), evento muy poco frecuente probablemente asociado a una evolución clonal o a la coexistencia de dos clones diferentes. A fin de cuantificar al clon neoplásico BCL-2/IGH se trabajó en la puesta a punto de la RQ-PCR. Los pacientes sin rearreglo molecular para el gen BCL-2 fueron evaluados para el gen BCL-6 detectando un 9,5 por ciento de casos positivos, similar a la frecuencia reportada en la literatura (10-15 por ciento). La realización del presente estudio ha permitido una mejor caracterización de los pacientes con LF, indicando la importancia de este tipo de análisis en neoplasias linfoides.
Subject(s)
Lymphoma, Follicular , Fellowships and ScholarshipsABSTRACT
Los objetivos específicos planteados fueron: Determinar la frecuencia y distribución de los rearreglos de los genes BCL-2 y BCL-6 mediante el análisis molecular por PCR anidada y de larga distancia en nuestra población de pacientes con LF y LBDCG de novo y secundario a un LF. Evaluar la participación de estos rearreglos en el proceso de transformación de los LF a LBDCG. Efectuar la correlación entre los diferentes puntos de ruptura de los genes en evaluación con la evolución clínica de los pacientes, la respuesta al tratamiento y la presencia de enfermedad mínima residual. Comparar nuestros datos con los de las series ya publicadas en la literatura a fin de caracterizar nuestra población acorde a las variaciones geográficas.