ABSTRACT
TP53 gene disruption, including 17p13 deletion [del(17p)] and/or TP53 mutations, is a negative prognostic biomarker in chronic lymphocytic leukemia (CLL) associated with disease progression, treatment failure and shorter survival. Germline variants in p53 signaling pathway genes could also lead to p53 dysfunction, but their involvement in CLL has not been thoroughly evaluated. The aim of this study was to determine the association of TP53, MDM2 and NQO1 gene variability with clinical and genetic data of CLL patients. Individual genotype and haplotype data of CLL patients were compared with clinical prognostic factors, cytogenetic and molecular cytogenetic findings as well as IGHV and TP53 mutational status. The study included 116 CLL patients and 161 healthy blood donors. TP53 (rs1042522, rs59758982, rs1625895), NQO1 (rs1800566) and MDM2 (rs2279744, rs150550023) variants were genotyped using different PCR approaches. Analysis of genotype frequencies revealed no association with the risk of CLL. TP53 rs1042522, rs1625895 and MDM2 rs2279744 variants were significantly associated with abnormal karyotype and the presence of del(17p). Similarly, these two TP53 variants were associated with TP53 disruption. Moreover, TP53 C-A-nondel and G-A-del haplotypes (rs1042522-rs1625895-rs59758982) were associated with an increased likelihood of carrying del(17p) and TP53 disruptions. MDM2 T-nondel haplotype (rs2279744-rs150550023) was found to be a low risk factor for del(17p) (OR = 0.32; CI: 0.12-0.82; p = 0.02) and TP53 disruptions (OR = 0.41; CI: 0.18-0.95; p = 0.04). Our findings suggest that TP53 and MDM2 variants may modulate the risk to have chromosome alterations and TP53 disruptions, particularly del(17p). To our knowledge this is the first study of several germline variants in p53 pathway genes in Argentine patients with CLL.
ABSTRACT
Cytogenetic abnormalities (CA) such as t(4;14), t(14;16), and del(17p), are associated with a poor prognosis in Multiple Myeloma (MM) patients. However, there is scarce information regarding the Latin-American population. This study aims to analyze the impact of t(4;14), t(14;16), and del(17p) on the progression-free survival (PFS) and overall survival (OS) of transplant-eligible newly-diagnosed MM (NDMM) patients in Latin America. Retrospective survival analysis based on the Grupo de Estudio Latinoamericano de MM (GELAMM) registry, including all adult patients with NDMM harboring CA t(4;14), t(14;16), and/or del(17p). Fifty-nine patients were included; the median age was 57 years, 55.9% males, 22% ISS-I, 25.4% ISS-II, and 47.5% ISS-III. The majority (89.8%) had one alteration, whereas 10.2% had del(17p) and t(4;14). The frequencies of CA were del(17p) in 61.0%, t(4;14) in 25.4%, and t(14;16) in 3,4%. Autologous stem cell transplantation was performed in 36 cases, 20 patients did not use this consolidative strategy, and this data was missed in three cases. Five-year OS for the entire cohort was 60.8% and 5-year PFS was 28.1%. Bortezomib-based induction regimen (BBR) (p=0.029), consolidation with ASCT (p<0.001), and maintenance therapy (p=0.004) were associated with an improved 5-year OS. In the multivariate analysis, ASCT was the only variable with a positive impact on OS (HR 0.11, 95% CI 0.033 to 0.34, p<0.001). The median PFS presented a non-statistically significant benefit in BBR, ASCT, and maintenance therapy groups. BBR induction, ASCT, and maintenance therapy were associated with improved OS in high-risk NDMM patients.
Subject(s)
Hematopoietic Stem Cell Transplantation , Multiple Myeloma , Male , Adult , Humans , Middle Aged , Female , Multiple Myeloma/diagnosis , Multiple Myeloma/genetics , Multiple Myeloma/therapy , Prognosis , Retrospective Studies , Transplantation, Autologous , Survival Analysis , Chromosome Aberrations , Antineoplastic Combined Chemotherapy Protocols/therapeutic useABSTRACT
Chronic lymphocytic leukemia (CLL) is the most common mature B-cell neoplasm in the West. IGHV4-34 is one of the most frequently used genes in CLL patients, which usually display an indolent outcome. In this study, we explored the mutational profile of CLL patients expressing IGHV4-34 within different stereotypes and their association with prognostic factors and clinical outcome. A multi-institutional cohort of unselected 1444 CLL patients was analyzed by RT-PCR and bidirectional sequencing. Cytogenetics and molecular cytogenetics analyses were also performed. We identified 144 (10%) IGHV4-34 expressing cases, 119 mutated (M), 44 of them with stereotyped B-cell receptors. Subset #4 was the most frequent (56.8% of cases) followed by subsets #16 (13.6%), #29 (6.8%), and #201 (2.3%), with different distribution among countries. Analysis of somatic hypermutation profile showed significant differences among stereotyped subsets for G28>D/E, P45>S, E55>Q, and S64>I changes (p < 0.01) and high frequency of disruption of the glycosylation motif in the VH CDR2 region. All stereotyped IGHV4-34 cases showed normal karyotypes. Deletion 13q14 as a sole alteration was present in 42.8% of stereotyped cases with a different distribution among subsets. A shorter time to first treatment was found in non-stereotyped vs. stereotyped M-IGHV4-34 patients (p = 0.034). Our results add new information supporting the importance of recurrent amino acid changes at particular positions, contributing to refine the molecular characterization of South American CLL patients.
Subject(s)
Immunoglobulin Heavy Chains/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Aged , Cohort Studies , Female , Gene Rearrangement , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/epidemiology , Male , Middle Aged , Mutation , Receptors, Antigen, B-Cell/genetics , Somatic Hypermutation, Immunoglobulin , South America/epidemiologyABSTRACT
El mieloma múltiple (MM) es una neoplasia de células B post-centro germinal, asociada a alta heterogeneidad en su evolución clínica. Los estudios genéticos constituyen herramientas de gran utilidad en su estudio, tanto al momento del diagnóstico y la recaída, así como en las decisiones terapéuticas. El objetivo general del presente plan es el estudio de marcadores genéticos asociados a pacientes con MM de comportamiento agresivo, tendiente a comprender su participación en el proceso de progresión de la enfermedad y resistencia al tratamiento, siendo sus objetivos específicos. Efectuar la caracterización citogenética, citomolecular y molecular de rearreglos genómicos en pacientes con MM; -Analizar alteraciones genéticas que permitan refinar la detección de subgruposde alto riesgo, contribuyendo a una adecuada valoración pronóstica; -Correlacionar los datos genómicos con los parámetros clínicos, contribuyendo a una mayor comprensión de los mecanismos genéticos implicados en la progresión de la enfermedad y resistencia al tratamiento. Se emplearon muestras de médula ósea de pacientes con diagnóstico de MM. Las muestras se procesaron utilizando técnicas citogenéticas, citomoleculares y moleculares. Se evaluaron 27 pacientes nuevos mediante citogenética y FISH, detectándose alteraciones cromosómicas en el 63% de los casos; tres pacientes presentaron deleción y mutación del gen TP53. Asimismo, se analizó retrospectivamente la presencia de alteraciones del cromosoma 1 en una cohorte de 111 pacientes del Laboratorio, observándose dichas anomalías en el 27% de los casos, asociadas a mal pronóstico y se analizó la distribución de alteraciones en pacientes mayores y menores de 65 años, detectándose mayor frecuencia de cariotipos hipodiploides en los <65 años (46%) respecto de los >65 años (29%) (p<0.016), indicando lamimportancia de estos estudios para refinar los grupos de riesgo citogenético en MM.
Subject(s)
Cytogenetics , Multiple MyelomaABSTRACT
Burkitt lymphoma/leukemia (BL/L) is an aggressive mature B-cell malignancy cytogenetically characterized by the translocation t(8;14)(q24;q32) or its variants, which determines the juxtaposition of the MYC oncogene to one of the three immunoglobulin loci. In addition to MYC translocations, different secondary genetic abnormalities have been described, some of them with prognostic significance. However, dual translocations of chromosome 14, except those involving chromosome 18, are very rare events in this pathology. Herein, we present the coexistence of translocations t(8;14) and t(14;15) in a pediatric BL/L patient. To our knowledge, this is the first report of a translocation t(14;15)(q32;q22) as a secondary alteration in a BL/L patient. The patient had multiple complications at diagnosis but he evolved favorably reaching complete remission. The description of new secondary alterations in this pathology as well as their impact on clinical evolution, add information to the biological characterization of BL, contributing to a higher accuracy in the diagnosis and/or prognosis of the disease.
Subject(s)
Burkitt Lymphoma/pathology , Chromosomes, Human, Pair 14/genetics , Chromosomes, Human, Pair 8/genetics , Translocation, Genetic , Burkitt Lymphoma/genetics , Child , Humans , Male , PrognosisABSTRACT
Resumen Introducción: El linfoma de Hodgkin clásico presenta escasas células de Reed Sternberg/Hodgkin inmersas en un abundante microambiente tumoral. Los desbalances genómicos del locus 9p24.1 han sido asociados con alteraciones en la expresión de los genes del ligando de muerte celular 1 y 2, ambos reguladores de la respuesta inmune. Objetivo: Evaluar desbalances genómicos del locus 9p24.1 en células de Reed Sternberg/Hodgkin y del microambiente tumoral en biopsias de pacientes con linfoma de Hodgkin clásico y correlacionarlo con la expresión del ligando de muerte celular 1 y la presentación de la enfermedad. Materiales y Métodos: Se efectuó hibridación in situ en biopsias de 22 pacientes con linfoma de Hodgkin clásico dirigida a los genes del ligando de muerte celular 1 y 2. Las alteraciones se clasificaron en: amplificación, ganancia y polisomía. La expresión se evaluó mediante inmunohistoquímica. Resultados: Todos los pacientes mostraron alteraciones del número de copias. Se diferenciaron dos grupos: con amplificación (32%) y sin amplificación (68%); este último subdividido en: rico en ganancia (53%) y rico en polisomías (47%). El grupo rico en polisomías mostró mayor edad (p=0,027). El 40% de los pacientes con amplificación y rico en ganancias no presentó masa bulky. La expresión proteica mostró score +3 sólo en estos últimos. El title% de los casos ricos en polisomías presentaron monosomía del cromosoma 9 en los linfocitos circundantes respecto al 36,4% de los otros dos grupos. Conclusiones: Nuestros datos constituyen un aporte a la caracterización biológica del LHC, de interés en el marco de las nuevas modalidades terapéuticas. MÉD.UIS.2020;34(1):35-44.
Abstract Background: Classical Hodgkin lymphoma shows scarce tumor Reed-Sternberg/Hodgkin cells surrounded by a dense immune microenvironment. Genetic alterations at the 9p24.1 locus result in genomic imbalances in the copy number of PD-L1/PD-L2 genes, both of them being immune response regulators. Aim: To characterize genomic imbalances at the 9p24.1 locus in Reed-Sternberg/Hodgkin cells and immune microenvironment in biopsies of patients with Classical Hodgkin lymphoma and correlate it with PD-L1 protein expression and disease presentation. Material and Methods: Paraffin embedded biopsies of 22 patients with CHL were retrospectively evaluated by fluorescence in situ hybridization using SPEC CD274/PDCD1LG2/CEN9 DNA probe. The frequency of 9p24.1 alterations, amplification, copy gain and polysomy, were determined taking into account the number of gene copies with respect to the centromere. PD-L1 protein expression was evaluated by immunohistochemistry. Results: All cases presented alterations in the number of copies of PD-L1 / PD-L2, which are differentiated in two groups: with amplification (32%) and without amplification (68%). The latter was subdivided into rich in gains (RG) (53%) and rich in polysomies (RP) (47%). Groups with amplification and RG were younger than the RP group (p = 0.027). The latter was not associated with bulky disease, a fact observed in 40% of patients with amplification and RG. Protein expression showed score +3 only in the latter. All RP cases presented chromosome 9 monosomy in the surrounding lymphocytes, compared to 36.4% of the other two groups. Conclusions: Our data contributes to the biologic characterization of CHL, of interest in the context of new therapeutic modalities. MÉD.UIS.2020;34(1):35-44
Subject(s)
Humans , Hodgkin Disease , Gene Expression , In Situ Hybridization, FluorescenceABSTRACT
Chronic lymphocytic leukemia (CLL) is the most common type of adult leukemia in the western hemisphere. It is characterized by a clonal proliferation of a population of CD5+ B lymphocytes that accumulate in the secondary lymphoid tissues, bone marrow, and blood. Some CLL patients remain free of symptoms for decades, whereas others rapidly become symptomatic or develop high-risk disease. Studying autophagy, which may modulate key protein expression and cell survival, may be important to the search for novel prognostic factors and molecules. Here, we applied flow cytometry technology to simultaneously detect autophagy protein LC3B with classical phenotypical markers used for the identification of tumoral CLL B cell clones. We found that two patients with progressing CLL showed increased expression of the autophagy protein LC3B, in addition to positive expression of CD38 and ZAP70 and unmutated status of IGHV. Our data suggest that activation of autophagy flux may correlate with CLL progression even before Ibrutinib treatment.
Subject(s)
Autophagy , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Microtubule-Associated Proteins/metabolism , Mutation , Adult , Disease Progression , Female , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Male , Middle Aged , PrognosisSubject(s)
Ethnicity/genetics , Immunoglobulin Variable Region/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Receptors, Antigen, B-Cell/genetics , Biomarkers, Tumor , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/epidemiology , Leukemia, Lymphocytic, Chronic, B-Cell/ethnology , Mutation , South America/epidemiologyABSTRACT
Genomic instability is a hallmark of cancer, contributing to tumour development and transformation, being chromosome instability (CIN) the most common form in human cancer. Chronic lymphocytic leukaemia (CLL) is the most frequent adult leukaemia in the Western world. In this study, we have evaluated basal CIN in untreated patients with CLL by measuring chromosome aberrations (CAs) and micronucleus (MN) frequency and their association with different prognostic factors. Seventy-two patients and 21 normal controls were analysed. Cytogenetic and fluorescence in situ hybridisation (FISH) studies were performed. IGHV (immunoglobulin heavy chain variable region) mutational status was evaluated by reverse transcription polymerase chain reaction and sequencing. An increased number of CA in patients compared with controls (P = 0.0001) was observed. Cases with abnormal karyotypes showed increased CA rate than those with normal karyotypes (P = 0.0026), with a particularly highest frequency in cases with complex karyotypes. Among FISH risk groups, a significant low frequency of CA was found in patients with no FISH alterations compared to those with del13q14 and ≥2 FISH alterations (P = 0.0074). When mean CA value (6.7%) was considered, significant differences in the distribution of low and high CA frequency between cases with normal and abnormal karyotypes (P = 0.002) were observed. By MN analysis, higher frequency in patients compared to controls (P = 0.0001) was also found, as well as between cases with ≥2 FISH abnormalities and those with no FISH alterations (P = 0.026). Similarly, significant differences were observed when patients were divided according to mean MN frequency (2.2%; P ≤ 0.04). Interestingly, patients with high MN frequency had shorter time to first treatment than those with low frequency (P = 0.024). Cases with mutated and unmutated IGHV status showed increased CA and MN frequencies compared to controls (P ≤ 0.0007), but no differences between both groups were found. Our results support the strong interaction between CIN and genomic complexity as well as their influence on poor outcome in this pathology.
Subject(s)
Chromosomal Instability , Chromosome Aberrations , Genetic Predisposition to Disease , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Adult , Aged , Aged, 80 and over , Biomarkers, Tumor , Carcinoma in Situ , Female , Genetic Association Studies , Genomic Instability , Humans , Immunoglobulin Variable Region , In Situ Hybridization, Fluorescence , Karyotyping , Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis , Male , Middle Aged , MutationABSTRACT
Chronic lymphocytic leukemia (CLL) is the most common leukemia in the Western world. The disease has\r\na highly variable clinical course, ranging from very indolent cases to patients with aggressive and rapidly\r\nprogressing outcome. Genetic studies are useful tools in analyzing this pathology, and have been incorporated in international risk classifications. The analysis of genomic rearrangements and the mutational status of immunoglobulin heavy chain variable have allowed risk groups of high prognostic value to be established. More recently, next generation sequencing studies have identified novel somatic mutations that could explain the wide clinical variability of this pathology. Among them, the analysis of NOTCH1 (neurogenic locus notch homolog protein 1) gene mutations are of interest, as deregulation is associated with tumorigenesis. NOTCH11 mutations are mostly located at exon 34 (80% of cases) and 3´UTR (untranslated region). They produce premature stop codons that produce a constitutively active and stable NOTCH1 protein. NOTCH1 mutations are associated with adverse prognosis and refractoriness to treatment. The aim of this study was to analyze NOTCH1 mutations in CLL patients by ASO-PCR and sequencing. Our results found 4.4% of cases with NOTCH1 mutated values concordant with international observations (5%-10%). Including them in the genetic status of CLL patients allows the characterization of risk groups, an aspect of great importance in clinical practice and therapeutic decisions, to be refined.
La leucemia linfocítica crónica (LLC) es la leucemia más frecuente en adultos de Occidente. Presenta\r\nun curso clínico altamente variable, con pacientes que requieren tratamiento inmediato y otros con un curso indolente de la enfermedad. Los estudios genéticos constituyen herramientas de suma utilidad en esta enfermedad, encontrándose incorporados a las clasificaciones de riesgo internacionales. El análisis de los rearreglos genómicos y del estado mutacional de los genes IGHV (immunoglobulin heavy chain variable region) ha hecho factible establecer grupos de riesgo de alto valor pronóstico. Más recientemente, estudios de secuenciación de última generación permitieron la detección de mutaciones\r\nsomáticas previamente desconocidas en esta afección, que podrían explicar la amplia variabilidad clínica\r\nobservada en la LLC. Entre ellas, resultan de interés las observadas en el gen NOTCH1 (neurogenic locus notch homolog protein 1), cuya desregulación se asocia con el desarrollo tumoral. Estas mutaciones se acumulan en mayor medida en el exón 34 (80% de los casos) y en la región 3´UTR (untraslated region), lo que genera codones de terminación prematuros que originan una proteína NOTCH1 constitutivamente activa y más estable, los cuales se asocian con pronóstico adverso y refractariedad al tratamiento. Nuestro objetivo fue evaluar mutaciones de NOTCH1 en nuestros pacientes mediante ASO-PCR y secuenciación. Se detectaron mutaciones en el 4.4% de los casos, valor concordante con los datos internacionales (5% a 10%). Su inclusión en la caracterización genética de los pacientes con LLC permitirá refinar la categorización de los grupos de riesgo, aspecto de suma importancia tanto en el seguimiento clínico como en la toma de decisiones terapéuticas.
Subject(s)
Humans , Leukemia, Lymphocytic, Chronic, B-Cell , Cytogenetics , Receptor, Notch1 , Mutation/geneticsSubject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Biomarkers , Biomarkers, Tumor , Disease Susceptibility , Female , Flow Cytometry , Gene Expression , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis , Leukemia, Lymphocytic, Chronic, B-Cell/etiology , Leukemia, Lymphocytic, Chronic, B-Cell/mortality , Male , Mutation , Sirolimus/administration & dosage , Treatment Outcome , Vidarabine/administration & dosage , Vidarabine/analogs & derivativesSubject(s)
Gene Rearrangement , Immunoglobulin Heavy Chains/genetics , Immunoglobulin Variable Region/genetics , Inclusion Bodies/pathology , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Mutation , Aged , Female , Humans , Inclusion Bodies/metabolism , PrognosisABSTRACT
Telomeres are protective repeats of TTAGGG sequences located at the end of human chromosomes. They are essential to maintain chromosomal integrity and genome stability. Telomerase is a ribonucleoprotein complex containing an internal RNA template (hTR) and a catalytic subunit (hTERT). The human hTR gene consists of three major domains; among them the H/ACA domain is essential for telomere biogenesis. H/ACA ribonucleoprotein (RNP) complex is composed of four evolutionary conserved proteins, including dyskerin (encoded by DKC1 gene), NOP10, NHP2 and GAR1. In this study, we have evaluated the expression profile of the H/ACA RNP complex genes: DKC1, NOP10, NHP2 and GAR1, as well as hTERT and hTR mRNA levels, in patients with chronic lymphocytic leukemia (CLL). Results were correlated with the number and type of genetic alteration detected by conventional cytogenetics and FISH (fluorescence in situ hybridization), IGHV (immunoglobulin heavy chain variable region) mutational status, telomere length (TL) and clinico-pathological characteristics of patients. Our results showed significant decreased expression of GAR1, NOP10, DKC1 and hTR, as well as increased mRNA levels of hTERT in patients compared to controls (p≤0.04). A positive correlation between the expression of GAR1-NHP2, GAR1-NOP10, and NOP10-NHP2 (p<0.0001), were observed. The analysis taking into account prognostic factors showed a significant increased expression of hTERT gene in unmutated-IGHV cases compared to mutated-CLL patients (p = 0.0185). The comparisons among FISH groups exhibited increased expression of DKC1 in cases with two or more alterations with respect to no abnormalities, trisomy 12 and del13q14, and of NHP2 and NOP10 compared to those with del13q14 (p = 0.03). The analysis according to TL showed a significant increased expression of hTERT (p = 0.0074) and DKC1 (p = 0.0036) in patients with short telomeres compared to those with long TL. No association between gene expression and clinical parameters was found. Our results suggest a role for these telomere associated genes in genomic instability and telomere dysfunction in CLL.
Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Ribonucleoproteins/metabolism , Adult , Aged , Aged, 80 and over , Female , Gene Expression Profiling , Humans , In Situ Hybridization, Fluorescence , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Male , Middle Aged , Prognosis , Real-Time Polymerase Chain Reaction , TelomereABSTRACT
INTRODUCTION: Obesity is the principal component in the Metabolic Syndrome (MetS) that determines the progression of metabolic complications. Metabolically healthy obese (MHO) individuals seem to be protected against those complications. Telomere length (TL) as a novel marker of cellular aging had a complex relationship to the MetS. The principal aim of this study was to investigate the TL in MHO, and to study the association between TL and the worsening of the metabolic condition. MATERIAL AND METHODS: We have determined the absolute TL (aTL) in 400 women (mean age of 46.76 ± 15.47 years; range: 18-86 years), grouped according to the metabolic condition in three groups: metabolically healthy non-obese women (MHNO), MHO and obese women with MetS (MSO); and grouped according to the number of components of MetS. RESULTS: We found that MHO displays significantly higher aTL than MSO (p = 0.033; r = -4.63; 95% CI r = -8.89 / -0.37), but did not differ from MHNO. A decrease in aTL with the progressive increase in the number of MetS components was also observed (p < 0.001; r = -2.06; 95% CI r = -3.13 / -0.99). In this way, our results indicate that aTL is influenced by the presence of MetS, but it is not affected by the presence of obesity. DISCUSSION: We found that shorter aTL is not associated with MHO, but is related to MetS and with the increased number of metabolic abnormalities.
Subject(s)
Metabolic Syndrome/genetics , Obesity, Metabolically Benign/genetics , Telomere , Adolescent , Adult , Aged , Aged, 80 and over , Humans , Middle Aged , Young AdultSubject(s)
Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Phosphotransferases (Alcohol Group Acceptor)/genetics , Biomarkers , Cell Proliferation/genetics , Cell Survival/genetics , Disease Progression , Female , Humans , Immunophenotyping , Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Male , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Signal TransductionABSTRACT
BACKGROUND: Glutathione S-transferases (GSTs) are drug-metabolising enzymes involved in biotransformation of carcinogens, drugs, xenobiotics and oxygen free radicals. Polymorphisms of GST genes contribute to inter-individual and population variability in the susceptibility to environmental risk factors, cancer predisposition and pharmacotherapy responses. However, data about GST variability in Argentina are lacking. AIM: The purpose was to determine the prevalence of GSTM1, GSTT1 and GSTP1 polymorphisms in the general population from a central region of Argentina and to perform inter-population comparisons. SUBJECTS AND METHODS: GSTM1 and GSTT1 gene deletions and GSTP1 c.313A > G were genotyped by PCR assays in 609 healthy and unrelated Argentinians. RESULTS: The frequencies of variant genotypes in Argentinians were GSTM1-null (45%), GSTT1-null (17%) and GSTP1-GG (11%). GSTM1-present genotype was significantly associated with GSTP1-AG or GSTP1-GG variants (p = 0.037; p = 0.034, respectively). Comparison with worldwide populations demonstrated that the GST distributions in Argentina are similar to those reported for Italy and Spain, whereas significant differences were observed regarding Asian and African populations (p < 0.001). CONCLUSION: This study has determined, for the first time, the normative profile of three pharmacogenetically relevant polymorphisms (GSTM1, GSTT1 and GSTP1) in the largest Argentinian cohort described to date, providing the basis for further epidemiological and pharmacogenetic studies in this country.
Subject(s)
Glutathione S-Transferase pi/genetics , Glutathione Transferase/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Argentina , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Polymorphism, Genetic , Young AdultABSTRACT
Telomeres are highly regulated and dynamic complexes that protect the genomic DNA and prevent the end of linear chromosomes from being misrecognized as a broken DNA. Due to the end replication problem, telomeres of somatic cells shorten with each cell division, inducing cell senescence. Telomerase is a reverse transcriptase capable of compensating telomere attrition by adding telomere repeats to the ends of chromosomes. Human telomeres are associated with the shelterin complex which consists of six telomere-associated proteins that specifically bind to telomeric DNA. Alterations or removal of individual shelterin components would lead to telomere uncapping and telomere dysfunction, resulting in cellular senescence and transformation to a malignant state. Another complex of multifunctional proteins, named non-shelterin complex, is thought to prevent telomere degradation and facilitate telomerase-based telomere elongation. As telomerase is highly expressed in most human tumor cells, it is considered an attractive target for new therapeutic strategies. In this review, we will summarize the characteristics of telomeres and telomerase in lymphoid malignancies and discuss the role of telomere-associated proteins in these entities.
Subject(s)
Hematologic Neoplasms/genetics , Hematologic Neoplasms/metabolism , Telomere/genetics , Telomere/metabolism , Animals , Cellular Senescence/genetics , Hematologic Neoplasms/pathology , Humans , Telomerase/genetics , Telomerase/metabolismABSTRACT
Small molecules targeting kinases involved in B cell receptor signaling are showing encouraging clinical activity in chronic lymphocytic leukemia (CLL) patients. Fostamatinib (R406) and entospletinib (GS-9973) are ATP-competitive inhibitors designed to target spleen tyrosine kinase (Syk) that have shown clinical activity with acceptable toxicity in trials with CLL patients. Preclinical studies with these inhibitors in CLL have focused on their effect in patient-derived leukemic B cells. In this work we show that clinically relevant doses of R406 and GS-9973 impaired the activation and proliferation of T cells from CLL patients. This effect could not be ascribed to Syk-inhibition given that we show that T cells from CLL patients do not express Syk protein. Interestingly, ζ-chain-associated protein kinase (ZAP)-70 phosphorylation was diminished by both inhibitors upon TCR stimulation on T cells. In addition, we found that both agents reduced macrophage-mediated phagocytosis of rituximab-coated CLL cells. Overall, these results suggest that in CLL patients treated with R406 or GS-9973 T cell functions, as well as macrophage-mediated anti-tumor activity of rituximab, might be impaired. The potential consequences for CLL-treated patients are discussed.
Subject(s)
Indazoles/pharmacology , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Macrophages/immunology , Oxazines/pharmacology , Pyrazines/pharmacology , Pyridines/pharmacology , Syk Kinase/antagonists & inhibitors , T-Lymphocytes/drug effects , ZAP-70 Protein-Tyrosine Kinase/metabolism , Aged , Aged, 80 and over , Cell Proliferation/drug effects , Cells, Cultured , Female , Humans , Lymphocyte Activation/drug effects , Male , Middle Aged , Phagocytosis/drug effects , Phosphorylation/drug effects , Receptors, Antigen, T-Cell/immunology , Receptors, Antigen, T-Cell/metabolism , Rituximab/pharmacology , T-Lymphocytes/immunologyABSTRACT
Mycosis fungoides is the most common type of primary cutaneous T cell lymphoma. We have evaluated CDKN2A losses and MYC gains/amplifications by FISH analysis, as well as expression of miR-155 and members of the oncogenic cluster miR-17-92 (miR17, miR18a, miR19b, and miR92a) in MF patients with advanced disease. Formalin-fixed paraffin-embedded skin biopsies from 36 patients at diagnosis, 16 with tumoral MF (T-MF), 13 in histological transformation to a large T cell lymphoma (TR-MF), and 7 cases with folliculotropic variant (F-MF), were studied. Twenty cases showed genomic alterations (GAs): 8 (40 %) had CDKN2A deletion, 7 (35 %) showed MYC gain, and 5 (25 %) exhibited both alterations. GAs were more frequently observed in F-MF (p = 0.004) and TR-MF (p = 0.0001) than T-MF. GAs were significantly higher in cases presenting lesions in head, neck, and lower extremities compared to those observed in trunk and upper extremities (p = 0.03), when ≥25 % neoplastic cells were CD30 positive (p = 0.016) as well as in cases with higher Ki-67 proliferation index (p = 0.003). Patients with GAs showed bad response to treatment (p = 0.02) and short survival (p = 0.04). Furthermore, MF patients showed higher miRNA expression compared to controls (p ≤ 0.0223). T-MF showed higher miR17 and miR-18a expression compared to F-MF and TR-MF (p ≤ 0.0387) while miR19b, miR92a, and miR-155 showed increased levels in F-MF and TR-MF with respect to T-MF (p ≤ 0.0360). Increased expression of miR17 and miR19b in GA group compared to cases without alterations (p ≥ 0.0307) was also detected. Our results add new information about genomic imbalances in MF patients, particularly in F-MF, and extend the present view of miRNA deregulation in this disease.
Subject(s)
Biomarkers, Tumor/genetics , Genomic Instability , Lymphoma, T-Cell, Cutaneous/genetics , MicroRNAs/genetics , Mycosis Fungoides/genetics , Skin Neoplasms/genetics , Transcriptome , Adult , Aged , Aged, 80 and over , Chromosomes, Human, Pair 8/genetics , Chromosomes, Human, Pair 9/genetics , Female , Follow-Up Studies , Genomics/methods , Humans , In Situ Hybridization, Fluorescence , Lymphoma, T-Cell, Cutaneous/pathology , Male , Middle Aged , Mycosis Fungoides/pathology , Neoplasm Staging , Prognosis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Skin Neoplasms/pathologyABSTRACT
Mantle cell lymphoma (MCL) is a heterogeneous B-cell lymphoid malignancy where most patients follow an aggressive clinical course whereas others are associated with an indolent performance. SOX4, SOX11, and SOX12 belong to SOXC family of transcription factors involved in embryonic neurogenesis and tissue remodeling. Among them, SOX11 has been found aberrantly expressed in most aggressive MCL patients, being considered a reliable biomarker in the pathology. Several studies have revealed that microRNAs (miRs) from the miR-17-92 cluster are among the most deregulated miRNAs in human cancers, still little is known about this cluster in MCL. In this study we screened the transcriptional profiles of 70 MCL patients for SOXC cluster and miR17, miR18a, miR19b and miR92a, from the miR-17-92 cluster. Gene expression analysis showed higher SOX11 and SOX12 levels compared to SOX4 (P ≤ 0.0026). Moreover we found a negative correlation between the expression of SOX11 and SOX4 (P < 0.0001). miR17-92 cluster analysis showed that miR19b and miR92a exhibited higher levels than miR17 and miR18a (P < 0.0001). Unsupervised hierarchical clustering revealed two subgroups with significant differences in relation to aggressive MCL features, such as blastoid morphological variant (P = 0.0412), nodal presentation (P = 0.0492), CD5(+) (P = 0.0004) and shorter overall survival (P < 0.0001). Together, our findings show for the first time an association between the differential expression profiles of SOXC and miR17-92 clusters in MCL and also relate them to different clinical subtypes of the disease adding new biological information that may contribute to a better understanding of this pathology. © 2016 Wiley Periodicals, Inc.