Project description:Genomic analysis of DLBCL, FL and CLL. Genomic DNA from tumor samples analysed using Affymetrix 250K Sty Single Nucleotide Polymorphism microarrays.
Project description:Richter syndrome (RS) occurs in up to 15% of patients with chronic lymphocytic leukemia (CLL). While RS, usually represented by the histologic transformation to a diffuse large B-cell lymphoma (DLBCL), is associated with a very poor outcome, especially when clonally related to the pre-existing CLL, mechanisms leading to RS have not been clarified yet. To better understand the pathogenesis of RS, we analyzed a series of cases including: 59 RS, 28 CLL-phase of RS, 315 CLL and 127 de novo DLBCL. RS demonstrated a genomic complexity intermediate between CLL and DLBCL. Cell cycle deregulation via inactivation of TP53 and of CDKN2A was a main mechanism in the histologic transformation from CLL-phase, being present in approximately half of the cases, and affected the outcome of the RS patients. A second major subgroup was characterized by the presence of trisomy 12 and comprised one third of the cases. While RS shared some of the lesions seen in de novo DLBCL, its genomic profile was clearly separate. The CLL-phase preceding RS had not a generalized increase in genomic complexity when compared with untransformed CLL, but it presented clear differences in the frequency of specific genetic lesions.
Project description:PIM serine/threonine kinases are overexpressed, translocated or amplified in multiple B-cell lymphoma types. We have explored the frequency and relevance of PIM expression in different B-cell lymphoma types, and investigated whether PIM inhibition could be a rational therapeutic approach. Increased expression of PIM2 was detected in subsets of mantle cell lymphoma (MCL), diffuse large B-cell lymphoma (DLBLC), follicular lymphoma (FL), marginal zone lymphoma-MALT type (MZL-MALT), chronic lymphocytic leukemia (CLL) and nodal marginal zone lymphoma (NMZL) cases. Increased PIM2 protein expression was associated with an aggressive clinical course in ABC-DLBCL patients. Pharmacological and genetic inhibition of PIM2 revealed p4E-BP1(Thr37/46) and p4E-BP1(Ser65) as molecular biomarkers characteristic of PIM2 activity, and indicated the involvement of PIM2 kinase in regulating mTORC1. The simultaneous genetic inhibition of all three PIM kinases induced changes in apoptosis and cell cycle. In conclusion, we show that PIM2 kinase inhibition is a rational approach in DLBCL treatment, identify appropriate biomarkers for pharmacodynamic studies, and provide a new marker for patient stratification. Gene-expression profiling was conducted in a series of 114 B-cell non-Hodgkin lymphoma patients (DLBCL, FL, MALT, MCL, CLL and NMZL). Seven freshly frozen lymph nodes and six freshly frozen reactive tonsils were used as controls.
Project description:Richter syndrome (RS) occurs in up to 15% of patients with chronic lymphocytic leukemia (CLL). While RS, usually represented by the histologic transformation to a diffuse large B-cell lymphoma (DLBCL), is associated with a very poor outcome, especially when clonally related to the pre-existing CLL, mechanisms leading to RS have not been clarified yet. To better understand the pathogenesis of RS, we analyzed a series of cases including: 59 RS, 28 CLL-phase of RS, 315 CLL and 127 de novo DLBCL. RS demonstrated a genomic complexity intermediate between CLL and DLBCL. Cell cycle deregulation via inactivation of TP53 and of CDKN2A was a main mechanism in the histologic transformation from CLL-phase, being present in approximately half of the cases, and affected the outcome of the RS patients. A second major subgroup was characterized by the presence of trisomy 12 and comprised one third of the cases. While RS shared some of the lesions seen in de novo DLBCL, its genomic profile was clearly separate. The CLL-phase preceding RS had not a generalized increase in genomic complexity when compared with untransformed CLL, but it presented clear differences in the frequency of specific genetic lesions. Genomic profiling of Richter-syndrome Chronic Lymphocytic Leukemia
Project description:PIM serine/threonine kinases are overexpressed, translocated or amplified in multiple B-cell lymphoma types. We have explored the frequency and relevance of PIM expression in different B-cell lymphoma types, and investigated whether PIM inhibition could be a rational therapeutic approach. Increased expression of PIM2 was detected in subsets of mantle cell lymphoma (MCL), diffuse large B-cell lymphoma (DLBLC), follicular lymphoma (FL), marginal zone lymphoma-MALT type (MZL-MALT), chronic lymphocytic leukemia (CLL) and nodal marginal zone lymphoma (NMZL) cases. Increased PIM2 protein expression was associated with an aggressive clinical course in ABC-DLBCL patients. Pharmacological and genetic inhibition of PIM2 revealed p4E-BP1(Thr37/46) and p4E-BP1(Ser65) as molecular biomarkers characteristic of PIM2 activity, and indicated the involvement of PIM2 kinase in regulating mTORC1. The simultaneous genetic inhibition of all three PIM kinases induced changes in apoptosis and cell cycle. In conclusion, we show that PIM2 kinase inhibition is a rational approach in DLBCL treatment, identify appropriate biomarkers for pharmacodynamic studies, and provide a new marker for patient stratification.
Project description:Follicular lymphoma (FL) is one of the most common types of indolent B-cell lymphoma in Western countries. FL commonly transforms to more aggressive diffuse large B-cell lymphoma (DLBCL) at reported frequencies between 15 - 60%. We have used microarray comparative genomic hybridisation (aCGH) at 1 Mb resolution to study copy number changes in paired tumor samples (primary FL and a subsequent tDLBCL) as well as de novo DLBCL cases to outline genetic mechanisms of transformation from follicular lymphoma to diffuse large B-cell lymphoma.
Project description:Follicular lymphoma (FL) is one of the most common types of indolent B-cell lymphoma in Western countries. FL commonly transforms to more aggressive diffuse large B-cell lymphoma (DLBCL) at reported frequencies between 15 - 60%. We have used microarray comparative genomic hybridisation (aCGH) at 1 Mb resolution to study copy number changes in paired tumor samples (primary FL and a subsequent tDLBCL) as well as de novo DLBCL cases to outline genetic mechanisms of transformation from follicular lymphoma to diffuse large B-cell lymphoma. Single hybridization per case. 21 FL, 31 transformed DLBCL, 29 de novo DLBCL (10 GC and 19 non-GC DLBCL). Tumor labelled with Cy5 and reference with Cy3. Mixture of 20 normal male or female genomic DNA was used in sex-mismatched hybridization.
Project description:Recent GWAS have identified several susceptibility loci for NHL. Despite these successes, much of the heritable variation in NHL risk remains to be explained. Common copy-number variants are important genomic sources of variability, and hence a potential source to explain part of this missing heritability. In this study, we carried out a CNV analysis using GWAS data from 681 NHL cases and 749 controls to explore the relationship between common structural variation and lymphoma susceptibility. Here we found a novel association with diffuse large B-cell lymphoma (DLBCL) risk involving a partial duplication of the C-terminus region of the LOC283177 long non-coding RNA that was further validated by quantitative PCR. For chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), known somatic deletions were identified on chromosomes 13q14, 11q22-23, 14q32 and 22q11.22. Our study shows that GWAS data can be used to identify germline CNVs associated with disease risk for DLBCL and somatic CNVs for CLL/SLL. We performed a genome-wide CNV analysis of 681 NHL cases and 749 controls from the San Francisco Bay Area, genotyped using the Illumina HumanCNV370-Duo BeadChip array. Signal intensity data in the form of log R ratio (LRR) and B allele frequency (BAF) values were obtained directly from the Beadstudio software. Quality control filtering was used to exclude unreliable samples, resulting in a final dataset of 619 NHL cases (205 FL, 242 DLBCL, 172 CLL/SLL) and 730 controls.
Project description:Genomic aberrations are of predominant importance to the biology and clinical outcome of patients with chronic lymphocytic leukemia (CLL), and FISH-based genomic risk classifications are routinely used in clinical decision making in CLL. One of the known limitations of CLL FISH is the inability to comprehensively interrogate the CLL genome for genomic changes. In an effort at overcoming the existing limitations in CLL genome analysis, we have analyzed high-purity DNA isolated from FACS-sorted CD19+ cells and paired CD3+ or buccal cells from 255 CLL patients for acquired genomic copy number aberrations (aCNA) using ultra-high-density Affymetrix SNP 6.0 arrays. Overall, two or more subchromosomal aCNA were found in 39% (100/255) of all cases analyzed, while ≥3 subchromosomal aCNA were detected in 20% (50/255) of cases. Subsequently, we have correlated genomic lesion loads (genomic complexity) with the clinical outcome measures time to first therapy (TTFT) and overall survival (OS). Using multivariate analyses incorporating the most important prognostic factors in CLL together with SNP 6.0 array-based genomic lesion loads at various thresholds, we identify elevated CLL genomic complexity as an independent and powerful marker for the identification of CLL patients with aggressive disease and short survival.
Project description:Transcriptional profiling of major types of B-cell NHL clinical samples. While comparing all the types together, their expression was compared against reactive lymph nodes, except SMZL whose expression was compared against normal splenic cells. Keywords: disease state analysis Clinical samples; 8 reactive lymph nodes, 5 splenic controls Vs 187 cases (38 MCL, 38 CLL, 9 BL, 27 SMZL, 36 DLBCL, 33 FL , 6 nMZL)