Project description:Lymphoplasmacytic lymphomas and marginal zone lymphomas of nodal, extra-nodal and splenic types account for 10% of non-Hodgkin lymphomas. They are similar at the cell differentiation level, sometimes making difficult to distinguish them from other indolent non-Hodgkin lymphomas. To better characterize their genetic basis, we performed array-based comparative genomic hybridization in 101 marginal zone lymphomas (46 MALT, 35 splenic and 20 nodal marginal zone lymphomas) and 13 lymphoplasmacytic lymphomas. Overall, 90.1% exhibited copy-number abnormalities. Lymphoplasmacytic lymphomas demonstrated the most complex karyotype (median=7 copy-number abnormalities), followed by MALT (4), nodal (3.5) and splenic marginal zone lymphomas (3). A comparative analysis exposed a group of copy-number abnormalities shared by several or all the entities with few disease-specific abnormalities. Gain of chromosomes 3, 12 and 18 and loss of 6q23-q24 (TNFAIP3) were identified in all entities. Losses of 13q14.3 (MIRN15A-MIRN16-1) and 17p13.3-p12 (TP53) were found in lymphoplasmacytic and splenic marginal zone lymphomas; loss of 11q21-q22 (ATM) in nodal, splenic marginal zone and lymphoplasmacytic lymphomas; loss of 7q32.1-q33 in MALT, splenic and lymphoplasmacytic lymphomas. Abnormalities affecting the NF-kB pathway were observed in 70% of MALT and lymphoplasmacytic lymphomas and 30% of splenic and nodal marginal zone lymphomas, suggesting distinct roles of this pathway in the pathogenesis/progression of these subtypes. Elucidation of the genetic alterations contributing to the pathogenesis of these lymphomas may guide to design specific therapeutic approaches.
Project description:Lymphoplasmacytic lymphomas and marginal zone lymphomas of nodal, extra-nodal and splenic types account for 10% of non-Hodgkin lymphomas. They are similar at the cell differentiation level, sometimes making difficult to distinguish them from other indolent non-Hodgkin lymphomas. To better characterize their genetic basis, we performed array-based comparative genomic hybridization in 101 marginal zone lymphomas (46 MALT, 35 splenic and 20 nodal marginal zone lymphomas) and 13 lymphoplasmacytic lymphomas. Overall, 90.1% exhibited copy-number abnormalities. Lymphoplasmacytic lymphomas demonstrated the most complex karyotype (median=7 copy-number abnormalities), followed by MALT (4), nodal (3.5) and splenic marginal zone lymphomas (3). A comparative analysis exposed a group of copy-number abnormalities shared by several or all the entities with few disease-specific abnormalities. Gain of chromosomes 3, 12 and 18 and loss of 6q23-q24 (TNFAIP3) were identified in all entities. Losses of 13q14.3 (MIRN15A-MIRN16-1) and 17p13.3-p12 (TP53) were found in lymphoplasmacytic and splenic marginal zone lymphomas; loss of 11q21-q22 (ATM) in nodal, splenic marginal zone and lymphoplasmacytic lymphomas; loss of 7q32.1-q33 in MALT, splenic and lymphoplasmacytic lymphomas. Abnormalities affecting the NF-kB pathway were observed in 70% of MALT and lymphoplasmacytic lymphomas and 30% of splenic and nodal marginal zone lymphomas, suggesting distinct roles of this pathway in the pathogenesis/progression of these subtypes. Elucidation of the genetic alterations contributing to the pathogenesis of these lymphomas may guide to design specific therapeutic approaches. One hundred fourteen patients were included in this study: 46 MALT lymphomas (22 pulmonary, 11 salivary glands, 7 lacrimal glands and 6 gastrointestinal), 35 splenic marginal zone lymphomas, 20 nodal marginal zone lymphomas and 13 non-Waldenström’s Macroglobulinemia lymphoplasmacytic lymphomas. All cases were reviewed prior to study on paraffin sections with immunohistochemistry. Sections of each frozen tissue used for study were also reviewed by histological examination and immunohistochemistry before was submitted for the study.
Project description:Using high-resolution genomic microarray analysis, a distinct genomic profile was defined in 114 samples from patients with splenic marginal zone lymphoma (SMZL). Notably, deletion or uniparental disomy of chromosome 7q were detected in 39% of SMZLs but in only 9 of 170 (5%) mature B-cell lymphomas (p<10-6). The presence of unmutated IgVH genes, genomic complexity, 17p13-P53 deletion and 8q gain including MYC gene, but not 7q deletion, were correlated with shorter overall survival. Extensive mapping analyses narrowed down the commonly deleted region to 2.7 Mb. in 7q32.1-q32.2 from SND1 to COPG2 genes. High-throughput sequencing analysis of the 7q32 deleted segment in SMZL cells did not identify bi-allelic deletions, insertions or clear pathogenic mutations, but detected six single nucleotide changes in IRF5 (n=2), TMEM209 (n=2), CALU (n=1) and ZC3HC1 (n=1). Comparative expression analysis found that IRF5, TMEM209 and CALU genes had down-regulated expression in lymphomas with 7q32 deletion vs. non-deleted tumors. Ectopic expression of IRF5 in marginal-zone lymphoma cells decreased cell proliferation and induced apoptosis. These results indicate that small deletions, insertions and/or point mutations inactivating genes within 7q32 are not common events in SMZL. Further studies are required to evaluate the putative role of IRF5 in SMZL pathogenesis. 9 samples. 6 patient samples with 7q32 deletion and 3 patient samples without 7q32 deletion. Splenic Marginal Zone Lymphoma patient samples with 7q32 deletion vs. Splenic Marginal Zone Lymphoma patient samples without 7q32 deletion
Project description:Using high-resolution genomic microarray analysis, a distinct genomic profile was defined in 114 samples from patients with splenic marginal zone lymphoma (SMZL). Notably, deletion or uniparental disomy of chromosome 7q were detected in 39% of SMZLs but in only 9 of 170 (5%) mature B-cell lymphomas (p<10-6). The presence of unmutated IgVH genes, genomic complexity, 17p13-P53 deletion and 8q gain including MYC gene, but not 7q deletion, were correlated with shorter overall survival. Extensive mapping analyses narrowed down the commonly deleted region to 2.7 Mb. in 7q32.1-q32.2 from SND1 to COPG2 genes. High-throughput sequencing analysis of the 7q32 deleted segment in SMZL cells did not identify bi-allelic deletions, insertions or clear pathogenic mutations, but detected six single nucleotide changes in IRF5 (n=2), TMEM209 (n=2), CALU (n=1) and ZC3HC1 (n=1). Comparative expression analysis found that IRF5, TMEM209 and CALU genes had down-regulated expression in lymphomas with 7q32 deletion vs. non-deleted tumors. Ectopic expression of IRF5 in marginal-zone lymphoma cells decreased cell proliferation and induced apoptosis. These results indicate that small deletions, insertions and/or point mutations inactivating genes within 7q32 are not common events in SMZL. Further studies are required to evaluate the putative role of IRF5 in SMZL pathogenesis. Affymetrix GeneChip 50k-XbaI and/or 250-NspI/StyI SNP microarrays were performed for 59 SMZL samples and 4 Marginal Zone cell lines according to the manufacturer's directions.
Project description:Nodal marginal zone lymphoma (NMZL) is a small B cell neoplasm whose molecular pathogenesis is still essentially unknown and whose differentiation from other small B cell lymphomas is hampered by the lack of specific markers. We have analyzed gene expression, miRNA profile and copy number data from 15 NMZL cases. For comparison, 16 follicular lymphomas, 9 extranodal marginal zone lymphomas, 8 reactive lymph nodes and B-cell subtypes were included. The results were validated by qRT-PCR in an independent series including 61 paraffin-embedded NMZLs. NMZL signature showed an enriched expression of gene sets identifying interleukins, integrins, CD40, PI3K, NF-kB and TGF-Beta; and included genes expressed by normal marginal zone cells and memory B cells. The most highly overexpressed genes were SYK, TACI, CD74, CD82 and CDC42EP5. Genes linked to G2/M and germinal center were downregulated. Comparison of the gene expression profiles of NMZL and FL showed enriched expression of CHIT1, TGFB1 and TACI in NMZL, and BCL6, LMO2 and CD10 in FL. NMZL displayed increased expression of miR-221, miR-223 and let-7f, while FL strongly expressed miR-494. Our study identifies new candidate diagnostic molecules for NMZL and reveals survival pathways activated in NMZL. We have analyzed gene expression, miRNA profile and copy number data from 15 NMZL cases. For comparison, 16 follicular lymphomas, 9 extranodal marginal zone lymphomas, 8 reactive lymph nodes and B-cell subtypes were included. The results were validated by qRT-PCR in an independent series including 61 paraffin-embedded NMZLs
Project description:Ocular adnexal lymphoma is a rare subtype of non-Hodgkin lymphoma. DIA LC-MS of serum samples collected at diagnosis was performed on 38 ocular adnexal lymphomas (28 extranodal marginal zone lymphomas, and 10 diffuse large B-cell lymphomas), and 20 controls (10 idiopathic orbital inflammation, and 10 reactive lymphoid hyperplasia). Complete clinicopathologic features of these patients were collected.
Project description:Unique and shared cytogenetic abnormalities have been documented for marginal zone lymphomas (MZLs) arising at different sites. Recently, homozygous deletions of the chromosomal band 6q23, involving the tumor necrosis factor alpha-induced protein 3 (TNFAIP3, A20) gene, a negative regulator of NF-kappa B, were described in ocular adnexal MZL, suggesting a role for A20 as a tumor suppressor in this disease entity. Here, we investigated inactivation of A20 by DNA mutations or deletions in a panel of extranodal (EMZL), nodal (NMZL) and splenic (SMZL) MZLs. Inactivating mutations encoding truncated A20 proteins were identified in 6/32 (18.8%) MZLs, including 3/11 (27.3%) EMZLs, 2/9 (22.2%) NMZLs, and 1/12 (8.3%) SMZLs. Two additional unmutated non-splenic MZLs also showed mono- or biallelic A20 deletions by FISH and/or array-CGH. Thus, A20 loss by both somatic mutations and/or deletions represents a common genetic aberration across all MZL subtypes, which may contribute to lymphomagenesis by inducing constitutive NF-kappa B activation. Keywords: Genome variation profiling by SNP array 27 MZL samples. No technical replications.
Project description:Using high-resolution genomic microarray analysis, a distinct genomic profile was defined in 114 samples from patients with splenic marginal zone lymphoma (SMZL). Notably, deletion or uniparental disomy of chromosome 7q were detected in 39% of SMZLs but in only 9 of 170 (5%) mature B-cell lymphomas (p<10-6). The presence of unmutated IgVH genes, genomic complexity, 17p13-P53 deletion and 8q gain including MYC gene, but not 7q deletion, were correlated with shorter overall survival. Extensive mapping analyses narrowed down the commonly deleted region to 2.7 Mb. in 7q32.1-q32.2 from SND1 to COPG2 genes. High-throughput sequencing analysis of the 7q32 deleted segment in SMZL cells did not identify bi-allelic deletions, insertions or clear pathogenic mutations, but detected six single nucleotide changes in IRF5 (n=2), TMEM209 (n=2), CALU (n=1) and ZC3HC1 (n=1). Comparative expression analysis found that IRF5, TMEM209 and CALU genes had down-regulated expression in lymphomas with 7q32 deletion vs. non-deleted tumors. Ectopic expression of IRF5 in marginal-zone lymphoma cells decreased cell proliferation and induced apoptosis. These results indicate that small deletions, insertions and/or point mutations inactivating genes within 7q32 are not common events in SMZL. Further studies are required to evaluate the putative role of IRF5 in SMZL pathogenesis. CGH analysis was performed for 76 Splenic Marginal Zone lymphoma patient samples. Production and validation of the array, hybridization methods and analytical procedures have been described elsewhere: Snijder AM, Nowak N, Segraves R, et al. Assembly of microarrays for genome-wide measurement of DNA copy number. Nat Genet. 2001;29:263-264.
Project description:Nodal marginal zone lymphoma (NMZL) is a rare small B cell lymphoma lacking disease-defining phenotype and precise diagnostic markers. To better understand the mutational landscape of NMZL, particularly in comparison to other small nodal B cell lymphomas, we performed whole exome sequencing, targeted high throughput sequencing and array comparative genomic hybridization on a retrospective series. Our study identified for the first time recurrent, diagnostically useful and potentially therapeutically relevant BRAF mutations in NMZL. Sets of somatic mutations that could help to discriminate NMZL from other closely related small B cell lymphomas were uncovered and tested on unclassifiable small B cell lymphoma cases, in which clinical, morphological and phenotypical features were equivocal. Application of targeted gene panel sequencing gave at many occasions valuable clues for more specific classification.