Karyotypic instability, including numerical and structural chromosomal aberrations, represents a distinct feature of multiple myeloma (MM). 40-50% of patients displayed hyperdiploidy, defined by recurrent trisomies of non-random chromosomes. To characterize hyperdiploid (H) and nonhyperdiploid (NH) MM molecularly, we analyzed the gene expression profiles of 66 primary tumors, and used FISH to investigate the major chromosomal alterations. The differential expression of 225 genes mainly involved in protein biosynthesis, transcriptional machinery and oxidative phosphorylation distinguished the 28 H-MM from the 38 NH-MM cases. The 204 upregulated genes in H-MM mapped mainly to the chromosomes involved in hyperdiploidy, and the29% up-regulated genes in NH-MM mapped to 16q. The identified transcriptional fingerprint was robustly validated on a publicly available gene expression dataset of 64 MM cases; and the global expression modulation of regions on the chromosomes involved in hyperdiploidy was verified using a self-developed non-parametric statistical method. We showed that H-MM could be further divided into two distinct molecular and transcriptional entities, characterized by the presence of trisomy 11 and 1q-extracopies/chromosome 13 deletion, respectively. Our data reinforce the importance of combining molecular cytogenetics and gene expression profiling to define a genomic framework for the study of MM pathogenesis and clinical management.
Upregulation of translational machinery and distinct genetic subgroups characterise hyperdiploidy in multiple myeloma.
Sex
View SamplesBackground and objective: The chromosome 13 deletion (del(13)) represents one of the most frequent chromosomal alterations in multiple myeloma (MM). del(13) is associated with an unfavorable prognosis, although there is an increasing agreement that its prognostic relevance has to be related to the ploidy status and the presence of different chromosomal translocations. This study is aimed at providing a comprehensive analysis of the transcriptional features of del(13) in MM. Design and methods: Highly purified plasma cells from 80 newly diagnosed MM patients were characterized by means of FISH and high-density oligonucleotide microarray for gene expression profiling and chromosomal alterations. Results: We identified 67 differentially expressed genes in the del(13)+ and del(13)- groups, all of which downregulated in the del(13)+ cases: 44 mapped along the whole chromosome 13, seven on chromosome 11 and three on chromosome 19. Functional analyses of the selected genes indicated their involvement in protein biosynthesis, ubiquitination and transcriptional regulation. An integrative genomic approach based on regional analyses of the gene expression data identified distinct chromosomal regions whose global expression modulation could differentiate del(13)+, in particular the upregulation of 1q21-1q42 and the downregulation of 19p and almost the entire chromosome 11. FISH analyses confirmed the close relationship between del(13)+ and the presence of extracopies of 1q21-1q42 (P=6x10-4) or the absence of chromosome 11 and 19 trisomy (P=5x10-4). Interpretation and conclusions: Our results indicate that distinct types of chromosomal aberrations are closely related to the transcriptional profiles of del(13)+, suggesting that the contribution of del(13) on the malignancy should be considered together with associated abnormalities.
Integrative genomic analysis reveals distinct transcriptional and genetic features associated with chromosome 13 deletion in multiple myeloma.
Sex
View SamplesIn order to investigate the patterns of genetic lesions in a panel of 23 Human Multiple Myeloma Cell Lines (HMCLs), we made a genomic integrative analysis involving FISH and both gene expression and genome-wide profiling approaches. The expression profiles of the genes targeted by the main IGH translocations showed that the WHSC1/MMSET gene involved in t(4;14)(p16;q32) was expressed at different levels in all of the HMCLs, and that the expression of the MAF gene was not restricted to the HMCLs carrying t(14;16)(q32;q23). Supervised analyses identified a limited number of genes specifically associated with t(4;14) and involved in different biological processes. The signature related to MAF/MAFB expression included the known MAF target genes CCND2 and ITGB7, as well as genes controlling cell shape and cell adhesion. Genomewide DNA profiling allowed the identification of a gain on chromosome arm 1q in 88% of the analyzed cell lines, together with recurrent gains on 8q, 18q, 7q and 20q; the most frequent deletions affected 1p, 13q, 17p and 14q; and almost all of the cell lines presented LOH on chromosome 13. Two hundred and twenty-two genes were found to be simultaneously overexpressed and amplified in our panel, including the BCL2 locus at 18q21.33. Our data further support the evidence of the genomic complexity of multiple myeloma and reinforce the role of an integrated genomic approach in improving our understanding of the molecular pathogenesis of the disease.
Molecular characterization of human multiple myeloma cell lines by integrative genomics: insights into the biology of the disease.
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View SamplesDistinct genetic abnormalities such as TP53 deletion at 17p13.1, have been identified as having an adverse prognostic relevance in B-cell chronic lymphocytic leukemia (B-CLL). Conventional cytogenetic studies have shown that TP53 deletion in B-CLL is associated predominantly with 17p loss resulting from complex chromosomal rearrangements. We performed genome-wide DNA (SNPs arrays), fluorescence in situ hybridization (FISH) and gene expression profiling (GEP) analyses to investigate the significance of 17p loss in a panel of 71 genetically well-characterized B-CLLs in Binet stage A, 18 of which carried a TP53 monoallelic deletion. Combined SNP arrays and FISH approaches showed 17p loss in all of the TP53-deleted cases, with breakpoints scattered along the 17p11.2 region. Mutations in exons 5 to 9 of TP53 were found in 9/12 deleted samples. GEP of 60 B-CLLs, including 7 patients with 17p loss, identified 40 differentially expressed genes in 17p- versus 17p normal samples, 35 of which were down-regulated in 17p- tumors. The majority (30/35) of these transcripts, including putative tumor suppressor genes, mapped to 17p. Overall, these data indicate that, beside TP53 deletion, the concomitant loss of 17p arm may contribute to the strong negative prognostic impact known to be associated with this lesion in B-CLL.
Molecular and transcriptional characterization of 17p loss in B-cell chronic lymphocytic leukemia.
Sex
View SamplesDistinct genetic abnormalities such as TP53 deletion at 17p13.1, have been identified as having an adverse prognostic relevance in B-cell chronic lymphocytic leukemia (B-CLL). Conventional cytogenetic studies have shown that TP53 deletion in B-CLL is associated predominantly with 17p loss resulting from complex chromosomal rearrangements. We performed genome-wide DNA (SNPs arrays), fluorescence in situ hybridization (FISH) and gene expression profiling (GEP) analyses to investigate the significance of 17p loss in a panel of 71 genetically well-characterized B-CLLs in Binet stage A, 18 of which carried a TP53 monoallelic deletion. Combined SNP arrays and FISH approaches showed 17p loss in all of the TP53-deleted cases, with breakpoints scattered along the 17p11.2 region. Mutations in exons 5 to 9 of TP53 were found in 9/12 deleted samples. GEP of 60 B-CLLs, including 7 patients with 17p loss, identified 40 differentially expressed genes in 17p- versus 17p normal samples, 35 of which were down-regulated in 17p- tumors. The majority (30/35) of these transcripts, including putative tumor suppressor genes, mapped to 17p. Overall, these data indicate that, beside TP53 deletion, the concomitant loss of 17p arm may contribute to the strong negative prognostic impact known to be associated with this lesion in B-CLL.
Molecular and transcriptional characterization of 17p loss in B-cell chronic lymphocytic leukemia.
Sex
View SamplesThe cerebral cortex underwent a rapid expansion and complexification during recent primate evolution, but the underlying developmental mechanisms remain essentially unknown.
Genes expressed in specific areas of the human fetal cerebral cortex display distinct patterns of evolution.
Age, Specimen part
View SamplesSaturated fatty acids (SFA) are widely thought to induce inflammation in adipose tissue (AT), while monounsaturated fatty acids (MUFA) are purported to have the opposite effect; however, it is unclear if individual SFA and MUFA behave similarly. Our goal was to examine adipocyte transcriptional networks regulated by individual SFA (palmitic acid, PA; stearic acid, SA) and MUFA (palmitoleic acid, PMA; oleic acid, OA).
Individual saturated and monounsaturated fatty acids trigger distinct transcriptional networks in differentiated 3T3-L1 preadipocytes.
Specimen part
View SamplesWhole blood (paxgene) gene expression was measured using Affymetrix microarray from 377 individuals with rheumatoid arthritis.
Integrative genomic deconvolution of rheumatoid arthritis GWAS loci into gene and cell type associations.
Sex, Age, Specimen part, Disease
View SamplesTo identify metastasis suppressor genes, which are functionally compromised in late-stage breast cancer, we compared the gene expression profiles of an established breast cancer progression cell line model and leveraged large amounts of publically available data by applying multiple bioinformatics filters. Here we report the identification of serum deprivation response (SDPR, also known as cavin-2) as a bona fide metastasis suppressor, capable of impairing the metastatic growth of cancer cells while having no effect on the growth of primary tumors.
SDPR functions as a metastasis suppressor in breast cancer by promoting apoptosis.
Disease, Disease stage, Cell line
View SamplesIL13R2 overexpression promotes metastasis of basal-like breast cancers
Targeting IL13Ralpha2 activates STAT6-TP63 pathway to suppress breast cancer lung metastasis.
Specimen part, Cell line, Treatment
View Samples