Project description:We combined mRNA, small RNA and ribosome methylation sequencing to investigate snoRNA expression patterns in multiple myeloma and their association with different chromosomal aberrations. We identified snoRNAs dysregulated in molecular subgroups, with SNORD78 being highly expressed in gain1q patients and associated with poor prognosis. Our study shows that the expression of particular snoRNAs and methylation of specific snoRNA-guided rRNA sites are associated with specific chromosome gains, which are common elements in multiple myeloma.
Project description:We combined mRNA, small RNA and ribosome 2'O-methylation sequencing to investigate snoRNA expression patterns in multiple myeloma and their association with different chromosomal aberrations. We identified snoRNAs dysregulated in molecular subgroups, with SNORD78 being highly expressed in gain1q patients and associated with poor prognosis. Our study shows that the expression of particular snoRNAs and methylation of specific snoRNA-guided rRNA sites are associated with specific chromosome gains, which are common elements in multiple myeloma.
Project description:Mechanisms of immune regulation may control proliferation of aberrant plasma cells (PCs) in patients with the asymptomatic monoclonal gammopathy of undetermined significance (MGUS) preventing progression to active multiple myeloma (MM). We investigated the role of CD85j (LILRB1), an inhibitory immune checkpoint for B cell function, in MM pathogenesis. We used microarrays to gain insight into the molecular mechanisms underlying CD85j functions in myeloma cells.
Project description:Primary plasma cell leukemia (pPCL) is a rare and aggressive variant of multiple myeloma (MM), which is associated with a very poor prognosis. Specific molecular patterns distinguish pPCL in comparison to MM and in relation to main genomic alterations. In the present study, a whole-genome methylation profiling analysis by high-density array revealed a global gene hypomethylation profile in pPCL. Lower methylation levels were particularly observed in the promoter and 5’ untranslated regions (5’UTR), whereas higher levels were evidenced in gene body or 3’ untranslated regions (3’UTR). CpG islands (CGI) resulted largely hypomethylated, whereas higher methylation levels were observed in CGI distal regions. Peculiar differential methylation patterns were identified in association to major chromosomal aberrations and DIS3 mutational status and involved genes playing roles in cell migration, bone metabolism, transcription regulation or DNA damage response. Finally, decreasing methylation levels were evidenced for few genes in association to MM disease progression, from healthy condition to MM and pPCL. Our data may provide new insights into the molecular characterization of pPCL patients, thus being potentially useful in the prognostic stratification or identification of novel molecular targets.
Project description:Objectives: Earlier studies involving a priori gene selection have identified promoter regions deregulated by DNA methylation changes in oral squamous cell cancers (OSCCs) and precancers. Interrogation of global DNA methylation patterns for such specimens has not been reported, though such analyses are needed to uncover novel molecular factors driving disease. Materials and Methods: We evaluated global DNA methylation patterns for 30 biopsies obtained from 10 patients undergoing surgical removal of an OSCC or carcinoma in situ (CIS). From a disease field in each patient, we collected i) dysplastic, ii) CIS or OSCC, and iii) adjacent normal biopsies. DNA isolated from each biopsy was profiled for methylation status using the Illumina HumanMethylation27K platform. Results: Our data demonstrate that aberrant methylation of promoter CpG islands exists across oral precancer and OSCC genomes. Non-hierarchical clustering of all methylation data revealed distinct methylation patterns between the normal and the CIS/OSCC tissues (with results for dysplastic biopsies split between groups). Multiple genes exhibiting recurrent aberrant DNA methylation were found for both dysplastic and CIS/OSCC groups, and included enrichment for genes found in the WNT and MAPK signaling pathways. Conclusion: In identifying aberrant DNA methylation at the earliest stages of oral precancer and finding recurring epigenetic disruption of specific genes/pathways across our analyzed cohort, we conclude that CpG methylation changes are a hallmark of oral cancer progression and that global DNA methylation analyses are an essential component for wider studies seeking to derive biomarkers or potentially druggable targets for improving oral cancer outcomes. Bisulphite converted DNA from the 30 samples were hybridised to the Illumina Infinium 27k Human Methylation BeadChip v1.2. Total RNA from 30 oral cancer samples were hybridized to Agilent 4x44k gene expression microarray.
Project description:A major driver of multiple myeloma is thought to be aberrant signaling, yet no kinase inhibitors have proven successful in the clinic. Here, we employ an integrated, systems approach combining phosphoproteomic and transcriptome analysis to dissect cellular signaling in multiple myeloma to inform precision medicine strategies. Collectively, these predictive models identify vulnerable signaling signatures and highlight surprising differences in functional signaling patterns between <I>NRAS</I> and <I>KRAS</I> mutants invisible to the genomic landscape. Transcriptional analysis suggests that aberrant MAPK pathway activation is only present in a fraction of <I>RAS</I>-mutated vs. WT <I>RAS</I> patients. These high-MAPK patients, enriched for <I>NRAS</I> Q61 mutations, have inferior outcomes whereas <I>RAS</I> mutations overall carry no survival impact. We further develop an interactive software tool to relate pharmacologic and genetic kinase dependencies in myeloma. These results may lead to improved stratification of MM patients in clinical trials while also revealing unexplored modes of Ras biology.
Project description:We have used genome-wide methylation microarrays to analyze differences in CpG methylation patterns in cells relevant to the pathogenesis of myeloma plasma cells, including B cells, normal plasma cells, MGUS, presentation myeloma, and plasma cell leukemia (PCL). We show that methylation patterns in these cell types are capable of distinguishing non-malignant from malignant cells and that the main reason for this difference is hypomethylation of the genome at the transition from MGUS to presentation myeloma. In addition, gene-specific hypermethylation was evident at the myeloma stage. Differential methylation was also evident at the transition from myeloma to PCL with re-methylation of the genome, specifically of genes involved in cell-cell signaling and cell adhesion, which may contribute to independence from the bone marrow microenvironment. There was a high degree of methylation variability within presentation myeloma samples and this was associated with the cytogenetic differences between samples. More specifically, we found that methylation subgroups were defined by translocations and hyperdiploidy, with t(4;14) myeloma having the largest impact on DNA methylation. Two groups of hyperdiploid samples were identified, based on unsupervised clustering, which had an impact on overall survival. Overall, DNA methylation has a large impact on disease progression and on myeloma cytogenetic subgroups.
Project description:Objectives: Earlier studies involving a priori gene selection have identified promoter regions deregulated by DNA methylation changes in oral squamous cell cancers (OSCCs) and precancers. Interrogation of global DNA methylation patterns for such specimens has not been reported, though such analyses are needed to uncover novel molecular factors driving disease. Materials and Methods: We evaluated global DNA methylation patterns for 30 biopsies obtained from 10 patients undergoing surgical removal of an OSCC or carcinoma in situ (CIS). From a disease field in each patient, we collected i) dysplastic, ii) CIS or OSCC, and iii) adjacent normal biopsies. DNA isolated from each biopsy was profiled for methylation status using the Illumina HumanMethylation27K platform. Results: Our data demonstrate that aberrant methylation of promoter CpG islands exists across oral precancer and OSCC genomes. Non-hierarchical clustering of all methylation data revealed distinct methylation patterns between the normal and the CIS/OSCC tissues (with results for dysplastic biopsies split between groups). Multiple genes exhibiting recurrent aberrant DNA methylation were found for both dysplastic and CIS/OSCC groups, and included enrichment for genes found in the WNT and MAPK signaling pathways. Conclusion: In identifying aberrant DNA methylation at the earliest stages of oral precancer and finding recurring epigenetic disruption of specific genes/pathways across our analyzed cohort, we conclude that CpG methylation changes are a hallmark of oral cancer progression and that global DNA methylation analyses are an essential component for wider studies seeking to derive biomarkers or potentially druggable targets for improving oral cancer outcomes.