Project description:The aim of the project was to detect genomic regions that were normal, duplicated or deleted in these cell lines for transcription factors NFKBp50, NFkBp65, HIF1a and FAS gene which we studied. It is not clear the effects of copy number variations on allele specific assembly or disruption of master regulator transcription factors. Thus, the CNV analysis verified that 16HBE cell line, though transformed with defective simian virus, had normal copy number variations thus was a suitable source for nuclear extract to study the afore mentioned TFs. T84 showed duplications and large genomic deletions for TFs: NFkBp50 and p65. 16HBE and T84 are both epithelial cell lines type from human. 16HBE is derived from bronchial epithelium, while the T84 is derived from the colon carcinoma.
Project description:aCGH was performed on acute myeloid leukemia samples (vs constitutive Normal matched tissue) derived from a mouse model of mutant NPM1, NRAS and FLIT3 normal karyotype leukemia. The purpose of these assays was to identify common and potentially co-operative genetic phenomena in NPM1c positive mouse leukemias.
Project description:Patients diagnosed with acute myeloid leukemia with complex karyotype (CK AML) have an adverse prognosis using current therapies, especially when accompanied by TP53 alterations. We hereby report the RNA-sequencing analysis of the 68 CK AML samples included in the Leucegene 415 patient cohort. We confirm the frequent occurrence of TP53 alterations in this subgroup and further characterize the allele expression profile and transcript alterations of this gene. We also document that the RAS pathway (N/KRAS, NF1, PTPN11, BRAF) is frequently altered in this disease. Targeted chemical interrogation of genetically characterized primary CK AML samples identifies polo-like kinase 1 (PLK1) inhibitors as the most selective agents for this disease subgroup. TP53 status did not alter sensitivity to PLK1 inhibitors. Interestingly, CK AML specimens display a G2/M transcriptomic signature that includes higher expression levels of PLK1 and correlates with PLK1 inhibition sensitivity. Together, our results highlight vulnerability in CK AML. In line with these in vitro data, volasertib shows a strong anti-AML activity in xenotransplantation mouse models of human adverse AML. Considering that PLK1 inhibitors are currently being investigated clinically in AML and myelodysplastic syndromes, our results provide a new rationale for PLK1-directed therapy in patients with adverse cytogenetic AML.
Project description:Recurrences of diffuse large B-cell lymphomas (DLBCL) result in significant morbidity and mortality, but their underlying genetic and biological mechanisms are unclear. Clonal relationship in DLBCL relapses so far is mostly addressed by the investigation of immunoglobulin (IG) rearrangements, therefore lacking deeper insights into genome-wide lymphoma evolution. We studied mutations and copy number aberrations in 20 paired relapsing and 20 non-relapsing DLBCL cases aiming to test the clonal relationship between primaries and relapses, to track tumorsâ genetic evolution and to investigate the genetic background of DLBCL recurrence. Three clonally-unrelated DLBCL relapses were identified (15%). Also, two distinct patterns of genetic evolution in clonally-related relapses were detected: (1) early-divergent/branching evolution from a common progenitor in 6 patients (30%), and (2) late-divergent/linear progression of relapses in 11 patients (65%). Analysis of recurrent genetic events identified potential early drivers of lymphomagenesis (KMT2D, MYD88, CD79B and PIM1). The most frequent relapse-specific events were additional mutations in KMT2D and alterations of MEF2B. SOCS1 mutations were exclusive to non-relapsing DLBCL, whereas primaries of relapsing DLBCL more commonly displayed gains of 10p15.3-p12.1 containing the potential oncogenes PRKCQ, GATA3, MLLT10 and ABI1. Altogether, our study expands knowledge on clonal relationship, genetic evolution and mutational basis of DLBCL relapses. There are 62 copy number Agilent 180k SurePrint arrays in total, which represent 40 cases. There are 21 arrays of primary relapsing DLBCL tumors, 21 arrys of matched relapses and 20 arrays of non relapsing DLBCLs.
Project description:Glioblastoma multiforme (GBM), the most common and malignant type of glioma, is characterized by a poor prognosis and the lack of an effective treatment, which are due to a small sub-population of cells with stem-like properties, termed glioma stem cells (GSCs). The term M-bM-^@M-^\multiformeM-bM-^@M-^] describes the histological feature of this tumor, i.e. the cellular and morphological heterogeneity. At the molecular level multiple layers of alterations may reflect this heterogeneity providing together the driving force of tumor initiation and development. In order to decipher the common M-bM-^@M-^\signatureM-bM-^@M-^] of the ancestral GSC population, we examined 5 already characterized GSC lines evaluating their copy number alterations using a genome-wide approach. Genomic DNA was isolated from 5 Glioma Stem Cell (GSC) lines. Each sample was labeled with Cy3 dye and then hybridized against the same commercial reference DNA labeled in Cy5.
Project description:Protein S-nitrosation (SNO-protein) is a post-translational modification in which a cysteine (Cys) residue is modified by nitric oxide (SNO-Cys). SNO-proteins impact many biological systems, but their identification has been technically challenging. We developed a chemical proteomic strategy - SNOTRAP (SNO trapping by triaryl phosphine) -that allows improved identification of SNO-proteins by mass spectrometry. We found that S-nitrosation is elevated during early stages of neurodegeneration, preceding cognitive decline. We identified changes in the SNOproteome during early neurodegeneration that are potentially relevant for synapse function, metabolism, and Alzheimer’s disease pathology. SNO-proteome analysis further reveals a potential linear motif for SNO-Cys sites that are altered during neurodegeneration. Our strategy can be applied to multiple cellular and disease contexts and can reveal signaling networks that aid drug development.
Project description:A subset of myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) show complex karyotype (CK), and these cases include a relatively high proportion of cases of therapy-related myeloid neoplasms and TP53 mutations. We aimed to evaluate the clinicopathologic features of outcome of 299 AML and MDS patients with CK collected from multiple academic institutions. Mutations were present in 287 patients (96%), and the most common mutation detected was in TP53 gene (247, 83%). A higher frequency of TP53 mutations was present in therapy-related cases (P = .008), with a trend for worse overall survival (OS) in therapy-related patients as compared with de novo disease (P = .08) and within the therapy-related group; the presence of TP53 mutation strongly predicted for worse outcome (P = .0017). However, there was no difference in survival between CK patients based on categorization of AML vs MDS (P = .96) or presence of absence of circulating blasts ≥1% (P = .52). TP53-mutated patients presented with older age (P = .06) and lower hemoglobin levels (P = .004) and marrow blast counts (P = .02) compared with those with CK lacking TP53 mutation. Multivariable analysis identified presence of multihit TP53 mutation as strongest predictor of worse outcome, whereas neither a diagnosis of AML vs MDS nor therapy-relatedness independently influenced OS. Our findings suggest that among patients with MDS and AML, the presence of TP53 mutation (in particular multihit TP53 mutation) in the context of CK identifies a homogeneously aggressive disease, irrespective of the blast count at presentation or therapy-relatedness. The current classification of these cases into different disease categories artificially separates a single biologic disease entity.
Project description:Acute myeloid leukemia with complex karyotype (CK-AML) is characterized by three or more chromosomal aberrations, and comprises 10–12% of AML patients. It is associated with complex chromosomal rearrangements, intra-tumor heterogeneity, therapy resistance and poor overall survival. We aimed to transcriptionally characterize CK-AML by performing RNA sequencing on blasts from 4 CK-AML patient samples.
Project description:We conducted a cytogenetic analysis of 642 children with de novo acute myeloid leukemia (AML) treated on the AML-Berlin-Frankfurt-Münster (BFM) 04 protocol to determine the prognostic value of specific chromosomal aberrations including monosomal (MK+), complex (CK+) and hypodiploid (HK+) karyotypes, individually and in combination. Multivariate regression analysis identified in particular MK+ (n=22) as a new independent risk factor for poor event-free survival (EFS 23±9% vs 53±2% for all other patients, P=0.0003), even after exclusion of four patients with monosomy 7 (EFS 28±11%, P=0.0081). CK+ patients without MK had a better prognosis (n=47, EFS 47±8%, P=0.46) than those with MK+ (n=12, EFS 25±13%, P=0.024). HK+ (n=37, EFS 44±8% for total cohort, P=0.3) influenced outcome only when t(8;21) patients were excluded (remaining n=16, EFS 9±8%, P<0.0001). An extremely poor outcome was observed for MK+/HK+ patients (n=10, EFS 10±10%, P<0.0001). Finally, isolated trisomy 8 was also associated with low EFS (n=16, EFS 25±11%, P=0.0091). In conclusion, monosomal karyotype is a strong and independent predictor for high-risk pediatric AML. In addition, isolated trisomy 8 and hypodiploidy without t(8;21) coincide with dismal outcome. These results have important implications for risk stratification and should be further validated in independent pediatric cohorts.