Project description:Germline RUNX1 mutations are found in familial platelet disorders with predisposition to acute myelogenous leukemia (FPD/AML). This very rare disease is characterized by thrombocytopenia, platelet dysfunction and a 35% lifetime risk of developing MDS/AML and in rare cases also T-ALL. Here, we focus on a case of a man with a familial history of RUNX1 R174Q mutation who developed at the age of 42 years an EGIL T2-ALL and, two years after remission, an AML-M0. To investigate whether initial and relapsed leukemic blasts originated from the same clone, we performed CGH array and WES on both blasts populations. In both T2-ALL and AML-M0 samples, CGH array revealed loss of 1p36.32-23 and 17q11.2 and nine other small deletions. Both AML-M0 and T2-ALL blasts demonstrated clonal rearrangements of both TCRγ (Vγ9-Jγ1-1) and TCRδ (Dδ2-Jδ1 and Dδ2-Jδ3). 18 genes were found by WES to be mutated in both blasts at a frequency of more than 40%. Additional variants were identified only in T2-ALL or in AML-M0 evoking the existence of a common original clone, which gave rise to subclonal populations. MiSeq technology performed on peripheral blood-derived CD34+ cells five years prior T2-ALL development revealed only missense TET2 P1962T mutation at a frequency of 1% (which reaches a frequency of 50 % in fully transformed leukemic clone) suggesting that this mutation in association with germline RUNX1 R174Q mutation led to amplification of a hematopoietic clone susceptible to acquire other transforming alterations. Identification of clonal hematopoiesis with acquired mutations at low frequency in hematopoietic progenitors before leukemia development could clearly serve as a marker of pre-leukemic state and be helpful in patient care.
Project description:We investigated a cohort of 34 archival cutaneous melanoma samples by Agilent 40 kb-resolution CGH array. We found a non-random distribution of precise CNAs predictive for clinical outcome. Although most of the alterations defined in this study have been already reported, we mapped novel melanoma-specific CNAs at highest accuracy. Moreover, our data revealed distinct amplifications hotspots, some of which were validated by quantitative real-time PCR, enabling the identification of novel melanoma oncogenic candidates. Keywords: Cutaneous melanoma, Copy number alterations, Biomarkers, FFPE We examined 34 primary melanoma formalin-fixed and paraffin-embedded (FFPE) samples by using array comparative genomic hybridization (aCGH) for DNA copy number alterations (CNAs). Genomic DNA was extracted, referred to a sex-matched diploid commercial control DNA (Promega Corporation, Madison, WI, cat. G1417 and G1521), and hybridized on the Agilent SurePrint G3 Human CGH Microarray 8x60k, cat. G4827A.
Project description:Papillary renal cell carcinomas (pRCC) are the second most common form of renal carcinoma, after clear cell Renal carcinoma (ccRCC). PRCC account for 10 to 15% of RCC and gather a heterogeneous population with no specific systemic treatment. Pathological classification by Elbe divides pRCC population in two morphologically different subtypes. Type 1 consists of predominantly basophilic cells, whereas type 2 contains mostly eosinophilic cells. Type 1 architecture corresponds with a single line of cells along the papillary axis, whereas type 2 generally exhibits several cell strata on the axis. Furthermore, type 2 cells demonstrate more aggressive characteristics, such as the presence of nucleoli and increased nuclear size. The papillary cores often contain edema fluid, foamy macrophages, and psammoma bodies. Further clinical reports identified that type I tumors are more likely to present as numerous, bilateral , indolent, low grade pRCC, whereas type II are associated with higher grade and poor prognosis related to metastatic evolution. The goal of this study wad to characterize each sample in order to get an idea of the genomic profile in pRCC type 2 (pRCCII).
Project description:Based on fuzzy logic selection and classification algorithms, our selection method measures the contribution of each gene for each of two pre-defined classes in order to find the best discrimination. This algorithm extracts and ranks the most pertinent markers, since it is based on feature weighting according to optimal error rate, sensitivity and specificity. We applied the fuzzy logic selection on four breast cancer microarray databases to obtain new gene signatures based on histological grade. To validate these gene signatures, we designed probes for the selected genes on Nimblegen custom microarrays and tested them on a series of 151 consecutive invasive breast carcinomas displaying clinicopathological features similar to those observed in routine practice. 151 frozen breast cancer tumors from the tumor bank of the Claudius Regaud Institute (ICR Toulouse, France) were selected. This cohort consisted of consecutive invasive breast carcinoma patients treated at Claudius Regaud Institute between 2009 and 2011. All patients included in this cohort signed an informed consent. Clinico-pathological characteristics of the series were similar to those observed in routine clinical practice (i.e. majority of pre-menopausal patients presenting with T1c, node negative, ER+ invasive ductal carcinoma of intermediate grade).
Project description:The pathogenesis of intracranial germ cell tumors (iGCTs) is not yet fully uncovered despite exhaustive genomic analyses. By means of a genome-wide methylation analysis, we show that pure germinoma is characterized by global DNA low methylation, a unique epigenetic feature distinct from all other subtypes of iGCTs. The patterns of methylation strongly resemble that of primordial germ cells (PGC) at the migration phase, indicating the cells of origin. Unlike PGC, however, hypomethylation extends to LINE1 retrotransposon. Microdissected histologically and epigenetically distinct components of mixed-GCTs shared identical mutations in the MAPK or PI3K pathways, suggesting that the genetic alterations were likely to have occurred at the pre-implantation phase in early embryogenesis. Thus, we propose iGCTs are âZygotomaâ. Genomic DNA from the 81 GCTs were hybridized to the SurePrint G3 Human CGH 8 Ã 60 K Oligo Microarrays G4450A (Agilent Technologies, Santa Clara, CA).
Project description:The goal of the study was to describe and compare the genomic landscape of Glioblastoma parental tumors and PAIRED patient derived cell lines(PDCLs). This approach enables to examine and estimate the extent to which PDCLs recapitulates the genome landscape of parental tumors - which is important for experimental model validation. In addition the consistent differences between tumors and PDCL can be evaluated in order to identify the model's weak points. In the enclosed data set, copy number variation analysis for 10 pairs of Glioblastoma tumors and their paired PDCLs are given(20 samples). Complementary data on transcriptome have been deposited at ArrayExpress under accession number E-MTAB-4803 (http://www.ebi.ac.uk/arrayexpress/experiments/E-MTAB-4803).
Project description:Multiple myeloma (MM) is a malignant plasma cell tumor characterized by various chromosomal aberrations. From the aspect of epigenetics, hypomethylation of DNA repetitive elements has been considered to induce chromosomal instability. We therefore have been interested in how it is related to chromosomal aberrations in MM. To address this, methylation levels of repetitive elements (including LINE-1, Alu and Satellite-alpha) and copy number alterations were measured in clinical samples (N=85). Bisulfite-pyrosequencing (N=85) and array-based comparative genomic hybridization (N=73) were used for these measurement, respectively. As results, methylation levels of repetitive elements were linearly associated with the degree of malignancy of plasma cells. Combined with hierarchical clustering of the result of aCGH, hypomethylation of repetitive elements was well associated with frequent chromosomal deletions. In particular, methylation levels of LINE-1 was significantly higher in samples with chromosome 13 deletion than the other (36.1% vs. 44.0%, P=0.010). The number of deleted probes was significantly correlated with LINE-1 methylation levels (R=-0.531). Finally, we observed significantly poorer prognosis in the lower LINE-1 methylation group (HR=2.8, P=0.015, compared to the higher methylation group). In conclusion, DNA methylation levels of repetitive elements, especially of LINE-1, are associated with the frequency of chromosomal deletions and prognosis in MM. 67 MM samples and 6 monoclonal gammopathy of undetermined significance (MGUS) samples were analyzed, all samples were selected by CD138 sorting
Project description:Next generation sequencing is making sequence-based molecular pathology and personalised oncology viable. We selected an individual initially diagnosed with conventional, but aggressive, prostate adenocarcinoma and sequenced the genome and transcriptome from primary and metastatic tissues collected prior to hormone therapy. The histology-pathology and genomic architecture were remarkably homogeneous, yet it was possible to determine the quadrant of the prostate tumour that likely seeded the metastatic diaspora. Despite a homogenous cell type, our transcriptome analysis revealed signatures of both luminal and neuroendocrine cell types. Remarkably, the repertoire of expressed but private gene fusions, including C15orf21:MYC, recapitulated this biology while the amplification and over expression of the stem cell gene MSI2 may have contributed to the stable hybrid cellular identity. This hybrid luminal-neuroendocrine tumour appears to represent a novel and highly aggressive case of prostate cancer with unique biological features and conceivably a propensity for rapid progression to castrate-resistance. Overall, this work highlights the importance of integrated analyses of genome, exome and transcriptome sequences for basic tumour biology, sequence-based molecular pathology, and personalized oncology. 5 samples