Distinct 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 SamplesXbp1 is a major transcription factor in the unfolded protein response. To uncover its function in DCs we generated a conditional KO for Xbp1 in dendritic cells. We here compare the expression of mRNAs in two different splenic DC subpopulations, CD8a and CD11b DCs in both WT and KO mice.
The unfolded-protein-response sensor IRE-1α regulates the function of CD8α+ dendritic cells.
Specimen part
View SamplesUsing a dataset of 54 pregnant and 113 age/stage-matched non-pregnant breast cancer patients with complete clinical and survival data; we evaluated the pattern of hot spot somatic mutations and performed transcriptomic profiling using Sequenom and Affymetrix, respectively. Breast cancer molecular subtypes were defined using PAM50 and 3-Gene classifiers. We performed Gene set enrichment analysis (GSEA) to evaluate pathways associated with diagnosis during pregnancy. We investigated the differential expression of cancer-related genes and published gene sets according to pregnancy. We finally investigated genes associated with disease-free survival.
Biology of breast cancer during pregnancy using genomic profiling.
Age, Disease stage
View SamplesAnalysis of 80 glioblastoma specimen of patients treated within clinical trials and 4 samples of "normal" brain tissue (non-tumoral). The data was used to identify factors of resistance to a chemoradiation therapy protocol of radiotherapy and concomitant and adjuvant temozolomide (alkylating agent).
Stem cell-related "self-renewal" signature and high epidermal growth factor receptor expression associated with resistance to concomitant chemoradiotherapy in glioblastoma.
Sex, Age, Specimen part, Disease, Treatment, Subject
View SamplesGEP on Affymetrix Genechip HTA 2.0 microarrays was performed on ex vivo cell-sorted GC-Tfh and pre-Tfh from TONS and FL
Human Lymphoid Stromal Cells Contribute to Polarization of Follicular T Cells Into IL-4 Secreting Cells.
Specimen part, Treatment
View SamplesGEP on Affymetrix U133+2.0 microarrays was performed on in vitro expanded stromal cells
Human Lymphoid Stromal Cells Contribute to Polarization of Follicular T Cells Into IL-4 Secreting Cells.
Specimen part
View SamplesIdentification of druggable targets is a prerequisite for developing targeted therapies against Ewing sarcoma. We report the identification of Protein Kinase C Beta (PRKCB) as a protein specifically and highly expressed in Ewing sarcoma as compared to other pediatric cancers. Its transcriptional activation is directly regulated by the EWSR1-FLI1 oncogene. Getting insights in PRKCB activity we show that, together with PRKCA, it is responsible for the phosphorylation of histone H3T6, allowing global maintenance of H3K4 trimethylation on a variety of gene promoters. In the long term, PRKCB RNA interference induces apoptosis in vitro. More importantly, in xenograft mice models, complete impairment of tumor engraftment and even tumor regression were observed upon PRKCB inhibition, highlighting PRKCB as a most valuable therapeutic target. Deciphering PRKCB roles in Ewing sarcoma using expression profiling, we found a strong overlap with genes modulated by EWSR1-FLI1 and an involvement of RPKCB in regulating crucial signaling pathways. Altogether, we show that PRKCB may have two important independent functions and should be considered as highly valuable for understanding Ewing sarcoma biology and as a promising target for new therapeutic approaches in Ewing sarcoma.
Targeting the EWSR1-FLI1 oncogene-induced protein kinase PKC-β abolishes ewing sarcoma growth.
Cell line
View SamplesDNA damage activates a complex signaling network in cells that blocks cell cycle progression, recruits factors involved in DNA repair, and/or triggers programs that control senescence or programmed cell death. Alterations in chromatin structure are known to be important for the initiation and propagation of the DNA damage response, although the molecular details are unclear. We investigated the role of chromatin structure in the DNA damage response by monitoring multiple timedependent checkpoint signaling and response events with a high-content multiplex image-based RNAi screen of chromatin modifying and interacting genes. We discovered that Brd4, a double bromodomain-containing protein, functions as an endogenous inhibitor of DNA damage signaling by binding to acetylated histones at sites of open chromatin and altering chromatin accessibility. Loss of Brd4 or disruption of acetyl-lysine binding results in an increase in both the number and size of radiation-induced !H2AX nuclear foci while overexpression of a Brd4 splice isoform completely suppresses !H2AX formation, despite equivalent double strand break formation. Brd4 knock-down cells displayed altered chromatin structure, prolonged cell cycle checkpoint arrest and enhanced survival after irradiation, while overexpression of Brd4 isoform B results in enhanced radiationinduced lethality. Brd4 is the target of the t(15;19) chromosomal translocation in a rare form of cancer, NUT Midline Carcinoma. Acetyl lysine-bromodomain interactions of the Brd4-NUT fusion protein suppresses !H2AX foci in discrete nuclear compartments, rendering cells more radiosensitive, mimicking overexpression of Brd4 isoform B. NUT Midline Carcinoma is sensitive to radiotherapy, however tumor material from this rare cancer is scarce. We therefore investigated Brd4 expression in another human cancer commonly treated with radiotherapy, glioblastoma multiforme, and found that expression of Brd4 isoform B correlated specifically with treatment response to radiotherapy. These data implicate Brd4 as an endogenous insulator of DNA damage signaling through recognition of epigenetic modifications in chromatin and suggest that expression of the Brd4 in human cancer can modulate the clinical response to DNA-damaging cancer therapy.
The bromodomain protein Brd4 insulates chromatin from DNA damage signalling.
Cell line
View SamplesWe performed array comparative genomic hybridization (aCGH) and gene expression profiling in 203 samples of diffuse large B cell lymphoma (DLBCL). By gene expression, at least three molecular subtypes of DLBCL termed as germinal center B cell-like (GCB) DLBCL, activated B cell-like (ABC) DLBCL, and primary mediastinal B cell lymphoma (PMBL) can be distinguished. Combining gene expression profiling and aCGH, revealed copy number abnormalities that had strikingly different frequencies in the three molecular DLBCL subtypes. These data provide genetic evidence that the DLBCL subtypes are distinct diseases that utilize different oncogenic pathways.
Molecular subtypes of diffuse large B-cell lymphoma arise by distinct genetic pathways.
Sex, Age, Specimen part, Disease, Disease stage, Subject
View Samples