Project description:RUNX1 and ETV6-RUNX1 possess the same DNA-binding runt domain and are therefore expected to bind to canonical RUNX motifs. As the ETV6-RUNX1 fusion arises in the context of native RUNX1 expression, and since RUNX1 is retained or amplified in B-ALL, the two proteins are likely to compete for the same target sites. To assess this, we performed RUNX1 ChIP-seq in the presence of exogenous ETV6-RUNX1 (or non DNA binding ETV6-RUNX1-R139G) and the reciprocal experiment: ETV6-RUNX1 ChIP (using a V5 tag) in the presence of exogenous RUNX1 or vector control.
Project description:ETV6-RUNX1 is a fusion protein bringing together almost the entire coding sequence of RUNX1, including the DNA binding runt domain, and the N-terminus of ETV6 which is known to include transcriptional repressors including histone deacetylation 3 (HDAC3). Here we perform ChIP-seq for the active chromatin mark H3K27ac in the NALM6 B-cell acute lymphoblastic leukaemia cell line expressing ETV6-RUNX1 or mutant derivatives of ETV6-RUNX1: Delta helix-loop-helix (dHLH) is a deletion of the pointed domain; R139G is a point mutation in the runt DNA-binding domain.
Project description:This SuperSeries is composed of the following subset Series: GSE25102: Illumina SNP-array data for 2 ETV6/RUNX1-positive Acute Lymphoblastic Leukemia samples and corresponding normal samples GSE25116: Affymetrix SNP-array data for 2 ETV6/RUNX1-positive Acute Lymphoblastic Leukemia samples and corresponding normal samples Refer to individual Series
Project description:The ETV6/RUNX1 fusion gene, present in 25% of B-lineage childhood acute lymphoblastic leukemia (ALL), is thought to represent an initiating event, which requires additional genetic changes for leukemia development. To identify additional genetic alterations, 24 ETV6/RUNX1-positive ALLs were analyzed using 500K single nucleotide polymorphism arrays. The results were combined with previously published data sets, allowing us to ascertain genomic copy number aberrations (CNAs) in 164 cases. In total, 45 recurrent CNAs were identified with an average number of 3.5 recurrent changes per case (range 0-13). Twenty-six percent of cases displayed a set of recurrent CNAs identical to that of other cases in the data set. The majority (74%), however, displayed a unique pattern of recurrent CNAs, indicating a large heterogeneity within this ALL subtype. As previously demonstrated, alterations targeting genes involved in B-cell development were common (present in 28% of cases). However, the combined analysis also identified alterations affecting nuclear hormone response (24%) to be a characteristic feature of ETV6/RUNX1-positive ALL. Studying the correlation pattern of the CNAs allowed us to highlight significant positive and negative correlations between specific aberrations. Furthermore, oncogenetic tree models identified ETV6, CDKN2A/B, PAX5, del(6q), and +16 as possible early events in the leukemogenic process. Affymetrix SNP arrays were performed according to the manufacturer's directions on DNA extracted from 23 leukemic bone marrow samples and one ETV6/RUNX1-positive cell line.
Project description:ETV6-RUNX1 is a first-hit mutation in childhood B cell precursor acute lymphoblastic leukaemia. ETV6-RUNX1 is a fusion protein which inherits the DNA-binding runt domain from RUNX1. Here we performed chromatin precipitation for native RUNX1 and ETV6-RUNX1 using RUNX1 antibodies and specifically for the ETV6-RUNX1 fusion using a V5-tag pull down.
Project description:Overwhelming evidence indicates that long non-coding RNAs have essential roles in tumorigenesis. Nevertheless, their expression and role in pediatric B-cell precursor acute lymphoblastic leukemia has not been extensively explored. Here, we conducted a comprehensive analysis of the long non-coding RNA transcriptome in ETV6/RUNX1 positive BCP-ALL, one of the most frequent subtypes of pediatric leukemia. An ETV6/RUNX1 expression signature was established, consisting of 596 lncRNAs (434 up and 162 down) using expression analysis of a series of primary patient samples. Subsequently, RNA sequencing from BCP-ALL cell lines and shRNA-mediated silencing of ETV6/RUNX1, illustrated that lnc-NKX2-3-1, lnc-TIMM21-5, lnc-ASTN1-1 and lnc-RTN4R-1 are bona fide ETV6/RUNX1 targets and could serve as novel biomarkers of this prevalent subtype of human leukemia.
Project description:Acute lymphoblastic leukemia (ALL), the most common malignant disorder in childhood, is typically associated with numerical chromosomal aberrations, fusion genes or small focal deletions, thought to represent important pathogenetic events in the development of the leukemia. Mutations, such as single nucleotide changes, have also been reported in childhood ALL, but these have only been studied by sequencing a small number of candidate genes. Herein, we report the first unbiased sequencing of the whole exome of two cases of pediatric ALL carrying the ETV6/RUNX1 (TEL/AML1) fusion gene (the most common genetic subtype) and corresponding normal samples. A total of 14 somatic mutations were identified, including four and seven protein-altering nucleotide substitutions in each ALL. Twelve mutations (86%) occurred in genes previously described to be mutated in other types of cancer, but none was found to be recurrent in an extended series of 29 ETV6/RUNX1-positive ALLs. The number of single nucleotide mutations was similar to the number of copy number alterations as detected by single nucleotide polymorphism arrays. Although the true pathogenetic significance of the mutations must await future functional evaluations, this study provides a first estimate of the mutational burden at the genetic level of t(12;21)-positive childhood ALL. Affymetrix SNP arrays were performed according to the manufacturer's directions on DNA extracted from 2 leukemic bone marrow samples and two corresponding normal blood samples.
Project description:Analysis of gene signatures in WT+Ctrl vs WT+ETV6-RUNX1, Btg1-/- and Btg1-/-+ETV6-RUNX1 in cKit+Ter119- fetal liver-derived hematopoietic progenitor cells (FL-HPCs). The Btg1-/-+ETV6-RUNX1 FL-HPCs display a strong increase in proliferation compared to WT+ETV6-RUNX1. Total RNA otained from WT+Ctrl, WT+ETV6-RUNX1, Btg1-/-+Ctrl and Btg1-/-+ETV6-RUNX1 FL-HPCs cells that were cultured for 12 days in expansion medium.
Project description:Genome binding/occupancy profiling of ETS Variant Transcription Factor 6- Runt Related Transcription Factor 1 fusion protein (ETV6-RUNX1) in REH cells by high throughput sequencing. ETV6-RUNX1 is expressed in pediatric t(12;21) ETV6-RUNX1 B cell precursor acute lymphoblastic leukemia.
Project description:Acute lymphoblastic leukemia (ALL), the most common malignant disorder in childhood, is typically associated with numerical chromosomal aberrations, fusion genes or small focal deletions, thought to represent important pathogenetic events in the development of the leukemia. Mutations, such as single nucleotide changes, have also been reported in childhood ALL, but these have only been studied by sequencing a small number of candidate genes. Herein, we report the first unbiased sequencing of the whole exome of two cases of pediatric ALL carrying the ETV6/RUNX1 (TEL/AML1) fusion gene (the most common genetic subtype) and corresponding normal samples. A total of 14 somatic mutations were identified, including four and seven protein-altering nucleotide substitutions in each ALL. Twelve mutations (86%) occurred in genes previously described to be mutated in other types of cancer, but none was found to be recurrent in an extended series of 29 ETV6/RUNX1-positive ALLs. The number of single nucleotide mutations was similar to the number of copy number alterations as detected by single nucleotide polymorphism arrays. Although the true pathogenetic significance of the mutations must await future functional evaluations, this study provides a first estimate of the mutational burden at the genetic level of t(12;21)-positive childhood ALL. Illumina SNP-array genotyping was performed according to the manufacturer's directions on DNA extracted from 2 leukemic bone marrow samples and two corresponding normal blood samples. The genotype data from the arrays were used for quality assesment of genotype data from high throughput sequencing.