Project description:Chronic myeloid leukemia (CML) is a hematopoetic stem cell disease with distinct biological and clinical features. The biological foundation of the stereotypical progression from chronic phase through accelerated phase to blast crisis is poorly understood. We used DNA microarrays to compare gene expression in 91 cases of CML in chronic (42 cases), accelerated (17 cases), and blast phases (32 cases). Three thousand genes were found to be significantly (p<10-10) associated with the progression from chronic to blast phase. A comparison of the gene signatures of chronic, accelerated, and blast phases suggest that the progression of chronic phase CML from chronic advanced phase (accelerated and blast crisis) CML is a two-step rather than a three-step process, with new gene expression changes occurring early in accelerated phase before the accumulation of increased leukemia blast cells. The genetic signature of advanced phase CML is similar to that of normal CD34+ cells; however, progression also involved novel genes not expressed in normal CD34+ cells. Especially noteworthy is deregulation of the WNT/b-catenin pathway, the decreased expression of both JunB and Fos, and dysregulation of genes under the control of MZF1 and delta EF1 zinc finger transcription factors. Studies of CML patients who relapsed after initially successful treatment with imatinib mesylate demonstrated a gene expression pattern closely related to advanced phase disease. Take together, these data suggest that CML progression begins relative early and before clinical and pathological detection, and features distinct genetic differences compared to normal hematpoetic cells that might provide diagnostic and therapeutic targets. Keywords: disease state analysis
Project description:This study compares the epigenetic signatures of CD34+ cells from chronic phase chronic myeloid leukemia (CML) samples and blast phase CML samples v.s. normal CD34+ cells from cord blood and adult bone marrow samples. H3K27me3 genomic loci were detected by ChIP-seq.
Project description:Chronic myeloid leukemia (CML) is a biphasic clonal hematopoietic stem cell disorder driven by the Philadelphia chromosome (Ph)-encoded BCR::ABL1 oncogene. The blast phase (BP) in CML progressed from indolent chronic phase (CP), usually has a dismal outcome. Single-cell RNA sequencing (scRNA-seq) have identified the pretreatment features linked to therapy resistance and disease progression. We performed the scRNA-seq on bone marrow cells derived from paired CML-CP and CML-BLBC samples, and found that CD24 displayed a striking upregulation in CML-BLBC samples when compared with both the CML-CP and Ph+ B-ALL samples, suggesting the potential as a target in the future therapy of patients with CML-BLBC. Therefore, we profiled the BM samples from patients with CML-CP (n = 16), CML-BLBC (n = 8), and de novo Ph+ B-ALL (n = 13) using bulk RNA sequencing to validate the upregulated expressio of CD24 in patients with CML-BLBC.
Project description:Copy number and LOH analysis was performed for 56 chronic myeloid leukemia cases obtained from 23 CML cases obtained atchronic phase, accelerated phase, blast crisis, or remission. All caseswere genotyped with Affymetrix 250k Sty and Nsp arrays. Keywords: Acute leukemia, BCR-ABL1, chronic myeloid leukemia, copy number analysis, loss-of-heterozygosity, genomics *** Due to privacy concerns, the primary SNP array data is no longer available with unrestricted access. Individuals wishing to obtain this data for research purposes may request access using the Web links below. ***
Project description:Chronic myeloid leukemia (CML) is a hematopoetic stem cell disease with distinct biological and clinical features. The biological foundation of the stereotypical progression from chronic phase through accelerated phase to blast crisis is poorly understood. We used DNA microarrays to compare gene expression in 91 cases of CML in chronic (42 cases), accelerated (17 cases), and blast phases (32 cases). Three thousand genes were found to be significantly (p<10-10) associated with the progression from chronic to blast phase. A comparison of the gene signatures of chronic, accelerated, and blast phases suggest that the progression of chronic phase CML from chronic advanced phase (accelerated and blast crisis) CML is a two-step rather than a three-step process, with new gene expression changes occurring early in accelerated phase before the accumulation of increased leukemia blast cells. The genetic signature of advanced phase CML is similar to that of normal CD34+ cells; however, progression also involved novel genes not expressed in normal CD34+ cells. Especially noteworthy is deregulation of the WNT/b-catenin pathway, the decreased expression of both JunB and Fos, and dysregulation of genes under the control of MZF1 and delta EF1 zinc finger transcription factors. Studies of CML patients who relapsed after initially successful treatment with imatinib mesylate demonstrated a gene expression pattern closely related to advanced phase disease. Take together, these data suggest that CML progression begins relative early and before clinical and pathological detection, and features distinct genetic differences compared to normal hematpoetic cells that might provide diagnostic and therapeutic targets. Samples from different phases of CML were hybridized against the pool of chronic phases of samples.
Project description:BCR-ABL1 lymphoblastic leukaemia is characterized by the deletion of Ikaros. The Philadelphia chromosome, encoding BCR-ABL1, is the defining lesion of chronic myelogenous leukemia (CML) and a subset of acute lymphoblastic leukemia (ALL) cases. To define oncogenic lesions that cooperate with BCR-ABL1 to induce ALL, we performed genome-wide analysis of leukemic samples from 23 CML cases and 304 ALL cases, including 43 BCR-ABL1 B-ALL cases. IKZF1 (encoding the transcription factor Ikaros) was deleted in 83.7% of BCR-ABL1 B-ALL cases, but not in chronic phase CML. Deletion of IKZF1 was also identified as an acquired lesion in lymphoid blast crisis of CML. The IKZF1 deletions resulted in haploinsufficiency, expression of a dominant negative Ikaros isoform or the complete loss of Ikaros expression. Sequencing of IKZF1 deletion breakpoints suggested that aberrant V(D)J recombination is responsible for the deletions. These findings suggest that genetic lesions resulting in the loss of Ikaros function are a key event in the development of BCR-ABL1 ALL. *** Due to privacy concerns, the primary SNP array data is no longer available with unrestricted access. Individuals wishing to obtain this data for research purposes may request access using the Web links below. *** This SuperSeries is composed of the SubSeries listed below.
Project description:Little is known about the impact of DNA methylation on the evolution/progression of chronic myeloid leukemia (CML). We investigated the methylome of CML patients in chronic phase (CP-CML), accelerated phase (AP-CML) and blast crisis (BC-CML) as well as in controls by reduced representation bisulfite sequencing. While only ~600 differentially methylated CpG sites were identified in samples obtained from CP-CML patients compared to controls, ~6,500 differentially methylated CpG sites were found in cells from BC-CML patients. In the majority of affected CpG sites methylation was increased. In CP-CML patients who progressed to AP-CML/BC-CML, we identified up to 897 genes which were methylated at the time of progression but not at the time of diagnosis. Using RNA-sequencing, we observed downregulated expression of many of these genes in BC-CML compared to CP-CML-derived cells. Several of them are well-known tumor suppressor genes or regulators of cell proliferation. 5-aza-2 -deoxycytidine treatment of CML cells resulted in gene re-expression and in a dose-dependent cell growth reduction. Single nucleotide variants of certain epigenetic modifiers during CML progression were not found. Together, our results demonstrate that methylation changes occur frequently during CML progression and may provide a useful basis for revealing new targets of therapy in advanced CML.
Project description:Profiling CD34+ BCR-ABL+ cells of CML patients in chronic phase or blast crisis to identify differentially expressed stage-specific genes.
Project description:Title: Gene expression analysis of indolent and aggressive forms of Chronic Myeloid Leukaemia (CML). Description: Chronic Myeloid Leukaemia presents in chronic phase (CP) and terminates in 'blast crisis'. Despite a common abnormality, the duration of CP is variable. The aim is to compare the gene expression profiles of the indolent and aggressive forms of CML. All samples were taken within 3 months of first diagnosis. Indolent patients were defined by chronic phase CML, duration minimum 7 years. Aggressive patients were defined by chronic phase, duration maximum 3 years.
Project description:While Chronic Myelogenous Leukemia (CML) is generally well controlled with Imatinib and other kinase inhibitors, blast crisis CML (bcCML) continues to be resistant to current therapies and remains highly lethal. Here we report a genome-wide in vivo CRISPR screen to better define the biological determinants of bcCML establishment and propagation in a physiologic context. This screen identified a large number of new genes and programs critically required for bcCML including those essential for chromatin remodeling, spliceosomal assembly, PLK1 and Myc signaling.