MiRNA profiling of the MV4-11 cell line treated with trabectidin or azacitidin
ABSTRACT: In order to study the effects of trabectedin in chronic myelomonocytic leukemia and in juvenile myelomonocytic leukemia, we performed whole genome transcriptional profiling of a model cell line treated under either the reference drug for CMML / JMML (Azacitidine) or trabectedin.
Project description:In order to study the effects of trabectedin in chronic myelomonocytic leukemia and in juvenile myelomonocytic leukemia, we performed whole genome transcriptional profiling of a model cell line treated under either the reference drug for CMML / JMML (Azacitidine) or trabectedin.
Project description:Ras mutations are commonly observed in Juvenile Myelomonocytic Leukemia (JMML) and Chronic Myelomonocytic Leukemia (CMML). JMML and CMML transform into Acute Myeloid Leukemia (AML) in about 10% and 50% of patients respectively. However, how additional events cooperate with Ras to promote this transformation are largely unknown. We show that absence of the Ubiquitin-Specific-peptidase 22 (USP22), a component of the SAGA chromatin-remodeling complex linked to cancer progression, unexpectedly promotes AML transformation in mice expressing oncogenic KrasG12D/+. USP22 deficiency in KrasG12D/+ mice resulted in shorter survival compared to control mice. This was due to a block in myeloid cell differentiation leading to the generation of AML. This effect was cell autonomous since mice transplanted with USP22-deficient KrasG12D/+ cells developed an aggressive disease and died rapidly. The transcriptome profile of USP22-deficient KrasG12D/+ progenitors resembled leukemic stem cells and was highly correlated with genes associated with poor prognosis in AML. We show that USP22 functions as a PU.1 deubiquitylase by positively regulating its protein stability and promoting the expression of PU.1 target genes. Reconstitution of PU.1 overexpression in USP22-deficient KrasG12D/+ progenitors rescued their differentiation. Our findings uncovered an unexpected role for USP22 in Ras-induced leukemogenesis and provide further insights into the function of USP22 in carcinogenesis. Overall design: mRNA expression profile of myeloid progenitors (cKit_Linlow/-) from 7-9 weeks old Kras-Usp22WT and Kras-Usp22KO mice
Project description:In order to assess the potential difference on the effect of lurbinectedin on monocytes compared to trabectedin, which has a selective killing effect (Germano et al., 2013), we performed a whole transcriptome assay on monocytes from healthy donors stimulated with LPS and with either trabectedin or lurbinectedin. Doxorubicin, an unrelated drug, was used as an internal control.
Project description:RNA-seq of bone marrow CD34+ cells of myelodysplastic syndrome (MDS) and chronic myelomonocytic leukemia (CMML) patients to identify at the molecular pathways involved in primary resistance to AZA therapy. Overall design: RNA-seq of bone marrow CD34+ cells of MDS and CMML patients at pre-treatment and after 6 cycles of AZA treatment to identify at the molecular pathways involved in resistance to AZA therapy.
Project description:Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic disorder with heterogeneous clinical, morphological and genetic characteristics. Clonal cytogenetic abnormalities are found in 20-30% of patients with CMML. Patients with low risk cytogenetic features (normal karyotype and isolated loss of Y chromosome) account for approximately 80% of CMML patients and often fall into the low risk categories of CMML prognostic scores. SNP-A were performed in 82 CMML patients with low risk karyotypes and uninformative results for conventional G-banding cytogenetics (CC). Overall design: Affymetrix SNP arrays were performed according to the manufacturer's directions on DNA extracted from bone marrow or peripheral blood samples. Copy number analysis of Affymetrix array was performed for 82 CMML samples at diagnosis or prior to any treatment,
Project description:The purpose of experiments consisted in studying the mode of action of Trabectedin in Desmoplastic Small Round Cell Tumor (DSRCT). In order to investigate the effects of Trabectedin in the expression of EWS-WT1 target genes in relation to the drug growth inhibitory effect, the JN-DSCRT-1 cell line was treated for 1 hour with 5 nM of Trabectedin. Samples were collected at 6, 12 and 24 hours after drug washout. Three biological replicates were used for each time point.
Project description:To elucidate the mechanisms behind the high sensitivity of myxoid/round cell liposarcoma (MRCL) to trabectedin and the suggested selectivity for specific subtypes we have developed and characterized two MRCL xenografts differing for the breakpoint of the fusion gene FUS- HOP, respectively of type II and III. Transcription profiling experiments were carried out after trabectidin treatment in four separate time points (control, 24h after the first dose, 24h after the third dose, and 15 days after the third dose) for both types of xenografts in order to identify genes and pathways involved with the mechanisms of action of trabectedin in MRCL.
Project description:Chronic myelomonocytic leukemia (CMML) has recently been associated with a high incidence of diverse mutations in genes implicated in epigenetic mechanisms such as TET2 or EZH2. We have performed genome-wide methylation arrays and mutational analysis of TET2, IDH1, IDH2, EZH2 and JAK2 in a group of 24 patients with CMML. 249 genes were differentially methylated between CMML patients and controls. Using Ingenuity pathway analysis enrichment in a gene network centered in PLC, JNK and ERK, a recently described pathway involved in CMML was found, suggesting the potential role of epigenetics in the regulation of these pathways. Mutations of TET2, JAK2 and EZH2 were found in 15 patients (65.2%), 4 patients (16.6%) and 1 patient (4.1%) respectively while no mutations in the IDH1 and IDH2 genes were identified. Interestingly, patients with wild type TET2 clustered separately from patients with TET2 mutations, showed a higher degree of hypermethylation and were associated with the presence of altered karyotypes a known prognostic factor in CMML. Our results demonstrate the presence of aberrant DNA methylation in CMML and identifies TET2 mutant CMML as a biologically distinct disease subtype with a different epigenetic profile. 24 samples of CMML patients, 4 healthy donor Peripheral Blood samples and 4 healthy donor Bone Marror samples
Project description:Juvenile myelomonocytic leukemia (JMML) is a very rare and aggressive stem cell disease that mainly occurs in young children. RAS activation constitutes the core component of oncogenic signaling. In addition, the leukemic blasts of a quarter of JMML patients present with monosomy 7 (-7), whereas more than half of the patients show enhanced age-adjusted fetal hemoglobin (HbF) levels. Hematopoietic stem cell transplantation is the current standard of care. This results in an event-free survival of 50 - 60%, indicating that novel molecular driven therapeutic options are urgently needed. Using gene expression profiling in an extensive series of 82 patient samples, we aimed at understanding the molecular biology behind JMML and identified a previously unrecognized molecular subgroup characterized by high LIN28B expression. Interestingly, LIN28B overexpression was significantly correlated with higher HbF levels whereas patients with -7 seldom showed enhanced LIN28B expression. In line with LIN28B’s role as mediator of fetal hematopoiesis, this explains the biology behind the observation that patients with -7 are rarely diagnosed with high age-adjusted HbF levels. In addition, this new fetal-like JMML subgroup presented with reduced levels of most members of the let-7 microRNA family and showed characteristic overexpression of genes involved in fetal hematopoiesis and stem cell self-renewal. Finally, high LIN28B expression was associated with poor clinical outcome in our JMML patient series, but not independent from other prognostic factors such as age and age-adjusted HbF levels. In conclusion, we identified LIN28B as a crucial molecular player at the heart of a novel fetal-like subgroup in JMML. Overall design: miRNA expression was measured on a qPCR-based platform in 21 JMML patients and 4 healthy donors in the discovery cohort. Corresponding mRNA and lncRNA expression data were measured on Agilent. All patient data can be found in Supplementary Table S1.
Project description:Chromosomal abnormalities are detected in 20-30% of patients with chronic myelomonocytic leukemia (CMML) and correlate with prognosis. Epigenetic abnormalities are frequent in CMML, including mutations in DNA methylation and histone-modifying enzymes, but the methylation profile is not well characterized in these patients. In this study we performed DNA methylation microarrays in 65 CMML patients and 10 healthy controls. Differential methylation analysis between patients and controls allowed us to identify abnormalities in DNA methylation including hypermethylated genes, large genome regions with aberrant DNA methylation and altered cellular pathways. Hierarchical cluster analysis identified two main clusters that associated with the clinical, biological and genetic features of patients. Group 1 was enriched in patients that presented with adverse clinical and biological characteristics and that had a poorer overall survival and progression free survival. In addition, significant differences in DNA methylation was observed between patients with low risk and intermediate/high risk karyotypes and between TET2 mutant and wild-type patients. These results demonstrate that DNA methylation is altered in CMML and is associated with distinct biological and clinical features. Furthermore, these results may provide a useful basis for identifying new therapeutic targets. Overall design: DNA methylation profiles of bone marrow from CMML patients and CD34+ enriched blood from healthy controls.