Project description:Wide inter-individual variation in terms of outcome and toxic side effects of treatment exist among patients with AML receiving chemotherapy with cytarabine (Ara-C) and daunorubicin (Dnr). Drug resistance and relapse are considered major causes of treatment failure. Gene expression profiling was undertaken to address possible mechanisms of Ara-C/Dnr resistance. Based on ex vivo Ara-C cytotoxicity at diagnosis, Ara-C sensitive (IC50 <3uM AraC) and Dnr sensitive samples (IC50 < 0.5 uM) (5 samples each) were included for microarray analysis. These were compared with the samples which were drug resistant ex vivo at diagnosis. Our microarray experiment resulted in indentifying differentially expressed genes under ex vivo Ara-C sensitive as well as Dnr sensitive samples compared to ex vivo Drug resistant samples.
Project description:Wide inter-individual variation in terms of outcome and toxic side effects of treatment exist among patients with AML receiving chemotherapy with cytarabine (Ara-C) and daunorubicin (Dnr). Drug resistance and relapse are considered major causes of treatment failure. Gene expression profiling was undertaken to address possible mechanisms of Ara-C/Dnr resistance. Based on ex vivo Ara-C cytotoxicity at diagnosis, Ara-C sensitive (IC50 <3uM AraC) and Dnr sensitive samples (IC50 < 0.5 uM) (5 samples each) were included for microarray analysis. These were compared with the samples which were drug resistant ex vivo at diagnosis. Our microarray experiment resulted in indentifying differentially expressed genes under ex vivo Ara-C sensitive as well as Dnr sensitive samples compared to ex vivo Drug resistant samples. One-color experiment,Organism: Homo sapiens, Custom Human Whole Genome 8x60k Array designed by Genotypic Technology Private Limited (AMADID: 27114), Labeling kit: Agilent Quick-Amp labeling Kit (p/n5190-0442)
Project description:The Acute Myeloid Leukemia cell line HL-60 was rendered resistant to daunorubicin (DNR) or cytarabine (Ara-C) by continuous exposure to the drug up to concentrations of 30nM for DNR and 100nM for Ara-C. Transcriptomic analysis were then performed by RNA-Seq to compare the cell lines
Project description:Daunorubicin (DNR) and Cytarabin (Ara-C) are the main chemotherapeutic drugs used for Acute Myeloid Leukemias (AML) treatment. However, their mode of action is not well understood. To decipher if these drug would induce rapid transcriptional reprogramming, we treated HL-60 AML cell line with DNR or Ara-C for 3 hours and carried out a transcriptomic analyses. In addition, we had shown that Reactive Oxigen Species (ROS) produced by NADPH oxidases (NOX) are involved in DNR-induced gene expression. We therefore also performed a transcriptomic analyses in HL-60 cells treated with DNR and VAS2870, an NADPH oxidase inhibitor. HL-60 cells were treated or not for 3 hours with 2 µM Ara-C, 1 µM DNR or 1 µM DNR + 20µM VAS 2870. RNAs were purified from 3 independent experiments and used to probe Affymetrix Human Gene 2.0 ST Genechips
Project description:Apoptosis is deregulated in most, if not all, cancers, including hematological malignancies. In this study, we wanted to test whether primary acute myeloid leukemia (AML) samples are sensitive for inhibitor of apoptosis (IAP) protein antagonist treatment in vitro, and which AML subgroup might profit most from such a novel therapeutic strategy. We treated diagnostic samples of 67 adult AML patients with either cytarabine (ara-C) or IAP antagonist BV6 and correlated sensitivity with clinical, cytogenetic and molecular markers, and expression levels of selected genes involved in apoptosis. Primary AML samples showed differential sensitivity to treatment with either ara-C (40% sensitive, 17% intermediate, 43% resistant) or BV6 (51% sensitive, 21% intermediate, 28% resistant). Notably, 69% of ara-C resistant samples showed a good to fair response to IAP inhibition. Furthermore, combination treatment of ara-C with BV6 showed additive effects in most samples. Differences in sensitivity to IAP antagonist treatment correlated with significantly elevated expression levels of TNF and lower levels of XIAP in BV6 sensitive samples, as well as with NPM1 mutations. Gene expression profiling pointed to apoptosis-related pathways, which were specifically induced by IAP inhibition in sensitive samples. Thus, our results suggest IAP inhibition as a potential novel therapeutic option in AML.
Project description:Acute Myeloid Leukemia cell line HL-60 were treated with 1 M daunorubicin (DNR) or 2M cytarabin (Ara-C) or 1 M DNR + 10 M VAS2870 (NADPH oxidase inhibitor) for 2 hours. ChIP-Seq experiments were carried out with SUMO-2/3 antibodies. Immunoprecipitated DNA and corresponding inputs from 3 independent experiments were pooled and processed for deep-sequencing (Hi-SEq 2000, Illumina).
Project description:SUMOylation, a post-translational modification of the ubiquitin family plays key roles in Acute Myeloid Leukemias response to therapies, in particular through the regulation of gene expression. We have investigated here how daunorubicine (DNR) and cytarabine (Ara-C), the two main drugs used for Acute Myeloid Leukemia treatment, affect the distribution of SUMO on chromatin in the HL-60 cell lines. We found that DNR but not Ara-C leads to a massive decrease in the presence of SUMOylated proteins on the chromatin, in particular at promoters and enhancers, where they are enriched.
Project description:Genome wide DNA methylation profiling of AML patient samples treated with PBS or DAC. The Illumina Infinium 450 Human DNA methylation was used to examine the methylation profile of 8 patient samples and 2 cell lines. Genome wide DNA methylation profiling of AML xenografts treated with either PBS control or with decitacine (DAC) alone, cytarabine (Ara-C) alone, DAC and Ara-C together (D+A), DAC followed by Ara-C (D/A) or with Ara-C followed by DAC (A/D).
Project description:Genotoxicants have been used for decades as front-line therapies against cancer on the basis of their DNA-damaging actions. However, some of their non-DNA-damaging effects are also instrumental for killing dividing cells. We report here that the anthracycline Daunorubicin (DNR) but not the nucleoside analog Cytarabine, the two main drugs used to treat Acute Myeloid Leukemia (AML), induces rapid (3 hours) and broad transcriptional changes in AML cells. The regulated genes are particularly enriched in genes controlling cell proliferation and death, as well as inflammation and immunity. These transcriptional changes are preceded by DNR-dependent deSUMOylation of chromatin proteins, in particular at active promoters and enhancers. Surprisingly, accelerating deSUMOylation dampens DNR-induced transcriptional reprogramming. Quantitative proteomics shows that proteins that are deSUMOylated in response to DNR are mostly transcription factors, transcriptional co-regulators and chromatin organizers. Among them, the CCCTC-binding factor CTCF is highly enriched at SUMO-binding sites found in cis-regulatory regions. This is notably the case at the promoter of the DNR-induced NFKB2 gene. Although DNR does not modify CTCF binding on chromatin in general and at NFKB2 promoter in particular, it leads to a SUMO-dependent reconfiguration of chromatin loops engaging CTCF- and SUMO-bound NFKB2 promoter with distal cis-regulatory regions.
Project description:Our CRISPR-based pharmacogenomic screening identified the E3 ubiquitin ligase Herc1 as a key modulator of sensitivity to cytarabine (Ara-C) chemotherapy in the MLL/AF9 (MA) mouse AML model both in vitro and in vivo. To identify the intracellular proteins whose abundance is modulated by Herc1, we performed comparative LC-MS3 analysis of in vitro-cultured MA mouse AML cells that were transduced with either a small-guide RNA targeting Herc1 (i.e., CRISPR-mediated Herc1-knockout) or a control non-targeting small-guide RNA, at steady state or after brief exposure to Ara-C (200 nMol for 6 hours).