Project description:Searching for new strategies of acute myeloid leukemia (AML) treatment is of particular interest. Cell lines, e. g. HL-60 and NB4, represent model systems to study molecular features of leukemic cells. The all-trans-retinoic acid (ATRA) has proven itself to be an effective treatment for one of AML subtypes, i.e., acute promyelocytic leukemia (APL). At the same time, ATRA causes granulocytic differentiation of non-APL leukemic cells in vitro. Combination of new therapeutics with ATRA could improve efficiency of treatment. Studying the proteome perturbation in leukemic cells under the ATRA treatment allows to determine potential regulatory molecules that could be affected pharmacologically. Thus, the TMT-based proteomic profiles of HL-60, NB4, and K562 cell lines under the ATRA treatment were obtained at 0, 3, 12, 24, and 72 h after the ATRA treatment.
Project description:Treatment of acute promyelocytic leukemia (APL) with all-trans-retinoic acid (ATRA) results in terminal differentiation of leukemic cells toward neutrophil granulocytes. Administration of ATRA leads to massive changes in gene expression, including down-regulation of cell proliferation-related genes and induction of genes involved in immune function. One of the most induced genes in APL NB4 cells is transglutaminase 2 (TG2). RNAi-mediated stable silencing of TG2 in NB4 cells (TG2-KD NB4) coupled with whole genome microarray analysis revealed that TG2 is involved in the expression of a large number of ATRA-regulated genes. The affected genes participate in granulocyte functions and their silencing lead to reduced adhesive, migratory and phagocytic capacity of neutrophils and less superoxide production. The expression of genes related to cell cycle control also changed, suggesting that TG2 regulates myeloid cell differentiation. CC chemokines CCL2, 3, 22, 24 and cytokines IL1B and IL8 involved in the development of differentiation syndrome (DS) are expressed at significantly lower levels in TG2-KD NB4 cells than in wild-type NB4 cells upon ATRA treatment. Based on our results, we propose that reduced expression of TG2 in differentiating APL cells may suppress effector functions of neutrophil granulocytes and attenuate the ATRA-induced inflammatory phenotype of DS. We used microarrays to detail the global program of gene expression underlying ATRA-induced differentiation of TG2 knockout NB4 cells. TG2 knockout NB4 cells were differentiated for 48 and 72 hours in the presence of ATRA and their gene expression profiles were compared to the wild-type cells at the same time points. Undifferentiated wild-type and TG2 knockout NB4 cells were used as untreated controls. Three biological replicates each.
Project description:Chromatin accessibility is a key determinant of cell-type-specific gene expression. Here, we have investigated the chromatin architecture of different acute myeloid leukemia (AML) cells and the changes in accessibility when NB4 (APL) cells undergo the process of differentiation. For nuclease-accessible site sequencing (NA-seq; Gargiulo et al. 2009), chromatin-accessible libraries were generated in different AML leukemic cells by using restriction enzymes NlaIII and HpaII. In the case of NB4 cells, accessibility was mapped both before and after treatment with all-trans retinoic acid (ATRA) for 48hr. Differences were observed between the two conditions, and chromatin accessibility was correlated with underlying epigenetic modifications. For validation purposes, NA-seq libraries (using the NlaIII enzyme) were generated in APL and AML M1 patient's blasts. All of the ChIP-seq (Martens et al. 2010) studies were performed in leukemic NB4 and SKNO-1 cells. Supplementary file 'GSE30254_All_accessibleregions_ATRA_NB4_fseq.wig' includes data for Samples GSM749512, GSM749513, GSM749516, and GSM749517. Supplementary file 'GSE30254_All_accessibleregions_untreated_NB4_fseq.wig' includes data for Samples GSM749510, GSM749511, GSM749514, and GSM749515.
Project description:Treatment of acute promyelocytic leukemia (APL) with all-trans-retinoic acid (ATRA) results in terminal differentiation of leukemic cells toward neutrophil granulocytes. Administration of ATRA leads to massive changes in gene expression, including down-regulation of cell proliferation-related genes and induction of genes involved in immune function. One of the most induced genes in APL NB4 cells is transglutaminase 2 (TG2). RNAi-mediated stable silencing of TG2 in NB4 cells (TG2-KD NB4) coupled with whole genome microarray analysis revealed that TG2 is involved in the expression of a large number of ATRA-regulated genes. The affected genes participate in granulocyte functions and their silencing lead to reduced adhesive, migratory and phagocytic capacity of neutrophils and less superoxide production. The expression of genes related to cell cycle control also changed, suggesting that TG2 regulates myeloid cell differentiation. CC chemokines CCL2, 3, 22, 24 and cytokines IL1B and IL8 involved in the development of differentiation syndrome (DS) are expressed at significantly lower levels in TG2-KD NB4 cells than in wild-type NB4 cells upon ATRA treatment. Based on our results, we propose that reduced expression of TG2 in differentiating APL cells may suppress effector functions of neutrophil granulocytes and attenuate the ATRA-induced inflammatory phenotype of DS.
Project description:We report the use of RNAseq to determine genomewide transcriptional changes induced by all-trans retinoic acid differentiation of NB4 acute promyelocytic leukemia (APL) cells.
Project description:Epigenetic abnormalities are frequently involved in the initiation and progression of cancers including acute myeloid leukemia (AML). A subtype of AML, Acute promyelocytic leukemia (APL), is mainly driven by a specific oncogenic fusion event of PML-RARα. PML-RARα was reported as a transcription repressor through the interaction with NCoR/HDAC complexes leading to the mis-suppression of its target genes and differentiation blockage. While previous studies were mainly focused on the connection of histone acetylation, it is still largely unknown whether alternative epigenetics mechanisms are involved in APL progression. KDM5A is a demethylase of histone H3 lysine 4 di- and tri- methylations (H3K4me2/3) and a transcription corepressor. Here, we found that the loss of KDM5A led to APL NB4 cell differentiation and retarded growth. Mechanistically, through epigenomics and transcriptomics analyses, we detected KDM5A binding in 1,889 genes, with the majority of the binding events at promoter regions. KDM5A suppressed the expression of 621 genes, including 42 PML-RARα target genes primarily by controlling the H3K4me2 in the promoters and 5’ end intragenic regions. In addition, a recently reported pan-KDM5 inhibitor, CPI-455 on its own could phenocopy the differentiation effects as KDM5A loss in NB4 cells. CPI-455 treatment or KDM5A knockout could greatly sensitize NB4 cells to ATRA induced differentiation. Our findings indicated that KDM5A contributed to the differentiation blockage in the APL cell line NB4, and inhibition of KDM5A could greatly potentiate NB4 differentiation.
Project description:About 5-10% newly diagnosed and about 20-30% of relapsed acute promyelocytic leukemia (APL) patients will have disease recurrence after receiving currently accepted standards of care. While there are reports of micro-environment mediated drug resistance (EM-DR) in AML, there is no data on the effect of malignant promyelocyte and stromal interaction on Arsenic trioxide (ATO) induced apoptosis. We undertook a preliminary study to evaluate the role of EM-DR to ATO in APL. In direct co-culture (contact dependent system) of malignant promyelocyte with stromal cells, the stromal cells gave a significant protective effect against ATO at different concentrations used (1 to 8 μmol; NB4 (APL cell line) In a gene expression profiling comparing NB4 cells in co-culture with NB4 cells alone, 1846 genes were differentially regulated. On a preliminary analysis, we observed an up-regulation of various pathways such as adhesion (ITGB1, ITGB2, ITGB7, etc.), Cytokines (IL-6, IL-8, IL-18, CCL2, CCL10, etc.) Wnt signalling (Wnt5a, Wnt11, NFATC4, etc,) NF-kB pathway (ICAM1, BIRC2, BIRC3, XIAP1, etc.) in the leukemic cells. The NF-kB pathway has been validated using real time PCR which correlated with the genes being differentially regulated in NB4 cells co-cultured in stroma. Agilent one-color experiment,Organism: Homo sapiens ,Custom Agilent 8x60k Human Whole Genome Microarray Gene expression (AMADID: 039494) , Labeling kit: Agilent Quick-Amp labeling Kit (p/n5190-0442)
Project description:About 5-10% newly diagnosed and about 20-30% of relapsed acute promyelocytic leukemia (APL) patients will have disease recurrence after receiving currently accepted standards of care. While there are reports of micro-environment mediated drug resistance (EM-DR) in AML, there is no data on the effect of malignant promyelocyte and stromal interaction on Arsenic trioxide (ATO) induced apoptosis. We undertook a preliminary study to evaluate the role of EM-DR to ATO in APL. In direct co-culture (contact dependent system) of malignant promyelocyte with stromal cells, the stromal cells gave a significant protective effect against ATO at different concentrations used (1 to 8 μmol; NB4 (APL cell line) In a gene expression profiling comparing NB4 cells in co-culture with NB4 cells alone, 1846 genes were differentially regulated. On a preliminary analysis, we observed an up-regulation of various pathways such as adhesion (ITGB1, ITGB2, ITGB7, etc.), Cytokines (IL-6, IL-8, IL-18, CCL2, CCL10, etc.) Wnt signalling (Wnt5a, Wnt11, NFATC4, etc,) NF-kB pathway (ICAM1, BIRC2, BIRC3, XIAP1, etc.) in the leukemic cells. The NF-kB pathway has been validated using real time PCR which correlated with the genes being differentially regulated in NB4 cells co-cultured in stroma.