Gene expression regulated by miR-101 in murine MLL-AF9-transduced LSK cells
Ontology highlight
ABSTRACT: miR-101 has been reported as a tumor suppressor in several types of cancer. However, its role in AML is still unknown. In this study, we restored the expression of miR-101 in MLL-AF9 transduced LSK cells by introducing a retroviral miR-101 expression vector. To identify miR-101-regulated gene expression, we performed genome-wide gene expression analysis on GFP+ MLL-AF9-transduced LSK cells overexpressing miR-101 versus control vector. Our gene expression analysis and subsequent functional studies demonstrate that enforced expression of miR-101 has antitumor effects on the development of MLL-rearranged AML. Each group has 3 samples.
Project description:HOXA9 and MEIS1 are essential downstream effectors of the MLL-AF9 oncoprotein during leukemia induction. Leukemia derived from MLL-AF9-transduced LSK cells has a more aggressive phenotype than that derived from HOXA9/MEIS1-transduced LSK cells. To determine differential miRNA expression that contributes to increased aggressiveness in MLL-AF9-induced leukemia, miRCURY LNA microRNA Array was performed on LSK cells transduced with MLL-AF9 versus HOXA/MEIS1 oncogenes.
Project description:HOXA9 and MEIS1 are essential downstream effectors of the MLL-AF9 oncoprotein during leukaemia induction. Leukaemia derived from MLL-AF9-transduced LSK cells has a more aggressive phenotype than that derived from HOXA9/MEIS1-transduced LSK cells. To determine differential gene expression that contributes to increased aggressiveness in MLL-AF9-induced leukaemia, microarray was performed on LSK cells transduced with MLL-AF9 versus HOXA/MEIS1 oncogenes.
Project description:The pathways by which oncogenes, such as MLL-AF9, initiate transformation and leukemia in humans and mice are incompletely defined. In a study of target cells and oncogene dosage, we found that Mll-AF9, when under endogenous regulatory control, efficiently transformed LSK (Lin- Sca1+ c-kit+) stem cells while committed granulocyte-monocyte progenitors (GMPs) were transformation-resistant and did not cause leukemia. Mll-AF9 was expressed at higher levels in hematopoietic stem (HSC) than GMP cells. Mll- AF9 gene dosage effects were directly shown in experiments where GMPs were efficiently transformed by the high dosage of Mll-AF9 resulting from retroviral transduction. Mll-AF9 up-regulated expression of 196 genes in both LSK and progenitor cells, but to higher levels in LSKs than in committed myeloid progenitors. Keywords: mutant hematopoietic cells
Project description:The pathways by which oncogenes, such as MLL-AF9, initiate transformation and leukemia in humans and mice are incompletely defined. In a study of target cells and oncogene dosage, we found that Mll-AF9, when under endogenous regulatory control, efficiently transformed LSK (Lin- Sca1+ c-kit+) stem cells while committed granulocyte-monocyte progenitors (GMPs) were transformation-resistant and did not cause leukemia. Mll-AF9 was expressed at higher levels in hematopoietic stem (HSC) than GMP cells. Mll- AF9 gene dosage effects were directly shown in experiments where GMPs were efficiently transformed by the high dosage of Mll-AF9 resulting from retroviral transduction. Mll-AF9 up-regulated expression of 196 genes in both LSK and progenitor cells, but to higher levels in LSKs than in committed myeloid progenitors. Experiment Overall Design: Comparison of gene expression profiles among four types of hematopoietic cells (GMP, CMP, CLP and HSC), FACS sorted from wild type and Mll-AF9 knock-in mice. The goal was to identify genes differentially expressed in each Mll-AF9 cell type compared to the corresponding wild type cells.
Project description:To identify such targets of leukemia-related miRNAs such as miR-196b, we conducted Affymetrix gene arrays of leukemic BM samples from 24 mice including 9 primary (including 3 each of negative control, MLL-AF9, and miR-196b+MLL-AF9) and 15 secondary (including 3 negative control, 6 MLL-AF9, and 6 miR-196b+MLL-AF9) recipient mice
Project description:To identify such targets of leukemia-related miRNAs such as miR-196b, we conducted Affymetrix gene arrays of leukemic BM samples from 24 mice including 9 primary (including 3 each of negative control, MLL-AF9, and miR-196b+MLL-AF9) and 15 secondary (including 3 negative control, 6 MLL-AF9, and 6 miR-196b+MLL-AF9) recipient mice A total of 24 mouse bone marrow samples including 9 primary (including 3 each of negative control, MLL-AF9, and miR-196b+MLL-AF9) and 15 secondary (including 3 negative control, 6 MLL-AF9, and 6 miR-196b+MLL-AF9) obtained from the in vivo mouse bone marrow reconstitution assays were analyzed by use of Affymetrix GeneChip Mouse Gene 1.0 ST Array (Affymetirx, Santa Clara, CA)
Project description:We investigated the role of the transcriptional regulator Id2 in the context of MLL-rearranged acute myeloid leukemia (AML). Using an AML mouse model driven by tet-regulated MLL-AF9 co-expressed with oncogenic NRASG12D (Tet-off MLL-AF9), we demonstrated that MLL-AF9 regulates the E protein pathway by suppressing Id2, while activating the expression of its target E2-2. Moreover, we found that Id2 over-expression in Tet-Off MLL-AF9 AML cells in vitro partially phenocopies MLL-AF9 depletion and results inhibition of leukemia growth, loss of leukemia stem cell-associated gene expression pattern and induction of differentiation. To compare gene expression changes associated with enforced Id2 expression and MLL-AF9 withdrawal, RNA sequencing analysis was performed on Tet-off MLL-AF9 cells transduced with an Id2 over-expressing or a control vector, or upon MLL-AF9 dox-inducible knock-down. Primary AMLs driven by Tet-off inducible MLL/AF9 expression linked to dsRED reporter, in association with oncogenic NRASG12D (Tet-off MLL-AF9) were generated by reconstituting lethally irradiated congenic mice with foetal liver cells co-transduced with a Tet-Off-MLL-AF9-dRED retroviral vector and a second vector co-expressing NRASG12D together with the Tet-Off responsive transcriptional activator. RNA sequencing analysis sequencing analysis was performed on Tet-Off MLL-AF9/dsRED+ AML cells treated in vitro with doxycycline (DOX) for 4 days to inactivate MLL-AF9 expression or left untreated (UT). For the Id2 over-expression experiment, Tet-Off MLL-AF9/dsRED+ AML cells were transduced in vitro with an Id2-GFP or a control-GFP retroviral vector. Viable GFP-positive cells were FACS-sorted 2 days after transduction and used for RNA sequencing analysis.
Project description:This study report that miR-150, a key hematopoietic regulatory microRNA (miRNA) and one of the most downregulated miRNAs in MLL-associated leukemias, acts as a tumor suppressor to block the leukemogenic potency of leukemic stem cells. When expression of miR-150 was restored, a significantly suppressed leukemic stem cell potency of MLL-AF9 cells was observed both in vivo and in vitro. To investigate the tumor suppressive function of miR-150 in MLL-AF9 cells, we isolated three batches of MLL-AF9 cells infected with MDH empty vector or MDH-miR-150 expression retrovirus. Total RNA were extracted and applied for Agilent array analysis. Gene profiling analysis demonstrated that elevated miR-150 altered various aspects of gene expression patterns in MLL-AF9 cells, including stem cell signatures, cancer pathways, and cell survival. miR-150-MLL-AF9 and MDH-MLL-AF9 isolated cells were compared for gene expression patterns. Triplicates using three batches of FACS sorted cells were compared in pairs on the array. MDH-MLL-AF9 samples were labeld with Cy3 and miR-150-MLL-AF9 samples were labled with Cy5.
Project description:We investigated the role of the transcriptional regulators Id2 and E2-2 (encoded by Tcf4) in the context of MLL-rearranged acute myeloid leukemia (AML). Using an AML mouse model driven by a Tet-off inducible MLL-AF9 allele co-expressed with oncogenic NRASG12D, we demonstrated that MLL-AF9 regulates the E protein pathway by suppressing Id2, while activating the expression of its target E2-2. Moreover, we found that Id2 over-expression in MLL-AF9 AML cells results inhibition of leukemia growth, loss of leukemia stem cell-associated gene expression pattern and induction of differentiation. E2-2 silencing phenocopies Id2 overexpression in MLL-AF9-AML cells. To study the gene expression changes associated with E2-2 depletion in the context of MLL-rearranged AML, RNA sequencing analysis was performed on MLL-AF9;NRAS AML cells transduced with vectors expressing hairpins against E2-2 (shTcf4#654 and shTcf4#3646) or a control hairpin against Renilla luciferase (shRen). Primary AMLs driven by MLL/AF9 expression linked to cherry reporter, in association with oncogenic NRASG12D (MLL/AF9;NRAS) were generated by reconstituting lethally irradiated congenic mice with fetal liver cells co-transduced with the MSCV-MLL/AF9-IRES-cherry retroviral vector and a second vector co-expressing NRASG12D together with luciferase (MSCV-luciferase-IRES-NRASG12D). RNA sequencing analysis sequencing analysis was performed on MLL-AF9;NRAS AML cells transduced in vitro with vectors expressing hairpins against E2-2 (shTcf4#654 and shTcf4#3646) or a control hairpin against Renilla luciferase (shRen) linked to the reporter GFP. Viable GFP-positive cells were FACS-sorted 2 days after transduction and used for RNA sequencing analysis. Two independent biological replicates of the experiment were used for the RNA sequencing (9-5-14 and 14-4-14).