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Wong JJL, Ritchie W, Ebner OA, Selbach M, Wong JWH, Huang Y, Gao D, Pinello N, Gonzalez M, Baidya K, Thoeng A, Khoo TL, Bailey CG, Holst J, Rasko JEJ. Orchestrated intron retention regulates normal granulocyte differentiation. Cell 2013; 154:583-95. [PMID: 23911323 DOI: 10.1016/j.cell.2013.06.052] [Citation(s) in RCA: 334] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 05/01/2013] [Accepted: 06/28/2013] [Indexed: 12/11/2022]
Abstract
Intron retention (IR) is widely recognized as a consequence of mis-splicing that leads to failed excision of intronic sequences from pre-messenger RNAs. Our bioinformatic analyses of transcriptomic and proteomic data of normal white blood cell differentiation reveal IR as a physiological mechanism of gene expression control. IR regulates the expression of 86 functionally related genes, including those that determine the nuclear shape that is unique to granulocytes. Retention of introns in specific genes is associated with downregulation of splicing factors and higher GC content. IR, conserved between human and mouse, led to reduced mRNA and protein levels by triggering the nonsense-mediated decay (NMD) pathway. In contrast to the prevalent view that NMD is limited to mRNAs encoding aberrant proteins, our data establish that IR coupled with NMD is a conserved mechanism in normal granulopoiesis. Physiological IR may provide an energetically favorable level of dynamic gene expression control prior to sustained gene translation.
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Affiliation(s)
- Justin J-L Wong
- Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown 2050, Australia
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Pratt-Hyatt M, Lickteig AJ, Klaassen CD. Tissue distribution, ontogeny, and chemical induction of aldo-keto reductases in mice. Drug Metab Dispos 2013; 41:1480-7. [PMID: 23660342 DOI: 10.1124/dmd.113.051904] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Aldo-keto reductases (Akrs) are a conserved group of NADPH-dependent oxido-reductase enzymes. This study provides a comprehensive examination of the tissue distribution of the 16 substrate-metabolizing Akrs in mice, their expression during development, and whether they are altered by chemicals that activate distinct transcriptional factor pathways. Akr1c6, 1c14, 1c20, and 1c22 are primarily present in liver; Akr1a4, 1c18, 1c21, and 7a5 in kidney; Akr1d1 in liver and kidney; Akr1b7 in small intestine; Akr1b3 and Akr1e1 in brain; Akr1b8 in testes; Akr1c14 in ovaries; and Akrs1c12, 1c13, and 1c19 are expressed in numerous tissues. Liver expression of Akr1d1 and Akr1c is lowest during prenatal and postnatal development. However, by 20 days of age, liver Akr1d1 increases 120-fold, and Akr1c mRNAs increase as much as 5-fold (Akr1c19) to 1000-fold (Akr1c6). Treatment of mice with chemical activators of transcription factors constitutive androgen receptor (CAR), pregnane X receptor (PXR), and the nuclear factor-erythroid-2 (Nrf2) transcription factor alters liver mRNAs of Akrs. Specifically, CAR activation by 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene (TCPOBOP) increases mRNAs of Akr1b7, Akr1c6, Akr1c19, and Akr1d1, whereas PXR activation by 5-pregnenolone-16α-carbonitrile (PCN) increases the mRNA of Akr1b7 and suppresses mRNAs of Akr1c13 and Akr1c20. The Nrf2 activator 2-cyano-3,12-dioxooleana-1,9-dien-28-imidazolide (CDDO-Im) induces mRNAs of Akr1c6 and Akr1c19. Moreover, Nrf2-null and Nrf2 overexpressing mice demonstrate that this induction is Nrf2-dependent.
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Affiliation(s)
- Matthew Pratt-Hyatt
- Department of Internal Medicine, University of Kansas Medical Center, 1000 Hixon, MS 1063, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA
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Barski OA, Tipparaju SM, Bhatnagar A. The aldo-keto reductase superfamily and its role in drug metabolism and detoxification. Drug Metab Rev 2008; 40:553-624. [PMID: 18949601 PMCID: PMC2663408 DOI: 10.1080/03602530802431439] [Citation(s) in RCA: 368] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The aldo-keto reductase (AKR) superfamily comprises enzymes that catalyze redox transformations involved in biosynthesis, intermediary metabolism, and detoxification. Substrates of AKRs include glucose, steroids, glycosylation end-products, lipid peroxidation products, and environmental pollutants. These proteins adopt a (beta/alpha)(8) barrel structural motif interrupted by a number of extraneous loops and helixes that vary between proteins and bring structural identity to individual families. The human AKR family differs from the rodent families. Due to their broad substrate specificity, AKRs play an important role in the phase II detoxification of a large number of pharmaceuticals, drugs, and xenobiotics.
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Affiliation(s)
- Oleg A Barski
- Division of Cardiology, Department of Medicine, Institute of Molecular Cardiology, University of Louisville, Louisville, Kentucky 40202, USA.
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Dao MA, Creer MH, Nolta JA, Verfaillie CM. Biology of umbilical cord blood progenitors in bone marrow niches. Blood 2007; 110:74-81. [PMID: 17371947 PMCID: PMC1896129 DOI: 10.1182/blood-2006-08-034447] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Within the bone marrow (BM), hematopoietic progenitor cells (HPCs) are localized in poorly oxygenated niches where they interact with the surrounding osteoblasts (OBs) through VLA4/VCAM-1 engagement, and are exposed to interleukin-6 (IL-6), stem cell factor (SCF), and chemokines such as CXCL12 (OB factors). Umbilical cord (UC) is more highly oxygenated that the BM microenvironment. When UC-HPCs are exposed to the 2% to 3% O(2) concentration found in the bone endosteum, their survival is significantly decreased. However, engagement of VLA-4 integrins on UCB-derived CD34(+) cells reduced cell death in 2% to 3% O(2) conditions, which was associated with an increase in phospho-Ser473 AKT and an increase in phospho-Ser9 GSK3b. Consistent with the role of GSK3b in destabilizing beta-catenin, there was more cytoplasmic beta-catenin in UC-HPCs exposed to 2% to 3% O(2) on fibronectin, compared with suspension culture. UC-HPCs cultured at 2% to 3% O(2) with OB factors showed an increase in nuclear beta-catenin and persistence of a small pool of CD34(+)38(-) HPCs. CFU assays followed by surface phenotyping of the plated colonies showed improved maintenance of mixed lineage colonies with both erythroid and megakaryocytic precursors. These studies provide a biologic perspective for how UC-derived HPCs adapt to the bone endosteum, which is low in oxygen and densely populated by osteoblasts.
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Affiliation(s)
- Mo A Dao
- Stem Cell Institute, University of Minnesota Medical School, Minneapolis, USA
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Gudmundsson KO, Thorsteinsson L, Sigurjonsson OE, Keller JR, Olafsson K, Egeland T, Gudmundsson S, Rafnar T. Gene expression analysis of hematopoietic progenitor cells identifies Dlg7 as a potential stem cell gene. Stem Cells 2007; 25:1498-506. [PMID: 17322106 DOI: 10.1634/stemcells.2005-0479] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Inducible hematopoietic stem/progenitor cell lines represent a model for studying genes involved in self-renewal and differentiation. Here, gene expression was studied in the inducible human CD34+ acute myelogenous leukemia cell line KG1 using oligonucleotide arrays and suppression subtractive cloning. Using this approach, we identified Dlg7, the homolog of the Drosophila Dlg1 tumor suppressor gene, as downregulated at the early stages of KG1 differentiation. Similarly, Dlg7 was expressed in normal purified umbilical cord blood CD34+CD38- progenitors but not in the more committed CD34+CD38+ population. Dlg7 expression was not detected in differentiated cells obtained from hematopoietic colonies, nor was expression detected in purified T-cells, B-cells, and monocytes. When analyzed in different types of stem cells, Dlg7 expression was detected in purified human bone marrow-derived CD133+ progenitor cells, human mesenchymal stem cells, and mouse embryonic stem (ES) cells. Overexpression of Dlg7 in mouse ES cells increased their growth rate and reduced the number of EBs emerging upon differentiation. In addition, the EBs were significantly smaller, indicating an inhibition in differentiation. This inhibition was further supported by higher expression of Bmp4, Oct4, Rex1, and Nanog in EBs overexpressing Dlg7 and lower expression of Brachyury. Finally, the Dlg7 protein was detected in liver and colon carcinoma tumors but not in normal adjacent tissues, suggesting a role for the gene in carcinogenesis. In conclusion, our results suggest that Dlg7 has a role in stem cell survival, in maintaining stem cell properties, and in carcinogenesis. Disclosure of potential conflicts of interest is found at the end of this article.
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Affiliation(s)
- Kristbjorn Orri Gudmundsson
- Cancer and Developmental Biology Laboratory, Center for Cancer Research, National Cancer Institute-Frederick, Maryland, USA.
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Endo S, Matsumoto K, Matsunaga T, Ishikura S, Tajima K, El-Kabbani O, Hara A. Substrate specificity of a mouse aldo-keto reductase (AKR1C12). Biol Pharm Bull 2007; 29:2488-92. [PMID: 17142987 DOI: 10.1248/bpb.29.2488] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
AKR1C12, a mouse member of the aldo-keto reductase (AKR) superfamily, is highly expressed in the stomach and is identical to a protein encoded in an interleukin-3-regulated gene in mouse myeloid cells, but its function remains unknown. In this study, the recombinant AKR1C12 was purified to homogeneity and the specificity for coenzymes and substrates was examined at a physiological pH of 7.4. The enzyme reduced various alpha-dicarbonyl compounds, several ketosteroids, aldehydes and some ketones using NADH as the preferred coenzyme. In the reverse reaction, the enzyme showed coenzyme preference for NAD+, and oxidized 3alpha-, 17beta- and 20alpha-hydroxysteroids, and non-steroidal aliphatic and alicyclic alcohols, of which many hydroxysteroids and geranylgeraniol were good substrates, exhibiting low Km and high kcat/Km values. The results, together with the intracellular high ratio of NAD+/NADH, suggest that AKR1C12 functions as a dehydrogenase for the endogenous hydroxysteroids and geranylgeraniol in mouse stomach and myeloid cells.
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Affiliation(s)
- Satoshi Endo
- Laboratory of Biochemistry, Gifu Pharmaceutical University, Japan, and Hospital for Sick Children, Toronto, Ontario, Canada
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Zimmerman Z, Jones M, Shatry A, Komatsu M, Mammolenti M, Levy R. Cytolytic pathways used by effector cells derived from recipient naive and memory T cells and natural killer cells in resistance to allogeneic hematopoietic cell transplantation. Biol Blood Marrow Transplant 2006; 11:957-71. [PMID: 16338617 DOI: 10.1016/j.bbmt.2005.07.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2005] [Accepted: 07/11/2005] [Indexed: 11/23/2022]
Affiliation(s)
- Zachary Zimmerman
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, Florida 33101, USA
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Matsunaga T, Shintani S, Hara A. Multiplicity of mammalian reductases for xenobiotic carbonyl compounds. Drug Metab Pharmacokinet 2006; 21:1-18. [PMID: 16547389 DOI: 10.2133/dmpk.21.1] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A variety of carbonyl compounds are present in foods, environmental pollutants, and drugs. These xenobiotic carbonyl compounds are metabolized into the corresponding alcohols by many mammalian NAD(P)H-dependent reductases, which belong to the short-chain dehydrogenase/reductase (SDR) and aldo-keto reductase superfamilies. Recent genomic analysis, cDNA isolation and characterization of the recombinant enzymes suggested that, in humans, the six members of each of the two superfamilies, i.e., total of 12 enzymes, are involved in the reductive metabolism of xenobiotic carbonyl compounds. They comprise three types of carbonyl reductase, dehydrogenase/reductase (SDR family) member 4, 11beta-hydroxysteroid dehydrogenase type 1, L-xylulose reductase, two types of aflatoxin B1 aldehyde reductase, 20alpha-hydroxysteroid dehydrogenase, and three types of 3alpha-hydroxysteroid dehydrogenase. Accumulating data on the human enzymes provide new insights into their roles in cellular and molecular reactions including xenobiotic metabolism. On the other hand, mice and rats lack the gene for a protein corresponding to human 3alpha-hydroxysteroid dehydrogenase type 3, but instead possess additional five or six genes encoding proteins that are structurally related to human hydroxysteroid dehydrogenases. Characterization of the additional enzymes suggested their involvement in species-specific biological events and species differences in the metabolism of xenobiotic carbonyl compounds.
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Nalbant D, Youn H, Nalbant SI, Sharma S, Cobos E, Beale EG, Du Y, Williams SC. FAM20: an evolutionarily conserved family of secreted proteins expressed in hematopoietic cells. BMC Genomics 2005; 6:11. [PMID: 15676076 PMCID: PMC548683 DOI: 10.1186/1471-2164-6-11] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2004] [Accepted: 01/27/2005] [Indexed: 12/04/2022] Open
Abstract
Background Hematopoiesis is a complex developmental process controlled by a large number of factors that regulate stem cell renewal, lineage commitment and differentiation. Secreted proteins, including the hematopoietic growth factors, play critical roles in these processes and have important biological and clinical significance. We have employed representational difference analysis to identify genes that are differentially expressed during experimentally induced myeloid differentiation in the murine EML hematopoietic stem cell line. Results One identified clone encoded a previously unidentified protein of 541 amino acids that contains an amino terminal signal sequence but no other characterized domains. This protein is a member of family of related proteins that has been named family with sequence similarity 20 (FAM20) with three members (FAM20A, FAM20B and FAM20C) in mammals. Evolutionary comparisons revealed the existence of a single FAM20 gene in the simple vertebrate Ciona intestinalis and the invertebrate worm Caenorhabditis elegans and two genes in two insect species, Drosophila melanogaster and Anopheles gambiae. Six FAM20 family members were identified in the genome of the pufferfish, Fugu rubripes and five members in the zebrafish, Danio rerio. The mouse Fam20a protein was ectopically expressed in a mammalian cell line and found to be a bona fide secreted protein and efficient secretion was dependent on the integrity of the signal sequence. Expression analysis revealed that the Fam20a gene was indeed differentially expressed during hematopoietic differentiation and that the other two family members (Fam20b and Fam20c) were also expressed during hematcpoiesis but that their mRNA levels did not vary significantly. Likewise FAM20A was expressed in more limited set of human tissues than the other two family members. Conclusions The FAM20 family represents a new family of secreted proteins with potential functions in regulating differentiation and function of hematopoietic and other tissues. The Fam20a mRNA was only expressed during early stages of hematopoietic development and may play a role in lineage commitment or proliferation. The expansion in gene number in different species suggests that the family has evolved as a result of several gene duplication events that have occurred in both vertebrates and invertebrates.
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Affiliation(s)
- Demet Nalbant
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
| | - Hyewon Youn
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
- Southwest Cancer Center at University Medical Center, Lubbock, Texas 79430, USA
| | - S Isil Nalbant
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
| | - Savitha Sharma
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
| | - Everardo Cobos
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
- Southwest Cancer Center at University Medical Center, Lubbock, Texas 79430, USA
| | - Elmus G Beale
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
| | - Yang Du
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
| | - Simon C Williams
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
- Southwest Cancer Center at University Medical Center, Lubbock, Texas 79430, USA
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Vergnes L, Phan J, Stolz A, Reue K. A cluster of eight hydroxysteroid dehydrogenase genes belonging to the aldo-keto reductase supergene family on mouse chromosome 13. J Lipid Res 2003; 44:503-11. [PMID: 12562828 DOI: 10.1194/jlr.m200399-jlr200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A subclass of hydroxysteroid dehydrogenases (HSD) are NADP(H)-dependent oxidoreductases that belong to the aldo-keto reductase (AKR) superfamily. They are involved in prereceptor or intracrine steroid modulation, and also act as bile acid-binding proteins. The HSD family members characterized thus far in human and rat have a high degree of protein sequence similarity but exhibit distinct substrate specificity. Here we report the identification of nine murine AKR genes in a cluster on chromosome 13 by a combination of molecular cloning and in silico analysis of this region. These include four previously isolated mouse HSD genes (Akr1c18, Akr1c6, Akr1c12, Akr1c13), the more distantly related Akr1e1, and four novel HSD genes. These genes exhibit highly conserved exon/intron organization and protein sequence predictions indicate 75% amino acid similarity. The previously identified AKR protein active site residues are invariant among all nine proteins, but differences are observed in regions that have been implicated in determining substrate specificity. Differences also occur in tissue expression patterns, with expression of some genes restricted to specific tissues and others expressed at high levels in multiple tissues. Our findings dramatically expand the repertoire of AKR genes and identify unrecognized family members with potential roles in the regulation of steroid metabolism.
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Affiliation(s)
- Laurent Vergnes
- Department of Human Genetics and Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
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Du Y, Campbell JL, Nalbant D, Youn H, Bass ACH, Cobos E, Tsai S, Keller JR, Williams SC. Mapping gene expression patterns during myeloid differentiation using the EML hematopoietic progenitor cell line. Exp Hematol 2002; 30:649-58. [PMID: 12135661 DOI: 10.1016/s0301-472x(02)00817-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE The detailed examination of the molecular events that control the early stages of myeloid differentiation has been hampered by the relative scarcity of hematopoietic stem cells and the lack of suitable cell line models. In this study, we examined the expression of several myeloid and nonmyeloid genes in the murine EML hematopoietic stem cell line. METHODS Expression patterns for 19 different genes were examined by Northern blotting and RT-PCR in RNA samples from EML, a variety of other immortalized cell lines, and purified murine hematopoietic stem cells. Representational difference analysis (RDA) was performed to identify differentially expressed genes in EML. RESULTS Expression patterns of genes encoding transcription factors (four members of the C/EBP family, GATA-1, GATA-2, PU.1, CBFbeta, SCL, and c-myb) in EML were examined and were consistent with the proposed functions of these proteins in hematopoietic differentiation. Expression levels of three markers of terminal myeloid differentiation (neutrophil elastase, proteinase 3, and Mac-1) were highest in EML cells at the later stages of differentiation. In a search for genes that were differentially expressed in EML cells during myeloid differentiation, six cDNAs were isolated. These included three known genes (lysozyme, histidine decarboxylase, and tryptophan hydroxylase) and three novel genes. CONCLUSION Expression patterns of known genes in differentiating EML cells accurately reflected their expected expression patterns based on previous studies. The identification of three novel genes, two of which encode proteins that may act as regulators of hematopoietic differentiation, suggests that EML is a useful model system for the molecular analysis of hematopoietic differentiation.
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Affiliation(s)
- Yang Du
- Department of Cell Biology & Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
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Sykes DB, Kamps MP. Estrogen-dependent E2a/Pbx1 myeloid cell lines exhibit conditional differentiation that can be arrested by other leukemic oncoproteins. Blood 2001; 98:2308-18. [PMID: 11588024 DOI: 10.1182/blood.v98.8.2308] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The molecular pathways of normal myeloid differentiation, as well as the mechanisms by which oncogenes disrupt this process, remain poorly understood. A major limitation in approaching this problem has been the lack of suitable cell lines that exhibit normal, terminal, and synchronous differentiation in the absence of endogenous oncoproteins and in response to physiologic cytokines, and whose differentiation can be arrested by ectopically expressed human oncoproteins. This report describes clonal, granulocyte-macrophage colony-stimulating factor-dependent myeloid cell lines that exhibit these properties. The cell lines were established by conditional immortalization of primary murine marrow progenitors with an estrogen-regulated E2a/Pbx1-estrogen receptor fusion protein. Clones were identified that proliferated as immortalized blasts in the presence of estrogen, and that exhibited granulocytic, monocytic, or bipotential (granulocytic and monocytic) differentiation on estrogen withdrawal. Differentiation was normal and terminal as evidenced by morphology, cell surface markers, gene expression, and functional assays. The differentiation of the cells could be arrested by heterologous oncoproteins including AML1/ETO, PML/RARalpha, PLZF/RARalpha, Nup98/HoxA9, and other Hox proteins. Furthermore, the study examined the effects of cooperating oncoproteins such as Ras or Bcr/Abl, which allowed for both factor-independent proliferation and differentiation, or Bcl-2, which permitted factor-independent survival but not proliferation. These myeloid cell lines provide tools for examining the biochemical and genetic pathways that accompany normal differentiation as well as a system in which to dissect how other leukemic oncoproteins interfere with these pathways.
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Affiliation(s)
- D B Sykes
- Department of Molecular Pathology, University of California San Diego School of Medicine, La Jolla 92093-0612, USA.
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