title: Autotaxin is expressed in FLT3-ITD positive acute myeloid leukemia and hematopoietic stem cells and promotes cell migration and proliferation.
abstract: Autotaxin (ATX) has been reported to act as a motility and growth factor in a variety of cancer cells. The ATX protein acts as a secreted lysophospholipase D by converting lysophosphatidylcholine (LPC) to lysophosphatidic acid (LPA), which signals via G-protein-coupled receptors and has important functions in cell migration and proliferation. This study demonstrates that ATX expression is specifically upregulated and functionally active in acute myeloid leukemia (AML) harboring an internal tandem duplication (ITD) mutation of the FLT3 receptor gene. Moreover, ATX expression was also found in normal human CD34+ progenitor cells and selected myeloid and lymphoid subpopulations. Enforced expression of mutant FLT3-ITD by retroviral vector transduction increased ATX mRNA in selected cell lines, whereas inhibition of FLT3-ITD signaling by sublethal doses of PKC412 or SU5614 led to a significant downregulation of ATX mRNA and protein levels. In the presence of LPC, ATX expression significantly increased proliferation. LPA induced proliferation, regardless of ATX expression, and induced chemotaxis in all tested human leukemic cell lines and human CD34(+) progenitors. LPC increased chemotaxis only in cells with high expression of endogenous ATX by at least 80%, demonstrating the autocrine action of ATX. Inhibition of ATX using a small molecule inhibitor selectively induced killing of ATX-expressing cell lines and reduced motility in these cells. Our data suggest that the production of bioactive LPA through ATX is involved in controlling proliferation and migration during hematopoiesis and that deregulation of ATX contributes to the pathogenesis of AML.
authors: Medical Department I, University Hospital Dresden, Germany.
authors: Claudia
authors: C
authors: Ortlepp
authors: Christine
authors: C
authors: Steudel
authors: Caroline
authors: C
authors: Heiderich
authors: Sina
authors: S
authors: Koch
authors: Angela
authors: A
authors: Jacobi
authors: Martin
authors: M
authors: Ryser
authors: Sebastian
authors: S
authors: Brenner
authors: Martin
authors: M
authors: Bornhäuser
authors: Benedikt
authors: B
authors: Brors
authors: Wolf-Karsten
authors: WK
authors: Hofmann
authors: Gerhard
authors: G
authors: Ehninger
authors: Christian
authors: C
authors: Thiede
mesh_terms: D000208:Acute Disease; D015153:Blotting, Western; D002460:Cell Line; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects / Q000235:genetics*; D049109:Cell Proliferation; D002478:Cells, Cultured; D020869:Gene Expression Profiling; D015973:Gene Expression Regulation, Leukemic / Q000187:drug effects; D006412:Hematopoietic Stem Cells / Q000378:metabolism*; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D020014:K562 Cells; D007951:Leukemia, Myeloid / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D008244:Lysophosphatidylcholines / Q000378:metabolism / Q000494:pharmacology; D008246:Lysophospholipids / Q000378:metabolism / Q000494:pharmacology; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D010727:Phosphoric Diester Hydrolases / Q000235:genetics* / Q000378:metabolism; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019311:Staurosporine / Q000031:analogs & derivatives / Q000494:pharmacology; D020080:Tandem Repeat Sequences / Q000235:genetics; D051941:fms-Like Tyrosine Kinase 3 / Q000235:genetics*; D000099189:Lysophospholipase D
chemical_list: D007211:Indoles; D008244:Lysophosphatidylcholines; D008246:Lysophospholipids; D010727:Phosphoric Diester Hydrolases; D047428:Protein Kinase Inhibitors; D019311:Staurosporine; D051941:fms-Like Tyrosine Kinase 3; D000099189:Lysophospholipase D; C416849:SU 5614; C497970:FLT3 protein, human; C059539:midostaurin; C032881:lysophosphatidic acid