title: c-kit expression by CD34+ bone marrow progenitors and inhibition of response to recombinant human interleukin-3 following exposure to c-kit antisense oligonucleotides.
abstract: The c-kit proto-oncogene encodes a receptor having tyrosine-specific kinase activity and has been mapped to chromosome 4 in the human and chromosome 5 in the mouse, at the dominant white spotting locus (W). Mutations at the W locus affect various aspects of murine hematopoiesis. The c-kit proto-oncogene has been shown to be expressed by leukemic myeloblasts, but not by normal unseparated human bone marrow cells. The role of this oncogene in differentiation and proliferation of human hematopoietic progenitors is presently undefined. To determine c-kit expression by normal hematopoietic progenitors, CD34+ cells were isolated from disease-free human bone marrow, and RNA-based polymerase chain reaction (PCR) techniques were used to assess expression. By this method, we have demonstrated c-kit expression by CD34+ bone marrow progenitors. To address the functional requirement for c-kit expression in normal human hematopoiesis, CD34+ cells were incubated in the presence of sense, antisense, or missense oligonucleotides to c-kit, and subsequently cultured in the presence of either recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) or recombinant human interleukin-3 (rhIL-3). Exposure of CD34+ cells to c-kit antisense oligonucleotides significantly inhibited colony-forming ability of cells cultured in the presence of rhIL-3, but had no effect on colony formation of cells cultured in rhGM-CSF. Together, these data suggest a possible role for c-kit in hematopoietic proliferation and differentiation that may be linked to some, but not all, stimulatory factors.
authors.affiliation: Department of Hematology/Oncology, Medical College of Virginia, Richmond 23298.
authors.forename: J P
authors.initials: JP
authors.lastname: Catlett
authors.forename: J A
authors.initials: JA
authors.lastname: Leftwich
authors.forename: E H
authors.initials: EH
authors.lastname: Westin
authors.forename: S
authors.initials: S
authors.lastname: Grant
authors.forename: T F
authors.initials: TF
authors.lastname: Huff
mesh_terms: D015703:Antigens, CD / Q000032:analysis*; D018952:Antigens, CD34; D001483:Base Sequence; D001854:Bone Marrow Cells; D002455:Cell Division; D004247:DNA / Q000737:chemistry; D005260:Female; D015870:Gene Expression; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006412:Hematopoietic Stem Cells / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D007377:Interleukin-3 / Q000494:pharmacology*; D015470:Leukemia, Myeloid, Acute / Q000473:pathology; D008297:Male; D008969:Molecular Sequence Data; D016376:Oligonucleotides, Antisense / Q000737:chemistry / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D019009:Proto-Oncogene Proteins c-kit; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D011994:Recombinant Proteins / Q000494:pharmacology; D014158:Transcription, Genetic
chemical_list: D015703:Antigens, CD; D018952:Antigens, CD34; D007377:Interleukin-3; C000715470:MAS1 protein, human; D016376:Oligonucleotides, Antisense; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins; D011994:Recombinant Proteins; D012313:RNA; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D004247:DNA; D019009:Proto-Oncogene Proteins c-kit