title: Lyn and Fgr protein-tyrosine kinases prevent apoptosis during retinoic acid-induced granulocytic differentiation of HL-60 cells.
abstract: The human promyelocytic leukemia cell line HL-60 can be induced to differentiate toward neutrophils and subsequently die via apoptosis in vitro. In this paper, we investigated the roles of protein-tyrosine kinases (PTKs) in retinoic acid (RA)-induced granulocytic differentiation of HL-60 cells. Accompanying the RA-induced differentiation, activities of src family PTKs Lyn and Fgr became detected and reached a plateau 2 days after the stimulation. The immunoblotting using anti-phosphotyrosine antibody (PY-20) showed that the proteins of 56 and 53 kDa were predominantly tyrosine-phosphorylated at day 2. Adsorption and immunoprecipitation of the cell lysate by specific antibodies evidenced that these phosphotyrosine-containing proteins are Lyn and Fgr PTKs. The degree of both activities and tyrosine phosphorylation of these PTKs was reduced to be minimal at day 5 when the HL-60 cells start to die by apoptosis. The inhibitors of PTKs, herbimycin A and genistein, were demonstrated to cause premature cell death of HL-60 cells in the presence of RA. The death was the consequence of an apoptotic process. The Ra-treated HL-60 cells, when incubated with specific c-lyn or c-fgr antisense oligodeoxynucleotide, also underwent premature death at day 2. These data implicate that Lyn and Fgr PTKs prevent programmed cell death to promote granulocytic differentiation of HL-60 cells.
authors.affiliation: Institute of Biomatrix, Nippi Inc., Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Katagiri
authors.forename: K K
authors.initials: KK
authors.lastname: Yokoyama
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
authors.forename: S
authors.initials: S
authors.lastname: Omura
authors.forename: S
authors.initials: S
authors.lastname: Irie
authors.forename: T
authors.initials: T
authors.lastname: Katagiri
mesh_terms: D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D001483:Base Sequence; D002454:Cell Differentiation / Q000187:drug effects; D015870:Gene Expression; D006098:Granulocytes / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D018922:HL-60 Cells; D006801:Humans; D008969:Molecular Sequence Data; D016376:Oligonucleotides, Antisense / Q000494:pharmacology*; D010750:Phosphoproteins / Q000302:isolation & purification / Q000378:metabolism; D019000:Phosphotyrosine; D011505:Protein-Tyrosine Kinases / Q000096:biosynthesis*; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis* / Q000302:isolation & purification; D013873:Thionucleotides; D014212:Tretinoin / Q000494:pharmacology*; D019061:src-Family Kinases / Q000096:biosynthesis* / Q000302:isolation & purification
chemical_list: D016376:Oligonucleotides, Antisense; D010750:Phosphoproteins; D011518:Proto-Oncogene Proteins; D013873:Thionucleotides; D019000:Phosphotyrosine; D014212:Tretinoin; D011505:Protein-Tyrosine Kinases; C060902:lyn protein-tyrosine kinase; C053102:proto-oncogene proteins c-fgr; D019061:src-Family Kinases