title: Isolation and characterisation of Kasumi-1 human myeloid leukaemia cell line resistant to tumour necrosis factor alpha-induced apoptosis.
abstract: Tumour necrosis factor (TNF)-alpha induces apoptosis in a human acute myeloid leukaemia cell line, Kasumi-1. To examine the role of protein phosphorylation in signal transduction of TNF-alpha-induced apoptosis, a variant cell line resistant to TNF-alpha was established by an intermittent challenge of Kasumi-1 cells with increasing concentrations of TNF-alpha for 6 months. The mechanism of resistance to TNF-alpha appears to be in the post-receptor pathway because expression of p55 TNF receptor in the variant cells is increased compared with that of the parental Kasumi-1 cells. In renaturation assays, TNF-alpha induced a rapid activation of different protein kinases of different molecular weights, including the 50 kDa protein kinase (PK50) followed by the 35 kDa protein kinase (PK35), in the parental Kasumi-1 cells. The dose-response of TNF-alpha required to activate PK50 and PK35 was closely related to concentrations of TNF-alpha that induced apoptosis. Treatment of Kasumi-1 cells with ceramide also activated PK35. In TNF-resistant variant cells, activation of PK35 in response to TNF-alpha or ceramide was practically nil. These findings suggest that activation of PK35 through the ceramide pathway may play an important role in signal transduction of TNF-alpha in the Kasumi-1 cell line, while the decreased activation of PK35 may explain the insensitivity of the variant cells towards TNF-alpha.
authors.affiliation: Department of Molecular Pathobiology, Mie University School of Medicine, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Ido
authors.forename: K
authors.initials: K
authors.lastname: Hayashi
authors.forename: S
authors.initials: S
authors.lastname: Kato
authors.forename: H
authors.initials: H
authors.lastname: Ogawa
authors.forename: Y
authors.initials: Y
authors.lastname: Komada
authors.forename: Y W
authors.initials: YW
authors.lastname: Zhau
authors.forename: X L
authors.initials: XL
authors.lastname: Zhang
authors.forename: M
authors.initials: M
authors.lastname: Sakurai
authors.forename: K
authors.initials: K
authors.lastname: Suzuki
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D004351:Drug Resistance; D004789:Enzyme Activation; D006801:Humans; D007951:Leukemia, Myeloid / Q000473:pathology*; D011494:Protein Kinases / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D015398:Signal Transduction; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D014409:Tumor Necrosis Factor-alpha; D011494:Protein Kinases; D011505:Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases