title: Interferon-alpha enhances artemisinin-induced differentiation of HL-60 leukemia cells via a PKC alpha/ERK pathway.
abstract: Interferon-alpha (IFN-alpha) has been used in the treatment of several cancers, including chronic myeloid leukemia. Artemisinin, a sesquiterpene lactone endoperoxide that exists in several medicinal plants, is a well known anti-malarial agent. We previously reported that artemisinin by itself caused a relatively low level of HL-60 cell differentiation. In this study, we investigated the effects of IFN-alpha in combination with artemisinin on cell growth and differentiation in HL-60 leukemia cells. Combination of IFN-alpha and artemisinin synergistically induced the levels of leukemia cell differentiation, although IFN-alpha by itself did not affect cell proliferation and differentiation. The increased cell differentiation by IFN-alpha and artemisinin was significantly suppressed by the inhibitors for protein kinase C (PKC), extracellular signal-regulated kinase (ERK) and jun N-terminal kinase (JNK), but not by the inhibitors for phosphatidylinositol 3-kinase (PI3-K) and p38 mitogen-activated protein kinase (MAPK). Furthermore, co-treatment with IFN-alpha increased levels of PKC alpha and phosphorylated ERK. Taken together, these results indicate the enhancement of artemisinin-induced HL-60 cell differentiation by IFN-alpha through the activation of a PKC alpha/ERK signaling pathway, and suggest a possible use of IFN-alpha and artemisinin in the treatment of leukemic diseases.
authors.affiliation: School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: Seung Hyun
authors.initials: SH
authors.lastname: Kim
authors.forename: Sang-Young
authors.initials: SY
authors.lastname: Chun
authors.forename: Tae Sung
authors.initials: TS
authors.lastname: Kim
mesh_terms: D037621:Artemisinins / Q000494:pharmacology*; D015153:Blotting, Western; D002453:Cell Cycle / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors / Q000502:physiology*; D005455:Fluorescent Antibody Technique; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000378:metabolism; D018922:HL-60 Cells; D006801:Humans; D016898:Interferon-alpha / Q000494:pharmacology*; D048031:JNK Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D051571:Protein Kinase C-alpha / Q000037:antagonists & inhibitors / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D037621:Artemisinins; D004791:Enzyme Inhibitors; D016898:Interferon-alpha; C031327:artemisinin; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D051571:Protein Kinase C-alpha; D048049:Extracellular Signal-Regulated MAP Kinases; D048031:JNK Mitogen-Activated Protein Kinases