title: Role for protein geranylgeranylation in adult T-cell leukemia cell survival.
abstract: Adult T-cell leukemia (ATL) is a fatal lymphoproliferative disease that develops in human T-cell leukemia virus type I (HTLV-I)-infected individuals. Despite the accumulating knowledge of the molecular biology of HTLV-I-infected cells, effective therapeutic strategies remain to be established. Recent reports showed that the hydroxyl-3-methylglutaryl (HMG)-CoA reductase inhibitor statins have anti-proliferative and apoptotic effects on certain tumor cells through inhibition of protein prenylation. Here, we report that statins hinder the survival of ATL cells and induce apoptotic cell death. Inhibition of protein geranylgeranylation is responsible for these effects, since simultaneous treatment with isoprenoid precursors, geranylgeranyl pyrophosphate or farnesyl pyrophosphate, but not a cholesterol precursor squalene, restored the viability of ATL cells. Simvastatin inhibited geranylgeranylation of small GTPases Rab5B and Rac1 in ATL cells, and a geranylgeranyl transferase inhibitor GGTI-298 reduced ATL cell viability more efficiently than a farnesyl transferase inhibitor FTI-277. These results not only unveil an important role for protein geranylgeranylation in ATL cell survival, but also implicate therapeutic potentials of statins in the treatment of ATL.
authors.affiliation: Department of Molecular Virology, Graduate School of Medicine, Tokyo Medical and Dental University, 1-5-45 Bunkyo-ku, Tokyo 113-8510, Japan.
authors.forename: Mizuho
authors.initials: M
authors.lastname: Nonaka
authors.forename: Shin
authors.initials: S
authors.lastname: Uota
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Saitoh
authors.forename: Mayumi
authors.initials: M
authors.lastname: Takahashi
authors.forename: Haruyo
authors.initials: H
authors.lastname: Sugimoto
authors.forename: Tohti
authors.initials: T
authors.lastname: Amet
authors.forename: Ayako
authors.initials: A
authors.lastname: Arai
authors.forename: Osamu
authors.initials: O
authors.lastname: Miura
authors.forename: Naoki
authors.initials: N
authors.lastname: Yamamoto
authors.forename: Shoji
authors.initials: S
authors.lastname: Yamaoka
mesh_terms: D000328:Adult; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D001549:Benzamides / Q000494:pharmacology; D053148:Caspase 3 / Q000378:metabolism; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology; D020672:I-kappa B Proteins / Q000378:metabolism; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000378:metabolism / Q000473:pathology; D008715:Methionine / Q000031:analogs & derivatives / Q000494:pharmacology; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D011106:Polyisoprenyl Phosphates / Q000494:pharmacology; D017368:Protein Prenylation / Q000502:physiology*; D012717:Sesquiterpenes / Q000494:pharmacology; D020696:rab5 GTP-Binding Proteins / Q000378:metabolism; D020830:rac1 GTP-Binding Protein / Q000378:metabolism
chemical_list: D001549:Benzamides; D004791:Enzyme Inhibitors; C096856:FTI 277; C102521:GGTI 298; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D020672:I-kappa B Proteins; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D011106:Polyisoprenyl Phosphates; C107953:RAC1 protein, human; D012717:Sesquiterpenes; D000072000:NF-KappaB Inhibitor alpha; C004808:farnesyl pyrophosphate; D008715:Methionine; D053148:Caspase 3; D020696:rab5 GTP-Binding Proteins; D020830:rac1 GTP-Binding Protein; C002963:geranylgeranyl pyrophosphate