セラミド・シグナル調節による細胞死誘導機構の解明とその臨床的意義

• Project/Area Number: 12140203
• Research Category: Grant-in-Aid for Scientific Research on Priority Areas
• Allocation Type: Single-year Grants
• Review Section: Biological Sciences
• Research Institution: Tottori University (2004); Kyoto University (2000-2003)
• Principal Investigator: 岡崎 俊朗 鳥取大学, 医学部, 教授 (40233308)
• Co-Investigator(Kenkyū-buntansha): 中島 茂 岐阜大学, 医学部, 教授 (60188935)
• Project Period (FY): 2000 – 2004
• Project Status: Completed (Fiscal Year 2004)
• Budget Amount: ¥90,000,000 (Direct Cost: ¥90,000,000); Fiscal Year 2004: ¥21,200,000 (Direct Cost: ¥21,200,000); Fiscal Year 2003: ¥21,200,000 (Direct Cost: ¥21,200,000); Fiscal Year 2002: ¥23,800,000 (Direct Cost: ¥23,800,000); Fiscal Year 2001: ¥23,800,000 (Direct Cost: ¥23,800,000)
• Keywords: SM合成酵素 / SM合成遺伝子 / PI-3キナーゼ / ATMキナーゼ / セラミド / セラミド結合蛋白 / アポトーシス / 白血病 / スフィンゴ脂質 / メディエーター

Research Abstract

抗ガン剤に耐性となった様な細胞に細胞死を誘導することが出来るかについて、細胞レこれまでに我々の研究で明らかにされたように、抗ガン剤耐性白血病細胞ではグルコシルセラミド合成酵素(GCS)が転写レベルで活性化され、抗ガン剤によるセラミドの産生が抑制される。すなわち、抗ガン剤耐性細胞はアポトーシス誘導脂質セラミドの細胞内量を減少することで、細胞死から免れる機構を獲得することが判明した。さらに我々は、セラミド量の制御機構として、GCS以外のセラミド代謝酵素であるスフィンゴミエリン合成酵素(SMS)の細胞死ならびに増殖における意義について検討した。その結果、
(1)白血病患者から得た腫瘍細胞検体でGCSのみならずSMSの活性が、抗ガン剤耐性細胞において増強し、その結果セラミドの細胞内量が減少していることが明らかとなった。
(2)SMSの分子レベルでの解析を行うために、SM合成を欠損した細胞で発現クローニング法を用い、このSMS遺伝子を単離した。新規遺伝子クローニングーとして、SMS1と名付け、そのホモログをSMS2とrとした。
(3)SMS1の過剰発現細胞(SM(+))とSMS1の欠損細胞(SM(-))に、GCS阻害剤であるPBPPを処理したところ、濃度依存的に細胞増殖が抑制され、細胞死を誘導した。
以上のことより、セラミド代謝酵素であるSMSとGCSの活性を同時に阻害し、細胞内セラミド量を増加することで細胞死が誘導されることが明らかとなった。今後、SMSの阻害剤を開発し、同時にGCSとSMSを抑制する分子標的療法により細胞死誘導シグナル・セラミドを増強し、ベルのみならず動物レベルでも検討し、実際の臨床応用開発へと進めて行きたい。

Research Products

• [Journal Article] Astroglial expression of ceramide in Alzheimer's disease brains ; a role during neuronal apoptosis (2005)
  • Author(s): Hitoshi Satoi, et al.
  • Journal Title: Neuroscience 130(3) Pages: 657-666
• [Journal Article] Upregulation of ceramide and its regulating mechanism in a rat model of chronic cerebral ischemia (2004)
  • Author(s): Ohtani R., et al.
  • Journal Title: J Biol.Chem 1023(1) Pages: 31-40
• [Journal Article] Interleukin-2-induced survival of natural killer (NK) cells involving phosphatidylinositol-3 kinase-dependent reduction of ceramide through acid sphingomyelinase, sphingomyelin synthase and glucosylceramide synthase (2004)
  • Author(s): Taguchi Y., Kondo T., et al.
  • Journal Title: Blood 104(10) Pages: 3285-3293
• [Journal Article] Expression cloning of a human cDNA restoring sphingomyelin synthesis and cell growth in sphingomyelin synthase-defective lymphoid cells (2004)
  • Author(s): Yamaoka S., et al.
  • Journal Title: J.Biol.Chem 279 Pages: 18688-18693
• [Journal Article] Fractalkine in vascular biology : from basic research to clinical disease (2004)
  • Author(s): Umehara H., et al.
  • Journal Title: Vascular Biology 24 Pages: 34-40
• [Journal Article] Increase of nuclear ceramide through caspase-3-dependent regulation of the 'sphingomyelin (SM) cycle' in Fas-induced apoptosis (2004)
  • Author(s): Watanabe M., et al.
  • Journal Title: Cancer Res 64 Pages: 1000-1007
• [Journal Article] Ceramide reduction and transcriptional up-regulation of glucosylceramide synthase through DOX-activated Sp1 in drug-resistant HL-60/ADR cells (2004)
  • Author(s): Uchida Y.
  • Journal Title: Cancer Res 64(17) Pages: 6271-6279
• [Publications] Obuse C., Okazaki T.et al.: "Proteomics analysis of the centromere complex from HeLa interphase cells : UV-damaged DNA binding protein 1 (DDB-1) is a component of the CEN-complex, while BMI-1 is transiently co-localized with the centromeric region in interphase"Genes Cells.. 9(2). 105-120 (2004)
• [Publications] Watanabe M., Okazaki T.et al.: "Increase of nuclear ceramide through caspase-3-dependent regulation of the "sphingomyelin cycle" in Fas-induced apoptosis."Cancer Res.. 64(3). 1000-1007 (2004)
• [Publications] Okazaki T,. Laali KK.: "Carbocations (M + H)(+) and oxidation dications (M(2+)) from benzo[a]pyrene and its nonalternant isomers azulenophenalenes : a theoretical(DFT, GIAO, NICS) study."J Org Chem.. 69(2). 510-516 (2004)
• [Publications] Okazaki T., Kohno S., et al.: "Neuroblastoma detected by mass screening : the Tumor Board's role in its treatment."Pediatr Surg Int.. 20(1). 27-32 (2004)
• [Publications] Kobayashi H., Okazaki T.et al.: "Increased levels of circulating adhesion molecules in neonates with congenital diaphragmatic hernia complicated by persistent pulmonary hypertension."Pediatr Surg Int.. 20(1). 19-23 (2004)
• [Publications] Iyoda K., Okazaki T.et al.: "The prospective study of vaccines for children following febrile seizures--a questionnaire survey in Hiroshima prefecture"No To Hattatsu.. 35(6). 532-534 (2003)
• [Publications] Kondo T., Okazaki T.et al.: "Control of ceramide-induced apoptosis by IGF-1 : involvement of PI-3 kinase, cas pase-3 and catalase"Cell Death Difference. 9. 682-692 (2002)
• [Publications] Kondo T., Okazaki T.et al.: "Vesnarinone causes oxidative damage by inhibiting catalase function through ceramide action in myeloid cell apoptosis"Molecular Pharmacology. 61(3). 620-627 (2002)
• [Publications] Kawase M., Okazaki T et al.: "Increase of ceramide in adriamycin-induced HL-60 cell apoptosis : detection by a novel anti-ceramide antibodody"Biochimica et Biophysica Acta. 1584. 104-114 (2002)
• [Publications] Goda S., Okazaki T, et al.: "Fractalkine, a CX3C-chemokine, functions predominantly as an adhesion molecule in monocytic cell line THP-1"Immunology and Cell Biology. 79. 298-302 (2001)
• [Publications] Huang J-Y., Okazaki T.et al.: "Differential interaction of Cbl with Grb2 and CrkL in CD-2 mediate NK cell activation"Mol. Immunol.. 37. 1057-1065 (2001)
• [Publications] Umehara H., Okazaki T, et al.: "Role for adapter proteines in costimulatory signals of CD2 and IL-2 on NK cell activation"Mol. Immunol.. 38. 587-596 (2001)
• [Publications] Umehara H., Okazaki T, et al.: "Fractalkine and vascular injury"Trends in Immunology. 22(11). 602-607 (2001)
• [Publications] Yabu T., Okazaki T.et al.: "Characterization of zebrafish caspase-3 and induction of apoptosis through ceramide generation in fish FHM cells and zebrafish embryo"Biochem. J.. 360(1). 39-47 (2001)
• [Publications] Kondo T,Okazaki T. et al: "Role of c-jun expression increased by heat shock-and ceramide-activated cas pase-3 in HL-60 cell apoptosis : Possible involvement of ceramide in heat shock-indeced apoptpsis"J.Biol.Cem.. 275. 7668-7676 (2000)
• [Publications] Kondo T,Okazaki T. et al: "Suppression of heat shock protein-70 by ceramide in heat shock-induced HL-60 cell apoptosis"J.Biol.Chem. 275. 8872-8879 (2000)
• [Publications] Iwai K.,Okazaki T. et al: "Fulminant hepatitis B following bone marrow transplantation in a Hbs Ag-negative, Hbs Ab-positive recipient ; reactivation of dormant virus diring immunosuppressive period"Bone Marrow transplantation. 25. 105-108 (2000)
• [Publications] Goda S,Okazaki T. et al: "CX3C-chemokaine, fractalkine enhanced adhesion of THP-1 cells to endotherial cells through integrin-dependent and independent mechanisms"J.Immunolo.. 164. 4313-4320 (2000)
• [Publications] Yoneda O,Okazaki T. et al: "Fractalkine-mediated endotherial cell injury by NK cells"J.Immunolo.. 164. 4055-4062 (2000)
• [Publications] Kondo T,Okazaki T. et al.: "Inhibition of ceramide-induced caspase-3 and lipid peroxidation by PI-3kinase ; Role of insulin growth factor-1 in ceramide mediated HL-60 cell apoptosis"Mol.Biolo.Cell. 11,Supl.. 253a (2000)