| Project/Area Number |
06670172
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
Pathological medical chemistry
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| Research Institution | Kagoshima University |
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Principal Investigator |
HARAGUCHI Misako Faculty of Medicine, Research Associate Kagoshima University, 医学部, 助手 (10244229)
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| Co-Investigator(Kenkyū-buntansha) |
AKIYAMA Sinichi Faculty of Medicine Professor Kagoshima University, 医学部, 教授 (60117413)
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| Project Period (FY) |
1994 – 1995
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| Project Status |
Completed (Fiscal Year 1995)
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| Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1995: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1994: ¥1,600,000 (Direct Cost: ¥1,600,000)
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| Keywords | Tymidine phosphorylase / Angiogenesis / The sensitivity to anti-tumor drugs / Chick embryo chorioallantoic membrane assay / Chemtaxis / 鶏卵漿尿膜法 |
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| Research Abstract |
Human thymidine phsphorylase (dThdPase) is thought to be indentical to an angiogenic factor, Platelet-derived endothelial cell growth factor (PD-ECGF) .However, the whole amino acid sequence of dThdPase is still unknown. N-termina amino acid sequencing of dThdPase isolated human placenta gave the sequence Ac-AALMTPGTGAPPAPG.Comparison with the sequence predicted from the PD-ECGFcDNA reveals that residues 2-16 of dThdPase are indentical to that of PD-ECGF.The primary translational product of dThdPase would be processed one amino acid from the translation-initiating methionine residue and Ala-2 acetylated.
dThdPase has angiogenic activity. To investigate whether the dThdpase activity of PD-ECGF/dThdpase is indispensable to its angiogenic activity, three PD-ECGF/dThdpase mutant which have no dThdpase activity were made by site-derected mutagenesis. The lysates of COS cells transfected with the wild-type PD-ECGF/dThdpase cDNA had angiogenic activity, but those transfected with the mutant PD-ECGF/dThdpase did not. An inhibitor of dThdpase, 6-amino-5-chlorouracil, inhibited the angiogenic activity of purified dThdPase. These findings indicate that dThdpase activity is indispensable to angiogenic activity of PD-ECGF/dThdpase.
Human KB epidermal carcinoma cells transfected with PD-ECGF cDNA expressed a 55-kDa protein that was detected with anti-dThdPase antibody and the cell lysate had dThdPase activity. The sensitivity of the transfected cells to 5'-deoxy-5-fluorouridine was higher than that of untransfected KB cells. These results demonstrate that dThdPase is involved in the activation of these anticancer agents.
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