| Project/Area Number |
07670553
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Gastroenterology
|
|---|
| Research Institution | ASAHIKAWA MEDICAL COLLEGE |
|---|
Principal Investigator |
ONO Minoru Asahikawa medical college Lecturer, 医学部, 講師 (60185650)
|
|---|
| Project Period (FY) |
1995 – 1997
|
| Project Status |
Completed (Fiscal Year 1997)
|
| Budget Amount *help |
¥2,400,000 (Direct Cost: ¥2,400,000)
Fiscal Year 1997: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1996: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1995: ¥900,000 (Direct Cost: ¥900,000)
|
|---|
| Keywords | HBEGF / Heparin / Tunror / Hepatoma / tokim / growth / chemotherapy / Pseudomonas / heparan sulfate proteoglycan |
|---|
| Research Abstract |
Heparin-binding EGF-like growth factor (HB-EGF) is a potent mitogen for smooth muscle cell, fibroblast, and it also stimulates hepatocyte proliferation. We generated several chimeric toxins by fusing the cDNA sequence of HB-EGF and the mutant of Pseudomonas exotoxin, PE^<4E>KDEL (PE) that lacks the binding abiliy to specific receptor. HB-EGF-PE was generated by fusing the DNA fragment encoding the full length mature HB-EGF polypeptide to the N-terminus of PE^<4E>KDEL,while HB-PE was generated by fusing the 45 N-terminal heparin-binding sequence to PE^<4E>KDEL.HB-EGF-PE was capable of binding both to EGF receptor and heparan sulfate proteoglycans (HSPGs), whereas HB-PE was capable of binding only to HSPGs on the target cells. Human hepatoma cells, SK-Hep1, Hep-G2 and PLC/PRF/5 were killed in a very low concentration of HB-EGF-PE with the ID50 of 0.1 to 0.5 ng/ml. HB-PE could also killed SK-Hep1 with the ID50 of 50 ng/ml, whereas it was resistant to PE.Both exogenous EGF and heparin inhibited the cytotoxicity of HB-EGF-PE.These results indicated the existence of two alternative pathways for the internalization of the chimeric toxins defined by two different targets, EGFR and HSPGs.
|
