Radioprotection of EMT6 tumor by a new class of radioprotectors based on a pseudo-peptide cysteamine combination.
Although WR-2721 preferentially protects normal tissues against irradiation, it seemed desirable to find other drugs presenting a lower toxicity and the same radioprotective properties. A new compound, I 102, was selected; it was characterized on one hand by a coupling between cysteamine and an amino-acid, and on the other hand by an acetyl-group, which protects the thiol function. The effects of WR-2721 and of I 102 were studied on EMT6 tumors grafted on BALB/c mice. Whatever the size of the tumor, the cell survival increased as a function of the time elapsed between the injection of I 102 and the end of the irradiation (TI). In contrast, the radioprotection afforded by WR-2721 was found to be independent of TI. The survival curves suggest that, like WR-2721, I 102 protects essentially oxygenated cells.
Lespinasse
F
F
Oiry
J
J
Fatome
M
M
Ardouin
P
P
Imbach
J
J
Malaise
E P
EP
Guichard
M
M
D004999:Amifostine / Q000494:pharmacology; D000818:Animals; D001853:Bone Marrow / Q000187:drug effects / Q000528:radiation effects; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D003543:Cysteamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D005720:Gamma Rays; D006410:Hematopoiesis / Q000187:drug effects / Q000528:radiation effects; D007928:Lethal Dose 50; D008325:Mammary Neoplasms, Experimental / Q000473:pathology / Q000532:radiotherapy*; D051379:Mice; D008807:Mice, Inbred BALB C; D011837:Radiation-Protective Agents; D013997:Time Factors; D014916:Whole-Body Irradiation
D011837:Radiation-Protective Agents; D003543:Cysteamine; C045191:I 102; D004999:Amifostine