Radioprotection of EMT6 tumor by a new class of radioprotectors based on a pseudo-peptide cysteamine combination.

Abstract

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.

• Authors: F Lespinasse, J Oiry, M Fatome, P Ardouin, J Imbach, E P Malaise, M Guichard
• Journal: International journal of radiation oncology, biology, physics (Int J Radiat Oncol Biol Phys) Vol. 11 Issue 5 Pg. 1035-8 (May 1985) ISSN: 0360-3016 [Print] United States
• PMID: 2985525 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Radiation-Protective Agents
• Cysteamine
• I 102
• Amifostine

Topics

• Amifostine (pharmacology)
• Animals
• Bone Marrow (drug effects, radiation effects)
• Cell Line
• Cell Survival (drug effects, radiation effects)
• Cysteamine (analogs & derivatives, pharmacology)
• Gamma Rays
• Hematopoiesis (drug effects, radiation effects)
• Lethal Dose 50
• Mammary Neoplasms, Experimental (pathology, radiotherapy)
• Mice
• Mice, Inbred BALB C
• Radiation-Protective Agents
• Time Factors
• Whole-Body Irradiation