Bromine-80m radiotoxicity and the potential for estrogen receptor-directed therapy with auger electrons.
While theoretically feasible, estrogen receptor (ER)-directed radiotherapy of hormone-dependent cancers has not been realized because no ER-seeking ligand with an appropriate radiotoxic potential has been identified. Since an appropriate nuclide is a key component we studied the 4.4-h half-life, Auger electron-emitting nuclide bromine-80m. When incorporated into DNA this nuclide was radiotoxic to cells in culture and caused substantial chromosomal damage, while similar concentrations of bromine-80m as bromide or bromoantipyrine were without effect. The mean lethal dose for bromine-80m was 45 atoms per nucleus which is consistent with use in receptor-positive cancers with limited numbers of ER.
DeSombre
E R
ER
Ben May Institute, University of Chicago, Illinois 60637.
Harper
P V
PV
Hughes
A
A
Mease
R C
RC
Gatley
S J
SJ
DeJesus
O T
OT
Schwartz
J L
JL
D000818:Animals; D001967:Bromine Radioisotopes / Q000633:toxicity*; D001973:Bromodeoxyuridine; D002460:Cell Line; D004249:DNA Damage; D004583:Electrons; D006207:Half-Life; D008722:Methods; D009376:Neoplasms, Hormone-Dependent / Q000532:radiotherapy*; D011960:Receptors, Estrogen / Q000378:metabolism*
D001967:Bromine Radioisotopes; D011960:Receptors, Estrogen; D001973:Bromodeoxyuridine