Boronated metalloporphyrins: a novel approach to the diagnosis and treatment of cancer using contrast-enhanced MR imaging and neutron capture therapy.
Porphyrins are a unique class of metal chelating agents that have shown specific affinity for neoplasms. The water-soluble free-base derivative, tetrakiscarborane carboxylate ester of 2,4-(alpha,beta-dihydroxyethyl) deuteroporphyrin IX (BOPP), an agent designed for neutron capture therapy, has previously demonstrated selective localization and retention in a C6 murine glioma. In the present work, the authors demonstrate that the manganese chelate of BOPP also selectively localizes in a rat 9L gliosarcoma and preferentially enhances the tumor-normal brain contrast of T1-weighted images for at least 92 hours. The data indicate a maximal enhancement of contrast between tumor and normal brain at 24 hours after injection, compared with 5 minutes for manganese (III) tetraphenylporphine sulfonate (TPPS4). The results also indicate that Mn-BOPP may have a slower uptake in the 9L glioma than Mn-TPPS4 but a longer retention in the tumor. Mn-BOPP is unique in that it represents, to the authors' knowledge, the first example of a single agent that can enhance contrast between tumor and normal tissue and be potentially effective as an agent for boron neutron capture therapy.
Huang
L R
LR
Department of Biophysics, Roswell Park Cancer Institute, Buffalo, NY 14263.
Straubinger
R M
RM
Kahl
S B
SB
Koo
M S
MS
Alletto
J J
JJ
Mazurchuk
R
R
Chau
R I
RI
Thamer
S L
SL
Fiel
R J
RJ
D000818:Animals; D001896:Boron Compounds / Q000627:therapeutic use; D016754:Boron Neutron Capture Therapy; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000532:radiotherapy*; D003905:Deuteroporphyrins / Q000627:therapeutic use; D008665:Metalloporphyrins; D051381:Rats; D011916:Rats, Inbred F344; D014407:Tumor Cells, Cultured; D000098851:Carboranes
D001896:Boron Compounds; D003905:Deuteroporphyrins; D008665:Metalloporphyrins; C080251:2,4-(alpha,beta-dihydroxyethyl)deuteroporphyrin IX tetrakiscarborane carboxylate ester; D000098851:Carboranes; C056661:manganese(III)tetraphenylporphine sulfonate