[7α-18F]fluoro-17α-methyl-5α-dihydrotestosterone: a ligand for androgen receptor-mediated imaging of prostate cancer

A remote controlled system for the preparation of 7α-[18F]fluoro-17α-methyl 5α-dihydrotestosterone ([18F]FMDHT) using microwave

“…To explore its utility as a PET imaging agent for AR, we radio-labeled FMDHT with fluorine-18 to generate 7α-[ 18 F]fluoro-17α-methyl 5α-dihydrotestosterone ([ 18 F]FMDHT) and assessed its binding and distribution in vivo. In vivo evaluations of [ 18 F]FMDHT showed preferential uptake in androgen receptor positive tissue and a low uptake in the normal tissues (Garg, et al, 2001). In biodistribution studies performed using castrated rats, the specific to non-specific uptake ratios were >7 at one hour post injection.…”

PET and SPECT Imaging of Steroid Hormone Receptors

“…Best results in baboons and rats were obtained for [ 18 F]FDHT was slower than metabolism of the other candidate tracers (Bonasera et al 1996 ;Choe et al 1995 ). [ 18 F]FDHT was able to detect AR-positive tumor lesions in prostate cancer patients, and tracer uptake was proven to be AR-mediated in humans as well (Dehdashti et al 2005 ;Larson et al 2004 18 F]FMDHT was investigated in rats treated with DES to suppress endogenous testosterone production (Garg et al 2001 ). The same authors reevaluated the suitability of […”

7α-18F-Fluoromethyl-Dihydrotestosterone and 7α-18F-Fluoromethyl-Nortestosterone: Ligands to Determine the Role of Sex Hormone–Binding Globulin for Steroidal Radiopharmaceuticals

“…In both biodistribution studies, purified 18 F-5 or 18 F-6 was reconstituted in 10% ethanol-saline and injected (via the tail vein) into mature male Sprague-Dawley rats (250 g) that had been injected subcutaneously with 1 mg of diethylstilbestrol in 0.2 mL of sesame oil 24 and 3 h before the injection of the tracer to suppress endogenous androgen biosynthesis (33). Doses of radiotracer used were 0.48 MBq (13 mCi/animal) for 18 F-5 and 0.55 MBq (15 mCi/animal) for 18 F-6.…”