The impact of testosterone, tibolone and black cohosh on purified mammary and placental 17ß-hydroxysteroid dehydrogenase type 1.

CONTEXT: Mammary and placental 17ß-hydroxysteroid dehydrogenase type 1 (17ßHSD1). OBJECTIVE: To assess the impact of testosterone, tibolone, and black cohosh on purified mammary and placental 17ßHSD1. MATERIALS AND METHODS: 17ßHSD1 was purified from human mammary gland and placenta by column chromatography, its activity was monitored by a radioactive activity assay, and the degree of purification was determined by gel electrophoresis. Photometric cofactor transformation analysis was performed to assess 17ßHSD1 activity without or in presence of testosterone, tibolone and black cohosh. RESULTS: 17ßHSD1 from both sources displayed a comparable basal activity. Testosterone and tibolone metabolites inhibited purified mammary and placental 17ßHSD1 activity to a different extent, whereas black cohosh had no impact. DISCUSSION: Studies on purified enzymes reveal the individual action of drugs on local regulatory mechanisms thus helping to develop more targeted therapeutic intervention. CONCLUSION: Testosterone, tibolone and black cohosh display a beneficial effect on local mammary estrogen metabolism by not affecting or decreasing local estradiol exposure.

Assessment of progesterone receptors in breast carcinoma by PET with 21-18F-fluoro-16α,17α-[(R)-(1'-α-furylmethylidene)dioxy]-19-norpregn-4-ene-3,20-dione.

UNLABELLED: This first-in-human study was designed to evaluate the safety and dosimetry of the progesterone analog 21-(18)F-fluoro-16α,17α-[(R)-(1'-α-furylmethylidene)dioxy]-19-norpregn-4-ene-3,20-dione ((18)F-FFNP), as well the feasibility of imaging tumor progesterone receptors (PRs) by PET in breast cancer. METHODS: Women with breast cancer underwent PET with (18)F-FFNP. Tumor (18)F-FFNP uptake was assessed semiquantitatively by determining maximum standardized uptake value and tumor-to-normal breast (T/N) activity ratio and by Logan graphical analysis. The PET results were correlated with estrogen receptor (ER) and PR status, assessed by in vitro assays of the tumor tissue. The biodistribution of (18)F-FFNP was measured in patients by whole-body PET, and human dosimetry was estimated. RESULTS: Twenty patients with 22 primary breast cancers (16 PR-positive [PR+] and 6 PR-negative [PR-]) were evaluated. Tumor maximum standardized uptake value was not significantly different in PR+ and PR- cancers (mean ± SD, 2.5 ± 0.9 vs. 2.0 ± 1.3, P = 0.386), but the T/N ratio was significantly greater in the PR+ cancers (2.6 ± 0.9 vs. 1.5 ± 0.3, P = 0.001). In addition, there was a significant correlation between distribution volume ratio and T/N ratio (r = 0.89; P = 0.001) but not between distribution volume ratio and either PR status or standardized uptake value, likely because of small sample size. On the basis of whole-body PET data in 12 patients, the gallbladder appeared to be the dose-limiting organ, with an average radiation dose of 0.113 mGy/MBq. The whole-body dose was 0.015 mGy/MBq, and the effective dose was 0.020 mSv/MBq. No adverse effects of (18)F-FFNP were encountered. CONCLUSION: (18)F-FFNP PET is a safe, noninvasive means for evaluating tumor PRs in vivo in patients with breast cancer. The relatively small absorbed doses to normal organs allow for the safe injection of up to 440 MBq of (18)F-FFNP.

Bromine- and iodine-substituted 16alpha,17alpha-dioxolane progestins for breast tumor imaging and radiotherapy: synthesis and receptor binding affinity.

Progesterone receptors (PRs) are present in many breast tumors, and their levels are increased by certain endocrine therapies. We describe the synthesis and PR binding affinities of a series of bromine- and iodine-substituted 16alpha,17alpha-dioxolane progestins, some of which, when appropriately radiolabeled, are potential agents for diagnostic imaging of PR-positive breast tumors using positron emission tomography (PET) and for radiotherapy. These compounds were synthesized from halogenated furanyl, phenyl, and thiophenyl aldehydes and a progestin 16alpha,17alpha,21-triol (5) in the presence of HClO4 or Sc(OTf)3 in high yields under optimized conditions. A new reagent, perfluoro-1-butanesulfonyl fluoride (PBSF), was used to convert the C-21 OH to F in high yields. The relative binding affinities (RBAs) of the most promising compounds for the PR (RBA of R5020 = 100) were 16alpha,17alpha-[(R)-1'-alpha-(5-bromofurylmethylidene)dioxyl]-21-hydroxy-19-norpregn-4-ene-3,20-dione (endo-6; RBA = 65 and moderate lipophilicity), 21-fluoro-16alpha,17alpha-[(R)-1'-alpha-(5-iodofurylmethylidene)dioxyl]-19-norpregn-4-ene-3,20-dione (endo-14; RBA = 40) and 21-fluoro-16alpha,17alpha-[(S)-1'-beta-(4-iodophenylmethylidene)dioxyl]-19-norpregn-4-ene-3,20-dione (exo-16; RBA = 34).

An efficient route for the preparation of a 21-fluoro progestin-16 alpha,17 alpha-dioxolane, a high-affinity ligand for PET imaging of the progesterone receptor.

Two different synthetic routes were explored for the synthesis of fluoro furanyl norprogesterone (FFNP) 1, a high-affinity ligand for the progesterone receptor (PgR) that is being developed as a PET imaging agent for PgR-positive breast cancer. Both approaches proceed through a key intermediate, triol 5. The first approach, starting from keto-ketal 2, employed a dioxenyl group as a synthon for installing a corticosteroid side chain in keto-alcohol 4. The second approach, starting from propargylic acetate 12b, involved the application of a two-step method, a Pd(II)-catalyzed oxidative rearrangement followed by a base-catalyzed acetate rearrangement of the intermediate unsaturated acetate 13b, to generate the requisite corticosteroid side chain in keto-acetate 14b. This intermediate was further elaborated to the final product 1 via efficient dihydroxylation with potassium permangnate, furan acetalization with scandium triflate, and mesylation and fluorination reactions. The palladium-catalyzed route is considerably more efficient than the dioxene approach for the synthesis of key intermediate triol 5, and the scandium triflate-catalyzed acetalization, in particular, led to a considerable improvement in the overall yield of the endo furan acetal alcohol 16a. This route provides a major improvement in the overall yield of the final progestin target, FFNP 1.

Synthesis of (3alpha,7beta,17alpha)-7-methyl-19-norpregn-5(10)-en-20-yne-3,7,17-triol, a metabolite of ORG OD14, and its 7-epimer.

The syntheses of the 7beta-hydroxy metabolite of ORG OD14 (Livial((R))), (3alpha,7beta,17alpha)-7-methyl-19-norpregn-5(10)-en-20-yne-3,7,17-triol (35), and its 7-epimer, (3alpha,7alpha,17alpha)-7-methyl-19-norpregn-5(10)-en-20-yne-3,7,17-triol (11), are described.

Synthesis of (3alpha,7beta, 17alpha)-7-methyl-19-norpregn-5(10)-en-20-yne-3,7,17-triol, a metabolite of ORG OD14, and its 7-epimer.

The syntheses of the 7beta-hydroxy metabolite of ORG OD14 (Livial), (3alpha,7beta, 17alpha)-7-methyl-19-norpregn-5(10)-en-20-yne-3,7,17-t riol (35), and its 7-epimer, (3alpha,7alpha, 17alpha)-7-methyl-19-norpregn-5(10)-en-20-yne-3,7,17-t riol (11), are described.

Prodrugs of gestodene for matrix-type transdermal drug delivery systems.

PURPOSE: The aim of this study was to enhance the transdermal absorption of the highly active progestin gestodene from matrix type transdermal delivery systems (TDDS) by formation of prodrugs with improved matrix solubility. METHODS: Gestodene esters were synthesized via acylation of the drug with the respective carboxylic anhydrides. Subsequently TDDS were produced using the solvent cast method. Selected formulations were examined with in vitro diffusion experiments using skin of nude mice. RESULTS: One prodrug, gestodene caproate proved to be an oil at ambient temperature and showed a very high solubilty of over 10.5% in the TDDS matrix. Within in vitro penetration studies using those systems the prodrug exhibited a significantly higher transdermal penetration rate than gestodene from reference systems. Furthermore, the prodrug was hydrolyzed to the parent drug to a high extent during the passage of the skin. CONCLUSIONS: Designing prodrugs to the requirements of matrix TDDS is an efficient way of enhancing the transdermal drug flux rate.

Fluorine-18-labeled progestin ketals: synthesis and target tissue uptake selectivity of potential imaging agents for receptor-positive breast tumors.

We have studied two new fluorine-substituted progestins as potential imaging agents for progesterone-receptor-positive human breast tumors. The steroids are 16 alpha, 17 alpha-fluoroacetophenone ketals of 16 alpha, 17 alpha-dihydroxyprogesterone and 16 alpha, 17 alpha, 21-trihydroxy-19-norprogesterone. Synthesis of the latter compound in seven steps from 19-norandrost-4-ene-3,17-dione is reported. Both compounds demonstrate high affinity for the progesterone receptor (PgR) (52.5 and 240%, respectively, relative to R5020 = 100). The syntheses were adapted to 18F-labeling with 4'-[18F]-fluoroacetophenone, prepared from 4'-nitroacetophenone by nucleophilic substitution with K18F/Kryptofix. Considerable adjustment of reaction conditions was required to effect ketalization using tracer quantities of the ketone. In tissue distribution studies in estrogen-primed immature female rats, both ketals showed selective uterine uptake, which was blocked by coinjection of a saturating dose of the unlabeled progestin ORG 2058. Additionally, metabolic stability of the radiolabel was indicated by the low radioactivity levels seen in bone. Both compounds showed relatively high uptake in fat, in accord with their relative lipophilicities demonstrated by HPLC-derived octanol-water partition coefficients. The selective uterine uptake and metabolic stability of these compounds suggests that this class of PgR ligands might be promising for the selective imaging of receptor-positive tumors if derivatives of reduced lipophilicity can be prepared.

Synthesis and evaluation of (17 alpha,20E)21-[125I]iodo-11-substituted-19-norpregna-1,3,5(10), 20-tetraene-3,17 beta-diols: the influence of 11-stereochemistry on tissue distribution of radioiodinated estrogens.

The 21-tri-n-butylstannyl derivatives of (17 alpha,20E)-11 alpha and beta-methoxy-19-norpregna-1,3,5(10),20-tetraene-3,17 beta-diol were synthesized and characterized. These compounds, as well as the 11-unsubstituted compound were converted via electrophilic ipso radioiododestannylation to the corresponding 21[125I]iodo analogs at the no-carrier-added level in 73-90% isolated radiochemical yields. The radiochemical 4c [IV alpha ME2, (17,20E)-21[125I]iodo-11 alpha-methoxy-19-norpregna-1,3, 5(10),20-tetraene-3,17 beta-diol] was evaluated in immature female rats and the results compared to those previously reported for 4a (IVE2) and 4b (IV beta ME2) to determine the influence of 11-substitution on the ability of the compounds to function as estrogen receptor-seeking agents in vivo. The results indicated that the uptake of 11 alpha-methoxy derivative in the target organ was substantially lower, of shorter duration, with a much smaller specific receptor binding component than the other two radioligands. The distribution profile of the three 17 alpha-iodovinyl estrogens paralleled that previously reported for the corresponding 17 alpha-ethynyl estrogens and this study suggests that the in vivo pharmacological results reported for the 17 alpha-ethynyl estrogens may be used to predict the in vivo behavior of the corresponding 17 alpha-iodovinyl analogs.

21-[18F]fluoro-16 alpha-ethyl-19-norprogesterone: synthesis and target tissue selective uptake of a progestin receptor based radiotracer for positron emission tomography.

We have synthesized 21-[18F]fluoro-16 alpha-ethyl-19-norprogesterone (FENP), a high affinity ligand for the progesterone receptor, labeled with the positron-emitting radionuclide fluorine-18 (t1/2 = 110 min). The synthesis proceeds in two steps from 21-hydroxy-16 alpha-ethyl-19-norprogesterone and involves [18F]fluoride ion displacement of the 21-trifluoromethanesulfonate (21-triflate). This material is purified by HPLC and is obtained in 4-30% overall yield (decay corrected) within 40 min after the end of bombardment to produce [18F]fluoride ion. The effective specific activity, determined by competitive radioreceptor binding assays, is 700-1400 Ci/mmol. In vivo, [18F]FENP demonstrates highly selective, receptor-mediated uptake by the uterus of estrogen-primed rats; the uterus to blood and uterus to muscle ratios were respectively 26 and 16 at 1 h and 71 and 41 at 3 h after injection. The high target tissue selectivity of this uptake suggests that this compound may be useful for the in vivo imaging of progestin target tissues and receptor-rich tumors (such as human breast tumors) by positron emission tomography.

[Synthesis of gestodene]. / Synthesen von Gestoden.

The synthesis of the new progestogen, 17 alpha-ethinyl-17 beta-hydroxy-18-methyl-4,15-estradien-3-one (gestodene, 6), starting from 18-methyl-4-estren-3,17-dione (1) can be accomplished by several methods. The oral progestational activity of gestodene is greater than that of levonorgestrel. Gestodene, in combination with ethinylestradiol, is contained in a recently developed oral contraceptive.

Structure and progestational activity of 13-substituted-18-norpregn-4-ene-3, 20-diones, a pilot study.

13-Ethyl-18-norpregn-4-ene-3, 20-dione (7) and 13-acetyl-18-norpregn-4-ene-3, 20-dione (4) were synthesized and tested in the s.c. Clauberg assay. The potencies of these compounds (1X and 1/3 X progesterone, respectively) are compared with those reported for 13-vinyl- and 13-cyanomethyl-18-norpregn-4-ene-3, 20-dione. A comparable activity (1/3 X progesterone) was found for 13-acetyl-18-norpregn-4-en-3-one (10) which lacks the 20-carbonyl group.