183 research outputs found
The "backdoor pathway" of androgen synthesis in human male sexual development.
Mammalian sex determination (male versus female) is largely controlled by genes, whereas sex differentiation (development of reproductive structures) is largely controlled by hormones. Work in the 20th century indicated that female external anatomy was a "default" pathway of development not requiring steroids, whereas male genital development required testicular testosterone plus dihydrotestosterone (DHT) made in genital skin according to a "classic" pathway. Recent work added the description of an alternative "backdoor" pathway of androgen synthesis discovered in marsupials. Unique "backdoor steroids" are found in human hyperandrogenic disorders, and genetic disruption of the pathway causes disordered male sexual development, suggesting it plays an essential role. O'Shaughnessy and colleagues now show that the principal human backdoor androgen is androsterone and provide strong evidence that it derives from placental progesterone that is metabolized to androsterone in nontesticular tissues. These studies are essential to understanding human sexual development and its disorders
Use of Prednisone With Abiraterone Acetate in Metastatic CastrationâResistant Prostate Cancer
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140033/1/onco1231.pd
In Reply
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/139931/1/oncoe14.pd
Perfil caracterĂstico das atividades 17-hidroxilase e 17,20-liase reveladas por meio do metaboloma de esteroides urinĂĄrios de pacientes com deficiĂȘncia de CYP17
OBJECTIVES: (1) Characterize serum (S) and urinary (U) steroid metabolites in complete CYP17 deficiency (cCYP17D); (2) analyze the relative 17α-hydroxylase (17OH) and 17,20-lyase (17,20L) activities in vivo; and (3) comparedata from the two most prevalent mutations in Brazil. SUBJECTS AND METHODS: 20 genotyped cCYP17D patients from a previously reported cohort were homozygous for W406R or R362C; 11 controls were CYP17 wild types (WT). WT and cCYP17D patients had S and U samples drawn to measure: cortisol (F), corticosterone (B), deoxycorticosterone (DOC), 18OH-B, 18OH-DOC, and 17OHP; and tetrahydro (TH)-B, THA, THDOC, THF+5α-THF, TH-cortisone, androsterone, etiocholanolone, 5-pregnenediol, 17OH-pregnenolone and pregnanetriol. RESULTS: Compared to WT, cCYP17D patients had marked elevations of B, DOC, 18OH-B and 18OH-DOC, whereas 17OHP, F and adrenal androgens (AA) were reduced; U steroids parallel S findings. Metabolite ratios revealed that both 17OH and 17,20L activities were impaired in cCYP17D. There were nodifferences between W406R andR362C mutations. CONCLUSIONS: cCYP17D patients show parallel overproduction/overexcretion of 17-deoxysteroids, and marked reduction of F and AA. In addition to 17OH, 17,20-L activity was also impaired in cCYP17D. W406 and R362C mutations disclose similar Sand U patterns.OBJETIVOS: (1) Caracterizar os esteroides sĂ©ricos (S) e urinĂĄrios (U) na deficiĂȘncia completa da CYP17 (DcCYP17); (2) analisar as atividades da 17α-hidroxilase (17OH) e 17,20-liase (17, 20 L) in vivo; e (3) comparar as duas mutaçÔes mais prevalentes no Brasil. SUJEITOS E MĂTODOS: 20 pacientes genotipados para a DcCYP17, de uma coorte anterior, eram homozigotos para W406R ou R362C (8 cada); 11 controles eram CYP17 wild types (WT). Amostras de S e U foram colhidas dos WT e pacientes para dosagem de: cortisol (F), corticosterona (B), deoxicorticosterona (DOC), 18-OH-B, 18OH-DOC e 17OHP; e tetraidro(TH)-B, THA, TH-DOC, THF+5α-THF, THE, androsterona, etiocolanolona, 5-pregnenediol, 17OH-pregnenolona e pregnanetriol. RESULTADOS: Comparados aos WT, os pacientes com DcCYP17 revelaram elevaçÔes acentuadas de B, DOC, 18OHB e 18OHDOC, enquanto 17OHP, F e andrĂłgenos adrenais (AA) estavam reduzidos. Os esteroides na U acompanham os achados no S. As relaçÔes de metabĂłlitos mostraram que as atividades de 17OH e 17,20L estavam reduzidas em pacientes com DcCYP17. NĂŁo houve diferenças entre pacientes com as mutaçÔes W406R e R362C. CONCLUSĂES: Na DcCYP17, a produção e a excreção dos 17-deoxiesteroides estĂŁo aumentadas em paralelo, em contraste com a reduzida produção/excreção de F e AA. As atividades da 17OH e 17,20-L estĂŁo diminuĂdas na DcCYP17. As mutaçÔes W406 e R362C apresentam achados semelhantes em S e U.Universidade Federal de SĂŁo Paulo (UNIFESP) Department of Medicine Division of Endocrinology and MetabolismUniversity of Texas Southwestern Medical Center Department of Clinical SciencesUniversity of Birmingham Division of Medical SciencesUNIFESP, Department of Medicine Division of Endocrinology and MetabolismSciEL
Development and Validation of a Novel LCâMS/MS Method for Simultaneous Determination of Abiraterone and its Seven Steroidal Metabolites in Human Serum: Innovation in Separation of Diastereoisomers Without Use of a Chiral Column
Abiraterone acetate (AA), the prodrug of abiraterone, is FDA-approved for the treatment of castration-resistant prostate cancer. Abiraterone is metabolized in patients to a more potent analogue, D4A. However, we have recently reported that this analogue is further metabolized to additional metabolites in patients treated with AA. Here, we present a liquid chromatography-tandem mass spectrometry method developed to resolve and detect abiraterone and its seven metabolites in human serum using an AB Sciex Qtrap 5500 mass analyzer coupled with a Shimadzu Nexera UPLC station. Analytes and the internal standard (abiraterone-d4) were extracted from human serum using the liquidâliquid extraction procedure. The analytes were separated using a Zorbax Eclipse Plus C18 150 Ă 2.1 mm, 3.5 ÎŒm column at 40 °C and an isocratic mobile phase 35% A (0.1% formic acid in water), 65% B (0.1% formic acid in methanol:acetonitrile; 60:40). Electrospray ionization in positive mode was applied with multiple reaction monitoring in a total run time of 13 min. Abiraterone detection was linear in the range 2â400 ng/mL and all metabolites from 0.1â20 ng/mL. The method was validated following US FDA guidelines for bioanalytical method validation, and all the metabolite results were within the acceptance limits. Despite the similarity in structure and mass transition between the metabolites, the validated method separated all the metabolites, including diastereomers, to allow accurate identification and quantitation of each compound
Levoketoconazole: a novel treatment for endogenous Cushing's syndrome.
Introduction: Endogenous Cushing's syndrome (CS) is a rare, life-threatening endocrine disorder that is caused by chronic exposure to cortisol overproduction. Levoketoconazole (Recorlev), a 2S, 4R stereoisomer of ketoconazole, is a steroidogenesis inhibitor under investigation for the treatment of CS. Areas covered: This review covers the pharmacology, efficacy, and safety of levoketoconazole for the treatment of patients with endogenous CS. Expert opinion: Based on the preclinical and clinical pharmacology findings, levoketoconazole appears to be the relevant enantiomer of ketoconazole for inhibition of steroidogenesis, with more potent inhibition of both cortisol and androgen synthesis relative to ketoconazole racemate and the 2R, 4S stereoisomer dextroketoconazole. Results from the phase III SONICS study showed that levoketoconazole was effective in normalizing cortisol levels and improving biomarkers of cardiovascular risk in a significant percentage of patients. In addition, treatment with levoketoconazole showed improvements in subjective clinical assessments of clinician-rated CS clinical signs and symptoms, patient-reported quality of life, and depression symptom severity. Testosterone levels decreased significantly in women. Levoketoconazole had an acceptable safety profile with no unexpected safety signals. The favorable pharmacology, efficacy, and safety profile of levoketoconazole supports its use as medical therapy for CS, if approved
Human cytochrome P450 17A1 structures with metabolites of prostate cancer drug abiraterone reveal substrate-binding plasticity and a second binding site
Abiraterone acetate is a first-line therapy for castration-resistant prostate cancer. This prodrug is deacetylated in vivo to abiraterone, which is a potent and specific inhibitor of cytochrome P450 17A1 (CYP17A1). CYP17A1 performs two sequential steps that are required for the biosynthesis of androgens that drive prostate cancer proliferation, analogous to estrogens in breast cancer. Abiraterone can be further metabolized in vivo on the steroid A ring to multiple metabolites that also inhibit CYP17A1. Despite its design as an active-siteâdirected substrate analog, abiraterone and its metabolites demonstrate mixed competitive/noncompetitive inhibition. To understand their binding, we solved the X-ray structures of CYP17A1 with three primary abiraterone metabolites. Despite different conformations of the steroid A ring and substituents, all three bound in the CYP17A1 active site with the steroid core packed against the I helix and the A ring C3 keto or hydroxyl oxygen forming a hydrogen bond with N202 similar to abiraterone itself. The structure of CYP17A1 with 3-keto, 5α-abiraterone was solved to 2.0 Ă
, the highest resolution to date for a CYP17A1 complex. This structure had additional electron density near the F/G loop, which is likely a second molecule of the inhibitor and which may explain the noncompetitive inhibition. Mutation of the adjacent Asn52 to Tyr positions its side chain in this space, maintains enzyme activity, and prevents binding of the peripheral ligand. Collectively, our findings provide further insight into abiraterone metabolite binding and CYP17A1 function
DeficiĂȘncia combinada de 17α-hidroxilase/17,20 liase devido Ă mutação p.R96W no gene CYP17 em um paciente brasileiro
Congenital adrenal hyperplasia (CAH) resulting from 17α-hydroxylase/17,20-lyase deficiency is a rare autosomal recessive disease and the second most common form of CAH in Brazil. We describe the case of a Brazilian patient with CYP17 deficiency (17α-hydroxylase/17,20-lyase deficiency) caused by a homozygous p.R96W mutation on exon 1 of the CYP17 gene, an unusual genotype in Brazilian patients with this form of CAH. The patient, raised as a normal female, sought medical care for lack of pubertal signs and primary amenorrhea at the age of 16 years. At evaluation, the presence of a 46,XY karyotype, hypertension and hypokalemia were observed. We emphasize the recognition of CYP17 deficiency in the differential diagnosis of cases of hypergonadotrophic hypogonadism and hypertension in young patients who need specific treatment for both situations.A hiperplasia adrenal congĂȘnita (HAC), em razĂŁo da deficiĂȘncia de 17α-hidroxilase/17,20-liase, Ă© uma doença autossĂŽmica recessiva rara e a segunda causa mais comum de HAC no Brasil. Descrevemos o caso de um paciente brasileiro portador da deficiĂȘncia 17α-hidroxilase/17,20- liase (CYP17) em homozigose para a mutação p.R96W no Ă©xon 1 do gene da CYP17A1, uma mutação incomum entre os casos brasileiros descritos com essa forma de HAC. Esse paciente, criado como um indivĂduo normal do sexo feminino, procurou atendimento por ausĂȘncia de sinais puberais e amenorreia primĂĄria aos 16 anos de idade. Durante a avaliação, constataram-se um cariĂłtipo 46,XY e a presença de hipertensĂŁo e hipocalemia. Enfatizamos o reconhecimento da deficiĂȘncia da CYP17 dentre os possĂveis diagnĂłsticos em um paciente jovem com hipogonadismo hipergonadotrĂłfico e hipertensĂŁo, os quais necessitam de tratamento particularizado para ambas as situaçÔes.Universidade Federal do Rio Grande do Sul Hospital de ClĂnicas de Porto AlegreUniversidade Federal de SĂŁo Paulo (UNIFESP) Escola Paulista de Medicina Department of MedicineUniversity of Texas Southwestern Medical Center Department of Internal MedicineUNIFESP, EPM, Department of MedicineSciEL
Long-term efficacy and safety of osilodrostat in patients with Cushingâs disease: results from the LINC 4 study extension
ObjectiveTo evaluate the long-term efficacy and safety of osilodrostat in patients with Cushingâs disease.MethodsThe multicenter, 48-week, Phase III LINC 4 clinical trial had an optional extension period that was initially intended to continue to week 96. Patients could continue in the extension until a managed-access program or alternative treatment became available locally, or until a protocol amendment was approved at their site that specified that patients should come for an end-of-treatment visit within 4 weeks or by week 96, whichever occurred first. Study outcomes assessed in the extension included: mean urinary free cortisol (mUFC) response rates; changes in mUFC, serum cortisol and late-night salivary cortisol (LNSC); changes in cardiovascular and metabolic-related parameters; blood pressure, waist circumference and weight; changes in physical manifestations of Cushingâs disease; changes in patient-reported outcomes for health-related quality of life; changes in tumor volume; and adverse events. Results were analyzed descriptively; no formal statistical testing was performed.ResultsOf 60 patients who entered, 53 completed the extension, with 29 patients receiving osilodrostat for more than 96 weeks (median osilodrostat duration: 87.1 weeks). The proportion of patients with normalized mUFC observed in the core period was maintained throughout the extension. At their end-of-trial visit, 72.4% of patients had achieved normal mUFC. Substantial reductions in serum cortisol and LNSC were also observed. Improvements in most cardiovascular and metabolic-related parameters, as well as physical manifestations of Cushingâs disease, observed in the core period were maintained or continued to improve in the extension. Osilodrostat was generally well tolerated; the safety profile was consistent with previous reports.ConclusionOsilodrostat provided long-term control of cortisol secretion that was associated with sustained improvements in clinical signs and physical manifestations of hypercortisolism. Osilodrostat is an effective long-term treatment for patients with Cushingâs disease.Clinical trial registrationClinicalTrials.gov, identifier NCT0218021
- âŠ