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1.
Chem Biol Interact ; 390: 110872, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38244963

RESUMO

In patients with prostate carcinoma as well as in some other cancer types, the reduction of testosterone levels is desired because the hormone stimulates cancer cell growth. One molecular target for this goal is the inhibition of 17ß-hydroxysteroid dehydrogenase type 3 (17ßHSD3), which produces testosterone from its direct precursor androstenedione. Recent research in this field is trying to harness photopharmacological properties of certain compounds so that the inhibitory effect could be turned on and off by irradiation. Seven new light-switchable diazocines were investigated with regard to their inhibition of 17ßHSD3. For this purpose, transfected HEK-293 cells and isolated microsomes were treated with the substrate and the potential inhibitors with and without irradiation for an incubation period of 3 or 5 h. The amount of generated testosterone was measured by UHPLC and compared between samples and control as well as between irradiated and non-irradiated samples. There was no significant difference between samples with and without irradiation. However, four of the seven diazocines led to a significantly lower testosterone production both in cell and in microsome assays. In some of the irradiated samples, a partial destruction of the diazocines was observed, indicated by an additional UHPLC peak. However, the influence on the inhibition is negligible, because the majority of the substance remained intact. In conclusion, new inhibitors of 17ßHSD3 have been found, but so far without the feature of a light switch, since the configurational alteration of the diazocines by irradiation did not lead to a change in bioactivity. Further modification might help to find a light-switching molecule that inhibits only in one configuration.


Assuntos
Neoplasias da Próstata , Testosterona , Masculino , Humanos , Testosterona/metabolismo , Células HEK293 , Neoplasias da Próstata/metabolismo , 17-Hidroxiesteroide Desidrogenases/metabolismo , Androstenodiona/metabolismo , Androstenodiona/uso terapêutico
2.
Andes Pediatr ; 93(4): 511-519, 2022 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-37906849

RESUMO

Congenital adrenal hyperplasia (CAH) is the most common adrenal disorder in childhood. Objecti ve: To describe the clinical and laboratory characteristics of pediatric patients with CAH and perform an exploratory analysis comparing some clinical and laboratory variables according to the types of CAH. PATIENTS AND METHOD: Observational descriptive longitudinal study. Medical records from the pediatric endocrinology outpatients from four institutions in Medellín, Colombia were reviewed. Sociodemographic, clinical (type of CAH, salt-wasting crisis, associated endocrinopathies), labora tory (17-hydroxyprogesterone, testosterone, dehydroepiandrosterone sulfate, androstenedione, cor tisol, and adrenocorticotropic hormone) variables were analyzed. A descriptive statistical analysis was carried out. RESULTS: 132 patients (65% female) were included. The median age at diagnosis was 2 months, 44.7% neonatal diagnosis. Seventy-nine children with classical salt-wasting CAH, 31 with simple virilizing, and 22 with non-classical form were documented. Median 17-OHP at diagnosis was 4820 ng/dl. Sexual differentiation disorder was presented in 47% of patients and 48% presented with adrenal crisis (AC) at diagnosis; the median age of the first AC was 15 days. Ninety-three patients required fludrocortisone and 32 patients presented AC after diagnosis and treatment. Median height/ age (last appointment): -0.49 SD, difference between bone and chronological age: 26 months. More than 60% of patients had elevated androstenedione and/or testosterone at the last appointment. CONCLUSIONS: Sociodemographic and clinical characteristics are similar to those reported in the literature. In 48% of patients, AC was the initial manifestation, making neonatal screening important, as it would allow an early diagnosis. We found virilization in 71% of women in our study. A CAH should be suspected in a newborn with different genitalia.


Assuntos
Hiperplasia Suprarrenal Congênita , Recém-Nascido , Humanos , Criança , Feminino , Lactente , Pré-Escolar , Masculino , Hiperplasia Suprarrenal Congênita/complicações , Hiperplasia Suprarrenal Congênita/diagnóstico , Hiperplasia Suprarrenal Congênita/epidemiologia , Estudos Longitudinais , Androstenodiona/uso terapêutico , Testosterona/uso terapêutico , Triagem Neonatal
3.
J Clin Res Pediatr Endocrinol ; 14(2): 145-152, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34866371

RESUMO

Objective: Since there is no gold standard laboratory variable for adjustment of treatment in congenital adrenal hyperplasia (CAH), the aim was to assess the use of a 4-hour profile of serum 17-hydroxyprogesterone (17-OHP) to determine the most appropriate sample time and level of 17-OHP in predicting the metabolic control and evaluate the role of sex hormone-binding globulin (SHBG) in hyperandrogenemia. Methods: This study included children with salt-wasting CAH. Measurements for 17-OHP and cortisol were made from samples obtained before and 1, 2, and 4 hours after the morning dose of hydrocortisone. Patients were designated to have poor metabolic control when androstenedione levels according to age and sex-specific reference intervals were high and annual height standard deviation score (SDS) changes were ≥0.5. Results: The study cohort was 16 children (9 girls) with a median age of 7-years old. Premedication 17-OHP levels were strongly correlated with 17-OHP levels 1, 2, and 4 hours after the morning dose (rs=0.929, p<0.01; rs=0.943, p<0.01; rs=0.835, p<0.01, respectively). 17-OHP profiles (0, 1, 2, 4 hours) of poor (n=6) and good (n=10) metabolically controlled cases were similar. Among the patients with poor metabolic control, two cases had 17-OHP levels <2 ng/mL at all times. The remaining patients with poor metabolic control had median 17-OHP levels above 104 ng/mL, 82 ng/mL, 14 ng/mL, and 4 ng/mL, for baseline and 1, 2, and 4 hours, respectively. Differences between the poor and well-controlled group were androstenedione levels with respect to upper limit of normal [1.8 (1.5) and 0.5 (1.5) ng/mL, respectively p=0.03], annual change in height SDS [0.7 (0.2) and -0.03 (0.8) SDS, respectively, p=0.001], and daily hydrocortisone doses [7 (6) and 16 (8) mg/m2/day, respectively, p=0.02]. Androstenedione and SHBG levels were negatively correlated in the pubertal children (rs=-0.7, p=0.04). Conclusion: We conclude that: (i) a 4-hour 17-OHP profile is not useful in predicting hyperandrogenemia; (ii) suppressed levels of 17-OHP do not always indicate overtreatment; (iii) reference intervals of 17-OHP for different time periods might be of importance; (iv) low hydrocortisone doses should be avoided; and (v) SHBG could be used in pubertal children as an indicator of hyperandrogenemia.


Assuntos
Hiperplasia Suprarrenal Congênita , Anormalidades Urogenitais , 17-alfa-Hidroxiprogesterona/uso terapêutico , Hiperplasia Suprarrenal Congênita/tratamento farmacológico , Androgênios , Androstenodiona/uso terapêutico , Estatura , Criança , Feminino , Humanos , Hidrocortisona , Masculino
4.
Cell Death Dis ; 10(7): 494, 2019 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-31235695

RESUMO

Direct treatment of ER (+) breast cancer with Formestane diminishes the tumor within weeks. This is unlikely due to lack of estrogens alone. We proposed that it is the negative influence of androgens on the growth of ER(+) breast cancer. We investigated the influence of Formestane and Exemestane and of their major androgenic metabolites 4-hydroxytestosterone and 17-hydroexemestane on the proliferation of MCF-7 cells and ZR-75-1 cells. Inhibitory effects could be prevented by antiandrogens and siRNA. Activation of the AR in MCF-7 and U2-OS cells was tested by reporter gene assays. In vivo androgenicity was evaluated using the Hershberger assay. Influence on the cell cycle was demonstrated by flow-cytometry. Influence of androgens on the activity of CCND1 was demonstrated by Chip-qPCR. Antitumor activity was determined by topical treatment of DMBA tumors. We found that breast cancer cells can metabolize Formestane and Exemestane to androgenic compounds which inhibit proliferation. This can be explained by hindering the accessibility of CCND1 by histone modification. Androgenic metabolites can abolish the growth of DMBA-tumors and prevent the appearance of new tumors. The lack of cross-resistance between steroidal and nonsteroidal aromatase inhibitors is due to inhibitory effects of androgenic steroidal metabolites on the production of cyclin D1. These sterols not only inhibit proliferation of cancer cells but can also stop the growth of DMBA cancers upon direct absorption into the tumor. The quick and considerable effect on ER(+) tumors may open a new avenue for neodjuvant treatment.


Assuntos
Androgênios/metabolismo , Inibidores da Aromatase/farmacologia , Aromatase/metabolismo , Neoplasias da Mama/metabolismo , Androstenodiona/análogos & derivados , Androstenodiona/farmacologia , Androstenodiona/uso terapêutico , Animais , Antracenos/toxicidade , Aromatase/genética , Neoplasias da Mama/induzido quimicamente , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Masculino , Neoplasias Mamárias Animais/induzido quimicamente , Neoplasias Mamárias Animais/metabolismo , Piperidinas/toxicidade , Próstata/efeitos dos fármacos , Próstata/metabolismo , Ligação Proteica , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Glândulas Seminais/efeitos dos fármacos , Glândulas Seminais/metabolismo , Esteroides/farmacologia , Esteroides/uso terapêutico
5.
Pituitary ; 21(5): 445-453, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29789996

RESUMO

PURPOSE: Women with hypopituitarism have increased morbidity and mortality, and hypogonadism has been suggested to be a contributing mechanism. The purpose of this study was to investigate the prevalence of central hypogonadism and hypoandrogenism in women with hypopituitarism at a single Swedish center. METHODS: All consecutive women (n = 184) who commenced growth hormone (GH) replacement therapy at Sahlgrenska University Hospital in Gothenburg between 1995 and 2015 were included. In accordance with the Endocrine Society Clinical Practice Guidelines, strict criteria, based on menstrual history combined with laboratory measurements, were used to define central hypogonadism. Hypoandrogenism was defined as subnormal levels of dehydroepiandrosterone sulfate and/or androstenedione. RESULTS: Central hypogonadism was present in 78% of the women, in 75% of those ≤ 52 years and in 82% of those > 52 years of age. Hypoandrogenism was found in 61% of all the women and in 92% of those with adrenocorticotropic hormone (ACTH) deficiency. The estrogen substitution rate in hypogonadal women ≤ 52 years was lower than the hormonal substitution rate in the other pituitary hormone axes (74% versus 100%, P < 0.001). The use of estrogen substitution tended to decrease between 2000 and 2016. Few women received androgen treatment. CONCLUSIONS: In this first study of hypogonadism in women with hypopituitarism, using stringent diagnostic criteria for hypogonadism, the prevalence of central hypogonadism and low androgen levels was high and estrogen substitution was insufficient. Further studies are needed to elucidate the importance of hypogonadism and insufficient sex steroid replacement for the increased morbidity in hypopituitary women.


Assuntos
Hipogonadismo/epidemiologia , Adolescente , Adulto , Idoso , Androstenodiona/uso terapêutico , Sulfato de Desidroepiandrosterona/uso terapêutico , Estrogênios/uso terapêutico , Feminino , Terapia de Reposição Hormonal/métodos , Humanos , Hipogonadismo/tratamento farmacológico , Hipopituitarismo/tratamento farmacológico , Hipopituitarismo/epidemiologia , Pessoa de Meia-Idade , Testosterona/uso terapêutico , Adulto Jovem
6.
Aging Male ; 19(3): 161-167, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27558186

RESUMO

The purpose of the study was to examine the effects of acute androstenedione supplementation on hormone levels in older men at rest and during exercise. Men (n = 11) between the ages of 58 and 69 were divided into an experimental (n = 6; 62.33 ± 2.57 y) and control (n = 5; 60.2 ± 1.02 y) groups. Each participant received an oral 300 mg dose of either androstenedione (experimental) or a cellulose placebo (control) for 7 d. Pre- and post-supplementation participants completed two separate, 20-min strength tasks consisting of leg extension and leg curls at different percentages of their 10-RM. Researchers collected blood samples pre-, during, and post-exercise. Blood samples were analyzed for testosterone, androstenedione, and estradiol levels. The researchers found a significant difference between pre- (4.36 ± 56 ng/mL) and post- (5.51 ± 0.35 ng/mL) testosterone levels, as well as pre- (0.88 ± 0.20) and post- (7.46 ± 1.25) androstenedione levels, but no significant differences between pre- and post-estradiol levels for either group. It appears that short-term androstenedione supplementation augmented acute testosterone responses to resistance exercise in older men. However, further study of this supplement is needed to determine any potential it may have in mitigating andropause.


Assuntos
Androstenodiona/uso terapêutico , Suplementos Nutricionais , Testosterona/sangue , Idoso , Androstenodiona/administração & dosagem , Exercício Físico/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Testosterona/deficiência
7.
Am J Mens Health ; 10(6): NP109-NP117, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26272885

RESUMO

An increasing number of men are being diagnosed with hypogonadism. While many benefit from testosterone supplementation therapy, others who do not meet the criteria for hormone supplementation have turned to dietary adjuncts as a way or gaining improvements in libido, energy, and physical performance. These oral adjunct medications include controlled substances such as androstenedione, androstenediol as well as other "over-the-counter" options like DHEA (dehydroepiandrosterone) and herbal remedies like Tribulus terrestris This review will focus on the use of these adjunct medications in isolation, or in combination with testosterone supplementation therapy as well as the biochemical nature of the supplements, the results of scientific trials as well as the side effects that limit their use. At the end of this review, physicians will have an improved understanding of the popular testosterone adjuncts being used currently as well as the availability of these substances and how they are used.


Assuntos
Androstenodiol/uso terapêutico , Androstenodiona/uso terapêutico , Desidroepiandrosterona/uso terapêutico , Suplementos Nutricionais , Hipogonadismo/tratamento farmacológico , Testosterona/sangue , Terapia de Reposição Hormonal , Humanos , Masculino , Qualidade de Vida , Fatores de Tempo
8.
Artigo em Inglês | MEDLINE | ID: mdl-25689821

RESUMO

Huntington's disease (HD) is a progressive neurodegenerative disorder with a wide spectrum of cognitive, behavioral and motor abnormalities. The mitochondrial toxin 3-nitropropionic acid (3-NP) effectively induces specific behavioral changes and selective striatal lesions similar to that observed in HD. Some neurosteroids, synthesized in neurons and glial cells, previously showed neuroprotective abilities. 5-Androstene-3ß-17ß-diol (ADIOL) is a major metabolite of dehydroepiandrosterone (DHEA) with previously reported anti-inflammatory, anti-apoptotic and neuroprotective activities. The neuroprotective potential of ADIOL in HD was not previously investigated. Therefore, the present study investigated the neuroprotective effects of ADIOL against 3-NP-induced behavioral changes, oxidative stress, inflammation and apoptosis. Intraperitoneal administration of 3-NP (20mg/kg) for 4 consecutive days in rats caused significant loss in body weight, reduced prepulse inhibition (PPI) of acoustic startle response, locomotor hypoactivity with altered cortical/striatal histological structure, increased cortical/striatal oxidative stress, inflammation and apoptosis. Administration of ADIOL (25mg/kg, s.c.) for two days before 3-NP significantly attenuated the reduction in body weights and PPI, increased locomotor activity and restored cortical/striatal histological structure nearly to normal. Moreover, it displayed anti-oxidant, anti-inflammatory and anti-apoptotic activities as evidenced by the elevation of cortical and striatal reduced glutathione levels, reductions of cortical and striatal malondialdehyde, striatal tumor necrosis factor alpha and interleukin-6 levels. Only a small number of iNOS and caspase-3 positive cells were detected in sections from rats pretreated with ADIOL. This study suggests a potential neuroprotective role of ADIOL against 3-NP-induced Huntington's disease-like manifestations. Such neuroprotection can be attributed to its anti-oxidant, anti-inflammatory and anti-apoptotic activities.


Assuntos
Androstenodiona/uso terapêutico , Antioxidantes/uso terapêutico , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/prevenção & controle , Neurotoxinas/toxicidade , Nitrocompostos/toxicidade , Propionatos/toxicidade , Análise de Variância , Animais , Apoptose/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Caspase 3/metabolismo , Catalase/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Interações Medicamentosas , Glutationa/metabolismo , Masculino , Malondialdeído/metabolismo , Atividade Motora/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Reflexo de Sobressalto/efeitos dos fármacos
9.
Endocrine ; 47(3): 936-42, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24740546

RESUMO

We evaluated perioperative androstenedione levels in laparoscopic ovarian drilling (LOD) for polycystic ovary syndrome (PCOS) and whether an intraoperative androstenedione change was predictive for spontaneous ovulation. In a prospective study, 21 anovulatory women with clomiphene citrate-resistant PCOS who underwent LOD and eight female controls who underwent diagnostic laparoscopy for infertility were included. Perioperatively, blood was drawn one day before surgery, directly before skin incision, ten minutes after surgery, and after two days. Within three months, spontaneous ovulation occurred in 15 women (71.4 %). For both the PCOS and the control group, an androstenedione increase was found from one day before surgery to skin incision (p < 0.05). In PCOS women, there was an intraoperative androstenedione decrease (median 3.5, IQR 2.2-4.8 vs. median 2.6, IQR 1.4-2.6 ng/ml, p = 0.002). In multivariate analysis, only higher preoperative androstenedione (odds ratio, OR 6.53) and luteinizing hormone levels (OR 7.31), as well as secondary infertility (OR 5.40), were associated with higher rates of postoperative spontaneous ovulation (p < 0.001). Androstendione declines significantly during LOD. However, intraoperative kinetics are not useful for the prediction of spontaneous ovulation after LOD, in contrast to preoperative androstenedione and LH levels, as well as a history of previous pregnancies.


Assuntos
Androstenodiona/farmacocinética , Fármacos para a Fertilidade Feminina/farmacocinética , Procedimentos Cirúrgicos em Ginecologia , Laparoscopia , Período Perioperatório , Síndrome do Ovário Policístico/cirurgia , Adulto , Androstenodiona/sangue , Androstenodiona/uso terapêutico , Feminino , Fármacos para a Fertilidade Feminina/sangue , Fármacos para a Fertilidade Feminina/uso terapêutico , Humanos , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/tratamento farmacológico , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
10.
Cancer Sci ; 101(7): 1661-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20491779

RESUMO

In breast cancer, stromal cells surrounding cancer epithelial cells can influence phenotype by producing paracrine factors. Among many mediators of epithelial-stromal interactions, aromatase activity is perhaps one of the best studied. Clinical data suggest that estrogen-independent signaling leads to increased proliferation even during therapy with aromatase inhibitors (AIs). Molecular mechanism of crosstalk between the estrogen receptor (ER) and the epidermal growth factor receptor (HER) family have been implicated in resistance to endocrine therapy, but this interaction is unclear. The ability of aromatase to induce estradiol biosynthesis provides a molecular rationale to combine agents that target aromatase activity and the HER pathway. We targeted stromal-epithelial interactions using formestane, which exerts antiaromatase activity, combined with the monoclonal anti-HER2 antibody herceptin, in a subpopulation of CD44+/CD24low cells sorted from epithelial-mesenchymal co-cultures of breast cancer tissues. The growth inhibition was respectively 16% (P < 0.01) in the response to herceptin, 25% to formestane (P < 0.01), and 50% (P < 0.001) with the combination of the two drugs, suggesting that herceptin cooperates with formestane-induced inhibition of aromatase and this effect could be mediated through HER family receptors. In cells which expressed ERalpha, formestane/herceptin combination suppressed the mRNA expression of aromatase and HER2 and decreased cyclin D1 expression. These results show that combination therapies involving AIs and anti-HER2 can be efficacious for the treatment of cancer in experimental models and suggest that subtyping breast tumors gives useful information about response to treatment.


Assuntos
Androstenodiona/análogos & derivados , Anticorpos Monoclonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Antígeno CD24/imunologia , Receptores de Hialuronatos/imunologia , Androstenodiona/uso terapêutico , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Aromatase/metabolismo , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Antígeno CD24/genética , Linhagem Celular Tumoral , Primers do DNA , Receptores ErbB/efeitos dos fármacos , Receptores ErbB/fisiologia , Feminino , Humanos , Receptores de Hialuronatos/genética , RNA Neoplásico/genética , Receptor Cross-Talk , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Estrogênio/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Trastuzumab , Células Tumorais Cultivadas
12.
Med Oncol ; 25(2): 113-24, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17973095

RESUMO

Estrogen has been implicated in promoting breast cancer in a majority of women. Endocrine therapy controlling estrogen production has been the guiding principle in treating breast cancer for more than a century. A greater understanding of this disease at a molecular level has led to the development of molecules that inhibit estrogen production by inhibiting the aromatase enzyme, that is the primary source of estrogen in postmenopausal women. This review examines the evolution of aromatase inhibitor (AI) based therapies over the past three decades. The third generation aromatase inhibitors (anastrozole, letrozole and exemestane), which have been found to be extremely specific and effective in an adjuvant/neoadjuvant/extended adjuvant setting are discussed from a biochemical and clinical perspective. A comprehensive discussion of the past, present, and future of aromatase inhibitors is conducted in this review.


Assuntos
Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Aminoglutetimida/uso terapêutico , Androstadienos/uso terapêutico , Androstenodiona/análogos & derivados , Androstenodiona/uso terapêutico , Inibidores da Aromatase/farmacologia , Ensaios Clínicos como Assunto , Fadrozol/uso terapêutico , Feminino , Humanos , Letrozol , Nitrilas/uso terapêutico , Triazóis/uso terapêutico
13.
Steroids ; 72(8): 666-71, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17588628

RESUMO

Currently available radioimmunoassay methods for estradiol in serum lack sufficient sensitivity and precision to monitor estradiol levels in patients placed on third generation aromatase inhibitors. We recently validated a gas chromatography/tandem mass spectrometry assay (GC/MS/MS) for estradiol and determined estrogen levels in normal post-menopausal women and in women with breast cancer before and during administration of aromatase inhibitors. Validation of the GC/MS/MS assay in human plasma and human serum included determination of assay sensitivity (<0.63 pg/ml), precision (all CVs less than 17.8%), recovery (98-103%), and linearity of recovery (R=0.998). Levels of estradiol were lower when assayed by GC/MS/MS compared to RIA under all conditions (7.26+/-4.82 pg/ml versus 11.9+12.0 pg/ml in normal post-menopausal women; 5.88+/-3.43 pg/ml versus 13.8+/-7.5 pg/ml in breast cancer patients prior to treatment; and<0.63 pg/ml versus 5.8+/-4.1 pg/ml during aromatase inhibitor therapy). Fifty-five women treated either with atamestane/toremiphene or letrozole/placebo were monitored for estradiol levels at 4, 8 and 12 weeks of therapy. The mean levels of estradiol during aromatase inhibitor therapy was 5.8+/-4.1 pg/ml as measured by RIA and <0.63 pg/ml by GC/MS/MS. The degree of suppression with the aromatase inhibitors as detected by RIA was 58% versus >89% by GC/MS. These results suggest that most RIA methods detect cross-reacting estrogen metabolites and yield higher measured levels than GC/MS/MS. Several pharmacological and clinical considerations suggest that GC/MS/MS should become the preferred method for monitoring aromatase inhibitor therapy.


Assuntos
Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Estradiol/sangue , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas em Tandem , Androstenodiona/análogos & derivados , Androstenodiona/uso terapêutico , Bioensaio , Neoplasias da Mama/sangue , Feminino , Humanos , Letrozol , Nitrilas/uso terapêutico , Placebos , Pós-Menopausa , Radioimunoensaio , Sensibilidade e Especificidade , Triazóis/uso terapêutico
14.
Clin Cancer Res ; 13(9): 2751-7, 2007 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17473209

RESUMO

PURPOSE: Aromatase inhibitors that block the synthesis of estrogen are proving to be superior to antiestrogens and may replace tamoxifen as first-line treatment for postmenopausal estrogen receptor (ER)-positive breast cancer patients. However, acquisition of resistance to all forms of treatments is inevitable and a major clinical concern. In this study, we have investigated the effects of long-term estrogen deprivation in the breast cancer xenograft model and whether sensitivity to antiestrogens can be restored in vivo. We also compared whether combining wortmannin with tamoxifen or fulvestrant inhibited tumor growth better than either drug alone. EXPERIMENTAL DESIGN: Long-term estrogen-deprived aromatase-transfected human ER-positive breast cancer cells (UMB-1Ca) were grown as tumors in ovariectomized athymic nude mice. Twelve weeks after inoculation, when tumors reached 300 mm(3), animals were grouped and injected with vehicle, Delta(4)A, letrozole, tamoxifen, fulvestrant, wortmannin, tamoxifen plus wortmannin, and wortmannin plus fulvestrant. Tumor volumes were measured weekly. RESULTS: Tumors of UMB-1Ca cells grew equally well with and without androstenedione, indicating the ability of the cells to proliferate in the absence of estrogen. The combination of wortmannin with tamoxifen or fulvestrant inhibited tumor growth better than either drug alone. The combination of wortmannin plus fulvestrant was the most effective treatment that maintained tumor regression for a prolonged time. CONCLUSION: These results suggest that blocking both ER and growth factor receptor pathways could provide effective control over tumor growth of long-term estrogen-deprived human breast cancers.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Moduladores de Receptor Estrogênico/uso terapêutico , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Androstadienos/uso terapêutico , Androstenodiona/uso terapêutico , Animais , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/enzimologia , Linhagem Celular Tumoral , Receptor alfa de Estrogênio/metabolismo , Humanos , Letrozol , Camundongos , Camundongos Nus , Nitrilas/uso terapêutico , Tamoxifeno/uso terapêutico , Triazóis/uso terapêutico , Wortmanina
15.
Planta Med ; 73(4): 318-22, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17354167

RESUMO

Non-steroidal as well as steroidal aromatase inhibitors are currently being discussed as alternatives to tamoxifen in the first-line treatment of patients with hormone-dependent breast cancer. Many of these women are in a postmenopausal state and additionally troubled by climacteric complaints. Naturally occurring symptoms like hot flushes and night sweats can be triggered or augmented by anti-hormonal drugs. At the aromatase molecule, steroidal inhibitors like exemestane and formestane compete with the hormonal precursors for the substrate binding site and inactivate the enzyme irreversibly. An isopropanolic extract of the rootstock of black cohosh (iCR), which is a common comedication of aromatase inhibitors in breast cancer patients suffering from climacteric symptoms, contains triterpene glycosides and cinnamic acid esters, both of which possess structural similarities to steroids. We therefore tested a high dose of iCR, guaranteeing an effective uptake of 60 mg herbal substance per kg body weight and shown to influence rat bone and uterus, for putative interactions with two low dosing regimens of 3.5 mg or 5.0 mg formestane per animal and day. We chose a rat model of chemically induced breast cancer and evaluated tumor growth and serum estrogen levels. Compared to a tumor area of 1400 mm2 after 21 days of unopposed tumor growth, formestane treatment, irrespective of concomitant black cohosh application, significantly reduced neoplastic growth by 50%. Formestane also significantly reduced serum estrogen levels, an effect which was also not abolished by iCR. Therefore, in this experimental setting, when challenging two low doses of formestane with a high dose of iCR, our data do not raise concerns against combining aromatase inhibitors with black cohosh.


Assuntos
Androstenodiona/análogos & derivados , Antineoplásicos Fitogênicos/farmacologia , Inibidores da Aromatase/farmacologia , Cimicifuga , Fitoterapia , Extratos Vegetais/farmacologia , 9,10-Dimetil-1,2-benzantraceno , Androstenodiona/administração & dosagem , Androstenodiona/farmacologia , Androstenodiona/uso terapêutico , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/uso terapêutico , Inibidores da Aromatase/administração & dosagem , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/sangue , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral/efeitos dos fármacos , Quimioterapia Combinada , Estradiol/sangue , Feminino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Ratos , Ratos Sprague-Dawley
16.
J Natl Cancer Inst ; 98(18): 1285-91, 2006 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-16985247

RESUMO

BACKGROUND: Aromatase inhibitors and inactivators have been extensively tested in patients with advanced breast cancer, but it is unclear whether they offer any survival benefits compared with standard hormonal treatment with tamoxifen or progestagens. We performed a meta-analysis of randomized controlled trials that compared several generations of aromatase inhibitors and inactivators with standard hormonal treatment in patients with advanced breast cancer. METHODS: The endpoint that we assessed was survival. Trials were located through searches of PubMed and Cochrane Library (last update March 2006). Relative hazards (RHs) were summarized across trials through fixed- and random-effects analyses, and heterogeneity was assessed with the Q and I2 statistics. All statistical tests were two-sided. RESULTS: Twenty-five different comparisons, with a total of 8504 patients, were included in the meta-analysis. We found statistically significant survival benefits with third-generation aromatase inhibitors and inactivators (vorozole, letrozole, examestane, and anastrazole) (RH = 0.87, 95% confidence interval [CI] = 0.82 to 0.93; P<.001) but not with first-generation (aminoglutethimide) or second-generation (formestane and fadrozole) agents. The difference in the summary effects between these two groups of trials was statistically significant (P = .04). The survival benefit with third-generation agents in first-line trials, in which these agents were compared with tamoxifen (11% RH reduction, 95% CI = 1% to 19%; P = .03), was identical to their benefit in second- and subsequent-line trials in which these agents were compared with other treatments (14% RH reduction, 95% CI = 6% to 21%; P<.001). CONCLUSIONS: Inhibition of the aromatase system, in particular with third-generation aromatase inhibitors and inactivators, appears to be associated with statistically significant improved survival of patients with advanced breast cancer compared with standard hormonal treatments.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias Hormônio-Dependentes/mortalidade , Adulto , Idoso , Aminoglutetimida/uso terapêutico , Anastrozol , Androstenodiona/análogos & derivados , Androstenodiona/uso terapêutico , Neoplasias da Mama/patologia , Fadrozol/uso terapêutico , Feminino , Humanos , Letrozol , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Hormônio-Dependentes/patologia , Nitrilas/uso terapêutico , Razão de Chances , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida , Triazóis/uso terapêutico
17.
Cancer Res ; 65(24): 11287-91, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16357134

RESUMO

Lung cancer is the most common cancer in the world. It is a highly lethal disease in women and men, and new treatments are urgently needed. Previous studies implicated a role of estrogens and estrogen receptors in lung cancer progression, and this steroidal growth-stimulatory pathway may be promoted by tumor expression and activity of aromatase, an estrogen synthase. We found expression of aromatase transcripts and protein in human non-small cell lung cancer (NSCLC) cells using reverse transcription-PCR and Western immunoblots, respectively. Aromatase staining by immunohistochemistry was detected in 86% of archival NSCLC tumor specimens from the clinic. Further, biological activity of aromatase was determined in NSCLC tumors using radiolabeled substrate assays as well as measure of estradiol product using ELISA. Significant activity of aromatase occurred in human NSCLC tumors, with enhanced levels in tumor cells compared with that in nearby normal cells. Lung tumor aromatase activity was inhibited by anastrozole, an aromatase inhibitor, and treatment of tumor cells in vitro with anastrozole led to significant suppression of tumor cell growth. Similarly, among ovariectomized nude mice with A549 lung tumor xenografts, administration of anastrozole by p.o. gavage for 21 days elicited pronounced inhibition of tumor growth in vivo. These findings show that aromatase is present and biologically active in human NSCLCs and that tumor growth can be down-regulated by specific inhibition of aromatase. This work may lead to development of new treatment options for patients afflicted with NSCLC.


Assuntos
Inibidores da Aromatase/uso terapêutico , Aromatase/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Nitrilas/uso terapêutico , Triazóis/uso terapêutico , Anastrozol , Androstenodiona/uso terapêutico , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Immunoblotting , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Nus , Ovariectomia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Heterólogo
18.
J Clin Endocrinol Metab ; 90(2): 855-63, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15522925

RESUMO

Previous studies of Delta 4-androstene-3,17-dione (4-androstenedione) administration in men have not demonstrated sustained increments in testosterone levels, fat-free mass (FFM), and muscle strength, and failure to demonstrate androstenedione's androgenic/anabolic effects has stifled efforts to regulate its sales. To determine whether 4-androstenedione has androgenic/anabolic properties, we evaluated its association with androgen receptor (AR) and its effects on myogenesis in vitro. Additionally, we studied the effects of a high dose of 4-androstenedione on testosterone levels, FFM, and muscle strength in hypogonadal men. We determined the dissociation constant (K(d)) for 4-androstenedione using fluorescence anisotropy measurement of competitive displacement of fluorescent androgen from AR ligand-binding domain. AR nuclear translocation and myogenic activity of androstenedione were evaluated in mesenchymal, pluripotent C3H10T1/2 cells, in which androgens stimulate myogenesis through an AR pathway. We determined effects of a high dose of androstenedione (500 mg thrice daily) given for 12 wk on FFM, muscle strength, and hormone levels in nine healthy, hypogonadal men. 4-Androstenedione competitively displaced fluorescent androgen from AR ligand-binding domain with a lower affinity than dihydrotestosterone (K(d), 648 +/- 21 and 10 +/- 0.4 nm, respectively). In C3H10T1/2 cells, 4-androstenedione caused nuclear translocation of AR and stimulated myogenesis, as indicated by a dose-dependent increase in myosin heavy chain II+ myotube area and up-regulation of MyoD protein. Stimulatory effects of 4-androstenedione on myosin heavy chain II+ myotubes and myogenic determination factor expression were attenuated by bicalutamide, an AR antagonist. Administration of 1500 mg 4-androstenedione daily to hypogonadal men significantly increased serum androstenedione, total and free testosterone, estradiol, and estrone levels and suppressed SHBG and high-density lipoprotein cholesterol levels. 4-androstenedione administration was associated with significant gains in FFM (+1.7 +/- 0.5 kg; P = 0.012) and muscle strength in bench press (+4.3 +/- 3.1 kg; P = 0.006) and leg press exercises (+18.8 +/- 17.3 kg; P = 0.045). 4-androstenedione is an androgen that binds AR, induces AR nuclear translocation, and promotes myogenesis in vitro, with substantially lower potency than dihydrotestosterone. 4-androstenedione administration in high doses to hypogonadal men increases testosterone levels, FFM, and muscle strength, although at the dose tested, the anabolic effects in hypogonadal men are likely because of its conversion to testosterone.


Assuntos
Androstenodiona/uso terapêutico , Hipogonadismo/fisiopatologia , Músculo Esquelético/fisiopatologia , Receptores Androgênicos/metabolismo , Testosterona/sangue , Células 3T3 , Adulto , Androstenodiona/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Humanos , Hipogonadismo/classificação , Hipogonadismo/tratamento farmacológico , Cinética , Ligantes , Masculino , Camundongos , Pessoa de Meia-Idade , Músculo Esquelético/efeitos dos fármacos , Valores de Referência
19.
Biomed Pharmacother ; 58(4): 255-9, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15183852

RESUMO

In postmenopausal patients, estrogens have an important role in breast cancer growth and aromatase inhibitors (AI) suppress the aromatase enzyme system which converts androgens into estrogens. The aim of this study was to evaluate the effect on estrogen suppression of formestane 250 mg i.m. fortnightly, given immediately after the failure of a previous treatment with non-steroidal AI. Twenty-two advanced breast cancer patients progressing on letrozole, anastrozole and aminoglutethimide entered the study. At the beginning of the study, the serum estrogen levels were suppressed by the previous treatment with non-steroidal AI, and the following treatment with formestane moderately maintained this suppression; in four patients serum estrogen levels increased fivefold after 10 weeks. Neither complete nor partial responses were observed; 11 patients (50%) showed a stable disease lasting > or = 6 months, and the median time to progression was 6 months (range 3-9 months). No correlation was observed between clinical responses and serum estrogen suppression. Tolerability was satisfactory, and no patient withdrew from the study due to adverse events. In conclusion, formestane has demonstrated a moderate activity in estrogen suppression, and there is evidence that, at the failure of a previous treatment with non-steroidal AI, the sequential use of steroidal AI is feasible. This approach can be used in clinical practice in order to offer a disease control with a satisfactory quality of life.


Assuntos
Androstenodiona/análogos & derivados , Androstenodiona/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Estradiol/sangue , Antagonistas de Estrogênios/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Androstenodiona/efeitos adversos , Androstenodiona/farmacologia , Antineoplásicos Hormonais/efeitos adversos , Antineoplásicos Hormonais/farmacologia , Inibidores da Aromatase , Antagonistas de Estrogênios/farmacologia , Feminino , Humanos , Injeções Intramusculares , Pessoa de Meia-Idade , Pós-Menopausa , Receptores de Estradiol/metabolismo
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