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1.
Ann Oncol ; 18(4): 694-700, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17301072

RESUMO

BACKGROUND: The purpose was to investigate adjuvant marrow-supportive high-dose chemotherapy compared with an equitoxicity-tailored comparator arm. PATIENTS AND METHODS: Five hundred and twenty-five women below the age of 60 years with operated high-risk primary breast cancer were randomised to nine cycles of granulocyte colony-stimulating factor supported and individually tailored FEC (5-fluorouracil, epirubicin, cyclophosphamide), (n = 251) or standard FEC followed by marrow-supported high-dose therapy with CTCb (cyclophosphamide, thiotepa, carboplatin) therapy (n = 274), followed by locoregional radiotherapy and tamoxifen for 5 years. RESULTS: There were 104 breast cancer relapses in the tailored FEC group versus 139 in the CTCb group (double triangular method by Whitehead, P = 0.046), with a median follow-up of all included patients of 60.8 months. The event-free survival demonstrated 121 and 150 events in the tailored FEC- and CTCb group, respectively [P = 0.074, hazard ratio (HR) 0.804, 95% confidence interval (CI) 0.633-1.022]. Ten patients in the tailored FEC regimen developed acute myeloid leukaemia (AML)/myelodysplasia (MDS). One hundred deaths occurred in the tailored FEC group and 121 in the CTCb group (P = 0.287, HR 0.866, 95% CI 0.665-1.129). CONCLUSION: The update of this study shows an improved outcome linked to the tailored FEC treatment in relation to breast cancer relapse, but also an increased incidence of AML/MDS.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/mortalidade , Carboplatina/administração & dosagem , Ciclofosfamida/administração & dosagem , Epirubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Tiotepa/administração & dosagem
2.
Breast Cancer Res Treat ; 67(2): 111-6, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11519859

RESUMO

Estrogens administered in high doses were commonly used for therapy of advanced breast cancer before the introduction of contemporary endocrine therapy. While the mechanism of the antitumor effect is unknown, in vitro investigations have shown estrogens in high concentrations to be toxic to cell growth. Further, it has been shown that exposure of MCF-7 cells to estrogens in low concentrations may enhance the sensitivity and also lower the toxicity threshold to estrogens. This study was designed to evaluate treatment with diethylstilbestrol (DES) in postmenopausal women with advanced breast cancer becoming resistant to estrogen deprivation. Thirty-two patients with advanced breast cancer previously exposed to multiple endocrine treatment regimens (median 4, range 2-10) were enrolled. Their tumor should have revealed evidence of endocrine sensitivity (previous partial response or at least stable disease for > or = 6 months to therapy). Each patient received DES 5 mg t.i.d. Four patients terminated therapy after < or = 2 weeks on therapy due to side effects; another two patients terminated therapy before progression for similar reasons (one patient after SD for 15 weeks and one with a PR after 39 weeks). Four patients obtained CR and six patients PR. In addition, two patients had SD for > or = 6 months duration. Five patients had an objective response and one patient a SD lasting for > or = 1 year. Our results reveal estrogens administered in high doses may have antitumor effects in breast cancer patients heavily pretreated with endocrine therapy. Such treatment represents a valuable alternative to chemotherapy in selected patients.


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/tratamento farmacológico , Dietilestilbestrol/farmacologia , Estrogênios não Esteroides/farmacologia , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Resultado do Tratamento
3.
Br J Cancer ; 85(2): 147-51, 2001 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-11461068

RESUMO

Alterations in the insulin-like growth factor (IGF)-system were evaluated in 16 patients treated with diethylstilboestrol 5 mg 3 times daily. Fasting blood samples were obtained before treatment and after 2 weeks, 1 month and/or 2-3 months on therapy. Insulin-like growth factor (IGF)-I, IGF-II, free IGF-I, IGF-binding protein (IGFBP)-1, IGFBP-2 and IGFBP-3 were measured by radioimmuno-/immunoradiometric-assays. All samples were subjected to Western ligand blotting as well as immunoblotting for IGFBP-3. We observed a significant decrease (percentage of pretreatment levels with 95 confidence intervals of the mean) in IGF-I [2 weeks 63% (49-79); 1 month 56% (44-73); 2-3 months 66% (53-82)], IGF-II [2 weeks 67% (56-80); 1 month 60% (52-68); 2-3 months 64% (55-75)], free IGF-I [2 weeks 29% (19-42); 1 month 25% (18-36); 2-3 months 31% (21-46)], IGFBP-2 [2 weeks 53% (18-156); 1 month 69% (61-78); 2-3 months 66% (57-78)], IGFBP-3 [2 weeks 74% (63-85); 1 month 69% (62-76); 2-3 months 71% (63-80)], as well as IGFBP-3 protease activity [2 weeks 71% (54-95); 1 month 78% (64-94); 2-3 months 71% (54-93)]. Contrary, the plasma levels (percentage of pretreatment levels with 95 confidence intervals of the mean) of IGFBP-1 [2 weeks 250% (127-495); 1 month 173% (138-542); 2-3 months 273% (146-510)] and IGFBP-4 [2 weeks 146% (112-192); 1 month 140% (116-169); 2-3 months 150% (114-198)] increased significantly. While this study confirms previous observations during treatment with oral oestrogens in substitution doses, the reduction in plasma IGF-II, free IGF-I, IGFBP-2 and -3 are all novel findings. A profound decrease in free IGF-I suggests a reduced bioavailability of IGFs from plasma to the tissues. These observations may be of significance to understand the mechanisms of the antitumour effect of diethylstilboestrol in pharmacological doses.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Dietilestilbestrol/uso terapêutico , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Radioimunoensaio
4.
Lancet ; 356(9239): 1384-91, 2000 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-11052580

RESUMO

BACKGROUND: Chemotherapy drug distribution varies greatly among individual patients. Therefore, we developed an individualised fluorouracil, epirubicin, cyclophosphamide (FEC) regimen to improve outcomes in patients with high-risk early breast cancer. We then did a randomised trial to compare this individually tailored FEC regimen with conventional adjuvant chemotherapy followed by consolidation with high-dose chemotherapy with stem-cell support. METHODS: 525 women younger than 60 years of age with high-risk primary breast cancer were randomised after surgery to receive nine cycles of tailored FEC to haematological equitoxicity with granulocyte colony-stimulating factor (G-CSF) support (n=251), or three cycles of FEC at standard doses followed by high-dose chemotherapy with cyclophosphamide, thiotepa, and carboplatin (CTCb), and peripheral-blood stem-cell or bone-marrow support (n=274). Both groups received locoregional radiation therapy and tamoxifen for 5 years. The primary outcome measure was relapse-free survival, and analysis was by intention to treat. FINDINGS: At a median follow-up of 34.3 months, there were 81 breast-cancer relapses in the tailored FEC group versus 113 in the CTCb group (double triangular method p=0.04). 60 deaths occurred in the tailored FEC group and 82 in the CTCb group (log-rank p=0.12). Patients in the CTCb group experienced more grade 3 or 4 acute toxicity compared with the tailored FEC group (p<0.0001). Two treatment-related deaths (0.7%) occurred in the CTCb group. Six patients in the tailored FEC group developed acute myeloid leukaemia and three developed myelodysplastic syndrome. INTERPRETATION: Tailored FEC with G-CSF support resulted in a significantly improved relapse-free survival and fewer grade 3 and 4 toxicities compared with marrow-supported high-dose chemotherapy with CTCb as adjuvant therapy of women with high-risk primary breast cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Doença Aguda , Adulto , Algoritmos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Quimioterapia Adjuvante , Terapia Combinada , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Intervalo Livre de Doença , Epirubicina/administração & dosagem , Epirubicina/efeitos adversos , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Humanos , Infusões Intravenosas , Leucemia Mieloide/induzido quimicamente , Metástase Linfática , Mastectomia Segmentar , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Suécia , Tiotepa/administração & dosagem , Tiotepa/efeitos adversos
5.
Eur J Cancer ; 36(8): 976-82, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10885600

RESUMO

This phase II, multicentre, open-label, clinical trial evaluated antitumoral efficacy, tolerability and endocrine effects following 25 mg of treatment with oral exemestane given daily to postmenopausal women with metastatic breast cancer. Eligibility criteria included oestrogen and/or progesterone positivity or a prior response to hormonal therapy if receptor status was unknown; prior failure to tamoxifen therapy; and progressive disease. Patients were divided into three strata: patients who did not respond to tamoxifen or progressed after disease stabilisation (SD) for less than 6 months (stratum 1); patients who, after an initial response or SD lasting at least 6 months, experienced disease progression whilst on tamoxifen (stratum 2); patients with recurrent metastatic disease during or within 12 months of discontinuing adjuvant tamoxifen (stratum 3). Of the 137 patients who received exemestane, 4 experienced a complete response (CR) and 28 a partial response (PR), for an overall response rate of 23%. Another 33 patients had SD for > or = 24 weeks, resulting in an overall success rate of 47%. The median time to objective response was 16.1 weeks (95% confidence interval (CI) 9.9-24.1). The median response duration was 69.4 weeks, the median duration of overall success 59.1 weeks, the median time to progression (TTP) 25.1 weeks and the median time to treatment failure (TTF) 24 weeks. Response to previous hormonal therapy had little effect on the results, except that there was a trend toward a higher overall success rate in patients who did not respond to previous hormonal therapy. After 8 weeks of therapy, serum levels of oestradiol (E2), oestrone (E1) and oestrone sulphate (E1S) were suppressed to 15.2%, 9.7% and 10.7% of baseline, respectively. The most common adverse events of drug-related or indeterminate cause were hot flushes (14%), dizziness (9%), nausea (8%) and increased sweating (5%). Exemestane had a favourable effect on performance status and tumour-related signs and symptoms, both of which improved or stabilised in approximately 67% and 68% of patients respectively. Exemestane is a unique therapy that is highly active and well tolerated as a new treatment for women with metastatic breast cancer.


Assuntos
Androstadienos/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Tamoxifeno/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Aromatase , Neoplasias da Mama/sangue , Estrogênios/sangue , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Pós-Menopausa , Falha de Tratamento
6.
Zentralbl Chir ; 125(12): 947-53, 2000.
Artigo em Alemão | MEDLINE | ID: mdl-11190611

RESUMO

BACKGROUND: Different approaches for an effective quality management are funded by the Ministry of health to verify, and if necessary to optimize, the quality of health care using the tracer diagnosis breast, rectal and lung cancer in 8 regions in Germany. The aim of the study is to develop a model for description and support of high quality health care for cancer patients. The conception, initial findings and inter-hospital variations are shown for some aspects of the primary therapy of rectal cancer in the region of Munich (population 2.3 million). PATIENTS AND METHODS: The field study is a population based cohort study. The recruitment phase started in April 1996 and finished March 1998. Established documentation sheets of the tumor registry along with original reports (reports of the doctors, pathologists etc.) are used for documentation. RESULTS: 26 surgical departments, 12 pathology departments, 9 radiotherapy departments and about 300 general practitioners have documented for this study. So far a sample of 809 have been analyzed. After an almost complete documentation the crude incidence will be about 23/100.000. 57% of all patients were men and 43% were women. 765 patients have been operated, 44 not. PT-categories (for the operated patients) are distributed as follows: pTis and pT1 10.7%, pT2 25%, pT3 54.5%, pT4 9.8%. Distribution of tumor localization: < 4 cm 6.7%, 4 bis < 8 cm 36.2%, 8 bis < 12 cm 30.8%, > or = 12 cm 26.3%. Local excision was performed in 4%, sphincter conserving therapy (SCT) in 71.5% (protective stoma: 23.7%), not sphincter conserving therapy (nSCT) in 18.4% and a palliative operation in 6%. The large surgical departments (> 25 patients per year) treated 53.8% of all patients. The proportion of older patients is significant higher in the smaller departments (< 10 patients per year). There are no differences in pTNM-distribution. No variations exist in the operation method between the department groups. More or less varying inter-hospital differences exist between the individual departments for all epidemiological and therapeutical parameters. CONCLUSIONS: Variations of medical care exist more between the individual hospitals than between department groups, divided by workload. To support the quality of health care a feedback of the results has to be available for each physician and each department.


Assuntos
Avaliação de Processos e Resultados em Cuidados de Saúde , Neoplasias Retais/cirurgia , Gestão da Qualidade Total , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Masculino , Estadiamento de Neoplasias , Cuidados Paliativos , Qualidade de Vida , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Taxa de Sobrevida
7.
Cancer Lett ; 145(1-2): 73-7, 1999 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-10530772

RESUMO

Adjuvant treatment of breast cancer with tamoxifen may be associated with reduced risk of cardiovascular disease. Serum homocysteine level has been suggested to be a risk factor for cardiovascular disease influenced by estrogenic hormones. We evaluated a subset of postmenopausal women who had participated in a longitudinal, double-blind, randomized, placebo-controlled toxicity study of tamoxifen 10 mg orally, twice daily. Twenty-seven treated subjects and 37 placebo subjects had measurements of serum homocysteine levels made on previously frozen samples obtained at baseline and after 12 months. After treatment with tamoxifen, we found lower levels of serum homocysteine of borderline statistical significance.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Homocisteína/sangue , Pós-Menopausa/sangue , Tamoxifeno/uso terapêutico , Administração Oral , Neoplasias da Mama/sangue , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Modelos Lineares , Pessoa de Meia-Idade , Fatores de Risco
8.
Clin Chem ; 45(2): 252-6, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9931048

RESUMO

In this study, we evaluated the effect of estrogen suppression with three aromatase inhibitors, aminoglutethimide (n = 30), formestane (n = 12), and exemestane (n = 10), and the progestin megestrol acetate (n = 21) on plasma total homocysteine (tHcy) in patients suffering from advanced breast cancer. Treatment with 1 g/day aminoglutethimide for 2 and 3-5 months increased plasma tHcy by a mean value of 24.5% [95% confidence interval, 10.5-40.4%] at 2 months and 35.8% (95% confidence interval, 18.2-55.9%) at 3-5 months, corresponding to increases in the mean plasma tHcy of 1.90 and 3.67 micromol/L, respectively. In contrast, none of the other treatment options influenced plasma tHcy concentrations. The finding that aminoglutethimide, but none of the other aromatase inhibitors or megestrol acetate, influenced plasma tHcy suggests that this effect is achieved by mechanisms not related to suppression of plasma estrogens or to the glucocorticoids administered in concert.


Assuntos
Inibidores da Aromatase , Neoplasias da Mama/sangue , Inibidores Enzimáticos/uso terapêutico , Antagonistas de Estrogênios/uso terapêutico , Homocisteína/sangue , Pós-Menopausa , Aminoglutetimida/uso terapêutico , Androstadienos/uso terapêutico , Androstenodiona/análogos & derivados , Androstenodiona/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Creatinina/sangue , Humanos , Vitaminas/sangue
10.
Clin Cancer Res ; 4(9): 2089-93, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9748124

RESUMO

The effect of exemestane (6-methylenandrosta-1,4-diene-3,17-dione) 25 mg p.o. once daily on in vivo aromatization was studied in 10 postmenopausal women with advanced breast cancer. Aromatization was determined before treatment and after 6-8 weeks on therapy by administering a bolus injection of [3H]androstenedione (500 microCi) and [14C]estrone (5 microCi) followed by measurement of the isotope ratio of urinary estrogens after high-performance liquid chromatography purification. In addition, plasma endogenous estrogens were measured with highly sensitive radioimmunoassays after separation with high-performance liquid chromatography. Treatment with exemestane suppressed whole body aromatization from a mean pretreatment value of 2.059% to 0.042% (mean suppression of 97.9%). Plasma levels of estrone, estradiol, and estrone sulfate were found to be suppressed by 94.5%, 92.2%, and 93.2%, respectively. This is the first study revealing near total aromatase inhibition in vivo with the use of a steroidal aromatase inhibitor. The observation that exemestane is a highly potent aromatase inhibitor, together with the fact that the drug is administered p.o. and causes limited side effects, suggests that exemestane is a promising new drug for the treatment of hormone sensitive breast cancer.


Assuntos
Androstadienos/uso terapêutico , Antineoplásicos/uso terapêutico , Inibidores da Aromatase , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Administração Oral , Androstenodiona/metabolismo , Aromatase/metabolismo , Radioisótopos de Carbono , Estradiol/sangue , Estradiol/metabolismo , Estrogênios/sangue , Estrogênios/urina , Estrona/análogos & derivados , Estrona/sangue , Estrona/metabolismo , Feminino , Humanos , Pós-Menopausa , Trítio
11.
Ann Oncol ; 9(4): 403-11, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9636831

RESUMO

BACKGROUND: Conventional dosages of cytostatics in mg/m2 will cause marked variations in systemic exposure, resulting in over- and under-treatment, at least with respect to side effects. PATIENTS AND METHODS: We are conducting a randomized adjuvant study for breast cancer patients younger than 60 years of age with > or = 70% risk of recurrence within five years. The first 89 consecutive patients who have received nine courses q three weeks of individually dose-escalated and G-CSF (filgrastim)-supported FEC (5-fluorouracil (5-FU), epirubicin, and cyclophosphamide) therapy given with ciprofloxacin prophylaxis were included in this analysis. Six different FEC dose levels were used for treatment at equivalent haematological toxicity. Dose modifications were based on white blood cell and platelet counts on days 8, 11/12, 15, and 22. RESULTS: Eighty-three of 89 patients completed all nine courses. The median epirubicin and cyclophosphamide doses were 782 mg/m2 (range 0-994 mg/m2) and 10.330 mg/m2 (range 0-14.460 mg/m2), respectively. Patients treated at the two highest dose levels experienced NCl grade 0 or 1 toxicities in 73% to 92% of the courses. Three patients have developed acute myeloid leukaemia, and two of them have demonstrated abnormalities compatible with topoisomerase II-poison-related karyotypic changes. CONCLUSIONS: Tailored adjuvant G-CSF-supported FEC polychemotherapy will make it possible for all patients to be treated at equivalent levels of haematological toxicity with significantly higher doses without a marked increase in other organ toxicities.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Doenças Hematológicas/prevenção & controle , Idoso , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Relação Dose-Resposta a Droga , Esquema de Medicação , Epirubicina/administração & dosagem , Feminino , Filgrastim , Fluoruracila/administração & dosagem , Doenças Hematológicas/induzido quimicamente , Humanos , Mastectomia Radical , Pessoa de Meia-Idade , Prognóstico , Proteínas Recombinantes , Resultado do Tratamento
12.
Maturitas ; 28(3): 259-65, 1998 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-9571602

RESUMO

OBJECTIVES: To evaluate the effects of endogenous estrogens and progestins on the IGF-system during the normal menstrual cycle in healthy premenopausal women not using contraceptive drugs. METHODS: Nine women had fasting blood samples obtained at 2-3 days intervals during a 5 week study period. Plasma levels of IGF-I, IGF-II, IGFBP-I, IGFBP-3, estradiol and progesterone were measured by radioimmunoassay (RIA) in each sample. IGFBP-3 was also evaluated by Western ligand blot (WLB) and immunoblot. Any differences between the menstrual phase (defined as day 1-5), follicular and luteal phases (separation based on plasma estradiol and progesterone values) were evaluated by the Friedman test. RESULTS: A small but significant difference in plasma levels of IGF-I (P < 0.01) and IGFBP-d (P < 0.05) measured by RIA between the three phases were seen with the highest levels found during the follicular phase. No change in plasma levels of IGFBP-1 and IGF-II was found and immunoblots did not reveal any alteration in the ratio of fragmented to intact IGFBP-3 during the menstrual cycle. A positive correlation between plasma levels of IGF-I and estradiol was seen in 8 out of 9 patients (P = 0.012). CONCLUSIONS: The finding of a slight but significant higher level of plasma IGF-I in the follicular and luteal phases compared with the menstrual phase suggests plasma estradiol may influence the level of this growth factor. This hypothesis is further supported by the finding of a correlation between plasma levels of IGF-I and estradiol but not progesterone in individual patients at different times during the menstrual cycle.


Assuntos
Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like II/análise , Fator de Crescimento Insulin-Like I/análise , Ciclo Menstrual/metabolismo , Pré-Menopausa/metabolismo , Adulto , Estradiol/sangue , Estradiol/metabolismo , Feminino , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Ciclo Menstrual/sangue , Pessoa de Meia-Idade , Pré-Menopausa/sangue , Progesterona/sangue , Progesterona/metabolismo , Radioimunoensaio
13.
Scand J Clin Lab Invest ; 58(2): 103-7, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9587161

RESUMO

Thyroid function was evaluation in 26 postmenopausal women with breast cancer before and at various time intervals during treatment with tamoxifen. Tamoxifen treatment suppressed plasma levels of FT3 and FT4 (p < 0.005 for both) and elevated plasma concentrations of TBG (p < 0.005 and TG (p < 0.025). In general, these changes became significant after 6 months of treatment. Plasma TSH increased significantly after 1 y of treatment (p < 0.025). A fall in FT4 and FT3 combined with increase in TSH suggests a reduced bioavailability of T4 and T3 during tamoxifen treatment. The increase in TG may reflect a reduced synthesis or liberation of T4 resulting in a reduced plasma level of FT4. Our findings suggest that tamoxifen influences the thyroid hormone levels, not only by modulating plasma TBG, but also by interfering with hormone synthesis or secretion in the thyroid gland.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Pós-Menopausa/efeitos dos fármacos , Tamoxifeno/uso terapêutico , Testes de Função Tireóidea , Glândula Tireoide/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Feminino , Humanos , Pessoa de Meia-Idade , Tireoglobulina/sangue , Tireoglobulina/efeitos dos fármacos , Glândula Tireoide/fisiologia , Tireotropina/sangue , Tireotropina/efeitos dos fármacos , Tiroxina/sangue , Tiroxina/efeitos dos fármacos , Proteínas de Ligação a Tiroxina/efeitos dos fármacos , Proteínas de Ligação a Tiroxina/metabolismo , Tri-Iodotironina/sangue , Tri-Iodotironina/efeitos dos fármacos
16.
Eur J Cancer ; 32A(5): 789-92, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-9081355

RESUMO

We studied the clinical and endocrine effects of the aromatase inhibitor formestane (4-hydroxyandrostenedione, 4-OHA) in heavily pretreated breast cancer patients (median number of previous endocrine treatments 2, range 1-4). Of 30 patients eligible for response evaluation, 3 patients (10%) showed a partial response while 11 patients (36.7%) experienced stable disease over a time period of at least 6 months. Plasma levels of oestrone, oestradiol and oestrone sulphate were found suppressed to a mean of 33.9, 35.6 and 24.2% of control values. 4 of 6 patients experienced a further substantial reduction in plasma oestrone sulphate to < 5% of pretreatment values when aminoglutethimide (AG) was added after relapse on 4-OHA monotherapy. Our findings suggest that these aromatase inhibitors may suppress plasma oestrogen levels by a percentage approaching the percentage inhibition of in vivo aromatisation measured by tracer techniques.


Assuntos
Androstenodiona/análogos & derivados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Inibidores da Aromatase , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Aminoglutetimida/administração & dosagem , Androstenodiona/administração & dosagem , Androstenodiona/uso terapêutico , Neoplasias da Mama/sangue , Estrogênios/sangue , Feminino , Humanos , Pessoa de Meia-Idade
17.
J Steroid Biochem Mol Biol ; 57(3-4): 167-71, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8645625

RESUMO

The influence of the novel anti-estrogen droloxifene on the insulin-like growth factor (IGF) system in plasma was studied in two groups of breast cancer patients receiving droloxifene 40 mg o.d. (group 1, n = 6) or 100 mg o.d. (group 2, n = 7). Fasting blood samples were obtained from all patients before treatment and after 3 months (group 1) or 6 months (group 2) on droloxifene treatment, except for two patients in group 2 from whom the second sample was obtained following 2 months on treatment when the drug was to be terminated due to progressive disease. Insulin-like growth factor (IGF)-I, insulin-like growth factor binding protein (IGFBP)-1, IGFBP-3 and pro-IGF-IIE (IGF-IIE) were measured by radioimmunoassay. In patients in group 1, plasma lGF-I levels decreased by a mean value of 20% (P < 0.05) on treatment with droloxifene, while IGFBP-1 increased by a mean value of 45% (P > 0.1). In group 2 we observed a 42% decrease in IGF-I during treatment (P < 0.025), while the level of IGFBP-1 increased by a mean value of 70% (P < 0.025). No significant effect on IGF-IIE or IGFBP-3 was noted in any of the groups. The change in plasma lGF-I and IGFBP-1 observed during treatment with droloxifene resembles what is found in patients treated with tamoxifen. As IGF-I is a potent mitogen for breast cancer cells in vitro, a decrease in the plasma level of this growth factor with an increase in the concentration of IGFBP-1 may contribute to the anti-tumour effects of droloxifene.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/sangue , Antagonistas de Estrogênios/uso terapêutico , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/sangue , Somatomedinas/metabolismo , Tamoxifeno/análogos & derivados , Idoso , Neoplasias da Mama/tratamento farmacológico , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Pessoa de Meia-Idade , Precursores de Proteínas/metabolismo , Tamoxifeno/uso terapêutico
18.
J Steroid Biochem Mol Biol ; 55(2): 229-31, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7495702

RESUMO

We measured the serum levels of tamoxifen and 5 of its metabolites in serum from 7 premenopausal and 9 postmenopausal women during the first 56 days of treatment. The serum levels of N-desdimethyltamoxifen were higher in postmenopausal women compared to premenopausal women (P < 0.02). A similar trend was observed for N-desmethyltamoxifen (P = 0.06).


Assuntos
Antineoplásicos Hormonais/farmacocinética , Neoplasias da Mama/tratamento farmacológico , Pós-Menopausa , Pré-Menopausa , Tamoxifeno/farmacocinética , Adulto , Idoso , Antineoplásicos Hormonais/sangue , Antineoplásicos Hormonais/uso terapêutico , Biotransformação , Neoplasias da Mama/sangue , Feminino , Humanos , Pessoa de Meia-Idade , Tamoxifeno/sangue , Tamoxifeno/uso terapêutico , Fatores de Tempo
19.
J Cell Physiol ; 164(1): 154-63, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7790387

RESUMO

12-hydroxy-eicosatetraenoic acid (12-HETE), the lipoxygenase metabolite of arachidonic acid produced by activated platelets, has been shown to accumulate in peripheral blood mononuclear cells (PBMC) of elderly people. 12-HETE being antimitogenic for lymphocytes, its accumulation in blood cells might be involved in the well-known decline in immune function which accompanies aging. Because HETEs have been shown to be rapidly metabolized and/or incorporated into cellular lipids in a variety of cell types, we have investigated the uptake, metabolism, and intracellular distribution of exogenous 12-HETE by human PBMC. [3H]-12-HETE was dose and time dependently incorporated by PBMC and also metabolized to more polar products. These polar metabolites were mainly released extracellularly and only marginally esterfied in phospholipids. Although [3H]-12-HETE radiolabel was preferentially associated with phosphatidylcholine, especially after prolonged labeling incubations or following successive short labeling pulses, a substantial amount of radiolabel was also found associated with phosphatidylinositol (20-50% of the labeled phospholipids). The stability of 12-HETE in the phospholipid pool was comparable to that reported for most other cell types, with 50% of the initial radiolabel being still present after 18 hr. Upon exposure to mitogenic activation, 12-HETE-labeled PBMC released unmodified 12-HETE from phosphatidylinositol. In addition, 12-HETE dose dependently inhibited the proliferative response of PBMC to Con A stimulation. These results suggest that 12-HETE esterification in phospholipids might lead to the generation of unusual lipid second messengers with impaired capacity to transduce activation signals, thus decreasing lymphocyte function.


Assuntos
Ácidos Hidroxieicosatetraenoicos/metabolismo , Monócitos/citologia , Monócitos/metabolismo , Fosfolipídeos/metabolismo , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico , Divisão Celular , Células Cultivadas , Concanavalina A/farmacologia , Meios de Cultura , Relação Dose-Resposta a Droga , Esterificação , Humanos , Ácidos Hidroxieicosatetraenoicos/farmacocinética , Ácidos Hidroxieicosatetraenoicos/farmacologia , Metabolismo dos Lipídeos , Ativação Linfocitária/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Fatores de Tempo
20.
Ther Drug Monit ; 17(3): 259-65, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7624922

RESUMO

In this assay of the nonsteroidal antiestrogen droloxifene and two metabolites in human serum, the serum samples were deproteinized with an equal volume of acetonitrile and then injected into an analytical octadecylsilane column. The analytical column was equilibrated with acetonitrile/water (1/1, vol/vol) containing acetic acid and diethyl amine and eluted isocratically with 66% acetonitrile in the same buffer. Droloxifene, N-desmethyldroloxifene, and 4-methoxdroloxifene were post-column converted to fluorophors by ultraviolet illumination while passing through a 10-m transparent knitted polytetrafluorethylene reaction coil. Analytical recovery was close to 100%. Within- and between-day precision corresponded to a coefficient of variation (CV) of 2-5% at serum concentrations of > or 25 ng/ml, except for 4-methoxydroloxifene (CV 7-10% at a concentration of 25 ng/ml). By increasing the injection volume from 50 to 250 microliters, the detection limits could be decreased from approximately 5 to 1 ng/ml. Conjugated droloxifene could be estimated in a second run after treatment of sample with an enzyme preparation containing beta-glucuronidase plus sulphatase. The recovery of droloxifene glucuronide was close to 100%. Sulphate conjugates have not been identified and were not accounted for.


Assuntos
Antagonistas de Estrogênios/sangue , Tamoxifeno/análogos & derivados , Cromatografia Líquida de Alta Pressão , Glucuronatos/sangue , Humanos , Tamoxifeno/sangue , Tamoxifeno/metabolismo
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