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2.
Ann Oncol ; 23(11): 2843-2851, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22707751

RESUMO

BACKGROUND: To evaluate whether medullary breast cancer has a better prognosis compared with invasive ductal tumors. METHODS: Among 12,409 patients, 127 were recorded as invasive medullary tumors and 8096 invasive ductal tumors. Medullary and ductal invasive tumors were compared with regard to stage, age at diagnosis, grade, hormone receptor status, peritumoral vascular invasion, and local and systemic treatment. Pattern of relapse, distant recurrence-free interval (DRFI), and overall survival (OS) were determined for both histological groups. Two cohorts were investigated: a full cohort including the pathologist-determined medullary histology without regard to any other tumor features and a cohort restricted to patients with ER-negative grade 3 tumors. RESULTS: Fourteen-year DRFI and OS percents for medullary tumors (n = 127) and invasive ductal tumors (n = 8096) of the full cohort were 76% and 64% [hazard ratio (HR) 0.52, P = 0.0005] and 66% and 57% (HR = 0.75, P = 0.03), respectively. For the restricted cohort, 14-year DRFI and OS percents for the medullary (n = 47) and invasive ductal tumors (n = 1407) were 89% and 63% (HR 0.24, P = 0.002) and 74% and 54% (HR = 0.55, P = 0.01), respectively. Competing risk analysis for DRFI favored medullary tumors (HR medullary/ductal = 0.32; 95% confidence interval = 0.13-0.78, P = 0.01). CONCLUSION: Medullary tumors have a favorable prognosis compared with invasive ductal tumors.


Assuntos
Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/mortalidade , Carcinoma Ductal de Mama/terapia , Carcinoma Medular/mortalidade , Carcinoma Medular/terapia , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Medular/patologia , Receptores ErbB/análise , Feminino , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Prognóstico , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Fatores de Risco , Taxa de Sobrevida , Resultado do Tratamento
3.
Breast Cancer Res Treat ; 131(3): 1061-6, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22080245

RESUMO

Prior studies have suggested a higher prevalence of high grade, ER-negative, HER2-positive, and basal-like carcinomas in young women with breast cancer. However, the precise distribution of poor prognostic features in this population remains unclear. We examined the pathologic features and distribution of molecular phenotype in relation to patient age in a large group of young women (≤40 years) with invasive breast cancer. Medical records were reviewed for clinical characteristics, tumor stage, and receptor status. Pathologic features, including those features associated with basal-like carcinomas, were examined by central review. Using tumor grade and biomarker expression, cancers were categorized as luminal A (ER+ and/or PR+ and HER2-, histologic grade 1 or 2); luminal B (ER+ and/or PR+ and HER2+, or ER and/or PR+, HER2- and grade 3); HER2 (ER and PR- and HER2+); and triple negative (ER-, PR-, and HER2-). Among 399 women of ≤40 years, 33% had luminal A tumors, 35% luminal B, 11% HER2 (ER-negative), and 21% triple negative. Compared to published results for all breast cancers, a greater proportion of young women had luminal B tumors, and a lesser proportion had luminal A. There were no significant differences in molecular phenotype, tumor stage or grade among the different age groups of young women. However, this population of young women presented with a different distribution of molecular phenotypes compared to the general population of women with breast cancer. These findings may have implications with regard to the etiology and prognosis of breast cancer in young women.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Adolescente , Adulto , Fatores Etários , Estudos de Coortes , Feminino , Humanos , Estadiamento de Neoplasias , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Adulto Jovem
5.
Tissue Antigens ; 77(3): 206-17, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21299525

RESUMO

The high degree of polymorphism at human leukocyte antigen (HLA) class I and class II loci makes high-resolution HLA typing challenging. Current typing methods, including Sanger sequencing, yield ambiguous typing results because of incomplete genomic coverage and inability to set phase for HLA allele determination. The 454 Life Sciences Genome Sequencer (GS FLX) next generation sequencing system coupled with conexio atf software can provide very high-resolution HLA genotyping. High-throughput genotyping can be achieved by use of primers with multiplex identifier (MID) tags to allow pooling of the amplicons generated from different individuals prior to sequencing. We have conducted a double-blind study in which eight laboratory sites performed amplicon sequencing using GS FLX standard chemistry and genotyped the same 20 samples for HLA-A, -B, -C, DPB1, DQA1, DQB1, DRB1, DRB3, DRB4, and DRB5 (DRB3/4/5) in a single sequencing run. The average sequence read length was 250 base pairs and the average number of sequence reads per amplicon was 672, providing confidence in the allele assignments. Of the 1280 genotypes considered, assignment was possible in 95% of the cases. Failure to assign genotypes was the result of researcher procedural error or the presence of a novel allele rather than a failure of sequencing technology. Concordance with known genotypes, in cases where assignment was possible, ranged from 95.3% to 99.4% for the eight sites, with overall concordance of 97.2%. We conclude that clonal pyrosequencing using the GS FLX platform and CONEXIO ATF software allows reliable identification of HLA genotypes at high resolution.


Assuntos
Antígenos HLA/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/tendências , Alelos , Sequência de Bases , Método Duplo-Cego , Características da Família , Genótipo , Antígenos HLA/análise , Humanos , Modelos Biológicos , Dados de Sequência Molecular , Estudos Multicêntricos como Assunto , Análise de Sequência de DNA/métodos , Software
6.
Ann Oncol ; 21(4): 741-747, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19713245

RESUMO

BACKGROUND: Young women with breast cancer have an increased risk for harboring a BRCA1 or BRCA2 mutation. Frequency of genetic testing and factors associated with testing have not been well described in this population. PATIENTS AND METHODS: We evaluated the rate of genetic testing among young breast cancer survivors identified through the Young Survival Coalition (YSC), an advocacy group for young women with breast cancer. Items regarding family history and genetic testing were included in a Web-based cross-sectional survey. RESULTS: A total of 701 women were eligible based on a history of breast cancer diagnosed < or =40 years. Mean age at diagnosis was 32.9 years and mean age at survey 35.7 years. About 41% reported a first- or second-degree relative with breast or ovarian cancer. About 24% had undergone genetic testing, and 26% of those tested reported that a mutation was found. By multivariate logistic regression, likelihood of having undergone testing was higher in women who were younger at diagnosis, were more educated, had a first- or second-degree relative with breast or ovarian cancer, had a mastectomy rather than breast conservation, and considered themselves at high risk for a cancer-predisposing mutation. CONCLUSION: Most women diagnosed with breast cancer < or =40 years do not undergo genetic testing.


Assuntos
Neoplasias da Mama/epidemiologia , Carcinoma/epidemiologia , Testes Genéticos/estatística & dados numéricos , Adulto , Fatores Etários , Idade de Início , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/etiologia , Neoplasias da Mama/genética , Carcinoma/diagnóstico , Carcinoma/etiologia , Carcinoma/genética , Coleta de Dados , Feminino , Genes BRCA1 , Genes BRCA2 , Aconselhamento Genético/estatística & dados numéricos , Predisposição Genética para Doença , Testes Genéticos/métodos , Humanos , Internet , Mutação/fisiologia , Fatores de Risco , Adulto Jovem
7.
Science ; 269(5231): 1692-6, 1995 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-7569895

RESUMO

The behavioral and cognitive effects of nicotine suggest that nicotinic acetylcholine receptors (nAChRs) participate in central nervous system (CNS) function. Although nAChR subunit messenger RNA (mRNA) and nicotine binding sites are common in the brain, there is little evidence for synapses mediated by nAChRs in the CNS. To test whether, CNS nAChRs might modify rather than mediate transmission, the regulation of excitatory synaptic transmission by these receptors was examined. Nanomolar concentrations of nicotine enhanced both glutamatergic and cholinergic synaptic transmission by activation of presynaptic nAChRs that increased presynaptic [Ca2]i. Pharmacological and subunit deletion experiments reveal that these presynaptic nAChRs include the alpha 7 subunit. These findings reveal that CNS nAChRs enhance fast excitatory transmission, providing a likely mechanism for the complex behavioral effects of nicotine.


Assuntos
Encéfalo/fisiologia , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Terminações Pré-Sinápticas/fisiologia , Receptores Nicotínicos/fisiologia , Transmissão Sináptica/efeitos dos fármacos , Animais , Sequência de Bases , Sítios de Ligação , Encéfalo/efeitos dos fármacos , Bungarotoxinas/metabolismo , Bungarotoxinas/farmacologia , Cálcio/fisiologia , Embrião de Galinha , Técnicas de Cultura , Gânglios Simpáticos/efeitos dos fármacos , Gânglios Simpáticos/fisiologia , Ácido Glutâmico/metabolismo , Dados de Sequência Molecular , Nicotina/metabolismo , Agonistas Nicotínicos/metabolismo , Terminações Pré-Sinápticas/química , Terminações Pré-Sinápticas/efeitos dos fármacos , Receptores Nicotínicos/análise , Sinapses/efeitos dos fármacos , Sinapses/fisiologia , Núcleos Talâmicos/efeitos dos fármacos , Núcleos Talâmicos/fisiologia
8.
Breast ; 47: 85-92, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31362134

RESUMO

OBJECTIVES: Most research addressing needs and concerns of young patients with breast cancer (≤40 years) is retrospective. The HOHO European protocol is a prospective multicenter cohort study of young women with newly diagnosed breast cancer, about fertility, psychosocial and quality of life concerns. Here we report the baseline data and focus on predictors of fertility concerns. MATERIALS AND METHODS: Patient surveys and medical record review were used. The baseline survey included sociodemographic, medical and treatment data as well as questions on fertility concerns and preservation strategies. Subscales from the CAncer Rehabilitation Evaluation System-Short Form (CARES-SF) were administered to measure specific quality of life aspects. Uni- and multivariable modeling were used to investigate predictors of greater fertility concern. RESULTS: Among 297 eligible respondents, 67% discussed fertility issues before starting therapy, 64% were concerned about becoming infertile after treatment, and 15% decided not to follow prescribed therapies. Fifty-four percent of women wished future children before diagnosis; of these, 71% still desired biologic children afterwards. In multivariable analysis, not having children was the only patient characteristic significantly associated with fertility concerns at diagnosis. Twenty-seven percent used fertility preservation strategies. Women who received chemotherapy reported greater physical (p = 0.021) and sexual difficulties (p = 0.039) than women who did not. Women who were married or had a partner reported less psychosocial problems than single women (p = 0.039). CONCLUSIONS: Young women with newly diagnosed breast cancer have several concerns, including, but not limited to, fertility. The HOHO European study provides valuable information to develop targeted interventions.


Assuntos
Neoplasias da Mama/diagnóstico , Tomada de Decisões , Preservação da Fertilidade/psicologia , Preservação da Fertilidade/estatística & dados numéricos , Qualidade de Vida , Adulto , Fatores Etários , Neoplasias da Mama/psicologia , Neoplasias da Mama/terapia , Estudos de Coortes , Europa (Continente) , Feminino , Humanos , Itália , Estudos Longitudinais , Estudos Prospectivos , Medição de Risco , Inquéritos e Questionários , Suíça , Estados Unidos
9.
J Neurosci ; 19(21): 9298-305, 1999 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-10531434

RESUMO

Transcripts for the beta2 and the beta4 nicotinic acetylcholine receptor (nAChR) subunits are found throughout the CNS and the peripheral nervous system. These two beta subunits can form heteromultimeric channels with any of the alpha2, alpha3, alpha4, or alpha5 subunits in heterologous expression systems. Nonetheless, the subunit composition of native nAChRs and the role of different nAChR subtypes in vivo remain unclear. We prepared null mutations for the beta2 and the beta4 genes and bred beta2-/-beta4-/- mice by mating mice of identical beta2-/-beta4+/- or beta2+/-beta4-/- genotype. The beta2-/- and the beta4-/- single-mutant mice grow to adulthood with no visible phenotypic abnormalities. The beta2-/-beta4-/- double mutants survive to birth but have impaired growth and increased perinatal mortality. They also present enlarged bladders with dribbling urination and develop urinary infection and bladder stones. The ocular pupils are widely dilated and do not constrict in response to light. Histological studies revealed no significant abnormalities of brain or peripheral tissues except for hyperplasia in the bladder mucosa of beta4-/- and beta2-/-beta4-/- mutants. Bladder strips from beta2-/-beta4-/- mice did not respond to nicotine but contracted when stimulated with a muscarinic agonist or electric field stimulation. Bladder strips from beta4 mutants did not respond to nicotine despite the absence of major bladder dysfunction in vivo. Acetylcholine-activated whole-cell currents were absent in superior cervical ganglion neurons from beta2-/-beta4-/- mice and reduced in neurons from beta4-/- mice. Although there is apparent redundancy and a superficially normal phenotype in beta2-/- and beta4-/- mice, physiological studies indicate major deficits in the beta4-/- mice. Our previous description of a similar phenotype in alpha3-/- mice and the current data suggest that the alpha3 and the beta4 subunits are major components in autonomic nAChRs. The phenotype of the beta2-/-beta4-/- and alpha3-/- mice resembles the autosomal recessive megacystis-microcolon-hypoperistalsis syndrome in humans.


Assuntos
Doenças do Sistema Nervoso Autônomo/genética , Neurônios/fisiologia , Receptores Nicotínicos/fisiologia , Gânglio Cervical Superior/fisiopatologia , Animais , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Células Cultivadas , Cruzamentos Genéticos , Éxons , Anormalidades do Olho/genética , Anormalidades do Olho/patologia , Feminino , Biblioteca Genômica , Íntrons , Substâncias Macromoleculares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Knockout , Mucosa/anormalidades , Mucosa/patologia , Neurônios/efeitos dos fármacos , Nicotina/farmacologia , Receptores Nicotínicos/deficiência , Receptores Nicotínicos/genética , Gânglio Cervical Superior/fisiologia , Bexiga Urinária/anormalidades , Bexiga Urinária/patologia
10.
J Clin Oncol ; 19(6): 1671-5, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11250996

RESUMO

PURPOSE: To evaluate the impact of subsequent pregnancy on the prognosis of patients with early breast cancer. PATIENTS AND METHODS: One hundred eight patients who became pregnant after diagnosis of early-stage breast cancer were identified in institutions participating in International Breast Cancer Study Group (IBCSG) studies. Fourteen had relapse of breast cancer before their first subsequent pregnancy. The remaining 94 patients (including eight who relapsed during pregnancy) formed the study group reported here. A comparison group of 188 was obtained by randomly selecting two patients, matched for nodal status, tumor size, age, and year of diagnosis from the IBCSG database, who were free of relapse for at least as long as the time between breast cancer diagnosis and completion of pregnancy for each pregnant patient. Survival comparison used Cox proportional hazards regression models. RESULTS: Overall 5- and 10-year survival percentages (+/- SE) measured from the diagnosis of early-stage breast cancer among the 94 study group patients were 92% +/- 3% and 86% +/- 4%, respectively. For the matched comparison group survival was 85% +/- 3% at 5 years and 74% +/- 4% at 10 years (risk ratio, 0.44; 95% confidence interval, 0.21 to 0.96; P =.04). CONCLUSION: Subsequent pregnancy does not adversely affect the prognosis of early-stage breast cancer. The superior survival seen in this and other controlled series may merely reflect a healthy patient selection bias, but is also consistent with an antitumor effect of the pregnancy.


Assuntos
Neoplasias da Mama/patologia , Recidiva Local de Neoplasia , Complicações Neoplásicas na Gravidez , Adolescente , Adulto , Intervalo Livre de Doença , Feminino , Humanos , Estadiamento de Neoplasias , Gravidez , Prognóstico , Estudos Retrospectivos
11.
J Clin Oncol ; 17(7): 2144-52, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10561270

RESUMO

PURPOSE: To describe quality-of-life considerations in post-remission therapies for children with acute myelogenous leukemia. PATIENTS AND METHODS: A quality-adjusted survival analysis, using the quality-adjusted time without symptoms or toxicity (Q-TWiST) method, was applied to Pediatric Oncology Group Trial 8821, which compared randomized assignment with intensive consolidation chemotherapy (CC) or autologous bone marrow transplantation (ABMT). Nonrandomized assignment to allogeneic bone marrow transplantation (allo BMT) on the basis of availability of a matched related donor was also evaluated. A 25-patient cohort provided data for modeling chronic graft-versus-host disease. The Q-TWiST analysis was performed based on the intent-to-treat principle. RESULTS: As previously reported, the 3-year event-free survival was not significantly different between the randomized arms (CC v ABMT). At a median follow-up of 5 years (of the censoring distribution), the CC group had less time in toxicity (TOX) and more time without symptoms or toxicity (TWiST), relapse-free time, and alive time than patients assigned to ABMT (none of these were statistically significant). Compared with the CC group, allo BMT patients spent more time in TOX (P <.001), more time in TWiST (P =.06), and had more relapse-free time (P =.03) and time alive (P =.07). Allo BMT was superior to ABMT with greater time in TWiST (P =.02), relapse-free time (P =.01), and time alive P =.002). CONCLUSION: The Q-TWiST analysis is a powerful decision aid in choosing among alternative therapies. Prospective information on patient preferences will facilitate future trials evaluating treatment outcomes. Refinements in the Q-TWiST method could be included to further enhance the power of this patient care decision-making tool.


Assuntos
Antineoplásicos/uso terapêutico , Transplante de Medula Óssea , Técnicas de Apoio para a Decisão , Leucemia Mieloide/terapia , Qualidade de Vida , Doença Aguda , Transplante de Medula Óssea/efeitos adversos , Criança , Ensaios Clínicos como Assunto/estatística & dados numéricos , Humanos , Leucemia Mieloide/mortalidade , Análise de Sobrevida , Estados Unidos/epidemiologia
12.
J Clin Oncol ; 19(21): 4141-9, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11689582

RESUMO

PURPOSE: We investigated tumor- and patient-related features that might influence the response to perioperative chemotherapy (PeCT) compared with no adjuvant therapy for patients with node-negative breast cancer. PATIENTS AND METHODS: A total of 1,275 patients were randomized to either no adjuvant treatment (427 patients) or PeCT (848 patients). The following variables thought to have prognostic significance were evaluated: grade, tumor size, estrogen (ER) and progesterone receptor (PgR) content (absent; low, 1 to 9 fmol/mg cytosol protein; or positive, > or = 10 fmol/mg cytosol protein), c-erbB-2 overexpression, menopausal status, and age. Cox proportional hazards regression models were used to assess the relative influence of these factors to predict the effect of PeCT on disease-free survival (DFS). Median follow-up was 13.5 years. RESULTS: The 10-year DFS percentage for 692 premenopausal patients did not significantly differ between the PeCT and no-adjuvant-treatment groups: 61% and 59%, respectively (relative risk [RR], 0.95; 95% confidence interval [CI], 0.75 to 1.20; P = .70). No predictive factors were identified. For 583 postmenopausal patients, 10-year DFS percentages for the groups were 63% and 58%, respectively (RR, 0.75; 95% CI, 0.58 to 0.93; P = .03). The absence of expression of ER, PgR, or both ER and PgR was the most important factor predicting improved outcome with PeCT among postmenopausal patients. The 10-year DFS percentages were 85% and 53% for the steroid hormone receptor-absent cohort of treated and untreated patients, respectively (RR, 0.18; 95% CI, 0.06 to 0.49; P = .0009). CONCLUSION: The role of PeCT should be explored for patients whose primary tumors do not express steroid hormone receptors, because it is likely that early initiation of treatment is exclusively relevant for such patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Mastectomia , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Pós-Menopausa , Modelos de Riscos Proporcionais , Receptor ErbB-2/metabolismo , Análise de Sobrevida
13.
Endocrinology ; 131(6): 2839-45, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1446622

RESUMO

We investigated the effects of 8 days of LH withdrawal on rat Leydig cell peroxisomal volume, total and intraperoxisomal catalase and sterol carrier protein-2 (SCP2) contents, and LH-stimulated testosterone secretion in vitro. Three groups of adult male Sprague-Dawley rats, i.e. control, TE-implanted (testosterone-17 beta-estradiol-filled Silastic implants to suppress LH), and TELH-implanted (TE-implanted and LH replacement via Alzet mini osmotic pumps), were used. After 8 days, Leydig cell organelle volumes (stereology), intraperoxisomal catalase and SCP2 contents (immunocytochemistry), LH-stimulated testosterone secretion by isolated Leydig cells in vitro (determined by RIA), and total catalase and SCP2 contents in equal numbers of Leydig cells (immunoblot analyses) were determined. Results showed that the TELH-implanted rats were identical to controls in every parameter tested. Testis volume and Leydig cell number per testis in control and TE-implanted rats were not significantly different; however, reductions (P < 0.05) were observed in the average volume of a Leydig cell (one third of controls) and the volume of Leydig cells per testis. All Leydig cell organelle volumes tested were significantly lower in TE-implanted rats than in the controls; however, the volumes of smooth endoplasmic reticulum (SER) and peroxisomes were the most reduced (lowered to one sixth of control values). LH-stimulated testosterone secretion per Leydig cell in vitro correlated well with these changes in the volumes of Leydig cell SER and peroxisomes. Intraperoxisomal catalase in Leydig cells was unchanged in TE-implanted rats, although immunoblotting demonstrated a loss of total catalase content (which reflected the reduction in the volume of peroxisomes). SCP2 in Leydig cells of TE-implanted rats was undetectable with immunoblot analysis (explained by the reductions in Leydig cell peroxisome volume and intraperoxisomal SCP2). These results demonstrate that the organelles SER and peroxisomes and the protein SCP2 in Leydig cells are more LH dependent than the other organelles (e.g. mitochondria, lysosomes) and protein catalase, respectively. Moreover, the findings of this study are consistent with the hypothesis that Leydig cell peroxisomes play a significant role in testosterone production.


Assuntos
Proteínas de Transporte/metabolismo , Células Intersticiais do Testículo/metabolismo , Células Intersticiais do Testículo/ultraestrutura , Hormônio Luteinizante/administração & dosagem , Microcorpos/ultraestrutura , Proteínas de Plantas , Esteróis/metabolismo , Animais , Catalase/metabolismo , Estradiol/farmacologia , Immunoblotting , Células Intersticiais do Testículo/efeitos dos fármacos , Hormônio Luteinizante/farmacologia , Masculino , Microcorpos/enzimologia , Organelas/efeitos dos fármacos , Organelas/ultraestrutura , Ratos , Ratos Sprague-Dawley , Testículo/anatomia & histologia , Testículo/efeitos dos fármacos , Testosterona/metabolismo , Testosterona/farmacologia
14.
Endocrinology ; 127(4): 1792-803, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1698146

RESUMO

The neonatal period is a time of transition between pituitary-independent fetal growth and the pituitary-dependent growth seen in older mammals. To evaluate pituitary-dependent neonatal growth, Wistar rats were hypophysectomized (Hx) on postnatal day 6. Nineteen days post-Hx, body weight and tail length were inhibited 48% and 34%, respectively, compared with sham-Hx controls. Organ weights determined on days 10, 15, 20, 25, and 30 revealed three patterns of pituitary-dependence: 1) pituitary-independent growth in the brain and lung; 2) moderate pituitary-dependent growth in the heart, liver, kidney, and intestine; and 3) marked pituitary-dependent growth in the adrenals, spleen, and testes. Both serum insulin-like growth factor (IGF)-I and -II levels fell significantly in Hx pups by 54 h after Hx (P = 0.0005), and Northern analysis on day 15 showed a significant decrease in liver messenger RNA (mRNA) for IGF-II. Analysis of the major IGF binding proteins (BPs) was performed by Western ligand blots. Hx performed on day 6 resulted in a linear decrease in the amount of the 22k BP from day 10 to day 30. In contrast, the major neonatal BP (IGFBP-2, a 29.5k molecule) showed a biphasic response to neonatal Hx. On postnatal day 10, 4 days after Hx, a significant decrease in IGFBP-2 occurred, which persisted through day 15; by postnatal day 20 and continuing through postnatal day 30, the amount of IGFBP-2 in the serum dramatically increased. The 40 to 50k fraction of IGFBP-3 first appeared in significant quantities by postnatal day 20, and after Hx dropped to 10% of sham-control values. Similarly, Northern analysis on day 15 demonstrated a significant decrease in liver, but not brain, mRNA for IGFBP-2 after Hx, whereas on postnatal day 25, liver mRNA for IGFBP-2 was increased in Hx pups compared with sham controls. We conclude that the pituitary gland exerts significant but selective effects on neonatal growth, with the notable exception of brain growth. Serum levels of both IGF-I and IGF-II, as well as their BPs, are pituitary dependent in the neonatal period. Pituitary-dependent neonatal growth thus appears to be mediated by IGF and modulated by IGF-binding proteins. On the other hand, that portion of the persistent growth in the neonatal Hx rat that is independent of the pituitary-IGF axis may be a good model for investigation of fetal growth.


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Proteínas de Transporte/metabolismo , Hipofisectomia , Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Hipófise/fisiologia , Somatomedinas/metabolismo , Glândulas Suprarrenais/crescimento & desenvolvimento , Envelhecimento/fisiologia , Animais , Química Encefálica , Proteínas de Transporte/genética , Glicosilação , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina , Fator de Crescimento Insulin-Like II/genética , Fígado/análise , Masculino , Hibridização de Ácido Nucleico , Tamanho do Órgão , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos , Baço/crescimento & desenvolvimento , Cauda/crescimento & desenvolvimento , Testículo/crescimento & desenvolvimento , Aumento de Peso
15.
Endocrinology ; 127(6): 2947-54, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2249635

RESUMO

The aim of the present study was to investigate the effects of a single injection of LH on rat Leydig cell peroxisome volume and peroxisomal sterol carrier protein-2 (SCP2) content. Sexually mature Sprague-Dawley rats (n = 5) were injected sc with 500 micrograms LH and euthanized, and trunk blood was collected at 0, 0.5, 1, 2, and 3 h. Additionally, LH-treated rats were whole body perfused-fixed, and their testes were processed for qualitative and quantitative histochemical and immunocytochemical studies at 0, 0.5, 1, and 2 h. Peroxisomes were identified by cytochemical staining for catalase activity with the alkaline 3,3'-diaminobenzidine tetrahydrochloride method. Catalase and SCP2 were immunolocalized in Leydig cell organelles via 10-nm AuroProbe EM protein-A gold particles. Peak plasma testosterone concentrations were observed 1 and 2 h after the single sc LH injection. The average volume of a Leydig cell was unchanged by the LH treatment at all time points tested. Similarly, the absolute volumes of smooth endoplasmic reticulum and mitochondria per Leydig cell were unchanged at all time points tested. By contrast, the absolute volume of peroxisomes per Leydig cell increased 3-fold 0.5 h after LH injection (P less than 0.01) and then returned to control values by 2 h. The absolute volume of negative bodies (single membrane-bound cytoplasmic organelles lacking catalase) per Leydig cell was elevated above the control value 0.5 and 1 h after LH injection. Western blot analysis demonstrated a single protein at 14 and 60 kDa with anti-SCP2 and anticatalase, respectively, for both homogenates obtained from liver and purified Leydig cells. Quantitative immunocytochemical studies demonstrated that the gold particle density representing SCP2 over peroxisomes increased 5-fold 0.5 h after the LH injection (P less than 0.01) and then returned to control values by 2 h. In contrast, the gold particle density representing catalase over peroxisomes was not different in control and LH-injected groups. We conclude that a single sc injection of LH causes a rapid, specific, and transient increase in both the volume of peroxisomes and the peroxisomal content of SCP2 in Leydig cells.


Assuntos
Proteínas de Transporte/metabolismo , Células Intersticiais do Testículo/ultraestrutura , Hormônio Luteinizante/farmacologia , Microcorpos/ultraestrutura , Proteínas de Plantas , Esteróis/metabolismo , Animais , Anticorpos , Proteínas de Transporte/isolamento & purificação , Immunoblotting , Cinética , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Masculino , Microcorpos/efeitos dos fármacos , Microcorpos/metabolismo , Microscopia Eletrônica , Peso Molecular , Ratos , Ratos Endogâmicos , Valores de Referência , Testosterona/sangue , Testosterona/metabolismo
16.
J Natl Cancer Inst Monogr ; (30): 44-51, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11773291

RESUMO

Breast cancer rarely occurs in women below the age of 35 years. Data from various sources indicate that diagnosis at such an age is associated with a dire prognosis mainly because of a more aggressive presentation. Although the effect of chemotherapy for premenopausal patients is substantial, recent evidence on 2233 patients suggested that very young women with endocrine-responsive tumors had a statistically significantly higher risk of relapse than older premenopausal patients with such tumors. In contrast, results for younger and older premenopausal patients were similar if their tumors were classified as endocrine nonresponsive. Information from studies on 7631 patients who were treated with chemotherapy alone in trials of three major U.S. cooperative groups showed a similar interaction between the effect of age and steroid hormone receptor status of the primary tumor. Better treatments for very young patients are required and may involve ovarian function suppression in addition to other endocrine agents in patients with endocrine responsive tumors and a more precise investigation of chemotherapy and its timing, duration, and intensity in those with endocrine nonresponsive tumors. Very young women with this disease are faced with personal, family, professional, and quality-of-life issues, which further complicate the phase of treatment decision making. The development of more effective therapies for younger patients requires tailored treatment investigations and cannot rely on information predominantly contributed from older premenopausal women.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante/métodos , Pré-Menopausa/fisiologia , Adulto , Idade de Início , Envelhecimento/fisiologia , Amenorreia/induzido quimicamente , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Quimioterapia Adjuvante/estatística & dados numéricos , Intervalo Livre de Doença , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Neoplasias Hormônio-Dependentes/diagnóstico , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias Hormônio-Dependentes/epidemiologia , Neoplasias Hormônio-Dependentes/patologia , Avaliação de Resultados em Cuidados de Saúde , Pós-Menopausa/fisiologia , Prognóstico , Receptores de Estrogênio/metabolismo , Tamoxifeno/uso terapêutico
17.
Ann N Y Acad Sci ; 637: 152-63, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1785769

RESUMO

Leydig cell progenitors contain significant concentrations of androgen receptors. When the metabolism of DHT to 3 alpha-DIOL is blocked, DHT stimulates testosterone production by Leydig cell progenitors, most probably via an androgen receptor dependent mechanism. Rapid metabolism by 3 alpha-HSD may limit the potency of exogenous DHT to stimulate differentiation of Leydig cell progenitors in vitro. Insulin-like growth factor-I enhances androgen production by purified immature Leydig cells. The elevated sensitivity of immature Leydig cells versus adult Leydig cells to IGF-I stimulation indicates that this peptide hormone has a role in their differentiation during puberty.


Assuntos
Androgênios/fisiologia , Células Intersticiais do Testículo/citologia , Androgênios/metabolismo , Animais , Diferenciação Celular , Di-Hidrotestosterona/metabolismo , Fator de Crescimento Insulin-Like I/fisiologia , Masculino , Ratos , Receptores Androgênicos/metabolismo , Testosterona/metabolismo , Testosterona/fisiologia
18.
Recent Results Cancer Res ; 152: 373-89, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9928573

RESUMO

In the breast cancer adjuvant therapy setting, the critical issue to consider in treatment decision-making is the tradeoff between quality and quantity of life. The toxicities of adjuvant therapies, both acute and late, must be balanced against the potential benefits of delayed recurrence and improved survival. The question should be addressed concerning when quality-of-life assessment is relevant in the adjuvant setting. Such assessments can inform patients about what to expect from their treatment, describe quality-of-life differences between treatments, provide an additional baseline measure with potential prognostic significance, inform clinicians about their patients' experiences with toxicities, indicate situations in which psychosocial interventions might be useful, and document patient adaptation to diagnosis and treatment. The relevance of quality-of-life assessment in the adjuvant setting can be illustrated by investigating one of the most controversial questions of today: When should chemotherapy be added to tamoxifen for postmenopausal patients? Data from the International Breast Cancer Study Group (IBCSG) Trial VII showed that adding 3 months of CMF (cyclophosphamide 100 mg/m2 orally days 1-14; methotrexate 40 mg/m2 i.v. days 1, 8; fluorouracil 600 mg/m2 i.v. days 1, 8; repeated every 28 days) to tamoxifen significantly improved disease-free survival compared with tamoxifen alone. The Quality-adjusted Time Without Symptoms of disease or Toxicity of treatment (QTWiST) method was used to compare the adjuvant therapies with respect to quality-adjusted survival. The analysis indicated that the decision to use adjuvant chemotherapy in this setting should be based on patient preferences concerning the relative importance of treatment toxicity versus disease recurrence.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Qualidade de Vida , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/mortalidade , Quimioterapia Adjuvante , Ensaios Clínicos como Assunto , Estudos de Avaliação como Assunto , Feminino , Humanos , Taxa de Sobrevida , Tamoxifeno/uso terapêutico
19.
J Androl ; 13(2): 125-30, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1597396

RESUMO

Leydig cells were isolated and purified from adult and midpubertal rats to study the effects of insulin-like growth factor-I (IGF-I) on steroidogenesis. Androgen production, as measured in Leydig cell conditioned culture media, from four different treatment groups (1 = no hormone; 2 = 70 ng/ml IGF-I; 3 = 0.1 ng/ml LH; 4 = 70 ng/ml IGF-I + 0.1 ng/ml LH) were compared daily. After 3 days in culture, the cells were treated with a maximally stimulating dose of luteinizing hormone (LH) (100 ng/ml) for 3 hours. Androgen production was highest in the cells treated with both IGF-I and low concentrations of LH. In the presence of IGF-I, regardless of LH, cells derived from pubertal animals had a greater increase in steroidogenesis during the culture period than did cells from adult animals. Pretreatment with IGF-I prior to maximal LH stimulation induced a greater increase in androgen production in cells from pubertal rats than in cells from adult animals. It is concluded that IGF-I has a direct effect on Leydig cells and may act synergistically with LH to promote androgen synthesis. The greater response in pubertal cells raises the possibility that IGF-I is important in the maturing process of the testis.


Assuntos
Envelhecimento/metabolismo , Androgênios/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/metabolismo , Animais , Separação Celular , Células Cultivadas , Relação Dose-Resposta a Droga , Células Intersticiais do Testículo/efeitos dos fármacos , Hormônio Luteinizante/farmacologia , Masculino , Ratos , Ratos Endogâmicos , Fatores de Tempo
20.
Tissue Cell ; 27(6): 689-99, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8578559

RESUMO

The present study investigated the effects of aging in the testis interstitium in Sprague Dawley rats. Rats of 3, 6 and 24 months of age were used. Testes of rats (n = 5) were fixed by whole body perfusion using a fixative containing 2.5% glutaraldehyde in cacodylate buffer, processed and embedded in eponaraldite. Using 1 microns sections stained with methylene blue, qualitative and quantitative morphological studies were performed. Purified Leydig cell preparations, obtained by collagenase digestion followed by elutriation and density gradient centrifugation, were used to determine luteinizing hormone (LH; 100 ng/ml) stimulated testosterone secretory capacity per Leydig cell in vitro. Testosterone levels in the incubation medium, and testosterone and luteinizing hormone levels in serum of these three groups of rats were determined via radioimmunoassay. Morphological studies revealed that Leydig cells were more abundant in the testis interstitium at 6 and 24 months when compared to 3 months. Moreover, collagen fiber bundles were more frequently observed in the testis interstitium at older ages. Blood vessels of the testis interstitium in 24-month-old rats frequently showed partial and complete occlusion of their lumen and thickening of vessel walls. This feature was also present at 6 months, but less frequently. The results of the stereological studies revealed that the volumes of seminiferous tubules, interstitium and Leydig cells per testis was significantly higher (P < 0.05), at 6 and 24 months of age than those at 3 months. Moreover, volume of macrophages per testis was observed to be significantly higher (P < 0.05) at 6 months when compared to 3 and 24 months, and volume of connective tissue cells per testis was observed to be significantly lower (P < 0.05) at 6 and 24 months when compared to 3 months of age. No significant difference (P > 0.05) was observed for the volume of lymphatic space per testis in the three age groups studied. Volume of interstitial blood vessels per testis was not significantly different at 3 and 6 months of age, but a significantly greater (P < 0.05) volume was observed at 24 months. However, at 6 and 24 months, only 71% and 31% of the total blood vessel volumes respectively had completely open lumen in them; the rest of the blood vessels were either partially (12.5% at 6 months and 17% at 24 months) or completely (16.5% at 6 months and 52% at 24 months) occluded. The number of Leydig cells per testis was doubled at 6 and 24 months of age compared to 3 months. The average volume of a Leydig cell was not significantly different between 3 and 6 months of age, however, at 24 months a significantly lower (P < 0.05) value was observed. LH stimulated testosterone secretory capacity per Leydig cell in vitro was reduced by 50% at 6 months of age compared to 3 months; a further significant (P < 0.05) reduction was observed at 24 months. Serum testosterone and LH levels were not significantly different between 3 and 6 months of age but at 24 months a significantly lower (P < 0.05) value was observed for both of these hormones. In summary, the present study demonstrated many changes in the components of the testis interstitium in the aged Sprague Dawley rat. Modifications in the blood vessels and the occurrence of abundant collagen fibers in the interstitial space could possibly contribute to the reduced testosterone secretory capacity per Leydig cell with advancing in age. The observed Leydig cell hyperplasia could be suggested as a compensatory effort to maintain the normal androgen status of the aged rat, which is rather successful at 6 months but unsuccessful at 24 months. This investigation further revealed that these characteristic changes in the aged testis interstitium at 24 months are also present to some extent at 6 months of age in Sprague Dawley rats, suggesting that aging of the testis in this strain of rats commences early in life.


Assuntos
Envelhecimento/patologia , Células Intersticiais do Testículo/patologia , Envelhecimento/sangue , Animais , Peso Corporal/fisiologia , Hormônio Luteinizante/sangue , Masculino , Radioimunoensaio , Ratos , Ratos Sprague-Dawley , Testosterona/sangue
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