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1.
Exp Neurol ; 241: 95-104, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23195594

RESUMO

The aim of this study was to search for neuropathological changes in postmortem brain tissue of individuals with cervical dystonia (CD). Multiple regions of formalin-preserved brains were collected from patients with CD and controls and examined with an extensive battery of histopathological stains in a two-stage study design. In stage one, 4 CD brains underwent a broad screening neuropathological examination. In stage two, these 4 CD brains were combined with 2 additional CD brains, and the subjective findings were quantified and compared to 16 age-matched controls. The initial subjective neuropathological assessment revealed only two regions with relatively consistent changes. The substantia nigra had frequent ubiquitin-positive intranuclear inclusions known as Marinesco bodies. Additionally, the cerebellum showed patchy loss of Purkinje cells, areas of focal gliosis and torpedo bodies. Other brain regions showed minor or inconsistent changes. In the second stage of the analysis, quantitative studies failed to reveal significant differences in the numbers of Marinesco bodies in CD versus controls, but confirmed a significantly lower Purkinje cell density in CD. Molecular investigations revealed 4 of the CD cases and 2 controls to harbor sequence variants in non-coding regions of THAP1, and these cases had lower Purkinje cell densities regardless of whether they had CD. The findings suggest that subtle neuropathological changes such as lower Purkinje cell density may be found in primary CD when relevant brain regions are investigated with appropriate methods.


Assuntos
Encéfalo/patologia , Torcicolo/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas Reguladoras de Apoptose/genética , Encéfalo/metabolismo , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Corpos de Inclusão Intranuclear/metabolismo , Corpos de Inclusão Intranuclear/patologia , Corpos de Lewy/patologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/genética , Células de Purkinje/metabolismo , Células de Purkinje/patologia , Torcicolo/genética , Ubiquitina/metabolismo , Adulto Jovem
2.
Stat Med ; 27(21): 4175-89, 2008 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-18613222

RESUMO

Longitudinal studies tracking the rate of change are subject to patient dropout. This dropout process might not only be informative but also heterogeneous in the sense that different causes might contribute to multiple patterns of informative dropout. We propose a random-effects approach to test for homogeneity of informative dropout that accommodates the realistic situation where reasons for dropout are not fully understood, or perhaps are even entirely unknown. The proposed score test is robust in that it does not depend on the underlying distribution of the informative dropout random effects. The test allows for an additional level of clustering among participating subjects, as might be found in a family study, provided the informative dropout random effects have a known correlation structure.


Assuntos
Interpretação Estatística de Dados , Estudos Longitudinais , Pacientes Desistentes do Tratamento , Doença de Alzheimer/patologia , Animais , Neoplasias da Mama/metabolismo , Cognição/fisiologia , Simulação por Computador , Fator 2 de Crescimento de Fibroblastos/farmacologia , Humanos , Camundongos , Neovascularização Patológica/tratamento farmacológico
3.
Neurology ; 64(5): 899-901, 2005 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-15753433

RESUMO

The authors examined the relationship between hypertension and cognitive performance in 34 African-American patients with probable Alzheimer disease. Multiple regression analyses indicated that hypertension was associated with poorer overall performance on the Mattis Dementia Rating Scale, particularly the Initiation/Perseveration and Conceptualization subscales, after controlling for gender, age, and education. The findings suggest that African-American patients with hypertension exhibit greater cognitive impairment, possibly reflecting executive dysfunction.


Assuntos
Doença de Alzheimer/complicações , Negro ou Afro-Americano/etnologia , Transtornos Cognitivos/complicações , Predisposição Genética para Doença/etnologia , Hipertensão/complicações , Negro ou Afro-Americano/genética , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/etnologia , Doença de Alzheimer/psicologia , Causalidade , Inibidores da Colinesterase/uso terapêutico , Transtornos Cognitivos/etnologia , Transtornos Cognitivos/psicologia , Depressão/complicações , Escolaridade , Feminino , Humanos , Hipertensão/etnologia , Hipertensão/psicologia , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Análise de Regressão , Fatores Sexuais
4.
Neurology ; 62(3): 411-3, 2004 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-14872022

RESUMO

BACKGROUND: Testosterone deficiency, a treatable condition commonly seen in aging men, has been linked to Parkinson disease (PD) and Alzheimer disease (AD). In normal subjects, low testosterone levels are associated with cognitive and neuropsychiatric symptoms, yet the relationship between testosterone levels and cognitive function in PD and AD remains unclear. OBJECTIVE: To examine the relationship of testosterone levels to age and cognitive function in PD and AD. METHODS: Plasma testosterone levels were determined in men enrolled in a clinical registry of subjects with PD and AD, and neuropsychological testing was performed on subjects who consented. Testosterone levels in men with PD were compared with those in men with AD. In both groups, the relationship between testosterone levels and neuropsychological test scores was analyzed, adjusting for age and education. RESULTS: Linear regression analysis revealed that testosterone levels decreased with age in male PD patients (p < 0.03) and male AD patients (p < 0.07). The rate of decline was similar for the two groups. In PD patients, lower testosterone levels were associated with poorer performance on Trails B Seconds (p < 0.02). CONCLUSIONS: There is a similar age-related decline in plasma testosterone levels in men with either PD or AD. Previously described associations between low testosterone levels and frontal lobe dysfunction in normal aged men, together with these results, suggest that the hormonal deficiency may act as a "second hit" to impair cognitive function in neurodegenerative disease.


Assuntos
Doença de Alzheimer/sangue , Doença de Parkinson/sangue , Testosterona/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/sangue , Doença de Alzheimer/psicologia , Transtornos Cognitivos/sangue , Transtornos Cognitivos/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Doença de Parkinson/psicologia , Testosterona/deficiência
6.
Neurology ; 57(10): 1923-5, 2001 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-11723294

RESUMO

The authors examined whether the APOE-epsilon4 allele is associated with an earlier age at onset of AD in 71 African American patients with probable AD. The authors found a linear dose effect in which each copy of the epsilon4 allele was associated with a 3.6-year earlier onset of AD, indicating a dose-dependent relationship between APOE-epsilon4 and age at onset of AD in African Americans.


Assuntos
Doença de Alzheimer/genética , Apolipoproteínas E/genética , População Negra/genética , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Alelos , Apolipoproteína E4 , Feminino , Dosagem de Genes , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
7.
Cancer Chemother Pharmacol ; 48(2): 95-103, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11561784

RESUMO

PURPOSE: To determine the maximum tolerated dose (MTD), dose-limiting toxicity (DLT), and effect of drug sequence on toxicities and pharmacokinetics of the combination of gemcitabine and docetaxel. METHODS: A total of 34 patients with advanced cancers were treated with gemcitabine and docetaxel on days 1 and 8 of each 21-day cycle according to the following dose escalation schedule: level 1, 800 and 30 mg/m2, respectively; level 2, 800 and 40 mg/m2; level 3, 1,000 and 40 mg/m2; and level 4, 1,250 and 40 mg/m2. At each dose level, at least three patients were assigned to one of the two sequences of drug administration: gemcitabine-->docetaxel or docetaxel-->gemcitabine. Once the MTD had been reached, six additional patients, who had received no more than one chemotherapy regimen, were enrolled to dose levels 3 and 4 (gemcitabine-->docetaxel) to determine the MTD in minimally pretreated patients. RESULTS: Neutropenia was the most frequent DLT with an overall incidence of 23.5%. Grade 3/4 neutropenia occurred in 62% of patients (8/13) who had received two or more prior chemotherapy regimens, but not at all (0/15) in patients who had received no more than one prior chemotherapy regimens (P< 0.001). Additional DLTs included grade 4 diarrhea and grade 4 stomatitis in one patient each. The MTD was determined to be gemcitabine 800 mg/m2 and docetaxel 40 mg/m2 in patients who had received two or more prior chemotherapy regimens. However, minimally pretreated patients (no more than one prior chemotherapy regimen) were able to tolerate higher doses with an MTD of gemcitabine 1,250 mg/m2 and docetaxel 40 mg/m2. There were no significant differences in toxicities or pharmacokinetics between the two sequences of administration. Partial and minor responses were observed in 23.5% of patients: non-small-cell lung (two of eight), gastric (two of three), head and neck (one of two), bladder (two of four) and hepatocellular cancer (one of one). CONCLUSIONS: The combination of gemcitabine and docetaxel administered on days 1 and 8 every 21 days was feasible and well tolerated in patients with advanced malignancies. The sequence of administration had no significant effect on the toxicity or pharmacokinetics of either drug. Minimally pretreated patients tolerated higher doses of this combination without significant toxicities. This schedule and combination demonstrated activity in a variety of solid tumors, and merits further evaluation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Neoplasias/metabolismo , Taxoides , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacocinética , Docetaxel , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Paclitaxel/administração & dosagem , Paclitaxel/análogos & derivados , Paclitaxel/farmacocinética , Gencitabina
8.
Am J Clin Pathol ; 114(4): 552-63, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11026101

RESUMO

Surveillance methods in Barrett esophagus (BE) using light microscopic examination of random biopsy specimens may miss focal dysplasia. In addition, dysplastic foci identified initially may not be relocated subsequently, making chemoprevention studies difficult. By using a special gastroscope, systematic mapping (4-quadrant biopsy specimens at 1-cm intervals) was performed in 22 patients (33 total mappings yielding 700 biopsy specimens). H&E, immunohistochemistry, and DNA ploidy analysis were performed. c-erbB-2 and positive Ki-67 were detected only in dysplastic sites; thus, their detection did not precede morphologically identifiable dysplasia. On the other hand, aneuploidy and p53 were detected in dysplastic and nondysplastic areas. p53 was correlated with dysplasia, and S-phase narrowly missed correlation, while aneuploidy was not correlated. PCNA and bcl-2 were ubiquitous, limiting their usefulness. On second maps, epithelial type was reidentified with 81% accuracy. A significant correlation was found between p53 and dysplasia. Sites of dysplasia and abnormal biomarkers could be relocated accurately by using endoscopic mapping. Therefore, mapping combined with biomarker studies may provide better surveillance and serve as a useful technique in chemoprevention studies.


Assuntos
Esôfago de Barrett/diagnóstico , Biomarcadores Tumorais , Endoscopia Gastrointestinal , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneuploidia , Esôfago de Barrett/genética , Esôfago de Barrett/metabolismo , Biomarcadores Tumorais/metabolismo , Biópsia , DNA/análise , Endoscopia Gastrointestinal/métodos , Feminino , Citometria de Fluxo , Seguimentos , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Técnicas Imunoenzimáticas , Masculino , Metaplasia/patologia , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
9.
J Clin Oncol ; 18(14): 2710-7, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10894870

RESUMO

PURPOSE: To determine the efficacy, safety, pharmacokinetics, and effect on serum angiogenic growth factors of two dose levels of thalidomide in patients with metastatic breast cancer. PATIENTS AND METHODS: Twenty-eight patients with progressive metastatic breast cancer were randomized to receive either daily 200 mg of thalidomide or 800 mg to be escalated to 1,200 mg. Fourteen heavily pretreated patients were assigned to each dose level. Each cycle consisted of 8 weeks of treatment. Pharmacokinetics and growth factor serum levels were evaluated. RESULTS: No patient had a true partial or complete response. On the 800-mg arm, 13 patients had progressive disease at or before 8 weeks of treatment and one refused to continue treatment. The dose was reduced because of somnolence to 600 mg for five patients and to 400 mg for two and was increased for one to 1,000 mg and for four to 1,200 mg. On the 200-mg arm, 12 patients had progressive disease at or before 8 weeks and two had stable disease at 8 weeks, of whom one was removed from study at week 11 because of grade 3 neuropathy and the other had progressive disease at week 16. Dose-limiting toxicities included somnolence and neuropathy. Adverse events that did not require dose or schedule modifications included constipation, fatigue, dry mouth, dizziness, nausea, anorexia, arrhythmia, headaches, skin rash, hypotension, and neutropenia. Evaluation of circulating angiogenic factors and pharmacokinetic studies failed to provide insight into the reason for the lack of efficacy. CONCLUSION: Single-agent thalidomide has little or no activity in patients with heavily pretreated breast cancer. Further studies that include different patient populations and/or combinations with other agents might be performed at the lower dose levels.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Talidomida/uso terapêutico , Adulto , Idoso , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/farmacocinética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Esquema de Medicação , Fatores de Crescimento Endotelial/metabolismo , Feminino , Fator 2 de Crescimento de Fibroblastos/metabolismo , Substâncias de Crescimento/metabolismo , Humanos , Linfocinas/metabolismo , Metaloproteinases da Matriz/metabolismo , Pessoa de Meia-Idade , Metástase Neoplásica , Estudos Prospectivos , Talidomida/administração & dosagem , Talidomida/farmacocinética , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
10.
Ann Oncol ; 11(1): 17-22, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10690382

RESUMO

BACKGROUND: Many breast cancer survivors suffer debilitating hot flashes. Estrogen, the drug of choice in perimenopausal women, is generally not recommenced to breast cancer survivors. Nonhormonal treatments are mostly disappointing. Anecdotal reports in our institution suggested that the selective serotonin-reuptake inhibitor, paroxetine hydrochloride, might be efficacious in alleviating hot flashes. PATIENTS AND METHODS: Thirty women with prior breast cancer who were suffering at least two hot flashes a day entered a single institution pilot trial to evaluate paroxetine's efficacy in reducing the frequency and severity of hot flashes. After completing daily diaries for one week on no therapy, the women received open-label paroxetine, 10 mg daily for one week, followed by four weeks of paroxetine, 20 mg daily. The women completed hot-flash daily diaries throughout the study period, and a health-related symptom-assessment questionnaire and a quality-of-life rating scale in the first and sixth week of the study. RESULTS: Twenty-seven women completed the six-week study period. The mean reduction of hot flash frequency was 67% (95% confidence interval (95% CI): 56%-79%). The mean reduction in hot flash severity score was 75% (95% CI: 66%-85%). There was a statistically significant improvement in depression, sleep, anxiety, and quality of life scores. Furthermore, 25 (83%) of the study participants chose to continue paroxetine therapy at the end of study. The most common adverse effect was somnolence, resulting in drug discontinuation in two women, and dose reduction in two women. One woman discontinued drug due to anxiety. CONCLUSIONS: Paroxetine hydrochloride is a promising new treatment for hot flashes in breast cancer survivors, and warrants further evaluation in a double-blind randomized placebo-controlled trial.


Assuntos
Neoplasias da Mama/fisiopatologia , Fogachos/prevenção & controle , Paroxetina/uso terapêutico , Qualidade de Vida , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Adulto , Idoso , Ansiedade , Neoplasias da Mama/psicologia , Neoplasias da Mama/reabilitação , Intervalos de Confiança , Depressão/prevenção & controle , Feminino , Humanos , Menopausa , Pessoa de Meia-Idade , Paroxetina/efeitos adversos , Projetos Piloto , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Comportamento Sexual , Inquéritos e Questionários , Sobreviventes
11.
Control Clin Trials ; 20(6): 555-66, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10588296

RESUMO

We present a modification to Simon's optimal design for phase II trials in which the objective is to minimize the median sample size rather than the expected sample size when the true response rate is poor (p = p0). We argue that the modified design may be preferred in smaller institutions when the focus is on a single or small number of phase II trials rather than a large program of phase II trials.


Assuntos
Ensaios Clínicos Fase II como Assunto/estatística & dados numéricos , Projetos de Pesquisa/estatística & dados numéricos , Tamanho da Amostra , Algoritmos , Estudos de Coortes , Simulação por Computador , Avaliação de Medicamentos , Humanos , Modelos Estatísticos , Seleção de Pacientes , Probabilidade , Indução de Remissão , Resultado do Tratamento
12.
J Gastrointest Surg ; 3(4): 426-31, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10482696

RESUMO

From November 1988 to May 1996, a prospective randomized study was undertaken to assess the efficacy of superselective intra-arterial chemotherapy for surgically proved unresectable gastric carcinoma. Each patient had undergone endoscopy as well as abdominal and pelvic CT scanning for staging. Patients with evidence of liver metastasis, peritoneal carcinomatosis, enlarged retroperitoneal lymph nodes, or locally advanced disease beyond curative resection were excluded from the study. A total of 386 patients with potentially curable disease were randomized to one of three treatment groups: (1) control; (2) systemic intravenous chemotherapy; or (3) superselective intra-arterial chemotherapy. On completion of preoperative chemotherapy, all patients underwent operative exploration with curative intent. A total of 74 consecutive patients were found to be unresectable, as evidenced by the presence of liver metastasis, peritoneal carcinomatosis, enlarged retroperitoneal lymph nodes, or locally extensive disease not detected by preoperative CT scanning. The median survival time in the control group and after intravenous chemotherapy was only 91 and 96 days, respectively, as compared to 401 days in the patients receiving intra-arterial chemotherapy. The results confirmed that superselective intra-arterial chemotherapy conferred a highly significant survival advantage compared to control or systemic intravenous chemotherapy adjusted for all patient characteristics (P <0.0001).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma/tratamento farmacológico , Cuidados Paliativos , Neoplasias Gástricas/tratamento farmacológico , Adulto , Idoso , Carcinoma/patologia , Carcinoma/secundário , Carcinoma/cirurgia , Distribuição de Qui-Quadrado , Feminino , Seguimentos , Gastroscopia , Humanos , Injeções Intra-Arteriais , Injeções Intravenosas , Modelos Lineares , Neoplasias Hepáticas/secundário , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasias Peritoneais/secundário , Modelos de Riscos Proporcionais , Estudos Prospectivos , Estômago/irrigação sanguínea , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Taxa de Sobrevida , Tomografia Computadorizada por Raios X
13.
Stat Med ; 18(11): 1323-39, 1999 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10399199

RESUMO

Simon's optimal two-stage design is widely used to conduct single-dose phase II clinical trials. We extend this basic methodology to the situation where the researcher desires to test an experimental drug for activity at a low dose level, but is willing to increase the dose part-way through the trial if the early results suggest that the low dose is ineffective. Interest is confined to at most one dose escalation, and no consideration is given to escalating the dose within a patient. Optimal multi-stage designs are presented that are more efficient than the naive approach of merely conducting two consecutive Simon optimal trials, one at the low dose and the second (if deemed necessary) at the high dose. As in Simon's original design, toxicity is not considered here as a primary endpoint. Hence, the designs presented in this paper are appropriate only when the toxicity of the drug is well understood at both dose levels.


Assuntos
Ensaios Clínicos Fase II como Assunto/estatística & dados numéricos , Relação Dose-Resposta a Droga , Análise Numérica Assistida por Computador , Algoritmos , Antidepressivos/uso terapêutico , Apoptose/efeitos dos fármacos , Feminino , Fogachos/tratamento farmacológico , Humanos , Masculino , Neoplasias da Próstata/tratamento farmacológico , Tamanho da Amostra
14.
Am J Pathol ; 153(6): 1993-2006, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9846989

RESUMO

We have previously shown that fibroblast growth factor (FGF)-1-, FGF-4-, or vascular endothelial growth factor (VEGF/VPF)-transfected MCF-7 breast carcinoma cells growing as tumors in nude mice are tamoxifen resistant and/or estrogen independent. These transfectants provide opportunity for study of in situ tumor-induced angiogenesis promoted by the individual angiogenic factors under growth-promoting versus growth-inhibiting hormonal conditions. In the present study, vessels in tumors harvested at varying times after tumor cell injection were immunohistochemically highlighted and vessel morphology and topography were scored on a scale of 0 to 4 by blinded observers. In tumors produced by all cell lines under all growth-promoting hormonal conditions, there was significantly increased abundance (P < 0.05) of edge-associated and intratumor microvessels, but not of stromally located microvessels, when compared with tumor nodules harvested under growth-inhibiting conditions, regardless of the identity of the angiogenic factor or the hormonal treatment. Image analysis of bromodeoxyuridine (BrdU)-labeled nuclei of tumors produced by all cell lines under all hormonal conditions harvested at early time points showed that mean labeling indices were highest for hormonal conditions that produced the most robust growth in that particular cell line, implying that a high BrdU labeling index is a predictor of future tumor growth in individual tumors. These results confirm previous studies that established the importance of neovascularization for tumor growth and provide validation for use of these cell lines to study the process of angiogenesis in vivo. Study of gene expression in endothelial cells in edge-associated or intratumor vessels using this model might reveal mechanisms important in tumor-induced angiogenesis in human breast cancer.


Assuntos
Neoplasias da Mama/irrigação sanguínea , Carcinoma/irrigação sanguínea , Fatores de Crescimento Endotelial/fisiologia , Fatores de Crescimento de Fibroblastos/fisiologia , Regulação Neoplásica da Expressão Gênica , Linfocinas/fisiologia , Neovascularização Patológica/fisiopatologia , Animais , Neoplasias da Mama/genética , Bromodesoxiuridina , Carcinoma/genética , Modelos Animais de Doenças , Fatores de Crescimento Endotelial/genética , Fatores de Crescimento Endotelial/metabolismo , Estradiol/farmacologia , Feminino , Fatores de Crescimento de Fibroblastos/genética , Humanos , Imuno-Histoquímica , Inflamação , Linfocinas/genética , Linfocinas/metabolismo , Neoplasias Mamárias Experimentais/irrigação sanguínea , Camundongos , Camundongos Nus , Microcirculação/anatomia & histologia , Microcirculação/efeitos dos fármacos , Transplante de Neoplasias , Neovascularização Patológica/diagnóstico , Ovariectomia , Prognóstico , Tamoxifeno/farmacologia , Transfecção , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
15.
Clin Cancer Res ; 4(7): 1591-5, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9676831

RESUMO

To date, none of the potential biological markers in colorectal cancer attempts to link the epidemiological data with the molecular biology of the disease. In an attempt to link dietary and epidemiological factors and to obtain a better understanding of the molecular biology of colorectal cancer, we measured vitamin D receptor (VDR) expression in 75 human colorectal cancers as a potential predictive marker of the biological behavior of the disease. Our results showed that a high level of VDR expression was associated with a favorable prognosis. The results of the studies reinforce the potential role that VDR may play in the development of the pathogenesis of colorectal cancer. Larger studies looking exclusively at stage I and stage II disease will hopefully lead to the development of a sensitive hormonal marker that can be used to predict the biological behavior of colorectal cancer, identifying at-risk patients in need of adjuvant treatment.


Assuntos
Neoplasias Colorretais/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores de Calcitriol/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Prognóstico , Modelos de Riscos Proporcionais
16.
Biometrics ; 54(1): 136-47, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9544512

RESUMO

Suppose the number of 2 x 2 tables is large relative to the average table size, and the observations within a given table are dependent, as occurs in longitudinal or family-based case-control studies. We consider fitting regression models to the odds ratios using table-level covariates. The focus is on methods to obtain valid inferences for the regression parameters beta when the dependence structure is unknown. In this setting, Liang (1985, Biometrika 72, 678-682) has shown that inference based on the noncentral hypergeometric likelihood is sensitive to misspecification of the dependence structure. In contrast, estimating functions based on the Mantel-Haenszel method yield consistent estimators of beta. We show here that, under the estimating function approach, Wald's confidence interval for beta performs well in multiplicative regression models but unfortunately has poor coverage probabilities when an additive regression model is adopted. As an alternative to Wald inference, we present a Mantel-Haenszel quasi-likelihood function based on integrating the Mantel-Haenszel estimating function. A simulation study demonstrates that, in medium-sized samples, the Mantel-Haenszel quasi-likelihood approach yields better inferences than other methods under an additive regression model and inferences comparable to Wald's method under a multiplicative model. We illustrate the use of this quasi-likelihood method in a study of the familial risk of schizophrenia.


Assuntos
Modelos Estatísticos , Razão de Chances , Análise de Regressão , Biometria , Feminino , Humanos , Funções Verossimilhança , Modelos Logísticos , Masculino , Fatores de Risco , Esquizofrenia/genética
17.
Cancer Res ; 58(2): 352-61, 1998 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9443417

RESUMO

To determine the extent to which autocrine effects of acidic fibroblast growth factor (FGF)-1 overexpression contribute to an increased malignant phenotype, FGF-1-transfected MCF-7 cells were retransfected with a FGF receptor (FGFR1) vector encoding a truncated dominant-negative receptor to inhibit autocrine FGF signal transduction. This transfection eliminated FGF signaling within the breast cancer cells without interfering with their ability to produce FGF-1, thereby allowing possible paracrine effects to still be observed in vivo. Truncated FGFR1 overexpression inhibited the acquired ability of FGF-1-overexpressing cells to form colonies in soft agar in estrogen-depleted or antiestrogen-containing medium. However, soft agar colony formation was still stimulated by estrogen treatment in cells expressing up to 6 x 10(5) truncated FGFR1 sites per cell. In vivo, truncated receptor expression severely inhibited the ability of the FGF-1-overexpressing cells to form tumors without estrogen in ovariectomized mice, indicating that the mitogenic effect of FGF-1 on the breast tumor cells was important in the estrogen-independent in vivo growth of these transfectants. However, rapid formation of large tumors was still observed in estrogen-supplemented mice injected with the truncated FGFR1-expressing cells, suggesting that the paracrine effects of FGF production could act in synergy with mitogenic effects mediated by estrogen. Truncated FGFR1-overexpressing cells also continued to form tumors in tamoxifen-treated mice, raising the possibility that the paracrine effects of FGF-1 expression may allow the partial agonist properties of this antiestrogen to be more readily observed. We conclude that autocrine effects of FGF-1 increase the ability of MCF-7 breast cancer cells to grow in vitro and in vivo under estrogen-depleted conditions but that paracrine effects of FGF-1 are also involved in the enhancement of tumor growth in estrogen-supplemented or tamoxifen-treated animals.


Assuntos
Comunicação Autócrina/fisiologia , Neoplasias da Mama/patologia , Antagonistas de Estrogênios/farmacologia , Estrogênios/fisiologia , Fator 1 de Crescimento de Fibroblastos/metabolismo , Comunicação Parácrina/fisiologia , Receptores Proteína Tirosina Quinases , Tamoxifeno/farmacologia , Animais , Northern Blotting , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Divisão Celular/efeitos dos fármacos , Primers do DNA/química , Resistencia a Medicamentos Antineoplásicos , Estrogênios/farmacologia , Feminino , Fator 1 de Crescimento de Fibroblastos/genética , Vetores Genéticos , Humanos , Camundongos , Camundongos Nus , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , RNA Mensageiro/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Transfecção , Células Tumorais Cultivadas
18.
Breast Cancer Res Treat ; 52(1-3): 175-84, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10066081

RESUMO

IGF1 and IGF2 are circulating peptide hormones and locally-acting growth factors with both paracrine and autocrine functions. IGF1 and IGF2 signal through a common tyrosine kinase receptor, the insulin-like growth factor 1 receptor (IGF1R), and have mitogenic, cell survival, and insulin-like actions that are essential for embryogenesis, post-natal growth physiology, and breast development. The activities of IGF1 and 2 are tightly-regulated by a network of binding proteins and targeted degradation mechanisms. This complex regulatory system is disrupted in breast cancer, leading to excess IGF1R signaling. Evidence for this statement includes: a) breast cancers are infiltrated with IGF2 expressing stromal cells; b) mannose 6-phosphate/IGF2 receptor (M6P/IGF2R) is mutated in breast cancer, leading to loss of IGF2 degradation; c) IGF1R is overexpressed by malignant breast epithelial cells, and in some cases IGF1R is amplified; and d) complex changes in IGF binding protein expression occur during breast cancer progression which most likely also affect IGF1 and 2 signaling. The clinical importance of these epigenetic and genetic changes has recently been stressed by the finding that IGF1R signaling alters the apoptotic response of breast cancer cells to genotoxic stress and, in addition, IGF1R activation sensitizes cells to estrogen by inducing phosphorylation of the estrogen receptor. As a consequence of these findings, we propose that IGF analysis of breast cancer samples should shift from prognostic studies to an evaluation of IGF ligands, receptors, and binding proteins as resistance/sensitivity markers for radiation, chemotherapy, and endocrine therapy.


Assuntos
Neoplasias da Mama/química , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/análise , Receptor IGF Tipo 1/análise , Receptor IGF Tipo 2/análise , Somatomedinas/análise , Apoptose , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Feminino , Humanos , Prognóstico
19.
Oncogene ; 15(17): 2093-108, 1997 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-9366526

RESUMO

FGF-1 is expressed in a high proportion of breast tumors. While overexpression of FGF-4 in the MCF-7 breast carcinoma cell line confers the ability to form spontaneously metastasizing tumors in ovariectomized nude mice without estrogen supplementation and in mice that receive tamoxifen pellets, the response of a cell to individual FGFs can be controlled at multiple levels, and the significance of FGF-1 expression in human breast tumors is uncertain. To study the role of FGF-1, MCF-7 human breast cancer carcinoma cells, previously transfected with bacterial beta-galactosidase, were retransfected with FGF-1 expression vectors. FGF-1 transfectants formed large, vascularized tumors in ovariectomized nude mice without estrogen supplementation as well as in mice that received tamoxifen pellets. Lymphatic and pulmonary micrometastases were detected as deposits of X-gal-stained cells as early as 17 days after cell inoculation whereas no metastases were detected in estrogen-supplemented mice bearing similar-sized control tumors. When compared with controls, both clonal and polyclonal populations of FGF-1 overexpressing cells exhibited increased anchorage-independent growth and decreased population doubling times in estrogen-depleted or 4-hydroxytamoxifen containing medium. These results suggest that FGF signaling may be important in the transition of breast cancer cells from hormone-dependent to hormone-independent and from nonmetastatic to metastatic.


Assuntos
Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/patologia , Carcinoma/irrigação sanguínea , Carcinoma/secundário , Antagonistas de Estrogênios/farmacologia , Fator 1 de Crescimento de Fibroblastos/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Hormônio-Dependentes/metabolismo , Neovascularização Patológica/etiologia , Ovariectomia , Tamoxifeno/farmacologia , Animais , Permeabilidade Capilar , Adesão Celular , Divisão Celular/efeitos dos fármacos , Feminino , Fator 1 de Crescimento de Fibroblastos/genética , Vetores Genéticos , Humanos , Neoplasias Pulmonares/secundário , Metástase Linfática , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Neoplasias Hormônio-Dependentes/genética , Fenótipo , RNA Mensageiro/metabolismo , Transfecção , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
20.
Int J Radiat Oncol Biol Phys ; 38(4): 797-804, 1997 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-9240649

RESUMO

PURPOSE: A subset of 362 pediatric patients with rhabdomyosarcoma was selected from a total of 532 eligible IRS-II patients in Clinical Group III to assess the local and regional failure rates following radiotherapy and to determine patient, tumor, and treatment factors contributing to the risk for local and regional failure. METHODS AND MATERIALS: The study population was selected from all eligible IRS-II Clinical Group III patients. Excluded patients were those with "special pelvic" primary sites whose protocol management restricted radiotherapy (n = 123), and those who were removed from the study before radiotherapy was to begin, or because it was omitted (n = 47). A binary recursive partitioning model was used to identify subgroups of the remaining 362 patients at risk of local or regional failure. RESULTS: The local (only) failure rate was 17% (95% confidence interval, 13-21%), and the local (all) failure rate was 20% (95% confidence interval, 16-24%). The 5-year actuarial risk of local (all) failure was 22% (95% confidence interval, 18-27%). The risk of regional (nodal) failure was between 2% and 23%. Increasing tumor size predicted an increased local failure risk. Primary tumors located above the clavicle had a reduced risk of local failure. The binary recursive partitioning model identified a subset of patients at high risk of local failure. Those patients had primary tumors in the chest, pelvic region, extremity, or trunk, or tumors > 10 cm in diameter. Their local failure rate was 35% (compared to 15% for the remaining patients). The subset of patients at high risk for regional (nodal) failure had node involvement at diagnosis and a primary tumor originating at a site other than orbit, parameningeal, or trunk. Compliance with radiation treatment guidelines approached but did not achieve statistical significance as a predictive factor for local failure. By univariate analysis, factors not influencing local failure risk were age, race, gender, adenopathy, and histology. CONCLUSION: Radiation therapy and chemotherapy administered to Clinical Group III patients entered into the IRS-II protocol produced sustained local control in most cases. Knowledge of the factors which predict an increased risk of local or regional failure will facilitate the design of new treatment strategies.


Assuntos
Rabdomiossarcoma/radioterapia , Adulto , Análise de Variância , Intervalos de Confiança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Rabdomiossarcoma/patologia , Falha de Tratamento
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