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1.
Cell Mol Life Sci ; 64(21): 2848-57, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17928951

RESUMO

Extracts of Cimicifuga racemosa are used frequently for menopausal complaints. Cimicifuga is well tolerated but can occasionally cause liver injury. To assess hepatotoxicity of cimicifuga in more detail, ethanolic C. racemosa extract was administered orally to rats, and liver sections were analyzed by electron microscopy. Tests for cytotoxicity, mitochondrial toxicity and apoptosis/necrosis were performed using HepG2 cells. Mitochondrial toxicity was studied using isolated rat liver mitochondria. Microvesicular steatosis was found in rats treated with > 1,000 mg/kg [DOSAGE ERROR CORRECTED] body weight cimicifuga extract. In vitro, cytotoxicity was apparent at concentrations > or =75 microg/mL, and mitochondrial beta-oxidation was impaired at concentrations > or =10 microg/mL. The mitochondrial membrane potential was decreased at concentrations > or =100 microg/mL, and oxidative phosphorylation was impaired at concenq trations > or =300 microg/mL. The mechanism of cell death was predominantly apoptosis. C. racemosa exerts toxicity in vivo and in vitro, eventually resulting in apoptotic cell death. The results are compatible with idiosyncratic hepatotoxicity as observed in patients treated with cimicifuga extracts.


Assuntos
Cimicifuga/toxicidade , Fígado/efeitos dos fármacos , Extratos Vegetais/toxicidade , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Feminino , Humanos , Técnicas In Vitro , Fígado/lesões , Fígado/metabolismo , Fígado/patologia , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Ratos , Ratos Sprague-Dawley , Ratos Wistar
2.
Breast Cancer Res Treat ; 67(3): 223-33, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11561768

RESUMO

The purpose of this study was to analyze the drug interactions of paclitaxel (PTX) with epirubicin (EPI), carboplatin (CBDCA), gemcitabine (GEM) and vinorelbine (VIN) in human breast cancer cells and compare the cytotoxic activity of each drug combination in primary breast cancer samples. These experiments were intended to identify the most active agents in combination with PTX, and to provide a preclinical rational for future clinical investigations in breast cancer. Multiple drug effect/combination index (CI) isobologram analysis was applied to combinations of PTX with either CBDCA, EPI, GEM or VIN in MCF-7, MDA-MB-231 and SK-BR-3 human breast cancer cell lines. Drug concentrations were limited to the ranges achievable in humans in vivo, and the drugs were applied simultaneously at fixed molar ratios for each drug combination. Interactions were assessed at multiple effect levels (IC10-IC90). Additionally, the cytotoxic activity of these combinations was assessed in tumor samples of 50 primary breast cancer patients, utilizing the ATP-tumorchemosensitivity assay (ATP-TCA). Drug interactions were shown to be strongly dose-related in the human breast cancer cell lines investigated. At clinically relevant concentrations, CBDCA/PTX demonstrated synergistic (MCF-7) or additive (MDA-MB-231, SK-BR-3) interactions, and EPI/PTX showed additive (SK-BR-3, MCF-7) and antagonistic (MDA-MB-231) interactions. GEM/PTX and VIN/PTX, however, demonstrated antagonism over multiple dose effect levels at clinically relevant drug concentrations in all three cell lines tested. At plasma peak concentrations, EPI/PTX, CBDCA/PTX, GEM/PTX and VIN/PTX achieved > or = 90% tumor growth inhibition in 93, 86, 63 and 50%, respectively, of primary breast cancer samples investigated with the ATP-TCA. Cumulative dose-response plots of primary breast cancer tumor cells responding in vitro with > or = 90% growth inhibition showed a strong dose dependence for both EPI/PTX and CBDCA/PTX. In conclusion, the current data indicate favorable drug interactions for CBDCA/PTX at clinically relevant drug concentrations in breast cancer cells, and demonstrate superior in vitro cytotoxicity of EPI/PTX and CBDCA/PTX compared to GEM/PTX and VIN/PTX in primary breast cancer cultures.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/patologia , Desoxicitidina/análogos & derivados , Paclitaxel/farmacologia , Vimblastina/análogos & derivados , Antineoplásicos/farmacocinética , Antineoplásicos Fitogênicos/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Carboplatina/farmacocinética , Carboplatina/farmacologia , Desoxicitidina/farmacocinética , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Ensaios de Seleção de Medicamentos Antitumorais , Epirubicina/farmacocinética , Epirubicina/farmacologia , Feminino , Humanos , Paclitaxel/farmacocinética , Células Tumorais Cultivadas , Vimblastina/farmacocinética , Vimblastina/farmacologia , Vinorelbina , Gencitabina
3.
Clin Cancer Res ; 7(8): 2448-57, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11489825

RESUMO

PURPOSE: Recent studies suggest that HER-2/neu specifically promotes the invasive capacity of tumor cells by up-regulating secretion of the proteolytic enzyme, urokinase-type plasminogen activator (uPA), or its inhibitor, plasminogen activator inhibitor-1 (PAI-1), in colon and gastric cancer. It was the purpose of this study to: (a) evaluate the association between HER-2/neu and uPA and PAI-1 expression in a large primary breast cancer cohort; (b) perform the first multivariate analysis, including HER-2/neu, uPA, and PAI-1 in breast cancer; and (c) define the effect of HER-2/neu overexpression on uPA and PAI-1 expression in breast cancer cells. EXPERIMENTAL DESIGN: HER-2/neu, uPA, and PAI-1 were measured as continuous variables by ELISA in primary breast cancer tissue extracts from 587 patients with clinical follow-up and analyzed for correlations with clinical outcome. Furthermore, a full-length human HER-2/neu cDNA was introduced into five human breast cancer cell lines to define the effects of HER-2/neu overexpression on uPA and PAI-1 expression. In addition, we tested whether HER-2/neu antibodies could reverse any given alteration of uPA and PAI-1 levels. RESULTS: Our findings indicate a weak positive association between HER-2/neu and uPA (r = 0.147; P < 0.001) and no association between HER-2/neu and PAI-1 (r = 0.07; P = 0.085). HER-2/neu overexpression (> or =400 fmol/mg) and high levels of uPA/PAI-1 (> or =5.5 ng/mg and/or > or =14 ng/mg, respectively) were significantly associated with shorter disease-free survival (DFS; P < 0.001 and P = 0.003) and metastasis-free survival (MFS; P = 0.015 and P < 0.001). Multivariate analysis revealed prognostic independence between HER-2/neu and the uPA/PAI-1 axis for DFS and MFS. Both uPA and PAI-1 had no significant discriminatory effect among HER-2/neu-positive patients for DFS. The prognostic value of HER-2/neu overexpression for MFS, however, was significantly enhanced by elevated uPA expression (P = 0.053). Stable transfection of the HER-2/neu gene into multiple human breast cancer cell lines resulted in consistent down-regulation of uPA or PAI-1 expression. In addition, anti-HER-2/neu antibodies did not significantly affect uPA or PAI-1 expression in human cancer cell lines naturally overexpressing HER-2/neu. CONCLUSIONS: The present findings suggest that the invasive phenotype elicited by HER-2/neu overexpression in breast cancer is not a direct effect of uPA or PAI-1 expression. HER-2/neu and the uPA/PAI-1 axis have been shown to affect the invasive capacity of breast cancer independently. Determination of uPA can provide significant additional prognostic information for MFS in HER-2/neu-positive and -negative patients.


Assuntos
Neoplasias da Mama/patologia , Inibidor 1 de Ativador de Plasminogênio/análise , Receptor ErbB-2/análise , Ativador de Plasminogênio Tipo Uroquinase/análise , Adulto , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Intervalo Livre de Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Vetores Genéticos/genética , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Metástase Neoplásica , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Receptor ErbB-2/genética , Retroviridae/genética , Trastuzumab , Células Tumorais Cultivadas
4.
Breast Cancer Res Treat ; 69(1): 53-63, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11759828

RESUMO

Available clinical and experimental data on the effect of HER-2/neu overexpression on chemosensitivity are controversial. It was the purpose of this in vitro study to define the association between HER-2/neu overexpression and the sensitivity to the chemotherapeutic drug combinations of cyclophosphamide, methotrexate and 5-fluorouracil (CMF) and 5-fluorouracil, epirubicin and cyclophosphamide (FEC) of breast cancer cells derived from 140 chemotherapy-naïve patients at the time of primary surgery. Both drug combinations were tested at six different concentrations ranging from 6.25-200% peak plasma concentration (PPC). Immunohistochemical detection of HER-2/neu overexpression was performed with the HER-2/neu antibodies, CB11, TAB250 and AO485, in the same tumor specimens. Immunoreactions were determined as negative (0/1+), weakly positive (2+) and strongly positive (3+). However, the antibodies varied in their degrees of sensitivity. Breast cancer samples with strong (3+) HER-2/neu overexpression demonstrated 90% growth inhibition (IC90) at significantly lower PPC values, using the CB11 (p = 0.048), TAB250 (p = 0.007) and AO485 (p < or =0.01) antibodies, and showed 50% growth inhibition (IC50) at significantly lower PPC values, using the CB11 antibody (p = 0.01) compared to their counterparts with lower levels of HER-2/neu expression. When analyzing the group of patients with intermediate and strong HER-2/neu overexpression (2+ and 3+), an association between HER-2/neu overexpression and increased chemosensitivity was seen with the TAB250 (p = 0.044) and AO485 (p = 0.032) antibodies, but not with the CB11 antibody (p =0.8) at the IC90 level. Differences in chemosensitivity between samples with strong HER-2/neu overexpression and those with lower levels were then analyzed separately for CMF and FEC. Both regimens achieved 90% tumor growth inhibition at lower PPC values in samples with strong HER-2/neu overexpression (3+) compared to their counterparts with lower expression levels (AO485 p = 0.011 for CMF, and p = 0.09 for FEC). Cumulative concentration-response plots of tumors responding in vitro with 90% tumor cell inhibition showed a stronger dose dependence for both CMF and FEC among tumor samples with strong HER-2/neu overexpression compared to those with lower levels of expression. In conclusion, the data show that HER-2/neu overexpression was not associated with in vitro drug resistance to CMF or FEC. In contrast, tumors with strong HER-2/neu overexpression demonstrated increased dose-dependent in vitro sensitivity to both the FEC and CMF regimens.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica , Receptor ErbB-2/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/patologia , Ciclofosfamida/administração & dosagem , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Epirubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Imuno-Histoquímica , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Regulação para Cima
5.
Gynecol Oncol ; 77(2): 258-63, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10785475

RESUMO

OBJECTIVE: Our purpose was to: (a) study the in vitro chemosensitivity of primary epithelial ovarian cancer to drug combinations with cisplatin (CDDP), carboplatin (CBDCA), paclitaxel (PTX), epirubicin (EPI), or cyclophosphamide (CTX) utilizing the ATP tumorchemosensitivity assay (ATP-TCA); (b) correlate the test results with clinical response in patients with FIGO stage III ovarian cancer; and (c) analyze the most useful parameters for interpretation of test results. METHODS: CBDCA/CTX, CBDCA/PTX, CDDP/PTX, and EPI/PTX were tested in 93 fresh human primary epithelial ovarian cancer specimens. Correlations of in vitro drug sensitivity/resistance and clinical response were performed in 38 patients with FIGO stage III disease utilizing Fisher's exact test and by comparison of progression-free (PFS) and overall survival (OS) between those testing as sensitive or resistant. A progression-free interval of more than 12 months following surgery was classified as clinical response. ATP-TCA results were analyzed using the median effective dose, area under the curve, or a defined sensitivity index. RESULTS: Evaluable test results were achieved in 83 of 93 patients (89%). EPI/PTX had the highest in vitro activity (P < 0.001). In the clinical correlation, 29 of 38 patients (76%) were classified as in vitro sensitive (sensitivity index [SI] <250) and 9 patients as in vitro resistant (SI >250). The SI was superior for interpretation of test results. Patients testing as chemosensitive had a significantly longer mean PFS (28.5 vs 12.6 months, P = 0.033) and OS (46.1 vs 17.6, P = 0.03) compared to those patients predicted to be resistant. The assay demonstrated a sensitivity, specificity, and positive and negative predictive value of 95, 44, 66, and 89%, respectively (Fisher's exact test, P = 0. 007). CONCLUSION: The observed in vitro efficacy of EPI/PTX in primary epithelial ovarian cancer specimens warrants further clinical evaluation. The high evaluability rate and the observed correlation with PFS and OS, within the limitations of a nonrandomized study, support the use of the ATP chemosensitivity assay in future prospective assay-directed trials.


Assuntos
Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma/tratamento farmacológico , Carcinoma/patologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Trifosfato de Adenosina/sangue , Carboplatina/farmacologia , Cisplatino/farmacologia , Ciclofosfamida/farmacologia , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Epirubicina/farmacologia , Feminino , Humanos , Paclitaxel/farmacologia , Valor Preditivo dos Testes , Análise de Regressão , Sensibilidade e Especificidade , Análise de Sobrevida , Células Tumorais Cultivadas
6.
J Clin Microbiol ; 34(5): 1327-9, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8727933

RESUMO

A total of 6,010 blood culture sets were obtained from adult patients with suspected bacteremia or fungemia. The overall recovery of organisms was equivalent in two systems used, BacT/Alert FAN medium and BACTEC NR660 Plus 26A medium.


Assuntos
Técnicas Bacteriológicas , Meios de Cultura , Micologia/métodos , Adulto , Bacteriemia/diagnóstico , Erros de Diagnóstico , Estudos de Avaliação como Assunto , Fungemia/diagnóstico , Humanos
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