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1.
Lab Med ; 54(5): 512-518, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36810591

RESUMO

Massive-scale SARS-CoV-2 testing using the SwabSeq diagnostic platform came with quality assurance challenges due to the novelty and scale of sequencing-based testing. The SwabSeq platform relies on accurate mapping between specimen identifiers and molecular barcodes to match a result back to a patient specimen. To identify and mitigate mapping errors, we instituted quality control using placement of negative controls within a rack of patient samples. We designed 2-dimensional paper templates to fit over a 96-position rack of specimens with holes to show the control tube placements. We designed and 3-dimensionally printed plastic templates that fit onto 4 racks of patient specimens and provide accurate indications of the correct control tube placements. The final plastic templates dramatically reduced plate mapping errors from 22.55% in January 2021 to less than 1% after implementation and training in January 2021. We show how 3D printing can be a cost-effective quality assurance tool to mitigate human error in the clinical laboratory.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Teste para COVID-19 , Sequenciamento de Nucleotídeos em Larga Escala , Impressão Tridimensional , Plásticos
2.
Int J Cancer ; 122(8): 1905-10, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18076071

RESUMO

Nitroxyl (HNO) can inhibit the glycolytic enzyme glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Because of the importance of glycolysis in many malignant cells, we thus propose that HNO can adversely affect tumor growth. This hypothesis was tested using in vitro and in vivo models of breast cancer. We report here for the first time that HNO suppresses the proliferation of both estrogen receptor (ER)-positive and ER-negative human breast cancer cell lines, in a dose dependent manner. Mice treated with HNO either injected into the tumor itself or via the intraperitoneal approach had smaller xenograft tumor size. In addition to significantly decreased blood vessel density in the HNO-treated tumors, we observed lower levels of circulating serum vascular endothelial growth factor (VEGF). Accordingly, there was a decrease in total HIF-1alpha (hypoxia-inducible factor) protein in HNO-treated tumor cells. Further studies showed inhibition of GAPDH activity in HNO-treated human breast cancer cell lines and in HNO-treated tumor tissue derived from xenografts. One explanation for the multiplicity of actions observed after HNO treatment could be the effect from the initial inhibition of GAPDH, providing a potential therapeutic avenue based upon blocking glycolysis resulting in decreased HIF-1alpha, thus leading to angiogenesis inhibition. Therefore, HNO appears to act via mechanism(s) different from those of existing breast cancer drugs, making it a potential candidate to overcome known and emerging drug resistance pathways.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Inibidores Enzimáticos/farmacologia , Gliceraldeído-3-Fosfato Desidrogenases/antagonistas & inibidores , Glicólise/efeitos dos fármacos , Óxidos de Nitrogênio/farmacologia , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Feminino , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos SCID , Nitritos/farmacologia , Transplante Heterólogo , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo
3.
Int J Oncol ; 32(2): 475-80, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18202771

RESUMO

Angiogenesis is critical to tumor growth and is stimulated by tissue hypoxia due to poor oxygen delivery. In turn, cellular hypoxia leads to angiogenesis via the induction of hypoxia-inducible factor-1alpha (HIF-1alpha) and vascular endothelial growth factor (VEGF) at a cellular level. Pomegranate juice and extracts, which are rich sources of ellagitannins, have been shown to have chemopreventive potential against prostate cancer, but there have been no studies on the effects of an ellagitannin-rich pomegranate extract on angiogenesis. Human prostate cancer cells (LNCaP) and human umbilical vein endothelial cells (HUVEC) were incubated with a pomegranate extract standardized to ellagitannin content (POMx), under normoxic and hypoxic conditions in vitro. Human prostate cancer cells (LAPC4) were injected subcutaneously into severe combined immunodeficient (SCID) mice and the effects of oral administration of POMx on tumor growth, microvessel density, and HIF-1alpha and VEGF expression were determined after 4 weeks of treatment. POMx inhibited the proliferation of LNCaP and HUVEC cells significantly under both normoxic and hypoxic conditions. HIF-1alpha and VEGF protein levels were also reduced by POMx under hypoxic conditions. POMx decreased prostate cancer xenograft size, tumor vessel density, VEGF peptide levels and HIF-1alpha expression after 4 weeks of treatment in SCID mice. These results demonstrate that an ellagitannin-rich pomegranate extract can inhibit tumor-associated angiogenesis as one of several potential mechanisms for slowing the growth of prostate cancer in chemopreventive applications. Further studies in humans are needed to confirm that angiogenesis can be inhibited by an ellagitannin-rich pomegranate extract administered orally as a dietary supplement.


Assuntos
Regulação Neoplásica da Expressão Gênica , Taninos Hidrolisáveis/metabolismo , Lythraceae/metabolismo , Neovascularização Patológica , Extratos Vegetais/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Administração Oral , Animais , Linhagem Celular Tumoral , Humanos , Hipóxia , Técnicas In Vitro , Masculino , Camundongos , Camundongos SCID , Transplante de Neoplasias
4.
Cancer Res ; 65(14): 6159-66, 2005 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16024617

RESUMO

We recently discovered a novel gene and named it endothelial-derived gene 1 (EG-1). Previously, we have shown that the expression of EG-1 is significantly elevated in the epithelial cells of breast cancer, colorectal cancer, and prostate cancer. Here, we report that EG-1 can stimulate cellular proliferation. Transfection experiments which overexpressed the full-length EG-1 gene in human embryonic kidney HEK-293 cells or human breast cancer cell lines resulted in significantly increased in vitro proliferation, in comparison with transfection with empty vectors. On the other hand, small interfering RNA cotransfection resulted in inhibition of proliferation. S.c. xenograft assays were carried out in a severe combined immunodeficient mouse model. We found that injection of high EG-1 expressing HEK-293 clones resulted in significantly larger tumors, in comparison with clones carrying the empty vectors. To further clarify the function of this gene, we investigated its interaction with Src and members of the mitogen-activated protein kinase (MAPK) family. Immunoprecipitation with anti-Src antibody, followed by immunoblotting with anti-EG-1 antibody, showed an association between these two molecules. Overexpression of EG-1 was correlated with activation of the following kinases: extracellular signal-regulated kinases 1 and 2, c-jun-NH2-kinase, and p38. These observations collectively support the hypothesis that the novel gene EG-1 is a positive stimulator of cellular proliferation, and may possibly be involved in signaling pathways involving Src and MAPK activation.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteínas/fisiologia , Sequência de Aminoácidos , Animais , Neoplasias da Mama/enzimologia , Neoplasias da Mama/metabolismo , Proteína Tirosina Quinase CSK , Processos de Crescimento Celular/genética , Linhagem Celular Tumoral , Ativação Enzimática , Feminino , Humanos , Sistema de Sinalização das MAP Quinases , Complexo Mediador , Camundongos , Camundongos SCID , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Dados de Sequência Molecular , Transplante de Neoplasias , Fragmentos de Peptídeos/genética , Fosfotransferases/metabolismo , Proteínas Tirosina Quinases , Proteínas/antagonistas & inibidores , Proteínas/genética , Proteínas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Transplante Heterólogo , Quinases da Família src
5.
Int J Oncol ; 29(4): 1013-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16964398

RESUMO

EG-1 is significantly elevated in breast, colorectal, and prostate cancers. Overexpression of EG-1 stimulates cellular proliferation, and targeted inhibition blocks mouse xenograft tumor growth. To further clarify the function of EG-1, we investigated its role in c-Src activation. We observed that EG-1 overexpression results in activation of c-Src, but found no evidence that EG-1 is a direct Src substrate. EG-1 also binds to other members of the Src family. Furthermore, EG-1 shows interaction with multiple other SH3- and WW-containing molecules involved in various signaling pathways. These observations suggest that EG-1 may be involved in signaling pathways including c-Src activation.


Assuntos
Neoplasias/enzimologia , Proteínas/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Domínios de Homologia de src , Linhagem Celular Tumoral , Ativação Enzimática , Humanos , Complexo Mediador , Mapeamento de Interação de Proteínas , Estrutura Terciária de Proteína , Transdução de Sinais , Ativação Transcricional
6.
Cancer Epidemiol Biomarkers Prev ; 14(12): 2995-8, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16365024

RESUMO

PURPOSE: It has been shown that early detection of breast cancer could save lives. Recently, there has been increasing interest in nipple fluid as a potential supplemental avenue for breast cancer diagnosis. EXPERIMENTAL DESIGN: In this study, we determined the levels of an angiogenic factor basic fibroblast growth factor (bFGF) in the nipple fluid of healthy subjects as well as patients with benign breast conditions, those at high risk for breast cancer, and patients with active breast cancer. ELISAs were used to measure bFGF. RESULTS: Nipple fluid bFGF levels were as follows (mean +/- SE): 158 +/- 17 pg/mL from benign breasts, 561 +/- 277 pg/mL from high-risk breasts, and 1,343 +/- 441 pg/mL from cancerous breasts. One-way ANOVA showed that the bFGF levels from cancerous breasts were significantly higher than those from benign and high-risk breasts (P = 0.0001 and P = 0.0193, respectively). After logarithmic transformation was applied to the data, high-risk breast bFGF levels were higher than those from benign breasts (P = 0.0028). With a cutoff level of 250 pg/mL, the sensitivity was 79.2%, specificity was 82.5%, and correct diagnosis was 66.4%. The area under the receiver operating characteristic curve was 0.86. CONCLUSIONS: We conclude that nipple fluid bFGF levels are progressively elevated in high-risk and cancerous breasts compared with benign breasts. The sensitivity and specificity of this test are promising compared with current breast cancer screening methods, and this test deserves further studies with larger clinical trials. Potential areas of usefulness include the detection of breast cancer risk or breast cancer, as well as the monitoring and/or prediction of the antiangiogenic effect of preventive therapies.


Assuntos
Biomarcadores Tumorais/análise , Líquidos Corporais/química , Neoplasias da Mama/diagnóstico , Fator 2 de Crescimento de Fibroblastos/análise , Mamilos , Adulto , Análise de Variância , Área Sob a Curva , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Sensibilidade e Especificidade , Estatísticas não Paramétricas
7.
Int J Oncol ; 26(1): 121-7, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15586232

RESUMO

Investigators have shown that PC-SPES is a potent herbal mixture which has often been used by prostate cancer patients. In this study, we examined the inhibitory effects of certain individual components of PC-SPES on the in vitro proliferation of the human breast cancer cells MDA-MB231 and the human umbilical vein endothelial cells (HUVEC). Our data showed that individual components of PC-SPES had varying suppressive effects on cellular proliferation, and that Rabdosia rubescens appeared to be the most potent agent in these assays. Apoptosis was up-regulated by Rabdosia rubescens, as seen in the caspase-9 and TUNEL assays. These effects may be mediated via both the MAPK (mitogen-activated protein kinase) and the Akt kinase pathways. In mouse experiments, the extract from Rabdosia rubescens suppressed breast cancer xenograft size and decreased the tumor vessel density. We conclude that Rabdosia rubescens may potentially be used to treat or prevent breast cancer, and that the extract from this herbal source deserves further studies.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Isodon/química , Neovascularização Patológica/tratamento farmacológico , Animais , Apoptose , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Feminino , Humanos , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neovascularização Patológica/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Int J Oncol ; 25(1): 193-202, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15202006

RESUMO

Green tea may prevent cancer, partially by inhibiting tumor angiogenesis. Our previous studies showed that green tea extract was effective in inhibiting breast cancer and endothelial cell proliferation in vitro, and suppressed xenograft size and decreased the tumor vessel density in vivo. Here, we set out to further investigate the molecular mechanisms of this observed angiogenesis suppression. We utilized cDNA microarray technology to profile the global changes in endothelial cellular gene expression in response to green tea. HUVEC (human umbilical vein endothelial cells) were exposed in vitro to green tea for either 6 or 48 h. Only statistically significantly differentially expressed genes were analyzed. Gene profiling demonstrated a global down-regulation of multiple genes involved in endothelial cell growth, signal transduction and oxidation, accompanied by up-regulation of several apoptotic genes. We validated these observations by showing positive correlations with biological assays of cellular proliferation, cell cycle, and apoptosis. The anti-oxidant characteristics of green tea and its metabolites were confirmed in the ORAC (oxygen radical absorbance capacity) assay. cDNA microarray revealed that green tea has an overall suppressive effect on multiple pathways in endothelial cells. This study contributes to the comprehensive analysis of the molecular effects of green tea on endothelial cells, and provides insight into genes that may be important in chemoprevention.


Assuntos
Endotélio Vascular/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Extratos Vegetais/farmacologia , Chá , Apoptose , Divisão Celular , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Fenótipo , Veias Umbilicais
9.
Int J Oncol ; 21(3): 487-91, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12168090

RESUMO

Investigators have shown that green tea may decrease the risk of cancer. It is widely accepted that the main active component of green tea is EGCG (epigallocatechin-3-gallate). In our previous study, we examined the effect of green tea on breast cancer growth and endothelial cells both in in vitro assays and in animal models. Our data show that both mixed green tea extract (GTE) as well as its individual catechin components are effective in inhibiting breast cancer and endothelial cell proliferation in vitro, and that GTE suppresses breast cancer xenograft size and decreases the tumor blood vessel density in vivo. In the present study, we further demonstrate that 40 microg/ml GTE or EGCG can decrease the levels of the angiogenic factor bFGF (basic fibroblast growth factor) levels in the cells. This phenomenon is observed in both human umbilical vein endothelial cells (HUVECs) and in human breast cancer cells MDA-MB231. This effect is dose dependent. Furthermore, GTE and EGCG decrease the transcript levels of bFGF and aFGF (acidic fibroblast growth factor) in HUVECs and MDA-MB231 cells. Our findings suggest that the inhibition of the angiogenic fibroblast growth factors could account for one of the mechanisms of green tea's actions. Since cancer is angiogenesis dependent, this may partially explain the antineoplastic effects associated with green tea consumption.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Catequina/análogos & derivados , Catequina/farmacologia , Fator 2 de Crescimento de Fibroblastos/antagonistas & inibidores , Chá/química , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Células Cultivadas , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Fator 1 de Crescimento de Fibroblastos/antagonistas & inibidores , Fator 1 de Crescimento de Fibroblastos/genética , Fator 1 de Crescimento de Fibroblastos/metabolismo , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Humanos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Extratos Vegetais/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
Oncol Rep ; 12(3): 659-62, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15289852

RESUMO

This study was conducted to investigate the anti-proliferative activities of medicinal mushroom Ganoderma lucidum (Rei-shi or Mannentake). We have identified an alcohol extract from the spore of Ganoderma lucidum that inhibits the in vitro proliferation of human umbilical vein endothelial cells and MDA-MB231 human breast cancer cells. Further fractionation of the alcohol extract revealed that the ethyl acetate fraction inhibited both cell lines in a dose-dependent manner from 2 to 40 micro g/ml. Our results suggest that the alcohol extract from the spore of Ganoderma lucidum may possess potential anti-tumor and anti-angiogenic activities.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Extratos Vegetais/uso terapêutico , Reishi/metabolismo , Inibidores da Angiogênese/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias da Mama/patologia , Divisão Celular , Linhagem Celular Tumoral , Células Cultivadas , Cromatografia , Relação Dose-Resposta a Droga , Células Endoteliais/citologia , Etanol/farmacologia , Humanos , Técnicas In Vitro , Esporos Fúngicos/metabolismo , Veias Umbilicais/citologia
11.
Anticancer Res ; 23(1A): 231-4, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12680218

RESUMO

BACKGROUND: Within the last decade, there has been much interest in the area of tumor angiogenesis, with the advent of many new anti-angiogenic drugs undergoing testing in cancer clinical Phases II and III. Many of the cancer patients also take multiple medications for a variety of chronic illnesses. Because of possible drug-drug interactions, it is important to investigate the effect that commonly prescribed medications may have on angiogenesis. MATERIALS AND METHODS: In this pilot study, we assessed the effect of the following drugs on in vitro angiogenesis: atenolol, diltiazem, enalapril, disopyramide, mexiletine, coumadin, cimetidine and omeprazole. RESULTS & CONCLUSION: We observed that, although some of these drugs at massive doses inhibited endothelial proliferation, they did not affect in vitro angiogenesis at human therapeutic ranges.


Assuntos
Inibidores da Angiogênese/farmacologia , Endotélio Vascular/efeitos dos fármacos , Atenolol/farmacologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Cimetidina/farmacologia , Diltiazem/farmacologia , Disopiramida/farmacologia , Avaliação Pré-Clínica de Medicamentos , Enalapril/farmacologia , Endotélio Vascular/citologia , Humanos , Mexiletina/farmacologia , Omeprazol/farmacologia , Projetos Piloto , Varfarina/farmacologia
12.
Clin Chim Acta ; 436: 298-302, 2014 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-24973740

RESUMO

BACKGROUND: The California newborn screening program uses newborns' dried blood spots (DBS) to screen for more than 45 genetic disorders. Deficiency of galactose-1-phosphate uridyl transferase (GALT) is one of the metabolic genetic disorders screened using newborn DBS. During follow-up tests, common mutations of the GALT gene have been identified using whole blood samples. To avoid the stress of drawing an additional blood sample from newborns who are identified as presumptive positive for galactosemia, we developed a method to test common mutations in the GALT gene using blood spots. METHODS: This method involves DNA extraction from DBS, followed by polymerase chain reaction (PCR), and single nucleotide extension (SNE). SNE products were detected by capillary electrophoresis. RESULTS: In a double-blind study, GALT gene common mutations/variants: IVS2-2A>G, p.S135L, p.T138M, p.Q188R, p.L195P, p.Y209C, p.L218L, p.K285N, and p.N314D were detected in seventy-three DBS which had previously been screened and confirmed as positive in the California Newborn Screening Program. Mutations found using blood spots gave 100% concordance with mutations from previously genotyped whole blood samples. CONCLUSIONS: This blood spot method decreases the genomic test turnaround time of GALT screened positive patients and potentially reduces emotional stress on families required to provide an additional blood draw.


Assuntos
Análise Mutacional de DNA/métodos , Teste em Amostras de Sangue Seco , Mutação , UDPglucose-Hexose-1-Fosfato Uridiltransferase/sangue , UDPglucose-Hexose-1-Fosfato Uridiltransferase/genética , Método Duplo-Cego , Técnicas de Genotipagem , Humanos , Recém-Nascido
13.
Cancer Biol Ther ; 6(6): 936-41, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17568184

RESUMO

EG-1 is a gene product that is significantly elevated in human breast cancer tissues. Previously, we have shown that EG-1 overexpression stimulates cellular proliferation both in vitro and in vivo. Here, we ask whether this molecule can be targeted for experimental therapeutic purpose. siRNA lentivirus and polyclonal antibodies were designed to suppress EG-1 expression. These agents were then used in cell culture proliferation assays and breast tumor xenograft models. Serum and urine from breast cancer patients were also analyzed for the presence of EG-1 peptide. We report here for the first time that endogenous EG-1 can be targeted to inhibit breast tumor growth. This inhibition, whether delivered via siRNA lentivirus or polyclonal antibody, resulted in decreased cellular proliferation in culture and smaller xenografts in mice. The effects were shown in both ER (estrogen receptor)-positive human breast cancer MCF-7 cells, as well as in ER-negative MDA-MB-231 cells. Furthermore, we detected soluble EG-1 in serum and urine of breast cancer patients. These observations demonstrate that EG-1 is relevant to human breast cancer, and is a molecular target worthy of translational efforts into effective breast cancer therapy.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Regulação Neoplásica da Expressão Gênica , Neoplasias Mamárias Animais/patologia , Neoplasias Mamárias Animais/terapia , Proteínas/antagonistas & inibidores , Proteínas/fisiologia , Animais , Neoplasias da Mama/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Lentivirus/metabolismo , Neoplasias Mamárias Animais/metabolismo , Complexo Mediador , Camundongos , Camundongos SCID , Transplante de Neoplasias , RNA Interferente Pequeno/metabolismo
14.
Carcinogenesis ; 27(12): 2424-33, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16785249

RESUMO

Epidemiologic data have suggested that green tea may prevent breast cancer. Studies in our laboratory have provided evidence that green tea extract inhibits breast cancer growth by a direct anti-proliferative effect on the tumor cells, as well as by indirect suppressive effects on the tumor-associated endothelial cells. In this study, we asked whether concurrent administration of green tea may add to the anti-tumor effects of standard breast cancer therapy. We observed that green tea increased the inhibitory effect of tamoxifen on the proliferation of the ER (estrogen receptor)-positive MCF-7, ZR75, T47D human breast cancer cells in vitro. This combination regimen was also more potent than either agent alone at increasing cell apoptosis. In animal experiments, mice treated with both green tea and tamoxifen had the smallest MCF-7 xenograft tumor size, and the highest levels of apoptosis in tumor tissue, as compared with either agent administered alone. Moreover, the suppression of angiogenesis in vivo correlated with larger areas of necrosis and lower tumor blood vessel density in treated xenografts. Green tea decreased levels of ER-alpha in tumors both in vitro and in vivo. We also observed that green tea blocked ER-dependent transcription, as well as estradiol-induced phosphorylation and nuclear localization of mitogen-activated protein kinase. To our knowledge, this study is the first to show the interaction of green tea with the ER pathway, as well as provide mechanistic evidence that the combination of green tea and tamoxifen is more potent than either agent alone in suppressing breast cancer growth. These results may lead to future improvements in breast cancer treatment and prevention.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Extratos Vegetais/farmacologia , Tamoxifeno/farmacologia , Animais , Apoptose , Bebidas , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Receptor alfa de Estrogênio/efeitos dos fármacos , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Camundongos , Camundongos Nus , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Extratos Vegetais/uso terapêutico , Tamoxifeno/uso terapêutico , Transcrição Gênica/efeitos dos fármacos , Transplante Heterólogo
15.
Nutr Cancer ; 49(1): 59-65, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15456636

RESUMO

Many laboratory-based studies have shown that soy can suppress breast cancer proliferation. However, given the recent controversy generated by animal experiments that soy may under certain conditions stimulate breast cancer growth, we decided to carry out a pilot clinical trial in order to elucidate any interaction(s) between short-term isoflavone supplement administration and breast cancer growth. After a core-needle biopsy established the diagnosis of breast cancer, 17 patients were administered soy isoflavone tablets for two weeks. This surgically based study provided the unique opportunity to make objective observations based on human breast cancer tissues and blood obtained prior to and after isoflavone supplement treatment in the same patient. Twenty-six historical control cases with similar characteristics to the experimental patients were selected for comparison. We observed that the apoptosis/mitosis ratios in isoflavone-treated cancer specimens were not significantly different from those of control untreated cancer specimens. Furthermore, there appeared to be a statistically nonsignificant trend towards cancer growth inhibition in the isoflavone treatment group, as manifested by higher apoptosis/mitosis ratios compared with those from the control untreated group. Ex vivo/in vitro assays using serum from breast cancer patients prior to and at the conclusion of soy treatment reveal no significant proliferative changes on both breast cancer cells and endothelial cells. We concluded that the effect of soy on breast cancer deserves further studies in larger clinical trials.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/prevenção & controle , Divisão Celular/efeitos dos fármacos , Glycine max/química , Isoflavonas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Neoplasias da Mama/urina , Suplementos Nutricionais , Feminino , Humanos , Pessoa de Meia-Idade , Projetos Piloto
16.
J Nutr ; 132(8): 2307-11, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12163680

RESUMO

Investigators have shown that green tea and its main catechin epigallocatechin-3 gallate (EGCG) may decrease the risk of cancer. Our previous study showed that green tea extract (GTE) as well as its individual catechin components inhibited MDA-MB231 breast cancer cell and human umbilical vein endothelial cell (HUVEC) proliferation. Further, GTE suppressed breast cancer xenograft size and decreased the tumor vessel density in vivo. In the current study, we investigated the effect of GTE on the major angiogenic factor vascular endothelial growth factor (VEGF) in an in vitro experiment. GTE or EGCG (40 mg/L) significantly decreased the levels of the VEGF peptide secreted into conditioned media. This occurred in both HUVEC and human breast cancer cells and the effect was dose dependent. Furthermore, GTE and EGCG decreased the RNA levels of VEGF in MDA-MB231 cells. This inhibition occurred at the transcriptional regulation level and was accompanied by a significant decrease in VEGF promoter activity. We also showed that GTE decreased c-fos and c-jun RNA transcripts, suggesting that activator protein (AP)-1-responsive regions present in the human VEGF promoter may be involved in the inhibitory effect of GTE. Furthermore, GTE suppressed the expression of protein kinase C, another VEGF transcription modulator, in breast cancer cells. Inhibition of VEGF transcription appeared to be one of the molecular mechanism(s) involved in the antiangiogenic effects of green tea, which may contribute to its potential use for breast cancer treatment and/or prevention.


Assuntos
Bebidas , Neoplasias da Mama/metabolismo , Catequina/análogos & derivados , Catequina/farmacologia , Fatores de Crescimento Endotelial/antagonistas & inibidores , Fatores de Crescimento Endotelial/genética , Endotélio Vascular/fisiologia , Linfocinas/antagonistas & inibidores , Linfocinas/genética , Extratos Vegetais/farmacologia , Northern Blotting , Células Cultivadas , Meios de Cultivo Condicionados , Endotélio Vascular/efeitos dos fármacos , Feminino , Humanos , Cinética , Proteína Quinase C/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos , Veias Umbilicais , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
17.
Int J Cancer ; 98(2): 234-40, 2002 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-11857414

RESUMO

In our study, we present experimental evidence suggesting that curcumin exerts multiple different suppressive effects on human breast carcinoma cells in vitro. Our experiments demonstrate that curcumin's antiproliferative effects are estrogen dependent in ER (estrogen receptor)-positive MCF-7 cells, being more pronounced in estrogen-containing media and in the presence of exogenous 17-beta estradiol. Curcumin inhibits the expression of ER downstream genes including pS2 and TGF-beta (transforming growth factor) in ER-positive MCF-7 cells, and this inhibition is also dependent on the presence of estrogen. Curcumin also decreases ERE (estrogen responsive element)-CAT activities induced by 17-beta estradiol. In addition, we demonstrate that curcumin exerts strong anti-invasive effects in vitro that are not estrogen dependent in the ER-negative MDA-MB-231 breast cancer cells. These anti-invasive effects appear to be mediated through the downregulation of MMP-2 (matrix metalloproteinase) and the upregulation of TIMP-1 (tissue inhibitor of metalloproteinase), 2 common effector molecules that have been implicated in regulating tumor cell invasion. Our study also demonstrates that curcumin inhibits the transcript levels of 2 major angiogenesis factors VEGF (vascular endothelial growth factor) and b-FGF (basic fibroblast growth factor) mainly in ER-negative MDA-MB-231 cells.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Carcinoma/metabolismo , Curcumina/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma/genética , Carcinoma/patologia , Divisão Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/metabolismo , Relação Dose-Resposta a Droga , Antagonistas de Estrogênios/farmacologia , Feminino , Humanos , Invasividade Neoplásica , Neovascularização Patológica , Proteínas/genética , Proteínas/metabolismo , RNA Neoplásico/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Elementos de Resposta , Transcrição Gênica , Fator de Crescimento Transformador alfa/genética , Fator de Crescimento Transformador alfa/metabolismo , Fator Trefoil-1 , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor
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