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1.
Lupus ; 22(6): 583-96, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23535532

RESUMO

OBJECTIVE: Systemic lupus erythematosus (SLE) is an autoimmune disease that affects women nine times more often than men. The present study investigates estradiol-dependent control of the calcium-buffering protein, calreticulin, to gain further insight into the molecular basis of abnormal T cell signaling in SLE T cells. METHODS: T cells were purified from blood samples obtained from healthy females and SLE patients. Calreticulin expression was quantified by real-time polymerase chain amplification. Calreticulin and estrogen receptor-α were co-precipitated and analyzed by Western blotting to determine if the proteins associate in T cells. RESULTS: Calreticulin expression increased (p = 0.034) in activated control T cells, while estradiol decreased (p = 0.044) calreticulin in resting T cells. Calreticulin expression decreased in activated SLE T cell samples and increased in approximately 50% of resting T cell samples. Plasma estradiol was similar (p > 0.05) among SLE patients and control volunteers. Estrogen receptor-α and calreticulin co-precipitated from nuclear and cytoplasmic T cell compartments. CONCLUSIONS: The results indicate that estradiol tightly regulates calreticulin expression in normal human T cells, and the dynamics are different between activated and resting T cells. The absence of this tight regulation in SLE T cells could contribute to abnormal T cell function.


Assuntos
Calreticulina/metabolismo , Estradiol/metabolismo , Lúpus Eritematoso Sistêmico/fisiopatologia , Linfócitos T/patologia , Adulto , Western Blotting , Estudos de Casos e Controles , Receptor alfa de Estrogênio/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Lúpus Eritematoso Sistêmico/epidemiologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Fatores Sexuais , Transdução de Sinais , Linfócitos T/metabolismo
2.
Lupus ; 17(6): 548-54, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18539708

RESUMO

Systemic lupus erythematosus (SLE) is an autoimmune disease that occurs primarily in women of reproductive age. The disease is characterized by exaggerated T-cell activity and abnormal T-cell signalling. The mitogen-activated protein kinase (MAPK) pathway is involved in the maintenance of T-cell tolerance that fails in patients with SLE. Oestrogen is a female sex hormone that binds to nuclear receptors and alters the rate of gene transcription. Oestrogen can also act through the plasma membrane and rapidly stimulate second messengers including calcium flux and kinase activation. In this study, we investigated whether oestrogen influences the activation of MAPK signalling through the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) in activated SLE T cells. SLE and control T cells were cultured in serum-free medium without and with oestradiol (10(-7) M) for 18 h. The T cells were activated with phorbol 12 myristate 13-acetate and ionomycin for various time points (0-60 min), and the amount of phosphorylated ERK1/2 was measured by immunoblotting. There were no differences in ERK1/2 phosphorylation between SLE and control T cells at 5 and 15 min after the activation stimulus. However, comparison between the amount of phosphorylated ERK1/2 in SLE T cells from the same patients cultured without and with oestradiol showed a significant oestrogen-dependent suppression (P=0.48) of ERK1/2 in patients with inactive/mild systemic lupus erythematosus disease activity index (SLEDAI) (0-2) compared with patients with moderate (4-6) or active (8-12) SLEDAI scores. These results suggest that the suppression of MAPK through ERK1/2 phosphorylation is sensitive to oestradiol in patients with inactive or mild disease, but the sensitivity is not maintained when disease activity increases. Furthermore, studies are now necessary to understand the mechanisms by which oestrogen influences MAPK activation in SLE T cells.


Assuntos
Estrogênios/metabolismo , Lúpus Eritematoso Sistêmico/metabolismo , Sistema de Sinalização das MAP Quinases , Adulto , Células Cultivadas , Ativação Enzimática , Feminino , Humanos , Lúpus Eritematoso Sistêmico/fisiopatologia , Ativação Linfocitária , Pessoa de Meia-Idade , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia
3.
Histopathology ; 48(3): 258-67, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16430472

RESUMO

AIMS: Immunohistochemistry (IHC) and fluorescence in-situ hybridization (FISH) are both commonly used assays for evaluation of HER-2/neu status in breast cancer. However, there is still no consensus on which method is most predictive of patient response to Herceptin. Recently, the automated cellular imaging system (ACIS) has been shown to improve the accuracy and reproducibility in scoring IHC. Our aim was to compare the results of HER-2/neu expression and gene amplification in the same patients by IHC using the ACIS system and by FISH. METHODS AND RESULTS: Two hundred and forty-seven breast cancer cases were studied. The concordance rate between IHC-ACIS (> or = 2.2) and FISH (> or = 2.0) was 94%. Fifteen patients were discordant; three had borderline FISH values and three had borderline IHC values. The other nine discordant cases consisted of five IHC-ACIS+, FISH- and six IHC-ACIS-, FISH+. HER-2/neu overexpression was more common in tumours that were high-grade, aneuploid, progesterone receptor and bcl-2 negative, with MIB-1 > 10%. CONCLUSION: HER-2/neu assessment by the ACIS is reliable, rapid and inexpensive, and correlates highly with results obtained by FISH.


Assuntos
Neoplasias da Mama/química , Processamento de Imagem Assistida por Computador/métodos , Imuno-Histoquímica/métodos , Hibridização in Situ Fluorescente , Receptor ErbB-2/análise , Receptor ErbB-2/genética , Adenocarcinoma/química , Adenocarcinoma/genética , Adenocarcinoma Mucinoso/química , Adenocarcinoma Mucinoso/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Neoplasias da Mama/genética , Carcinoma Ductal de Mama/química , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/química , Carcinoma Lobular/genética , Carcinoma Medular/química , Carcinoma Medular/genética , Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Receptor ErbB-2/biossíntese
4.
Lupus ; 15(12): 852-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17211990

RESUMO

Previous studies in our laboratory showed a dose-dependent and hormone-specific increase in CD154 expression in T cells from females with systemic lupus erythematosus (SLE). This present study investigates if the estrogen-dependent increase in CD154 expression is due to stabilization of the messenger RNA. T cells from female SLE patients and controls were cultured for 18 h in serum-free medium without and with estradiol 17-beta (10(-7) M). T cells were either unstimulated (resting) or were activated by further culture on anti-CD3 coated plates. Actinomycin D (25 microg/mL) was added to parallel cultures to inhibit new messenger RNA synthesis. CD154 messenger RNA stability was assessed by reverse-transcription polymerase chain amplification. Resting SLE (n = 10, P = 0.88) and normal (n = 7, P = 0.65) T cells showed no significant differences in message stability in response to estradiol. CD154 messenger RNA was also not significantly stabilized in activated SLE (n = 10, P = 0.15) or activated normal (n = 6, P = 0.077) T cells in response to estradiol. These findings indicate that the estrogen-dependent increase in CD154 in SLE T cells is not due to stability of the mRNA. These data are consistent with the postulate that estradiol stimulates CD154 transcription in SLE T cells.


Assuntos
Ligante de CD40/genética , Estradiol/farmacologia , Lúpus Eritematoso Sistêmico/fisiopatologia , Estabilidade de RNA/efeitos dos fármacos , Linfócitos T/fisiologia , Adulto , Células Cultivadas , Estradiol/fisiologia , Feminino , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Ativação Linfocitária/imunologia , Pessoa de Meia-Idade , Estabilidade de RNA/imunologia , RNA Mensageiro/metabolismo , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/imunologia
5.
Endocr Relat Cancer ; 12(2): 185-213, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15947097

RESUMO

Breast tissue and duct fluid provide a rich source of biomarkers to both aid in the assessment of short-term risk of developing breast cancer and predict and assess responses to prevention interventions. There are three methods currently being utilized to sample breast tissue in asymptomatic women for risk assessment: nipple-aspirate fluid (NAF), random periareolar fine-needle aspiration (RPFNA) and ductal lavage. Prospective single-institution trials have shown that the presence of atypical cells in NAF fluid or RPFNA specimens is associated with an increased risk of breast cancer. Furthermore, RPFNA-detected atypia has been observed to further stratify risk based on the commonly used Gail risk-assessment model. A prospective trial evaluating risk prediction on the basis of atypical cells in ductal-lavage fluid is ongoing. The ability of other established non-genetic biomarkers (mammographic breast density; serum levels of bioavailable estradiol, testosterone, insulin-like growth factor-1 and its insulin like growth factor binding protein-3) to stratify risk based on the Gail model is as yet incompletely defined. Modulation of breast intra-epithelial neoplasia (i.e. hyperplasia with or without atypia) with or without associated breast-tissue molecular markers, such as proliferation, is currently being used to evaluate response in Phase II chemoprevention trials. RPFNA has been the method most frequently used for Phase II studies of 6-12 months duration. However, ductal lavage, RPFNA and random and directed core needle biopsies are all being utilized in ongoing multi-institutional Phase II studies. The strengths and weaknesses of each method are reviewed.


Assuntos
Biomarcadores Tumorais/análise , Biópsia/métodos , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/prevenção & controle , Mama/patologia , Ensaios Clínicos como Assunto , Feminino , Humanos , Medição de Risco
7.
Breast J ; 7(5): 311-20, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11906441

RESUMO

The demonstration by the National Surgical Adjuvant Breast Project (NSABP) that 5 years of tamoxifen therapy is associated with an approximate 50% reduction in breast cancer incidence in high-risk women was a milestone in breast cancer prevention. Because tamoxifen is associated with increased risk of side-effects such as hot flashes, menstrual abnormalities, uterine cancer, and thromboembolic phenomena, its use will not be advisable or acceptable for all high-risk women. Women over 50 years of age appear to be at highest risk for serious adverse events, such as uterine cancer and thromboembolic phenomena. Individuals in whom tamoxifen-associated breast cancer risk reduction appears to outweigh risk of serious side-effects include women with prior in situ or estrogen receptor (ER)-positive invasive cancer, atypical hyperplasia, and/or women ages 35-49 with a calculated Gail 5-year risk of > or =1.7%, hysterectomized women aged 50 and older with a 5-year Gail risk of > or =2.5%, and nonhysterectomized women aged 50 and older with a 5-year Gail risk of >5.0%. It is not yet clear whether tamoxifen can reduce breast cancer incidence in women with BRCA1 and BRCA2 mutations, although preliminary evidence favors benefit for at least those with a BRCA2 mutation. Raloxifene is a selective ER modulator with less uterine estrogen agonist activity than tamoxifen, and it is hoped that it will result in fewer uterine cancers but will be equally efficacious in reducing the risk of breast cancer. The NSABP is currently conducting a randomized study of tamoxifen versus raloxifene in high-risk postmenopausal women. Approximately one third of invasive cancers are ER negative. Tamoxifen does not reduce the incidence of ER-negative cancers, nor does it appear to be effective in preventing the appearance of one third of ER-positive cancers. Priorities in prevention research are to develop (a) biomarkers to refine short-term risk assessments based on epidemiologic models, (b) biomarkers predictive of response to specific classes of preventive agents, (c) drugs with fewer side-effects and/or effective in ER-negative or ER-positive tamoxifen-resistant precancerous disease, and (d) efficient clinical trial models to assess new agent efficacy. Breast intraepithelial neoplasia (IEN) may be sampled by minimally invasive techniques and is an attractive short-term risk biomarker. Molecular abnormalities observed in IEN may be used to select potential agents for testing/therapy, and modulation of these abnormalities may be used in phase I trials to select appropriate doses and in phase II trials to assess response. Breast density volume and certain serum markers such as insulin-like growth factor-1 are also being studied as potential risk and response biomarkers. Reversal or prevention of advanced IEN as well as modulation of other risk biomarkers in randomized phase II and phase III trials is being evaluated as a means of more efficiently evaluating prevention drugs in the future. A number of agents are being developed that target molecular abnormalities in IEN, have fewer or different side effects than tamoxifen, and may be effective in ER-negative or tamoxifen-resistant disease.


Assuntos
Neoplasias da Mama/prevenção & controle , Carcinoma in Situ/prevenção & controle , Ensaios Clínicos como Assunto/tendências , Recidiva Local de Neoplasia/prevenção & controle , Feminino , Humanos , Cloridrato de Raloxifeno/uso terapêutico , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Tamoxifeno/uso terapêutico
8.
Ann N Y Acad Sci ; 952: 44-59, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11795443

RESUMO

Although tamoxifen appears to markedly reduce breast cancer risk in women with a prior diagnosis of atypical hyperplasia or in situ carcinoma, it is not clear what other groups of women receive substantial benefit. Major breast chemoprevention priorities are to (1) develop new agents that (a) have fewer side effects, (b) are effective in ER--as well as tamoxifen-resistant precancerous tissue, and (c) are compatible with hormone therapy; and (2) develop efficient clinical strategies including prognostic and predictive morphologic and molecular biomarkers. Breast tissue may be repeatedly sampled for evidence of intraepithelial neoplasia by fine needle aspiration, ductal lavage, or needle biopsy to select candidates at highest short-term risk as well as to monitor response in small proof of principle studies prior to a large cancer incidence trial. Molecular marker expression may also be used to select a cohort most likely to respond to a particular agent. A large number of new agents are attractive as potential prevention agents and some are already in clinical prevention testing. Compounds which should be effective in ER + precancerous tissue but may have a better side-effect profile include new selective estrogen receptor modulators which lack uterine estrogen agonist activity, isoflavones, aromatase inactivators/inhibitors for postmenopausal women, and gonadotropin-releasing hormone regimens for premenopausal women. Retinoids, rexinoids, and deltanoids may be efficacious in ER+ tissue resistant to tamoxifen. Agents which should theoretically have activity in ER- or ER+ precancerous tissue include polyamine synthesis inhibitors, tyrosine kinase inhibitors, combined demethylating agents and histone deacetylase inhibitors, as well as metalloprotease and angiogenesis inhibitors. Sample Phase I and Phase II clinical trial designs are reviewed using modulation of molecular markers and breast intraepithelial neoplasia as the major endpoints.


Assuntos
Anticarcinógenos/uso terapêutico , Neoplasias da Mama/prevenção & controle , Aneuploidia , Inibidores da Angiogênese/uso terapêutico , Apoptose/efeitos dos fármacos , Inibidores da Aromatase , Neoplasias da Mama/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma in Situ/tratamento farmacológico , Carcinoma in Situ/metabolismo , Carcinoma in Situ/patologia , Ensaios Clínicos Fase II como Assunto , Inibidores de Ciclo-Oxigenase/uso terapêutico , Progressão da Doença , Eflornitina/uso terapêutico , Determinação de Ponto Final , Inibidores Enzimáticos/uso terapêutico , Estrogênios , Feminino , Fenretinida/uso terapêutico , Hormônio Liberador de Gonadotropina/agonistas , Humanos , Hiperplasia , Isoflavonas/uso terapêutico , Proteínas de Neoplasias/análise , Neoplasias Hormônio-Dependentes/prevenção & controle , Fenótipo , Piperidinas/uso terapêutico , Poliaminas/antagonistas & inibidores , Lesões Pré-Cancerosas/tratamento farmacológico , Proteínas Tirosina Quinases/antagonistas & inibidores , Receptores de Estrogênio/análise , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Tamoxifeno/efeitos adversos , Tamoxifeno/uso terapêutico , Tiofenos/uso terapêutico , Neoplasias Uterinas/induzido quimicamente
9.
J Natl Cancer Inst ; 92(15): 1217-27, 2000 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-10922407

RESUMO

BACKGROUND: : Biomarkers are needed to refine short-term breast cancer risk estimates from epidemiologic models and to measure response to prevention interventions. The purpose of our study was to determine whether the cytologic appearance of epithelial cells obtained from breast random periareolar fine-needle aspirates or molecular marker expression in these cells was associated with later breast cancer development. METHODS: : Four hundred eighty women who were eligible on the basis of a family history of breast cancer, prior precancerous biopsy, and/or prior invasive cancer were enrolled in a single-institution, prospective trial. Their risk of breast cancer according to the Gail model was calculated, and random periareolar fine-needle aspiration was performed at study entry. Cells were characterized morphologically and analyzed for DNA aneuploidy by image analysis and for the expression of epidermal growth factor receptor, estrogen receptor, p53 protein, and HER2/NEU protein by immunocytochemistry. All statistical tests are two-sided. RESULTS: : At a median follow-up time of 45 months after initial aspiration, 20 women have developed breast cancer (invasive disease in 13 and ductal carcinoma in situ in seven). With the use of multiple logistic regression and Cox proportional hazards analysis, subsequent cancer was predicted by evidence of hyperplasia with atypia in the initial fine-needle aspirate and a 10-year Gail projected probability of developing breast cancer. Although expression of epidermal growth factor receptor, estrogen receptor, p53, and HER2/NEU was statistically significantly associated with hyperplasia with atypia, it did not predict the development of breast cancer in multivariable analysis. CONCLUSION: : Cytomorphology from breast random periareolar fine-needle aspirates can be used with the Gail risk model to identify a cohort of women at very high short-term risk for developing breast cancer. We recommend that cytomorphology be studied for use as a potential surrogate end point in prevention trials.


Assuntos
Biomarcadores Tumorais/análise , Biópsia por Agulha/métodos , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/prevenção & controle , Mama/patologia , Programas de Rastreamento/métodos , Adulto , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Transformação Celular Neoplásica/química , Transformação Celular Neoplásica/patologia , Feminino , Humanos , Hiperplasia/patologia , Modelos Logísticos , Pessoa de Meia-Idade , Modelos Biológicos , Modelos Estatísticos , Mamilos/química , Mamilos/patologia , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Risco , Fatores de Tempo
10.
Eur J Cancer ; 36(10): 1209-14, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10882858

RESUMO

It is unknown what proportion of women at high risk for breast cancer, entering phase II chemoprevention trials, have BRCA1/2 alterations, and whether their initial biomarker patterns or response to preventive interventions will differ between carriers and non-carriers. As part of a 6-month phase II chemoprevention trial of diflouromethlyornithine (DFMO), high-risk subjects (family history, prior precancerous breast disease or prior breast cancer), who had random peri-areolar fine needle evidence of epithelial hyperplasia with or without atypia, were offered genetic counselling and testing at the completion of their study participation. 97% of the 119 women eligible for testing underwent BRCA1/2 gene sequencing, 3 declined. 26 (22%) of the 116 women had an alteration in BRCA1/2. Known deleterious mutations were present in 3 (3%), uncertain significance mutations in 19 (16%), and probable polymorphisms in 6 (5%). There does not appear to be a difference in initial biomarker distribution between participants with and without germ line alterations.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/genética , Eflornitina/uso terapêutico , Genes BRCA1/genética , Mutação em Linhagem Germinativa/genética , Proteínas de Neoplasias/genética , Fatores de Transcrição/genética , Adulto , Proteína BRCA2 , Neoplasias da Mama/prevenção & controle , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Linhagem , Fatores de Risco
11.
J Cell Biochem Suppl ; 34: 7-12, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10762008

RESUMO

Selection of surrogate endpoint biomarkers (SEBs) and appropriate study design are two of the main challenges in evaluating potential chemopreventive agents. In a prospective random fine-needle aspiration (FNA) study of women at high risk of development of breast cancer, we previously demonstrated that cytologic evidence of epithelial hyperplasia with or without atypia, as well as abnormalities of several cellular biomarkers (DNA ploidy; immunocytochemical expression of p53, EGFR, ER, and/or Her-2/neu), were more prevalent in high-risk women than in low-risk controls. We also demonstrated that the subsequent development of breast cancer was best predicted by an initial presentation of hyperplasia with atypia, as well as by multiple biomarker abnormalities. These findings indicate that FNA cytology and biomarkers can be used to identify women who are appropriate subjects for chemoprevention trials, and can then be used as surrogate endpoint biomarkers to monitor efficacy of potential agents. An example of this use in an ongoing single-agent phase II trial is provided. Several options for study design of possible multi-agent breast cancer chemoprevention trials are discussed, depending upon the existing preclinical and clinical data, the questions being asked, and the number of eligible subjects available.


Assuntos
Biópsia por Agulha/métodos , Neoplasias da Mama/prevenção & controle , Mama/patologia , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/análise , Mama/metabolismo , Neoplasias da Mama/metabolismo , Protocolos Clínicos , Ensaios Clínicos como Assunto , Eflornitina/uso terapêutico , Receptores ErbB/metabolismo , Feminino , Humanos , Hiperplasia , Placebos , Proteína Supressora de Tumor p53/metabolismo
12.
Endocrinology ; 141(2): 637-48, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10650945

RESUMO

Understanding of cell cycle regulation in hormonally responsive cells lags behind studies in other systems because few models have been available to identify the role of steroid hormones and their receptors in this process. This study investigates progesterone-dependent effects on the progression of normal uterine stromal cells through early G1 phase of the cell cycle. Quiescent rat uterine stromal cells were stimulated to reenter the cell cycle by adding serum-free medium containing medroxyprogesterone acetate (MPA) and basic fibroblast growth factor (FGF). [3H]thymidine incorporation increased significantly (P = 0.025) in cells stimulated with both FGF alone and MPA plus FGF compared with the control cells. Moreover, cells stimulated with MPA plus FGF incorporated significantly more (P = 0.01) [3H]thymidine than cells treated with FGF alone, suggesting requisite interactions between progesterone and FGF for stromal cell entry into S phase. Flow cytometric analysis of stimulated stromal cells showed FGF alone and MPA plus FGF increased significantly (P = 0.002) the percentage of cells in S phase at 12 h. Incorporation of bromodeoxyuridine into stromal cell nuclei indicated that FGF alone and MPA plus FGF increased the percentage of cells entering S phase at 18 and 24 h compared with the control cells. In addition, MPA plus FGF increased significantly (P = 0.001) the number of cells entering S phase at 24 h compared with FGF alone and sustained S phase entry compared with FGF alone, MPA alone, or the control cells. Stromal cells inhibited from G1 reentry by inhibition of mitosis showed accelerated entry into S phase in response to MPA plus FGF compared with FGF alone. Cyclin D1 messenger RNA increased in stromal cells treated with MPA plus FGF at 9, 12, and 15 h. Addition of RU 486 to cells stimulated with MPA plus FGF for 9 h reduced cyclin D1 messenger RNA accumulation by 40%. Western blot analysis of cyclin D1 immunoprecipitates indicated complex formation with both cyclin-dependent kinase 4 (Cdk4) and cyclin dependent kinase 6 (Cdk6). Cyclin D1-Cdk complexes and kinase activity correlated temporally with increased cyclin D1 expression in cells cultured with MPA plus FGF. Taken together, these results show that progesterone-FGF interactions increase cyclin D1 expression, correlating with accelerated stromal cell entry into S phase compared with cells treated with FGF alone. Moreover, progesterone plus FGF sustains the timing of stimulation for transit of uterine stromal cells through G1 into S phase compared with FGF alone.


Assuntos
Ciclo Celular/fisiologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Acetato de Medroxiprogesterona/farmacologia , Progesterona/fisiologia , Útero/citologia , Animais , Ciclo Celular/efeitos dos fármacos , Células Cultivadas , Ciclina D1/genética , DNA/biossíntese , Feminino , Citometria de Fluxo , Fase G1 , Regulação da Expressão Gênica/efeitos dos fármacos , Cinética , Ovariectomia , Progesterona/farmacologia , Ratos , Ratos Sprague-Dawley , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Células Estromais/fisiologia , Timidina/metabolismo , Transcrição Gênica/efeitos dos fármacos
13.
Cancer ; 86(4): 664-71, 1999 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10440695

RESUMO

BACKGROUND: A multiple sampling study was performed on 124 specimens of renal cell carcinomas to analyze the consistency and reliability of DNA measurements. The authors investigated intratumoral DNA heterogeneity and its role as a adverse prognostic factor for disease progression. METHODS: DNA content was analyzed by flow cytometry on three different samples of the same tumor. The Cronbach alpha coefficient was used to assess the reliability and a Cox proportional hazards model was used to test the effect of DNA ploidy heterogeneity on time of disease progression. RESULTS: The agreement among the DNA ploidy samples was high. The number of aneuploid findings increased significantly with the number of samples analyzed. The presence of non-diploid cell populations was a significant adverse predictive value for disease progression. However, the authors were unable to demonstrate that intratumoral heterogeneity DNA content had any influence on the biological behavior of the tumor. CONCLUSIONS: Determination of DNA ploidy based on single samples may be inaccurate. Spatial variation in DNA ploidy is a feature of renal cell carcinoma; however, its biologic significance remains to be demonstrated.


Assuntos
Carcinoma de Células Renais/genética , DNA de Neoplasias/análise , Variação Genética , Neoplasias Renais/genética , Adulto , Idoso , Carcinoma de Células Renais/patologia , DNA de Neoplasias/genética , Progressão da Doença , Feminino , Humanos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Ploidias , Valor Preditivo dos Testes , Prognóstico
14.
Toxicol Lett ; 104(3): 183-7, 1999 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-10079052

RESUMO

Metallothionein (MT) has been proposed to play a protective role against the toxic effects of free radicals and electrophiles, such as those produced by gamma-radiation. Therefore, this study was designed to determine whether MT-transgenic mice, which carry 56 copies of the MT-I transgene and have higher tissue MT concentrations, are resistant to the toxic effects of gamma-radiation. Mice were exposed to 137cesium radiation, and survival was followed for 30 days. At all doses (7-12 Gy) examined, no difference in the survival was observed between control and MT-transgenic mice. The average survival times between control and MT-transgenic mice were also similar. Leukocytes were decreased 78 +/- 7% and 75 +/- 11% in control and MT-transgenic mice respectively 5 days after radiation. Furthermore, MT-transgenic mice were also equally susceptible as control mice to the lethal toxic effects produced by cyclophosphamide (1.75 mmol/kg, i.p.). In summary, MT-I transgenic mice are not protected against the toxic effects produced by gamma-radiation or cyclophosphamide.


Assuntos
Raios gama , Metalotioneína/genética , Tolerância a Radiação/genética , Animais , Ciclofosfamida/toxicidade , Relação Dose-Resposta à Radiação , Contagem de Leucócitos/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutagênicos/toxicidade
16.
Brain Res Dev Brain Res ; 107(1): 49-55, 1998 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-9602055

RESUMO

To investigate the effect of a delay in ovulation on postnatal growth and development in resultant rat offspring, a 1-day ovulatory delay was induced by sodium pentobarbital, animals mated, and the offspring monitored. There were no differences between control and 1-day delayed offspring in the number of live or dead births, number of males or females, nor in the ratio of sexes. Delayed pups had a slightly lower birth weight, but then recovered to weigh more than controls by day 12. In the first two weeks post-parturition, delayed pups displayed an earlier ability to reorient themselves in a negative geotaxis test, but no differences by the righting reflex and reflex suspension tests. At postnatal day (pnd) 28, delayed pups exhibited decreased activity in a continuous corridor test, but no alterations in gait. At this time, the brains of delayed animals revealed thickening of cortical layers V plus VI. There were significant correlations between various developmental endpoints (body weight, negative geotaxis, continuous corridor activity, and gait) and the cortical layer thicknesses. The results indicate that ovulatory delay produces changes in brain cortical thickness, with correlative changes in growth and behavior. Although the mechanisms by which ovulatory delay alters postnatal development and brain structure are unknown, ovulatory delay may alter the uterine environment during early pregnancy.


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Animais Recém-Nascidos/psicologia , Comportamento Animal/fisiologia , Encéfalo/anatomia & histologia , Ovulação/fisiologia , Animais , Animais Recém-Nascidos/anatomia & histologia , Encéfalo/crescimento & desenvolvimento , Córtex Cerebral/anatomia & histologia , Feminino , Marcha/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley , Análise de Regressão , Fatores de Tempo , Aumento de Peso/fisiologia
17.
Int J Radiat Biol ; 73(4): 423-34, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9587081

RESUMO

Irradiation of the mammalian foetus produces a broad spectrum of congenital abnormalities, growth retardations, developmental delays, and functional deficits, depending upon the dose and the specific gestational phase of irradiation. The developing brain is particularly susceptible to production of deleterious effects, with decreased brain size, behavioural alterations, and mental retardation having been documented. Supplementing the limited human data, rodent models have been extensively used to investigate the specific processes by which relatively low doses, with correspondingly minor cellular damage to the developing neocortex, can produce dramatic postnatal consequences in brain structure and function. The effects of a variety of physical (dose, linear energy transfer, dose rate, fractionation) and biological (species, strain, gestational age, time course post-irradiation) parameters have been examined in an attempt to provide much needed information on such critical aspects as dose response, threshold doses for effect, and extrapolation to human risk estimates. Various acute cellular responses (e.g. appearance of pyknotic cells and macrophages) observed in the developing neocortex 0-24 h after in utero irradiation can be associated with postnatal effects. Moreover, it is possible to correlate thinning of specific layers of the cerebral cortex with specific behavioural aberrations, allowing prediction of brain structural changes from functional alterations, and vice versa. Thus, it is possible to speculate as to the mechanisms and targets for extremely sensitive, radiation-induced cellular damage in the developing foetal brain, that will interfere with the orderly and precisely programmed development of the mammalian brain, leading finally to postnatal expression as delays in growth and development, perturbations in behaviour, and alterations in brain structure.


Assuntos
Encéfalo/efeitos da radiação , Desenvolvimento Embrionário e Fetal/efeitos da radiação , Feto/efeitos da radiação , Animais , Apoptose/efeitos da radiação , Encéfalo/citologia , Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Diferenciação Celular/efeitos da radiação , Divisão Celular/efeitos da radiação , Movimento Celular/efeitos da radiação , Humanos , Camundongos , Liberação Nociva de Radioativos , Radiografia/efeitos adversos , Ratos , Fatores de Risco
18.
Hematol Oncol Clin North Am ; 12(5): 993-1017, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9888018

RESUMO

Several models are being explored for use in the phase I and phase II evaluation of breast cancer chemoprevention agents. The short-term DCIS/small invasive cancer model is probably best used in late phase I trials in conjunction with agents likely to have activity in the progression phase of neoplastic development in addition to activity in earlier phases. The core biopsy or FNA hyperplasia models may be best used with drugs that are likely to have activity primarily in the promotion phase of neoplastic development and that are suitable for longer duration trials lasting several months to years. Morphology currently is the key surrogate endpoint biomarker for assessing efficacy in phase II trials. Other biomarkers that may undergo modulation will have to be validated, in that modulation will have to be shown to be directly related to decreased cancer risk in subsequent phase III trials. Only then can they be considered as validated surrogate endpoint biomarkers and used as stand-alone efficacy markers in phase II trials. Despite accrual challenges and technologic hurdles, interest in phase I and phase II chemoprevention trials is high.


Assuntos
Neoplasias da Mama/prevenção & controle , Quimioprevenção , Ensaios Clínicos Fase I como Assunto/métodos , Ensaios Clínicos Fase II como Assunto/métodos , Feminino , Humanos
19.
Cancer Chemother Pharmacol ; 39(3): 273-7, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-8996532

RESUMO

PURPOSE: This study was performed to investigate the effects of morphine on the disposition of 5-fluorouracil (5-FU). METHODS: Mice were injected subcutaneously (s.c.) with saline or morphine, 20 mg/kg. 5-FU was administered intravenously (i.v.) 30 min later as a single bolus or by constant infusion. Blood samples were obtained by orbital sinus puncture. Urine samples were obtained from the bladder after ligation of the external urethra. 5-FU concentrations in plasma and urine were determined by HPLC. RESULTS: Morphine markedly elevated plasma levels of 5-FU given at doses of 100 to 860 mg/kg. The plasma clearance rate of a bolus dose of 100 mg/kg 5-FU was significantly reduced from 54 to 28 ml/min per kg and the elimination half-life was increased from 6.9 to 12.2 min by prior administration of morphine. When 5-FU was infused at 0.5 mg/kg per min, morphine reduced its plasma clearance rate from 145 to 94 ml/min per kg. Mice made tolerant by prior morphine administration required higher doses of this opiate to raise 5-FU levels as well as to cause analgesia. The effects of morphine on 5-FU disposition were antagonized by naltrexone. Excretion of 5-FU in urine was not affected by morphine treatment. CONCLUSIONS: The plasma clearance rate of 5-FU in mice is significantly reduced by concomitant use of morphine. This effect of morphine is due to reduced hepatic elimination of 5-FU rather than to a decrease in its renal excretion.


Assuntos
Analgésicos Opioides/farmacologia , Antimetabólitos Antineoplásicos/metabolismo , Fluoruracila/metabolismo , Fígado/metabolismo , Morfina/farmacologia , Analgésicos Opioides/antagonistas & inibidores , Animais , Antimetabólitos Antineoplásicos/farmacocinética , Interações Medicamentosas , Feminino , Fluoruracila/farmacocinética , Masculino , Camundongos , Camundongos Endogâmicos ICR , Morfina/antagonistas & inibidores , Naltrexona/farmacologia
20.
J Cell Biochem Suppl ; 28-29: 101-10, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9589354

RESUMO

In a prospective pilot study, we performed breast fine needle aspirations (FNAs) on 224 high-risk and 30 low-risk women and analyzed these aspirates for cytologic changes and biomarker abnormalities of aneuploidy and overexpressed estrogen receptor (ER), epidermal growth factor receptor (EGFR), p53 and HER-2/neu. High-risk women had a first-degree relative with breast cancer (74%), prior biopsy indicating premalignant breast disease (25%), a history of breast cancer (13%), or some multiple of these risk factors (12%). Median ages of the high- and low-risk groups were 44 and 42, respectively. Seventy percent of high-risk and 17% of low-risk women had cytologic evidence of hyperplasia with or without atypia (P < .0001). Aneuploidy and overexpression of EGFR and p53 occurred in 27, 37, and 29% of high-risk subjects but only 0, 3, and 3% of low-risk subjects (P < .0023). Overexpression of ER and HER-2/neu occurred in 7 and 20% of high-risk women but in none of the low-risk subjects. Biomarker abnormalities were more frequent with increasing cytologic abnormality. Restricting the analysis to those 3 biomarkers most frequently overexpressed in the high-risk group (ploidy, EGFR, p53), 13% of high-risk women with normal cytology, 19% of high-risk women with epithelial hyperplasia, and 49% of high-risk women with hyperplasia with atypia had abnormalities of 2 or more of these 3 biomarkers (P = .00004). At a median follow-up of 32 months, four women have been diagnosed with invasive cancer and two with ductal carcinoma in situ (DCIS). Later detection of these neoplastic conditions was associated (P < or = .016) by univariate analysis with prior FNA evidence of hyperplasia with atypia; overexpression of p53 and EGFR; the modified Gail risk of breast cancer development at 10 years; and multiple biomarker abnormalities. By multivariate analysis, later detection of cancer was primarily predicted by the number of biomarker abnormalities in the 3-test battery (P = .0005) and secondarily by the Gail risk at 10 years (P = .0049). In turn, hyperplasia with atypia was associated with multiple biomarker abnormalities, particularly p53 and EGFR overexpression. Thus, hyperplasia with atypia and cytologic markers in breast FNAs have promise as risk predictors and as surrogate endpoint biomarkers for breast cancer chemoprevention trials.


Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Adulto , Idoso , Biomarcadores Tumorais , Biópsia por Agulha , Neoplasias da Mama/prevenção & controle , Quimioprevenção , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Medição de Risco
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