Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Peptídeo 1 Semelhante ao Glucagon/análise , Hipoglicemia/etiologia , Feocromocitoma/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/complicações , Glicemia , Humanos , Hipoglicemia/diagnóstico , Insulina/sangue , Radioisótopos do Iodo , Imageamento por Ressonância Magnética , Feocromocitoma/complicações , CintilografiaRESUMO
Aminopeptidase N, or CD13, is a receptor for serologically related coronaviruses of humans, pigs, and cats. A mouse line transgenic for the receptor of human coronavirus-229E (HCoV-229E) was created using human APN (hAPN) cDNA driven by a hAPN promoter. hAPN-transgenic mice expressed hAPN mRNA in the kidney, small intestine, liver, and lung. hAPN protein was specifically expressed on epithelial cells of the proximal convoluted renal tubules, bronchi, alveolar sacs, and intestinal villi. The hAPN expression pattern within transgenic mouse tissues matched that of mouse APN and was similar in mice heterozygous or homozygous for the transgene. Primary embryonic cells and bone marrow dendritic cells derived from hAPN-transgenic mice also expressed hAPN protein. Although hAPN-transgenic mice were resistant to HCoV-229E in vivo, primary embryonic cells and bone marrow dendritic cells were infected in vitro. hAPN-transgenic mice are valuable as a source of primary mouse cells expressing hAPN. This hAPN-transgenic line will also be used for crossbreeding experiments with other knockout, immune deficient, or transgenic mice to identify factors, in addition to hAPN, that are required for HCoV-229E infection.
Assuntos
Antígenos CD13/genética , Antígenos CD13/metabolismo , Coronavirus Humano 229E/fisiologia , Animais , Brônquios/citologia , Células Cultivadas , Células Dendríticas/metabolismo , Células Dendríticas/virologia , Embrião de Mamíferos/citologia , Embrião de Mamíferos/virologia , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Feminino , Heterozigoto , Homozigoto , Humanos , Mucosa Intestinal/metabolismo , Rim/metabolismo , Camundongos , Camundongos Transgênicos , Especificidade de Órgãos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transgenes/genéticaRESUMO
OBJECTIVE: Alcohol is associated with acute hypoglycemia in patients with type 1 diabetes. After drinking alcohol in the evening, delayed hypoglycemia has also been described, although its cause is unknown. We performed a controlled study to investigate this phenomenon. RESEARCH DESIGN AND METHODS: We admitted six men with type 1 diabetes (aged 19-51 years, HbA(1c) 7.0-10.3%) on two occasions, from 5:00 P.M. to 12:00 noon the following day. They received regular insulin injections before standardized meals, at 6:00 P.M. and 8:00 A.M., and a basal insulin infusion (0.15 mU x kg(-1) x min(-1)) from 11:00 P.M. They drank either dry white wine (0.75 g/kg alcohol) or mineral water at 9:00 P.M. over 90 min. Blood glucose, alcohol, insulin, cortisol, growth hormone, and glucagon levels were measured. RESULTS: Blood ethanol reached a mean (SEM) peak of 19.1 (1.2) mmol/l and was undetectable by 8:00 A.M. There were no significant differences in evening or overnight blood glucose levels between the studies. In the morning, fasting and postprandial blood glucose levels were significantly lower after consumption of wine (postprandial peak 8.9 [1.7] vs. 15 [1.5] mmol/l, P < 0.01), and from 10:00 A.M., five subjects required treatment for hypoglycemia (nadir 1.9-2.9 mmol/l). None of the subjects had hypoglycemia after consumption of water. After consumption of wine, growth hormone secretion was significantly reduced between midnight and 4:00 A.M. (area under the curve 2.1 [1.1] vs. 6.5 [2.1] microg. l(-1) x h(-1), P = 0.04). There were no differences in insulin or other hormone levels. CONCLUSIONS: In type 1 diabetes, moderate consumption of alcohol in the evening may predispose patients to hypoglycemia after breakfast the next morning. This is associated with reduced nocturnal growth hormone secretion. Patients should be informed of this risk and advised regarding appropriate preventative measures.
Assuntos
Consumo de Bebidas Alcoólicas/sangue , Glicemia/metabolismo , Ritmo Circadiano/fisiologia , Diabetes Mellitus Tipo 1/sangue , Adulto , Área Sob a Curva , Glucagon/sangue , Hormônio do Crescimento Humano/sangue , Humanos , Hidrocortisona/sangue , Insulina/sangue , Masculino , Pessoa de Meia-Idade , VinhoRESUMO
BACKGROUND: Mutations in BRCA1 and BRCA2 account for approximately 50% of breast cancer families with more than four affected cases, whereas exonic mutations in p53, PTEN, CHK2 and ATM may account for a very small proportion. It was recently reported that an intronic variant of p53--G13964C--occurred in three out of 42 (7.1%) 'hereditary' breast cancer patients, but not in any of 171 'sporadic' breast cancer control individuals (P = 0.0003). If this relatively frequent occurrence of G13964C in familial breast cancer and absence in control individuals were confirmed, then this would suggest that the G13964C variant plays a role in breast cancer susceptibility. METHOD: We genotyped 71 familial breast cancer patients and 143 control individuals for the G13964C variant using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis. RESULTS: Three (4.2%; 95% confidence interval [CI] 0-8.9%) G13964C heterozygotes were identified. The variant was also identified in 5 out of 143 (3.5%; 95% CI 0.6-6.4%) control individuals without breast cancer or a family history of breast cancer, however, which is no different to the proportion found in familial cases (P = 0.9). CONCLUSION: The present study would have had 80% power to detect an odds ratio of 4.4, and we therefore conclude that the G13946C polymorphism is not a 'high-risk' mutation for familial breast cancer.
Assuntos
Neoplasias da Mama/genética , Genes p53/genética , Predisposição Genética para Doença/genética , Adulto , Estudos de Casos e Controles , Primers do DNA , Feminino , Humanos , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase , Polimorfismo Genético , Polimorfismo de Fragmento de RestriçãoRESUMO
The Diabetes Advisory System (DIAS) is a decision-support program developed to assist insulin dose adjustment in type 1 diabetes. In this paper, we show how it might be used to identify impaired absorption or omission of insulin in patients with poorly controlled blood glucose. An evaluation of glucose results from four outpatients with persistent hyperglycemia is presented (age 19-48 years with type 1 diabetes for 13-18 years of duration, HbA1c 9.4-13.6%). Each had completed a 4-day record of blood glucose (BG, pre-meal and bedtime), dietary (carbohydrate) intake, and insulin doses (with injection sites). From these data, DIAS modeled a glucose profile (simulated glucose, SG) for the same period. Qualitative assessments were made of differences between BG and SG, and selective reduction or complete removal of insulin doses where BG >> SG. Large improvements in modeling were attributed to either impaired absorption or omission of insulin. Confirmation of these problems was sought from the patients by detailed consultation and physical examination. Impaired insulin absorption was suspected in two patients, both having significant injection site abnormalities. Insulin omission was suspected in the other two subjects. Both had normal injection sites, and one admitted to missing doses. Following retraining, data from three patients showed noticeable improvements in overall modeling as well as glucose control. Using DIAS in the evaluation of patients with type 1 diabetes may highlight previously unrecognized injection site abnormalities or insulin dose omission. This could assist rational optimization of insulin therapy in cases of persistently poor glucose control.
Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/tratamento farmacológico , Quimioterapia Assistida por Computador , Insulina/uso terapêutico , Adulto , Glicemia/análise , Simulação por Computador , Sistemas de Apoio a Decisões Clínicas , Carboidratos da Dieta , Esquema de Medicação , Feminino , Hemoglobinas Glicadas/análise , Humanos , Insulina/administração & dosagem , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Cooperação do PacienteRESUMO
This is a summary report on samples of conidiating Neurospora species collected over three decades, in many regions around the world, primarily from burned vegetation. The genus is ubiquitous in humid tropical and subtropical regions, but populations differ from region to region with regard to which species are present. The entire collection, >4600 cultures from 735 sites, is listed by geographical origin and species. Over 600 cultures from 78 sites have been added since the most recent report. Stocks have been deposited at the Fungal Genetics Stock Center. New cultures were crossed to testers for species identification; evident mixed cultures were separated into pure strains, which were identified individually. New techniques and special testers were used to analyze cultures previously listed without species identification. The discussion summarizes what has been learned about species and natural populations, describes laboratory investigations that have employed wild strains, and makes suggestions for future work.
Assuntos
Neurospora/classificação , Neurospora/fisiologia , Cruzamentos Genéticos , Meios de Cultura , Ecossistema , Hibridização Genética , Técnicas de Tipagem Micológica , Neurospora/genética , Esporos Fúngicos/fisiologia , Clima TropicalRESUMO
Spore killer strains, found in Neurospora, provided the first recognized example of meiotic drive in fungi. In the present study, natural populations throughout the world were examined for the presence of killer strains and strains that are resistant to killing. In N. intermedia, Sk-2 and Sk-3 are present but are rare. Killer strains were found at only five sites, in Borneo, Java, and Papua New Guinea. Nonkiller strains that are resistant to killing by Sk-2 or Sk-3 are frequent in that part of the world where the killer strains are present, but resistant stains were not found in regions where killers are absent. In N. sitophila, Sk-1 killer strains are common in nature, but only 1 of 392 nonkiller strains was resistant. In N. crassa, no killer strain was found among >500, but widely scattered Sk-2-resistant strains were present, suggesting the past or present existence of killers.
Assuntos
Proteínas Fúngicas/genética , Neurospora/classificação , Neurospora/fisiologia , Esporos Fúngicos/fisiologia , Cruzamentos Genéticos , Ecossistema , Genes Fúngicos , Meiose , Neurospora/genéticaRESUMO
PURPOSE: Among women with early-stage breast cancer treated with lumpectomy and radiation therapy, 30% to 40% will develop metastatic disease, which is often fatal. A need exists therefore for biomarkers that distinguish patients at high risk of relapse. We performed a retrospective correlative analysis of BAG-1 protein expression in breast tumors derived from a cohort of early-stage breast cancer patients. PATIENTS AND METHODS: Archival paraffin blocks from 122 women with stages I to II breast cancer treated with lumpectomy and radiation therapy (median follow-up, 12.1 years) were analyzed by immunohistochemical methods using monoclonal antibodies recognizing BAG-1 and other biomarkers, including Bcl-2, estrogen receptor, progesterone receptor, p53, and HER2/Neu. Immunostaining data were correlated with distant metastasis-free survival (DMFS) and overall survival (OS). RESULTS: Cytosolic immunostaining for BAG-1 was upregulated in 79 (65%) of 122 invasive breast cancers (P <.001) compared with normal breast. Elevated BAG-1 was significantly associated with longer DMFS and OS, overall (stages 1 and II) and in node-negative (stage I only) patients, on the basis of univariate and multivariate analyses (DMFS, P =.005; OS, P =.01, in multivariate analysis of all patients; DMFS, P =.005; OS, P =.001, in multivariate analysis of node-negative patients). All other biomarkers failed to reach statistical significance in multivariate analysis. Clinical stage was an independent predictor of OS (P =.04) and DMFS (P =.02). CONCLUSION: These findings provide preliminary evidence that BAG-1 represents a potential marker of improved survival in early-stage breast cancer patients, independent of the status of axillary lymph nodes.
Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Proteínas de Transporte/análise , Adulto , Idoso , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/radioterapia , Terapia Combinada , Proteínas de Ligação a DNA , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Mastectomia Segmentar , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de TranscriçãoRESUMO
PURPOSE: The purpose of this study was to classify all ipsilateral breast tumor relapses (IBTR) in patients treated with conservative surgery and radiation therapy (CS+RT) as either new primary tumors (NP) or true local recurrences (TR) and to assess the prognostic and therapeutic implications of this classification. METHODS AND MATERIALS: Of the 1152 patients who have been treated at Yale-New Haven Hospital before 1990, 136 patients have experienced IBTR as their primary site of failure. These relapses were classified as either NP or TR. Specifically, patients were classified as NP if the recurrence was distinctly different from the primary tumor with respect to the histologic subtype, the recurrence location was in a different location, or if the flow cytometry changed from aneuploid to diploid. This information was determined by a detailed review of each patient's hospital and/or radiotherapy record, mammograms, and pathologic reports. RESULTS: As of 2/99, with a mean follow-up of 14. 2 years, the overall ipsilateral breast relapse-free rate for all 1152 patients was 86% at 10 years. Using the classification scheme outlined above, 60 patient relapses were classified as TR, 70 were classified as NP and 6 were unable to be classified. NP patients had a longer mean time to breast relapse than TR patients (7.3 years vs. 3.7 years, p < 0.0001) and were significantly younger than TR patients (48.9 years vs. 54.5 years, p < 0.01). Patients developed both TR and NP at similar rates until approximately 8 years, when TR rates stabilized but NP rates continued to rise. By 15 years following original diagnosis, the TR rate was 6.8% compared to 13.1% for NP. Of the patients who had been previously tested for BRCA1/2 mutations, 17% (8/52) had deleterious mutations. It is noteworthy that all patients with deleterious mutations had new primary IBTR, while patients without deleterious mutations had both TR and NP (p = 0.06). Ploidy was evenly distributed between TR and NP but NP had a significantly lower S phase fraction (NP 13.1 vs. TR 22.0, p < 0.05). The overall survival following breast relapse was 64% at 10 years and 49% at 15 years. With a mean follow-up of 10.4 years following breast relapse, patients with NP had better 10-year overall survival (TR 55% vs. NP 75%, p < 0.0001), distant disease-free survival (TR 41% vs. NP 85%, p < 0.0001), and cause-specific survival (TR 55% vs. NP 90%, p < 0.0001). CONCLUSION: It appears that a significant portion of patients who experience ipsilateral breast tumor relapse following conservative surgery and radiation therapy have new primary tumors as opposed to true local recurrences. True recurrence and new primary tumor ipsilateral breast tumor relapses have different natural histories, different prognoses, and, in turn, different implications for therapeutic management.
Assuntos
Neoplasias da Mama/diagnóstico , Recidiva Local de Neoplasia/diagnóstico , Segunda Neoplasia Primária/diagnóstico , Adulto , Fatores Etários , Idoso , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Mastectomia Segmentar , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Segunda Neoplasia Primária/patologia , Prognóstico , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Fatores de TempoRESUMO
AIMS: To assess knowledge about oral hypoglycaemic agents amongst patients with diabetes and non-specialist healthcare professionals. METHOD: An anonymous questionnaire was used in two centres to assess knowledge about oral agents amongst 261 patients with Type 2 diabetes mellitus (mean age 64 years) and 102 health professionals (including doctors, nurses and pharmacists). RESULTS: Only 15% of patients knew the correct mechanism of action of their medication and 62% took tablets correctly in relation to food. Only 10% of those taking a sulphonylurea knew it may cause hypoglycaemia and 20% of those taking metformin were aware of its gastrointestinal side-effects. Twenty per cent forgot to take their tablets at least once a week and 5% omitted tablets because of hyperglycaemia. Only 35% of patients recalled receiving advice about their medication with only 1% receiving written advice. The healthcare professionals showed important gaps in their knowledge on dosage timing and mechanism of action, particularly with respect to metformin and acarbose. CONCLUSION: It is concluded that patients' and professionals' knowledge of oral hypoglycaemic agents is poor. More appropriate advice and information to patients from prescribers may improve patient understanding and hence compliance. Community pharmacists are ideally placed to reinforce this information.
Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/reabilitação , Conhecimentos, Atitudes e Prática em Saúde , Hipoglicemiantes/uso terapêutico , Enfermeiras e Enfermeiros , Farmacêuticos , Médicos , Acarbose/uso terapêutico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Metformina/uso terapêutico , Pessoa de Meia-Idade , Compostos de Sulfonilureia/uso terapêutico , Inquéritos e QuestionáriosRESUMO
We have described a peripheral blood mononuclear cell (PBMC) culture system in which control of endogenous virus and resistance to exogenous HIV-1 correlates with low viremia among HIV-1-positive people. Nineteen patients remained consistently resistant or susceptible for more than 5 years of follow-up. On the fifth year, 5 consistently susceptible volunteers with high viral loads began receiving highly active anti-retroviral therapy (HAART). After >6 months on HAART, 5 of 5 became completely or predominantly resistant on four visits over the next 6 months. Among HIV-1-positive donors, we had never observed reversal of PBMC phenotype from consistently susceptible to consistently resistant. Resistance correlated with suppression of plasma viremia and rebound in CD4+ T-cell counts and percentages. When resistant PBMCs were challenged after CD8+ T-cell depletion, 38 of 41 and 40 of 59 cultures became susceptible to HIV-1MN and HIV-1BaL, respectively. After combined CD8+ T-cell depletion and antibody neutralization of beta-chemokines, 16 of 18 cultures became susceptible to HIV-1BaL. Overall, the finding that >90% of these cultures depleted of relevant antiviral effector arms could become infected indicates resistance was not due to residual antiretroviral drug metabolites in vitro. For 2 volunteers who discontinued therapy because of side effects, pretreatment viral load correlated with loss of in vitro resistance and viral rebound. In addition to resistance to laboratory strains of HIV-1, all patients developed resistance to at least one of two CCR5-tropic, clade B primary isolates: HIV-1P15 and HIV-1P27.
Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1/imunologia , Macrófagos/efeitos dos fármacos , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/virologia , Anticorpos/farmacologia , Contagem de Linfócito CD4 , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular , Quimiocinas/antagonistas & inibidores , Quimiocinas/imunologia , Estudos de Coortes , Quimioterapia Combinada , Proteína do Núcleo p24 do HIV/análise , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/isolamento & purificação , Humanos , Técnicas In Vitro , Macrófagos/virologia , Síndrome de Abstinência a Substâncias/imunologia , Carga Viral , ViremiaRESUMO
PURPOSE: The purpose of this study was to determine the prognostic significance of cyclin D1 (cycD1) levels in ipsilateral breast tumor recurrence (IBTR) following lumpectomy and radiation therapy. METHODS AND MATERIALS: A total of 98 patients (49 patients with IBTR and 49 matched cases without IBTR) selected from our conservatively treated breast cancer population served as the patient population for the current study. All patients were treated with lumpectomy followed by radiation therapy to the intact breast to a total median dose of 64 Gy. The patients were followed in our clinic with a median follow-up of 13 years. Immunohistochemical analysis of cycD1 in these 98 early-stage breast cancer patients was performed using a polyclonal antibody generated against the human cycD1 protein. All clinical, pathologic, and molecular variables were entered into a computerized data base for statistical analysis. RESULTS: Low levels of immunohistochemically detected cycD1 protein correlated with IBTR (p = 0.001), but there was no association between cycD1 protein levels and metastatic disease, axillary lymph node involvement, distant disease-free survival (DDFS), and overall survival (OS). Subgroup analysis revealed that for early breast tumor relapses (within 4 years of initial breast tumor diagnosis), low levels of cycD1 were associated with IBTR (p = 0.004), but cycD1 expression was not prognostic for IBTR from breast cancer patients with late relapses (p = NS). CONCLUSION: These studies provide in vivo evidence for the prognostic and biologic significance of cycD1 expression in determining response to radiation therapy in breast cancer patients.
Assuntos
Neoplasias da Mama/metabolismo , Ciclina D1/metabolismo , Proteínas de Neoplasias/metabolismo , Recidiva Local de Neoplasia/metabolismo , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Estudos de Casos e Controles , Núcleo Celular/metabolismo , Terapia Combinada , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Mastectomia Segmentar , Pessoa de Meia-Idade , Prognóstico , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismoRESUMO
Recent laboratory experiments have demonstrated that cyclin D1 levels (cycD1) can influence radiosensitivity. The purpose of the current study is to evaluate the prognostic significance of cycD1 for local recurrence in early-stage larynx cancer treated with primary radiation therapy. The study was conducted using a matched case-control design in 60 early-stage (T1-T2/N0) larynx cancer patients. All patients had squamous cell carcinoma of the larynx and were treated with primary radiation to a total median dose of 66 Gy in daily fractions of 2 Gy, without surgery or chemotherapy. Thirty patients who suffered a local relapse in the larynx after treatment served as the index case population. These 30 cases were matched by age, sex, site (glottic vs. supraglottic), radiation therapy technique/dose, and follow-up, to 30 control patients who did not experience a local relapse. Immunohistochemical staining from cycD1 was performed on the paraffin-embedded specimens. The pathologist, blinded to the clinical information, scored each of the specimens on a four-point intensity scale (0 = no stain, 1 = faint, 2 = moderate, 3 = strong) and percent distribution. Patients were considered to be positive for cyclin D1 if the staining was 2+ or greater with a percent distribution of at least 5%. By design of the study, the two groups were evenly balanced with respect to age, sex, stage, radiation dose, and follow-up. CycD1 levels correlated with proliferating cell nuclear antigen levels. Low levels of cycD1 significantly correlated with local relapse; 19/30 (63%) of the index cases stained negative, while only 10/30 (33%) of the control cases stained negative (P = 0.03). These data suggest that low levels of cycD1 correlate with relatively radioresistant early-stage larynx carcinoma. With larger more confirmatory clinical and laboratory data, this data may have significant clinical implications. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 22-28 (2000).
Assuntos
Carcinoma de Células Escamosas/química , Ciclina D1/análise , Neoplasias Laríngeas/química , Proteínas de Neoplasias/análise , Recidiva Local de Neoplasia/química , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Estudos de Casos e Controles , Feminino , Humanos , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/radioterapia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Antígeno Nuclear de Célula em Proliferação/análise , Dosagem RadioterapêuticaRESUMO
BACKGROUND: The p53 tumor suppressor gene encodes a nuclear phosphoprotein that is thought to be important to cell cycle regulation and DNA repair and that also may regulate induction of apoptosis by ionizing radiation. Somatic p53 gene mutations occur in 30-50% of breast carcinomas and are associated with poor prognosis. Mutations in the p53 gene result in prolonged stability of the protein that can be detected by immunohistochemical techniques. In a matched case-control study of breast carcinoma patients with ipsilateral breast tumor recurrence (IBTR) following lumpectomy and radiation therapy, the authors investigated the frequency and prognostic significance of somatic p53 mutations as well as the clinical characteristics of patients with these mutations. METHODS: Between 1973 and 1995, there were 121 breast carcinoma patients with IBTR following lumpectomy and radiation therapy, and the authors identified 47 patients in whom the paraffin embedded tissue blocks from the primary breast tumors were available for further molecular analysis. Forty-seven control breast carcinoma patients from the breast carcinoma data base were individually matched to the index cases who did not have IBTR for age, treatment date, follow-up, histology, margin status, radiation dose, and adjuvant treatment. Immunohistochemistry using a monoclonal antibody to mutant p53 protein was used to determine mutant p53 protein overexpression in breast tumors and appropriately scored. RESULTS: A total of 12 of 47 tumor specimens (26%) from index patients with breast tumor relapses demonstrated mutant p53 protein overexpression, whereas only 4 of 47 specimens from controls (9%) demonstrated high mutant p53 immunoreactivity (P = 0.02). The authors found that 9 of 23 patients (39%) with early breast tumor recurrences (recurrences within 4 years of diagnosis) had overexpression of mutant p53 protein, whereas only 1 of 23 control cases (4%) had high mutant p53 protein immunoreactivity (P = 0.003). In contrast, index cases from patients with late breast tumor relapses (more than 4 years after diagnosis), which are more likely to represent de novo breast tumors, and control cases from the breast carcinoma data base without IBTR had similar levels of mutant p53 protein overexpression (P = not significant). The 10-year distant disease free survival for patients with mutant p53 protein was 48%, compared with 67% for breast carcinoma patients without detection of mutant p53 protein (P = 0. 08). The authors found that 13 of 14 primary breast tumors (93%) with mutant p53 protein overexpression were estrogen receptor negative (P = 0.01) and 11 of 14 (79%) were progesterone receptor negative (P = not significant). CONCLUSIONS: In a matched case-control study, overexpression of mutant p53 protein has prognostic significance with respect to IBTR following lumpectomy and radiation therapy. Breast tumors with p53 mutations are generally estrogen receptor negative and are associated with compromised distant disease free survival.
Assuntos
Neoplasias da Mama/genética , Mastectomia Segmentar , Mutação , Recidiva Local de Neoplasia/genética , Proteína Supressora de Tumor p53/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Estudos de Casos e Controles , Terapia Combinada , Feminino , Humanos , Imuno-Histoquímica , Recidiva Local de Neoplasia/metabolismo , Prognóstico , Dosagem Radioterapêutica , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Taxa de SobrevidaRESUMO
Previous studies have determined that the frequency of germ-line p53 mutations in familial breast cancer patients is 1% or less, but these reports have not investigated the importance of polymorphic intron base changes in the p53 gene. Therefore, we investigated the frequency of both exon and intron germ-line p53 base changes in 42 breast cancer patients with a strong family history of breast cancer. The mean age of presentation of these patients was 44.0 years (range, 29-69), and 12 of 42 (29%) were of known Ashkenazi ancestry. Purified DNA obtained from the 42 index cases was screened for germ-line p53 mutations in exons 2-11 and surrounding introns using a combination of intron based primers for PCR-single strand conformation polymorphism analysis, direct sequencing, and microarray sequencing using the Affymetrix p53 gene chip methodology. Morphological analysis of apoptosis and cell survival determination were performed on EBV-immortalized lymphoblastoid cell lines from two patients with the p53 intron 6 mutation. A germ-line mutation in the p53 gene at nucleotide 13964 with a G to C base change (13964GC) was identified in 3 of 42 (7.1%) hereditary breast cancer patients. Two patients were heterozygous for this mutation, and one patient had a homozygous mutation. In comparison, 0 of 171 (0%) of sporadic breast cancer patients had the p53 13964GC mutation (P = 0.0003). We found that 0 of 42 (0%) of these hereditary breast cancer patients had other germ-line p53 mutation in exons 2-11. However, pedigree analysis demonstrated that all three patients had strong family histories of multiple types of cancers consistent with Li-Fraumeni syndrome but with late age of onset. Comprehensive BRCA1 and BRCA2 nucleotide analysis from patients with the p53 13964GC mutation revealed no concomitant deleterious BRCA1 or BRCA2 mutations, although they were found in the other hereditary breast cancer patients. Functional analysis of two immortalized lymphoblastoid cell lines derived from patients with the p53 13964GC mutation demonstrated prolonged in vitro survival in response to cisplatinum treatment and showed decreased chemotherapy-induced apoptosis. Immunohistochemical analysis of breast tumors from these patients revealed high levels of mutant p53 protein, suggesting a functional mutation in the p53 gene. In summary, we have identified a single p53 intron mutation in familial breast cancer patients that is present at elevated frequency and has functional activity.
Assuntos
Neoplasias da Mama/genética , Genes p53 , Mutação em Linhagem Germinativa , Íntrons , Adulto , Feminino , Genótipo , Humanos , Síndrome de Li-Fraumeni/genética , Pessoa de Meia-IdadeRESUMO
PURPOSE: Breast cancer patients treated conservatively with lumpectomy and radiation therapy (LRT) have an estimated lifetime risk of local relapse (ipsilateral breast tumor recurrence [IBTR]) of 10% to 15%. For breast cancer patients carrying BRCA1 or BRCA2 (BRCA1/2) mutations, the outcome of treatment with LRT with respect to IBTR has not been determined. In this study, we estimate the frequency of BRCA1/2 mutations in a study of breast cancer patients with IBTR treated with LRT. PATIENTS AND METHODS: Between 1973 and 1994, there were 52 breast cancer patients treated with LRT who developed an IBTR within the prior irradiated breast and who were willing to participate in the current study. From our database, we also identified 52 control breast cancer patients treated with LRT without IBTR. The control patients were individually matched to the index cases with respect to multiple clinical and pathologic parameters. Lymphocyte DNA specimens from all 52 locally recurrent patients and 15 of the matched control patients under age 40 were used as templates for polymerase chain reaction amplification and dye-primer sequencing of exons 2 to 24 of BRCA1, exons 2 to 27 of BRCA2, and flanking intron sequences. RESULTS: After LRT, eight (15%) of 52 breast cancer patients had IBTR with deleterious BRCA1/2 mutations. By age, there were six (40%) of 15 patients with IBTR under age 40 with BRCA1/2 mutations, one (9.0%) of 11 between ages 40 and 49, and one (3.8%) of 26 older than age 49. In comparison to the six (40%) of 15 of patients under age 40 with IBTR found to have BRCA1/2 mutations, only one (6.6%) of 15 matched control patients without IBTR and had a BRCA1/2 mutation (P =.03). The median time to IBTR for patients with BRCA1/2 mutations was 7.8 years compared with 4.7 years for patients without BRCA1/2 mutations (P =.03). By clinical and histologic criteria, these relapses represented second primary tumors developing in the conservatively treated breast. All patients with BRCA1/2 mutations and IBTR underwent successful surgical salvage mastectomy at the time of IBTR and remain alive without evidence of local or systemic progression of disease. CONCLUSION: In this study, we found an elevated frequency of deleterious BRCA1/2 mutations in breast cancer patients treated with LRT who developed late IBTR. The relatively long time to IBTR, as well as the histologic and clinical criteria, suggests that these recurrent cancers actually represent new primary breast cancers. Early onset breast cancer patients experiencing IBTR have a disproportionately high frequency of deleterious BRCA1/2 mutations. This information may be helpful in guiding management in BRCA1 or BRCA2 patients considering breast-conserving therapy.
Assuntos
Neoplasias da Mama/genética , Genes BRCA1/genética , Proteínas de Neoplasias/genética , Recidiva Local de Neoplasia/genética , Fatores de Transcrição/genética , Adulto , Idade de Início , Proteína BRCA2 , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Feminino , Mutação em Linhagem Germinativa , Humanos , Mastectomia Segmentar , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente , Medição de Risco , Resultado do TratamentoRESUMO
Dysregulation of normal programmed cell death mechanisms plays an important role in the pathogenesis and progression of breast cancer, as well as in responses of tumors to therapeutic intervention. Overexpression of anti-apoptotic members of the Bcl-2 family such as Bcl-2 and Bcl-X(L) has been implicated in cancer chemoresistance, whereas high levels of pro-apoptotic proteins such as Bax promote apoptosis and sensitize tumor cells to various anticancer therapies. Though the mechanisms by which Bcl-2 family proteins regulate apoptosis are diverse, ultimately they govern decision steps that determine whether certain caspase family cell death proteases remain quiescent or become active. To date, approximately 17 cellular homologs of Bcl-2 and at least 15 caspases have been identified in mammals. Other types of proteins may also modulate apoptotic responses through effects on apoptosis-regulatory proteins, such as BAG-1-a heat shock protein 70 kDa (Hsp70/Hsc70)-binding protein that can modulate stress responses and alter the functions of a variety of proteins involved in cell death and division. In this report, we summarize our attempts thus far to explore the expression of several Bcl-2 family proteins, caspase-3, and BAG-1 in primary breast cancer specimens and breast cancer cell lines. Moreover, we describe some of our preliminary observations concerning the prognostic significance of these apoptosis regulatory proteins in breast cancer patients, contrasting results derived from women with localized disease (with or without node involvement) and metastatic cancer.
Assuntos
Apoptose , Neoplasias da Mama/patologia , Proteínas de Neoplasias/biossíntese , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Caspases/biossíntese , Caspases/genética , Proteínas de Ligação a DNA , Feminino , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Genes bcl-2 , Humanos , Pessoa de Meia-Idade , Proteína de Sequência 1 de Leucemia de Células Mieloides , Proteínas de Neoplasias/genética , Gravidez , Prognóstico , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/genética , Fatores de Transcrição , Células Tumorais Cultivadas , Proteína X Associada a bcl-2 , Proteína bcl-XRESUMO
The AP-2 transcription factors are required for normal growth and morphogenesis during mammalian development. Previous in vitro studies have also indicated that the AP-2 family of proteins may be involved in the etiology of human breast cancer. The AP-2 genes are expressed in many human breast cancer cell lines, and critical AP-2-binding sites are present in both the ERBB-2 (HER2/neu) and estrogen receptor promoters. We have now characterized immunological reagents that enable specific AP-2 family members, including AP-2alpha and AP-2gamma, to be detected in human breast cancer epithelium. Data obtained with these reagents demonstrate that whereas AP-2alpha and AP-2gamma are both present in benign breast epithelia, there is a significant up-regulation of AP-2gamma expression in breast cancer specimens (P = 0.01). There was also a significant correlation between the presence of the AP-2alpha protein and estrogen receptor expression (P = 0.018) and between specimens containing both AP-2alpha/AP-2gamma proteins and ERBB-2 expression (P = 0.003). Furthermore, we detected an association (P = 0.04) between the expression of AP-2gamma and the presence of an additional signal transduction molecule implicated in breast cancer, the insulin-like growth factor I receptor. Analysis of the proximal promoter of the insulin-like growth factor I receptor revealed a novel AP-2-binding site. Thus, AP-2 proteins may directly regulate the transcription of this growth factor receptor. Taken together, these data strongly support a role for the AP-2 gene family in the control of cell growth and differentiation in breast cancer.
Assuntos
Neoplasias da Mama/metabolismo , Proteínas de Ligação a DNA/biossíntese , Receptores de Fatores de Crescimento/fisiologia , Transdução de Sinais/fisiologia , Fatores de Transcrição/biossíntese , Sítios de Ligação , Mama/metabolismo , Epitélio/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Prognóstico , Regiões Promotoras Genéticas/fisiologia , Receptor ErbB-2/biossíntese , Receptor IGF Tipo 1/genética , Receptores de Estrogênio/biossíntese , Receptores de Fatores de Crescimento/biossíntese , Receptores de Fatores de Crescimento/genética , Receptores de Progesterona/biossíntese , Fator de Transcrição AP-2 , Células Tumorais Cultivadas , Regulação para Cima/fisiologiaRESUMO
BACKGROUND: The purpose of this study was to evaluate the relationships among young age at diagnosis, family history status, and local recurrence in breast cancer patients treated with lumpectomy and radiation therapy. METHODS: Between January 1970 and December 1990, 984 early-stage breast cancer patients were treated with conservative surgery and radiation therapy at Yale-New Haven Hospital. All patient data, including demographics, staging information, treatment, and outcome variables were entered into a computerized database. The current study focused on the relationships between young age, family history, and local relapse. A group of 52 patients who experienced a local recurrence in the conservatively treated breast and 52 matched control patients who had not experienced a local recurrence were asked to participate in a study to determine whether local recurrence was associated with family history. Detailed family history interviews were conducted, and pedigrees were analyzed by a genetic counselor who was blind to the clinical history of the patients. RESULTS: As of September 1997, with a median follow-up of 12.3 years for the 984 patients in the database, the overall actuarial 10-year survival is 73%, and the 10-year distant metastasis-free survival is 78%. Of the 984 patients, 112 have experienced a local relapse in the conservatively treated breast, resulting in a 10-year actuarial breast relapse rate of 15%. The 10-year survival after breast relapse is 69%. Patient age tested as a continuous variable correlated strongly with ipsilateral breast tumor relapse. Using age 40 as a cutpoint, patients aged 40 years or less had a significantly higher local relapse rate than patients older than 40 years (P < 0.001). Although the relationship between local relapse and young age was strong, no association was found between family history and local relapse in the detailed family history study. CONCLUSIONS: Young age at diagnosis was a significant prognostic factor for local relapse. In a detailed family history study using a case-control design, no significant differences in family history status were found between patients who had experienced a local relapse and patients who had not.