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1.
Eur J Cancer ; 38(11): 1466-73, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12110492

RESUMO

Few data are available to help predict which older cancer patient is at risk of developing chemotherapy-related toxicity. This study was a pilot for a project designing a predictive risk score. Chemotherapy patients aged 70 years and older were prospectively enrolled. Chemotherapies were adjusted for their published toxicity. 60 patients were enrolled, 59 were evaluable. Mean dose-intensity was 90.3%, range 33.3-129.0%. 47% of the patients experienced grade 4 haematological and/or grade 3-4 non-haematological toxicity. Published toxicity (MAX2), diastolic blood pressure, marrow invasion and lactate dehydrogenase (LDH) were all associated with toxicity (P<0.1); Body Mass Index, previous chemotherapy, red blood cells, platelets, polymedication with dose-intensity; and polymedication with FACT-G change. After adjustment for the published toxicity, the variables retained their significance, except for LDH and polymedication (for dose-intensity). Although the size of this pilot study imposes a cautious interpretation, patient-related and chemotherapy-related variables correlated independently with toxicity. Designing a composite predictive score to use in assessing the toxicity of multiple chemotherapy regimens therefore appears to be a valid undertaking.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Avaliação Geriátrica , Humanos , Masculino , Projetos Piloto , Valor Preditivo dos Testes , Estudos Prospectivos
2.
Brain Res Bull ; 56(2): 79-85, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11704343

RESUMO

The important role that neural tissue fatty acid composition plays in neurodevelopment and various pathological states is increasingly recognized. However, there are limited data regarding the fatty acid composition of normal human brain at various ages. The purpose of this study was to describe human cerebral cortex fatty acid composition from ages 2 to 88 years. The relationship between cerebral cortex and erythrocyte fatty acid composition was also investigated. Samples of frontal cerebral cortex and of erythrocytes were obtained from 58 human subjects on whom autopsies were performed. The mean age of subjects was 40 +/- 29 years, with a range of 2 to 88 years. The fatty acid composition of tissues was determined, and linear regression models were used to describe the relationship between age and the fatty acid composition of cerebral cortex and erythrocytes. The data were bilinear, with changes occurring after the approximate age of 18 years. Therefore, the cohort was divided into subjects with ages < or =18 and >18 years. In the younger group, the polyunsaturated fatty acids generally decreased with age, with the exception of 22:6n3, which demonstrated a significant increase. The level of mono-unsaturated fatty acids, in contrast, generally increased to the age of 18 years. Several of the polyunsaturated fatty acids also decreased with age in the older cohort, particularly 20:4n6. The levels of 18:2n6, however, increased significantly with age in the older cohort. Among subjects < or =18 years of age, there was no significant relationship between cerebral cortex and erythrocyte fatty acid levels. In the older cohort, there was a significant relationship between brain and erythrocyte levels for several fatty acids, particularly 16:0. These data demonstrate that levels of cerebral cortex fatty acids change from early childhood through late adulthood, and indicate that the levels of several erythrocyte fatty acids may be useful in predicting brain fatty acid levels in adults.


Assuntos
Envelhecimento/fisiologia , Membrana Celular/metabolismo , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/metabolismo , Eritrócitos/metabolismo , Ácidos Graxos/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Humanos , Lactente , Camundongos , Pessoa de Meia-Idade , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/fisiopatologia , Valor Preditivo dos Testes , Análise de Regressão
3.
Curr Opin Genet Dev ; 11(5): 513-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11532392

RESUMO

Over the past year, significant new insights have been gained in our understanding of the lineage determination of red blood cells. In particular, evidence has emerged demonstrating that cross-antagonism of lineage-specific transcription factors plays an important role in determining cell phenotype by actively repressing alternate lineage gene programs.


Assuntos
Linhagem da Célula , Hematopoese/genética , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Fatores de Transcrição/metabolismo , Animais , Proteínas de Transporte/metabolismo , Diferenciação Celular , Proteínas de Ligação a DNA/metabolismo , Fatores de Ligação de DNA Eritroide Específicos , Humanos , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Transativadores/metabolismo
4.
Stat Med ; 20(14): 2091-7, 2001 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-11439423

RESUMO

Clinical studies in which a major objective is to produce Kaplan-Meier estimates of survival probabilities should be designed to produce those estimates with a desired prespecified precision as measured by their standard errors. By considering the Peto and Greenwood formulae for the estimated standard error of the Kaplan-Meier estimate and replacing their constituents with expected values based on the study's design parameters, formulae for projected standard errors can be produced. These formulae are shown, through simulations, to be quite accurate.


Assuntos
Ensaios Clínicos como Assunto/métodos , Análise de Sobrevida , Simulação por Computador , Humanos
5.
J Am Acad Dermatol ; 44(5): 762-6, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11312421

RESUMO

BACKGROUND: In patients with melanoma, lymph node staging information is obtainable by the surgical techniques of lymphatic mapping and sentinel lymph node (SLN) biopsy. Although no survival benefit has been proven for the procedure, the staging information is useful in identifying patients who may benefit from further surgery or adjuvant therapy. Currently, however, it is not being recommended for patients with thick melanomas (> 3-4 mm). The risk of hematogenous dissemination is considered too great in these patients. Recent studies indicate, however, that a surprising number of patients with thick melanomas become long-term survivors, and the lymph node status may be predictive. None of the conventional microscopic features used to gauge prognosis in patients with melanoma have proven helpful in distinguishing the survivors with thick melanoma from those who will die of their disease. OBJECTIVE: Our purpose was to evaluate the influence of SLN histology and other microscopic parameters on survival of patients with thick melanomas. METHODS: A computerized patient database at the Cutaneous Oncology Clinic at H. Lee Moffitt Cancer Center was accessed to obtain records on patients with melanomas thicker than 3.0 mm (AJCC T3b). A retrospective analysis was conducted with attention paid to histologic variables, sentinel node status, and survival. Survival curves were constructed with the Kaplan-Meier method, and a Cox-Mantel rank testing was used to establish statistical significance. RESULTS: Between 1991 and 1999, 201 patients were diagnosed with melanoma thicker than 3.0 mm, and 180 were alive at an average follow-up of 51 months. Of these, 166 were alive without disease. The mean overall and disease-free survival rates were 78% and 66%, respectively. There was a statistically significant difference in disease-free survival (3-year) between SLN-positive and SLN-negative patients (37% vs 73%, respectively; P =.02). The overall survival (3-year) for the SLN-positive patients was less than the node-negative patients (70% vs 82%), but it was not statistically significant (P =.08). The disease-free survival for patients with ulcerated lesions was less than for nonulcerated lesions (77% vs 93%, P =.05). None of the other histologic parameters studied, including Breslow thickness, Clark level, mitotic rate, or regression, had an influence on the overall or disease-free survival in this group of patients with thick tumors. CONCLUSIONS: The results indicate that the SLN node status is predictive of disease-free survival for patients with thick melanomas. A surprising number of patients in the study were free of disease after prolonged follow-up. None of the histologic features of the primary tumor were helpful in predicting outcome, except for ulceration. SLN biopsy appears to be justified for prognostic purposes in patients with thick melanomas.


Assuntos
Melanoma/mortalidade , Melanoma/secundário , Biópsia de Linfonodo Sentinela/normas , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Intervalo Livre de Doença , Feminino , Florida/epidemiologia , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Análise de Sobrevida
6.
Oncogene ; 19(47): 5338-47, 2000 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-11103935

RESUMO

Upregulation of the cyclin-dependent kinase inhibitor p21WAF1/CIP1 and subsequent cell growth arrest or senescence is one mechanism by which normal cells are believed to respond to stress induced by the constitutively activated GTPase Ras. We hypothesize that in the absence of p21, the onset of Ras-dependent oncogenesis is accelerated. To test this hypothesis, we crossed MMTV/v-Ha-ras transgenic mice into a p21-deficient background. By 63 days of age, all 8 ras/p21-/- mice developed either malignant (mammary and/or salivary adenocarcinomas) or benign (Harderian hyperplasia) tumors. In contrast, by the same age, only one out of nine of the ras/p21+/+ mice developed a tumor. Furthermore, by 94 days of age, half of the ras/p21-/- mice, but none of the ras/p21+/+ mice, developed mammary tumors. p21-deficiency also accelerated the development of salivary (T50=66 days for ras/p21-/- vs T50=136 days for ras/p21+/+) and Harderian (T50=52 days for ras/p21-/- vs T50>221 days for ras/p21+/+) tumors. Furthermore, two out of the eight ras/p21-/- mice had metastatic lesions, one in its lungs, the other in its abdomen. None of the nine ras/p21+/+ mice had metastatic lesions. By 4 months of age, the mammary tumor multiplicity was 10-fold greater in ras/p21-/- (average 3.40 tumors/mouse) than in ras/p21+/+ (average 0.33 tumor/mouse) mice. However, once the tumors appeared, their growth rate, apoptosis level, and mitotic index were not affected by the loss of p21, suggesting that loss of p21 is critical in early but not late events of Ras oncogenesis. Altogether, the results show that tumor onset in MMTV/v-Ha-ras mice is p21-dependent with loss of p21 associated with earlier tumor appearance and increased tumor multiplicity and aggressiveness.


Assuntos
Carcinoma Ductal de Mama/fisiopatologia , Ciclinas/fisiologia , Genes ras/fisiologia , Neoplasias Mamárias Animais/fisiopatologia , Proteína Oncogênica p21(ras)/fisiologia , Adenocarcinoma/etiologia , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma/fisiopatologia , Animais , Carcinoma Ductal de Mama/etiologia , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patologia , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/genética , Modelos Animais de Doenças , Feminino , Expressão Gênica , Masculino , Neoplasias Mamárias Animais/etiologia , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/patologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Proteína Oncogênica p21(ras)/genética , Neoplasias das Glândulas Salivares/etiologia , Neoplasias das Glândulas Salivares/genética , Neoplasias das Glândulas Salivares/patologia , Neoplasias das Glândulas Salivares/fisiopatologia
7.
Ann Clin Lab Sci ; 30(3): 239-47, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10945563

RESUMO

Gastrointestinal stromal tumors are a heterogeneous group of mesenchymal neoplasms of the gastrointestinal tract in which routine histopathological evaluation fails to reveal definitive evidence of differentiation. Given the heterogeneity in clinical presentation and the frequent morphological overlap, the biological behavior of these neoplasms is difficult to predict. We have evaluated, by Cox Proportional Hazards Regression Analysis, the clinicopathological features of 51 malignant gastrointestinal stromal tumors to identify predictors of survival. In the univariate analysis, survival inversely correlated with size, number of mitoses, and patient's age. In the multivariate analysis, only the degree of necrosis and phenotypic differentiation toward smooth muscle were found to be indicators of poor prognosis. Based on these results, a simple classification scheme for gastrointestinal stromal tumors is proposed. This classification appears to have great prognostic value for these tumors, and may be useful in guiding therapeutic management.


Assuntos
Neoplasias do Colo/patologia , Neoplasias Gastrointestinais/patologia , Neoplasias Intestinais/patologia , Neoplasias Gástricas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Neoplasias do Colo/mortalidade , Feminino , Neoplasias Gastrointestinais/mortalidade , Humanos , Imuno-Histoquímica , Neoplasias Intestinais/mortalidade , Masculino , Pessoa de Meia-Idade , Índice Mitótico , Necrose , Variações Dependentes do Observador , Prognóstico , Neoplasias Gástricas/mortalidade , Células Estromais/patologia , Taxa de Sobrevida
8.
Otolaryngol Head Neck Surg ; 123(3): 211-7, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10964293

RESUMO

Hypothyroidism is a well-documented complication after treatment of head and neck cancer and is particularly significant among patients undergoing laryngectomy. The objective of this study was the identification of factors associated with the development of hypothyroidism in this population. Records of 136 patients treated with laryngectomy were retrospectively reviewed in an attempt to define a risk factor profile for patients in whom hypothyroidism is most likely to develop after laryngectomy. The Cox proportional hazards model was used to identify factors significantly related to an increased risk for development of hypothyroidism. The actuarial method was used to estimate the period of greatest risk for the development of hypothyroidism. Increased risks were found for patients who were female (P = 0.0049), received preoperative radiation therapy (P = 0.0022), had invasion of the thyroid gland by tumor (P = 0.0003), had presence of cervical metastases (P = 0.0022), and had postoperative fistula (P = 0.0095). From the actuarial method, we estimated that the period of time when patients were at greatest risk for development of hypothyroidism was between 0 and 14 months after surgical intervention. Wound complications were twice as frequent in hypothyroid patients. Perioperative awareness of risk factors associated with the development of hypothyroidism in patients undergoing laryngectomy allows for early recognition and management of hypothyroidism and may reduce the number of complications related to wound healing and fistula.


Assuntos
Hipotireoidismo/etiologia , Neoplasias Laríngeas/cirurgia , Laringectomia , Complicações Pós-Operatórias , Idoso , Neoplasias Encefálicas/patologia , Feminino , Humanos , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/radioterapia , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Fatores de Tempo
9.
Leukemia ; 14(5): 830-40, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10803514

RESUMO

CD95 (Fas/APO-1) is a member of the TNFR superfamily that induces apoptosis following cross-linking with its cognate ligand, CD95L (FasL/APO-1L) or agonist antibody. The human myeloma cell line, RPMI 8226, has limited sensitivity to CD95-mediated apoptosis, with a maximum of 65% of the population responding. To determine the source of the limited sensitivity to CD95-mediated apoptosis, we isolated multiple clones from the RPMI-8226 cell line by limiting dilution. Analysis of these clones demonstrated that sensitivity to CD95-mediated cell death directly correlated with CD95 expression. Clones with high levels of CD95 expression had greater than 90% cell death, whereas cells with low levels of expression had less than 10% cell death. In contrast, no correlative differences were identified for other members of the DISC complex, or for members of the anti-apoptotic Bcl-2 family. We further examined the sensitivity of the 8226 clones to various cytotoxic agents. Although modest clonal variability was demonstrated in response to the chemotherapeutic drugs, doxorubicin, etoposide (VP-16), and vincristine, there was no correlation between CD95 function and sensitivity to chemotherapeutic drugs. These results indicate that in this cell line, receptor expression is rate limiting in CD95-mediated apoptosis, whereas CD95 expression was not a determinant in drug-induced programmed cell death.


Assuntos
Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Mieloma Múltiplo/patologia , Transcrição Gênica , Receptor fas/genética , Caspase 3 , Caspase 8 , Caspase 9 , Caspases/genética , Caspases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Clonais , Doxorrubicina/toxicidade , Etoposídeo/toxicidade , Citometria de Fluxo , Humanos , Células Tumorais Cultivadas , Vincristina/toxicidade , Receptor fas/fisiologia
10.
Ann Clin Lab Sci ; 29(4): 308-15, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10528831

RESUMO

BACKGROUND: The differential diagnosis between atypical endometrial hyperplasia and endometrial carcinoma is often difficult and based on controversial criteria. Cell kinetic parameters may be helpful. DESIGN: Cell proliferation, apoptosis and Bcl-2 expression were evaluated in benign endometrium, non atypical and atypical endometrial hyperplasia and endometrial carcinoma. The results were compared by one way analysis of variance and Bonferroni T tests. RESULTS: Cell proliferation was significantly higher (p < 0.01) in endometrial adenocarcinoma (25.6 percent) than in atypical hyperplasia (17.1 percent) and non-atypical hyperplasia (7.5 percent) of the endometrium. Apoptosis was observed in 12.3 percent of endometrial adenocarcinomas and less frequently in atypical hyperplasia (7.4 percent) and non-atypical hyperplasia of the endometrium (5.8 percent). Bcl-2 expression was significantly lower (p < 0.002) in endometrial adenocarcinoma (1.7 percent) than in atypical hyperplasia (4.2 percent) and non-atypical hyperplasia (5.3 percent) of the endometrium. In benign endometrium, cell proliferation and Bcl-2 expression were significantly higher during the proliferative phase while the rate of apoptosis was significantly higher during the secretory phase. CONCLUSIONS: Our data suggests that cell proliferation, apoptosis and Bcl-2 expression could be helpful when distinguishing endometrial carcinoma from non-atypical or atypical endometrial hyperplasia.


Assuntos
Hiperplasia Endometrial/patologia , Neoplasias do Endométrio/patologia , Citometria por Imagem/métodos , Adulto , Idoso , Apoptose , Divisão Celular , Ciclina D1/análise , Diagnóstico Diferencial , Hiperplasia Endometrial/metabolismo , Neoplasias do Endométrio/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Antígeno Ki-67/análise , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Urology ; 53(5): 931-8, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10223486

RESUMO

OBJECTIVES: To evaluate the relationship of DNA ploidy and cell proliferation (CP) with Gleason score (GS) and clinical outcome in prostate cancer. METHODS: Sixteen patients with benign prostatic hyperplasia (BPH) and 65 patients with prostate cancer classified by GS (four groups: 2 to 4, 5 to 6, 7, and 8 to 10) were studied. All patients with carcinoma underwent prostatectomy and were separated into prostate-specific antigen (PSA) failure and nonfailure groups (failure if PSA 0.1 ng/mL or more three times after surgery). Tumoral CP (Ki-67 inmunostaining and SG2M phase) and DNA ploidy were evaluated by computerized cytometry. RESULTS: BPH were diploid with low CP (8% SG2M cells or less). Carcinomas were either diploid with high CP (greater than 8% SG2M cells) or aneuploid. CP was significantly higher (P <0.001) in tumors with GS 7 or greater than in tumors with GS less than 7 (mean percent Ki-67 cells 18.3% versus 7.8%, respectively). PSA failure increased with GS (7.1% in GS 2 to 4, 21% in GS 5 to 6, 28.6% in GS 7, and 50% in GS 8 to 10), as well as with aneuploidy (18.5% in diploid tumors versus 72.7% in aneuploid tumors). Those experiencing PSA failure had significantly higher (P <0.001) CP than those not failing (mean percent Ki-67 cells 24% and mean percent SG2M 30.4% versus 8.7% and 13.5%, respectively). Cox regression analysis showed GS, DNA ploidy, Ki-67, and SG2M to each be univariately prognostic for time to PSA failure; however, Ki-67 and SG2M were more highly significant (P <0.0001 for both) than GS (P = 0.007) or DNA ploidy (P = 0.002). After adjusting for either SG2M or Ki-67 measures of CP, neither ploidy nor GS contained additional prognostic value. CONCLUSIONS: Tumor CP and DNA ploidy can be reliably determined in prostate cancer by computerized cytometry. On the basis of our preliminary results, CP correlates well with GS and predicts PSA failure better than DNA ploidy or GS.


Assuntos
Ploidias , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Idoso , Divisão Celular , Diagnóstico por Computador , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/sangue , Hiperplasia Prostática/genética , Hiperplasia Prostática/patologia , Neoplasias da Próstata/genética , Falha de Tratamento
12.
Development ; 126(12): 2799-811, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10331989

RESUMO

The lineage-restricted transcription factor GATA-1 is required for differentiation of erythroid and megakaryocytic cells. We have localized a 317 base pair cis-acting regulatory element, HS I, associated with a hematopoietic-specific DNase I hypersensitive site, which lies approx. 3.7 kilobases upstream of the murine hematopoietic-specific GATA-1 IE promoter. HS I directs high-level expression of reporter GATA-1/lacZ genes to primitive and definitive erythroid cells and megakaryocytes in transgenic mice. Comparative sequence analysis of HS I between human and mouse shows approx. 63% nucleotide identity with a more conserved core of 169 base pairs (86% identity). This core contains a GATA site separated by 10 base pairs from an E-box motif. The composite motif binds a multi-protein hematopoietic-specific transcription factor complex which includes GATA-1, SCL/tal-1, E2A, Lmo2 and Ldb-1. Point mutations of the GATA site abolishes HS I function, whereas mutation of the E-box motif still allows reporter gene expression in both lineages. Strict dependence of HS I activity on a GATA site implies that assembly of a protein complex containing a GATA-factor, presumably GATA-1 or GATA-2, is critical to activating or maintaining its function. Further dissection of the 317 base pair region demonstrates that, whereas all 317 base pairs are required for expression in megakaryocytes, only the 5' 62 base pairs are needed for erythroid-specific reporter expression. These findings demonstrate differential lineage requirements for expression within the HS I element.


Assuntos
Proteínas de Ligação a DNA/genética , Eritrócitos/fisiologia , Megacariócitos/fisiologia , Proteínas Proto-Oncogênicas , Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição/genética , Proteínas Adaptadoras de Transdução de Sinal , Animais , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Sítios de Ligação , Proteínas de Ligação a DNA/metabolismo , Desoxirribonuclease I/metabolismo , Fatores de Ligação de DNA Eritroide Específicos , Fator de Transcrição GATA1 , Regulação da Expressão Gênica , Genes Reporter , Humanos , Proteínas com Domínio LIM , Metaloproteínas/genética , Metaloproteínas/metabolismo , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Mutação , Filogenia , Proteínas/metabolismo , Deleção de Sequência , Homologia de Sequência do Ácido Nucleico , Proteína 1 de Leucemia Linfocítica Aguda de Células T , Fatores de Transcrição TCF , Proteína 1 Semelhante ao Fator 7 de Transcrição , Fatores de Transcrição/metabolismo
13.
Proc Natl Acad Sci U S A ; 96(3): 950-5, 1999 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-9927674

RESUMO

GATA factors are transcriptional regulatory proteins that play critical roles in the differentiation of multiple cell types in both vertebrates and invertebrates. Recent evidence suggests that the biological activities of both mammalian and Drosophila GATA factors are controlled in part by physical interaction with multitype zinc-finger proteins, Friend of GATA-1 (FOG) and U-shaped (Ush), respectively. Here we describe a new FOG-related polypeptide, designated FOG-2, that is likely to participate in differentiation mediated by GATA factors in several tissues. Expression of FOG-2 mRNA differs from that of FOG and is largely restricted to heart, neurons, and gonads in the adult. Somewhat broader expression is evident during mouse embryonic development. Similar to FOG and Ush, FOG-2 protein interacts specifically with the amino finger of GATA factors in the yeast two-hybrid system and in mammalian cells. Remarkably, though FOG-2 is quite divergent from FOG in its primary sequence, forced expression of FOG-2 rescues terminal erythroid maturation of FOG-/- hematopoietic cells. Thus, members of the FOG family of cofactors share highly specific association with GATA factors and are substantially interchangeable with respect to some aspects of function in vivo. The interaction of GATA and FOG family members constitutes an evolutionarily conserved paradigm for transcriptional control in differentiation and organogenesis.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Proteínas de Drosophila , Regulação da Expressão Gênica no Desenvolvimento , Sequência de Aminoácidos , Animais , Proteínas de Transporte/química , Proteínas de Transporte/genética , Clonagem Molecular , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Drosophila , Desenvolvimento Embrionário e Fetal , Eritropoese , Coração Fetal/metabolismo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia , Mamíferos , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Proteínas Nucleares/química , Proteínas Nucleares/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae , Alinhamento de Sequência , Fatores de Transcrição/química , Fatores de Transcrição/genética , Vertebrados , Dedos de Zinco
14.
Med Phys ; 25(9): 1655-66, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9775370

RESUMO

Current MRI nonuniformity correction techniques are reviewed and investigated. Many approaches are used to remedy this artifact, but it is not clear which method is the most appropriate in a given situation, as the applications have been with different MRI coils and different clinical applications. In this work four widely used nonuniformity correction techniques are investigated in order to assess the effect on tumor response measurements (change in tumor volume over time): a phantom correction method, an image smoothing technique, homomorphic filtering, and surface fitting approach. Six brain tumor cases with baseline and follow-up MRIs after treatment with varying degrees of difficulty of segmentation were analyzed without and with each of the nonuniformity corrections. Different methods give significantly different correction images, indicating that rf nonuniformity correction is not yet well understood. No improvement in tumor segmentation or in tumor growth/shrinkage assessment was achieved using any of the evaluated corrections.


Assuntos
Neoplasias Encefálicas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Fenômenos Biofísicos , Biofísica , Estudos de Avaliação como Assunto , Humanos , Processamento de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Imagens de Fantasmas
15.
Hum Pathol ; 29(6): 627-35, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9635685

RESUMO

CD44 is an adhesion molecule involved in cell-to-cell and cell-to-matrix interactions. This transmembrane glycoprotein exists in either standard or variant forms, originated by alternative splicing. One of the isoforms (CD44V6) has been shown, in some systems, to modify the metastatic potential of tumor cells. To investigate the role of this biomarker as possible prognostic antigen in colorectal cancer, we immunohistochemically analyzed the distribution of CD44V6 expression on formalin-fixed, paraffin-embedded tissues from resected colorectal cancers of 34 patients. The monoclonal antibody VFF7 against the amino acid sequence encoded by exon CD44V6 was applied using the avidin-biotin-peroxidase method. For each resected specimen, normal (N), adenomatous (AD), and carcinomatous (CA) colonic mucosa were tested. In 68% of the resected cases, these areas were present in the same slide, and in 76% of cases, nodal or liver metastases (MT) were available for evaluation. Adenomatous polyp biopsy specimens of 10 carcinoma-free patients were also tested. In selected cases, CD44V6 expression was also determined using the Western blot immunoprecipitation technique. CD44V6 immunoreactivity was detected in 100% of the ADs, and in 91% of CAs, but was mostly weak in only 38% of MTs (n=26). In 49% (n=35) of ADs, 11% (n=34) of CAs, and 4% of MTs (n=26), the stain was moderate to strong. CD44V6 immunoreactivity was predominantly membranous in ADs and cytoplasmic in MTs. In the CAs, both staining patterns were noted. Interestingly, the normal mucosa had a weak subnuclear localization of the stain. In the cases evaluated by Western blotting immunoprecipitation analysis, the level of CD44V6 protein expression was similar to that obtained by immunohistochemistry. No correlation was found with tumor type, stage, or patient survival. The predominant CD44V6 expression in ADs and CAs, but not in MTs, suggests that, in many cases, the expression of this adhesion molecule may be lost during the acquisition of migratory function by the tumor cells.


Assuntos
Adenocarcinoma/metabolismo , Adenoma/metabolismo , Antígenos de Neoplasias/metabolismo , Neoplasias Colorretais/metabolismo , Receptores de Hialuronatos/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Western Blotting , Colo/metabolismo , Colo/patologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida
16.
Ann Surg Oncol ; 4(3): 198-202, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9142379

RESUMO

BACKGROUND: The purpose of this study was to evaluate the tumor biology with respect to bilaterality and recurrence rates for bilateral infiltrating lobular (IL) breast carcinoma in comparison with other histological types. METHODS: A prospectively accrued data base containing 1,548 breast cancer cases as well as H. Lee Moffitt Cancer Center's cancer registry compiled during the same period were queried for specific features relating to bilaterality and recurrence. The 116 patients in this study had been treated at the Comprehensive Breast Cancer Clinic and had documented bilateral breast cancer (invasive on situ). RESULTS: Eighty-two of the patients (70.7%) had metachronous breast cancer, and 34 (29.3%) had synchronous cancer. Although median follow-up times were short, the risk of developing breast cancer in the contralateral breast after the diagnosis of cancer in the ipsilateral breast was estimated to be 0.7% per patient-year of follow-up. Recurrence rates for IL cancers were compared with those for invasive ductal (ID) and for ID + IL cancers. IL cancers recurred 8.1% of the time, whereas ID cancers recurred at a rate of 7.8%. Recurrences were equally divided between local and distant sites. CONCLUSIONS: Although IL cancers have demonstrated insidious behavior, their incidence of bilaterality is only slightly higher than other histologies and their rates of recurrence are low when properly evaluated and treated. The risk to the opposite breast also appears to be low. These data do not support the routine use of blind contralateral biopsy or prophylactic mastectomy.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Lobular/patologia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/terapia , Carcinoma in Situ/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/epidemiologia , Carcinoma Lobular/terapia , Feminino , Florida/epidemiologia , Humanos , Incidência , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/patologia , Prognóstico , Estudos Prospectivos , Recidiva , Estudos Retrospectivos , Fatores de Risco , Sensibilidade e Especificidade , Análise de Sobrevida
17.
J Fla Med Assoc ; 84(3): 161-5, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9143167

RESUMO

Contrary to the trend of early diagnosis observed in other parts of the world, in Florida melanoma is still being discovered in the more advanced stages. This is characterized by thicker lesions at diagnosis, which are hallmarked by bleeding, itching, ulceration, and increased vertical growth. In a study of 1,626 cutaneous melanoma patients at the H. Lee Moffitt Cancer Center in Florida, three prognostic factors, tumor thickness, Clark level, and presence of ulceration in the primary tumor, have remained relatively constant over an eight-year period (1987-1994). Despite the lack of change in tumor thickness in the last four years, mortality rate is decreasing, possibly due to more effective treatments. Regardless of these apparent improvements in mortality rates, definite progress must be made in the early detection of malignant melanoma through the initiation of statewide programs of lay public and professional education. In addition, it is proposed that the establishment of statewide screening programs of the Caucasian population with skin phenotypes 1 and 2 will also facilitate the early diagnosis of melanoma in the future, improve the outlook for these patients, and begin to address a major public health problem in the state of Florida.


Assuntos
Surtos de Doenças , Melanoma/epidemiologia , Neoplasias Cutâneas/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Educação Médica , Feminino , Florida/epidemiologia , Educação em Saúde , Humanos , Masculino , Programas de Rastreamento/métodos , Melanoma/mortalidade , Melanoma/patologia , Melanoma/prevenção & controle , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fenótipo , Prognóstico , Saúde Pública , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/prevenção & controle , Pigmentação da Pele/genética , Úlcera Cutânea/patologia , População Branca
18.
Br J Cancer ; 74(12): 1855-61, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8980382

RESUMO

Neuroblastoma is the most common extracranial solid tumour of childhood. Amplification of the proto-oncogene, N-myc, confers a poor prognosis in neuroblastoma, while hyperdiploidy is associated with a favourable outcome. Little is known about the contribution of tumour-suppressor genes to the development or progression of neuroblastoma. We examined allelic imbalance at the locus of the tumour-suppressor gene, APC (adenomatous polyposis coli), on chromosome 5q using a polymerase chain reaction (PCR)-based assay. Nine of 24 (37.5%) informative neuroblastoma tumours showed allelic imbalance (AI) at this locus. Clinical data concerning N-myc amplification and DNA content were correlated with these results in the same patients. Allelic imbalance was found only in tumours containing a single copy of the N-myc gene and exhibiting hyperdiploidy. All nine patients with AI of chromosome 5q were alive after a median follow-up period of 46 months, while 7 of 15 (47%) of those lacking AI at this locus had died (P = 0.018). Allelic imbalance at three additional loci on chromosome 5 was demonstrated in tumours that exhibited AI at the APC locus, suggesting that endoreduplication of chromosome 5 had occurred. Fluorescent in situ hybridisation (FISH) analysis of tumour tissue from one patient exhibiting AI demonstrated two, three, four or six copies of the APC gene per cell, consistent with this hypothesis. These data suggest that allelic imbalance of chromosome 5 is involved in at least a subset of neuroblastomas and influences survival in patients with neuroblastoma.


Assuntos
Alelos , Cromossomos Humanos Par 5/genética , Neoplasias do Sistema Nervoso/patologia , Neuroblastoma/patologia , DNA de Neoplasias/química , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor/genética , Humanos , Hibridização in Situ Fluorescente , Lactente , Neoplasias do Sistema Nervoso/genética , Neoplasias do Sistema Nervoso/mortalidade , Neuroblastoma/genética , Neuroblastoma/mortalidade , Reação em Cadeia da Polimerase/métodos , Proto-Oncogene Mas , Taxa de Sobrevida
19.
Arch Pathol Lab Med ; 120(9): 859-65, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9140292

RESUMO

BACKGROUND: Conventional criteria for ganglioneuroblastoma (GNB) do not require the presence of ganglioneuromatous component for pathologic diagnosis. This leads to inclusion of a mixed variety of neuroblastic tumors in the category of GNB. Therefore, GNB diagnosed by conventional criteria includes tumors showing more than 5% ganglion cells but no predominant ganglioneuromatous component, as well as tumors containing predominant ganglioneuromatous component. By previously described modified criteria, the former would be considered differentiating neuroblastoma (NB), and only the latter would be considered GNB. Data on Pediatric Oncology Group cases were analyzed to compare the prognostic subgroups of GNB diagnosed by conventional and modified criteria. The two prognostic subgroups (low risk and high risk) were defined on the basis of previously described prognostic differences between histologic grades of differentiating NBs and subtypes of GNB. METHODS: Pathologic data from cases of neuroblastic tumors registered on Pediatric Oncology Group NB protocols 8104 and 8441 were reviewed. The GNBs diagnosed by conventional and modified criteria were divided into low-risk and high-risk histology subgroups as follows: (1) GNB by conventional criteria: low-risk group, differentiating NB of histologic grades 1 and 2 and GNB of intermixed and borderline subtypes; high-risk group, differentiating NB of histologic grade 3 and GNB of nodular subtype; (2) GNB by modified criteria: low-risk group, GNB of intermixed and borderline subtypes; high-risk group, GNB of nodular subtype. RESULTS: The low- and high-risk subgroups of GNBs diagnosed by conventional (69 cases) and modified (36 cases) criteria showed statistically significant differences in survival (P = .03 and .01, respectively). However, from the histologic point of view, GNBs diagnosed by modified criteria form a more uniform morphologic group, which can be divided into low- and high-risk subgroups by a single set of morphologic criteria. In contrast, GNBs diagnosed by conventional criteria form a heterogeneous group, which requires two sets of criteria (ie, histologic grade and subtypes of GNB) for its classification into low- and high-risk subgroups. CONCLUSIONS: The modified criteria for GNB define a morphologically uniform group of neuroblastic tumors to which a single set of prognostic criteria can be applied. It is recommended that the term GNB should be used both clinically and pathologically to designate a distinctive subgroup of neuroblastic tumors, in contrast to the current use, which designates both NB and GNB.


Assuntos
Ganglioneuroblastoma/patologia , Ganglioneuroblastoma/classificação , Ganglioneuroblastoma/diagnóstico , Humanos , Prognóstico , Fatores de Risco
20.
Lung Cancer ; 14(2-3): 239-51, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8794407

RESUMO

Monitoring respiratory epithelial biology may reveal individuals with incipient lung cancer. The expression of neuroendocrine (NE) markers in pulmonary epithelium is thought to be central to lung development, repair of injury and may contribute to carcinogenesis. In this study, we evaluate several candidate NE markers to determine the feasibility of prospective analysis of clinical specimens. The potential NE markers include the enzyme L-DOPA decarboxylase (DDC), the neuropeptide gastrin releasing peptide (GRP), and peptidyl-glycine alpha-amidating monooxygenase (PAM), the bifunctional enzyme responsible for the final bioactivation step of many neuropeptides. A comparison of PAM activity and DDC levels in 30 lung cancer cell lines indicated that peptide amidating activity may be an indicator of NE status. Bronchoalveolar lavage (BAL) fluid from subjects at risk of developing second primary lung cancer and from volunteers was obtained. The activity of the first PAM enzyme, peptidylglycine alpha-hydroxylating monooxygenase (PHM), ranged from not detectable to 507 pmol/h/mg protein in 57 specimens. The second PAM enzyme, peptidylamidoglycolate lyase (PAL), ranged from not detectable to 414 pmol/h/mg protein in 56 specimens. Using cluster analysis by the average linkage method, a group of enzyme values with PHM greater than 230 pmol/h/mg protein was determined. Long-term follow-up of these patients for new second primary lung cancers may help to determine the potential predictive value of PAM detected in the BAL fluid.


Assuntos
Biomarcadores Tumorais/metabolismo , Líquido da Lavagem Broncoalveolar/química , Neoplasias Pulmonares/metabolismo , Proteínas de Neoplasias/metabolismo , Biomarcadores Tumorais/análise , Substâncias de Crescimento/análise , Substâncias de Crescimento/metabolismo , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/enzimologia , Proteínas de Neoplasias/análise , Células Tumorais Cultivadas
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