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1.
Acta Cytol ; 45(6): 965-72, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11726126

RESUMO

OBJECTIVE: To use MIB-1 antibody to assess proliferative activity in fine needle aspiration (FNA) samples of invasive breast carcinoma and compare these results to multiple other measures of proliferative activity. STUDY DESIGN: FNA slides from 62 patients with invasive breast carcinoma were subjected to staining with MIB-1. Quantitative MIB-1 values were compared to image analytic proliferative fractions (IPF) obtained from the same FNAs. MIB-1 values were also compared to flow cytometric S-phase fractions (SPF) and S + G2/M-phase fractions (FPF) and to histologic assessment of mitotic count (MC) in resected tumors. RESULTS: MIB-1 values, IPF, SPF, FPF and MC were suitable for evaluation in 55, 53, 50, 50 and 56 cases, respectively. MIB-1 values showed good correlation with IPF in FNAs (correlation coefficient = .57, P <.00001). MIB-1 values also showed correlation with SPF (correlation coefficient =.447, P = .003), FPF (correlation coefficient = .325, P = .023) and MC (correlation coefficient = .402, P = .01) in resected tumors. CONCLUSION: This study supports the use of MIB-1 values obtained from FNA samples for assessment of proliferative activity in invasive breast carcinoma, based on correlation of these values with multiple other parameters of proliferative activity. Assessment of these values can play a role in predicting prognosis and in selecting patients with invasive carcinoma of the breast for preoperative or adjuvant chemotherapy.


Assuntos
Adenocarcinoma/patologia , Neoplasias da Mama/patologia , Proteínas Nucleares/metabolismo , Adenocarcinoma/química , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Antígenos Nucleares , Biópsia por Agulha , Neoplasias da Mama/química , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Ciclo Celular , Divisão Celular , DNA de Neoplasias/análise , Feminino , Citometria de Fluxo , Humanos , Citometria por Imagem , Imuno-Histoquímica , Antígeno Ki-67 , Invasividade Neoplásica/patologia , Proteínas Nucleares/análise , Ploidias , Reprodutibilidade dos Testes
3.
Hum Pathol ; 32(1): 113-8, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11172304

RESUMO

The aim of this work was to determine the extent of estrogen receptor beta (ER-beta) expression in invasive breast cancer (BrCA) and whether ER-beta expression is correlated with response to adjuvant hormonal therapy with tamoxifen (AHTT). Immunohistochemical staining (IHC) for estrogen receptor alpha (ER-alpha) and ER-beta was performed on sections of formalin-fixed and paraffin-embedded tissue from 47 unselected invasive breast carcinomas (BrCA). IHC for ER-beta was also performed on sections of BrCA from 118 women who were treated with mastectomy and AHTT. Survival analysis was performed using the Kaplan-Meier method and the log-rank test. Of the 47 unselected BrCA, 17 (36%) were negative for ER-alpha and of these, 8 (47% of ER-alpha negative cases and 17% of all 47 patients) were ER-beta positive. Five of the 8 ER-alpha negative and ER-beta positive cases were positive for ER biochemically. There was no correlation between ER-beta positivity and overall survival in the unselected group. By contrast, in the group of women treated with AHTT, expression of ER-beta in more than 10% of cancer cells was associated with better survival (P = .0077), even in women with node-negative BrCA (P = .0069). In conclusion, our results show that a significant number of women with BrCA are positive for ER-beta only, and may be determined to be ER-negative when currently available IHC is used. ER-beta status is a significant predictor of response to AHTT in women with BrCA. Larger studies with multivariate analysis are needed to confirm these findings.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Receptores de Estrogênio/biossíntese , Western Blotting , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Análise de Sobrevida
4.
Cancer Res ; 61(1): 261-9, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11196172

RESUMO

The transcription factor, CCAAT/enhancer binding protein beta (C/EBPbeta), regulates the expression of genes involved in proliferation and terminal differentiation. Dimerization of the dominant-negative C/EBPbeta-liver-enriched inhibitory protein (LIP) isoform with the C/EBPbeta-liver-enriched activating protein (LAP) isoform inhibits the transcriptional activation of genes involved in differentiation. Consequently, an increase in LIP levels may inhibit terminal differentiation and lead to proliferation. C/EBPbeta-LIP and LAP are crucial for mammary gland development (G. W. Robinson et al., Genes Dev., 12: 1907-1916, 1998; T. N. Seagroves et al., Genes Dev., 12: 1917-1928, 1998) and are also overexpressed in breast cancer (B. Raught et al., Cancer Res., 56: 4382-4386. 1996; C. A. Zahnow et al., J. Natl. Cancer Inst., 89: 1887-1891, 1997); however, little is known about how these isoforms differentially regulate cell cycle progression. To address this question, C/EBPbeta-LIP was overexpressed in both the mammary glands of transgenic mice and in cultured TM3 mammary epithelial cells. Here we report that the involuted mammary glands from transgenic mice overexpressing C/EBPbeta-LIP contain both focal and diffuse alveolar hyperplasia and, less frequently, contain mammary intraepithelial neoplasias (high grade) and invasive and noninvasive carcinomas. Likewise, cultured TM3 cells, stably expressing C/EBPbeta-LIP, showed an increase in proliferation and foci formation attributable to a reentry into S-phase during cellular confluence. These results demonstrate that C/EBPbeta-LIP can induce epithelial proliferation and the formation of mammary hyperplasias and suggest that a C/EBPbeta-LIP-initiated growth cascade may be susceptible to additional oncogenic hits, which could result in the initiation and progression of neoplasia.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/fisiologia , Glândulas Mamárias Animais/citologia , Animais , Proteína beta Intensificadora de Ligação a CCAAT/biossíntese , Proteína beta Intensificadora de Ligação a CCAAT/genética , Divisão Celular/fisiologia , Linhagem Celular , Transformação Celular Neoplásica/patologia , Transplante de Células , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Hiperplasia/metabolismo , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Ratos , Transfecção
5.
Am J Clin Pathol ; 115(1): 18-31, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11190804

RESUMO

This study focused on 19 patients with renal lymphoma (RL) from whom 20 initial (1 patient with fine-needle aspiration [FNA] specimens of masses in both kidneys) and 1 repeated FNA specimen were obtained. Of the 19 patients, 10 had secondary RL, 8 primary RL, and 1 transplant RL. The FNA samples were studied by smears (all cases), tissues (11), phenotyping by immunostaining (13) or flow cytometry (4), and gene rearrangement (3). The final diagnoses included 1 T-cell lymphoma and 18 B-cell lymphomas. Of the 20 original specimens, 14 were reported as positive for lymphoma, 3 suggestive of lymphoma, 1 positive for transitional cell carcinoma, and 2 unsatisfactory. The follow-up specimen showed reactive changes. Tissue correlation, available in 11 cases, confirmed a positive cytodiagnosis (7), provided a final diagnosis in the cytologically inconclusive cases (3), or revised the misdiagnosis of transitional cell carcinoma from smears (1). The phenotyping elucidated the B vs T lineage of the lymphoma in all tested cases, confirmed the positive cytodiagnosis in 10 cases, confirmed the reactive cytodiagnosis in 1 case, and helped achieve a conclusive diagnosis in 2 cases suggestive of lymphoma. Gene rearrangement studies showed light chain restriction in the 2 tested cases. FNA has an essential role in treatment planning for RL. Although FNA usually is diagnostically conclusive, a high index of suspicion and awareness of atypical or misleading cytomorphologic features are important for a correct interpretation, especially for primary RL. Ancillary testing is essential for the diagnosis in problematic cases and lays the foundation for the differential diagnosis.


Assuntos
Biópsia por Agulha , Neoplasias Renais/patologia , Linfoma de Células B/patologia , Linfoma de Células T/patologia , Adulto , Idoso , Criança , Feminino , Rearranjo Gênico , Humanos , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/genética , Linfoma de Células B/diagnóstico por imagem , Linfoma de Células B/genética , Linfoma de Células T/diagnóstico por imagem , Linfoma de Células T/genética , Masculino , Pessoa de Meia-Idade , Fenótipo , Tomografia Computadorizada por Raios X
6.
Am J Pathol ; 157(6): 2151-9, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11106587

RESUMO

Breast cancer is the most frequent tumor type among women in the United States and in individuals with Li-Fraumeni syndrome. The p53 tumor suppressor gene is altered in a large proportion of both spontaneous breast malignancies and Li-Fraumeni breast cancers. This suggests that loss of p53 can accelerate breast tumorigenesis, yet p53-deficient mice rarely develop mammary tumors. To evaluate the effect of p53 loss on mammary tumor formation, the p53(null) allele was back-crossed onto the BALB/c genetic background. Median survival was 15.4 weeks for BALB/c-p53(-/-) mice compared to 54 weeks for BALB/c-p53(+/-) mice. Sarcomas and lymphomas were the most frequent tumor types in BALB/c-p53(-/-) mice, whereas 55% of the female BALB/c-p53(+/-) mice developed mammary carcinomas. The mammary tumors were highly aneuploid, frequently lost the remaining wild-type p53 allele, but rarely lost BRCA1. Although mammary tumors were rarely detected in BALB/c-p53(-/-) female mice, when glands from BALB/c-p53(-/-) mice were transplanted into wild-type BALB/c hosts, 75% developed mammary tumors. The high rate of mammary tumor development in the BALB/c background, but not C57Bl/6 or 129/Sv, suggests a genetic predisposition toward mammary tumorigenesis. Therefore, the BALB/c-p53(+/-) mice provide a unique model for the study of breast cancer in Li-Fraumeni syndrome. These results demonstrate the critical role that the p53 tumor suppressor gene plays in preventing tumorigenesis in the mammary gland.


Assuntos
Heterozigoto , Síndrome de Li-Fraumeni/genética , Neoplasias Mamárias Animais/genética , Camundongos Endogâmicos BALB C/genética , Proteína Supressora de Tumor p53/genética , Animais , Modelos Animais de Doenças , Feminino , Deleção de Genes , Genes BRCA1/genética , Incidência , Masculino , Neoplasias Mamárias Animais/epidemiologia , Neoplasias Mamárias Animais/patologia , Camundongos , Camundongos Endogâmicos , Fenótipo , Análise de Sobrevida , Proteína Supressora de Tumor p53/deficiência
7.
Urology ; 56(5): 735-40, 2000 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11068290

RESUMO

OBJECTIVES: To determine whether molecular and histopathologic tumor features can predict disease progression in Stage T1 transitional cell carcinoma of the bladder. METHODS: Tumor specimens from 43 patients were analyzed with respect to grade, presence of carcinoma in situ, invasion deep or superficial to the lamina propria's muscularis mucosa, p53 expression using DO-7 and PAb1801 antibodies, age, and sex. Flow cytometry was performed on 30 patients from whom there was adequate paraffin-embedded tissue to assess DNA ploidy. Seven patients underwent immediate cystectomy as primary treatment and 36 patients retained their bladders and were at risk of recurrence and progression. RESULTS: The median follow-up was 79 months. Disease recurred in 17 patients (47.2%) and progressed in 6 (16.7%). Only 3 patients (7.0%) died of bladder cancer. None of the parameters investigated was statistically significant in predicting recurrence, progression, or survival. Only carcinoma in situ approached statistical significance (P = 0.0593) as a predictor of progression. Early cystectomy did not have a significant effect on cancer-specific survival (P = 0.3603). The concordance rate between the two p53 antibodies was 88% (P <0.0001). CONCLUSIONS: Deep invasion of the lamina propria, p53 positive immunohistochemistry, high grade, and aneuploidy were not significant adverse prognostic factors for either disease progression or survival. Carcinoma in situ associated with Stage T1 transitional cell carcinoma may represent a biologically more aggressive cancer requiring early definitive therapy, but this hypothesis should be evaluated in prospective clinical studies.


Assuntos
Carcinoma in Situ/patologia , Carcinoma de Células de Transição/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias da Bexiga Urinária/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , DNA de Neoplasias/análise , Progressão da Doença , Feminino , Citometria de Fluxo , Seguimentos , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Ploidias , Prognóstico , Proteína Supressora de Tumor p53/análise
8.
Oncogene ; 19(7): 889-98, 2000 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-10702797

RESUMO

Mammary tumorigenesis was analysed in transgenic mice which overexpress des(1-3)hIGF-I (WAP-DES) and/or a mutant form of p53 (p53172R-H). Nonlactating, multiparous WAP-DES mice exhibited hyperplastic lesions termed mammary interepithelial neoplasia (MIN) which constitutively expressed WAP-DES. By 23 months of age, 53% of the WAP-DES mice developed mammary adenocarcinomas. A 75% reduction in both apoptosis and proliferation was observed in the normal mammary glands of WAP-DES mice. Mammary tumor incidence in WAP-DES/p53 bitransgenic mice was similar to that of WAP-DES and 2 - 3-fold greater than that of nontransgenic and p53172R-H females. Tumor latency, however, was reduced by 8 months in bitransgenic mice as compared to mice of the other three genotypes. Aneuploidy was frequently observed in tumors from bitransgenic and p53172R-H mice, but not from mice expressing only the WAP-DES transgene. Expression of IGFBP3 was elevated in tumors from WAP-DES, but not bitransgenic mice, indicating an alteration in the p53/IGF-I axis. These studies indicate that overexpression of des(1-3)hIGF-I increases the frequency of MIN and stochastic mammary tumors and that the appearance of tumors displaying genomic instability is accelerated by mutant p53172R-H. Oncogene (2000) 19, 889 - 898.


Assuntos
Fator de Crescimento Insulin-Like I/metabolismo , Neoplasias Mamárias Experimentais/etiologia , Neoplasias Mamárias Experimentais/genética , Mutação/genética , Fragmentos de Peptídeos/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/genética , Replicação do DNA/genética , Sinergismo Farmacológico , Feminino , Masculino , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Transgênicos
9.
Oncogene ; 19(8): 1052-8, 2000 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-10713689

RESUMO

Although alterations in the p53 tumor suppressor gene are detected frequently in human breast cancers, mammary tumors are observed infrequently in p53(null) mice. This has led to the suggestion that absence of p53 alone is not sufficient for induction of mammary tumors. However, early death of p53(null) mice from thymic lymphomas may obscure tumor phenotypes that would develop later. Therefore, p53(null) mammary epithelium was transplanted into cleared mammary fat pads of wild type p53 BALB/c hosts to allow long-term analysis of mammary tumor phenotypes. Five treatments were compared for their effects on tumor incidence in hosts bearing transplants of p53(null) and p53wt mammary epithelium. The treatment groups were: (1) untreated; (2) continuous hormone stimulation with pituitary isografts; (3) multiple pregnancies; (4) DMBA alone; and (5) DMBA+pituitary isografts. The tumor incidences in p53(null) vs p53wt mammary transplants for each treatment group were 62% vs 0%, 100% vs 0%, 68% vs 0%, 60% vs 4% and 91% vs 14%, respectively. The mammary tumors that developed in the p53(null) mammary epithelium were all adenocarcinomas and were frequently aneuploid. These data demonstrate that the absence of p53 is sufficient to cause development of mammary tumors and that hormonal stimulation enhances the tumorigenicity of p53(null) mammary epithelium to a greater extent than DMBA exposure alone. This model provides an in situ approach to examine the molecular basis for the role of p53 in the regulation of mammary tumorigenesis.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/patologia , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Proteína Supressora de Tumor p53/genética , 9,10-Dimetil-1,2-benzantraceno , Adenocarcinoma/induzido quimicamente , Adenocarcinoma/epidemiologia , Aneuploidia , Animais , Carcinógenos , Modelos Animais de Doenças , Células Epiteliais/patologia , Células Epiteliais/transplante , Feminino , Genes Supressores de Tumor , Incidência , Neoplasias Mamárias Experimentais/epidemiologia , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Hipófise/metabolismo , Gravidez
10.
Oncogene ; 19(8): 1010-9, 2000 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-10713684

RESUMO

Understanding the process of carcinogenesis is key to developing therapies which might interrupt or reverse tumor onset and progression. Cell growth and death signals are dependent not only upon molecular mechanisms within a cell but also upon external stimuli such as hormones, cell - cell signaling, and extracellular matrix. Mouse models can be used to dissect these complex processes, to identify key signaling pathways operating at different stages of tumorigenesis, and to test the strength of specific interventions. In the WAP-TAg mouse model, carcinogenesis is initiated by expression of the Simian Virus 40 T antigen (TAg). TAg expression is triggered by hormonal stimulation, either during estrus or pregnancy. Breast adenocarcinomas (ranging from well to poorly differentiated) develop in 100% of the female mice by approximately 8 - 9 months of age. Three distinct stages of tumorigenesis are easily identified: an initial proliferation, hyperplasia, and adenocarcinoma. The mean time to first palpable tumor in mice which undergo at least one pregnancy is 6 months. The tumorigenic process is marked by a competition between proliferation and apoptosis and is characterized by cellular acquisition of genetic mutations and increased stromal fibrosis. Protein levels of cell cycle control genes cyclin D1, cdk2, and E2F-1 are increased in these adenocarcinomas. c-Fos protein levels are slightly increased in these cancers, while c-Jun levels do not change. Hormonal exposure alters progression. Estrogen plays a role during the early stages of oncogenesis although the growth of the resulting adenocarcinomas is estrogen-independent. Transient hormonal stimulation by glucocorticoids that temporarily increases the rate of cell proliferation results in tetraploidy, premature appearance of irreversible hyperplasia, and early tumor development. Tumor appearance also can be accelerated through over expression of the cell survival protein, Bcl-2. Bcl-2 over expression not only reduces apoptosis during the initial proliferative process but also decreases the total rate of cell proliferation. This block in cell proliferation is lost selectively as the cells transition to adenocarcinoma. The WAP-TAg model can be utilized to investigate how the basic processes of cell proliferation, apoptosis, DNA mutation, and DNA repair are modified by external and internal signals during mammary oncogenesis.


Assuntos
Antígenos Transformantes de Poliomavirus/genética , Hormônios/metabolismo , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Mutação , Proteínas Proto-Oncogênicas c-bcl-2/genética , Animais , Mama/crescimento & desenvolvimento , Mama/metabolismo , Divisão Celular/genética , Sobrevivência Celular/genética , Modelos Animais de Doenças , Estrogênios/fisiologia , Feminino , Regulação Neoplásica da Expressão Gênica , Glucocorticoides/metabolismo , Glucocorticoides/farmacologia , Humanos , Hiperplasia/induzido quimicamente , Glândulas Mamárias Animais/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Camundongos Transgênicos , Mitose , Gravidez , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2
11.
Oncogene ; 18(47): 6589-96, 1999 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-10597263

RESUMO

Bcl-2 is an anti-apoptotic and anti-proliferative protein over-expressed in several different human cancers including breast. Gain of Bcl-2 function in mammary epithelial cells was superimposed on the WAP-TAg transgenic mouse model of breast cancer progression to determine its effect on epithelial cell survival and proliferation at three key stages in oncogenesis: the initial proliferative process, hyperplasia, and cancer. During the initial proliferative process, Bcl-2 strongly inhibited both apoptosis and mitotic activity. However as tumorigenesis progressed to hyperplasia and adenocarcinoma, the inhibitory effects on mitotic activity were lost. In contrast, anti-apoptotic activity persisted in both hyperplasias and adenocarcinomas. These results demonstrate that the inhibitory effect of Bcl-2 on epithelial cell proliferation and apoptosis can separate during cancer progression. In this model, retention of anti-apoptotic activity with loss of anti-proliferative action resulted in earlier tumor presentation.


Assuntos
Adenocarcinoma/patologia , Neoplasias Mamárias Experimentais/patologia , Mitose/genética , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Adenocarcinoma/genética , Animais , Modelos Animais de Doenças , Humanos , Neoplasias Mamárias Experimentais/genética , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-bcl-2/genética
12.
J Cell Physiol ; 180(3): 431-8, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10430183

RESUMO

Previous studies have shown that rapid cell proliferation is associated with elevated glucose consumption. However, those studies did not establish whether glucose is required for prostate cancer cell proliferation or define the molecular mechanisms by which glucose regulates cell division. We addressed these issues by studying two metastatic human prostate cancer cell lines: DU145, which is androgen independent and highly proliferative; and LNCaP, which is androgen dependent and relatively slow growing. We found that proliferation of DU145 cells was significantly inhibited by reduction of glucose in the medium to 0.5 g/L, which is half the physiologic concentration, whereas LNCaP cells grew at control rates even in the presence of only 0.05 g/L glucose. Glucose deprivation of DU145 cells caused a 90% reduction in DNA synthesis; a 10-20-fold reduction in cyclins D and E and CDK4 levels; and cell cycle arrest in G0-G1. However, glucose deprivation did not cause global inhibition of protein synthesis, since mutant p53 levels increased in glucose-deprived DU145 cells. This observed increase in mutant p53 levels was not associated with a rise in p21 levels. Glucose deprivation of DU145 cells also led to apparent dephosphorylation of mutant retinoblastoma (RB) protein. We conclude that: 1) high levels of glucose consumption are required for rapid proliferation of androgen-independent prostate cancer cells, 2) glucose may not be required for slow growth of androgen-dependent prostate cancer cells, and 3) glucose promotes passage of cells through early G1 by increasing the expression of several key cell cycle regulatory proteins that normally inhibit RB function.


Assuntos
Glucose/fisiologia , Neoplasias da Próstata/patologia , Trifosfato de Adenosina/metabolismo , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/fisiologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Ciclina D , Ciclinas/metabolismo , Glucose/deficiência , Glucose/farmacologia , Humanos , Masculino , Neoplasias da Próstata/metabolismo , Proteína do Retinoblastoma/metabolismo , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/metabolismo
13.
Mol Carcinog ; 24(3): 197-208, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10204804

RESUMO

A number of transgenic animal model systems have addressed the mechanistic role of p53 loss in tumor progression. However, many of these tumor models have analyzed p53 function in the context of other transgenes expressing activated oncogenes or defective tumor suppressor genes generated by gene targeting. To examine the role of p53 loss independent of other exogenous oncogenic influences, we analyzed some of the biological aspects of tumor formation and progression in p53-knockout mice containing a null germline p53 allele. We analyzed tumors from p53-/-, p53+/-, and p53+/+ littermates. Some of the p53+/- tumors had lost the remaining p53 allele (p53+/- loss of heterozygosity), whereas others retained the allele (p53+/-). In this report, we show that loss or absence of p53 conferred a tumor growth advantage by increasing the rate of cellular proliferation in a p53 dosage-dependent manner. The apoptotic levels in tumor tissue were found to be modest and not significantly dependent on p53 status. These results contrast with those from some other p53-deficient tumor models, in which p53 loss was associated with more rapid tumor progression through abrogated apoptosis. Finally, as p53 has been shown to regulate certain angiogenic factors, we examined the levels of angiogenesis in p53-containing and p53-deficient tumors. We found no p53-dependent differences in the levels of tumor angiogenesis measured by intratumoral microvessel density.


Assuntos
Genes p53 , Neoplasias Experimentais/genética , Alelos , Animais , Apoptose/genética , Divisão Celular , DNA de Neoplasias/análise , Predisposição Genética para Doença , Genótipo , Perda de Heterozigosidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Índice Mitótico , Neoplasias Experimentais/patologia , Neovascularização Patológica/genética , Deleção de Sequência , Fator de von Willebrand/análise
14.
Urology ; 54(3): 561, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10754141

RESUMO

Extension of renal cell carcinoma (RCC) along venous drainage pathways is a well-recognized entity. All previously reported cases of inferior vena cava (IVC) involvement by RCC have been with tumor thrombus in the suprarenal IVC. We report a 45-year-old man who had RCC arising from the lower pole of the right kidney with a tumor thrombus totally occluding the infrarenal IVC. The patient underwent radical nephrectomy with successful ligation and resection of the infrarenal IVC.


Assuntos
Carcinoma de Células Renais/irrigação sanguínea , Neoplasias Renais/irrigação sanguínea , Células Neoplásicas Circulantes , Veia Cava Inferior , Carcinoma de Células Renais/complicações , Humanos , Neoplasias Renais/complicações , Masculino , Pessoa de Meia-Idade
15.
Oncogene ; 16(8): 997-1007, 1998 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-9519874

RESUMO

Missense mutations in the p53 tumor suppressor occur frequently in human breast cancer and influence both the prognosis and response to chemotherapy. Amino acid 175 (equivalent to murine 172) is the second most common site of missense mutations in p53 in human breast cancer. Over 95% of these mutations are arginine-to-histidine (R-H) substitutions resulting in a gain-of-function, and not merely a dominant-negative phenotype. Transgenic mice expressing a p53 172(R-H) construct targeted to the mammary gland by means of a whey acidic protein (WAP) promoter were characterized as a model system in order to determine the specific effects of this mutation on mammary tumorigenesis. Although transgene expression alone had no apparent effect on normal mammary development, transgenic mice treated with the chemical carcinogen dimethylbenz(a)anthracene developed tumors with much shorter latency than did control littermates and had a greater tumor burden. Tumors arising in transgenic mice did not exhibit either decreased apoptosis or increased cell proliferation relative to tumors arising in nontransgenic littermates, but did display increased genomic instability. Large pleiomorphic nuclei were visible in many tumors from transgenic mice, and DNA flow analysis confirmed the presence of significant aneuploid cell populations. Since these transgenic mice develop very few spontaneous tumors, while accelerating carcinogen-and oncogene-mediated tumorigenesis, this mouse model will, therefore, be useful in the investigation of early events in mammary tumorigenesis. It may also be used as a preclinical model to test newly developed chemotherapeutic strategies.


Assuntos
Neoplasias Mamárias Experimentais/genética , 9,10-Dimetil-1,2-benzantraceno , Animais , Carcinógenos , Cocarcinogênese , Modelos Animais de Doenças , Suscetibilidade a Doenças , Feminino , Expressão Gênica , Genes p53 , Genes ras , Glândulas Mamárias Animais/crescimento & desenvolvimento , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/fisiologia , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Camundongos Transgênicos , Mutação , Transgenes , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/biossíntese
16.
J Natl Cancer Inst ; 89(24): 1887-91, 1997 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-9414177

RESUMO

BACKGROUND: When cells fail to maintain a balance between proliferation, terminal differentiation, and programmed cell death, cancer often results. The CCAAT/enhancer-binding protein (C/EBP) family of transcription factors regulates many genes involved in the processes of proliferation and terminal differentiation. The messenger RNA for C/EBPbeta is translated into two major isoforms, LAP (liver-enriched activating protein) and LIP (liver-enriched inhibitory protein). LIP levels appear to be elevated in mouse mammary tumors but not in hyperplastic mammary tissues. We tested whether LIP expression is elevated in human breast cancer and whether elevated expression is associated with biologic predictors of the aggressiveness of the disease. METHODS: Homogenates of infiltrating ductal carcinoma specimens from 39 women were analyzed for C/EBPbeta protein content by western blot analysis, and the ratio of LAP to LIP in specimens containing high levels of LIP (i.e., levels approximately 15 times higher than those in tumor specimens that express little or no LIP) was also determined. Nonparametric statistical analyses were performed. RESULTS: LIP was present at high levels in nine of 39 specimens of infiltrating ductal carcinoma. Eight of the nine specimens of infiltrating ductal carcinoma that contained high levels of LIP were negative for estrogen receptor and progesterone receptor (ER-/PR-); all nine tumors were aneuploid and poorly differentiated, and eight of nine were highly proliferative. Of the tumors that contained LIP at low or nondetectable levels, six of 30 were ER-/PR-, 17 of 29 were aneuploid, eight of 27 were highly proliferative, and 11 of 30 were poorly differentiated. IMPLICATION: LIP expression should be evaluated further as a prognostic marker for patients with breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Proteínas de Ligação a DNA/biossíntese , Regulação Neoplásica da Expressão Gênica , Proteínas Nucleares/biossíntese , Proteínas Repressoras/biossíntese , Fatores de Transcrição/biossíntese , Western Blotting , Neoplasias da Mama/patologia , Proteína beta Intensificadora de Ligação a CCAAT , Proteínas Estimuladoras de Ligação a CCAAT , Carcinoma Ductal de Mama/patologia , Divisão Celular , Feminino , Humanos , Imuno-Histoquímica , Ploidias , Valor Preditivo dos Testes , Prognóstico , Receptores de Estrogênio , Receptores de Progesterona , Fatores de Risco , Estatísticas não Paramétricas , Regulação para Cima
17.
Cell Growth Differ ; 8(8): 829-38, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9269892

RESUMO

Loss or mutation of p53 may have multiple biological and genetic effects that result in accelerated tumor progression. Loss of p53 in some tumors has been correlated with a marked decrease in tumor cell apoptosis. p53 loss may also accelerate tumor growth through an increase in cell proliferation rates. To examine the effects of p53 loss on tumor progression in a controlled experimental context, we previously crossed p53-deficient mice to mammary tumor-susceptible Wnt-1 transgenic (TG) mice. The resulting female Wnt-1 TG offspring of this cross all developed mammary tumors, regardless of p53 status (p53+/+, p53+/-, or p53-/-). However, female p53-/- Wnt-1 TG mice developed tumors much sooner than their p53+/+ counterparts. In this report, we demonstrate that the average growth rates of tumors missing (p53-/-) or losing p53 (p53+/- with loss of heterozygosity) are accelerated compared to tumors with both wild-type p53 alleles (p53+/+). This accelerated growth rate appears to be due primarily to increases in rates of tumor cell proliferation. Tumor cell apoptotic levels were modest and were not measurably different in the presence or absence of wild-type p53. These results differ substantially from other mouse tumor models in which p53 loss was closely correlated with accelerated growth rates through attenuated apoptosis. Thus, the mechanisms by which p53 loss influences tumor progression may differ, depending on the tissue type and/or the oncogenic pathways involved.


Assuntos
Apoptose/fisiologia , Genes p53/fisiologia , Neoplasias Mamárias Experimentais/patologia , Proteínas de Peixe-Zebra , Animais , Divisão Celular , Cruzamentos Genéticos , DNA de Neoplasias/análise , Feminino , Hiperplasia , Glândulas Mamárias Animais/patologia , Camundongos , Camundongos Transgênicos , Mitose , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Wnt , Proteína Wnt1
18.
Clin Cancer Res ; 3(4): 601-4, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9815726

RESUMO

Histological grade (HG), as modified by Elston and Ellis (Histopathology, 19: 403-410, 1991), was shown to be a significant prognostic indicator in a large group of women with invasive breast cancer, who had node-negative as well as node-positive tumors and included special types of breast cancer. The aim of this study was to determine the utility of HG as a prognostic indicator in node-negative invasive breast cancer, no special type (NN-BCA-NST), which represents the majority of cases seen in clinical practice. One hundred eighty-two women with NN-BCA-NST and who had 28-106 months follow-up (mean, 73 months; median, 71 months) were entered in the study. Bilateral and multifocal cancers, and cancers with distant metastases, were excluded. Nuclear grade (NG), tubule formation (TF), mitotic index (MI), and HG were determined and scored as described by Elston and Ellis (Histopathology, 19: 403-410, 1991). Survival analysis was performed by the Kaplan-Meier method and the log-rank test. Regression analysis was used to determine the relationship between NG, TF, and MI. There was significant correlation between NG and MI (R = 0.667, P < 0.0001) and between TF and MI (R = 0.416, P < 0.0001). NG, TF, MI, and HG did not have significant prognostic value (P = 0.3771, P = 0.7972, P = 0.2953, and P = 0.7946, respectively). HG was of no significant prognostic value even after women who received adjuvant therapy were excluded from the analysis (P = 0.3917). Our data show that the HG is not a reliable prognostic indicator in NN-BCA-NST.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Fatores Etários , Neoplasias da Mama/mortalidade , Neoplasias da Mama/cirurgia , Terapia Combinada , Feminino , Seguimentos , Humanos , Linfonodos/patologia , Metástase Linfática , Pessoa de Meia-Idade , Índice Mitótico , Invasividade Neoplásica , Valor Preditivo dos Testes , Prognóstico , Receptores de Estrogênio/análise , Análise de Sobrevida , Fatores de Tempo
19.
Anticancer Res ; 17(2B): 1383-90, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9137503

RESUMO

Published results using prognostic markers in breast cancer have been very confusing to oncologists, surgeons, and pathologists alike. As a result, there is a wide variation in opinion among oncologists about the utility of these markers in clinical practice. This study was undertaken to determine the utility of stratified multivariate survival analysis in integrating the commonly used prognostic factors into a user-friendly prognostic scheme, and its implication for treatment decision making. 300 women with invasive ductal carcinoma of the breast who were followed-up for 28-112 months (median 72 months) were entered in the study. Patients with distant metastases, those with bilateral or multifocal tumors, and special types of carcinoma were excluded. Variables included in the stratified multivariate survival analysis were estrogen receptor (ER) status, tumor size, nodal status, histological grade, number of mitotic figures per ten high power fields (MF/10HPF), and type of initial therapy. Data was subjected to Kaplan-Meier survival analysis and the log rank test for statistical significance at different steps of the analysis. Cut-off values for ER that produced a significant difference in survival varied from 9 fmol/mg protein to as high as 76 fmol/mg protein in different patient groups, and MF/10HPF varied from 6 to 21. Patients were stratified into different groups that enabled better evaluation of treatment outcome. Patients could also be combined into three groups with significantly different survival rates (p < 0.0001). Stratified multivariate survival analysis show that prognostic markers a) are interdependent, and their cut-off values vary depending on other tumor characteristics, and b) if used in a systematic way, they can be used to guide treatment decisions.


Assuntos
Neoplasias da Mama/mortalidade , Adulto , Idoso , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Receptores de Estrogênio/análise
20.
Eur J Obstet Gynecol Reprod Biol ; 70(1): 69-74, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9031923

RESUMO

BACKGROUND: Malignant transformation to endometriosis is a well documented phenomenon that occurs most commonly in the ovaries with cancer arising in extra-ovarian endometriosis being a rare event. METHODS: A retrospective clinical-pathological evaluation of eleven cases with malignant tumors arising in endometriosis was performed to evaluate the prognostic impact of various factors. Nuclear DNA content (ploidy) was assessed through flow cytometric study. RESULTS: Ovarian origin was identified in eight cases and three were associated with extra-ovarian endometriosis. Histologic type was endometrioid carcinoma in ten patients. The eleventh case had high grade endometrial stromal sarcoma. All tumors were diploid with no relation to stage, grade, or clinical outcome. The S-phase fraction (SPF) was analyzed in nine patients and no correlation could be demonstrated with any histologic parameters or clinical outcome. CONCLUSIONS: The DNA content seems to have no association with the classical prognostic parameters in these cases.


Assuntos
Endometriose/patologia , Neoplasias dos Genitais Femininos/patologia , Adulto , Idoso , Carcinoma Endometrioide/etiologia , Carcinoma Endometrioide/patologia , Transformação Celular Neoplásica , DNA/análise , Neoplasias do Endométrio/etiologia , Neoplasias do Endométrio/patologia , Endometriose/complicações , Endometriose/cirurgia , Feminino , Citometria de Fluxo , Neoplasias dos Genitais Femininos/etiologia , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/etiologia , Neoplasias Ovarianas/patologia , Neoplasias Pélvicas/etiologia , Neoplasias Pélvicas/patologia , Neoplasias Pélvicas/terapia , Ploidias , Prognóstico , Estudos Retrospectivos , Sarcoma/etiologia , Sarcoma/patologia , Neoplasias Vaginais/etiologia , Neoplasias Vaginais/patologia , Neoplasias Vaginais/cirurgia
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