Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 87
Filtrar
1.
Ann Oncol ; 25(4): 858-863, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24667718

RESUMO

BACKGROUND: Stage II rectal cancers comprise a heterogeneous group, and there is significant variability in practise with regards to adjuvant chemotherapy; the survival benefit of chemotherapy is perceived to be <4% in these patients. However, in recent years, the emergence of additional prognostic factors such as extramural venous invasion (EMVI) suggests that there may be sub-stratification of stage II tumours and, further, we may be under-estimating the benefit adjuvant chemotherapy provides in high-risk patients. This study examined the outcomes of patients with stage II and III rectal cancer to determine whether EMVI status influences disease-free survival (DFS). PATIENTS AND METHODS: An analysis of a prospectively maintained database was conducted of patients presenting with rectal cancer between 2006 and 2012. All patients underwent curative surgery and had no evidence of metastases at presentation. Clinicopathological factors were compared between stage II and III disease. The primary end point was 3-year DFS; univariate and multivariate analysis was carried out using Cox proportional hazards regression models; hazard ratios (HR) with 95% confidence intervals (CIs) were calculated. RESULTS: Four hundred and seventy-eight patients were included: 233 stage II; 245 stage III. The prevalence of EMVI was 34.9%; 57 stage II patients (24.5%) and 110 stage III patients (44.9%). On multivariate analysis, only EMVI status was a significant factor for DFS. The adjusted HR for EMVI either alone or in combination with nodal involvement was 2.08 (95% CI 1.10-2.95) and 2.74 (95% CI 1.66-4.52), respectively. CONCLUSION: EMVI is an independently poor prognostic factor for DFS for both stage II and stage III rectal cancer. These results demonstrate that there is risk-stratification within stage II tumours which affects prognosis. When discussing the use of adjuvant chemotherapy with patients that have EMVI-positive stage II tumours, these results provide evidence for a similarly increased risk of distant failure as stage III disease without venous invasion.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Idoso , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Período Pré-Operatório , Prognóstico , Modelos de Riscos Proporcionais , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Resultado do Tratamento
2.
Eur J Surg Oncol ; 40(2): 240-5, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24286808

RESUMO

INTRODUCTION: Mucinous tumours of the rectum are characterised by an abundance of extracellular mucin within the tumour complex. They are known to have a poor prognosis compared to non-mucinous adenocarcinomas. The effect of adjuvant chemotherapy on the survival outcomes of patients with mucinous cancer remains unclear. This study evaluated the 5-year overall survival of patients with mucinous rectal cancer following optimal TME surgery to determine whether adjuvant chemotherapy conferred a survival benefit. METHODS: An analysis of a prospectively-maintained database was conducted of patients presenting with mucinous rectal cancer between 2000 and 2010. Patients with mucinous tumours were identified from final pathology reports of the surgical resection specimens. The primary outcome was 5-year overall survival; univariate and multivariate analysis was performed using Cox proportional hazards regression models. RESULTS: A total of 191 patients were included for analysis with mean age of presentation 64.6 years (36-88 ± 11). On the fully adjusted multivariate model, EMVI status (HR 1.853, 95% CI 1.081-3.175) and not being given adjuvant chemotherapy (HR 2.888, 95% CI 1.801-4.633) were significant for disease recurrence. The 5-year overall survival for patients that had undergone adjuvant chemotherapy was 66.1% compared with 35.2% (Mantel Cox log-rank test - p < 0.0001). CONCLUSION: This study demonstrates that adjuvant chemotherapy is an independent factor for improvement in overall survival in patients with mucinous adenocarcinoma. Therefore, patients who have undergone TME surgery for mucinous carcinoma of the rectum should be offered adjuvant chemotherapy even in the absence of other high-risk features for poor outcomes.


Assuntos
Adenocarcinoma Mucinoso/tratamento farmacológico , Neoplasias Retais/tratamento farmacológico , Reto/cirurgia , Adenocarcinoma Mucinoso/mortalidade , Adenocarcinoma Mucinoso/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Adjuvante , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Prospectivos , Neoplasias Retais/mortalidade , Neoplasias Retais/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
4.
Br J Pharmacol ; 156(4): 609-25, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19226253

RESUMO

BACKGROUND AND PURPOSE: The kisspeptins are critical regulators of reproduction and a therapeutic target for reproductive disease. Intracerebroventricular (i.c.v.) or peripheral injection of kisspeptin potently stimulates the hypothalamic-pituitary gonadal (HPG) axis via gonadotrophin-releasing hormone (GnRH). However, little is known regarding the effects of kisspeptin administration on testicular function. We investigated the mechanism(s) of kisspeptin-induced testicular degeneration in the rat. EXPERIMENTAL APPROACH: Kisspeptin-54 (50 nmol.day(-1)) was continuously administered subcutaneously (6 h to 3 days) to male Wistar rats and reproductive hormones and testicular histology analysed. We also investigated the effects of a single subcutaneous injection of 0.5, 5 or 50 nmol kisspeptin-54. In order to determine whether the testicular degeneration observed is peripherally or centrally mediated, we investigated effects of i.c.v. injections of 5 nmol kisspeptin-54 and pre-administered a GnRH-receptor antagonist (cetrorelix) to rats peripherally treated with kisspeptin-54. KEY RESULTS: Continuous subcutaneous administration of kisspeptin-54 caused testicular degeneration after only 12 h, when gonadotrophins were still markedly raised, suggesting that the degeneration is independent of the desensitization of the HPG axis to kisspeptin-54. Furthermore, a single subcutaneous injection of kisspeptin-54 caused dose-dependent testicular degeneration. Continuous kisspeptin-54 administration is thus not required to cause testicular degeneration. Pretreatment with cetrorelix blocked kisspeptin-induced testicular degeneration, and a single i.c.v. injection of kisspeptin-54 caused testicular degeneration, suggesting it is GnRH-mediated. CONCLUSIONS AND IMPLICATIONS: Kisspeptin-induced testicular degeneration appears to be centrally mediated, and result from acute hyper-stimulation of the HPG axis. Doses must be carefully considered if kisspeptin is to be used therapeutically.


Assuntos
Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Receptores Acoplados a Proteínas G/fisiologia , Testículo/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Inibinas/sangue , Injeções Intraventriculares , Injeções Subcutâneas , Masculino , Ratos , Ratos Wistar , Receptores Acoplados a Proteínas G/administração & dosagem , Receptores de Kisspeptina-1 , Testículo/patologia , Fatores de Tempo
5.
Br J Dermatol ; 159(1): 152-61, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18460029

RESUMO

BACKGROUND: Fluorescence lifetime imaging (FLIM) is a novel imaging technique that generates image contrast between different states of tissue due to differences in fluorescence decay rates. OBJECTIVES: To establish whether FLIM of skin autofluorescence can provide useful contrast between basal cell carcinomas (BCCs) and surrounding uninvolved skin. METHODS: Unstained excision biopsies of 25 BCCs were imaged en face with FLIM following excitation of autofluorescence with a 355 nm pulsed ultraviolet laser. RESULTS: Using FLIM we were able to distinguish areas of BCC from surrounding skin in an ex vivo study. Significant reductions in mean fluorescence lifetimes between areas of BCC and areas of surrounding uninvolved skin were demonstrated (P < 0.0001). These differences were apparent irrespective of the decay model used to calculate the fluorescence lifetimes (single vs. stretched exponential) or the long-pass filter through which the emitted autofluorescence was collected (375 vs. 455 nm). Conversely, there was no significant difference between the BCC and uninvolved areas of each sample when mean autofluorescence intensities were examined. Moreover, wide-field false-colour images of fluorescence lifetimes clearly discriminated areas of BCC from the surrounding uninvolved skin. CONCLUSIONS: We therefore believe that FLIM has a potential future clinical role in imaging BCCs for rapid and noninvasive tumour delineation and as an aid to determine adequate excision margins with best preservation of normal tissue.


Assuntos
Carcinoma Basocelular/diagnóstico , Diagnóstico por Imagem/métodos , Neoplasias Cutâneas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Fluorescência , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Sensibilidade e Especificidade
6.
Rev Sci Instrum ; 78(12): 123101, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18163714

RESUMO

The autofluorescence of biological tissue can be exploited for the detection and diagnosis of disease but, to date, its complex nature and relatively weak signal levels have impeded its widespread application in biology and medicine. We present here a portable instrument designed for the in situ simultaneous measurement of autofluorescence emission spectra and temporal decay profiles, permitting the analysis of complex fluorescence signals. This hyperspectral fluorescence lifetime probe utilizes two ultrafast lasers operating at 355 and 440 nm that can excite autofluorescence from many different biomolecules present in skin tissue including keratin, collagen, nicotinamide adenine dinucleotide (phosphate), and flavins. The instrument incorporates an optical fiber probe to provide sample illumination and fluorescence collection over a millimeter-sized area. We present a description of the system, including spectral and temporal characterizations, and report the preliminary application of this instrument to a study of recently resected (<2 h) ex vivo skin lesions, illustrating its potential for skin cancer detection and diagnosis.


Assuntos
Biomarcadores Tumorais/análise , Medições Luminescentes/instrumentação , Neoplasias Cutâneas/diagnóstico , Espectrometria de Fluorescência/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Técnicas de Sonda Molecular , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Fluorescência/métodos
7.
J Clin Pathol ; 59(9): 903-11, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16935969

RESUMO

Specimens of bone marrow trephine biopsy (BMT) are transported and fixed in acetic acid-zinc-formalin fixative, decalcified in 10% formic acid-5% formaldehyde and processed with other specimens to paraffin-wax embedding. Sections, 1-microm-thick, are cut by experienced histotechnologists and used for haematoxylin and eosin, Giemsa, reticulin silver and other histological stains. Further, all immunohistochemical procedures used in the laboratory, including double immunostaining, can be used on these sections with no or minimal modifications. About 10,000 BMT specimens have been analysed using this procedure since 1997 and diseases involving the bone marrow have been classified successfully. More recently, standardised polymerase chain reaction-based analysis and mRNA in situ hybridisation studies have been conducted. Excellent morphology with good antigen, DNA and RNA preservation is offered by the Hammersmith Protocol.


Assuntos
Exame de Medula Óssea/métodos , Medula Óssea/patologia , Biópsia/métodos , Exame de Medula Óssea/normas , Protocolos Clínicos , DNA de Neoplasias/análise , Humanos , Reação em Cadeia da Polimerase/métodos , Coloração e Rotulagem/métodos , Fixação de Tecidos/métodos
9.
Opt Lett ; 29(19): 2249-51, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15524370

RESUMO

We report the development of a high-speed wide-field fluorescence-lifetime imaging (FLIM) system that provides fluorescence-lifetime images at rates of as many as 29 frames/s. A FLIM multiwell plate reader and a potentially portable FLIM endoscopic system operating at 355-nm excitation have been demonstrated.


Assuntos
Algoritmos , Endoscópios , Interpretação de Imagem Assistida por Computador/métodos , Microscopia de Fluorescência/métodos , Sistemas On-Line/instrumentação , Espectrometria de Fluorescência/métodos , Gravação em Vídeo/instrumentação , Endoscopia/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Estudos de Viabilidade , Gravação em Vídeo/métodos
10.
Mol Pathol ; 56(6): 353-61, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14645699

RESUMO

BACKGROUND/AIMS: Overexpression of the G1 cyclins, D1 and E, and/or downregulation of p27(Kip1) allow uncontrolled tumour cell proliferation. This study investigated the relation between these three cell cycle proteins and tumour proliferation in bladder cancer. METHOD: Nuclear expression of cyclin D1, cyclin E, and p27(Kip1) was determined immunohistochemically in 52 primary transitional cell carcinomas, and the Ki-67 proliferation marker was also assessed. For each protein, the percentage of positive tumour cell nuclei was determined and analysed as a continuous variable. RESULTS: Advancing tumour grade and pathological stage were accompanied by increasing proliferation indices, but decreasing p27(Kip1) and cyclin D1 expression, with no significant change in cyclin E expression. Overall, cyclin D1 and E expression did not correlate with proliferation. However, in cyclin D1 overexpressing tumours (> or = 5% nuclei positive), the level of cyclin D1 expression positively correlated with proliferation. The correlation between cyclin E expression and proliferation changed from positive to negative with increasing levels of cyclin E expression, accompanied by a coordinate increase in p27(Kip1) expression. Overall, there was an inverse association between p27(Kip1) expression and proliferation. However, a subset of tumours displayed high proliferation indices despite high p27(Kip1) expression. The G1 cyclin index (sum of the level of expression of cyclins D1 and E) correlated positively with proliferation in superficial but not muscle invasive tumours. This correlation was stronger when the G1 cyclin index was adjusted for p27(Kip1) expression. CONCLUSION: These findings support a role for these proteins in the proliferation, differentiation, and progression of bladder transitional cell carcinomas.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células de Transição/química , Ciclina E/análise , Neoplasias da Bexiga Urinária/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/patologia , Proteínas de Ciclo Celular/análise , Divisão Celular , Ciclina D1/análise , Inibidor de Quinase Dependente de Ciclina p27 , Feminino , Humanos , Imuno-Histoquímica/métodos , Antígeno Ki-67/análise , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estatísticas não Paramétricas , Proteínas Supressoras de Tumor/análise , Neoplasias da Bexiga Urinária/patologia
11.
J Pathol ; 194(3): 373-83, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11439371

RESUMO

Human MUC1 mucin is a high-molecular-weight transmembrane glycoprotein, which is apically expressed in the majority of glandular epithelia. During embryonic development, changes in the pattern of MUC1 mucin expression coincide with the onset of glandular differentiation. This mucin is also frequently overexpressed and aberrantly glycosylated in carcinomas. To investigate the potential role of MUC1 mucin in morphogenesis, a full length MUC1 cDNA was transfected into murine mammary adenocarcinoma (410.4) and Madin-Darby canine kidney (MDCK) cells. This generated four clonal cell lines. Western blotting, FACS analysis, and immunohistochemistry confirmed expression of MUC1. All four MUC1-expressing clones demonstrated altered morphogenesis when cultured in three-dimensional type I collagen gels. While parental and vector control 410.4 cells formed compact spherical structures, the MUC1-expressing clones formed complex branching structures. Similarly, while parental and vector control MDCK cells formed small circumscribed colonies with a central lumen, the MUC1-expressing clones formed elongated tubules. MUC1 expression was also associated with reduced cellular cohesion and enhanced migration on type I collagen-coated surfaces for all except one of the clones, which expressed only low levels of MUC1 on the cell surface. These results show that MUC1 expression stimulates morphogenetic changes in two distinct epithelial cell lines. Taken together with previous observations on MUC1 expression in embryonic development and carcinomas, this finding suggests that MUC1 may induce changes in tissue architecture in both normal development and cancer.


Assuntos
Glândulas Endócrinas/crescimento & desenvolvimento , Mucina-1/fisiologia , Adenocarcinoma , Animais , Adesão Celular , Linhagem Celular , Movimento Celular , Cães , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Rim , Camundongos , Morfogênese , Mucina-1/análise , Mucina-1/genética , Neoplasias Experimentais , Transfecção , Células Tumorais Cultivadas
12.
J Pathol ; 193(4): 522-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11276013

RESUMO

Functional overexpression of Bcl-2 has been reported to confer an anti-apoptotic potential in a variety of cell types. The role of Bcl-2 in epithelial cell-cycle control and in interactions with other cell-cycle regulators is not clearly understood. Its expression has been correlated with the hormono- and chemo-resistant phenotype in advanced prostate cancer. The aim of this study was to investigate the mechanisms through which Bcl-2 mediates increased cytotoxic chemoresistance by assessing alterations in the expression of cell death regulatory molecules. The DU145 human prostatic adenocarcinoma cell line was stably transfected with a Bcl-2 encoding expression plasmid. Two Bcl-2 transfectants, DKC9 and DKC11, were expanded for further study. The effects of Bcl-2 expression on cellular proliferation, cell death (+/- adriamycin or thapsigargin), and expression of cell-cycle/death regulators (p53, PCNA, Bax, Bak, Bcl-X(L)) were evaluated. Compared with controls, Bcl-2 transfectants showed no difference in the rate of proliferation, a decrease in p53 (approximately two-fold), an increase in Bax (approximately two-fold) and PCNA (approximately three-fold), and no change in the levels of Bcl-X(L) and Bak proteins. DKC9 and DKC11 also exhibited a significantly increased chemoresistance to adriamycin (0.0025-5 microM) and thapsigargin (0.0025-5 microM) compared with controls. In the presence of thapsigargin or adriamycin, levels of Bcl-2 and its heterodimeric partner Bax were elevated approximately two-fold with no change in Bak in Bcl-2 transfectants in contrast to controls, where Bak was increased (two-fold). This is the first study to demonstrate that Bcl-2 transfection modulates the expression of mutant p53, Bax, and PCNA in prostate cancer cells. Moreover, Bcl-2 overexpression conferred a significant cytotoxic chemoresistance and altered the balance of expression of death promoters (from Bak, a dominant death promoter in controls, to Bax) in response to thapsigargin and adriamycin.


Assuntos
Adenocarcinoma/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes bcl-2 , Neoplasias da Próstata/genética , Adenocarcinoma/patologia , Antineoplásicos/farmacologia , Proteínas de Ciclo Celular/metabolismo , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Humanos , Masculino , Neoplasias da Próstata/patologia , Tapsigargina/farmacologia , Transfecção , Células Tumorais Cultivadas
13.
J Pathol ; 192(4): 446-54, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11113861

RESUMO

A unique feature of SW480 and SW620 colon carcinoma cell lines is that they are derived from primary and secondary tumours resected from a single patient. As such, they may represent a valuable resource for examining genetic changes late in colon cancer progression. In order to verify this, both cell lines have been characterized to determine whether phenotypic differences have been retained despite long-term cell culture in vitro. The primary tumour-derived SW480 cells have an epithelioid morphology in vitro, while metastasis-derived SW620 cells have a fibroblast-like appearance. Xenografts of SW480 cells form gland-like structures in vivo, while SW620 xenografts form solid sheets of tumour cells. SW620 cells have a higher BrdU labelling index than SW480 cells, and are more highly tumourigenic and metastatic. Furthermore, SW620 cells show less susceptibility to apoptosis induction by TNFalpha and anti-Fas monoclonal. Findings from these investigations therefore indicate that SW480 and SW620 cell lines do show appropriate phenotypic differences and represent an interesting model for studying the genetic events in the late stages of colon cancer progression.


Assuntos
Neoplasias do Colo/patologia , Modelos Biológicos , Animais , Apoptose , Adesão Celular , Ciclo Celular , Movimento Celular , Progressão da Doença , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , Transplante de Neoplasias , Transplante Heterólogo , Células Tumorais Cultivadas
14.
BJU Int ; 86(6): 736-41, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11069387

RESUMO

OBJECTIVE: To assess the level and morphological distribution of cyclooxygenase (COX)-1 and -2 in human prostates and to determine any association with the Gleason grade of prostate cancer. Materials and methods The study comprised 30 samples from patients with benign prostatic hyperplasia (BPH) and 82 with prostate cancer. Immunohistochemistry was used to assess the expression of COX-1 and -2, and 13 samples were also assessed using immunoblotting (six BPH and seven cancers). RESULTS: For both BPH and prostate cancer, COX-1 expression was primarily in the fibromuscular stroma, with variable weak cytoplasmic expression in glandular/neoplastic epithelial cells. In contrast, COX-2 expression differed markedly between BPH and cancer. In BPH there was membranous expression of COX-2 in luminal glandular cells and no stromal expression. In cancer the stromal expression of COX-2 was unaltered, but expression by tumour cells was significantly greater (P = 0.008), with a change in the staining pattern from membranous to cytoplasmic (P < 0.001). COX-2 expression was significantly higher in poorly differentiated than in well differentiated tumours (P < 0.001). These results were supported by immunoblotting, which showed similar levels of COX-1 in both BPH and cancer, but four times greater expression of COX-2 in cancer than in BPH. CONCLUSION: This is the first study to assess the co-expression of COX-1 and COX-2 proteins in benign and malignant human prostates, and showed the induction and significantly greater expression of COX-2 in cancer, which was also associated with tumour grade. The regular use of nonsteroidal anti-inflammatory drugs is associated with a reduced incidence of cancers. The present results provide the basis for a potential role for COX-2 inhibitors in the prevention and treatment of prostate cancer.


Assuntos
Isoenzimas/metabolismo , Proteínas de Neoplasias/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Hiperplasia Prostática/metabolismo , Neoplasias da Próstata/metabolismo , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Ciclo-Oxigenase 2 , Humanos , Imuno-Histoquímica , Masculino , Proteínas de Membrana , Pessoa de Meia-Idade , Hiperplasia Prostática/terapia , Neoplasias da Próstata/terapia
15.
J Pathol ; 190(1): 107-13, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10641000

RESUMO

In the small intestinal mucosa, four principal epithelial cell lineages are found - the Paneth, goblet, enterocytic, and endocrine cell lineages. These cell lineages are terminally differentiated, non-proliferative, and derive from multipotent stem cells near the bases of the crypts of Lieberkühn. Intestinal metaplasia of the stomach is considered to be a premalignant condition. Since proliferative populations in this condition are not well studied, this feature was examined using double-labelling immunohistochemical and histochemical methods; 20 paraffin blocks of small intestinal mucosa and 24 paraffin blocks of intestinal metaplasia of the human stomach were studied. Double-staining was carried out with MIB-1 as a proliferation marker, with Alcian blue for goblet cells, anti-chromogranin A for endocrine cells, and p-dimethylaminobenzaldehyde-nitrite for Paneth cells. Double-labelling showed that numerous Paneth cells and goblet cells in intestinal metaplasia were in the cell cycle, but endocrine cells appeared non-proliferative. Double-labelled Paneth or endocrine cells were not seen in the control small intestinal mucosa but scanty double-labelled goblet cells were observed in normal intestinal mucosa. In intestinal metaplasia of the stomach, there is evidence of cell-cycle deregulation in the goblet and Paneth cell lineages. These observations have considerable implications for the biology and histogenesis of Paneth cells, goblet cells, and endocrine cells, and the nature of intestinal metaplasia in the gastric mucosa.


Assuntos
Células Enteroendócrinas/patologia , Células Caliciformes/patologia , Celulas de Paneth/patologia , Lesões Pré-Cancerosas/patologia , Neoplasias Gástricas/patologia , Divisão Celular , Histocitoquímica , Humanos , Imuno-Histoquímica , Mucosa Intestinal/citologia , Mucosa Intestinal/patologia , Intestino Delgado , Metaplasia
16.
J Clin Oncol ; 17(7): 2180-9, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10561274

RESUMO

PURPOSE: This trial was designed to test the safety and efficacy of a tumor-specific genetic prodrug activation therapy targeted by use of the human erbB-2 gene promoter. The erbB-2 oncogene is overexpressed in approximately 20% of cases of breast cancer and is associated with poor prognosis. PATIENTS AND METHODS: Twelve breast cancer patients received transcriptionally targeted gene therapy in a phase I clinical trial using direct intratumoral injection of plasmid construct combined with systemic administration of prodrug. The genetic prodrug activation therapy is specifically targeted to erbB-2-overexpressing breast cancer cells by use of a therapeutic cassette that contains the Escherichia coli cytosine deaminase gene driven by the tumor-specific erbB-2 promoter, thus allowing activation of fluorocytosine to the active cytotoxic fluorouracil only within tumor cells that express the oncogene. RESULTS: The approach was shown to be safe and to result in targeted gene expression in up to 90% of cases. Using a number of different assays, we demonstrated that significant levels of expression of the suicide gene were specifically restricted to erbB-2-positive tumor cells, confirming the selectivity of the approach. CONCLUSION: The results of this study, the first targeted gene therapy for breast cancer and the first to use the cytosine deaminase system in human subjects, are encouraging for the development of genetic prodrug activation therapies that exploit the transcriptional profile of cancer cells.


Assuntos
Neoplasias da Mama/terapia , Fluoruracila/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes erbB-2/efeitos dos fármacos , Terapia Genética/métodos , Pró-Fármacos/uso terapêutico , Adulto , Idoso , Neoplasias da Mama/patologia , Citosina Desaminase , Feminino , Humanos , Pessoa de Meia-Idade , Nucleosídeo Desaminases/genética , Plasmídeos , Pós-Menopausa
17.
Br J Cancer ; 81(3): 431-9, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10507767

RESUMO

To overcome the disadvantages of bi-specific antibody methodologies in vivo, a novel antibody approach has been designed to improve tumour targeting and effector to target ratio. The technique involves biotinylated anti-CD3 Fab fragments and streptavidinylated anti-tumour monoclonal antibodies (mAbs) that can spontaneously form cross-links. We describe here a method for the direct cross-linking of sulphydryl-conjugated HMFG1 (anti-MUC1 mucin mAb) to streptavidin by sulphosuccinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate. Fab fragments generated by papain digestion of the 1452C11 antibody (anti-CD3 mAb without Fc to avoid peripheral activation of T-cells) were biotinylated with NHS-Iminobiotin. MUC1-transfected BALB/c breast cancer cell lines 413BCR and 425CCR and the parental cell line (410.4) were labelled with streptavidinylated mouse anti-MUC1 mucin mAb. BALB/c effector T-cells were separately labelled with biotinylated anti-CD3 Fab fragments (1452C11) and mixed with tumour cells in different effector to target ratios. Percentage of killing was assessed using the 51Cr cytotoxicity assay. Seventy per cent lysis was measured in the case of 413BCR (high MUC1 mucin expressor) and 40% in the case of 425CCR (low expressor) cell line. No lysis was apparent in the MUC1 negative cell line. These results demonstrate that the novel T-cell redirecting approach we have developed can produce effective immune lysis of target cells in vitro.


Assuntos
Anticorpos Biespecíficos/imunologia , Anticorpos Antineoplásicos/imunologia , Complexo CD3/imunologia , Imunoterapia , Mucina-1/imunologia , Proteínas de Neoplasias/imunologia , Animais , Especificidade de Anticorpos , Biotina , Feminino , Fragmentos Fab das Imunoglobulinas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Mucina-1/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Estreptavidina , Linfócitos T/imunologia , Transfecção
18.
Am J Pathol ; 154(5): 1335-43, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10329586

RESUMO

Differential gene expression between the androgen sensitive human prostate cancer cell line LNCaP and an insensitive clonal variant, LNCaP-r, was demonstrated by suppression subtractive hybridization. Twenty-one sequences were identified of which 9 are homologous to known genes, 11 are represented by expressed sequence tags (ESTs), and 1 is novel. We present data for 5 of 7 sequences confirmed to be differentially expressed by Northern blot analysis and semiquantitative RT-PCR. Only one gene, fibronectin (FN), was highly overexpressed (>60-fold) in LNCaP-r cells, consistent with previously reported overexpression of FN in prostate cancer. Four sequences were down-regulated in LNCaP-r cells, including an inactive variant of the E2 ubiquitin conjugating enzyme (UEV-1), a novel metalloproteinase-related collagenase (PM5), and a potential tumor suppressor gene (breast basic conserved gene, BBC1). UEV-1 is multifunctional, regulates the cell cycle via cdk1, has homology to MMS2 and likewise functions as a DNA protection protein, and also has homology to TSG101. Aberrant splice variants of TSG101 occur frequently in both breast and prostate cancer, but its mechanism of action is unknown. FN, BBC1, and UEV-1 localize to regions of chromosomal aberration (2q3.4, 16q24.3, and 20q13.2, respectively) associated with advanced prostate cancer and thus may be highly relevant to disease progression.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Aberrações Cromossômicas , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias da Próstata/tratamento farmacológico , Proteínas Ribossômicas , Mapeamento Cromossômico , Cromossomos Humanos Par 16 , Cromossomos Humanos Par 2 , Cromossomos Humanos Par 20 , Fibronectinas/genética , Humanos , Masculino , Proteínas de Neoplasias/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
19.
Lab Invest ; 79(5): 537-46, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10334565

RESUMO

Members of the trefoil factor (TFF) family are highly expressed in endodermal ulcerative wound healing and selectively in neoplastic proliferation of various glandular epithelia. There is some evidence that TFF1 and TFF3 affect cell motility, are indirectly involved in growth suppression, and are associated with mucin expression. TFF2 is co-expressed with TFF1 in gastric surface epithelial cells, but its potential role in vivo is unclear. We analyzed potential effects on cell proliferation and morphogenesis of TFF2 on a panel of epithelial and mesenchymal cell lines. TFF2 had no measurable effect on the proliferation of any of the cell lines tested. In type 1 collagen lattices, TFF2 at a low concentration (25-100 nM) induced the formation of highly complex branched structures in the breast carcinoma cell line MCF-7 over a period of 14 to 42 days. No significant effect was shown with other cell lines. This morphogenic effect was abolished by monoclonal antibodies specific for either TFF2 or TFF1. TFF2 did not affect cell motility in MCF-7 cells as measured by videomicroscopy, in contrast to previous studies using TFF1. TFF2-treated MCF-7 colonies showed a 30% reduction in the number of apoptotic bodies, corroborated by trypan blue exclusion and DNA fragmentation ELISA, indicating TFF2 promotes cell survival via inhibition of apoptosis and can act as a morphogen in the presence of TFF1. These properties may complement the actions of TFF1 as a motogen and may explain differential expression in endodermal wound healing.


Assuntos
Substâncias de Crescimento/farmacologia , Mucinas , Proteínas Musculares , Neuropeptídeos , Peptídeos/farmacologia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Substâncias de Crescimento/imunologia , Histocitoquímica , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Peptídeos/imunologia , Fator Trefoil-2 , Fator Trefoil-3 , Células Tumorais Cultivadas/citologia , Células Tumorais Cultivadas/efeitos dos fármacos
20.
J Clin Pathol ; 52(1): 29-34, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10343609

RESUMO

AIM: To investigate the correlation between androgen receptor expression and fibroblast growth factor 8 (FGF8) mRNA levels. METHODS: 39 human prostate cancers and 14 benign prostatic hypertrophy specimens were examined immunohistochemically for androgen receptor expression and by in situ hybridisation and reverse transcription polymerase chain reaction for FGF8 expression. RESULTS: In 39 tumours there was a statistically significant negative correlation between tumour grade and FGF8 expression and a positive correlation between FGF8 and androgen receptor expression. All 14 benign hypertrophy specimens expressed moderate to high levels of FGF8 and androgen receptor. CONCLUSIONS: Loss of FGF8 may be a factor involved in the development of prostatic cancer.


Assuntos
Fatores de Crescimento de Fibroblastos/biossíntese , Hiperplasia Prostática/metabolismo , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Fator 8 de Crescimento de Fibroblasto , Fatores de Crescimento de Fibroblastos/genética , Expressão Gênica , Humanos , Hibridização In Situ , Masculino , Proteínas de Neoplasias/metabolismo , Hiperplasia Prostática/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , RNA Mensageiro/genética , RNA Neoplásico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...