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1.
Ann Oncol ; 21(5): 942-8, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19840953

RESUMEN

BACKGROUND: Patients with breast cancer brain metastasis are a heterogeneous group in relation to tumor biology and outcome. MATERIALS AND METHODS: The group of 222 breast cancer patients with brain metastasis was divided into three biological subgroups. The propensity of biological subtypes for metastases to the brain and survivals depending on biological subtype, recursive partitioning analysis of Radiation Therapy Oncology Group (RPA RTOG) prognostic class and the use of systemic treatment after whole-brain radiotherapy were assessed. RESULTS: The rate of patients with triple-negative, human epidermal growth factor receptor 2 (HER2)-positive and luminal breast cancer with brain metastases was 28%, 53% and 19%, respectively. Median survival from brain metastases in triple-negative, HER2-positive and luminal subtype was 3.7, 9 and 15 months, respectively. Median survival from brain metastases in RPA RTOG prognostic class I, II and III was 15, 11 and 3 months, respectively. In the luminal and in the triple-negative subtype, systemic therapy prolonged survival from 3 to 14 months and from 3 to 4 months, respectively. In HER2-positive subtype, median survival without further treatment, after chemotherapy and after chemotherapy with targeted therapy were 3, 8 and 11 months, respectively. CONCLUSIONS: HER2-positive and triple-negative breast cancers have special predilection for metastases to the brain. Survival from brain metastases depended on performance status and the use of systemic treatment.


Asunto(s)
Neoplasias Encefálicas/mortalidad , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Irradiación Craneana , Neoplasias Ductales, Lobulillares y Medulares/mortalidad , Adulto , Anciano , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/radioterapia , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/radioterapia , Neoplasias Ductales, Lobulillares y Medulares/secundario , Receptor ErbB-2/metabolismo , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento , Adulto Joven
2.
Breast Cancer Res Treat ; 116(3): 471-8, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18686028

RESUMEN

FEZ1/LZTS1 is a tumor suppressor gene located in chromosomal band 8p22, and methylation has been identified as a mechanism for its loss of function in tumors. Chromosomal deletion at 8p22 is also frequent in breast cancer. We therefore examined whether LZTS1 plays a role in breast cancer. We analyzed expression of LZTS1 at both the RNA and protein levels, and promoter methylation in a number of primary tumors and cell lines from breast cancer. We also examined the association between LZTS1 expression and different clinicopathological parameters of breast cancer. We found that the expression of LZTS1 mRNA was reduced in 25 of 50 (50%) primary tumors and 29 of 30 (97%) breast cancer cell lines. Immunohistochemical staining showed that LZTS1 protein was absent or down-regulated in 72 (72%) of 100 primary breast carcinomas. Reduced expression of LZTS1 at either the RNA or protein level was significantly correlated with lymph node metastases (P < 0.05). DNA methylation analysis revealed that the LZTS1 gene was frequently methylated in both cell lines and primary tumors from breast cancer, and the extent of DNA methylation was correlated with reduced expression of the gene. These findings suggest that LZTS1 plays a role in the development and progression of breast cancer at least through promoter methylation-mediated transcriptional downregulation.


Asunto(s)
Neoplasias de la Mama/genética , Carcinoma Intraductal no Infiltrante/genética , Carcinoma Papilar/genética , Metilación de ADN , Neoplasias Ductales, Lobulillares y Medulares/genética , Regiones Promotoras Genéticas/genética , Factores de Transcripción/genética , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Carcinoma Intraductal no Infiltrante/metabolismo , Carcinoma Intraductal no Infiltrante/secundario , Carcinoma Papilar/metabolismo , Carcinoma Papilar/secundario , Estudios de Casos y Controles , Cromosomas Humanos Par 8/genética , Islas de CpG , Cartilla de ADN/química , Regulación hacia Abajo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Técnicas para Inmunoenzimas , Persona de Mediana Edad , Invasividad Neoplásica , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/secundario , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Transcripción/metabolismo , Células Tumorales Cultivadas
3.
Clin Cancer Res ; 12(5): 1470-8, 2006 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-16533770

RESUMEN

PURPOSE: hMena (ENAH), a cytoskeleton regulatory protein involved in the regulation of cell motility and adhesion, is overexpressed in breast cancer. The aim of this study was to define at what stage of breast carcinogenesis hMena is overexpressed and to correlate hMena overexpression with established prognostic factors in breast cancer, focusing on human epidermal growth factor receptor-2 (HER-2). EXPERIMENTAL DESIGN: hMena expression was assessed immunohistochemically in a prospective cohort of cases (n = 360) encompassing a highly representative spectrum of benign breast diseases associated with different risk of transformation, in situ, invasive, and metastatic tumors. Correlations with conventional pathologic and prognostic variables, such as proliferation index, hormonal receptor status, and HER-2 overexpression, were also evaluated. In vitro experiments were done to study the effect of neuregulin-1 and Herceptin treatments on hMena expression. RESULTS: hMena protein is undetectable in normal breast and is weakly expressed in a small percentage of low-risk benign diseases (9%), but displays a progressive and significant increase of positivity in benign lesions at higher risk of transformation (slightly increased risk 43%; moderate increased risk 67%), in in situ (72%), invasive (93%), and metastatic breast cancer (91%). A significant direct correlation with tumor size (P = 0.04), proliferation index (P < 0.0001), and HER-2 overexpression (P < 0.0001) and an inverse relationship with estrogen (P = 0.036) and progesterone receptors (P = 0.001) are found in invasive carcinomas. In vitro experiments show that neuregulin-1 up-regulates, whereas Herceptin down-regulates, hMena expression. CONCLUSIONS: Our data provide new insights into the relevance of actin-binding proteins in human breast carcinogenesis and indicate hMena overexpression as a surrogate indicator in breast disease management.


Asunto(s)
Neoplasias de la Mama/metabolismo , Transformación Celular Neoplásica , Proteínas del Citoesqueleto/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales Humanizados , Biomarcadores de Tumor , Mama , Neoplasias de la Mama/patología , Carcinoma in Situ/metabolismo , Carcinoma in Situ/patología , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/secundario , Carcinoma Papilar/metabolismo , Carcinoma Papilar/secundario , Proliferación Celular , Estudios de Cohortes , Femenino , Humanos , Persona de Mediana Edad , Invasividad Neoplásica/patología , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/secundario , Neurregulina-1/farmacología , Pronóstico , Estudios Prospectivos , Factores de Riesgo , Trastuzumab
4.
Cancer Lett ; 244(2): 203-10, 2006 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-16469432

RESUMEN

The aim of this study is to investigate the possible role of inhibitor of DNA binding (Id-1) overexpression in human breast cancer. We examined Id-1 expression by immunohistochemistry in 263 human breast cancers, 15 in situ lesions and 248 invasive cancers to investigate the relationship between its expression and various clinicopathological factors. Id-1 expression was significantly higher in invasive ductal carcinoma than in in situ ductal carcinoma or other invasive cancer subtypes (P=0.029 and 0.006, respectively). We also examined the association between Id-1 expression and tumor angiogenesis by measuring microvessel densities (MVD). Regarding the endothelial cells of microvessels showed negative or very weak Id-1 expression, Id-1 overexpression was found to be significantly related to MVD (P=0.014). Furthermore, Id-1 overexpression was found to be significantly associated with higher MVD in the ER-negative and node-involved subgroups of breast cancer (P=0.040 and 0.046, respectively). These data indicate that Id-1 overexpression is significantly associated with tumor angiogenesis, especially in the ER-negative and node-positive subtypes of invasive breast cancer. Thus, Id-1 presents a possible therapeutic antitumor target molecule in ER-negative and node-positive breast cancer.


Asunto(s)
Neoplasias de la Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Proteína 1 Inhibidora de la Diferenciación/metabolismo , Ganglios Linfáticos/patología , Neovascularización Patológica/metabolismo , Receptores de Estrógenos/metabolismo , Adenocarcinoma/irrigación sanguínea , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Neoplasias de la Mama/irrigación sanguínea , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/irrigación sanguínea , Carcinoma Ductal de Mama/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Técnicas para Inmunoenzimas , Microcirculación , Persona de Mediana Edad , Invasividad Neoplásica/patología , Estadificación de Neoplasias , Neoplasias Ductales, Lobulillares y Medulares/irrigación sanguínea , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/patología , Pronóstico , Receptores de Progesterona/metabolismo , Estudios Retrospectivos , Tasa de Supervivencia
6.
Clin Cancer Res ; 11(2 Pt 1): 520-8, 2005 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-15701836

RESUMEN

PURPOSE: The loss of Wnt-5a, a G-protein-coupled receptor ligand, or Syk, an intracellular kinase, has in separate studies been associated with poor prognosis of breast cancer patients. Both proteins are involved in cell adhesion, a key event in epithelial cancer metastasis. Here, we have investigated whether Syk is part of the Wnt-5a/discoidin domain receptor-1 (DDR1) signaling pathway and if a signaling interaction of these proteins is important for breast cancer-specific survival. EXPERIMENTAL DESIGN: The signaling interactions between Wnt-5a/DDR1 and Syk were addressed in mammary cell lines. Their mRNA and protein levels and the respective clinical correlates were investigated in 94 cases of primary breast cancer. RESULTS: The expression of Wnt-5a and Syk correlated in four of five tumor cell lines. However, despite a constitutive association between Syk and the Wnt-5a-dependent adhesion receptor DDR1, we found no evidence of a Wnt-5a/DDR1-mediated activation of Syk. Instead, beta(1) integrins initiate the adhesion-induced activation of Syk. In tumors from breast cancer patients, the protein expression of Wnt-5a and Syk were differently regulated at the translational and transcriptional level, respectively. Analysis of breast cancer-specific survival revealed that the presence of Wnt-5a and Syk in primary tumors has good predictive value for a favorable outcome. Intriguingly, a simultaneous loss of both proteins did not reduce survival more than loss of either. CONCLUSIONS: Despite the difference in regulation of Wnt-5a and Syk protein expression and their lack of signaling interaction, our clinical data indicate that a favorable prognosis in breast cancer requires the expression and signaling activity of both.


Asunto(s)
Neoplasias de la Mama/metabolismo , Precursores Enzimáticos/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Transducción de Señal , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Adhesión Celular/fisiología , Receptor con Dominio Discoidina 1 , Células Epiteliales/metabolismo , Humanos , Cadenas beta de Integrinas/farmacología , Péptidos y Proteínas de Señalización Intracelular , Invasividad Neoplásica/patología , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/mortalidad , Neoplasias Ductales, Lobulillares y Medulares/patología , Biosíntesis de Proteínas , Tasa de Supervivencia , Quinasa Syk , Transcripción Genética , Células Tumorales Cultivadas , Proteínas Wnt , Proteína Wnt-5a
7.
Clin Cancer Res ; 11(6): 2222-8, 2005 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-15788670

RESUMEN

PURPOSE: RON and MET belong to a subfamily of tyrosine kinase receptors. They both can induce invasive growth, including migration, cell dissociation, and matrix invasion. Cross-linking experiments show that RON and MET form a noncovalent complex on the cell surface and cooperate in intracellular signaling. We wanted to examine the clinical significance of RON and MET expression patterns in node-negative breast cancer. EXPERIMENTAL DESIGN: We studied the protein expressions of RON and MET in five breast cancer cell lines and a homogeneous cohort of 103 T(1-2)N(0)M(0) breast carcinoma patients, including 52 patients with distant metastases and 51 patients with no evidence of disease after at least a 10-year follow-up. RESULTS: Both HCC1937 and MDA-MB-231 cancer cell lines co-overexpressed RON and MET. The MCF-7 cell line did not express RON or MET. In multiple logistic regression analysis, RON expression (odds ratio, 2.6; P = 0.05) and MET expression (odds ratio, 4.7; P = 0.009) were independent predictors of distant relapse. RON+/MET+ and RON-/MET+ tumors resulted in a large risk increase for 10-year disease-free survival after adjusting for tumor size, histologic grade, estrogen receptor, bcl-2, HER-2/neu, and p53 status by multivariate Cox analysis (risk ratio, 5.3; P = 0.001 and risk ratio, 3.76; P = 0.005). The 10-year disease-free survival was 79.3% in patients with RON-/MET- tumors, was only 11.8% in patients with RON+/MET+ tumors, and was 43.9% and 55.6% in patients with RON-/MET+ and RON+/MET- tumors. CONCLUSIONS: Co-expression of RON and MET seems to signify an aggressive phenotype in node-negative breast cancer patients.


Asunto(s)
Neoplasias de la Mama/metabolismo , Ganglios Linfáticos/patología , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptores de Factores de Crecimiento/metabolismo , Adulto , Anciano , Neoplasias de la Mama/patología , Estudios de Cohortes , Femenino , Factor de Crecimiento de Hepatocito/metabolismo , Humanos , Persona de Mediana Edad , Invasividad Neoplásica/patología , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/secundario , Pronóstico , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Proto-Oncogénicas c-met , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Tasa de Supervivencia , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/metabolismo
8.
Oncogene ; 21(36): 5619-30, 2002 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-12165861

RESUMEN

The three human TACC genes encode a family of proteins that are suspected to play a role in carcinogenesis. Their function is not precisely known; a Xenopus TACC protein called Maskin is involved in translational control, while the Drosophila D-TACC associates with microtubules and centrosomes. We have characterized the human TACC1 gene and its products. The TACC1 gene is located in region p12 of chromosome 8; its mRNA is ubiquitously expressed and encodes a protein with an apparent molecular mass of 125 kDa, which is cytoplasmic and mainly perinuclear. We show that TACC1 mRNA gene expression is down-regulated in various types of tumors. Using immunohistochemistry of tumor tissue-microarrays and sections, we confirm that the level of TACC1 protein is down-regulated in breast cancer. Finally, using the two-hybrid screen in yeast, GST pull-downs and co-immunoprecipitations, we identified two potential binding partners for TACC1, LSM7 and SmG. They constitute a conserved subfamily of Sm-like small proteins that associate with U6 snRNPs and play a role in several aspects of mRNA processing. We speculate that down-regulation of TACC1 may alter the control of mRNA homeostasis in polarized cells and participates in the oncogenic processes.


Asunto(s)
Neoplasias de la Mama/genética , Proteínas Fetales , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/genética , Proteínas Nucleares , ARN Mensajero/metabolismo , Northern Blotting , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Cartilla de ADN/química , Regulación hacia Abajo , Femenino , Técnica del Anticuerpo Fluorescente , Glutatión Transferasa/metabolismo , Humanos , Immunoblotting , Proteínas de la Membrana/metabolismo , Proteínas Asociadas a Microtúbulos/genética , Persona de Mediana Edad , Proteínas de Neoplasias/genética , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/patología , Análisis de Secuencia por Matrices de Oligonucleótidos , Fragmentos de Péptidos/inmunología , Reacción en Cadena de la Polimerasa , Ribonucleoproteínas Nucleares Pequeñas/metabolismo , Saccharomyces cerevisiae , Fracciones Subcelulares , Células Tumorales Cultivadas/citología , Técnicas del Sistema de Dos Híbridos
9.
J Clin Oncol ; 21(23): 4306-13, 2003 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-14645419

RESUMEN

PURPOSE: To test the hypothesis that prognostic information in breast cancer may be derived from an accurate assessment of epithelial cell cycle entry, as indicated by expression of minichromosome maintenance (MCM) proteins. MATERIALS AND METHODS: We used immunohistochemistry to examine the distribution of Mcm-2 in breast tissue. Power calculations based on a pilot study of 67 whole tissue sections led to selection of an independent 347-core breast carcinoma tissue microarray validation set. We tested for associations between Mcm-2 (and Ki-67) labeling index (LI) and various clinicopathologic parameters. RESULTS: Mcm-2 was expressed more frequently than the standard proliferation marker Ki-67 in whole tissue sections of normal breast (P =.0003) and breast carcinoma (P <.0001). In 221 assessable cores of invasive carcinoma, the Mcm-2 LI showed a positive association with tumor size (P =.002), mitotic index (P <.0001), histologic grade (P <.0001), and the Nottingham Prognostic Index (NPI) score (P <.0001). Using a cutoff value of 50%, Mcm-2 LI was associated with overall survival (P =.0007), disease-free interval (P =.0002), and with the development of regional recurrence (P =.011) and distant metastases (P =.0016). Cox regression analysis suggested that the Mcm-2 LI is a strong prognostic factor in breast cancer that is independent and superior to histologic grade, lymph node stage, and Ki-67 LI, but not the NPI score. CONCLUSION: Mcm-2 may be of utility as a prognostic marker to refine the prediction of outcome in breast cancer, for example when combined with parameters currently used in the NPI.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Adulto , Anciano , Neoplasias de la Mama/patología , Replicación del ADN , Progresión de la Enfermedad , Femenino , Humanos , Técnicas para Inmunoenzimas , Antígeno Ki-67/metabolismo , Persona de Mediana Edad , Componente 2 del Complejo de Mantenimiento de Minicromosoma , Invasividad Neoplásica/diagnóstico , Invasividad Neoplásica/patología , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Neoplasias Ductales, Lobulillares y Medulares/diagnóstico , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/patología , Proyectos Piloto , Premenopausia , Pronóstico
10.
Clin Cancer Res ; 8(3): 811-6, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11895913

RESUMEN

PURPOSE: The purpose was to evaluate the utility of some bcl-2 family proteins fas and fasL as predictive indicators for chemotherapy response in advanced breast cancer. EXPERIMENTAL DESIGN: Between October 1994 and October 1997, 283 patients with advanced breast cancer were included in a multicenter randomized study comparing docetaxel (D) to sequential methotrexate and 5-fluorouracil (MF) after anthracycline failure. The response rates (complete response + partial response) were 42 and 21% in the D and MF arms, respectively (P < 0.001). In 126 patients, histological blocks of primary tumors were available for immunohistochemical analysis of bax, bcl-2, bcl-xL, bag-1, fas and fasL. RESULTS: Of the investigated factors, bag-1 correlated positively with bax, bcl-2, and fasL, and fasL correlated positively with fas and bax. None of these apoptosis-related factors was associated with a response to chemotherapy either in the whole patient population or in the D or MF arms. Interestingly, low bcl-2 expression was associated with shorter time to progression (P = 0.02) and shorter overall survival (OS; P = 0.001). High fasL expression showed a trend toward shorter OS. In multivariate backwards stepwise Cox analysis, in which histological grade and estrogen receptor status (ER) were also included, bcl-2 (P = 0.01) and fasL (P = 0.005) remained highly significantly associated with OS, whereas histological grade and ER lost their significance. CONCLUSIONS: None of the investigated apoptosis-related factors of primary tumor could predict the later response to either D or MF treatment. However, fasL and bcl-2 were strong prognostic factors. Patients who had tumors with high fasL and low bcl-2 expression had the shortest OS.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/metabolismo , Proteínas Portadoras/metabolismo , Glicoproteínas de Membrana/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Receptor fas/metabolismo , Adolescente , Adulto , Anciano , Antibióticos Antineoplásicos/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Proteínas de Unión al ADN , Resistencia a Antineoplásicos , Proteína Ligando Fas , Femenino , Fluorouracilo/administración & dosificación , Humanos , Técnicas para Inmunoenzimas , Metotrexato/administración & dosificación , Persona de Mediana Edad , Neoplasias Ductales, Lobulillares y Medulares/tratamiento farmacológico , Neoplasias Ductales, Lobulillares y Medulares/patología , Pronóstico , Proteínas Proto-Oncogénicas/metabolismo , Tasa de Supervivencia , Factores de Transcripción , Proteína X Asociada a bcl-2 , Proteína bcl-X
11.
Cancer Gene Ther ; 8(7): 469-72, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11498767

RESUMEN

Calcitonin (CT), the major secretory product of the C cell, is also expressed in C-cell-derived neoplasia. To investigate the role of the CT gene regulatory sequence in tissue-specific gene expression, the genes coding for the herpes simplex virus thymidine kinase (HSVtk) and for the enhanced green fluorescent protein (EGFP) regulated by the CT promoter (rAAV/CT266tkneo), the CT promoter/enhancer element (rAAV/CTenhtkneo), or the cytomegalovirus (CMV) promoter (rAAV/CMVtkneo) were transduced by recombinant adenoassociated viral (AAV) vectors into the medullary thyroid carcinoma (MTC) cell lines TT and hMTC and into HeLa cells as controls. In TT cell lines and hMTC cell lines transiently infected by the rAAV/CT266tkneo viruses, a significant increase in (3)H ganciclovir uptake was observed. Upon ganciclovir treatment, TT cells infected by rAAV/CT266tkneo revealed a significant growth inhibition, which was less tissue-specific because HeLa cells were also affected by these particles (74.5%). In contrast, a minor but more tissue-specific growth inhibition (33.6%) was observed for TT cells after transient infection with the rAAV/CTenhtkneo particles. Employing EGFP controlled by CMV promoter and the individual CT regulatory sequences for transduction by rAAV particles, similar results were obtained indicating that both the CT promoter and enhancer element are required for tissue-specific gene expression in MTC.


Asunto(s)
Calcitonina/biosíntesis , Dependovirus/genética , Regulación Neoplásica de la Expresión Génica , Técnicas de Transferencia de Gen , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Neoplasias de la Tiroides/metabolismo , Separación Celular , Elementos de Facilitación Genéticos , Citometría de Flujo , Vectores Genéticos , Proteínas Fluorescentes Verdes , Células HeLa , Humanos , Proteínas Luminiscentes/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/genética , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas , Simplexvirus/genética , Neoplasias de la Tiroides/genética , Factores de Tiempo , Transcripción Genética , Transfección , Células Tumorales Cultivadas
12.
Int J Oncol ; 24(5): 1197-204, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15067342

RESUMEN

Our purpose was to determine the respective prognostic significance of CD105 and CD31 immunoexpression in node negative patients with breast carcinoma, since angiogenesis induces blood borne metastases and death in carcinomas. CD105 (endoglin) has been reported as expressed by activated endothelial cells and consequently should better reflect neoangiogenesis in malignant tumors. Comparison of CD31 and CD105 immunocytochemical expression was undertaken in a series of 905 breast carcinomas. Results were compared to patients' long-term (median = 11.3 years) outcome. Univariate (Kaplan-Meier) analysis showed that the number of CD105+ microvessels (cut-off 15 vessels) correlated significantly with poor overall survival (p=0.001). This correlation was less significant in node negative patients (p=0.035). The number of CD31+ microvessels (cut-off 25 vessels) similarly correlated with poor survival (p=0.032) but not in the subgroup of node negative patients. Marked CD105 expression also correlated with a high risk for metastasis in all patients (p=0.0002) and in the subset of node negative patients (p=0.001). Similarly metastasis risk in node negative patients correlated with marked CD31 immunocytochemical expression (p=0.02). Multivariate analysis (Cox model) identified CD105, but not CD31 immunoexpression, as an independent prognostic indicator. Our results suggest that: i) in breast carcinomas, immunoselection of microvessels containing activated CD105 labelled endothelial cells is endowed with a stronger prognostic significance, as compared to CD31 vessels labelling; ii) the CD105 immunoexpression may be considered as a potential tool for selecting node negative patients with a poorer outcome and higher metastasis risk; iii) in these patients specific antiangiogenic therapy targeted by anti-CD105 conjugates can be further developed.


Asunto(s)
Neoplasias de la Mama/irrigación sanguínea , Neoplasias Ductales, Lobulillares y Medulares/irrigación sanguínea , Neovascularización Patológica/metabolismo , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Molécula 1 de Adhesión Celular Vascular/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Antígenos CD , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/metabolismo , Endoglina , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Técnicas para Inmunoenzimas , Ganglios Linfáticos/patología , Metástasis Linfática , Microcirculación , Neoplasias Ductales, Lobulillares y Medulares/diagnóstico , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Neovascularización Patológica/patología , Valor Predictivo de las Pruebas , Pronóstico , Receptores de Superficie Celular , Factores de Riesgo , Resultado del Tratamiento
13.
Int J Oncol ; 20(4): 717-21, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11894115

RESUMEN

Angiogenesis is intimately related to the growth and progression of tumours and must be induced to facilitate growth beyond a minimum size. It has been implicated in the development of metastases and survival in breast carcinoma. VEGF is a cytokine that plays an important role in angiogenesis. Its expression is increased in solid tumours during induction of angiogenesis and it has been implicated as a prognostic marker in patients with node negative breast carcinoma. We studied VEGF expression, in a series of patients with node positive breast carcinoma and examined histopathological parameters of the tumour and the prognostic value of VEGF expression. Specimens from 108 cases of node positive breast cancer were stained for VEGF using an antibody suitable for use on formalin fixed tissue. VEGF staining was cytoplasmic and was scored by intensity and the percent positive cells. Patients with positive VEGF staining (n=48) were compared with patients with negative VEGF staining (n=60). Demographic criteria were similar in both groups. Only one (12%) patient with lobular carcinoma and one (14%) patient with medullary carcinoma expressed VEGF compared with 46 (49%) patients with ductal carcinoma (NOS). DCIS was present in 60 tumours. There was a strong correlation between staining in DCIS and the adjacent invasive tumours. There was no significant association between VEGF staining and T stage, tumour size or the number of positive lymph nodes. VEGF expression had no prognostic significance either for disease-free or overall survival in patients with node positive disease. This study failed to support a role for VEGF as a prognostic marker in patients with node positive breast carcinoma.


Asunto(s)
Neoplasias de la Mama/metabolismo , Factores de Crecimiento Endotelial/metabolismo , Linfocinas/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Adenocarcinoma/terapia , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Carcinoma Intraductal no Infiltrante/metabolismo , Carcinoma Intraductal no Infiltrante/patología , Carcinoma Intraductal no Infiltrante/terapia , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Técnicas para Inmunoenzimas , Ganglios Linfáticos/patología , Persona de Mediana Edad , Invasividad Neoplásica , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/patología , Neoplasias Ductales, Lobulillares y Medulares/terapia , Pronóstico , Receptores de Estrógenos/metabolismo , Tasa de Supervivencia , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
14.
Oncol Rep ; 12(4): 755-9, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15375496

RESUMEN

Our aim was to study the role of oxidant and nitric oxide (NO)-derived damage in human breast carcinomas by studying the expression of nitrotyrosine in tumor tissue. To elucidate whether nitrotyrosine levels associate with NO synthesis and have an effect on antioxidative enzyme response or angiogenesis, we also studied the expression of all three nitric oxide synthases (NOS), manganese superoxide dismutase (MnSOD), catalase and vascular endothelial growth factor (VEGF) in the tumors. A large set of breast cancer samples in microarray blocks were stained with antibodies to nitrotyrosine, iNOS, eNOS, nNOS, MnSOD, catalase and VEGF. Nitrotyrosine expression was seen in 56% of the cases. There was a close relationship between the expression of nitrotyrosine and all three NOS isoforms (for all p<0.0005), catalase (p<0.0005) and MnSOD (p=0.043), in addition enlarged tumor size was in association with high nitrotyrosine (p=0.046), eNOS (p=0.005) and VEGF (p=0.046) levels. Our findings suggest that NO-derived oxidative damage takes place and its level associates to NOS synthesis in human breast cancer. The current results also imply the attempt of cells to hedge against effects of NO by increasing their MnSOD and catalase expression.


Asunto(s)
Neoplasias de la Mama/metabolismo , Depuradores de Radicales Libres/farmacología , Óxido Nítrico/metabolismo , Oxidantes/farmacología , Estrés Oxidativo , Tirosina/análogos & derivados , Adenocarcinoma Mucinoso/metabolismo , Adenocarcinoma Mucinoso/patología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/patología , Carcinoma Papilar , Catalasa/metabolismo , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/patología , Óxido Nítrico/farmacología , Óxido Nítrico Sintasa/metabolismo , Oxidación-Reducción , Isoformas de Proteínas , Superóxido Dismutasa/metabolismo , Tirosina/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
15.
Int J Oncol ; 41(2): 611-20, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22581300

RESUMEN

Docetaxel is one of the most commonly used chemotherapeutic agents in breast cancer. To avert from significant toxicities with no clinical benefit, identification of predictive markers for response is one of the most important unsolved clinical needs. Therefore, the potential associations of RASSF1A hypermethylation and response to docetaxel-based chemotherapy were evaluated, and the underlying mechanism was studied. The expression of RASSF1A in breast cancer cell lines and tissues of normal breast, ductal carcinoma in situ (DCIS), and breast cancer (n=45) was analyzed by immunohistochemistry and western blot analysis. Immunohistochemical staining showed that the expression of RASSF1A was frequently lost in primary breast cancers and human breast cancer cell lines, while normal breast tissues or DCIS displayed moderate to strong expression. Furthermore, quantitative methylation analysis of the RASSF1A promoter region in 45 primary breast cancers revealed that RASSF1A was frequently methylated in primary breast cancers (≥20% methylation in 53% of the patients), and prospective analysis in patients with locally advanced or recurrent breast cancer showed that the mean level of methylation of RASSF1A was significantly higher in patients who did not respond to docetaxel-based chemotherapy (30.6±8.5%) than patients with partial or complete response (20.1±11.2%, p=0.042). Finally, in vitro studies showed that RASSF1A had cooperative activity in suppression of cancer cell growth and proliferation by enhancing docetaxel-induced cell cycle arrest. Our results suggest that hypermethylated RASSF1A is an important modulating factor for the efficacy of docetaxel-based chemotherapy in breast cancer.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Metilación de ADN , Neoplasias Ductales, Lobulillares y Medulares/tratamiento farmacológico , Regiones Promotoras Genéticas , Taxoides/farmacología , Moduladores de Tubulina/farmacología , Proteínas Supresoras de Tumor/genética , Adulto , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Secuencia de Bases , Neoplasias de la Mama/metabolismo , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Proliferación Celular , Docetaxel , Regulación hacia Abajo , Epigénesis Genética , Femenino , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Humanos , Modelos Logísticos , Análisis Multivariante , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Análisis de Secuencia de ADN , Taxoides/uso terapéutico , Moduladores de Tubulina/uso terapéutico , Proteínas Supresoras de Tumor/metabolismo
16.
Histopathology ; 51(1): 33-9, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17542993

RESUMEN

AIMS: There is considerable evidence to link cyclooxygenase (COX)-2 to the development of cancer. The aim of this study was to assess COX-2 expression and its subcellular localization in lobular in situ neoplasia (LIN) of the breast and to verify differences in COX-2 expression between different grades of lesions according to the Tavassoli classification. METHODS AND RESULTS: We analysed the expression of COX-2 protein by immunohistochemistry in tissue samples of 51 LIN lesions classified into three grades according to the Tavassoli classification. COX-2 immunostaining was observed in 78.4% of LIN samples and showed a prevalent membranous rather than cytoplasmic pattern. COX-2 was expressed in 16/17 (94.1%) LIN1, 22/25 (88%) LIN2 and 2/9 (22.2%) LIN3. As regards COX-2 expression, a statistically significant difference was found between LIN1 and LIN3 (P = 0.001) and between LIN2 and LIN3 (P =0.001). No difference was found between LIN1 and LIN2. Moreover, a significant negative correlation was found between LIN grade and COX-2 expression (P < 0.0001). CONCLUSIONS: COX-2 is highly expressed in LIN, supporting a role for this protein in the early stage of breast carcinogenesis, representing the rationale for using COX-2 selective inhibitors in the earliest stages of breast cancer.


Asunto(s)
Neoplasias de la Mama/metabolismo , Carcinoma Intraductal no Infiltrante/metabolismo , Ciclooxigenasa 2/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Mama/metabolismo , Mama/patología , Neoplasias de la Mama/clasificación , Neoplasias de la Mama/patología , Carcinoma Intraductal no Infiltrante/clasificación , Carcinoma Intraductal no Infiltrante/patología , Ciclooxigenasa 2/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Persona de Mediana Edad , Neoplasias Ductales, Lobulillares y Medulares/clasificación , Neoplasias Ductales, Lobulillares y Medulares/patología
17.
Breast Cancer ; 14(4): 381-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17986803

RESUMEN

BACKGROUND: Lymphatic vessel invasion (LVI) has been conventionally assessed on hematoxylin-eosin (HE) stained sections, but this assessment tends to be subjective. The aim of this study is to investigate the significance of LVI in invasive breast cancers, primarily using immunohistochemical lymphatic endothelial markers. METHODS: We studied 69 invasive breast carcinoma cases. Using D2-40 and podoplanin, we investigated the distribution of lymphatic vessels around the tumor and LVI, and they were compared with the HE sections. The correlation between LVI, lymph node metastasis and disease free survival (DFS) was also investigated. RESULTS: Lymphatic vessels were most frequently seen outside the tumor (86%), whereas lymphatic vessels were not seen in the central zone of the tumor. LVI was found in 22 cases, of which nineteen was seen in the peripheral zone (87%). For both HE and lymphatic markers, the rates of mild LVI tended to be high. The concordance rate between D2-40 and podoplanin was 94.2% (65/69). LVI assessed on HE sections was corresponded to 54/69 cases (78.2%) using either D2-40 or podoplanin. There were 25 axillary lymph node positive cases. Lymph node metastasis significantly correlated with LVI assessed by HE section, but did not correlate with LVI assessed by the lymphatic markers. The tumor recurred in 19 cases during the mean follow-up period of 47.5 months. Disease free survival was significantly better for LVI negative cases on HE analysis, and LVI negative or mildly positive by any staining procedure. CONCLUSION: The lymphatic endothelium markers, D2-40 and podoplanin, are very useful for detecting LVI, but careful examination by routine HE sections may be enough for routine practice. Moderate or marked degree of LVI may be of value to predict survival.


Asunto(s)
Adenocarcinoma Mucinoso/patología , Neoplasias de la Mama/patología , Endotelio Linfático/patología , Ganglios Linfáticos/patología , Vasos Linfáticos/patología , Neoplasias Ductales, Lobulillares y Medulares/patología , Adenocarcinoma Mucinoso/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/metabolismo , Anticuerpos Monoclonales de Origen Murino , Biomarcadores de Tumor , Neoplasias de la Mama/metabolismo , Endotelio Linfático/metabolismo , Femenino , Humanos , Técnicas para Inmunoenzimas , Ganglios Linfáticos/metabolismo , Metástasis Linfática , Vasos Linfáticos/metabolismo , Glicoproteínas de Membrana/metabolismo , Persona de Mediana Edad , Invasividad Neoplásica/diagnóstico , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Pronóstico
18.
Cancer ; 103(11): 2241-51, 2005 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-15844176

RESUMEN

BACKGROUND: The objective of this study was to assess hormone receptor status as an independent predictor of survival in a population-based cohort of women with breast carcinoma who were followed for up to 11 years. METHODS: Since 1990, the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program has collected data on hormone receptor status among patients with breast carcinoma. In a cohort of 205,736 women with breast carcinoma age > or = 20 years at diagnosis who were entered into the SEER data base between 1990 and 2000, the authors analyzed the association of hormone receptor status with year of diagnosis, patient age, disease stage, tumor histology, tumor grade, race/ethnicity, and metropolitan/statewide residence areas. Kaplan-Meier survival curves were compared according to hormone receptor status, and Cox proportional-hazards regression models were used to assess the association of hormone receptor status with breast carcinoma-specific and all-cause mortality controlling for age, disease stage, tumor grade, tumor histology, race/ethnicity, and SEER region. RESULTS: Women who had tumors that were positive for both estrogen and progesterone hormone receptors had significantly better survival than other women with breast carcinoma in the overall cohort, within each stage, and in the younger and older age groups, although the survival advantage was greater among women age < or = 50 years than among older women. Hormone receptor status was associated with mortality even when patient age, disease stage, tumor grade, tumor histology, race/ethnicity, and metropolitan/statewide residence areas were taken into account. CONCLUSIONS: Hormone receptor status was identified as an independent predictor of outcome in women with breast carcinoma. Data from clinical trials with long follow-up may shed light on whether and how the benefit of hormonal and other treatment varies with hormone receptor status.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/mortalidad , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica/patología , Estadificación de Neoplasias , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/mortalidad , Programa de VERF , Tasa de Supervivencia
19.
Br J Cancer ; 93(9): 1046-52, 2005 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-16175185

RESUMEN

Breast cancer is a heterogeneous disease, though little is known about some of its rarer forms, including certain histologic types. Using Surveillance, Epidemiology, and End Results Program data on 135 157 invasive breast cancer cases diagnosed from 1992 to 2001, relationships between nine histologic types of breast cancer and various tumour characteristics were assessed. Among women aged 50-89 years at diagnosis, lobular and ductal/lobular carcinoma cases were more likely to be diagnosed with stage III/IV, > or =5.0 cm, and node-positive tumours compared to ductal carcinoma cases. Mucinous, comedo, tubular, and medullary carcinomas were less likely to present at an advanced stage. Lobular, ductal/lobular, mucinous, tubular, and papillary carcinomas were less likely, and comedo, medullary, and inflammatory carcinomas were more likely to be oestrogen receptor (ER) negative/progesterone receptor (PR) negative and high grade (notably, 68.2% of medullary carcinomas were ER-/PR- vs 19.3% of ductal carcinomas). In general, similar differences were observed among women diagnosed at age 30-49 years. Inflammatory carcinomas are associated with more aggressive tumour phenotypes, and mucinous, tubular, and papillary tumours are associated with less aggressive phenotypes. The histologic types of breast cancer studied here differ greatly in their clinical presentations, and the differences in their hormone receptor profiles and grades point to their likely different aetiologies.


Asunto(s)
Adenocarcinoma Mucinoso/patología , Adenocarcinoma/patología , Neoplasias de la Mama/patología , Carcinoma Intraductal no Infiltrante/patología , Carcinoma Papilar/patología , Neoplasias Ductales, Lobulillares y Medulares/patología , Adenocarcinoma/metabolismo , Adenocarcinoma Mucinoso/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/metabolismo , Carcinoma Intraductal no Infiltrante/metabolismo , Carcinoma Papilar/metabolismo , Femenino , Humanos , Ganglios Linfáticos/patología , Persona de Mediana Edad , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Programa de VERF
20.
Breast Cancer Res Treat ; 81(3): 195-207, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14620915

RESUMEN

Tumor MUC1 expression as well as levels of MUC1, MUC1 circulating immune complexes (MUC1-CIC) and free antibodies against MUC1 (IgG and IgM-MUC1) were evaluated in 70 breast cancer patients with different stages of disease. Controls included: 135 serum samples from healthy women, normal mammary tissue samples (n = 7) and benign breast disease specimens (n = 6). In all assays, pre- and post-vaccination serum samples from breast cancer patients belonging to a vaccination protocol developed at the Memorial Sloan Kettering Cancer Center (New York, USA) were included as controls. Serum MUC1 was measured through Cancer Associated Serum Antigen test and CA15-3 test. Employing ELISA, MUC1-CIC-IgG/M were measured with either C595 or SM3 monoclonal antibodies (MAb) as catchers and also free antibodies against MUC1 (IgG and IgM) using 100mer peptide as catcher. Employing multivariate statistical analysis, results were correlated with age, tumor type, stage of disease and grade of differentiation. By quantitative immunohistochemistry using three anti-MUC1 core protein MAbs (C595, HMFG2 and SM3), tumor MUC1 was detected in 60/70 (86%) breast cancer specimens which reacted with at least one of these MAbs. High MUCI serum levels were detected in 14/67 (21%); IgG and IgM anti-MUC1 antibodies were found elevated in 32 and 14%, respectively, while IgG-MUC1-CIC-measured with C595 in 42% and IgM-MUC1-CIC in 54%; finally, SM3 was positive in 43 and 18%, respectively. Results of these studies demonstrate that in a group of breast cancer patients, MUC1 was detected both in tissue specimens as well as free in serum samples; furthermore, MUC1 can also circulate complexed with IgG and IgM antibodies; thus an accurate measurement should include free and complexed forms. On the other hand, immunohistochemical studies on breast cancer tissues may contribute to reveal different MUC1 glycoforms.


Asunto(s)
Adenocarcinoma/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/metabolismo , Mucina-1/metabolismo , Neoplasias Ductales, Lobulillares y Medulares/metabolismo , Adenocarcinoma/sangre , Adulto , Anciano , Anciano de 80 o más Años , Complejo Antígeno-Anticuerpo/inmunología , Antígenos de Neoplasias/inmunología , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/inmunología , Neoplasias de la Mama/sangre , Femenino , Humanos , Inmunoglobulina G/análisis , Inmunoglobulina M/análisis , Persona de Mediana Edad , Mucina-1/sangre , Mucina-1/inmunología , Neoplasias Ductales, Lobulillares y Medulares/sangre , Distribución Tisular
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