RESUMEN
Recent studies have suggested that aneuploidy in malignant tumours could be a consequence of centrosome aberrations. Using immunofluorescence analysis with an antibody against gamma-tubulin and DNA image cytometry, we measured centrosome aberrations and DNA ploidy patterns in fine-needle aspiration biopsies (FNABs) of 58 breast lesions. Benign lesions did not show any centrosome aberrations. DNA diploid carcinomas showed a mean percentage of cells with centrosomal defects of 2.1%. The aneuploid invasive carcinomas could be divided into two subgroups by their significantly (P=0.0003) different percentage of cells with centrosome aberrations (2.0 and 10.3%, respectively) and their significantly (P=0.0003) different percentage of cells with nonmodal DNA content values determined by the Stemline Scatter Index (SSI), a measure of genomic instability. The percentage of cells with centrosome aberrations demonstrated a positive, linear correlation with the corresponding SSI (r=0.82, P<0.0001) and loss of tissue differentiation (r=0.78, P<0.0001). Our results indicate the percentage of cells with centrosome aberrations as being sufficient to divide the investigated tumours into three significantly different groups: benign lesions with no centrosomal aberrations, and two malignant tumour types with mean values of 2.1 and 9.6% of centrosomal defects, respectively. Together, these results demonstrate that centrosome aberrations correlate with genomic instability and loss of tissue differentiation. Furthermore, this study shows the feasibility of centrosomal analysis in FNAB of the breast and suggests centrosomal aberrations as possessing diagnostic and prognostic value.
Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Centrosoma/patología , ADN de Neoplasias/análisis , Inestabilidad Genómica , Adulto , Anciano , Anciano de 80 o más Años , Aneuploidia , Biopsia con Aguja Fina , Neoplasias de la Mama/clasificación , Técnica del Anticuerpo Fluorescente , Humanos , Procesamiento de Imagen Asistido por Computador , Persona de Mediana EdadRESUMEN
Squamous epithelial cancer in situ (CIS) of the upper aerodigestive tract is a histopathologically well-defined condition. There is yet no reliable way to predict whether a CIS lesion will progress to invasive cancer, remain stable or regress. In the search for markers able to foretell clinical outcome, we performed immunohistochemical staining with a polyclonal antibody against recombinant gamma 2 chain of laminin-5 in 33 laryngeal CIS lesions. All six CIS lesions which progressed to invasive cancer, within a follow-up time of 5 years, were laminin-5 positive (100%), whereas only 10 out of 27 lesions which did not progress were positive (37%) (p < 0.01). Our data showed that a positive laminin-5 laryngeal CIS lesion indicates a high risk for progression to invasive cancer.
Asunto(s)
Biomarcadores de Tumor/análisis , Carcinoma in Situ/patología , Carcinoma de Células Escamosas/patología , Moléculas de Adhesión Celular/análisis , Neoplasias Laríngeas/patología , Invasividad Neoplásica/diagnóstico , Proteínas de Neoplasias/análisis , Adulto , Anciano , Animales , Carcinoma in Situ/química , Carcinoma de Células Escamosas/química , Manejo de Caso , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/inmunología , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Técnicas para Inmunoenzimas , Neoplasias Laríngeas/química , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/inmunología , Pronóstico , Subunidades de Proteína , Conejos , Proteínas Recombinantes de Fusión/inmunología , Riesgo , KalininaRESUMEN
Signalling via the protein kinase Raf-MEK-ERK pathway is of major importance for transformation by oncogenes. To identify genes affected by inhibition of this pathway, c-JUN transformed rat fibroblasts were treated with a MEK1 inhibitor (PD98059) and subjected to two-dimensional gel electrophoresis after cell lysis. Gene products with expression influenced by MEK1 inhibition were determined by mass spectrometry of fragments from in-gel tryptic digestions. The expression of pirin, a nuclear factor I-interacting protein, was lowered after inhibition of MEK1. Western blot analysis revealed increased expression of pirin in RAS and c-JUN transformed cells in the absence of PD98059. Inhibition of MEK1 also led to reduced expression of alpha-enolase, phosphoglycerate kinase, elongation factor 2 and heterogeneous nuclear ribonucleoprotein A3, the latter two being detected as truncated proteins. In contrast, the level of ornithine aminotransferase was increased. We conclude that inhibition of MEK1 results in major alterations of protein expression in c-JUN transformed cells, suggesting that this pathway is important for oncogene-induced phenotypic changes.
Asunto(s)
Proteínas Portadoras/biosíntesis , Transformación Celular Neoplásica/genética , Fibroblastos/metabolismo , Genes jun , Genes ras , Quinasas de Proteína Quinasa Activadas por Mitógenos , Proteínas Quinasas Activadas por Mitógenos , Proteínas Nucleares/biosíntesis , Proteínas Serina-Treonina Quinasas/fisiología , Proteínas Tirosina Quinasas/fisiología , Transducción de Señal/genética , Animales , Proteínas Quinasas Dependientes de Calcio-Calmodulina/fisiología , Proteínas Portadoras/genética , Línea Celular Transformada , Dioxigenasas , Fibroblastos/efectos de los fármacos , Flavonoides/farmacología , Ribonucleoproteínas Nucleares Heterogéneas , MAP Quinasa Quinasa 1 , Espectrometría de Masas , Proteína Quinasa 1 Activada por Mitógenos , Proteína Quinasa 3 Activada por Mitógenos , Proteínas Nucleares/genética , Ornitina-Oxo-Ácido Transaminasa/biosíntesis , Ornitina-Oxo-Ácido Transaminasa/genética , Factor 2 de Elongación Peptídica , Factores de Elongación de Péptidos/biosíntesis , Factores de Elongación de Péptidos/genética , Fosfoglicerato Quinasa/biosíntesis , Fosfoglicerato Quinasa/genética , Fosfopiruvato Hidratasa/biosíntesis , Fosfopiruvato Hidratasa/genética , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-raf/fisiología , Ratas , Ribonucleoproteínas/biosíntesis , Ribonucleoproteínas/genética , TransfecciónRESUMEN
Increased urokinase plasminogen activator (u-PA) production is associated with tumor invasion and metastasis in several malignancies, including breast cancer. The mechanisms underlying constitutive u-PA expression are not well understood. We examined the relationship between the signal strength of the ERK pathway and the level of u-PA expression in the metastatic human breast cancer cell line MDA-MB-231. Treatment with the MEK1 inhibitor PD98059 resulted in decreased ERK1/2 phosphorylation and decreased u-PA mRNA and protein expression. Inhibition of ERK1/2 activity also led to decreased cell proliferation and to decreased cyclin D1 expression. Less than 5% of total ERK1/2 was phosphorylated in exponentially growing MDA-MB-231 cells, and ERK1/2 activity could be stimulated by okadaic acid. Okadaic acid did not stimulate u-PA expression, but induced strong expression of the cdk-inhibitor p21Cip1. These findings suggest that ERK1/2 signaling is tuned to a level which results in high u-PA expression and rapid cell proliferation.