RESUMEN
BACKGROUND: Dilated cardiomyopathy (DCM) is a disorder characterised by dilation and impaired contractility of the left or both ventricles. This multifactorial disease has a strong genetic component with familial occurrence. A number of genes have been associated with idiopathic DCM (IDCM) including beta-1 (b1-AR) and beta-2 (b2-AR) adrenergic receptors. b1-AR and b2-AR are G-coupled proteins which play an important role in the regulation of heart rate and cardiac contractility. The beta-adrenergic receptor pathway is altered in heart failure. Recent studies have discovered functionally relevant and common polymorphisms in both b1-AR and b2-AR. AIM: We investigated the frequency of the b1-AR (Ser49Gly, Arg389Gly) and b2-AR (Arg16Gly, Gln27Glu, Thr164Ile) polymorphisms in patients with IDCM in comparison to controls in the Polish population. METHODS: We used a case-control study design comparing a series of consecutive, unrelated 97 IDCM patients with 105 healthy blood donors. Polymorphisms were determined by polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP). RESULTS: There was no significant difference in relation to genotype distribution and allele frequencies of any analysed b1-AR and b2-AR polymorphisms between IDCM patients and controls. The analysis of polymorphism associations did not reveal a higher frequency of coexisting b2-AR Gly16Gln27, Gly16Glu27 and Arg16Gln27 genotypes alone or in combination with the b1-AR Arg389 allele in IDCM. CONCLUSION: Our data showed that the studied beta-adrenergic receptor polymorphisms did not seem to play a significant role in IDCM in the Polish population.
Asunto(s)
Cardiomiopatía Dilatada/genética , Polimorfismo de Longitud del Fragmento de Restricción , Receptores Adrenérgicos beta 1/genética , Receptores Adrenérgicos beta 2/genética , Función Ventricular Izquierda/genética , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Polonia , Medición de RiesgoRESUMEN
OBJECTIVE: Wnt family of secreted-type glycoproteins plays key role in carcinogenesis and embryogenesis. Signals of Wnts are transduced through seven-transmembrane-type Wnt receptors encoded by Frizzled (Fzd) genes to the beta-catenin-Tcf pathway, the c-Jun-N-terminal kinase (JNK) pathway or the Ca(2+)-releasing pathway. Aberrant activation of the Wnt/beta-catenin signaling pathway is associated with a variety of human cancers. In human breast cancer, evidence of beta-catenin accumulation implies that the canonical Wnt signaling pathway is active in over 50% of carcinomas. RESULTS: We found that in breast cancer cells overexpressing Wnt-1 siRNA anti-Wnt-1 induced apoptosis and caused changes in downstream proteins levels. Among treated cells there were 71% apoptotic cells in comparison to cells treated with scrambled siRNA (6%) and control cells (6%) after 48 h (p < 0.01). METHODS: To examine if Wnt-1 signal is essential for cancer cell survival, we investigated the effect of Wnt-1 gene silencing in triggering of apoptosis in MCF-7 breast cancer cell line. Light microscopy, viability/cytotoxicity tests, flow cytometry, real-time PCR and western blotting were used for evaluation of the morphological features of cell death, percentage of apoptotic cells, Wnt-1 mRNA and protein level. CONCLUSION: Our results significantly indicate that anti-Wnt-1 siRNA inhibits Wnt-1 signaling, inducing apoptosis in human breast cancer MCF-7 cells and thus may serve as a potential anti-cancer drug.
Asunto(s)
Apoptosis/genética , Neoplasias de la Mama/patología , Regulación Neoplásica de la Expresión Génica , Silenciador del Gen , Proteína Wnt1/metabolismo , Apoptosis/fisiología , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Supervivencia Celular/genética , Femenino , Humanos , Proteínas/análisis , Proteínas/metabolismo , ARN Mensajero/análisis , ARN Mensajero/metabolismo , ARN Interferente Pequeño/farmacología , Transducción de Señal/genética , Transducción de Señal/fisiología , Proteína Wnt1/genética , beta Catenina/biosíntesis , beta Catenina/genéticaRESUMEN
BACKGROUND INFORMATION: The nuclear gene hSUV3 (human SUV3) encodes an ATP-dependent DNA/RNA helicase. In the yeast Saccharomyces cerevisiae the orthologous Suv3 protein is localized in mitochondria, and is a subunit of the degradosome complex which regulates RNA surveillance and turnover. In contrast, the functions of human SUV3 are not known to date. RESULTS: In the present study, we show that a fraction of human SUV3 helicase is localized in the nucleus. Using small interfering RNA gene silencing in HeLa cells, we demonstrate that down-regulation of hSUV3 results in cell cycle perturbations and in apoptosis, which is both AIF- and caspase-dependent, and proceeds with the induction of p53. CONCLUSIONS: In addition to its mitochondrial localization, human SUV3 plays an important role in the nucleus and is probably involved in chromatin maintenance.
