The transcription factor Ets-1 regulates the expression of several angiogenic and extracellular matrix remodeling factors, and might be implicated in disease progression of breast cancer. In the present study, the prognostic value of Ets-1 expression was assessed by quantitative realtime fluorescence RT -PCR in 123 sporadic primary breast cancer samples of patients with a median followup time of 62 months. Ets-1 expression levels correlated significantly with VEGF and PAI-1 in the same tissue. In univariate (P=0.0011) and multivariate (P=0.005) analyses, Ets-1 expression showed significant prognostic value for relapse-free survival. Ets-1 is a strong, independent predictor of poor prognosis in breast cancer. This seems -at least in part -to be attributable to its role in transcriptional regulation of factors involved in angiogenesis (VEGF), and extracellular matrix remodeling (PAI-1).

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Activation of the sympathetic nervous system inhibits insulin-stimulated glucose uptake. However, the underlying mechanisms are incompletely understood. Therefore, we studied the effects of catecholamines on insulin-stimulated glucose uptake and insulin-stimulated translocation of GLUT4 to the plasma membrane in 3T3-L1 adipocytes. We found that epinephrine (1 microM) nearly halved insulin-stimulated 2-deoxyglucose uptake. The beta-adrenoceptor antagonist propranolol (0.3 microM) completely antagonized the inhibitory effect of epinephrine on insulin-stimulated glucose uptake, whereas the alpha-adrenoceptor antagonist phentolamine (10 microM) had no effect. When norepinephrine was used instead of epinephrine, the results were identical. None of the individual selective beta-adrenoceptor antagonists (1 microM, beta(1): metoprolol, beta(2): ICI-118551, beta(3): SR-59230A) could counteract the inhibitory effect of epinephrine. Combination of ICI-118551 and SR-59230A, as well as combination of all three selective beta-adrenoceptor antagonists, abolished the effect of epinephrine on insulin-stimulated glucose uptake. After differential centrifugation, we measured the amount of GLUT1 and GLUT4 in the plasma membrane and in intracellular vesicles by means of Western blotting. Both epinephrine and norepinephrine reduced insulin-stimulated GLUT4 translocation to the plasma membrane. These results show that beta-adrenergic (but not alpha-adrenergic) stimulation inhibits insulin-induced glucose uptake in 3T3-L1 adipocytes, most likely via the beta(2)- and beta(3)-adrenoceptor by interfering with GLUT4 translocation from intracellular vesicles to the plasma membrane.

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Expression of human chorionic gonadotrophin (hCG) is associated with trophoblastic, testicular and other malignancies such as bladder, pancreatic, cervical, breast and prostate cancer. In the prostate, however, hCG expression, associated with neuroendocrine cells, is also found in normal tissue. Of the six highly homologous genes that all encode the -subunit of hCG, the 7 gene is reportedly the only gene expressed in several non-transformed tissues. The 3, 5 and 8 genes would be variably expressed in malignant tissue and placenta, but not in normal tissue. To assess to what extent this expression difference can also be found in the prostate, we compared the levels of the different hCG transcripts in concurrent normal and cancerous prostate tissues obtained from 17 patients. To this end, we developed a Taqman real-time fluorescent RT-PCR assay for hCG , and a quantitative assay specific for the 3, 5 and 8 genes, modified from the molecular beacon principle. This latter assay proved highly specific and capable of reliably distinguishing between these hCG transcripts that differ in only one nucleotide. Surprisingly, median expression levels of hCG were lower in prostate cancer when compared with normal tissue from the same patient. In contrast, hCG 3, 5 and 8 transcripts were found in normal tissue and did not differ in prostate cancer, arguing against a specific role of these transcripts in the development of prostate cancer.