Insulin-like growth factors (IGFs) are potent mitogens for breast cancer cells. Although IGF-binding proteins (IGFBPs) are known to regulate access of IGFs to IGF receptors, their precise biological ...actions are poorly defined. We observed that the potent antiestrogen ICI 182780 (ICI) increased IGFBP-5 mRNA by 2-3-fold in 9,10-dimethyl-1,2-benzanthracene-induced mammary tumors in vivo. In vitro studies showed that growth inhibition of MCF-7 human breast cancer cells induced by ICI was associated with increased transcription of the IGFBP-5 gene, increased IGFBP-5 mRNA abundance, and increased IGFBP-5 protein accumulation in the conditioned medium. Growth stimulation following estradiol exposure was associated with opposite effects. An IGFBP-5 antisense oligodeoxynucleotide significantly decreased IGFBP-5 accumulation in conditioned media and enhanced MCF-7 cell DNA synthesis. Furthermore, this antisense oligodeoxynucleotide attenuated both antiestrogen-induced IGFBP-5 accumulation and antiestrogen-induced growth inhibition. These data demonstrate that estradiol down-regulates and ICI up-regulates an autocrine IGFBP-5 growth inhibitory pathway in MCF-7 cells and suggest that IGFBP-5 plays a role in modulation of proliferation of breast cancers by estrogens and antiestrogens.
An antenna array devoted to the autonomous radio-detection of high energy cosmic rays is being deployed on the site of the 21 cm array radio telescope in XinJiang, China. Thanks in particular to the ...very good electromagnetic environment of this remote experimental site, self-triggering on extensive air showers induced by cosmic rays has been achieved with a small scale prototype of the foreseen antenna array. We give here a detailed description of the detector and present the first detection of extensive air showers with this prototype.
Doppler ultrasonic examination has been used as an indirect means of per-operative checking of sweat secretion after non surgical upper dorsal sympathectomy performed by percutaneous injection of hot ...saline into the upper dorsal sympathetic ganglions for the treatment of palmar hyperhydrosis. Their experience with pre, per and post-operative utilisation of Doppler effect in sixty cases has evidenced a full parallelism between the arterial vasodilation and the decrease in sweat secretion following the destruction of the sympathetic ganglions by hot saline. In the last series of thirty-five cases per-operative use of Doppler ultrasonic examination has spared them failures of the procedure. They consider Doppler ultrasonic examination as a precious help in classical open sympathectomy as well in their non surgical method.
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