Elective coiling of unruptured intracranial aneurysms is associated with fewer deaths and perioperative complications compared with elective clipping. The trend of hospital use of the coiling procedures has increased during recent years.

The transcriptional activity of estrogen receptor-␣ is controlled by coregulators. MTA1 (metastasis-associated protein 1) represses estrogen receptor-␣-driven transcription by recruiting histone deacetylases (HDACs) to the estrogen response element containing target gene chromatin in breast cancer cells. Using a yeast twohybrid screen with the MTA1 C-terminal domain as bait, we identified MAT1 (mé nage á trois 1) as an MTA1-binding protein. MAT1 is an assembly/targeting factor for cyclin-dependent kinase-activating kinase (CAK), which has been shown to functionally interact with general transcriptional factor TFIIH, a known inducer of ER transactivation. We show that estrogen signaling promotes nuclear translocation of MAT1 and that MTA1 interacts with MAT1 both in vitro and in vivo. The eukaryotic genome is compacted with histone and other proteins to form chromatin, which consists of repeating units of nucleosome (1, 2). Formation of nucleosomes and higher order chromatin structures can render the DNA inaccessible to transcription factors and complexes. For transcription factors to access DNA, the repressive chromatin structure needs to be remodeled. Dynamic alterations in the chromatin structure can facilitate or suppress the access of the transcription factors to nucleosomal DNA, leading to transcriptional regulation. One way to achieve this is through alterations in chromatin remodeling factors or in the acetylation state of nucleosomal histones (3-5). Acetylation of core histones occurs at lysine residues on the N-terminal tails of the histones, thus neutralizing the positive charge of the histone tails and decreasing their affinity for DNA. Hyperacetylated chromatin is generally associated with transcription activation, whereas hypoacetylated chromatin is associated with transcription repression (3-6).A number of recent studies have raised the possibility of a close connection between HDACs 1 and cancer. Because HDACmediated deacetylation of nucleosomal histones is known to be associated with transcriptional repression of some genes, it is being proposed that the deregulation of recruitment of HDACcontaining repressor complex to specific target promoters could serve as a potential mechanism by which these enzymes contribute to tumorigenesis. For example, MTA1 (metastasis-associated protein 1) represses estrogen receptor-␣ (ER)-driven transcription by recruiting HDAC to the ER response element (ERE)-containing target gene chromatin in breast cancer cells (7). The NuRD-70 polypeptide of nucleosome remodeling/ HDAC complex is identical to that of the MTA1 (8 -11). The MTA1 gene was initially identified by differential expression in rat mammary adenocarcinoma metastatic cells, and its expression has been shown to correlate well with the metastatic potential of several human cell lines and tumors (12).To better understand the cellular functions of MTA1 in breast cancer cells, we performed a yeast two-hybrid screen to clone MTA1-interacting proteins. One of several isolates was identified as MAT1 (ménage á troi...

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The risk of developing CIN is low among patients with acute stroke who undergo emergency endovascular treatment. Treatment of acute stroke should be performed irrespective of Cr levels.