Article

A microRNA component of the hypoxic response. Cell Death Differ

Molecular Oncology Research Institute, Tufts-New England Medical Center, Boston, MA 02111, USA.
Cell Death and Differentiation (Impact Factor: 8.39). 05/2008; 15(4):667-71. DOI: 10.1038/sj.cdd.4402310
Source: PubMed

ABSTRACT microRNAs participate in a wide variety of physiological and pathological cellular processes. Recent studies have established a link between a specific group of microRNAs and hypoxia, a key feature of the neoplastic microenvironment. A significant proportion of the hypoxia-regulated microRNAs (HRMs) are also overexpressed in human cancers, suggesting a role in tumorigenesis. Preliminary evidence suggests that they could affect important processes such as apoptosis, proliferation and angiogenesis. Several HRMs exhibit induction in response to HIF activation, thus extending its repertoire of targets beyond translated genes. In the present review, we discuss the emerging roles of HRMs in oxygen deprivation in cancer context.

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Available from: Mircea Ivan, Mar 05, 2014
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    • "Recent studies indicate that HIF-1 directly activates a number of hypoxia-responsive microRNAs (HRMs) such as miR-210 and miR-373 which are involved in the regulation of a variety of celland tissue-specific responses to hypoxia (Kulshreshtha et al., 2008; Crosby et al., 2009). Because HRMs are implicated in diverse physiological processes, we speculated that the effects of hypoxia on adrenal steroidogenesis may be mediated by certain HIF1- regulated miRNAs. "
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    • "A wide array of miRNAs have been linked to the transcriptional response to hypoxia. There is an extensive and growing list of miRNAs regulated by hypoxia, either positively or negatively , in different experimental settings (Kulshreshtha et al., 2008; Loscalzo, 2010; Bussolati et al., 2012; Du et al., 2012; Fang et al., 2012; Guo et al., 2012; Voellenkle et al., 2012). Other miRNAs are hypoxia-independent , but are capable of negatively regulating HIF; these include miR-107, miR-17-92 and miR-519c, whose expression is induced by p53, c-myc and the hepatocyte growth factor (HGF), respectively (Taguchi et al., 2008; Cha et al., 2010; Yamakuchi et al., 2010). "
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    • "In addition to post-transcriptional modification of HIF-1a/b by miRNAs, HIF-1 itself has been shown to regulate the expression of miRNAs (Galanis et al., 2008; Kulshreshtha et al., 2008) in dependence of oxygen availability (Kulshreshtha et al., 2007; Huang et al., 2009). It is likely that HIF-1 is a direct regulator of miRNA response to hypoxia in different cancer cell lines, because of the presence of putative HIF-1 binding sites, suggesting participation in tumorigenesis. "
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