First Author | Wu MX | Year | 2003 |
Journal | Apoptosis | Volume | 8 |
Issue | 1 | Pages | 11-8 |
PubMed ID | 12510147 | Mgi Jnum | J:81101 |
Mgi Id | MGI:2448050 | Doi | 10.1023/a:1021688600370 |
Citation | Wu MX (2003) Roles of the stress-induced gene IEX-1 in regulation of cell death and oncogenesis. Apoptosis 8(1):11-18 |
abstractText | In response to changes in the external environment cells must initiate a coordinated program of gene expression for them to adapt. IEX-1 (immediate early response gene X-1) is precisely regulated by multiple transcription factors among which p53, NF-kappaB/rel, Sp1 and c-Myc play central roles, to ensure rapid and transient expression of IEX-1 in cells under a variety of stress conditions. Overexpression of IEX-1 renders some cells sensitive to apoptosis and accelerates cell cycle progression, but reduces proliferation of other cells, whereas disruption of IEX-1 expression is associated with decreases in both apoptosis and cell cycle progression. In sharp contrast to in vitro studies, in vivo constitutive expression of IEX-1 prevents activated T cells but not B cells from apoptosis, as shown using IEX-1-transgenic mice that target IEX-1 expression specifically to lymphocytes driven by the E&mgr; enhancer. The animals developed a lupus-like disease and subsequently a high incidence of T cell lymphomas when they aged, due to insufficient apoptosis of T cells. These varied effects of IEX-1 on cell death and cell cycle progression in a cell-context dependent fashion implicate that IEX-1 is involved in more than one signaling pathway, understanding of which will certainly improve our knowledge with respect to cancer biology, cell death and cell cycle regulation. |