Involvement of the TGF-β and mTOR/p70S6Kinase pathways in the transformation process induced by v-ErbA

✍ Scribed by S. Gonin-Giraud; C. Bresson-Mazet; O. Gandrillon

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 807 KB
• Volume: 32
• Category: Article
• ISSN: 0145-2126
• DOI: 10.1016/j.leukres.2008.05.010

✦ Synopsis

v-ErbA is the oncogenic form of TR␣/c-ErbA which transforms chicken erythrocytic progenitors by blocking differentiation. The oncogenic property of v-ErbA has been correlated with its ability to antagonize ligand-dependent gene activation by TR␣/c-ErbA and retinoic acid receptors. Nevertheless, its cytoplasmic retention suggests that v-ErbA could interfere with intracellular signaling pathways. We demonstrate that only the transforming form of v-ErbA confers to chicken erythroid progenitors a TGF-␤ independency and induces an activation of the mTOR/p70S6K pathway. In these cells, TGF-␤ and mTOR/p70S6K pathways regulate the expression of a known target gene of v-ErbA, band3. This is the first demonstration that v-ErbA is able to modulate specifically some signaling pathways leading to changes in the expression level of a gene involved in transformation.