Apoptosis induction by iron deprivation in tumor cells: role of mitochondria and caspases

0191629 - UMG-J 20033137 RIV GB eng C - Conference Paper (international conference)
Kovář, Jan - Koc, Michal - Štýbrová, Hana - Truksa, Jaroslav - Ehrlichová, Marie
Apoptosis induction by iron deprivation in tumor cells: role of mitochondria and caspases.
Abstracts of the 25th Meeting of the European Study Group for Cell Proliferation (ESGCP). UK: Blackwell Publishing, 2002, s. 2.
[Meeting of the European Study Group for Cell Proliferation /25./. Reims (FR), 24.10.2002-27.10.2002]
Institutional research plan: CEZ:AV0Z5052915
Keywords : apoptosis induction * caspase activation * Bax translocation
Subject RIV: EB - Genetics ; Molecular Biology

Iron deprivation specifically induces apoptosis in some tumor cells while other tumor cells are resistant. We have shown previously that the p53 pathway, including p53 activation and subsequent regulation of the expression of relevant genes of the bcl-2 family such as bax and bcl-2, is not involved in apoptosis induction by iron deprivation. In the present study we compared the activity of caspase-3 and caspase-9 in sensitive (38C13) versus resistant (EL4) cells under control and iron-depriving conditions. Iron deprivation resulted in a significant increase of the caspase-3 activity in sensitive but not in resistant cells. Similarly, we detected caspase-9 activation under iron deprivation in sensitive but not in resistant cells. We also compared the distribution of some proteins of the Bcl-2 family in sensitive versus resistant cells under control and iron-depriving conditions. Confocal microscopy revealed that iron deprivation resulted in Bax protein translocation from the cytosol to mitochondria in sensitive but not in resistant cells. We suggest that the mitochondrial pathway including subsequent caspase-9 activation and caspase-3 activation could be involved in apoptosis induction by iron deprivation. Studies concerning the release of cytochrome c, Apaf-1 and AIF from mitochondria due to iron deprivation are under way.
Permanent Link: http://hdl.handle.net/11104/0087367