Fanconi anemia genes act to suppress a cross-linker-inducible p53-independent apoptosis pathway in lymphoblastoid cell lines
FA Kruyt, LM Dijkmans, TK van den Berg, H Joenje - 1996 - ashpublications.org
FA Kruyt, LM Dijkmans, TK van den Berg, H Joenje
1996•ashpublications.orgHypersensitivity to cross-linking agents such as mitomycin C (MMC) is characteristic of cells
from patients suffering from the inherited bone marrow failure syndrome. Fanconi anemia
(FA). Here, we link MMC hypersensitivity of Epstein-Barr virus (EBV)-immortalized FA
lymphoblasts to a high susceptibility for apoptosis and p53 activation. In MMC-treated FA
cells belonging to complementation group C (FA-C), apoptosis followed cell cycle arrest in
the G2 phase. In stably transfected FA-C cells, plasmid-driven expression of the wild-type …
from patients suffering from the inherited bone marrow failure syndrome. Fanconi anemia
(FA). Here, we link MMC hypersensitivity of Epstein-Barr virus (EBV)-immortalized FA
lymphoblasts to a high susceptibility for apoptosis and p53 activation. In MMC-treated FA
cells belonging to complementation group C (FA-C), apoptosis followed cell cycle arrest in
the G2 phase. In stably transfected FA-C cells, plasmid-driven expression of the wild-type …
Hypersensitivity to cross-linking agents such as mitomycin C (MMC) is characteristic of cells from patients suffering from the inherited bone marrow failure syndrome. Fanconi anemia (FA). Here, we link MMC hypersensitivity of Epstein-Barr virus (EBV)-immortalized FA lymphoblasts to a high susceptibility for apoptosis and p53 activation. In MMC-treated FA cells belonging to complementation group C (FA-C), apoptosis followed cell cycle arrest in the G2 phase. In stably transfected FA-C cells, plasmid-driven expression of the wild-type cytoplasmic FAC protein relieved MMC-dependent G2 arrest and suppressed p53 activation. However, in both FA and non-FA lymphoblasts, p53 seemed not to be instrumental in the induction of MMC-dependent apoptosis, since overexpression of a dominant-negative p53 mutant failed to affect cell survival. In addition, no differences in the level of Bcl-2 expression, an inhibitor of apoptosis, were detected between FA and non- FA cells either in the absence or presence of MMC. Our findings suggest that FAC and the other putative FA gene products may function in a yet to be identified p53-independent apoptosis pathway.
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