Apoptosis deficiency defines prognostic subgroups and therapy resistance in a xenograft model of pediatric BCP-ALL

We previously demonstrated that intact cytochrome c related activation of caspases in pediatric acute leukemia is only found in patients with favorable outcome. In a NOD/SCID/huALL model rapid engraftment (short time to leukemia, TTLshort) determines poor patient outcome. In xenograft leukemia samples intact apoptosis signaling was only found in the TTLlong group, whereas it was absent in TTLshort. In addition, a significant positive correlation of TTL and cytochrome c release indicated prolonged leukemia engraftment to be due to proficient apoptosis signaling. Leukemia bearing mice were treated according to ind…