In total, 17 pediatric patients with hematologic malignancies (n ¼ 14) and Fanconi anemia (FA) (n ¼ 3) underwent haploidentical SCT with T-cell depletion. The patients were conditioned with reduced-intensity regimens, and CYA was used for GVHD prophylaxis. Successful engraftment occurred in 16 patients (94%). One patient failed to achieve a primary engraftment. Another patient rejected the first SCT after 10 weeks and had a successful second transplant. Of all engrafted patients, only one developed severe acute GVHD. Ten patients were alive at a median follow-up of 18 months (range, 5-62 months). The 5-years' OS was 53.8%. The three patients with FA are currently well with full-donor chimerism at 16, 6 and 5 months post transplant, respectively. The OS of 14 patients with high-risk hematologic malignancies was 47.6%. Three patients died as a result of post transplant leukemia relapse. CMV infection, GVHD and organ injury were other causes of mortality. Haploidentical SCT was found to be an alternative feasible treatment in Uruguay for patients who need allogenic transplantation but lack an HLA-identical family donor. It should be considered as an early option in FA patients before transformation or significant exposure to blood products.

We describe the in vitro studies to demonstrate the activity and drug combinability of ABT-737 against MLL rearranged leukemia cells. In addition, identification of the molecular changes that occur in the presence of ABT-737 provides information regarding effective target validation and target modulation analyses in future clinical trials.

Interference with the molecular mechanisms that generate tumor supportive niches in the bone microenvironment is a rational approach to inhibit the growth of hematological malignancies. However, the advancement of knowledge in this area has been slowed down by the lack of in vitro models to facilitate the screening of potential candidate agents. The rare cases of acute lymphoblastic leukemia (ALL) in children presenting with extensive bone involvement may represent an exaggerated form of some aspects of the normal tumor-bone interactions. Thus, these cases can provide insight into processes that are otherwise challenging to uncover. The authors describe the case of a 6-year-old child who presented with severe osteopenia that resolved at the time of leukemic remission. Compared to control sera, serum taken at disease presentation contained increased levels of a group of osteolytic cytokines and was effective in activating preosteoclast cells in culture. Based on these findings, the authors describe an experimental model to identify agents that would interfere with leukemia mediated osteolytic process.