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Introduction Baseline karyotype at diagnosis remains the pivotal determinant of outcome in patients with acute myeloid leukemia (AML). The Medical Research Council (MRC) prognostic model is currently the benchmark for risk assessment in this patient population. However, the prognostic role of the complete spectrum of chromosomal abnormalities in AML patients undergoing allogeneic hematopoietic stem cell transplantation (allo-SCT) is currently unknown. Furthermore, their significance in conjunction with FLT3-ITD status has not been addressed thus far. Methods Using the Acute Leukemia Working Party/European Society for Blood and Marrow Transplantation multicenter database a retrospective analysis was performed to assess the clinical outcomes of AML patients undergoing allo-SCT with respect to specific recurring cytogenetic abnormalities complemented with FLT3-ITD status. We analyzed a cohort consisting of 8558 adult AML patients who underwent allo-SCT in first remission from either a matched sibling or a matched unrelated donor in 2006-2016. Results Patients with inv(3)(q21q26)/t(3;3)(q21;q26), del(5q), monosomy 7, chromosome 17p abnormalities, t(10;11)(p11-14;q13-23), t(6;11)(q27;q23), as well as those patients with a monosomal or complex karyotype experienced significantly inferior leukemia-free survival (LFS) compared to patients with a normal karyotype. Del (9q), trisomy 14, and loss of chromosome X were associated with improved LFS rates. A novel prognostic model delineating 5 distinct groups incorporating cytogenetic complexity and FLT3-ITD status was constructed with significant prognostic implications. Conclusion Our analysis endorses the prognostic significance of the MRC predictive model in patients undergoing allo-SCT in CR1 with some specific modifications. Furthermore, consideration of FLT3-ITD and karyotypic complexity improved the projective capacity of the MRC model in transplanted patients. [ABSTRACT FROM AUTHOR]

Although having promising anti-myeloma properties, the pan-histone deacetylase inhibitor (HDACi) panobinostat lacks therapeutic activity as a single agent. The aim of the current study was to elucidate the mechanisms underlying multiple myeloma (MM) resistance to panobinostat monotherapy and to define strategies to overcome it. Sensitivity of MM cell lines and primary CD138+ cells from MM patients to panobinostat correlated with reduced expression of the chemokine receptor CXCR4, whereas overexpression of CXCR4 in MM cell lines increased their resistance to panobinostat. Decreased sensitivity to HDACi was associated with reversible G0/G1 cell growth arrest while response was characterized by apoptotic cell death. Analysis of intra-cellular signaling mediators revealed the pro-survival mTOR pathway to be regulated by CXCR4 overexpression. Combining panobinostat with mTOR inhibitor everolimus abrogated the resistance to HDACi and induced synergistic cell death. The combination of panobinostat/everolimus resulted in sustained DNA damage and irreversible suppression of proliferation accompanied by robust apoptosis. Gene expression analysis revealed distinct genetic profiles of single versus combined agent exposure. Whereas panobinostat increased the expression of the cell cycle inhibitor p21, co-treatment with everolimus abrogated the increase in p21 and synergistically downregulated the expression of DNA repair genes and mitotic checkpoint regulators. Importantly, the combination of panobinostat with everolimus effectively targeted CXCR4-expressing resistant MM cells in vivo in the BM niche. In summary, our results uncover the mechanism responsible for the strong synergistic anti-MM activity of dual HDAC and mTOR inhibition and provide the rationale for a novel potential therapeutic approach to treat MM. [ABSTRACT FROM AUTHOR]

Background Allogeneic haematopoietic stem cell transplantation (alloHSCT) is considered a standard treatment for patients with Philadelphia chromosome–positive acute lymphoblastic leukaemia (Ph+ ALL) achieving complete remission after induction containing tyrosine kinase inhibitors (TKIs). Methods We retrospectively compared results of myeloablative alloHSCT from either matched sibling donor (MSD) or unrelated donor (URD) with autologous (auto) HSCT for adults with Ph+ ALL in molecular remission, treated between 2007 and 2014. Results In univariate analysis, the incidence of relapse at 2 years was 47% after autoHSCT, 28% after MSD-HSCT and 19% after URD-HSCT ( P = 0.0002). Respective rates of non-relapse mortality were 2%, 18%, and 22% ( P = 0.001). The probabilities of leukaemia-free survival were 52%, 55% and 60% ( P = 0.69), while overall survival rates were 70%, 70% and 69% ( P = 0.58), respectively. In multivariate analysis, there was a trend towards increased risk of overall mortality after MSD-HSCT (hazard ratio [HR], 1.5, P = 0.12) and URD-HSCT (HR, 1.6, P = 0.08) when referred to autoHSCT. The use of total body irradiation (TBI)–based regimens was associated with reduced risk of relapse (HR, 0.65, P = 0.02) and overall mortality (HR, 0.67, P = 0.01). Conclusion In the era of TKIs, outcomes of myeloablative autoHSCT and alloHSCT for patients with Ph+ ALL in first molecular remission are comparable. Therefore, autoHSCT appears to be an attractive treatment option potentially allowing for circumvention of alloHSCT sequelae. Irrespective of the type of donor, TBI-based regimens should be considered the preferable type of conditioning for Ph+ ALL. [ABSTRACT FROM AUTHOR]