Dalbavancin and Selected Comparison Agents Tested Against Indicated Gram-positive Isolates in European Medical Centers (Italy): Results from the DECIDE Program

tetracycline (96.4%) and gentamicin (99.3%). Staphylococci included MRSA (35.7%) and MR-CoNS (68.4%); and MRSA isolates were resistant to levofloxacin (96%) and erythromycin (74%). All clindamycin-susceptible SA had inducible resistance. Dalbavancin (MIC90; 0.047mg/L) was 10-fold more potent than vancomycin (MIC90; 0.5mg/L) against BHS. Erythromycin susceptibility was 82% with a 25% inducible clindamycin resistance. Conclusions: The DECIDE study demonstrated in UK and Ireland that dalbavancin has excellent activity and was more potent when directly compared to vancomycin. Dalbavancin was active against all MRSA, although the current susceptibility profiles for other antimicrobial classes tested were of great concern, particularly inducible clindamycin resistance (100%). Monitoring dalbavancin activity should be continued as this newer long-acting agent is introduced into EU clinical practice

Triorganotin(IV) derivatives of 7-amino-2-(methylthio)[1,2,4]triazolo [1,5-a]pyrimidine-6-carboxylic acid. Synthesis, spectroscopic characterization, in vitro antimicrobial activity and X-ray crystallography

Triorganotin(IV) complexes of the 7-amino-2-(methylthio)[1,2,4]triazolo[1,5-a]pyrimidine-6-carboxylic acid (HL), Me3SnL(H2O), (1), [n-Bu3SnL]2(H2O), (2), Ph3SnL(MeOH), (3), were synthesized by reacting the amino acid with organotin(IV) hydroxides or oxides in refluxing methanol. The complexes have been characterized by elemental analysis, 1H, 13C and 119Sn NMR, IR, Raman and 119Sn Mössbauer spectroscopic techniques. Single crystal X-ray diffraction data were obtained for compounds (2) and (3). Ph3SnL(MeOH) presents a trigonal bipyramidal structure with the organic groups on the equatorial plane and the axial positions occupied by a ligand molecule, coordinated to tin through the carboxylate, and a solvent molecule, MeOH. A similar structure is proposed for Me3SnL(H2O) on the basis of analytical and spectroscopic data. The tributyltin(IV) derivative, [n-Bu3SnL]2(H2O), is characterized by two different tin sites with similar tbp geometry featured by butyl groups on the equatorial plane. Sn(1) and Sn(2) atoms are axially bridged by a ligand molecule binding through the N(4) and the carboxylate group; the two coordination spheres are saturated by another ligand molecule, binding the metal through the carboxylate group, and a water molecule, respectively. Antimicrobial tests on compounds 1 and 2 showed in vitro activity against Gram-positive bacteria

Notch2 Increases the Resistance to Venetoclax-Induced Apoptosis in Chronic Lymphocytic Leukemia B Cells by Inducing Mcl-1

Chronic lymphocytic leukemia (CLL) has experienced a clinical revolution—thanks to the discovery of crucial pathogenic mechanisms. CLL is still an incurable disease due to intrinsic or acquired resistance of the leukemic clone. Venetoclax is a Bcl-2 inhibitor with a marked activity in CLL, but emerging patterns of resistance are being described. We hypothesize that intrinsic features of CLL cells may contribute to drive mechanisms of resistance to venetoclax. We analyzed the expression of Interferon Regulatory Factor 4 (IRF4), Notch2, and Mcl-1 in a cohort of CLL patients. We evaluated CLL cell viability after genetic and pharmaceutical modulation of Notch2 expression in patients harboring trisomy 12. We tested venetoclax in trisomy 12 CLL cells either silenced or not for Notch2 expression or in combination with an inhibitor of Mcl-1, AMG-176. Trisomy 12 CLL cells were characterized by low expression of IRF4 associated with high levels of Notch2 and Mcl-1. Notch2 and Mcl-1 expression determined protection of CLL cells from spontaneous and drug-induced apoptosis. Considering the involvement of Mcl-1 in venetoclax resistance, our data demonstrated a contribution of high levels of Notch2 and Mcl-1 in a reduced response to venetoclax in CLL cells carrying trisomy 12. Furthermore, reduction of Mcl-1 expression by silencing Notch2 or by treatment with AMG-176 was able to restore the response of CLL cells to venetoclax. The expression of Notch2 identifies a subset of CLL patients, mainly harboring trisomy 12, characterized by high levels of Mcl-1. This biological mechanism may compromise an effective response to venetoclax

Monocytic population in chronic lymphocytic leukemia shows altered composition and deregulation of genes involved in phagocytosis and inflammation

Macrophages reside in tissues infiltrated by chronic lymphocytic leukemia B-cells and the extent of infiltration is associated with adverse prognostic factors. Blood monocyte population was studied by flow cytometry and whole-genome microarrays. A mixed lymphocyte reaction was performed to evaluate T cell proliferation in contact with monocytes from patients and normal donors. Migration and gene modulation in normal monocytes treated with leukemia were also evaluated. Chronic lymphocytic leukemia patients showed an increase in the absolute number of monocytes compared to normal controls (792+/-86 cells/mL vs. 485+/-46 cells/mL, p=0.003). Higher number of nonclassical CD14+CD16++ and Tie-2 expressing monocytes (TEMs) was also detected in patients. Furthermore, we performed a gene expression analysis of monocytes in chronic lymphocytic leukemia patients, showing up-regulation of RAP1GAP and down-regulation of tubulins and CDC42EP3, which would be expected to result in impairment in phagocytosis. We also detected gene alterations such as the down-regulation of PTGR2, a reductase able to inactivate the prostaglandin E2, indicating an immunosuppressive activity. Accordingly, T cell proliferation was inhibited in contact with monocytes from patients compared to normal controls. Finally, normal monocytes in vitro increased migration and up-regulated CD16, RAP1GAP, IL-10, IL-8, MMP9 and down-regulated PTGR2 in response to leukemic cells or conditioned media. In conclusion, altered composition and deregulation of genes involved in phagocytosis and inflammation were found in blood monocytes obtained from chronic lymphocytic leukemia patients, suggesting that leukemia-mediated 'education' of immune elements may also include the establishment of a skewed phenotype in monocyte/macrophage population

Busulfan or Treosulfan Conditioning Platform for Allogeneic Stem Cell Transplantation in Patients Aged >60 y with Acute Myeloid Leukemia/Myelodysplastic Syndrome: A Subanalysis of the GITMO AlloEld Study

Background. The conditioning regimens with different alkylators at different doses can influence the outcome of allogeneic stem cell transplantation (SCT), but conclusive data are missing. Methods. With the aim to analyze real-life allogeneic SCTs performed in Italy between 2006 and 2017 in elderly patients (aged >60 y) with acute myeloid leukemia or myelodysplastic syndrome, we collected 780 first transplants data. For analysis purposes, patients were grouped according to the type of alkylator included in the conditioning (busulfan [BU]-based; n = 618; 79%; treosulfan [TREO]-based; n=162; 21%). Results. No significant differences were observed in nonrelapse mortality, cumulative incidence of relapse, and overall survival, although in the TREO-based group, we observed a greater proportion of elderly patients (P < 0.001); more active diseases at the time of SCT (P < 0.001); a higher prevalence of patients with either hematopoietic cell transplantation-comorbidity index ≥3 (P < 0.001) or a good Karnofsky performance status (P = 0.025); increased use of peripheral blood stem cells as graft sources (P < 0.001); and greater use of reduced intensity conditioning regimens (P = 0.013) and of haploidentical donors (P < 0.001). Moreover, the 2-y cumulative incidence of relapse with myeloablative doses of BU was significantly lower than that registered with reduced intensity conditioning (21% versus 31%; P = 0.0003). This was not observed in the TREO-based group. Conclusions. Despite a higher number of risk factors in the TREO group, no significant differences were observed in nonrelapse mortality, cumulative incidence of relapse, and overall survival according to the type of alkylator, suggesting that TREO has no advantage over BU in terms of efficacy and toxicity in acute myeloid leukemia and myelodysplastic syndrome