ALBERT

Description: Introduction With standard intensive induction regimens, up to 80% of Acute Myeloid leukemia (AML) patients can achieve complete remission (CR). Several evidences demonstrated that the persistence of detectable disease (MRD) assessed with highly sensitive techniques such as Multicolor-Flow-Cytometry (MFC) and PCR based molecular analysis, retains a prognostic value among patients achieving morphological remission (Walter RB, 2015; Araki D et al, 2016, Zhou Y et al, 2016). The aim of the present study was to retrospectively evaluate the prognostic impact of MRD in a cohort of uniformly treated AML patients. One hundred and ten consecutive AML patients who had been treated in our center between January 2004 and December 2014 were retrospectively analyzed. All patients had received a fludarabine-containing induction (FLAI-5) and received second cycle and further consolidation therapy according to our published strategy (Guolo F, 2016). Median age was 47 years (range 17-61). Median follow up was 59 months. Patients features are summarized in Table I. MRD assessment was performed through 4-colour MFC analysis (MFC-MRD)and through WT1-gene expression analysis, as previously described (Guolo F, 2016). Three different MRD time-points (TP)were considered: TP1, after induction I; TP2, after induction II; TP3, after consolidation therapy for patients who did not undergo HSCT and at HSCT for patients who underwent HSCT. Relapse-free survival (RFS) was calculated from the time of diagnosis until last follow-up or documented leukemic relapse. CR rate after 1st and 2ndinduction was 82.7 and 85.5%, respectively, whereas 30 and 60 days mortality was 6.4% and 8.2%, respectively. Overall, patients showed MRD reduction from TP1 to TP2. Detailed MRD negativity rates are provided in table II. MRD clearance probability was significantly influenced only by ELN risk group and Karyotype (p

Description: Background: Acute Myeloid Leukemia (AML) is an incurable disease characterized by a highly unstable genome, resulting in large-scale changes at diagnosis, as well as further evolution contributing to disease progression. However, the mechanisms whereby tumor cells adapt to genomic instability are largely unknown, but recent observations have correlated these abnormalities with dysfunctional DNA damage repair (DDR) machinery. SIRT6 is an important regulator of cellular stress response and genomic integrity. Here we investigated the role of this NAD+ -dependent deacetylase in regulating ongoing DNA damage observed in AML patients. Methods: SIRT6 mRNA level was determined by RT-qPCR in AML patients (n=100) diagnosed at the Hematology Department of University of Genoa (Italy), compared with normal bone marrow derived CD34+ cells (n=5). Correlation studies with clinical and molecular characteristics of these patients were also performed. A panel of different AML cell lines and primary cells, both sensitive and resistant to conventional and novel anti-AML therapies, was used in the study. The anti-leukemic effect of DNA-damaging agents (DDAs) including idarubicin, Ara-C and fludarabine was evaluated in presence of SIRT6 depletion/inhibition by CTG assay and Annexin-V/propidium iodide staining. Mechanistic studies were performed with Western-blotting, lentivirus-mediated shRNAs and immunofluorescence assay. Analysis of DNA DSB repair was done using chromosomally integrated reporter constructs, followed by cytometer analysis. Results: AML patients were grouped into lower and higher SIRT6 expressers according to its median mRNA level. Patients with lower expression had a higher incidence of FLT3-ITD (p=0.034, Wilcoxon signed rank test). No significant association was observed with respect to mutations of NPM1, nor with WT1 and BAALC expression. SIRT6 expression correlated also with adverse clinical outcome in term of event free and overall survival (p=0.035 and p=0.025, respectively; unpaired t test). Based on these data, we evaluated SIRT6 role in biology of AML. We found higher SIRT6 protein level in AML cell lines carrying FLT3-ITD mutation (MOLM-14 and MV 4-11) compared to cell lines harboring other mutations (OCI-AML3, THP-1, KG, NB4, HL60, Nomo1 and U937). Targeting SIRT6 by specific shRNAs weakly reduced AML cell survival compared with control-scrambled cells, by impairing DNA repair efficiency. Indeed, a restricted effect of SIRT6 impairment on DNA damage proteins (H2AX, RAD51, 53BP1, RPA32) was measured. We next examined the therapeutic relevance of SIRT6 inhibition in AML by testing effects of its depletion in combination with genotoxic agents. Remarkably, SIRT6 depletion conferred increased sensitivity of AML cells to idarubicin, Ara-C and Fludarabine. Overall, enhancing genotoxic stress while concomitantly blocking DNA double-strand breaks (DSBs) repair response, may represents an innovative strategy to increase chemosensitivity of AML cells. Further mechanistic studies revealed that SIRT6 acts as a genome guardian in leukemia cells by binding DNA damage sites and activating DNA-PKcs and CtIP by deacetylation, which in turn promotes DNA repair. Conclusion: Genomic instability is present in all hematologic malignancies including AML. Strategies aimed to shift the balance towards high DNA damage and reduced DNA repair by SIRT6 inhibition can decrease AML growth and may benefit patients with otherwise unfavorable outcomes. Disclosures No relevant conflicts of interest to declare.

Description: BACKGROUND AND AIMS Allogeneic bone marrow transplantation (BMT) offers the greatest chance of cure for patients with high-risk acute myeloid leukemia (AML). Persistence of disease or high levels of pre BMT minimal residual disease (MRD) have been reported to predict relapse risk after BMT. WT1 expression levels and multicolor flow cytometry (MFC) are the most common tools to evaluate MRD. We recently reported that combining WT1 expression and MFC for MRD detection after induction therapy strongly impacts on relapse risk in AML. The aim of this study was to analyze the role of pre-BMT MRD assessment as predictor for the post-transplant relapse risk. MATERIALS AND METHODS We retrospectively analyzed the outcome of 253 consecutive AML patients receiving allo-BMT. Pre-BMT marrow samples were analysed for WT1 expression and MFC as MRD evaluation . Median age at transplant was 45 years. Disease phase was CR1 in 161, CR2 in 63, and CR3 in 29 patients. One hundred eighty-two received myeloablative conditioning, whereas 71 patients received reduced intensity conditioning. Median follow-up was 59 months (95% CI 46.2 - 71.8 months). Relapse-free survival (RFS) was calculated from the time of transplantation until last follow-up or documented leukemic relapse. Overall Survival (OS) was calculated from the time of transplantation until death by any cause or last follow-up. A positive MFC MRD was defined by the presence of no less than 25 clustered leukemic cells/105 total events (threshold of 2.5x10-4 residual leukemic cells) at four-color flow-cytometry. Real-time PCR for WT1 was performed on DNA Engine 2 (Opticon®, MJ Research®). WT1 copy number/Abl copy number 500x104 was used as cut-off value for abnormal WT1 expression. RESULTS Relapse occurred in 81 patients (32%). Three-year estimate of RFS was 63.7% (median not reached). The probability of relapse was significantly affected by disease status (first or subsequent CR, p

Description: Background Blastic plasmacytoid dendritic cell neoplasm (BPDCN) are a very rare group of diseases included by WHO 2016 classification among the myeloid neoplasms and usually display an aggressive course with dismal outcome. BPDCN are characterized by a recurrent phenotype (CD45low/CD34-/CD56+/CD4+/CD123+), in the absence of other lineage differentiation markers. Our group recently reported that a subset of patients diagnosed with AML with NPM1-mutation carrying co-expression of CD123, CD56 and CD4, a "BPDCN-like" phenotype, showed poor prognosis. The aim of the present study was to evaluate the incidence and the prognostic impact of BPDCN-like phenotype in a wider cohort of cytogenetically normal AML patients, irrespectively of NPM1-mutational status. Methods We retrospectively evaluated a cohort of 83 younger (age

Description: Background: The presence of FLT3 "internal tandem duplication" (FLT3-ITD) mutation is associated with poor prognosis in acute myeloid leukemia (AML). However, the concomitant presence of NPM1 mutation (NPM1-mut) partially overcomes the negative prognostic impact of FLT3-ITD, which is also modulated by FLT3-ITD/wild-type allelic ratio. NPM1 and FLT3 mutational status assessment is strongly recommended for risk stratificationat diagnosis by the last European Leukemia Net (ELN) guidelines. Aims: To investigate the efficacy of an intensive fludarabine-containing induction regimen (FLAI) for fit, de novo AML patients according to NPM1 and FLT3-ITD mutational status. Methods: One-hundred and sixteen consecutive AML patients, treated in 3 Hematology Italian centers from January 2008 to January 2018, were included in this analysis. Twenty five patients showed isolated FLT3-ITD, 39 concomitant FLT3-ITD and NPM1-mutation and 52 isolated NPM-1-mutation.Median age was 52 yrs (range: 18-65 years). All patients received fludarabine, high dose cytarabine-based induction (fludarabine 30 mg/sqm and ARA-C 2g/sqm ondays 1 to 5 plus idarubicin 10 mg/sqm on days 1-3-5). For patients achieving CR fludarabine was omitted on II induction course and idarubicin dose was increased to 12 mg/sqm. Before2017 patients with isolated FLT3-ITD mutation were scheduled to receive allogeneic bone marrow transplantation (BMT) in first complete remission regardless of allelic burden whereas after 2017 only patients with high allelic burden received BMT in 1st CR. Minimal residual disease was evaluated on marrow samples using multicolor flow-cytometry (MFC)or NPM1 expression levels. Negative MFC-MRD wasdefined by the presence of less than 25 clustered leukemic cells/105 total events (threshold of 0.025% residual leukemic cells, Minetto et. al, BJH 2019). NPM1mutation (NPM1-A, B and D) was measured using Muta Quant Kit Ipsogen from Qiagen. FLT3-ITD allelic burden was available in31/64 of FLT3-ITD patients. Results: Overall 60-days mortality was 4%. After two induction cycles, 101 patients achieved CR (87%). Thirty-three/101 (33%) CR patients underwent BMT in first CR. After a median follow up of 61 months, 3-year overall survival (OS) was 56.8% (median not reached). In univariate analysis OS duration was favorably affected by age

Description: BACKROUND: Hodgkin Lymphoma (HL) is characterized by a high degree of response to chemotherapy and an overall favorable outcome in responding patients. Despite the efficacy of first line therapy, however, about 30% of patients affected by HL eventually relapse or are refractory (R/R) to first or second line therapy followed by autologous hemopoietic stem cell transplantation (ASCT). Recently, the clinical application of immune checkpoint inhibitors (CI), in particular the PD-1 targeting antibody Nivolumab, has dramatically improved the prognosis of patients affected by advanced phase solid tumours. In HL, Nivolumab has shown good activity in the difficult setting of patients relapsing after ASCT; however, complete response (CR) rate was less than 20%. Many studies in the solid tumours field have shown that the efficacy of CI is strictly related to the host degree of immune competence, which is greatly impaired in heavily pre-treated HL patients who received ASCT. Therefore, there is a strong rationale in enhancing the activity of the CI with the co-infusion of autologous lymphocytes (ALI), that have been collected in the early phase of therapy, and that are functionally activated. AIMS OF THE STUDY: Primary endpoint of this prospective trial was the evaluation of the efficacy of ALI in combination with pre-emptive CI administration early post ASCT in patients affected by R/R HL. Secondary pre-clinical endpoint was the study of the peripheral blood lymphocyte subpopulation, pre and post adoptive immune cell therapy and CI administration. METHODS: HL patients under the age of 60 with active R/R disease who have already failed at least two chemotherapy lines and Brentuximab (BV) were eligible for the trial. All enrolled patient underwent early lymphocyte apheresis, with a target cell dose of 5x107 CD3+/kg. All patients then received ASCT with FEAM conditioning. After ASCT, the first ALI was delivered 7 days after engraftment. ALI dosing was incremental, one logarithm at each step, starting from 1x104/kg in the first infusion to a maximum of 1x107/kg in the fourth and last infusion. Each ALI was followed after 48 hours by the administration of Nivolumab 240 mg flat dose. The second ALI dose was administered at 14 days after the first one. The third and the fourth were given every 21 days. Lymphocyte subpopulations were extensively studied on peripheral blood samples before and after each ALI and each Nivolumab administration, by 8-colours flow cytometry. Clinical response was evaluated 21 days after completion of the fourth ALI + Nivolumab. RESULTS: Six R/R HD patient have completed treatment so far and one is currently being treated. All patients failed to achieve CR with chemotherapy and then progressed during BV therapy. PET scan before ASCT showed progressing disease in all patients, with multiple-extra nodal involvement in 5 of them. All patients achieved complete hematological engraftment after a median of 10 days (8-12) from ASCT. Overall, infusion of ALI resulted in significantly higher lymphocyte counts at day 90, as compared to HL patients receiving the same conditioning without ALI (p

Description: Background Natural Killer (NK) cells have been widely studied due to their non-major histocompatibility complex (MHC)-restricted cytotoxicity towards transformed or virally infected target cells. In the setting of hematopoietic stem cell transplantation (HSCT), donor NK cells may be "alloreactive" as their killer immunoglobuline-like receptors (KIRs) do not recognize their ligands on recipient human leukocyte antigen (HLA) class I molecules (i.e. KIR-ligands), leading to NK activation. NK alloreactivity can often occur in haploidentical HSCT (Haplo-HSCT), by means of KIR/KIR-L mismatch in graft versus host (GvH) direction, contributing to graft-versus leukemia (GvL) effect, clearing residual leukemic blasts. In the last decade, several studies have shown that NK cells alloreactivity plays a role in T-depleted Haplo-HSCT leading to higher disease free survival rates for patients transplanted from NK-alloreactive donors; recent studies have also shown that donors having KIR B haplotypes (characterized by the presence of more activating KIR) or expressing KIR2DS1 correlated with a better clinical outcome of transplantation. Thus, these NK cell features might be positively considered in the donor selection strategy. Materials and Methods: We analyzed NK-alloreactivity in the setting of unmanipulated Haplo-HSCT with post-transplant cyclophosphamide for patients affected by acute myeloid leukemia or myelodisplastic syndromes. 101 consecutive patients transplanted from September, 2010 to October, 2014 were enrolled, with the big majority of donors and patients studied for HLA-genotype and KIR. Results: Disease status at HSCT was the most relevant factor affecting outcome (p =2) or who had KIR2DS1 was not associated with better outcome (p 0.67 and p 0.89, respectively). We observed an high expression of CD56 and inhibitory receptors such as NKG2A on surface of NK cells in post-HSCT samples, suggesting that NK-cell function could be inhibited in unmanipulated haploidentical setting. Conclusions NK alloreactivity seems not to play a role in preventing leukemia relapse in unmanipulated haploidentical transplantation with post-transplantation. The different immunosuppressive approach of this Haplo-HSCT setting compared to T-depleted Haplo-HSCT, with concomitant use of cyclosporine from early transplant days, which has been shown to interact and possibly inhibit NK cells in vivo, and post transplant cyclophosphamide effects, selectively killing activated T-cell and inducing long-term tolerance, could affect NK efficacy. Further studies are needed to better understand the complexity of this intriguing issue, leading to a more complete definition of NK cell functions in this Haplo-HSCT setting. Disclosures No relevant conflicts of interest to declare.

Description: BACKROUND Hodgkin lymphoma (HL) is a lymphoid malignancy of B-cell origin with a high long-term survival. Despite the efficacy of frontline therapy, about 30% of patient will show relapse or refractory disease (R/R). In this patient population, the treatment of choice consists of salvage chemotherapy followed by intensive conditioning regimen and autologous stem cell transplantation (ASCT). However 30-50% of patients receiving salvage chemotherapy fail to achieve at least PR and further therapy with Brentuximab-Vedotin (BV) may be administered to induce a clinical response. Nonetheless, therapeutic options for truly refractory patients are still limited. Recently, immune-check point inhibitors have shown promising results in HL patients relapsed after ASCT. Anti-PD1 Nivolumab is currently approved with this indication. Unfortunately,expected CR rate is only about 20%.Thus, we reasoned that earlier administration of Nivolumab, as post-ASCT consolidation, might improve its efficacy. However, several reports have highlighted the importance of patient immune-competence, which is severely impaired in heavily pre-treated lymphoma patients undergoing ASCT, to achieve durable response with anti-PD1 immunotherapy. AIMS OF THE STUDY Here we report the preliminary results of a prospective trial investigating the feasibility, and the efficacy, in terms of both immunological recovery andclinical response,ofthe reinfusion of autologous lymphocytes (ALI), early after ASCT, concomitant with anti-PD1 consolidation immunotherapy in very high-risk HD patients. METHODS Patients under the age of 60 with high risk HD identified by PET2 or PET6 positivity following ABVD were scheduled for a pre-emptive lymphocyte apheresis with a target of 5x107 CD3+/kg. Patients who failed to achieve at least PR with salvage chemotherapy proceeded to ASCT with FEAM conditioning followed by early Nivolumab and ALI.The first ALI was performed 7 days after engraftment; the second ALI was administered at day +14 after the first dose whereas the third and the fourth doses were given every 21 days. ALI dosing was incremental, one logarithm at each infusion, starting from 1x104CD3+ cells/kg in the first infusion to a maximum of 1x107/kg in the fourth and last infusion. Each ALI was followed within 48 hours by the administration of Nivolumab 240 mg flat dose. Toxicity was evaluated and graduated according to CTCAE-EORTC standards. Circulating lymphocyte subpopulationswere extensively studied before and after each ALI and each Nivolumab administration by 12-colours flow cytometry. Clinical response was evaluated 21 days after completion of the fourth ALI + Nivolumab. PRELIMINARY RESULTS Four R/R HD patients have completed the treatment and3are currently under treatment. All patientshad failed to achieve CR with first and second line chemotherapy. PET scan before ASCT showed progressing disease in all patients despite BV therapy, with multiple-extra nodal involvement in 3 of them. Study patients underwent ASCT with FEAM conditioning and achieved complete engraftment after a median of 10 days (8-12). ALI induced faster T-cell recovery (p

Description: Background: Therapy-related acute myeloid leukemia (t-AML) or AML evolving from a myelodisplastic syndrome are characterized by a low response rate to conventional chemotherapy and high relapse rate with poor overall survival (OS) despite intensive treatment and allogeneic stem cell transplantation consolidation (HSCT). CPX-351 is a dual-drug liposomal encapsulation of cytarabine and daunorubicin, in a fixed synergistic 1:5 molar ratio. CPX-351 has been approved by FDA for the treatment of patients affected by t-AML or AML with myelodisplasia-related changes (MRC-AML) based on the results of a randomized phase III trial where the drug was compared with conventional 3+7 induction (Lancet et al, JCO 2018). Notably, CPX-351 proved to increase survival probabilities in comparison with standard chemotherapy even among patient achieving complete remission (CR) and proceeding to HSCT, suggesting that CPX-351 may allow deeper responses. However, few information is available on minimal residual disease (MRD) assessment after CPX-351 treatment, or on the impact of molecular alterations on response probability. Aims: The aim of this study was to evaluate the clinical activity of CPX-351 in a real life setting, with particular focus on molecular characterization at diagnosis and MRD evaluation in responding patients. Methods: Seventy five patients were enrolled in a compassionate use program (CUP) in 37 Italian Hematology Centers. CUP started on December 2018 and closed on June 2019. Data collection began on July 2019 and was completed, at the time of writing, for 25/75 patients, enrolled in 9 Centers. Median age was 69 years (56-73), 10 patients were female. Molecular and MRD analysis were performed in each Center as per internal standard. MRD was assessed in most Centers with multicolor flow cytometry. NPM1 mutation was found in 2/22 assessed patients, FLT3-ITD in 3/22, with low allelic burden in 2/3 patients. TP53 mutations have been found in 4/12 patients.Four patients had complex Karyotype, one had isolated del(7q) whereas the remaining 19 had normal karyotype. Six patients had t-AML; 15 patients were previously diagnosed with MDS and 5 of them had already received hypomethilating agents for a median of 5 cycles (2-49). European Leukemia net risk score was low in 2 (8%), intermediate in 12 (48%) and high in 11 (44%) patients. Most patients (20/25) had relevant comorbidities upon enrollment, mostly COPD, diabetes and/or hypertension. As per CUP inclusion criteria, all patients had normal left ventricular function at the time of enrollment (defined by a normal ejection fraction). Results: Induction-related mortality was 2/25 (8%). Fourteen patients experienced grade 〉1 extra hematological adverse event during induction (mainly infections). Alopecia was observed in 4/25 patients (16%).Response was assessed in 20 patients:2 patients died during induction and 3 patients were not yet evaluated for response at the time of analysis. CR or CRi was observed in 19/22 (86.3%). MRD was performed in 11 patients, with 4 of them achieving flow MRD negativity after first cycle (defined as

Description: BACKGROUND AND AIMS Allogeneic bone marrow transplantation (BMT) offers the greatest chance of cure for high-risk acute myeloid leukemia (AML) patients. Persistence of disease or high levels of pre BMT minimal residual disease (MRD) have been reported to predict relapse risk after BMT. Multicolor flow cytometry (MFC) is the most common tool to evaluate MRD, whereas WT1 gene expression is the most widely applicable and standardized molecular MRD marker in AML. The aim of this study was to analyze the role of pre-BMT combined MFC-molecular MRD assessment as predictor for the post-transplant relapse risk. MATERIALS AND METHODS We retrospectively analyzed the outcome of 224 consecutive AML patients receiving allo-BMT in 1st or 2nd CR. Pre-BMT marrow samples were analysed for WT1 expression and MFC as MRD evaluation. Median age at transplant was 44 years. Disease phase was CR1 in 161 (72%) and CR2 in 63 patients (28%). BMT conditioning wasmyeloablative in 163 (73%), whereas 61 patients (27%) received reduced intensity conditioning. Stem cell source was HLA-identical sibling in 79 (35%),haploidentical in 59 (27%) and alternative donor in 86 (38%).Median follow-up was 64 months (95% CI 50.3 - 77.3 months). Cumulative Incidence of Relapse (CI of relapse) at various time-points was calculated in competing risk analysis by takingin account non relapse mortality as competing event. Overall Survival (OS) was calculated from the time of BMT until death by any cause or last follow-up. A positive MFC MRD was defined by the presence of no less than 25 clustered leukemic cells/105 total events (threshold of 2.5x10-4 residual leukemic cells) at four-color flow-cytometry. WT1 copy number/Abl copy number 500x104 was used as cut-off value for abnormal WT1 expression. RESULTS Relapse occurred in 62 patients (27.7%). Three-year estimate of CI of relapse was 25.9% (median not reached). The CI of relapse was significantly affected by occurrence of acute GVHD (lower for grade ≥2, p