Search

Introduction: Renal allograft biopsy is the gold standard for the detection of histological lesions of chronic allograft dysfunction. The identification of a noninvasive routine test would be desirable. Elastosonography is used to assess tissue stiffness according to viscosity, and no data are available on the use of point quantification shear-wave elastography (ElastPQ) for the evaluation of renal chronic lesions.Research Question: To evaluate the feasibility of ElastPQ to assess cortical allograft stiffness and to determine the correlation of clinical, biological, and pathological factors with the diagnostic accuracy of kidney stiffness values in patients with histological lesions.Design: Forty-two patients underwent kidney transplant biopsy and 10 valid measurements of ElastPQ, blindly performed by 2 operators. The interobserver reproducibility was assessed according to intraclass correlation coefficient. The ElastPQ measurements and the clinical data were compared using the Spearman correlation analysis.Results: 97.6% reliable measurements were obtained using ElastPQ, with an excellent interobserver agreement. The kidney stiffness was significantly higher in the patients with a time since transplantation >12 months and was correlated with chronic lesions (interstitial fibrosis, tubular atrophy transplant glomerulopathy, and mesangial matrix), with the interstitial fibrosis/tubular atrophy, score and with the sum of the scores of the chronic lesions. Mesangial matrix increase is the only independent determinant of kidney stiffness.Discussion: ElastPQ is a noninvasive, reproducible, and sensitive diagnostic tool able to detect moderate/severe chronic lesions. Its routine use during follow-up can identify patients eligible for biopsy, which remains the gold standard exam for detecting chronic allograft dysfunction.

Purpose Richter syndrome (RS) is a rare event in chronic lymphocytic leukemia (CLL) that is influenced by biological factors and prior CLL treatments. Ibrutinib is a Bruton tyrosine kinase inhibitor that has shown remarkable efficacy in CLL; however, little is known about its relationship to RS. We report a case of ibrutinib efficacy against CLL in a patient with prolonged remission of RS.Methods The patient was diagnosed with CLL in 2003. Biological findings at onset included absent ZAP70 expression, mutated IGVH, and NOTCH1 mutation. He was treated with FCR with partial response. In 2013, he progressed to RS, not clonally related to the underlying CLL. The patient was treated with anthracycline- and platinum-based regimens, obtaining a complete remission. After 3 years, he presented a CLL progression with worsening lymphocytosis, anemia, thrombocytopenia, increased splenomegaly, and lymphadenopathies. Positron emission tomography-computed tomography scan excluded pathologic uptake. Thus, he was started on ibrutinib.Results At 12 months’ follow-up, we observed white blood cell normalization, increased hemoglobin and platelet levels, disappearance of lymphadenopathy, and spleen size reduction. Therapy was well-tolerated with no evidence of RS.Conclusion This case demonstrates sustained RS remission in a patient with CLL under ibrutinib therapy, thus improving our knowledge on the use of this new drug in CLL and beyond.

Some “worrisome” imaging features, such as nonsmooth tumor margins, peritumoral enhancement, two-trait predictor of venous invasion (“internal arteries” and “hypoattenuating halos”), and large tumor size were used to significantly predict the presence of microvascular invasion in hepatocellular carcinoma.

Glucocorticoids (GC) are widely used as antiinflammatory/immunosuppressive drugs and antitumor agents in several types of lymphoma and leukemia. Therapeutic doses of GC induce growth-suppressive and cytotoxic effects on various leukocytes including B cells. Molecular mechanisms of GC action include induction of GC target genes. Glucocorticoid-induced leucine zipper (GILZ) is a rapidly, potently, and invariably GC-induced gene. It mediates a number of GC effects, such as control of cell proliferation, differentiation, and apoptosis. Here we show that deletion of GILZ in mice leads to an accumulation of B lymphocytes in the bone marrow, blood, and lymphoid tissues. Gilz knockout (KO) mice develop a progressive nonlethal B lymphocytosis, with expansion of B220+cells in the bone marrow and in the periphery, dependent on increased B-cell survival. Decreased B-cell apoptosis in mice lacking GILZ correlates with increased NF-κB transcriptional activity and Bcl-2 expression. B cell–specific gilzKO mice confirmed that the effect of GILZ deletion is B-cell self-intrinsic. These results establish GILZ as an important regulator of B-cell survival and suggest that the deregulation of GILZ expression could be implicated in the pathogenesis of B-cell disorders.

Nucleophosmin (NPM1) mutations represent an attractive therapeutic target in acute myeloid leukemia (AML) because they are common (∼30% AML), stable, and behave as a founder genetic lesion. Oncoprotein targeting can be a successful strategy to treat AML, as proved in acute promyelocytic leukemia by treatment with all-trans retinoic acid (ATRA) plus arsenic trioxide (ATO), which degrade the promyelocytic leukemia (PML)–retinoic acid receptor fusion protein. Adjunct of ATRA to chemotherapy was reported to be beneficial for NPM1-mutated AML patients. Leukemic cells with NPM1 mutation also showed sensibility to ATO in vitro. Here, we explore the mechanisms underlying these observations and show that ATO/ATRA induce proteasome-dependent degradation of NPM1 leukemic protein and apoptosis in NPM1-mutated AML cell lines and primary patients’ cells. We also show that PML intracellular distribution is altered in NPM1-mutated AML cells and reverted by arsenic through oxidative stress induction. Interestingly, similarly to what was described for PML, oxidative stress also mediates ATO-induced degradation of the NPM1 mutant oncoprotein. Strikingly, NPM1 mutant downregulation by ATO/ATRA was shown to potentiate response to the anthracyclin daunorubicin. These findings provide experimental evidence for further exploring ATO/ATRA in preclinical NPM1-mutated AML in vivo models and a rationale for exploiting these compounds in chemotherapeutic regimens in clinics.

Nucleophosmin (NPM1) mutations represent an attractive therapeutic target in acute myeloid leukemia (AML) because they are common (∼30% AML), stable, and behave as a founder genetic lesion. Oncoprotein targeting can be a successful strategy to treat AML, as proved in acute promyelocytic leukemia by treatment with all-transretinoic acid (ATRA) plus arsenic trioxide (ATO), which degrade the promyelocytic leukemia (PML)–retinoic acid receptor fusion protein. Adjunct of ATRA to chemotherapy was reported to be beneficial for NPM1-mutated AML patients. Leukemic cells with NPM1mutation also showed sensibility to ATO in vitro. Here, we explore the mechanisms underlying these observations and show that ATO/ATRA induce proteasome-dependent degradation of NPM1 leukemic protein and apoptosis in NPM1-mutated AML cell lines and primary patients' cells. We also show that PML intracellular distribution is altered in NPM1-mutated AML cells and reverted by arsenic through oxidative stress induction. Interestingly, similarly to what was described for PML, oxidative stress also mediates ATO-induced degradation of the NPM1 mutant oncoprotein. Strikingly, NPM1 mutant downregulation by ATO/ATRA was shown to potentiate response to the anthracyclin daunorubicin. These findings provide experimental evidence for further exploring ATO/ATRA in preclinical NPM1-mutated AML in vivo models and a rationale for exploiting these compounds in chemotherapeutic regimens in clinics.

Hairy cell leukemia (HCL) shows unique clinicopathological and biological features. HCL responds well to purine analogs but relapses are frequent and novel therapies are required. BRAF-V600E is the key driver mutation in HCL and distinguishes it from other B-cell lymphomas, including HCL-like leukemias/lymphomas (HCL-variant and splenic marginal zone lymphoma). The kinase-activating BRAF-V600E mutation also represents an ideal therapeutic target in HCL. Here, we investigated the biological and therapeutic importance of the activated BRAF–mitogen-activated protein kinase kinase (MEK)–extracellular signal-regulated kinase (ERK) pathway in HCL by exposing in vitro primary leukemic cells purified from 26 patients to clinically available BRAF (vemurafenib; dabrafenib) or MEK (trametinib) inhibitors. Results were validated in vivo in samples from vemurafenib-treated HCL patients within a phase 2 clinical trial. BRAF and MEK inhibitors caused, specifically in HCL (but not HCL-like) cells, marked MEK/ERK dephosphorylation, silencing of the BRAF-MEK-ERK pathway transcriptional output, loss of the HCL-specific gene expression signature, downregulation of the HCL markers CD25, tartrate-resistant acid phosphatase, and cyclin D1, smoothening of leukemic cells’ hairy surface, and, eventually, apoptosis. Apoptosis was partially blunted by coculture with bone marrow stromal cells antagonizing MEK-ERK dephosphorylation. This protective effect could be counteracted by combined BRAF and MEK inhibition. Our results strongly support and inform the clinical use of BRAF and MEK inhibitors in HCL.

Background: The question of which parameters may be informative on venetoclax outcome in chronic lymphocytic leukemia (CLL) is still unclear. Furthermore, the choice to treat with venetoclax can be challenging in patients with baseline characteristics or comorbidities that may potentially favor some specific adverse events.Objectives: This study was aimed to evaluate whether age, fitness status, patients’/disease characteristics, or concomitant medications may predict outcomes in CLL patients receiving venetoclax.Design: Retrospective observational study.Methods: Impact of age, presence of Cumulative Illness Rating Scale (CIRS) >6 or severe organ impairment (CIRS3+), Eastern Cooperative Oncology Group–Performance Status (ECOG-PS), renal function, and concomitant medications were retrospectively analyzed on treatment management (definitive discontinuation due to toxicity, discontinuation due to toxicity, Tox-DTD; permanent dose reduction, PDR) and survival [progression free survival (PFS), event free survival (EFS), overall survival (OS)] in unselected patients receiving venetoclax monotherapy in common practice.Results: A total of 221 relapsed/refractory patients were included. Tox-DTD and PDR were reported in 5.9% and 21.7%, respectively, and were not influenced by any fitness parameter, age, number or type of concomitant medication, baseline neutropenia, or impaired renal function. None of these factors were associated with tumor lysis syndrome (TLS) development. Age and coexisting conditions had no influence on PFS and EFS. At univariate analysis, OS was significantly shorter only in patients with ECOG-PS >1 (p< 0.0001) and elderly (⩾65 years) with CIRS >6 (p= 0.014) or CIRS3+ (p= 0.031). ECOG-PS >1 retained an independent role only for EFS and OS. While Tox-DTD affected all survival outcomes, no differences in PFS were reported among patients permanently reducing dose or interrupting venetoclax for > 7 days.Conclusion: Clinical outcome with venetoclax is not influenced by comorbidities, patients’ clinical characteristics, or concomitant medications. Differently from other targeted therapies, this demonstrates that, except ECOG-PS, none of the parameters generally considered for treatment choice, including baseline neutropenia or impaired renal function, should rule the decision process with this agent. Anyway, if clinically needed, a correct drug management does not compromise treatment efficacy and may avoid toxicity-driven discontinuations.Plain Language Summary Chapter 1: Why was this study done? Chapter 2: Which are the main findings of the study? Chapter 3: How these findings may impact on clinical practice? Coexisting conditions and concomitant medications do not affect venetoclax management and survival in chronic lymphocytic leukemia • The question of which parameters may be informative on venetoclax outcome in chronic lymphocytic leukemia is still unclear. Furthermore, the choice to treat with venetoclax can be challenging in patients with baseline characteristics or comorbidities that may potentially favor some specific adverse events (e.g. compromised renal function or baseline neutropenia). • In our large series of patients treated outside of clinical trials, we demonstrated that neither age, fitness, comorbidities nor concomitant medications impact on venetoclax management and survival. Importantly, patients presenting with baseline neutropenia or impaired renal function did not have a higher rate of dose reductions or toxicity-driven discontinuations, thus further underlining that venetoclax may be safely administered even in those categories with no preclusions. • Differently from other targeted agents, our data demonstrate that none of the baseline factors commonly considered in treatment decision process retains a role with venetoclax. Finally, permanent dose reductions and temporary interruptions did not adversely impact PFS suggesting that, if clinically needed, a correct drug management should be adopted with no risk of compromising venetoclax efficacy.

Coscia: Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Shire: Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees; Karyopharm Therapeutics: Research Funding. Ciolli:Abbvie: Research Funding; Janssen: Honoraria. Laurenti:Janssen: Honoraria; Gilead: Honoraria; AbbVie: Honoraria; Roche: Honoraria. Sportoletti:AbbVie: Honoraria; Janssen: Honoraria. Reda:Janssen: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees. Varettoni:Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Travel/accommodations/expenses; Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees; AbbVie: Other: Travel/accommodations/expenses. Mauro:Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Astrazeneca: Membership on an entity's Board of Directors or advisory committees; Jannsen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Octopharma: Consultancy; Shire-Takeda: Membership on an entity's Board of Directors or advisory committees. Murru:Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Vitale:Janssen: Honoraria. Montillo:Gilead: Honoraria, Speakers Bureau; Verastem: Honoraria; Astra Zeneca: Honoraria; Janssen: Honoraria, Speakers Bureau; AbbVie: Honoraria, Speakers Bureau; F. Hoffmann-La Roche: Honoraria, Research Funding. Tedeschi:Janssen: Honoraria, Speakers Bureau; Acerta: Honoraria, Speakers Bureau; Sunesis: Honoraria, Speakers Bureau; Beigene: Honoraria, Speakers Bureau; Abbvie: Honoraria, Speakers Bureau.

Visentin: Janssen: Honoraria; Gilead: Honoraria; Abbvie: Honoraria. Mauro:Takeda: Membership on an entity's Board of Directors or advisory committees; Octopharma: Consultancy; Astrazeneca: Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Jannsen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Vitale:Janssen: Honoraria. Ciolli:Janssen: Honoraria; Abbvie: Research Funding. Sportoletti:Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Rigolin:Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Murru:Gilead: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Gozzetti:Janssen: Honoraria, Research Funding; Takeda: Honoraria; Amgen: Honoraria. Molica:Roche: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Membership on an entity's Board of Directors or advisory committees. Marchetti:Pfizer: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees. Scarfo:Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Honoraria. Reda:Gilead: Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees. Coscia:Karyopharm Therapeutics: Research Funding; Shire: Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Laurenti:Gilead: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AbbVie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Roche: Membership on an entity's Board of Directors or advisory committees. Pizzolo:Abbvie: Speakers Bureau; janssen: Speakers Bureau. Semenzato:Takeda: Honoraria; Roche: Honoraria; Abbvie: Honoraria. Foà:Novartis: Speakers Bureau; Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Roche: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte: Speakers Bureau; Roche: Membership on an entity's Board of Directors or advisory committees. Cuneo:Gilead: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Trentin:Shire: Honoraria; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Octapharma: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees.

Tedeschi: Abbvie: Honoraria, Speakers Bureau; Acerta: Honoraria, Speakers Bureau; Janssen: Honoraria, Speakers Bureau; Beigene: Honoraria, Speakers Bureau; Sunesis: Honoraria, Speakers Bureau. Coscia:Karyopharm Therapeutics: Research Funding; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees; Shire: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Ciolli:Abbvie: Research Funding; Janssen: Honoraria. Reda:Abbvie: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees. Laurenti:Janssen: Honoraria; Gilead: Honoraria; AbbVie: Honoraria; Roche: Honoraria. Varettoni:Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Travel/accommodations/expenses; Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees; AbbVie: Other: Travel/accommodations/expenses. Murru:Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Sportoletti:AbbVie: Honoraria; Janssen: Honoraria. Vitale:Janssen: Honoraria. Di Raimondo:Takeda: Consultancy, Honoraria; GSK: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Amgen, Takeda, Novartis: Honoraria; GILEAD, Incyte: Research Funding. Montillo:F. Hoffmann-La Roche: Honoraria, Research Funding; AbbVie: Honoraria, Speakers Bureau; Janssen: Honoraria, Speakers Bureau; Astra Zeneca: Honoraria; Gilead: Honoraria, Speakers Bureau; Verastem: Honoraria.

Background. Approximately 70% of newly diagnosed chronic lymphocytic leukemia (CLL) patients present in early Binet or Rai stage, may never require treatment, and may have a life expectancy similar to that of the general population. Two independent and recent studies have identified the clinical and immunogenetic variables associated with shorter time to first treatment (TTFT) in Binet A and Rai 0 CLL (Condoluci et al., Blood2020; Cohen et al., Haematologica2020). However, the clinical impact of gene mutations in predicting TTFT is not completely understood.

The NPM1mutation is the most frequent genetic alteration thus far identified in acute myeloid leukemia (AML). Despite progress in the clinical and biological characterization of NPM1-mutated AML, the role of NPM1mutation in leukemogenesis in vivo has not been fully elucidated. We report a novel mouse model that conditionally expresses the most common human NPM1mutation (type A) in the hematopoietic compartment. In Npm1-TCTG/WT;Cre+mice, the NPM1 mutant localized in the cytoplasm (NPMc+) of bone marrow (BM) cells. The mutant mice developed no AML after 1.5-year follow-up. However, NPMc+expression determined a significant platelet count reduction and an expansion of the megakaryocytic compartment in the BM and spleen. Serum thrombopoietin levels overlapped in mutant vs control mice, and BM cells from Npm1-TCTG/WT;Cre+mice formed more megakaryocytic colonies in vitro. Moreover, we demonstrated the up-regulation of microRNAs (miRNAs; miR-10a, miR-10b,and miR-20a) inhibiting megakaryocytic differentiation along with increased expression of HOXBgenes. Notably, these findings mimic those of human NPM1-mutated AML, which also exhibits a similar miRNA profile and expansion of the megakaryocytic compartment. Our mouse model provides evidence that the NPM1 mutant affects megakaryocytic development, further expanding our knowledge of the role of NPM1 mutant in leukemogenesis.

The NPM1 mutation is the most frequent genetic alteration thus far identified in acute myeloid leukemia (AML). Despite progress in the clinical and biological characterization of NPM1-mutated AML, the role of NPM1 mutation in leukemogenesis in vivo has not been fully elucidated. We report a novel mouse model that conditionally expresses the most common human NPM1 mutation (type A) in the hematopoietic compartment. In Npm1-TCTG/WT;Cre+ mice, the NPM1 mutant localized in the cytoplasm (NPMc+) of bone marrow (BM) cells. The mutant mice developed no AML after 1.5-year follow-up. However, NPMc+ expression determined a significant platelet count reduction and an expansion of the megakaryocytic compartment in the BM and spleen. Serum thrombopoietin levels overlapped in mutant vs control mice, and BM cells from Npm1-TCTG/WT;Cre+ mice formed more megakaryocytic colonies in vitro. Moreover, we demonstrated the up-regulation of microRNAs (miRNAs; miR-10a, miR-10b, and miR-20a) inhibiting megakaryocytic differentiation along with increased expression of HOXB genes. Notably, these findings mimic those of human NPM1-mutated AML, which also exhibits a similar miRNA profile and expansion of the megakaryocytic compartment. Our mouse model provides evidence that the NPM1 mutant affects megakaryocytic development, further expanding our knowledge of the role of NPM1 mutant in leukemogenesis.

Hastening posttransplantation immune reconstitution is a key challenge in human leukocyte antigen (HLA)–haploidentical hematopoietic stem-cell transplantation (HSCT). In experimental models of mismatched HSCT, T-regulatory cells (Tregs) when coinfused with conventional T cells (Tcons) favored posttransplantation immune reconstitution and prevented lethal graft-versus-host disease (GVHD). In the present study, we evaluated the impact of early infusion of Tregs, followed by Tcons, on GVHD prevention and immunologic reconstitution in 28 patients with high-risk hematologic malignancies who underwent HLA-haploidentical HSCT. We show for the first time in humans that adoptive transfer of Tregs prevented GVHD in the absence of any posttransplantation immunosuppression, promoted lymphoid reconstitution, improved immunity to opportunistic pathogens, and did not weaken the graft-versus-leukemia effect. This study provides evidence that Tregs are a conserved mechanism in humans.

After the discovery of NPM1-mutated acute myeloid leukemia (AML) in 2005 and its subsequent inclusion as a provisional entity in the 2008 World Health Organization classification of myeloid neoplasms, several controversial issues remained to be clarified. It was unclear whether the NPM1 mutation was a primary genetic lesion and whether additional chromosomal aberrations and multilineage dysplasia had any impact on the biologic and prognostic features of NPM1-mutated AML. Moreover, it was uncertain how to classify AML patients who were double-mutated for NPM1 and CEBPA. Recent studies have shown that: (1) the NPM1 mutant perturbs hemopoiesis in experimental models; (2) leukemic stem cells from NPM1-mutated AML patients carry the mutation; and (3) the NPM1 mutation is usually mutually exclusive of biallelic CEPBA mutations. Moreover, the biologic and clinical features of NPM1-mutated AML do not seem to be significantly influenced by concomitant chromosomal aberrations or multilineage dysplasia. Altogether, these pieces of evidence point to NPM1-mutated AML as a founder genetic event that defines a distinct leukemia entity accounting for approximately one-third of all AML.

Although NPM1 gene mutations leading to aberrant cytoplasmic expression of nucleophosmin (NPMc+) are the most frequent genetic lesions in acute myeloid leukemia, there is yet no experimental model demonstrating their oncogenicity in vivo. We report the generation and characterization of a transgenic mouse model expressing the most frequent human NPMc+ mutation driven by the myeloid-specific human MRP8 promoter (hMRP8-NPMc+). In parallel, we generated a similar wild-type NPM trans-genic model (hMRP8-NPM). Interestingly, hMRP8-NPMc+ transgenic mice developed myeloproliferation in bone marrow and spleen, whereas nontransgenic littermates and hMRP8-NPM transgenic mice remained disease free. These findings provide the first in vivo evidence indicating that NPMc+ confers a proliferative advantage in the myeloid lineage. No spontaneous acute myeloid leukemia was found in hMPR8-NPMc+ or hMRP8-NPM mice. This model will also aid in the development of therapeutic regimens that specifically target NPMc+.

Nucleophosmin (NPM1) gene mutations, which cause aberrant cytoplasmic expression of nucleophosmin (NPMc), are the most frequent genetic alteration in acute myeloid leukemia (AML), being found in about 30% cases. The present review summarizes recent advances in the biology, diagnosis, prognosis and therapy of NPM1-mutated AML.

Introduction:Treatment-free remission (TFR) in chronic myeloid leukemia (CML) is demonstrated to be achievable and recommended for patients (pts) in sustained deep molecular response (sDMR) who can discontinue tyrosine kinase inhibitor (TKI) treatment and maintain responses in ~50% of cases. While the feasibility and safety of TKI cessation have been largely demonstrated, the strategies of TFR optimization are yet to be clarified. Studies (eg. DESTINY) investigating de-escalation, mainly after imatinib, suggested that a stepwise approach may favor TFR outcome. We present the interim results of the phase 2, prospective, multicenter DANTE study (NCT03874858) evaluating de-escalation and TFR in Italian pts with CML in chronic phase (CML-CP) treated with nilotinib (NIL).

BackgroundTyrosine kinase inhibitors (TKIs) revolutionized treatment of chronic myeloid leukemia (CML). However, the first months of therapy are crucial, as optimal response is defined as the achievement of molecular milestones at 3, 6 and 12 months (mo.) and as many toxicities, also causing a TKI switch, are more frequent in the 1st year.

Introduction:All the available CLL therapies differ for relevant aspects as duration of response, mode of administration, treatment duration and adverse events: the CHOICE study was designed to investigate CLL patients' Quality of Life (QoL) and preferences towards different treatment attributes through a Discrete Choice Experiment (DCE) in Italy. Due to the timeline of the study, started in Feb2020, the collected data offer an insight of patients' perception and attitude during the 1 stwave of the COVID-19 pandemic, as opposed to other DCE results available in CLL (1-2).

Introduction

Introduction:In previously untreated patients with chronic lymphocytic leukemia (CLL), treatment with ibrutinib plus rituximab improved progression-free survival (PFS) and overall survival (OS) compared to the standard fludarabine, cyclophosphamide and rituximab (FCR) chemoimmunotherapeutic regimen, based on the results of the phase III ECOG-E1912 trial. The improvement in PFS with ibrutinib plus rituximab was observed in patients with unmutated immunoglobulin heavy chain variable region gene (IGHV) but not in those with an IGHV mutated profile. However, the efficacy of ibrutinib compared to FCR has not yet been investigated in the real-world setting.

The use of novel small molecule inhibitors alone or in combination with anti-CD20 monoclonal antibodies for chronic lymphocytic leukemia (CLL) has raised a number of questions on efficacy, tolerability, long-term treatment adherence in patients with heterogeneous clinical features. To fill this gap, we designed a study focusing on treatment sequencing in patients with CLL in order to (i) compare the outcome of patients treated with chemoimmunotherapy (CIT) combinations in first-line versus those receiving Bruton's tyrosine kinase inhibitors (BTKi); (ii) characterize the efficacy and tolerability of venetoclax-based regimens; (ii) understand the impact of treatment sequencing when it comes to chemo-free options including venetoclax after BTKi and vice versa. Data from consecutive sets of patients diagnosed with CLL between 2000-2020 attended at 77 institutions affiliated with ERIC were collected and analyzed. Collected variables included: demographics, clinical stage at diagnosis, IGHV gene somatic hypermutation status; cytogenetic status for chromosomes 11q, 13q 17p and 12 determined by fluorescence in situhybridization; TP53gene mutation status; treatment; treatment response; discontinuation; reason for discontinuation; death. We included 9173 patients with a diagnosis of CLL who received at least one line of treatment. The median age at diagnosis was 67 years with a male:female ratio of 1.9. The median follow-up was 78 months (IQR, 48-120 months). Regarding novel targeted agents, 1860/9173 (20.2%) patients had received at least one line of treatment with BTKi (ibrutinib, n=1788; acalabrutinib, n=72) over the disease course; 631/9173 (6.9%) with venetoclax; and, 447/9173 (4.9%) with the PI3K inhibitor idelalisib. Seventy-nine patients were treated with both BTKi and venetoclax (59 BTKi followed by BCL2i, 20 vice versa). At last follow-up, 5870/9173 patients (64.0%) were alive, 3229/9173 (35.2%) died and 74/9173 (0.8%) were lost to follow-up. Patients treated with BTKi in first-line were enriched for TP53aberrations [del(17p) 27.6%, TP53mutation 26.3%] and unmutated IGHV genes (69%) and obtained an ORR of 87.7%. Of these, 136 (26.3%) discontinued treatment after a median of 1.2 years (0.07-5.98); main reasons of discontinuation were toxicity (40.5%) and failure (26.2%). Among 631 patients treated with venetoclax at any line, 100 (15.8%) received BCL2 +/- anti-CD20 as first-line; 170 (26.9%) as second line (125 previously treated with CIT, 27 with BTKi); and, 361 as third or subsequent line. ORR ranged between 71.5% (≥3 lines) with 30.5% CR/CRi to 90.3% (first-line) with 68.1% CR/CRi. Treatment discontinuation was due to toxicity in 28.6% of patients treated in the first-line, and 17.6% and 21.8% of patients treated in second and third-or-higher-line, respectively. Disease progression led to treatment discontinuation in 14.3%, 20.6% and 33.6% in first, second and third-or-higher line, respectively. CIT was used as front-line treatment in 5465 patients (59.6%). Of these, 2070 (37.9%) and 1018 (18.6%) patients received a second and third line of treatment, respectively. The great majority (865/1086 cases, 79.7%) of patients who received a second line before 2014 were retreated with CIT, most commonly Bendamustine-Rituximab (284/1086, 26.1%) and Fludarabine-Cyclophosphamide-Rituximab (252/1086, 23.2%); alemtuzumab monotherapy was used in 55/1086 (5%) of patients. After 2014, 415/984 patients (42.1%) were retreated with BTKi; 93 (9.5%) with venetoclax; 70 (7.2%) with idelalisib; 50 (5%) with Alemtuzumab monotherapy, and 315 (32%) with CIT. Similarly, in the third-or-higher line of treatment, most patients (86.3%) were retreated with CIT before 2014, while BTKi, BCL2i, and PI3Ki were mainly used after 2014 (in 43.1%, 15.7% and 14.7% of cases, respectively). Finally, our cohort included 1075 patients with TP53aberrations. The ORR of patients receiving BTKis (n=171) as first-line of treatment was 86.5% (22.2 CR+64.3 PR), while the ORR with venetoclax +/- anti-CD20 (n=15) was 91% (45.5% CR+45.5 PR). Patients treated with CIT (n=694) had an ORR of 68.7% (28.3% CR+40.4% PR). In conclusion, in a large international study we provide real world data regarding the selection and sequencing of treatment in CLL, charting a major shift in treatment patterns before and after the introduction of novel trargeted agents and confirming their efficacy even in high-risk CLL.

Background

Venetoclax is the first BCL-2 inhibitor approved for the treatment of patients with chronic lymphocytic leukemia (CLL) alone or in combination with anti-CD20 monoclonal antibodies (MoAbs). Initial studies have shown high efficacy of venetoclax monotherapy or in combination with rituximab with an overall response rate of 79-92% in patients with relapsed/refractory (R/R) CLL.

IntroductionTreatment of chronic phase (CP) chronic myeloid leukemia (CML) with tyrosine kinase inhibitors (TKIs) proved to be almost equally effective in young and elderly patients. Three TKIs, imatinib (IM), dasatinib (DAS) and nilotinib (NIL), are approved for frontline therapy in Italy. Choice of frontline TKI is based on a combined evaluation of patient's characteristics and expectations, with age usually playing a prominent role. However, to date, few data are available on patterns of TKI selection in very elderly patients.

Nucleophosmin (NPM1) gene has been heavily implicated in cancer pathogenesis both as a putative proto-oncogene and tumor suppressor gene. NPM1 is the most frequently mutated gene in acute myeloid leukemia (AML), while deletion of 5q, where NPM1 maps, is frequent in patients with myelodysplastic syndromes (MDS). We have previously shown that mice heterozygous for Npm1 (Npm1+/−) develop a hematologic syndrome with features of human MDS. Here we analyzed Npm1+/− mutants to determine their susceptibility to cancer. Npm1+/− mice displayed a greater propensity to develop malignancies compared with Npm1+/+ mice. The Npm1+/− cohort frequently developed hematologic malignancies of both myeloid and lymphoid origin with myeloid malignancies displaying the highest incidence. Malignant cells retained the wild-type allele with normal localization and expression of Npm1 at the protein level, suggesting that complete Npm1 loss is not a prerequisite for tumorigenesis. Our results conclusively demonstrate that Npm1 acts as a haploinsufficient tumor suppressor in the hematopoietic compartment.

Nucleophosmin (NPM1)gene has been heavily implicated in cancer pathogenesis both as a putative proto-oncogene and tumor suppressor gene. NPM1is the most frequently mutated gene in acute myeloid leukemia (AML), while deletion of 5q, where NPM1maps, is frequent in patients with myelodysplastic syndromes (MDS). We have previously shown that mice heterozygous for Npm1 (Npm1+/−) develop a hematologic syndrome with features of human MDS. Here we analyzed Npm1+/−mutants to determine their susceptibility to cancer. Npm1+/−mice displayed a greater propensity to develop malignancies compared with Npm1+/+mice. The Npm1+/−cohort frequently developed hematologic malignancies of both myeloid and lymphoid origin with myeloid malignancies displaying the highest incidence. Malignant cells retained the wild-type allele with normal localization and expression of Npm1 at the protein level, suggesting that complete Npm1loss is not a prerequisite for tumorigenesis. Our results conclusively demonstrate that Npm1acts as a haploinsufficient tumor suppressor in the hematopoietic compartment.

Nucleophosmin(NPM1) mutations in acute myeloid leukemia (AML) affect exon 12, but sporadically also exon 9 and 11, all causing changes at protein C-terminal end (loss of tryptophans and creation of a nuclear export signal-NES motif) that lead to aberrant cytoplasmic NPM1 (NPM1c+), detectable by immunohistochemistry. Combining immunohistochemistry and molecular analyses in 929 AML patients, we found non-exon 12 NPM1mutations in 5/387 (1.3%) NPM1c+ cases. Besides mutations in exon 9 (n=1) and exon 11 (n=1), novel mutations in exon 5 were discovered (n=3). One more exon 5 mutation was identified in additional 141 AML patients selected for wild-type NPM1exon 12. Furthermore, 3 NPM1rearrangements (i.e. NPM1/RPP30, NPM1/SETBP1, NPM1/CCDC28A) were detectedand characterized among 13,979AML samples screened by cytogenetic/FISH and RNA sequencing. Functional studies demonstrated that in AML cases the new NPM1 proteins harboured an efficient extra NES, either newly created or already present in the fusion partner, ensuring its cytoplasmic accumulation. Our findings support NPM1 cytoplasmic relocation as critical for leukemogenesis and reinforce the role of immunohistochemistry in predicting any AML-associated NPM1genetic lesions. Also, this study highlights the need for developing new specific assays for molecular diagnosis and monitoring of NPM1-mutated AML.

Mauro: Gilead: Consultancy, Research Funding; Jannsen: Consultancy, Research Funding; Shire: Consultancy, Research Funding; Abbvie: Consultancy, Research Funding; Roche: Consultancy, Research Funding. Coscia:Abbvie: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; Karyopharm Therapeutics: Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding. Varettoni:ABBVIE: Other: travel expenses; Roche: Consultancy; Janssen: Consultancy; Gilead: Other: travel expenses. Rossi:Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Honoraria, Other: Scientific advisory board; Janseen: Honoraria, Other: Scientific advisory board; Roche: Honoraria, Other: Scientific advisory board; Astra Zeneca: Honoraria, Other: Scientific advisory board. Gaidano:AbbVie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sunesys: Consultancy, Honoraria; Astra-Zeneca: Consultancy, Honoraria; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Mauro: Jannsen: Consultancy, Research Funding; Gilead: Consultancy, Research Funding; Abbvie: Consultancy, Research Funding; Shire: Consultancy, Research Funding; Roche: Consultancy, Research Funding. Coscia:Gilead: Membership on an entity's Board of Directors or advisory committees; Karyopharm Therapeutics: Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Membership on an entity's Board of Directors or advisory committees. Herishanu:Roche: Honoraria; Janssen: Honoraria; AbbVie: Honoraria. Varettoni:ABBVIE: Other: travel expenses; Roche: Consultancy; Gilead: Other: travel expenses; Janssen: Consultancy. Rigolin:AbbVie: Speakers Bureau; Gilead: Speakers Bureau; Gilead: Research Funding. Rossi:Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Honoraria, Other: Scientific advisory board; Janseen: Honoraria, Other: Scientific advisory board; Roche: Honoraria, Other: Scientific advisory board; Astra Zeneca: Honoraria, Other: Scientific advisory board. Gaidano:AbbVie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sunesys: Consultancy, Honoraria; Astra-Zeneca: Consultancy, Honoraria. Cuneo:Amgen: Honoraria; Abbvie: Honoraria, Speakers Bureau; Gilead: Honoraria, Speakers Bureau; Janssen: Honoraria, Speakers Bureau; Roche: Honoraria, Speakers Bureau. Foà:Roche: Consultancy, Speakers Bureau; Celltrion: Membership on an entity's Board of Directors or advisory committees; Abbvie: Consultancy, Speakers Bureau; Amgen Inc.: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen Inc.: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Shire: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Roche: Consultancy, Speakers Bureau; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Shire: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Abbvie: Consultancy, Speakers Bureau; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celltrion: Membership on an entity's Board of Directors or advisory committees.

Herishanu: Roche: Honoraria; AbbVie: Honoraria; Janssen: Honoraria. Simkovic:Roche: Honoraria; University Hospital Hradec Kralove: Employment; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Acerta: Consultancy, Honoraria. Mauro:Gilead: Consultancy, Research Funding; Shire: Consultancy, Research Funding; Abbvie: Consultancy, Research Funding; Jannsen: Consultancy, Research Funding; Roche: Consultancy, Research Funding. Coscia:Abbvie: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm Therapeutics: Research Funding. Scarfo:AstraZeneca: Honoraria; Janssen: Honoraria; AbbVie: Honoraria. Tedeschi:AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen spa: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Consultancy; AstraZeneca: Membership on an entity's Board of Directors or advisory committees; SUNESIS: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BeiGene: Honoraria. Gimeno Vázquez:JANSSEN: Consultancy, Speakers Bureau; Abbvie: Speakers Bureau. Assouline:F. Hoffmann-La Roche Ltd: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Speakers Bureau; Pfizer: Consultancy, Honoraria, Speakers Bureau. Levato:Novartis: Honoraria; Pfizer: Honoraria; Incyte: Honoraria; BMS: Honoraria. Rigolin:Gilead: Speakers Bureau; Gilead: Research Funding; AbbVie: Speakers Bureau. Loscertales:Janssen: Honoraria; Roche: Honoraria; AstraZeneca: Honoraria; AbbVie: Honoraria; Gilead: Honoraria. Ghia:Dynamo: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria, Research Funding; Acerta/AstraZeneca: Consultancy, Honoraria; ArQule: Consultancy, Honoraria; BeiGene: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Juno/Celgene: Consultancy, Honoraria; Sunesis: Consultancy, Honoraria, Research Funding; Novartis: Research Funding; Pharmacyclics LLC, an AbbVie Company: Consultancy; Gilead: Consultancy, Honoraria, Research Funding.

In high-risk acute leukemia patients undergoing HLA haploidentical T cell-depleted tranplantation, we demonstrated that adoptive immunotherapy with donor T regulatory cells (Tregs; 2x106/kg) co-infused with conventional T cells (Tcon; 1x106/kg ) provided significant protection from acute graft-versus-host disease (aGvHD) and was associated with an almost complete control of leukemia relapse (graft versus leukemia effect, GvL) (Di Ianni et al., Blood 2011; Martelli et al., Blood 2014; Ruggeri et al., ASH 2018). In the present study we investigated whether Tregs interact with bone marrow (BM) and peripheral blood (PB) dendritic cells (DCs) and whether such interaction is responsible for GvHD protection and GvL effect. Twenty six patients (median age 54 ; 20 AML; 4 ALL; 2 MDS) transplanted between July 2016 and April 2019 were evaluated up to one year after the transplant. BM and PB DCs (using CD123 for plasmocitoid DC-pDC; CD11c for myeloid DC-mDC; CD80/CD86 for costimulatory molecules) and T cells (CD3/CD4/CD8; CD4/CD25/CD127; CD28/PD-1/TIM3) were analysed by flow-cytometry. DCs were also sorted and analysed by RT-PCR for a panel of genes involved in activation (IL-6; TNF-a; IL-12; CCR7; NOTCH ligands) vs tolerigenic (TGF-beta; PD-1/PDL1; IDO; IL-10; ICOS) pathways. To study the effects of DCs on T cell proliferation, pre-activated (with GM-CSF at 50 ng/ml, IL-4 at 800 U/ml and TNF-a at 50 ng/ml for 18 hrs) BM and PB CD1c+DCs were co-cultured for 96 hrs with autologous CFSE labelled BM and PB CD3+ cells at a DC:CD3 ratio of 1:10. mDC numbers were significantly higher in BM than PB during the first 6 months after transplant. BM-derived mDCs expressed higher levels of the co-stimulatory receptor CD86. No differences emerged in pDCs. RT-PCR showed an activation signature in BM-DCs (significantly higher IL-6 level) and a tolerigenic signature in PB-DCs (significantly higher TGF-beta and PDL-1 levels). BM-derived CD8+T cells displayed a higher expression of the co-stimulatory receptor CD28 than PB-derived CD8+T cells (30.3±18.8 vs 9.2±4.9; p<0.05 ). In contrast, the expression of the immune checkpoint inhibitor PD-1 was significantly higher in both PB-derived CD4 (69%±29 vs 24±11) and CD8 (65±25 vs 4±3; p<0.05) T cells than BM-derived T lymphocytes. T cells from both BM and PB did not express the T cell exhaustion marker TIM-3. CD3/CFSE+-DCs co-cultures showed a T cell proliferation rate that was significantly higher in BM than in PB (25±7.2 vs 6.7±8.7; p<0.05). These data show that haploidentical transplantation with Treg/Tcon immunotherapy promotes the reconstitution of DCs with an activating signature in the BM and a tolerigenic signature in the PB. Human peripheral blood Tregs that are used for adoptive immunotherapy are largely CD45RO+ and express low level of CxCR4 bone marrow homing receptor. When infused in immunodeficient mice they migrate to the periphery (spleen, gut, liver) but are unable to home to the bone marrow (Ruggeri et al., ASH 2018). In conclusion, Tregs/DC interaction induce tolerance in the periphery (and may protect from GvHD). In the BM, in the absence of Tregs, DCs activate alloreactive Tcon and may favour killing of the leukemic targets. Therefore, Tregs/DC interactions may contribute to the separation between GvL effect and GvHD in the Treg based haploidentical transplantation.

Lund Winter: CaDo Biotechnology IvS: Employment. Stegmaier:Novartis: Research Funding; Rigel Pharmaceuticals: Consultancy. Dalby-Brown:CaDo Biotechnology IvS: Employment.