Uncovering the expression of circPVT1 in the extracellular vesicles of acute myeloid leukemia patients.

Extracellular vesicles (EVs) act as molecular mediators in the tumor microenvironment, by shuttling information contained within malignant cells and functioning as regulators of the immune system. Circular (circ)RNAs are characterized by a closed loop-like structure that makes them more stable in the extracellular milieu and suitable to be packaged inside EVs. circPVT1 (hsa_circ_0001821) showed an oncogenic role in several cancer types and immunosuppressive properties in myeloid and lymphoid cell subsets. In this study, we characterized EVs from acute myeloid leukemia (AML) patients in terms of size, concentrations, surface markers and circPVT1 cargo. We showed that circPVT1 is overexpressed by primary blast cells from newly-diagnosed AML patients compared with hematopoietic stem-progenitor cells and is released as cell-free RNA in the plasma. We isolated EVs from the plasma of AML patients and healthy subjects by size exclusion chromatography and characterized them by nanoparticle tracking analysis. EVs from patients' plasma are larger compared with those from healthy subjects and their surface profile is characterized by higher levels of the leukemic cell markers CD133, CD105, CD49e and other immune-related epitopes, with differences according to AML molecular profile. Moreover, digital PCR analysis revealed that circPVT1 is more abundant inside EVs from the plasma of AML patients compared with healthy subjects. Our findings provide new insights on the features and content of AML EVs and suggest a role of circPVT1 in the crosstalk between AML cells and the tumor microenvironment.

Etoposide plus cytarabine versus cyclophosphamide or melphalan in busulfan-based preparative regimens for autologous stem cell transplantation in adults with acute myeloid leukemia in first complete remission: a study from the Acute Leukemia Working Party of the EBMT.

We retrospectively compared the impact of the conditioning regimen in adult patients with acute myeloid leukemia (AML) in first complete remission (CR1) that received high-dose myeloablative chemotherapy followed by autologous stem cell transplantation (ASCT) from 2010 to 2021 with either high-dose cytarabine, etoposide and busulfan (BEA), busulfan with cyclophosphamide (BUCY) or busulfan and high-dose melphalan (BUMEL) registered in the EBMT database. Overall 1560 patients underwent ASCT, of which 156, 1143 and 261 received BEA, BUCY and BUMEL, respectively. Compared to BUCY and BUMEL, BEA patients were younger (p < 0.001) and less frequently had NPM1 mutations (p = 0.03). Transplant outcomes at 5 years with BEA, BUCY and BUMEL were: cumulative incidence of relapse 41.8%, 46.6% and 51.6%; non-relapse mortality (NRM) 1.5%, 5.2% and 7.3%; probability of leukemia-free survival (LFS) 56.7%, 48.2% and 41.1%; and overall survival (OS) 71.3%, 62.3% and 56%, respectively. In multivariable analysis the BEA regimen showed significant improvement in OS compared to BUCY (hazard ratio [HR] 0.65; 95% CI, 0.42-0.83; p = 0.048) and BUMEL (HR 0.59; 95% CI, 0.37-0.94; p = 0.029). In conclusion, high-dose myeloablative combination chemotherapy with BEA offered improved outcomes compared to classical BUCY or BUMEL in patients with AML in CR1 undergoing ASCT.

Lenalidomide plus rituximab for the initial treatment of frail older patients with DLBCL: the FIL_ReRi phase 2 study.

Treatment of diffuse large B-cell lymphoma (DLBCL) in older patients is challenging, especially for those who are not eligible for anthracycline-containing regimens. Fondazione Italiana Linfomi (FIL) started the FIL_ReRi study, a 2-stage single-arm trial to investigate the activity and safety of the chemo-free combination of rituximab and lenalidomide (R2) in ≥70-year-old untreated frail patients with DLBCL. Frailty was prospectively defined using a simplified geriatric assessment tool. Patients were administered a maximum of 6 28-day cycles of 20 mg oral lenalidomide from days 2 to 22 and IV rituximab 375 mg/m2 on day 1, with response assessment after cycles 4 and 6. Patients with partial response or complete response (CR) at cycle 6 were administered lenalidomide 10 mg/d from days 1 to 21 for every 28 cycles for a total of 12 cycles or until progression or unacceptable toxicity. The primary end point was the overall response rate (ORR) after cycle 6; the coprimary end point was the rate of grade 3 or 4 extrahematological toxicity. The ORR was 50.8%, with 27.7% CR. After a median follow-up of 24 months, the median progression-free survival was 14 months, and the 2-year duration of response was 64%. Thirty-four patients experienced extrahematological toxicity according to the National Cancer Institute Common Terminology Criteria for Adverse Events grade ≥3. The activity of the R2 combination was observed in a significant proportion of subjects, warranting further exploration of a chemo-free approach in frail older patients with DLBCL. This trial was registered at EudraCT as #2015-003371-29 and clinicaltrials.gov as #NCT02955823.

Allogeneic hematopoietic cell transplantation for patients with AML aged 70 years or older in first remission. A study from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation (EBMT).

Accessibility to allogeneic hematopoietic cell transplantation (HCT) programs for older patients is growing constantly. We report on the clinical outcomes of a group of 701 adults aged ≥70 years, with acute myeloid leukemia (AML) in first complete remission (CR1), who received a first HCT, from HLA-matched sibling donors (MSD), 10/10 HLA-matched unrelated donors (UD), 9/10 HLA-mismatched unrelated donors (mUD) or haploidentical (Haplo) donors. The 2-year overall survival (OS) was 48.1%, leukemia-free survival (LFS) 45.3%, relapse incidence (RI) 25.2%, non-relapse mortality (NRM) 29.5% and GVHD-free, relapse-free survival (GRFS), 33.4%. Compared to MSD, patients transplanted from Haplo and UD presented lower RI (HR 0.46, 95% CI 0.25-0.8, p = 0.02 and HR 0.44, 95% CI: 0.28-0.69, p = 0.001, respectively); this translated into prolonged LFS for Haplo (HR 0.62, 95% CI: 0.39-0.99, p = 0.04). Patients transplanted from mUD exhibited the highest NRM incidence (HR 2.33, 95% CI: 1.26-4.31, p = 0.007). HCT in selected adult CR1 AML patients >70 years is feasible and could be associated with good clinical outcomes. Prospective clinical trials are warranted.

New Horizons in Immunology and Immunotherapy of Acute Leukemias and Related Disorders.

Accumulating data have shown that molecular aberrations have the potential to trigger the development of acute leukemia, and that the routine application of novel molecular biology technologies has facilitated the development of investigational drugs which target driver genetic mutations [...].

AVALON: The Italian cohort study on real-life efficacy of hypomethylating agents plus venetoclax in newly diagnosed or relapsed/refractory patients with acute myeloid leukemia.

BACKGROUND: Venetoclax in combination with hypomethylating agents (HMA) is revolutionizing the therapy of acute myeloid leukemia (AML). However, evidence on large sets of patients is lacking, especially in relapsed or refractory leukemia. METHODS: AVALON is a multicentric cohort study that was conducted in Italy on patients with AML who received venetoclax-based therapies from 2015 to 2020. The study was approved by the ethics committee of the participating institution and was conducted in accordance with the Declaration of Helsinki. The effectiveness and toxicity of venetoclax + HMA in 190 (43 newly diagnosed, 68 refractory, and 79 relapsed) patients with AML are reported here. RESULTS: In the newly diagnosed AML, the overall response rate and survival confirmed the brilliant results demonstrated in VIALE-A. In the relapsed or refractory AML, the combination demonstrated a surprisingly complete remission rate (44.1% in refractory and 39.7% in relapsed evaluable patients) and conferred to treated patients a good expectation of survival. Toxicities were overall manageable, and most incidents occurred in the first 60 days of therapy. Infections were confirmed as the most common nonhematologic adverse event. CONCLUSIONS: Real-life data show that the combination of venetoclax and HMA offers an expectation of remission and long-term survival to elderly, newly diagnosed patients, and to relapsed or chemoresistant AML, increasing the chance of cure through a different mechanism of action. The venetoclax + HMA combination is expected to constitute the base for triplet combinations and integration of target therapies. Our data contribute to ameliorate the understanding of venetoclax + HMA effectiveness and toxicities in real life.

Autologous stem cell transplantation (ASCT) for acute myeloid leukemia in patients in first complete remission after one versus two induction courses: A study from the ALWP of the EBMT.

BACKGROUND: Achieving complete remission (CR) is the main goal in AML treatment and a prerequisite for successful autologous stem cell transplantation (ACT). METHODS: Comparing results of peripheral blood ACT in patients with AML in CR1 attained following 1 versus 2 chemotherapy courses transplanted in 2000-2019. RESULTS: Patients 1532 (84%) with one and 293 (16%) patients with two induction chemotherapies courses (a total of 1825 patients) were included in the study. Follow-up was 7.9 (95% CI: 7.4-8.4) and 7.7 (95% CI: 7.0-8.6) years (p = 0.8). Time from diagnosis to ACT was 4.7 (range, 3.9-5.8) versus 5.7 (range, 4.7-7.1) months (p < 0.001), respectively. Leukemia free survival (LFS) and overall survival (OS) at 5 years were inferior for patients achieving CR1 with 2 versus 1 course of chemotherapy: 26.6% versus 41.7% (HR = 1.42 [95% CI: 1.22-1.66], p < 0.001) and 36.2% versus 53.3%, (HR = 1.48 [95% CI: 1.25-1.75], p < 0.001), and 5-year relapse incidence (RI) was higher: 67.2% versus 52.3%, (HR = 1.46 [95% CI: 1.25-1.72], p < 0.001). Five-year non-relapse mortality (NRM) was 6.2% versus 6.0% for patients with 2 versus 1 chemotherapy courses, and did not differ significantly (HR = 1.31 [95% CI: 0.81-2.10], p = 0.27). CONCLUSIONS: LFS and OS were inferior and relapse rate was higher in AML patients who received two inductions chemotherapy courses to reach CR1 before being autografted. AML patients who required 2 induction courses to achieve remission, may be offered allogeneic transplantation rather than an autologous one in an attempt to reduce their high RI and improve outcomes.

Lack of efficacy of convalescent plasma in COVID-19 patients with concomitant hematological malignancies: An Italian retrospective study.

A multicenter retrospective study was designed to assess clinical outcome of COVID-19 in patients with hematological malignancies (HM) following treatment with anti-SARS-CoV-2 convalescent plasma (CP) or standard of care therapy. To this aim, a propensity score matching was used to assess the role of non-randomized administration of CP in this high-risk cohort of patients from the Italian Hematology Alliance on COVID-19 (ITA-HEMA-COV) project, now including 2049 untreated control patients. We investigated 30- and 90-day mortality, rate of admission to intensive care unit, proportion of patients requiring mechanical ventilatory support, hospitalization time, and SARS-CoV-2 clearance in 79 CP recipients and compared results with 158 propensity score-matched controls. Results indicated a lack of efficacy of CP in the study group compared with the untreated group, thus confirming the negative results obtained from randomized studies in immunocompetent individuals with COVID-19. In conclusion, this retrospective analysis did not meet the primary and secondary end points in any category of immunocompromized patients affected by HM.

Spotlights on the latest opinions on identification, prevention, and management of newer CoV-2 variants: A roundup appraisal on innovative ideas and designer vaccines for Omicron.

Although mass vaccination combined with some other preventative strategies and lockdown was associated with some early signs that COVID-19 infection might be fading away, the over 35 sites mutated new South African variant, "Omicron", emerged almost globally. Certain predisposed hosts may develop severe inflammatory thrombotic or mild long-Covid conditions due to this variant, which depletes T-cells, neutralizes antibodies circulating in the body, and coincidentally induces hypercoagulability. The surge of Omicron combined with Delta variants may confer unresponsiveness to the currently available vaccines even when the second dose is given up to 90 days. A drop in the antibody levels by 30 % has been identified in omicron-infected individuals, and one in five people is resistant to antibody treatment. This poses major concerns in the transmissibility rate of this new variant, even in a heavy mass vaccinated environment. This heavily mutated Omicron with other spike sites facilitates viral entry into the cells through conformational changes, irrespective of circulating neutralising antibody. Based on this consideration, we believe that speeding up mixed-matched vaccines with higher T-cell stimulation ability may improve the current situation. Moreover, large orders for antiviral drugs and monoclonal antibodies that could tackle Omicron combined with other variants may be valuable. The use of free polyclonal antibody donations and, hopefully, T-cell immunotherapy, may represent further breakthrough therapeutic interventions. However, Omicron infection is relatively milder than the ongoing Delta variant but is extremely contagious, and therefore the development of novel interventions is highly demanding.

Secondary infections worsen the outcome of COVID-19 in patients with hematological malignancies: A report from the ITA-HEMA-COV.

The impact of secondary infections (SI) on COVID-19 outcome in patients with hematological malignancies (HM) is scarcely documented. To evaluate incidence, clinical characteristics, and outcome of SI, we analyzed the microbiologically documented SI in a large multicenter cohort of adult HM patients with COVID-19. Among 1741 HM patients with COVID-19, 134 (7.7%) had 185 SI, with a 1-month cumulative incidence of 5%. Median time between COVID-19 diagnosis and SI was 16 days (IQR: 5-36). Acute myeloid leukemia (AML) and lymphoma/plasma cell neoplasms (PCN) were more frequent diagnoses in SI patients compared to patients without SI (AML: 14.9% vs. 7.1%; lymphoma/PCN 71.7% vs. 65.3%). Patients with SI were older (median age 70 vs. 66 years, p = 0.002), with more comorbidities (median Charlson Comorbidity Index 5 vs. 4, p < 0.001), higher frequency of critical COVID-19 (19.5% vs. 11.5%, p = 0.046), and more frequently not in complete remission (75% vs. 64.7% p = 0.024). Blood and bronchoalveolar lavage were the main sites of isolation for SI. Etiology of infections was bacterial in 80% (n = 148) of cases, mycotic in 9.7% (n = 18) and viral in 10.3% (n = 19); polymicrobial infections were observed in 24 patients (18%). Escherichia coli represented most of Gram-negative isolates (18.9%), while coagulase-negative Staphylococci were the most frequent among Gram-positive (14.2%). The 30-day mortality of patients with SI was higher when compared to patients without SI (69% vs. 15%, p < 0.001). The occurrence of SI worsened COVID-19 outcome in HM patients. Timely diagnosis and adequate management should be considered to improve their prognosis.

Measurable residual disease (MRD) status before allogeneic hematopoietic cell transplantation impact on secondary acute myeloid leukemia outcome. A Study from the Acute Leukemia Working Party (ALWP) of the European society for Blood and Marrow Transplantation (EBMT).

Measurable residual disease (MRD) assessment before allogeneic hematopoietic cell transplantation (HCT) may help physicians to identify a subgroup of patients at high risk of relapse for de novo acute myeloid leukemia (AML) but its relevance among patients affected by secondary AML (sAML) is still unknown. We assessed the impact of MRD among 318 adult patients with sAML who received an allogeneic HCT in first complete remission. At the time of HCT, a total of 208 (65%) patients achieved MRD negativity, while 110 (35%) had positive MRD. 2-year overall survival (OS) was 58.8 % (95% CI 52.2-64.9) with leukemia-free survival (LFS) of 50.0 % (95% CI 43.7-56.1), relapse incidence of 34.2% (95% CI 28.4-40.1) and non-relapse mortality (NRM) of 23.3 % (95% CI 19-27.7) for the entire cohort. In multivariate analysis, HCT recipients with KPS ≥ 90 experienced less disease recurrence (HR 0.61, 95% CI 0.4-0.94) with better LFS (HR 0.63, 95% CI 0.44-0.89) and OS (HR 0.58, 95% CI 0.39-0.86). There were no differences in major clinical endpoints between patients with MRD-positive and MRD-negative status at the time of HCT. Pre-transplantation assessment of MRD was not informative on post-HCT outcomes in this retrospective registry-based analysis among patients affected by sAML.

In uveal melanoma Gα-protein GNA11 mutations convey a shorter disease-specific survival and are more strongly associated with loss of BAP1 and chromosomal alterations than Gα-protein GNAQ mutations.

BACKGROUND AND AIM OF THE STUDY: Mutations in the Gα-genes GNAQ and GNA11 are found in 85-90% of uveal melanomas (UM). Aim of the study is to understand whether the mutations in both genes differentially affect tumor characteristics and outcome and if so, to identify potential mechanisms. METHODS: We analyzed the association between GNAQ and GNA11 mutations with disease-specific survival, gene expression profiles, and cytogenetic alterations in 219 UMs. We used tandem-affinity-purification, mass spectrometry and immunoprecipitation to identify protein interaction partners of the two G-proteins and analyzed their impact on DNA-methylation. RESULTS: GNA11 mutation was associated with: i) an increased frequency of loss of BRCA1-associated protein 1 (BAP1) expression (p = 0.0005), ii) monosomy of chromosome 3 (p < 0.001), iii) amplification of chr8q (p = 0.038), iv) the combination of the latter two (p = 0.0002), and inversely with v) chr6p gain (p = 0.003). Our analysis also showed a shorter disease-specific survival of GNA11-mutated cases as compared to those carrying a GNAQ mutation (HR = 1.97 [95%CI 1.12-3.46], p = 0.02). GNAQ and GNA11 encoded G-proteins have different protein interaction partners. Specifically, the Tet Methylcytosine Dioxygenase 2 (TET2), a protein that is involved in DNA demethylation, physically interacts with the GNAQ protein but not with GNA11, as confirmed by immunoprecipitation analyses. High-risk UM cases show a clearly different DNA-methylation pattern, suggesting that a different regulation of DNA methylation by the two G-proteins might convey a different risk of progression. CONCLUSIONS: GNA11 mutated uveal melanoma has worse prognosis and is associated with high risk cytogenetic, mutational and molecular tumor characteristics that might be determined at least in part by differential DNA-methylation.

Improved outcome of patients with graft-versus-host disease after allogeneic hematopoietic cell transplantation for hematologic malignancies over time: an EBMT mega-file study.

Acute graft-versus-host disease (aGvHD) remains a major threat to successful outcome following allogeneic hematopoietic cell transplantation though advances in prophylaxis and supportive care have been made. The aim of this study is to test whether the incidence and mortality of aGvHD have decreased over time. 102,557 patients with a median age of 47.6 years and with malignancies after first allogeneic sibling or unrelated donor (URD) transplant were studied in the following periods: 1990-1995, 1996-2000, 2001-2005, 2006-2010 and 2011-2015. Findings: 100-day incidences of aGvHD grades II-IV decreased from 40% to 38%, 32%, 29% and 28%, respectively, over calendar time (P<0.001). In multivariate analysis URD, not in complete remission (CR) at transplant or untreated, and female donor for male recipient were factors associated with increased risk whereas the use of ATG/alemtuzumab decreased aGvHD incidence. Median follow-up was 214, 169, 127, 81 and 30 months, respectively, for the periods analyzed. Three-year-survival after aGvHD grades II-IV increased significantly from 38% to 40%, 43%, 44%, and 45%, respectively. In multivariate analysis URD, not in CR at transplant, peripheral blood as stem cell source, female donor for male recipient, and the use of ATG/alemtuzumab were associated with increased mortality whereas reduced-intensity conditioning was linked to lower mortality. Mortality increased with increasing patient age but decreased in the recent cohorts. Our analysis demonstrates that aGvHD has decreased over recent decades and also that the survival rates of patients affected with aGvHD has improved.

ELN2017 risk stratification improves outcome prediction when applied to the prospective GIMEMA AML1310 protocol.

The 2017 version of the European LeukemiaNet (ELN) recommendations, by integrating cytogenetics and mutational status of specific genes, divides patients with acute myeloid leukemia into 3 prognostically distinct risk categories: favorable (ELN2017-FR), intermediate (ELN2017-IR), and adverse (ELN2017-AR). We performed a post hoc analysis of the GIMEMA (Gruppo Italiano Malattie EMatologiche dell'Adulto) AML1310 trial to investigate the applicability of the ELN2017 risk stratification to our study population. In this trial, after induction and consolidation, patients in complete remission were to receive an autologous stem cell transplant (auto-SCT) if categorized as favorable risk or an allogeneic stem cell transplant (allo-SCT) if adverse risk. Intermediate-risk patients were to receive auto-SCT or allo-SCT based on the postconsolidation levels of measurable residual disease as measured by using flow cytometry. Risk categorization was originally conducted according to the 2009 National Comprehensive Cancer Network recommendations. Among 500 patients, 445 (89%) were reclassified according to the ELN2017 criteria: ELN2017-FR, 186 (41.8%) of 455; ELN2017-IR, 179 (40.2%) of 445; and ELN2017-AR, 80 (18%) of 455. In 55 patients (11%), ELN2017 was not applicable. Two-year overall survival (OS) was 68.8%, 51.3%, 45.8%, and 42.8% for the ELN2017-FR, ELN2017-IR, ELN2017-not classifiable, and ELN2017-AR groups, respectively (P < .001). When comparing the 2 different transplant strategies in each ELN2017 risk category, a significant benefit of auto-SCT over allo-SCT was observed among ELN2017-FR patients (2-year OS of 83.3% vs 66.7%; P = .0421). The 2 transplant procedures performed almost equally in the ELN2017-IR group (2-year OS of 73.9% vs 70.8%; P = .5552). This post hoc analysis of the GIMEMA AML1310 trial confirms that the ELN2017 classification is able to accurately discriminate patients with different outcomes and who may benefit from different transplant strategies. This trial was registered as EudraCT number 2010-023809-36 and at www.clinicaltrials.gov as #NCT01452646.