MicroRNA profiling of paediatric AML with FLT-ITD or MLL-rearrangements: Expression signatures and in vitro modulation of miR-221-3p and miR-222-3p with BRD4/HATs inhibitors.

Novel therapeutic strategies are needed for paediatric patients affected by Acute Myeloid Leukaemia (AML), particularly for those at high-risk for relapse. MicroRNAs (miRs) have been extensively studied as biomarkers in cancer and haematological disorders, and their expression has been correlated to the presence of recurrent molecular abnormalities, expression of oncogenes, as well as to prognosis/clinical outcome. In the present study, expression signatures of different miRs related both to presence of myeloid/lymphoid or mixed-lineage leukaemia 1 and Fms like tyrosine kinase 3 internal tandem duplications rearrangements and to the clinical outcome of paediatric patients with AML were identified. Notably, miR-221-3p and miR-222-3p resulted as a possible relapse-risk related miR. Thus, miR-221-3p and miR-222-3p expression modulation was investigated by using a Bromodomain­containing protein 4 (BRD4) inhibitor (JQ1) and a natural compound that acts as histone acetyl transferase inhibitor (curcumin), alone or in association, in order to decrease acetylation of histone tails and potentiate the effect of BRD4 inhibition. JQ1 modulates miR-221-3p and miR-222-3p expression in AML with a synergic effect when associated with curcumin. Moreover, changes were observed in the expression of CDKN1B, a known target of miR-221-3p and miR-222-3p, increase in apoptosis and downregulation of miR-221-3p and miR-222-3p expression in CD34+ AML primary cells. Altogether, these findings suggested that several miRs expression signatures at diagnosis may be used for risk stratification and as relapse prediction biomarkers in paediatric AML outlining that epigenetic drugs, could represent a novel therapeutic strategy for high-risk paediatric patients with AML. For these epigenetic drugs, additional research for enhancing activity, bioavailability and safety is needed.

Immunomodulatory Effects of IFNα on T and NK Cells in Chronic Myeloid Leukemia Patients in Deep Molecular Response Preparing for Treatment Discontinuation.

A deep and stable molecular response (DMR) is a prerequisite for a successful treatment-free remission (TFR) in chronic myeloid leukemia (CML). In order to better identify and analyze potential candidates of successful TFR, we examined the phenotypic and functional host immune compartment in DMR patients who had received TKI treatment only (TKI-only) or had been previously treated with interferon-alpha (IFNα + TKI) or had received IFNα treatment only (IFNα-only). The T/NK-cell subset distribution, NK- and T-cell cytokine production, activation and maturation markers were measured in 44 patients in DMR treated with IFNα only (9), with IFNα + TKI (11) and with TKI-only (24). IFNα + TKI and TKI-only groups were eligible to TKI discontinuation according to the NCCN and ESMO guidelines (stable MR4 for more than two years). In IFNα-treated patients, we documented an increased number of lymphocytes capable of producing IFNγ and TNFα compared to the TKI-only group. In INFα + TKI patients, the percentage of NKG2C expression and its mean fluorescence intensity were significantly higher compared to the TKI-only group and to the INFα-only group in the CD56dim/CD16+ NK cell subsets (INFα + TKI vs. TKI-only p = 0.041, p = 0.037; INFα + TKI vs. INFα-only p = 0.03, p = 0.033, respectively). Furthermore, in INFα-only treated patients, we observed an increase of NKp46 MFI in the CD56bright/CD16- NK cell subset that becomes significant compared to the INFα + TKI group (p = 0.008). Our data indicate that a previous exposure to IFNα substantially and persistently modified the immune system of CML patients in memory T lymphocytes, differentiated NKG2C+ "long-lived" NK cells responses, even years after the last IFNα contact.

Brentuximab vedotin in combination with bendamustine in pediatric patients or young adults with relapsed or refractory Hodgkin lymphoma.

Although children and young adults with Hodgkin's lymphoma usually have a favorable prognosis, patients with primary refractory disease and some subsets of relapsed patients still have a dismal outcome. Brentuximab vedotin (BV) in combination with bendamustine may represent a suitable salvage therapy; data on 32 patients aged less than 25 years were retrospectively analyzed. Patients received up to six cycles of treatment of BV 1.8 mg/kg on day 1 and bendamustine 90-120 mg/m2 on days 2 and 3. At the end of treatment, the overall response rate was 81%. The 3-year overall and progression-free survivals are 78.1% and 67%, respectively.

Bosutinib in the real-life treatment of chronic myeloid leukemia patients aged >65 years resistant/intolerant to previous tyrosine-kinase inhibitors.

To evaluate the role of bosutinib in elderly patients aged >65 years with chronic myeloid leukemia (CML), a real-life cohort of 101 chronic-phase CML patients followed up in 23 Italian centers and treated with bosutinib in second or a subsequent line was retrospectively evaluated. Starting dose of bosutinib was 500 mg/day in 25 patients (24.8%), 400 mg/day in 7 patients (6.9%), 300 mg/day in 33 patients (32.7%), 200 mg/day in 34 patients (33.6%), and 100 mg/day in 2 patients (2.0%). Grade 3/4 hematological toxicity occurred in 7/101 patients (6.9%) and grade 3/4 extra-hematological toxicity in 19/101 patients (18.8%). Permanent bosutinib discontinuation due to toxicity was needed in 12 patients (11.9%). Among the 96 patients evaluable for response, 74 (77.0%) achieved a complete cytogenetic response (CCyR), while 64 of these 74 patients in CCyR (66.6% of all 96 evaluable patients) also achieved a molecular response (MR) (major MR [MR 3.0] in 21 [21.8%], deep MR [MR 4.0/4.5] in 43 [44.8%]). The 3-year event-free survival and overall survival of the whole patients' cohort from bosutinib start were 60.9% (CI 95% 49.3-72.5) and 86.4% (CI 95% 77.2-95.6), respectively. Our real-life data show that bosutinib is effective, with a favorable safety profile, also in elderly patients with important comorbidities and resistance and/or intolerance to previous tyrosine-kinase inhibitor treatments. As a consequence, it could play a significant role in current clinical practice for frail patients.

Clinical and Prognostic Features of Essential Thrombocythemia: Comparison of 2001 WHO Versus 2008/2016 WHO Criteria in a Large Single-center Cohort.

BACKGROUND: According to 2008/2016 classification of the World Health Organization (WHO), a platelet (PLT) count ≥ 450 × 109/L, reduced from the previously published WHO 2001 indicated level ≥ 600 × 109/L, was considered the new PLT threshold for the diagnosis of essential thrombocythemia (ET). PATIENTS AND METHODS: To validate this important diagnostic change in a setting of current clinical practice, we retrospectively analyzed clinical and hematologic features at diagnosis and during follow-up of 162 patients with ET, diagnosed in our center from January 2008 to December 2017. We subdivided patients according to PLT value at baseline into Group A (PLT ≥ 600 × 109/L) (124 patients; 76.5%) and Group B (PLT ≥ 450 × 109/L < 600 × 109/L) (38 patients; 23.5%). RESULTS: Among clinical features, only the median value of leukocytes (P < .001) was significantly higher in Group A. Cytostatic treatment was administered in 103 patients, with a significantly higher rate in patients of group A (P < .001). After a median follow-up of 42.4 months (interquartile range, 22.1-70.6 months), 8 thrombotic events were recorded in the entire cohort, without differences between the 2 groups (P = .336). The 5-year overall survival (OS) of the entire cohort was 96.9% (95% confidence interval, 92.6%-100%), without differences between the 2 groups (P = .255). CONCLUSIONS: Our data indicate a substantial homogeneity among patients with ET regardless of the PLT count at diagnosis, thus confirming the usefulness of the 2008/2016 WHO diagnostic criteria.

Balanced and unbalanced chromosomal translocations in myelodysplastic syndromes: clinical and prognostic significance.

Prognostic role of chromosomal translocations (CT) in myelodysplasia (MDS) was retrospectively analyzed in 77 patients from GROM-L registry. Forty (51.9%) balanced, 28 (36.4%) unbalanced and 9 (11.7%) concomitant balanced and unbalanced CT were identified. Five-year overall survival (OS) of the entire cohort was 34.5% (CI 95% 22.5-46.5). Five-year OS of patients with unbalanced CT was significantly shorter than that of patients carrying balanced CT [22.3% (CI 95% 4.0-40.6) vs 44.0% (CI 95% 26.7-61.3) (p = 0.042)]. Five-year OS of patients with CT included in complex karyotype (CK) was significantly shorter than that of patients with isolated CT or CT with another abnormality [5.5% (CI 95% 0-15.7) vs 42.9% (CI 95% 21.3-64.5) and vs 4% (CI 95% 31.6-79.2) (p < 0.001)]. Presence of CT in MDS characterizes a more aggressive outcome only when associated with CK.

Peripherally inserted central catheters in allogeneic hematopoietic stem cell transplant recipients.

BACKGROUND: Central venous catheters (CVC) are essential for the management of patients with hematologic malignancies, facilitating chemotherapy infusion, antibiotics, parenteral nutrition, blood products, and blood samples collection. In this population, peripherally inserted central catheters (PICC) seem to be associated with lower complications, compared with conventional percutaneously inserted devices (CICC). Data on the PICC in allogeneic hematopoietic stem cell recipients (allo-HSCT) are limited. METHODS: We have prospectively evaluated the safety and efficacy of 100 polyurethanes or silicone PICC, inserted into 100 adult allo-HSCT recipients, at the Hematology of Sapienza University of Rome (Italy), between October 2012 and August 2017. RESULTS: The median duration of PICC placement was 117 days. Overall, 68% of patients maintained the device for the entire transplant procedure and PICC were removed after day 100 from allo-HSCT; of these, 44% did not experienced any PICC-related complications. Catheter-related bloodstream infections (CRBSI) occurred in 32% of patients (2.5/1000 PICC days), associated with thrombosis in 8 cases. CRBSI were observed in 42% of patients with polyurethane and 20% with silicone PICC (p = 0.02). Catheter-related thrombosis occurred in 9% of patients, never requiring anticipated PICC removal. Mechanical complications occurred in 15% of cases (1.2/1000 PICC days). On the whole, adverse events were manageable and did not affect transplant outcome. No deaths related to PICC-complications were observed. CONCLUSIONS: PICC are a safe and reliable long-term venous access in allo-HSCT recipients.

Incidence of Clinically Significant (≤10 g/dL) Late Anemia in Elderly Patients with Newly Diagnosed Chronic Myeloid Leukemia Treated with Imatinib.

BACKGROUND: In elderly patients with chronic myeloid leukemia (CML) responsive to imatinib, the incidence of clinically significant (CS) late chronic anemia is still unknown. MATERIALS AND METHODS: To highlight this issue, we revised retrospectively 81 CML patients aged >60 years treated at our Institution with front-line imatinib for at least 24 months in durable complete cytogenetic response (CCyR). CS late chronic anemia was defined as the presence of persistent (>6 months) and otherwise unexplained Hb levels ≤10 g/dL, which occurred >6 months from imatinib start. RESULTS: A condition of CS late chronic anemia occurred in 22 out of 81 patients (27.2%) at different intervals from imatinib start. Seven out of 22 patients (31.8%) needed packed red cell transfusions during the follow-up. At diagnosis, patients who developed CS late chronic anemia were significantly older and had a lower Hb median level. Six out of 22 patients with CS late chronic anemia received subcutaneous recombinant alpha-erythropoietin (EPO) at the standard dosage of 40,000 IU weekly: all 6 patients achieved an erythroid response. A significantly worse event-free survival (EFS) in patients with untreated CS late chronic anemia was observed (p = 0.012). CONCLUSIONS: CS late chronic anemia during long-term treatment with imatinib is a common complication in responsive elderly patients, with worse EFS if untreated. Results with EPO are encouraging, but larger studies are warranted to define its role.

Key Role of the CD56lowCD16low Natural Killer Cell Subset in the Recognition and Killing of Multiple Myeloma Cells.

Natural Killer (NK) cells play a pivotal role in the immunosurveillance of Multiple Myeloma (MM), but it is still undefined whether the NK cell functional properties underlying their protective activity against MM are confined to distinct NK cell populations. Interestingly, herein we report that the CD56lowCD16low NK cell subset displayed higher cytolytic activity compared to the other NK cell subsets (i.e., CD56highCD16+/-, CD56lowCD16high) against MM cells and its activity was impaired in MM patients. Decreased DNAM-1 expression levels were observed on the CD56lowCD16low NK cells during MM progression. Evaluating NK cell subset frequency after autologous hematopoietic stem cell transplantation, we found that CD56lowCD16low NK cells recovered earlier after transplantation. Overall, our data denote a key role of CD56lowCD16low subpopulation in the killing of MM cells and suggest that the reconstitution of CD56lowCD16low subpopulation after HSCT could be a useful approach of adoptive immunotherapy in the treatment of relapsed/refractory MM patients.

MICA-129 Dimorphism and Soluble MICA Are Associated With the Progression of Multiple Myeloma.

Natural killer (NK) cells are immune innate effectors playing a pivotal role in the immunosurveillance of multiple myeloma (MM) since they are able to directly recognize and kill MM cells. In this regard, among activating receptors expressed by NK cells, NKG2D represents an important receptor for the recognition of MM cells, being its ligands expressed by tumor cells, and being able to trigger NK cell cytotoxicity. The MHC class I-related molecule A (MICA) is one of the NKG2D ligands; it is encoded by highly polymorphic genes and exists as membrane-bound and soluble isoforms. Soluble MICA (sMICA) is overexpressed in the serum of MM patients, and its levels correlate with tumor progression. Interestingly, a methionine (Met) to valine (Val) substitution at position 129 of the α2 heavy chain domain classifies the MICA alleles into strong (MICA-129Met) and weak (MICA-129Val) binders to NKG2D receptor. We addressed whether the genetic polymorphisms in the MICA-129 alleles could affect MICA release during MM progression. The frequencies of Val/Val, Val/Met, and Met/Met MICA-129 genotypes in a cohort of 137 MM patients were 36, 43, and 22%, respectively. Interestingly, patients characterized by a Val/Val genotype exhibited the highest levels of sMICA in the sera. In addition, analysis of the frequencies of MICA-129 genotypes among different MM disease states revealed that Val/Val patients had a significant higher frequency of relapse. Interestingly, NKG2D was downmodulated in NK cells derived from MICA-129Met/Met MM patients. Results obtained by structural modeling analysis suggested that the Met to Val dimorphism could affect the capacity of MICA to form an optimal template for NKG2D recognition. In conclusion, our findings indicate that the MICA-129Val/Val variant is associated with significantly higher levels of sMICA and the progression of MM, strongly suggesting that the usage of soluble MICA as prognostic marker has to be definitely combined with the patient MICA genotype.