Missense mutations in the PML/RAR alpha ligand binding domain in ATRA-resistant As2O3 sensitive relapsed acute promyelocytic leukemia

Background and Objectives. Acute promyelocytic leukemia is characterized by the chromosomal translocation t(15;17) which yields the fusion product PML/RAR alpha. Art-trans retinoic acid probably induces differentiation of atypical promyelocytes and clinical remission in APL patients by binding to the ligand binding domain (LBD) of the RAR alpha portion of the PML-RAR alpha chimeric protein. Structural alterations of the LED of the PML/RAR alpha have been revealed in ATRA-resistant APL cell lines and in a few APL patients with acquired clinical resistance to ATRA therapy. Two APL relapsed patients with clinical resistance to ATRA therapy were evaluated for the presence of nucleotide mutations in the LED of PML/RAR alpha gene and then treated with arsenic trioxide (As2O3). Design and Methods. DNA fragments from the LED of the PML/RAR alpha: chimeric transcript were obtained by reverse-transcribed polymerase chain reaction. Direct sequencing was performed by an unambiguous bidirectional automatic analysis. Samples representative of APL onset and relapse were analyzed from both patients. Results. In both patients, at the ATRA-resistant relapse, a missense point mutation in the LED of the PML/RAR alpha gene was found. The mutations, absent at APL onset, led to an Arg272Gln and to an Arg276Trp amino acid substitution, according to the sequence of the RAR alpha protein. Both patients had complete clinical and hematologic remission after treatment with As2O3. Interpretation and Conclusions. LED missense mutations appear to be a significant mechanism of acquired ATRA-resistance in vivo, closely related to clinical APL relapse. The two cases reported here provide the first in vivo evidence of Apt, relapsed patients, who have become ATRA-resistant for molecular reasons, being sensitive to arsenic trioxide

Idelalisib impairs T-cell-mediated immunity in chronic lymphocytic leukemia

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Lenalidomide interferes with tumor-promoting properties of nurse-like cells in chronic lymphocytic leukemia

Lenalidomide is an immunomodulatory agent clinically active in chronic lymphocytic leukemia patients. The specific mechanism of action is still undefined, but includes modulation of the microenvironment. In chronic lymphocytic leukemia patients, nurse-like cells differentiate from CD14(+) mononuclear cells and protect chronic lymphocytic leukemia cells from apoptosis. Nurse-like cells resemble M2 macrophages with potent immunosuppressive functions. Here, we examined the effect of lenalidomide on the monocyte/macrophage population in chronic lymphocytic leukemia patients. We found that lenalidomide induces high actin polymerization on CD14(+) monocytes through activation of small GTPases, RhoA, Rac1 and Rap1 that correlated with increased adhesion and impaired monocyte migration in response to CCL2, CCL3 and CXCL12. We observed that lenalidomide increases the number of nurse-like cells that lost the ability to nurture chronic lymphocytic leukemia cells, acquired properties of phagocytosis and promoted T-cell proliferation. Gene expression signature, induced by lenalidomide in nurse-like cells, indicated a reduction of pivotal pro-survival signals for chronic lymphocytic leukemia, such as CCL2, IGF1, CXCL12, HGF1, and supported a modulation towards M1 phenotype with high IL2 and low IL10, IL8 and CD163. Our data provide new insights into the mechanism of action of lenalidomide that mediates a pro-inflammatory switch of nurse-like cells affecting the protective microenvironment generated by chronic lymphocytic leukemia into tissues

Switching From Glargine to Degludec: The Effect on Metabolic Control and Safety During 1-Year of Real Clinical Practice in Children and Adolescents With Type 1 Diabetes

Background/Objective: Insulin degludec (IDeg) is an ultra-long-acting analog with less daily variability compared to other basal insulins. In this retrospective study we examined 1-year efficacy and safety of IDeg in youth with type 1 diabetes (T1D).Subjects/Methods: Thirty-seven patients [11.7 ± 4.22 years; T1D duration 4.97 ± 3.63 years; once-daily glargine (IGlar) by at least 1 year] were switched to once-daily IDeg because of glycosylated hemoglobin (HbA1c) >7.5% and/or reported physical pain at IGlar injection. Changes in HbA1c, 30-day mean fasting plasma glucose (mean FPG), daily insulin dose, and severe hypoglycemia rates were collected at basal insulin switch (T0), 3-months (T1), 6-months (T2), and 12-months (T3) after IDeg was started.Results: In patients with HbA1c >7.5% at T0 we found a decrease in HbA1c values (%) from 8.46 ± 0.53 to 7.89 ± 0.72 at T1 (p = 0.008) and 7.97 ± 0.89 at T2 (p = 0.035). At T3, 38.9% of patients had HbA1c ≤ 7.5%. Mean FPG levels significantly decreased at T2 (p = 0.043). In the overall study population, we documented an increase in IDeg dose (+12.5% at T3; p < 0.001) and a decrease in mealtime insulin dose (−11.6% at T3; p = 0.001) after switch. HbA1c levels were unchanged. No episode of severe hypoglycemia was reported.Conclusions: Our data in children and adolescents with T1D suggest that IDeg dose should be increased by 12% and mealtime insulin doses should be lowered by 11% for patients who previously received IGlar. IDeg might be considered useful and well tolerated and it seems to improve the glycemic control compared to IGlar, mainly in patients with poor glycemic control

Ibrutinib modifies the function of monocyte/macrophage population in chronic lymphocytic leukemia

In lymphoid organs, nurse-like cells (NLCs) show properties of tumor-associated macrophages, playing a crucial role in chronic lymphocytic leukemia (CLL) cell survival. Ibrutinib, a potent inhibitor of Bruton's tyrosine kinase (BTK), is able to counteract pro-survival signals in CLL cells. Since the effects on CLL cells have been studied in the last years, less is known about the influence of ibrutinib on NLCs properties. We sought to determine how ibrutinib modifies NLCs functions focusing on the balance between immunosuppressive and inflammatory features. Our data show that ibrutinib targets BTK expressed by NLCs modifying their phenotype and function. Treatment with ibrutinib reduces the phagocytic ability and increases the immunosuppressive profile of NLCs exacerbating the expression of M2 markers. Accordingly, ibrutinib hampers LPS-mediated signaling, decreasing STAT1 phosphorylation, while allows IL-4-mediated STAT6 phosphorylation. In addition, NLCs treated with ibrutinib are able to protect CLL cells from drug-induced apoptosis partially through the secretion of IL-10. Results from patient samples obtained prior and after 1 month of treatment with ibrutinib show an accentuation of CD206, CD11b and Tie2 in the monocytic population in the peripheral blood. Our study provides new insights into the immunomodulatory action of ibrutinib on monocyte/macrophage population in CLL

All-trans retinoic acid (ATRA) in non-promyelocytic acute myeloid leukemia (AML): results of combination of ATRA with low-dose Ara-C in three elderly patients with NPM1-mutated AML unfit for intensive chemotherapy and review of the literature

Based upon the clinical behavior of three patients, we suggest that the combination of low-dose Ara-C and all-trans retinoic acid may potentially be effective in some elderly patients, unfit for intensive chemotherapy, affected with NPM1-mutated acute myeloid leukemia without FLT3 mutations, warranting perspective clinical studies in these selected patients

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

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

The Silent Epidemic of Diabetic Ketoacidosis at Diagnosis of Type 1 Diabetes in Children and Adolescents in Italy During the COVID-19 Pandemic in 2020

To compare the frequency of diabetic ketoacidosis (DKA) at diagnosis of type 1 diabetes in Italy during the COVID-19 pandemic in 2020 with the frequency of DKA during 2017-2019

The Changing Landscape of Neonatal Diabetes Mellitus in Italy Between 2003 and 2022

Context In the last decade the Sanger method of DNA sequencing has been replaced by next-generation sequencing (NGS). NGS is valuable in conditions characterized by high genetic heterogeneity such as neonatal diabetes mellitus (NDM).Objective To compare results of genetic analysis of patients with NDM and congenital severe insulin resistance (c.SIR) identified in Italy in 2003-2012 (Sanger) vs 2013-2022 (NGS).Methods We reviewed clinical and genetic records of 104 cases with diabetes onset before 6 months of age (NDM + c.SIR) of the Italian dataset.Results Fifty-five patients (50 NDM + 5 c.SIR) were identified during 2003-2012 and 49 (46 NDM + 3 c.SIR) in 2013-2022. Twenty-year incidence was 1:103 340 (NDM) and 1:1 240 082 (c.SIR) live births. Frequent NDM/c.SIR genetic defects (KCNJ11, INS, ABCC8, 6q24, INSR) were detected in 41 and 34 probands during 2003-2012 and 2013-2022, respectively. We identified a pathogenic variant in rare genes in a single proband (GATA4) (1/42 or 2.4%) during 2003-2012 and in 8 infants (RFX6, PDX1, GATA6, HNF1B, FOXP3, IL2RA, LRBA, BSCL2) during 2013-2022 (8/42 or 19%, P = .034 vs 2003-2012). Notably, among rare genes 5 were recessive. Swift and accurate genetic diagnosis led to appropriate treatment: patients with autoimmune NDM (FOXP3, IL2RA, LRBA) were subjected to bone marrow transplant; patients with pancreas agenesis/hypoplasia (RFX6, PDX1) were supplemented with pancreatic enzymes, and the individual with lipodystrophy caused by BSCL2 was started on metreleptin.Conclusion NGS substantially improved diagnosis and precision therapy of monogenic forms of neonatal diabetes and c.SIR in Italy

Diabetic ketoacidosis at the onset of disease during a national awareness campaign: a 2-year observational study in children aged 0-18 years

After a previous survey on the incidence of diabetic ketoacidosis (DKA) at onset of type 1 diabetes in children in 2013-2014 in Italy, we aimed to verify a possible decline in the incidence of DKA at onset during a national prevention campaign