Search

Ph+ (BCR::ABL+) B-ALL was considered to be high risk, but recent advances in BCR::ABL-targeting TKIs has shown improved outcomes in combination with backbone chemotherapy. Nevertheless, new treatment strategies are needed, including approaches without chemotherapy for elderly patients. LIMK1/2 acts downstream from various signaling pathways, which modifies cytoskeleton dynamics via phosphorylation of cofilin. Upstream of LIMK1/2, ROCK is constitutively activated by BCR::ABL, and upon activation, ROCK leads to the phosphorylation of LIMK1/2, resulting in the inactivation of cofilin by its phosphorylation and subsequently abrogating its apoptosis-promoting activity. Here, we demonstrate the anti-leukemic effects of a novel LIMK1/2 inhibitor (LIMKi) CEL_Amide in vitro and in vivo for BCR::ABL-driven B-ALL. The IC50 value of CEL_Amide was ≤1000 nM in BCR::ABL+ TOM-1 and BV-173 cells and induced dose-dependent apoptosis and cell cycle arrest in these cell lines. LIMK1/2 were expressed in BCR::ABL+ cell lines and patient cells and LIMKi treatment decreased LIMK1 protein expression, whereas LIMK2 expression was unaffected. As expected, CEL_Amide exposure caused specific activating downstream dephosphorylation of cofilin in cell lines and primary cells. Combination experiments with CEL_Amide and BCR::ABL TKIs imatinib, dasatinib, nilotinib, and ponatinib were synergistic for the treatment of both TOM-1 and BV-173 cells. CDKN2Ako/BCR::ABL1+ B-ALL cells were transplanted in mice, which were treated with combinations of CEL_Amide and nilotinib or ponatinib, which significantly prolonged their survival. Altogether, the LIMKi CEL_Amide yields activity in Ph+ ALL models when combined with BCR::ABL-targeting TKIs, showing promising synergy that warrants further investigation. [ABSTRACT FROM AUTHOR]

The bromodomain and extra-C-terminal domain (BET) protein family is a class of epigenetic readers that recognize acetyl-lysine residues of histones, and their targeting with small molecules is a novel therapeutic approach [[1]]. Cell cycle and apoptosis induction were evaluated in a subset of cell lines, including two resistant models (NALM1, K562) after 48-h treatments with 500 nM OTX015 (Figure 1(A)). Similarly, OTX015 significantly down-regulated I MTHFD1L i and I BCL2 i in all leukemic cell lines after 4 or 24 h of treatment, in a similar manner as I MYC i , although the effect on I BCL2 i appeared reversible in three nonresistant cell lines (Figure S2). We then evaluated the downstream effects of OTX015 (500 nM) combined with azacitidine (3 µM) or panobinostat (20 nM) in sensitive and resistant OTX015 cell lines. [Extracted from the article]

Azacitidine (AZA) prolonged overall survival (OS) in the AZA-AML-001 trial. However, few subjects were randomized to AZA or intensive chemotherapy (IC). The Medical Research Council (MRC) and the Leukemia Research Foundation (LRF) developed a score for older AML patients receiving IC or non-intensive regimens, whereas the E-ALMA study validated a score for survival and response in elderly patients receiving AZA in daily practice. Both identified three groups with different risk estimates. This analysis evaluates the efficacy of frontline AZA in older AML patients (N = 710) unfit for IC from different national registries (E-ALMA + series) stratified by the MRC/LRF risk score. Median OS of patients categorized as good, standard and poor-risk groups by the MRC/LRF score was 13.4 (95% CI, 10.8-16), 12.4 (95% CI, 9.9-14.8), and 8.1 months (95% CI, 7-9.1), respectively (p = .0001). In conclusion, this is the largest retrospective cohort of older AML patients treated with AZA. [ABSTRACT FROM AUTHOR]

Acute myeloid leukemia (AML) is predominantly a disease of older adults associated with poor long-term outcomes with available therapies. Used as single agents, hypomethylating agents (HMAs) induce only 15 to 25% complete remissions, but current data suggest that median OS observed after HMAs is comparable to that observed after more intensive therapies. Whether long-term cure may be obtained in some patients treated with HMAs is unknown. Combinations of HMAs to novel agents are now extensively investigated and attractive response rates have been reported when combining HMAs to different drug classes. The absence of reliable predictive biomarkers of efficacy of HMAs in AML and the uncertainties regarding their most relevant mechanisms of action hinder the rational design of the combinations to be tested in priority, usually in untreated older AML patients. [ABSTRACT FROM AUTHOR]

Infections are a major complication in patients with acute myeloid leukemia undergoing intensive chemotherapy. They remain a major cause of therapy-associated morbidity and mortality, and represent a frequent cause of treatment withdrawal. An analysis of the medical charts of 459 younger adults included in the multicenter Acute Leukemia French Association (ALFA)-9802 trial showed that 1369 febrile episodes occurred among the 459 registered patients, including fever without identifiable source (23%) and clinically or microbiologically documented infections (77%). Bloodstream infections occurred in 314 episodes, including 129 documented episodes with Gram-positive and 96 with Gram-negative pathogens. Pulmonary infection was diagnosed in 144/1054 documented infectious episodes (14%). Invasive fungal infection was probable or proven in 116 patients. In all, 15 patients died of infection-associated complications, of whom seven died during early induction therapy, one during salvage therapy and seven during consolidation therapy. Better supportive care strategies may improve overall survival in patients undergoing chemotherapy for acute myeloid leukemia. [ABSTRACT FROM AUTHOR]

The article presents a study on leukemic cell priming with granulocyte-macrophage colony-stimulating factor (GM-CSF) which may modulate cell cycle kinetics and susceptible to phase-specific chemotherapeutic agents. In this study, cytogenetics, mutation detection and statistical analysis were used to 259 patients with acute myeloid leukemia (AML). The results show that priming of leukemia cells with GM-CSF may enhance complete remission (CR) rate and event-free survival (EFS).

BET inhibitors (BETi) including OTX015 (MK-8628) and JQ1 demonstrated antileukemic activity including NPM1c AML cells. Nevertheless, the biological consequences of BETi in NPM1c AML were not fully investigated. Even if of better prognosis AML patients with NPM1c may relapse and treatment remains difficult. Differentiation-based therapy by all trans retinoic acid (ATRA) combined with arsenic trioxide (ATO) demonstrated activity in NPM1c AML. We found that BETi, similar to ATO + ATRA, induced differentiation and apoptosis which was TP53 independent in the NPM1c cell line OCI-AML3 and primary cells. Furthermore, BETi induced proteasome-dependent degradation of NPM1c. BETi degraded NPM1c in the cytosol while BRD4 is degraded in the nucleus which suggests that restoration of the NPM1/BRD4 equilibrium in the nucleus of NPM1c cells is essential for the efficacy of BETi. While ATO + ATRA had significant biological activity in NPM1c IMS-M2 cell line, those cells were resistant to BETi. Gene profiling revealed that IMS-M2 cells probably resist to BETi by upregulation of LSC pathways independently of the downregulation of a core BET-responsive transcriptional program. ATO + ATRA downregulated a NPM1c specific HOX gene signature while anti-leukemic effects of BETi appear HOX gene independent. Our preclinical results encourage clinical testing of BETi in NPM1c AML patients. [ABSTRACT FROM AUTHOR]

Several reports of successful empirical treatment of idiopathic hypereosinophilic syndrome with imatinib led to the recent identification of the FIP1L1–PDGFRA fusion gene rearrangement, which characterizes a distinctive group of chronic eosinophilic leukemias. This fusion gene can be detected in eosinophils, neutrophils, mast cells, T cells, B cells and monocytes in FIP1L1–PDGFRA-positive hypereosinophilic patients suggesting a multilineage involvement. Furthermore, the same FIP1L1–PDGFRA rearrangement was identified in patients with hypereosinophilia and atypical mast cell proliferations, raising the question of a disease with two concomitant lines of differentiation. In addition, a recent report noted two cases with the association of FIP1L1–PDGFRA-positive chronic eosinophilic leukemia and T-cell lymphoblastic lymphoma (T-LBL). We report here the only third case of synchronous chronic eosinophilic leukemia and T-LBL, both associated with a FIP1L1–PDGFRA fusion transcript, confirming the occurrence of such disease and suggesting a clonal proliferation with two lines of differentiation probably arising from a primitive multipotent medullary stem cell. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Hemophagocytic syndrome has been defined as the combination of a proliferation of cytologically benign, actively phagocytic macrophages in bone marrow, spleen, or lymph nodes in association with fever, cytopenia, splenomegaly, and hypertriglyceridemia. Hepatic dysfunction is often present but the nature of the hepatic lesions and related manifestations have not been fully characterized. The aim of this study was to ascertain the features of hepatic involvement in hemophagocytic syndrome. METHODS: Thirty patients with hemophagocytic syndrome were retrospectively studied. Inclusion criteria included: 1) bone marrow with hemophagocytic histiocytosis, 2) clinical or biological signs of hepatic involvement, and 3) available liver specimen. RESULTS: The association of fever, jaundice, and hepatomegaly or splenomegaly was present in 50% of the patients. Median value for serum alanine transaminase activity was five times the upper limit of normal values (range, 0.3-125), for serum alkaline phosphatase activity 2.7 upper limit of normal values (range, 0.2-47.7), for total bilirubin 136 µmol/L (range, 4-681 µmol/L), and for factor V 70% (range, 19-145%). Sinusoidal dilatation with hemophagocytic histiocytosis were found in the biopsy specimen in all patients. An underlying condition potentially responsible for altered immune function (lymphoma, leukemia, liver transplantation) was identified in 29 patients. Liver biopsy was diagnostic for the underlying condition in 15 patients (including eight cases with nonspecific bone marrow biopsy findings). High serum bilirubin, elevated serum alkaline phosphatase activity, low factor V level, and lack of treatment for the underlying disease were associated with a poor prognosis. CONCLUSIONS: Hemophagocytic syndrome should be suspected in immunodeficient patients with fever, jaundice, and hepatosplenomegaly. Hepatic lesions are characterized by nonspecific sinusoidal dilatation with hemophagocytic histiocytosis and in 50% of the patients by alterations specific to the underlying condition. Liver biopsy is a useful diagnostic procedure in patients with this clinical presentation. [ABSTRACT FROM AUTHOR]

In spite of the recent improvement in the outcome of acute promyelocytic leukaemia (APL) with treatment combining all trans retinoic acid (ATRA) and chemotherapy (CT), some patients with this disease still have a poor outcome. The prognostic significance of chromosomal abnormalities in addition to t(15;17) in APL is uncertain. We examined the prognostic significance of secondary chromosomal changes in 292 patients included in a European trial who were treated with ATRA and CT. The incidence of chromosomal abnormalities in addition to t(15;17) was 26% and trisomy 8 was the most frequent secondary change (46% of the cases with secondary changes). No significant differences were seen with regard to age, sex, initial white blood cell count, % of circulating blasts, platelet count, fibrinogen level and incidence of microgranular variants between patients with or without additional rearrangements. Outcome was also similar between patients with t(15;17) alone and patients with t(15;17) and other clonal abnormalities for complete remission (92% vs. 93% respectively), event-free survival at 2 years (76·1% vs. 78·1% respectively), relapse at 2 years (16·7% vs. 11·6% respectively) and overall survival at 2 years (79·9% vs. 79·5% respectively). Analysis according to the type of induction treatment (ATRA followed by CT or ATRA plus CT) or the type of maintenance treatment (with ATRA, low-dose CT or both) also failed to show any difference between the two groups. Thus, in a large cohort of APL patients treated with ATRA and CT, additional chromosomal abnormalities had no impact on prognosis. [ABSTRACT FROM AUTHOR]

The article presents information on a study which showed that the outcome of high risk myelodysplastic syndrome (MDS) after azacitidine (AZA) failure. The study the outcome of 74 patients with secondary acute myeloid leukaemia (AML) after AZA treatment failure, collected from two Johns Hopkins University trials and the French AZA compassionate programme.

The article reports that activating somatic mutations in Tyrosine Kinase (TK) genes are frequent events in haematological malignancies. The structural and functional consequences of these mutations were variable in molecular modelling. Group for Research on Adult Acute Lymphoblastic Leukaemia (GRAAL) study included assesment of JAK1, a Janus Kinase (JAK) family member.