Whole-Genome Sequencing and Acute Promyelocytic Leukemia

Management of acute promyelocytic leukemia: updated recommendations from an expert panel of the European LeukemiaNet

Abstract Since the comprehensive recommendations for the management of acute promyelocytic leukemia (APL) reported in 2009, several studies have provided important insights, particularly regarding the role of arsenic trioxide (ATO) in frontline therapy. Ten years later, a European LeukemiaNet expert panel has reviewed the recent advances in the management of APL in both frontline and relapse settings in order to develop updated evidence- and expert opinion–based recommendations on the management of this disease. Together with providing current indications on genetic diagnosis, modern risk-adapted frontline therapy, and salvage treatment, the review contains specific recommendations for the …

Analysis of t(15;17) chromosomal breakpoint sequences in therapy-related versus de novo acute promyelocytic leukemia: Association of DNA breaks with specific DNA motifs at PML and RARA loci

We compared genomic breakpoints at the PML and RARA loci in 23 patients with therapy-related acute promyelocytic leukemia (t-APL) and 25 de novo APL cases.Eighteen of 23 t-APL cases received the topoisomerase II poison mitoxantrone for their primary disorder. DNA breaks were clustered in a previously reported 8 bp "hot spot" region of PML corresponding to a preferred site of mitoxantrone-induced DNA topoisomerase II-mediated cleavage in 39% of t-APL occurring in patients exposed to this agent and in none of the cases arising de novo (P = 0.007). As to RARA breakpoints, clustering in a 3' region of intron 2 (region B) was found in 65% of t-APL and 28% of de novo APL patients, respectively. S…

Ratify (Alliance 10603): Prognostic Impact of FLT3 tyrosine Kinase Domain (TKD) and NPM1 Mutation Status in Patients with Newly Diagnosed Acute Myeloid Leukemia (AML) Treated with Midostaurin or Placebo Plus Standard Chemotherapy

Abstract Introduction: Mutations localized in the tyrosine kinase domain activation loop of FLT3 (FLT3-TKD), representing point mutations in codon D835/I836 and rarely deletions of codon I836, induce constitutive tyrosine phosphorylation and activation of the receptor tyrosine kinase similarly to FLT3 internal tandem duplication (ITD) mutations. However, the prognostic role of FLT3-TKD in AML, particularly in the presence of NPM1 mutations, is not well established. The phase 3 RATIFY trial [NCT00651261; Stone et al. N Engl J Med. 2017] showed that in combination with standard chemotherapy, midostaurin (PKC412) improved survival outcomes across all 3 FLT3 stratification subgroups (ITD high a…

Slit-Robo Pathway Is Clinically Relevant and May Represent a Potential Target in Acute Promyelocytic Leukemia

Abstract Background: The Slit-Robo pathway has been shown to participate in the pathogenesis of several malignant diseases in addition to its physiologic role during the development of the central nervous system (CNS). However, the relevance of the Slit-Robo pathway in acute promyelocytic leukemia (APL) is presently unknown. We investigated the status of the Slit-Robo pathway in APL following the recent demonstration by Amodeo et al (CellRep. 2017) that the PML protein induces neural stem/progenitor cells migration by inhibiting the SLIT2 gene, which was associated with an increased presence of H3K27me3 in the SLIT2 promotor region. Moreover, sensitivity towards the PML-targeting drug arsen…

Metformintreatment Overcomes ATRA-Resistance in Acute Promyelocytic Leukemia and Increases FOXO3A Expression

Abstract Introduction: FOXO3A is a transcription factor shown to be involved in all-trans retinoic acid (ATRA)-induced granulocytic differentiation and apoptosis in acute promyelocytic leukemia (APL). Its biological activity may be significantly enhanced upon metformin, raising the possibility that ATRA and Metformin may act synergistically; which could be useful to overcome ATRA resistance. Despite progress in APL treatment, approximately 10-15% of patients will relapse after treatment with ATRA and anthracyclines and frequently present with ATRA resistance. Relapsed patients respond well to arsenic trioxide (ATO) treatment, but the cost of ATO is a significant barrier in many countries. A…

Improved Outcome with ATRA-Arsenic Trioxide Compared to ATRA-Chemotherapy in Non-High Risk Acute Promyelocytic Leukemia - Updated Results of the Italian-German APL0406 Trial on the Extended Final Series

Abstract Background: We recently showed that the combination of ATRA and arsenic trioxide (ATO) is at least not inferior and possibly superior to standard ATRA and chemotherapy (CHT) in the front-line management of low/intermediate risk APL (Italian-German APL 0406 trial; Lo-Coco et al., NEJM 2013). We report herein on the extended and final series of 276 patients (162 were in the previous report) with the last case being enrolled into the study in January 2013. Methods: The APL0406 study was a prospective, open-label, randomized intergroup trial conducted by the Italian GIMEMA and the German SAL and AMLSG study groups. Eligible patients were adults aged 18-<71 years with newly diagnosed…

Midostaurin in patients with acute myeloid leukemia and FLT3-TKD mutations: a subanalysis from the RATIFY trial

Abstract The results from the RATIFY trial (ClinicalTrials.gov: NCT00651261; CALGB 10603) showed that midostaurin combined with standard chemotherapy significantly improved outcomes in patients with FMS-like tyrosine kinase 3 (FLT3)–mutated acute myeloid leukemia (AML), compared with placebo. In this post hoc subgroup analysis from the trial, we evaluated the impact of midostaurin in 163 patients with FLT3-tyrosine kinase domain (TKD) mutations. At a median follow-up of 60.7 months (95% CI, 55.0-70.8), the 5-year event-free survival (EFS) rate was significantly higher in patients treated with midostaurin than in those treated with placebo (45.2% vs 30.1%; P = .044). A trend toward improved …

The experience of the International Consortium on Acute Promyelocytic Leukemia in monitoring minimal residual disease in acute promyelocytic leukaemia

Arsenic trioxide-based therapy of relapsed acute promyelocytic leukemia: registry results from the European LeukemiaNet

In 2008, a European registry of relapsed acute promyelocytic leukemia was established by the European LeukemiaNet. Outcome data were available for 155 patients treated with arsenic trioxide in first relapse. In hematological relapse (n=104), 91% of the patients entered complete hematological remission (CR), 7% had induction death and 2% resistance, 27% developed differentiation syndrome and 39% leukocytosis, whereas no death or side effects occurred in patients treated in molecular relapse (n=40). The rate of molecular (m)CR was 74% in hematological and 62% in molecular relapse (P=0.3). All patients with extramedullary relapse (n=11) entered clinical and mCR. After 3.2 years median follow-u…

Tamibarotene in patients with acute promyelocytic leukaemia relapsing after treatment with all-trans retinoic acid and arsenic trioxide

Treatment of acute promyelocytic leukaemia (APL) with arsenic trioxide (ATO) and all-trans retinoic acid (ATRA) is highly effective first-line therapy, although approximately 5-10% of patients relapse. Tamibarotene is a synthetic retinoid with activity in APL patients who relapse after chemotherapy and ATRA, but has not been studied in relapse after treatment with ATO and ATRA. We report on a phase II study of tamibarotene in adult patients with relapsed or refractory APL after treatment with ATRA and ATO (n = 14). Participants were treated with tamibarotene (6 mg/m(2) /d) during induction and for up to six cycles of consolidation. The overall response rate was 64% (n = 9), the rate of comp…

Biology and management of therapy-related acute promyelocytic leukemia.

Therapy-related acute promyelocytic leukemia (t-APL) has been increasingly reported after exposure to cytotoxic and/or immunosuppressive agents given for prior malignancies or autoimmune diseases. t-APL represents both a model for better understanding human leukemogenesis and an interesting therapeutic subset which requires specific adaptations for optimal management.We discuss here potential risk factors for t-APL development and the main biologic and clinical characteristics of t-APL as compared to de-novo APL.In addition, we review therapeutic results obtained in patients with t-APL receiving conventional retinoic acid and chemotherapy and discuss new treatment opportunities with minimal…

Diagnosis and management of AML in adults: 2017 ELN recommendations from an international expert panel

Abstract The first edition of the European LeukemiaNet (ELN) recommendations for diagnosis and management of acute myeloid leukemia (AML) in adults, published in 2010, has found broad acceptance by physicians and investigators caring for patients with AML. Recent advances, for example, in the discovery of the genomic landscape of the disease, in the development of assays for genetic testing and for detecting minimal residual disease (MRD), as well as in the development of novel antileukemic agents, prompted an international panel to provide updated evidence- and expert opinion-based recommendations. The recommendations include a revised version of the ELN genetic categories, a proposal for …