Acute promyelocytic leukemia (APL) is highly curable with the combination of all-trans retinoic acid (ATRA) and anthracycline-based chemotherapy (CT), but very long-term results of this treatment, ...when CT should be added to ATRA and the role of maintenance treatment, remain uncertain. In our APL93 trial that included 576 newly diagnosed APL patients, with a median follow-up of 10 years, 10-year survival was 77%. Maintenance treatment significantly reduced 10-year cumulative incidence of relapses, from 43.2% to 33%, 23.4%, and 13.4% with no maintenance, maintenance using intermittent ATRA, continuous 6 mercaptopurine plus methotrexate, and both treatments, respectively (P < .001). Maintenance particularly benefited patients with white blood cell (WBC) count higher than 5 × 109/L (5000/μL). Early addition of CT to ATRA significantly improved 10-year event-free survival (EFS), but without significant effect on overall survival (OS). The 10-year cumulative incidence of deaths in complete response (CR), resulting mainly from myelosuppression, was 5.7%, 15.4%, and 21.7% in patients younger than 55, 55 to 65, and older than 65 years, respectively, supporting the need for less myelosuppressive treatments, particularly for consolidation therapy. This study is registered at http://clinicaltrials.gov as NCT00599937.
The independent prognostic impact of specific dysplastic features in acute myeloid leukemia (AML) remains controversial and may vary between genomic subtypes. We apply a machine learning framework to ...dissect the relative contribution of centrally reviewed dysplastic features and oncogenetics in 190 patients with de novo AML treated in ALFA clinical trials. One hundred and thirty-five (71%) patients achieved complete response after the first induction course (CR). Dysgranulopoiesis, dyserythropoiesis and dysmegakaryopoiesis were assessable in 84%, 83% and 63% patients, respectively. Multi-lineage dysplasia was present in 27% of assessable patients. Micromegakaryocytes (q = 0.01), hypolobulated megakaryocytes (q = 0.08) and hyposegmented granulocytes (q = 0.08) were associated with higher ELN-2017 risk. Using a supervised learning algorithm, the relative importance of morphological variables (34%) for the prediction of CR was higher than demographic (5%), clinical (2%), cytogenetic (25%), molecular (29%), and treatment (5%) variables. Though dysplasias had limited predictive impact on survival, a multivariate logistic regression identified the presence of hypolobulated megakaryocytes (p = 0.014) and micromegakaryocytes (p = 0.035) as predicting lower CR rates, independently of monosomy 7 (p = 0.013), TP53 (p = 0.004), and NPM1 mutations (p = 0.025). Assessment of these specific dysmegakarypoiesis traits, for which we identify a transcriptomic signature, may thus guide treatment allocation in AML.
•LIM kinase 1 and 2 are expressed in FLT3-ITD mutated AML cell lines.•The LIMK1/2 inhibitor CEL_Amide has antiproliferative effects in those cells.•CEL_Amide synergizes with FLT3-ITD inhibitors in ...vitro and in vivo.•Dephosphorylation of cofilin constitutes a potential biomarker for LIMK1/2 action.
Patients with FLT3-ITD mutated (FLT3-ITD+) Acute Myeloid Leukemia (AML), have frequently relapsed or refractory disease and FLT3-ITD+ inhibitors have limited efficacy. Rho kinases (ROCK) are constitutively activated by FLT3-ITD+ in AML via PI3 kinase and Rho GTPase. Upon activation by ROCK, LIM kinases (LIMK) inactivate cofilin by phosphorylation which affects cytoskeleton dynamics, cell growth and apoptosis. LIMK inhibition leads to cofilin activation via dephosphorylation and activated cofilin localizes to mitochondria inducing apoptosis. Thus, we investigated the therapeutic potential of the LIMK1/2 inhibitor CEL_Amide (LIMKi) in FLT3-ITD+ AML. Expression of LIMK1/2 in FLT3-ITD+ cell lines MOLM-13 and MV-4-11 cells could be detected by RT-qPCR and at the protein level. IC50 after LIMKi monotherapy was 440 nM in MOLM-13 cells and 420 nM in MV4-11 cells. Treatment with LIMKi decreased LIMK1 protein levels and repression of inactivating phosphorylation of cofilin in FLT3-ITD+ cells. Combination experiments with LIMKi and FLT3 inhibitors including midostaurin, crenolanib and gilteritinib were synergistic for treatment of MOLM-13 cells while combinations with quizartinib were additive. Combinations of LIMKi and the hypomethylating agent azacitidine or the ROCK inhibitor fasudil were additive. In NOD-SCID mice engrafted with MOLM13-LUC cells, the FLT3 inhibitor midostaurin and LIMKi delayed MOLM13-LUC engraftment as detected by in vivo bioluminescence imaging and the LIMKi and midostaurin combination prolonged significantly survival of leukemic mice. LIMK1/2 inhibition by the small molecule CEL_Amide seems to have promising activity in combination with FLT3 inhibitors in vitro as well as in vivo and may constitute a novel treatment strategy for FLT3-ITD+ AML.
Introduction: The dual-specificity protein kinase, monopolar spindle 1 (Mps1) is one the main kinases of the spindle assembly checkpoint (SAC) critical for accurate segregation of sister chromatids ...during mitosis. A hallmark of cancer cells is chromosomal instability caused by deregulated cell cycle checkpoints and SAC dysfunction. Mps1 is known to be overexpressed in several solid tumors including triple negative breast cancer. Thus, Mps1 seems to be a promising target and small molecules targeting Mps1 entered clinical trials in solid tumors. ALL originates from malignant transformation of B-and T-lineage lymphoid precursors with a variety of genetic aberrations including chromosome translocations, mutations, and aneuploidies in genes responsible for cell cycle regulation and lymphoid cell development. While outcome is excellent for pediatric patients and younger adults, relapsed and refractory disease still remain a clinical challenge for elder patients. Here, we demonstrate for the first time preclinical efficacy of the small molecule Mps1 inhibitor (Mps1i) S81694 in T- and B- ALL cells including BCR-ABL1+-driven B-ALL.
Materials and Methods: Expression of Mps1 was determined by RT-qPCR and WB in JURKAT, RS4-11 and BCR-ABL1+ cells (BV-173 and TOM-1). A small molecule Mps1i (S81694) was tested alone (0 to 1000nM) or in combination with imatinib, dasatinib, nilotinib and ponatinib in BCR-ABL1+ ALL cell lines. Cell viability and IC50 was assessed by MTS assays after exposure to Mps1i for 72h. In combination experiments, compounds were added simultaneously and relative cell numbers were determined at 72h with MTS assays and combination index (CI) values were calculated according to the Bliss model. Induction of apoptosis was evaluated by annexin-V exposure and PI incorporation at 72h with increasing doses of Mps1i. Cell-cycle distribution was determined by cytofluorometric analysis detecting nuclear propidium iodide (PI) intercalation at 48h. Phosphorylation of Mps1 was detected in synchronized (by nocodazole and MG-132) cells by immunofluorescence using an anti phospho-Mps1 antibody detecting Thr33/Ser37 residues. Time-lapse microscopy was used in cell lines in presence or absence of S81694 to determine mitosis duration. Bone marrow (BM) nucleated patient cells were obtained after informed consent and incubated in methylcellulose with cytokines with or without Mps1i for 2 weeks to determine colony growth.
Results: Expression of Mps1 could be detected by RT-qPCR and at the protein level by WB in all cell lines (Figure 1A and B ). IC50 after Mps1i exposure alone was 126nM in JURKAT cells, 51nM in RS4-11 cells, 75nM in BV-173 cells and 83nM in TOM-1. Significant apoptosis as detected by phosphatidylserine exposure and PI incorporation in all cell lines with BCR-ABL1+ cell lines BV-173 and TOM-1 cells being the most sensitive (80% and 60% apoptotic cells respectively)(Figure 1C). Upon Mps1i exposure we observed targeted inhibition of Mps1 phosphorylation at Thr33/Ser37 residues indicating the specific on target effect of S81694 by inhibiting Mps1 autophosphorylation (Figure 1D and E). Cell cycle profile was generally lost after treatment with S81694 in all cell lines indicating aberrant 2n/4n distribution due to SAC abrogation (Figure 1F). Furthermore, we demonstrated that S81694 exposure accelerated significantly mitosis in BV-173 cell line from 36 minutes to 19 minutes indicating effective inhibition of SAC function (Figure 1G). Interestingly, S81694 induced significant apoptosis (70%) in the imatinib resistant BV173 cell line bearing the E255K-BCR-ABL1-mutation. Combination of S81694 with TKI imatinib, dasatinib and nilotinib (but not ponatinib) was strongly synergistic in BCR-ABL1+ cells (Figure 1H). Finally, we observed inhibition of colony formation in a patient with BCR-ABL1+ B-ALL after exposure to 100nM and 250nM S81694 (reduction of 85% and 100% respectively)(Figure 1I).
Conclusion: Mps1i S81694 yields significant preclinical activity in T-and B-cell ALL including BCR-ABL1+ models. Interestingly S81694 was efficacious in a TKI resistant cell line.
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Kaci:Institut de Recherches Internationales Servier (IRIS): Employment. Garrido:Institut de Recherches Internationales Servier (IRIS): Employment. Burbridge:Institut de Recherches Internationales Servier (IRIS): Employment. Dombret:AGIOS: Honoraria; CELGENE: Consultancy, Honoraria; Institut de Recherches Internationales Servier (IRIS): Research Funding. Braun:Institut de Recherches Internationales Servier (IRIS): Research Funding.
Acute myeloid leukemia in the elderly Dombret, Hervé; Raffoux, Emmanuel; Gardin, Claude
Seminars in oncology,
08/2008, Volume:
35, Issue:
4
Journal Article
Peer reviewed
The incidence of acute myeloid leukemia (AML) is increasing with age. As the results associated with standard intensive chemotherapy remain particularly disappointing in older patients, they ...represent an ideal target population for clinical and therapeutic investigations. Current attempts are to better define those who may draw a significant benefit from intensive chemotherapy, in order to test new less intensive approaches in the remaining patients. Hopefully, a lot of promising alternative therapies are emerging, including hypomethylating agents, histone deacetylase inhibitors, monoclonal antibodies, or chemotherapeutic agents such as cloretazine or clofarabine. Reduced-intensity conditioning stem cell transplantation or other various immunological approaches represent another way of investigation.
Introduction: LIM kinases 1 and 2 (LIMK1/2) are downstream effectors at the crossroads of different signaling pathways implicated in the dynamics of the cytoskeleton via phosphorylation of cofilin ...family proteins, degradation of the matrix by phosphorylating MT1-MMP and control of the activity of Aurora kinase A. Recently, the oncogenic role of Rho kinases (ROCK) was identified to be constitutively activated by BCR-ABL1, FLT3-ITD and KIT in hematologic malignancies via PI3 kinase and Rho GTPase mediated phosphorylation. Upon activation, ROCK phosphorylates LIMK1/2 leading to inactivation of cofilin by its phosphorylation and polymerization of actin and microtubules and possibly to other biological effects mediated by LIMK1/2, not yet fully understood. Here, we demonstrate synergy of a LIMK1/2 inhibitor with BCR-ABL1 tyrosine kinase inhibitors (TKI) in vitro and in vivo in different models for BCR-ABL1 driven ALL.
Materials and Methods: Expression of LIMK1/2 was determined by RT-qPCR and WB in cell lines. Phosphorylation of cofilin was detected by WB. A small molecule inhibitor of LIMK1/2 was tested alone and in combination with imatinib, dasatinib, nilotinib and ponatinib in BCR-ABL1 positive ALL cell lines TOM-1 and BV-173. Cell viability and IC50 was assessed by MTS assays after exposure to LIMK1/2 inhibitor for 72h. In combination experiments, compounds were added simultaneously and relative cell numbers were determined at 72h with MTS assays and combination index (CI) values were calculated according to the Chou-Talalay model. Cell-cycle distribution was determined by cytofluorometric analysis detecting nuclear propidium iodide (PI) DNA intercalation. Induction of apoptosis was evaluated by annexin-V exposure and PI incorporation at 72h with increasing doses of LIMK1/2 inhibitor. Peripheral blood (PB) nucleated cells from apharesis products of healthy donors obtained after informed consent according to Helsinki declaration were incubated with or without LIMK1/2 inhibitor for 72h, and then enriched for CD34+ cells by immuno-magnetic selection and seeded in triplicate in methylcellulose FCS and cytokines. In vivo experiments were performed in C57Bl/6 mice injected with BCR-ABL-induced B-ALL cells. These were obtained by transduction of CDKN2A-deficient B-cell progenitors with a retrovirus coding for BCR-ABL1 (P185) and GFP, followed by transplantation in sub-lethally-irradiated recipient C57Bl/6 mice. Mice were treated either with LIMK1/2 inhibitor, nilotinib or the combination of both and compared to untreated control mice.
Results: Expression of the two isoforms LIMK1 and LIMK2 in TOM-1 and BV-173 cells could be detected by RT-qPCR and at the protein level by WB. IC50 after LIMK1/2 inhibitor exposure alone was 580nM in TOM-1 cells and 1000nM in BV-173 cells. All combination experiments with the LIMK1/2 inhibitor and imatinib, dasatinib, nilotinib and ponatinib yielded synergistic CI for treatment of both TOM-1 and BV-173 cell lines. Cell cycle arrest in the G1/S transition was detected and LIMK1/2 inhibition induced dose dependent apoptosis in TOM-1 and BV-173 cells up to 40% at doses <1000nM. Upon treatment with the LIMK1/2 inhibitor, decrease of LIMK1 protein expression could be detected by WB, while LIMK2 expression was left unaffected. In both cell lines, LIMK1/2 inhibitor exposure lead to activating downstream dephosphorylation of cofilin as expected. No significant toxicity of increasing doses of LIMK1/2 inhibitor after exposure of CD34+ cells from healthy donors could be detected. To test the in vivo activity of LIMK1/2 inhibition, C57Bl/6 mice were transplanted with CDKN2Ako/BCR-ABL1+ B-ALL cells. Leukemic mice were treated with LIMK1/2 inhibitor alone, nilotinib or combination of LIMK1/2 inhibitor and nilotinib compared to untreated mice. The combination of nilotinib and LIMK1/2 inhibitor significantly delayed the appearance of leukemic cells in PB as detected by GFP+ cells once weekly or at death if possible with mice considered having leukemia if >1% GFP+ cells were detected in PB. Furthermore, nilotinib+LIMK1/2 inhibitor prolonged significantly the survival of mice compared to either nilotinib (p=0.0006) or LIMK1/2 inhibitor alone and untreated mice (p<0.0001) (Figure 1).
Conclusion: Combination of LIMK1/2 inhibitor with BCR-ABL targeting TKI is synergistic and has significant anti-leukemic activity in BCR-ABL1+ ALL in vitro and in vivo models.
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Braun:CELLIPSE: Research Funding. Prudent:CELLIPSE: Employment. Paublant:CELLIPSE: Employment. Baruchel:Jazz Pharmaceuticals: Consultancy, Honoraria, Other: Travel, accommodations or expenses; Shire: Research Funding; Servier: Consultancy; Amgen: Consultancy; Novartis: Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy; Roche: Consultancy. Dombret:CELLIPSE: Research Funding.
Background: High-risk (HR) AML including secondary AML (sAML) or therapy-related (tAML) are associated with significantly lower complete remission (CR) rates and poor outcome, after upfront “3+7” and ...post-remission chemotherapy. No standard intensive treatment approach for relapsed/refractory AML is well established, even more so, in older patients, but “bridging” such patients in CR to allogeneic stem-cell transplantation (HSCT), whenever feasible, remain the only curative strategy, as in younger patients. Addition of cladribine, a purine analog, to cytarabine is an available option. Significant clinical activity of CLAG (-M) regimens is now well established, with a response rate (RR) of 60% in relapsed/refractory AML or AML patients who failed hypomethylating agents. A prospective frontline study of an intensified CLAG-M regimen has recently confirmed its association to a high response rate, that may particularly benefit HR-AML patients, as a bridge to HSCT. As other reports in the literature remain sparse, we report here our current experience with CLAG-M in relapsed/refractory and sAML patients. Methods: From January 2015 to July 2018, 20 consecutive patients with HR-AML, were treated in our center, with one course of CLAG-M (cladribine 5 mg/m2 /day (days 2-6), cytarabine 2g/m2/day (days 2-6) and reduced to 1g/m2/day for patients 65y+, filgrastim 300mcg/daily (days 1-6), and mitoxantrone 10mg/m2/day (days 2-4)). If eligible for HSCT, a second CLAG course was to be administered to patients in CR. Extended myeloid mutation analysis was performed, using a 37-gene NGS panel. Such patients were classified according to Lindsley et al.,Blood 2015. Results: Median age was 63.5 years (33-79) with a 3:1 M/F ratio. Four sAML patients and 4 tAML patients were treated upfront (5 CR, 1 early death (ED) and 2 treatment failures). ELN cytogenetics was adverse (n=5), intermediate (n=1) or failed (n=4). Twelve patients were all treated after frontline 7+3 and intensive consolidation courses (n=10) or azacytidine (n=2). Three patients were refractory to prior intensive chemotherapy or AZA and 9 were in first or subsequent relapse, at time of CLAG-M administration. Median time from first treatment for MDS/AML to CLAG-M onset was 17 mos (3-29). Initial/relapse ELN cytogenetics was adverse (n=5), intermediate (n=5) and failed (n=2). Of these 12 patients, 7 obtained a response (6 CR, one CRi), 3 failed to obtain a response and 2 early died from sepsis. Seventeen patients could be classified, according to Lindsley et al. The 3 patients with missing NGS data, all had adverse ELN cytogenetics (inv3q/MECOM1, MLLr by FISH analysis or monosomy 7, associated with an IDH2 mutation). After one course, 5/7 patients, classified as secondary AML, obtained a CR, including one CRi, 3/4 patients classified as pan AML obtained a CR, while only 2/6 patients with mutated TP53 alleles obtained a CR (3 failed to respond). Overall, 12 of the 20 patients obtained a complete response (11 CR and 1 CRi), despite adverse genetical characteristics and 12 of them being administered CLAG-M, during the late evolution of their disease. Three patients early died due to undocumented pneumonitis (n=2) or bacterial sepsis (n=1). Otherwise, observed treatment toxicities were mild, with no unusual infections seen after CLAG-M. Median duration of neutropenia (<0.5 G/l) and thrombocytopenia (<100 G/l) was 28 (12-47) and 30 (23-40) days, respectively. Seven patients in CR received a second CLAG course before HSCT, when 3 patients, aged more than 70 years, only less intensive courses. One CR patient did not received consolidation due to severe sepsis, as also did the only patient with CRi due to persisting cytopenias. Both patients underwent HSCT. Fifteen patients were deemed eligible at entry for HSCT, based on age and performance status. Of those, 8 achieved a CR/CRi and all of them proceeded to HSCT. Four such patients are currently alive (2 mo, 2.6 y, 3y, 3.4y), 2 patients died from early relapse (4 and 6 mos) and 2 patients from HSCT toxicity. Conclusions: In this real-life small study of HR-AML patients, predominantly older than 60 years of age, CLAG-M was also used at first or subsequent relapse post-intensive therapy. Despite very unfavorable characteristics, 60 % of them obtained a complete response and 50% of those initially eligible were effectively “bridged ”to HSCT, without unusually deleterious outcomes observed in this small cohort.
Peffault De Latour:Amgen Inc.: Research Funding; Pfizer Inc.: Consultancy, Honoraria, Research Funding; Alexion Pharmaceuticals, Inc.: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding. Braun:CELLIPSE: Research Funding.
Higher-risk MDS with del5q carry a poor prognosis. In this phase 2 trial, 47 patients with higher-risk MDS received lenalidomide 10 mg/day. International Prognostic Scoring System was high in 60%, ...intermediate-2 risk in 40%. del 5q was isolated, with one additional and more than one additional abnormality in 19%, 23%, and 58% patients, respectively. Thirteen (27%) patients achieved hematologic response, including 7 hematologic complete remission (CR) (with complete 4 or partial 3 cytogenetic response), 2 marrow CR and 4 hematologic improvement erythroid, and 12 became red blood cell (RBC) transfusion independent, for a median duration of 6.5 months. Median CR duration was 11.5 months. Six of 9 (67%) patients with isolated del 5q achieved CR, versus 1 of 11 and none of 27 patients with one or more than one additional abnormality, respectively (P < .001). Seven of 20 (35%) with initial platelets more than 100 000/mm3 obtained CR, compared with none of the 27 with lower platelet counts less than 100 000/mm3 (P = .001). Our data support a potential role of lenalidomide in higher-risk MDS with isolated del 5q. This trial was registered at www.clinicaltrials.gov as NCT00424229.
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