Ph Acute Lymphoblastic Leukemia Research Articles

Comparison of Reduced Intensity Conditioning - Allogeneic HCT and Autologous HCT for Elderly Patients with Acute Lymphoblastic Leukemia. an Analysis from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation

BACKGROUND: The outcome of patients with acute lymphoblastic leukemia (ALL) aged above 55 years treated with conventional-dose chemotherapy is poor. Due to the frequent presence of co-morbidities many patients are ineligible for myeloablative allogeneic (allo) hematopoietic cell transplantation (HCT). The role of autologous (auto) HCT and reduced intensity conditioning (RIC)-alloHCT is not well-established. The goal of this study was to analyze results of these transplant options and to identify factors affecting outcome. PATIENTS: Five-hundred and sixty patients with ALL treated in first complete remission (CR1) with RIC-alloHCT (n=418) or autoHSCT (n=142), between 2000-2018, were included in the analysis. Among allogeneic donors, 50% were HLA-matched sibling donors (MSD) and 50% were 8/8 HLA matched unrelated donors (MUD). Median age for RIC-alloHCT and autoHCT was 60 (range 55-76) years and 61 (range 55-76) years, respectively. The proportion of Philadelphia chromosome positive (Ph(+)) ALL was 71% and 63%, respectively. Measurable residual disease (MRD)-positive status at the time of HCT was reported in 35% and 21% patients, respectively (p=0.002). Busulphan and fludarabine (BuFlu) was the most frequently used conditioning regimen in the RIC-alloHCT setting (34%) while a combination of 12 Gy total body irradiation/cyclophosphamide (TBI12Gy/Cy) was most frequent in the autoHCT group (33%). RESULTS: The engraftment rate was 99% after RIC-alloHCT and 96% after autoHCT (p=0.01) while median time to neutrophil recovery was 16 days and 12 days, respectively (p<0.001), respectively. With a median follow-up of 57 months, the probabilities of leukemia-free survival (LFS) and overall survival (OS) at 5 years were 39% versus 34% (p=0.11) and 45% vs. 42% (p=0.23), respectively. The incidence of relapse (RI) and non-relapse mortality (NRM) were 41% vs. 51% (p=0.22) and 25% vs. 10% (p=0.001), respectively. In a multivariate model, using autoHCT as reference, the risk of NRM was increased for MSD-HCT (HR=2.1, p=0.02) and MUD-HCT (HR=3.08, p<0.001), which for MUD-HCT translated into a decreased chance of LFS (HR=1.55, p=0.01) and OS (HR=1.62, p=0.008). For MSD-HCT there was a tendency towards decreased LFS (HR=1.31, p=0.11) and OS (1.29, p=0.15) when compared to autoHCT. Among other prognostic factors, the risk of relapse was decreased for Ph(+) ALL compared to Ph(-) B-ALL (HR=0.7, p=0.04) which was accompanied by improved OS (HR=0.74, p=0.04). Finally, the risk of relapse was increased for patients with detectable MRD (HR=1.38, p=0.04) without significant effect on survival. CONCLUSIONS: Results of autoHCT for patients with ALL aged above 55 years in CR1 and with MRD negativity pre-transplant are encouraging. This option may be a valuable alternative to RIC-alloHCT and is associated with an improved OS compared to transplantations from MUD. Our observations require verification in prospective trials in the context of currently available novel agents and technologies, including blinatumomab, inotuzumab ozogamicin and CAR-T cells. Figure. Results of RIC-alloHCT and autoHCT for patients with ALL in CR1 aged >55 years Figure Disclosures Labopin: Jazz Pharmaceuticals: Honoraria. Blaise:Jazz Pharmaceuticals: Honoraria. Forcade:Novartis: Other: Travel grant for congress; Sanofi: Other: Travel grant for congress; JAZZ: Other: Travel grant for congress; NEOVII: Other: Travel grant for congress; Gilead: Speakers Bureau. Yakoub-Agha:Janssen: Honoraria; Gilead/Kite: Honoraria, Other: travel support; Novartis: Honoraria; Celgene: Honoraria; Jazz Pharmaceuticals: Honoraria. Mohty:Sanofi: Consultancy, Honoraria, Research Funding, Speakers Bureau; Stemline: Consultancy, Honoraria, Research Funding, Speakers Bureau; Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau; BMS: Consultancy, Honoraria, Research Funding, Speakers Bureau; Jazz Pharmaceuticals: Consultancy, Honoraria, Research Funding, Speakers Bureau; Amgen: Consultancy, Honoraria, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Research Funding, Speakers Bureau; GSK: Consultancy, Honoraria, Research Funding, Speakers Bureau; Takeda: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau.

Prognostic analysis of allogeneic hematopoietic stem cell transplantation for Philadelphia chromosome-positive acute lymphoblastic leukemia in complete remission in the era of tyrosine kinase inhibitors

目的探讨在酪氨酸激酶抑制剂（TKI）时代Ph染色体阳性急性淋巴细胞白血病（Ph+ALL）在完全缓解（CR）状态下行异基因造血干细胞移植（allo-HSCT）的预后和影响因素。方法回顾性分析2012年5月至2017年5月河北燕达陆道培医院收治的116例在CR状态下行allo-HSCT的Ph+ALL患者的预后及其影响因素。结果116例患者中男72例，女44例。中位年龄20（4～64）岁。同胞全相合移植21例，亲缘单倍型移植77例，非血缘移植18例。5年总生存（OS）率为73.2％（95％CI 63.8％～80.5％），其中诊断至移植间隔时间<180 d的亚组5年OS率为87.5％。5年无病生存（DFS）率为61.4％（95％CI 51.8％～69.7％）。5年细胞形态及分子学水平复发累积发生率为18.5％（95％CI 12.6％～27.3％）。5年移植相关死亡率（TRM）为19.9％（95％CI 13.8％～28.7％）。多因素分析显示，15～39岁（HR＝2.730，P＝0.044）、诊断至移植间隔时间≥180 d（HR＝4.534，P＝0.010）、发生Ⅲ～Ⅳ度急性移植物抗宿主病（aGVHD）（HR＝7.558，P＝0.000）是影响患者OS的不利因素；发生局限型慢性移植物抗宿主病（cGVHD）是影响患者OS的有利因素（HR＝0.300，P＝0.034）。而性别、起病时WBC（<30×109/L，≥30×109/L）、BCR-ABL融合基因类型、体细胞突变类型、移植前状态（CR1，>CR1）、移植前微小残留病（MRD）水平（MRD阴性，MRD阳性）、预处理方案（全身照射方案，白消安为基础方案）、预处理方案强度、移植类型、GVHD预防方案（环孢素A，他克莫司）、抗胸腺细胞免疫球蛋白的种类、巨细胞病毒和EB病毒血症的有无对OS的影响无统计学意义。结论TKI时代Ph+ALL在CR状态下行allo-HSCT时，影响生存的因素有年龄、诊断至移植间隔时间和发生重度aGVHD。

Ponatynib w leczeniu ostrej białaczki limfoblastycznej z obecnością chromosomu Filadelfia

Acute lymphoblastic leukemia (ALL) with the presence of the Philadelphia chromosome (Ph+) is one of the most aggressive tumors. Improvement in the prognosis of patients occurred with the introduction of tyrosine kinase inhibitors (TKI), which are currently used in combination with chemotherapy. Such treatment is associated with over 90% chance of achieving complete remission. Next generations of TKI allow achieving deeper and longer responses, which translates into event-free and overall survival. Ponatinib (3 rd generation TKI) is currently registered in the treatment of patients with Ph(+) ALL after intolerance and/or resistance of first and second generation TKI or in patients with T315I mutation of BCR-ABL1 kinase. Work on assessing the efficacy and safety of ponatinib in the first line of therapy is ongoing.

Transplant Characteristics and Outcomes of Philadelphia (Ph)-like Acute Lymphoblastic Leukemia (ALL)

<h3>Background</h3> Ph-like ALL is a recently recognized high risk B-ALL subgroup, defined by a gene expression profile similar to Ph (+) ALL that activates tyrosine kinase or cytokine receptor signaling. Several studies have described inferior outcomes with conventional chemotherapy and although small series suggest that it is responsive to targeted therapies, stem cell transplant (SCT) remains the only potentially curative option. However, the SCT outcomes of Ph-like ALL are not well defined and it remains unknown whether SCT is able to overcome the adverse prognosis associated with it. <h3>Methods</h3> We retrospectively identified 77 adult patients with Ph (-) B-ALL that received a SCT at Memorial Sloan Kettering, 2008-2018, and reviewed their cytogenetic and molecular reports at diagnosis. Testing for Ph-like ALL is employed in an algorithmically driven approach at our institution including cytogenetics, chromosomal microarray and next generation sequencing (NGS). Ph-like ALL was defined by the presence of abnormalities including <i>ABL</i>-class fusions that phenocopy <i>BCR-ABL</i> (<i>ABL1, ABL2, CSF1R</i> and <i>PDGFRB</i>) or alterations of <i>CRFL2, JAK2</i> and <i>EPOR</i> that activate JAK/STAT signaling. We then analyzed the SCT outcomes of Ph-like patients and compared them to Ph (-) patients. <h3>Results</h3> A Ph-like signature was identified in 13 of 77 (16.9%) patients by NGS (n=7), cytogenetics (n=1), both NGS/cytogenetics (n=2) or microarray (n=3). Median age of all 13 patients was 42.7 (range 23.9-67.7) years and 6 (46.2%) patients were adolescents/young adults (<40 years). Ph-like abnormalities included mutations of <i>NRAS</i> (n=3), <i>JAK2</i> (n=2), <i>NF1</i> (n=2), <i>FLT3 ITD</i> (n=1), and <i>IL7R</i> (n=1), fusions involving <i>CRFL2</i> (n=3) or <i>PDGFRB</i> (n=1) and <i>ABL1</i> rearrangements (n=1). Three patients had concomitant <i>IKZF1</i> mutations. Most patients received myeloablative conditioning (n=8, 61.5%) and the most common donor type was matched unrelated (n=7, 53.8%) (Fig 1). At a median follow up of 17.3 (range 0.5-109.3) months, overall survival (OS) was comparable between the Ph-like and Ph (-) groups with one-year OS rates of 74% and 70% (p=0.534) respectively (Fig 2A). Causes of death in Ph-like patients were relapse (n=2) and infectious complications (n=1). One-year cumulative incidence of relapse was 32.7% in Ph-like vs 17.3% in Ph (-) patients, however it did not reach statistical significance (p=0.94, Fig 3). Among the 4 Ph-like patients who relapsed, 1 had refractory disease prior to SCT, 2 were in second remission and 1 in first remission. One-year disease free survival was also comparable between the 2 groups (67% for Ph-like vs 65% for Ph (-), p=0.719) (Fig 2B). Finally, acute GVHD rates by day 100 were 69.2% in Ph-like (n=9) vs 53.1% (n=34) in Ph (-) patients (p=0.3). <h3>Conclusions</h3> Our findings suggest that SCT overcomes the adverse prognosis associated with the Ph-like signature and should be incorporated in the treatment of patients with this disease entity.

Salvage and bridging to allogeneic hematopoietic cell transplantation with ponatinib in patients with relapsed or refractory Philadelphia chromosome-positive leukemia.

A single-center retrospective study was performed with consecutive patients who received salvage therapy using ponatinib for the aim of allogeneic hematopoietic cell transplantation (HCT) for relapsed or refractory Ph-leukemia between January 2017 and July 2018. A total of ten patients-seven with Ph-acute lymphoblastic leukemia (ALL) and three with chronic phase (CP)/accelerated phase chronic myeloid leukemia (CML)-were eligible. Eight patients had a history of a single tyrosine kinase inhibitor (TKI) use prior to ponatinib. Any mutation of the tyrosine kinase domain was detected in eight patients, including seven of T315I. The median dose of ponatinib was 15mg with a median duration of 7weeks (range 4-23weeks). The median duration from the start of ponatinib to HCT was 54days (range 35-175days). Hematological remission was obtained in five Ph-ALL patients. Maintenance therapy of ponatinib was applied to five patients. No vascular occlusion event has occurred over this series of treatments. Salvage therapy with low-dose ponatinib appears to be safe and effective in patients with relapsed or refractory Ph-leukemia, which may immediately bridge to HCT.

Minimal Residual Disease (MRD) Status after Induction Therapy Is a Strong Prognostic Factor in the Treatment of Adult Ph (-) Acute Lymphoblastic Leukemia (ALL): Results of a Prospective Study (ALL MRD2008 Study)

IntroductionA clinical indication for allogeneic hematopoietic stem cell transplantation (HSCT) in adult Philadelphia-chromosome negative [Ph (-)] acute lymphoblastic leukemia (ALL) patients in complete remission 1 (CR1) remains to be clarified. Minimal residual disease (MRD) status has been reported to be a strong prognostic factor in adult ALL patients (Blood. 2006 107:1116, 2009 113:4153)( J Hematol Oncol. 2013 6:14). We prospectively monitored MRD status during induction and consolidation therapy in adult Ph (-) ALL patients to determine a clinical indication for HSCT.Materials & MethodsFrom December 2008 to November 2013, 103 adult ALL patients were enrolled in this study. Eligibility criteria included non-L3 ALL, 16-65 years of age, and adequate organ function. Of these patients, 95 were eligible for this study and 59 were Ph (-). The treatment protocol used in this study was modified CALGB 19802. Treatment consisted of 6 courses given in the order of A-B-C-A-B-C, followed by a maintenance phase. Induction chemotherapy (course A) consisted of cyclophosphamide (1,200 mg/m2), daunorubicin (60 mg/m2 x 3), vincristine (VCR) (1.3 mg/m2 (max 2mg) x 4), L-asparaginase (3,000 U/m2 x 6) and prednisolone. Granulocyte colony-stimulating factor was started on day 4 and continued until neutrophil recovery. Consolidation B consisted of mitoxantrone (10 mg/m2 x 2), cytarabine (2,000 mg/m2/day x 4) and intrathecal (IT) administration of methotrexate (MTX). Consolidation C consisted of VCR (1.3 mg/m2 (max 2mg) x 3) and MTX (1,500 mg/m2 x 3) with leucovorin rescue and IT MTX. Patients received maintenance chemotherapy on a monthly basis: prednisolone 60 mg/m2 on days 1-5, VCR (1.3mg/m2 (max 2mg) x 3) on day 1, oral MTX 20 mg/m2 weekly, and oral 6-mercaptopurine 60 mg/m2 daily. MRD status was evaluated after induction therapy (first course A) and after second consolidation therapy (first course C). When MRD statuses after the consolidation were positive, patients were supposed to proceed to HSCT whenever possible.ResultsAmong the 59 Ph-negative ALL patients, 51 patients (86%) could be monitored for MRD status, and the remaining 8 patients were not because of no clonal TCR/Ig targets or chimeric mRNA. The MRD status was determined by PCR analysis of major gene rearrangements and/or chimeric mRNAs (18 were positive for TCRγ, 16 for TCRδ, 13 for IgH, 1 for TCRγ and MLL-AF4, 1 for TCRγ and ETV6-RUNX1, 1 for IgH and MLL-AF4, and 1 for IgH and MLL-ENL). MRD quantifications were performed using ASO-primers with a sensitivity of ≤1 × 10−4, and MRD positivity was defined as a lower limit of detection of ≥1 × 10−3. The median follow-up time was 1597 days (range, 16-2870 days). A total of 51 patients included 29 males and 22 females, and their median age was 29 years ranging from 16 to 65. The median white blood cell count at presentation was 8.5 × 103/L (range 1.2-650.4). CR was achieved in 45 patients (88%). One patient died during induction due to intestinal bleeding. There were 29 survivors after the median follow-up period. The probability of 3-year OS and DFS in these patients with Ph-negative ALL was 69% (95%CI 54-80) and 50% (95%CI 36-63, respectively. In terms of CR1 status, MRD-negative patients after induction chemotherapy A in the first course (n = 17) showed a better 3-year DFS (65%) compared with MRD-positive patients (n = 31; 43%), as shown in Figure 1. The difference was not statistically significant (p = 0.07). There was no patient who proceeded to allogeneic HSCT among 17 MRD-negative patients after induction therapy in CR. In contrast, patients who were MRD-positive after induction but became MRD-negative after consolidation chemotherapy C in the first course (n = 11) showed a worse 3-year DFS compared with patients who were MRD-negative after induction chemotherapy A in the first course (45% vs. 65%, p = 0.08). Fourteen patients were MRD-positive after consolidation chemotherapy C in the first course. Among them, 5 patients proceeded to allogeneic HSCT in 1CR, and 9 did not. Three-year DFS with or without allogeneic HSCT were 60% (95%CI 13-88) vs 44% (95%CI 14-72, p=0.52), respectively.DiscussionThe present study indicates that MRD status after induction and consolidation therapies is a strong prognostic factor. Post-induction MRD-negative patients have been identified to have good-prognosis with chemotherapies, not suitable for up-front allogeneic HSCT. [Display omitted] DisclosuresTakamatsu:Taisho Toyama Pharmaceutical: Research Funding; TAIHO Pharmaceutical: Research Funding; Pfizer: Research Funding; Bristol-Myers Squibb: Research Funding; Ono Pharmaceutical: Research Funding; Astellas Pharma: Research Funding; Kyowa Hakko Kirin: Research Funding; Chugai Pharma: Research Funding; Takeda Pharmaceutical: Research Funding; Celgene: Honoraria. Akashi:Celgene: Research Funding, Speakers Bureau; Novartis pharma: Research Funding; Ono Pharmaceutical: Research Funding; Eisai: Research Funding; sanofi: Research Funding; Pfizer: Research Funding; Chugai Pharma: Research Funding; Kyowa Hakko Kirin: Research Funding, Speakers Bureau; Asahi-kasei: Research Funding; MSD: Research Funding; Otsuka Pharmaceutical: Research Funding; Taiho Pharmaceutical: Research Funding; Bristol-Myers Squibb: Research Funding, Speakers Bureau; Astellas Pharma: Research Funding; Eli Lilly Japan: Research Funding.

CDKN2A/p16INK4a DELETION IS NOT A POOR PROGNOSTIC FACTOR IN ADULT ACUTE LYMPHOBLASTIC LEUKEMIA PATIENTS TREATED ACCORDING TO PROTOCOL RALL-2009

Introduction. CDKN2A deletion is a frequent cytogenetic abnormality in acute lymphoblastic leukemia (ALL), ranging from 18 to 46 %, associating with Т-cell ALL, high WBC counts, splenomegaly, lymphadenopathy. In pediatric group of patient’s CDKN2A deletion was associated with poor event-free survival. The prognostic impact of CDKN2A deletion in adult ALL patients appear controversial. The aim of this study was to evaluate the prognostic impact of the CDKN2A deletion in adult patients with acute lymphoblastic leukemia, which were treated by RALL-2009. Materials and methods. We present the results of the CDKN2A deletion in 110 adult patients with newly diagnosed Ph-negative (Ph‒) ALL, which were treated by RALL-2009 (NCT01193933) since June 2009 till September 2016. Patients characteristics: the median age was 26 years (range 15–54), 65 (59 %) of the 110 patients had a B-precursor phenotype, 42 (38 %) had a T-cell phenotype, 3 (2.7 %) patients – biphenotypical ALL. Interphase fluorescence in situ hybridization (FISH) was performed for detection CDKN2A deletion, MLL, с-MYC rearrangement, TP53 deletion, t (1;19) (q23; p13.3)/TCF3-PBX1, t (12;21) (p13.2; q22.1)/ETV6-RUNX1 and iAMP21. The median follow-up was 31 months (0.5 to 80 months). Results. The prevalence of the CDKN2A deletion in all studied population was 24.3 % (27 cases). Our study demonstrated that CDKN2A deletion had no significant association with age, sex and blast cells immunophenotype. The analysis for T-ALL has detected that CDKN2A deletion was strongly associated with high WBC count (the median is 86 × 109/L; p = 0.006) and with high lactate dehydrogenase level (the median is 3062 IU; p = 0.0004). But in BCP-ALL cases similar correlation was not found. CDKN2A deletion didn’t have statistically significant impact on outcome of patients. OS for patients with BCP-ALL with and without deletion was 85 and 76 % (p = 0.35); DFS was 92 and 65 % (p = 0.07), respectively. OS for T-ALL patients with and without deletion was 90 and 80 % (p = 0.63); DFS was 100 and 82 % (p = 0.24), respectively. Conclusion: CDKN2A deletion is not adverse prognostic factor in adult ALL patients treated according to protocol RALL-2009.

Effect of IKZF1 deletions on signal transduction pathways in Philadelphia chromosome negative pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL).

BackgroundIKZF1 deletions are an unfavorable prognostic factor in children with Philadelphia chromosome positive (Ph+) as well as negative (Ph−) acute lymphoblastic leukemia (ALL). Although IKZF1 deletions occur in 10–15% of Ph− ALL cases, effects of IKZF1 deletions on signaling pathways in this group have not been extensively studied. Therefore, in this study we aimed to study the effect of IKZF1 deletions on active signal transduction pathways.MethodsMultiplex ligation-dependent probe amplification (MLPA) was used to determine IKZF1 deletions and other copy number alterations in 109 pediatric B-Cell Precursor ALL (BCP-ALL) patients. Kinase activity profiling of 45 primary Ph− BCP-ALL patients (31 IKZF1 wild type patients and 14 patients harboring an IKZF1 alteration) and western blot analysis of 14 pediatric BCP-ALL samples was performed to determine active signal transduction pathways.ResultsUnsupervised hierarchical cluster analysis of kinome profiles of 45 pediatric Ph− ALL cases showed no clustering based on IKZF1 status. Comparing the phosphorylation intensities of peptides associated with signaling pathways known to be involved in BCP-ALL maintenance, we did not observe differences between the two groups. Western blot analysis of 14 pediatric BCP-ALL samples showed large variations in phosphorylation levels between the different ALL samples, independent of IKZF1 status.ConclusionsBased on these results we conclude that, although IKZF1 deletions appear to be an important clinical prognostic factor, we were unable to identify a unique IKZF1 dependent protein expression signature in pediatric Ph− ALL and consequently no specific targets for future therapy of Ph−IKZF1 deleted BCP-ALL could be identified.Electronic supplementary materialThe online version of this article (doi:10.1186/s40164-015-0017-y) contains supplementary material, which is available to authorized users.

YM155 potently kills acute lymphoblastic leukemia cells through activation of the DNA damage pathway.

BackgroundNovel-targeted therapies are in rapid development for the treatment of acute lymphoblastic leukemia (ALL) to overcome resistance and decrease toxicity. Survivin, a member of the inhibitor of apoptosis gene family and chromosome passenger complex, is critical in a variety of human cancers, including ALL. A well-established suppressor of survivin has been the small molecule, YM155. Reports are identifying other mechanisms of action for YM155. Therefore, we sought to investigate the mode of action and role of YM155 for therapeutic use in the context of ALL.MethodsPrimary ALL samples and ALL cell lines were interrogated with YM155 to identify drug sensitivity. Ph+ALL harboring the BCR-ABL1 oncogene were tested for any interaction with YM155 and the multi-kinase inhibitor dasatinib. Representative ALL cell lines were tested to identify the response to YM155 using standard biochemical assays as well as RNA expression and phosphorylation arrays.ResultsALL samples exhibited significant sensitivity to YM155, and an additive response was observed with dasatinib in the setting of Ph+ALL. ALL cells were more sensitive to YM155 during S phase during DNA replication. YM155 activates the DNA damage pathway leading to phosphorylation of Chk2 and H2AX. Interestingly, screening of primary patient samples identified unique and exquisite YM155 sensitivity in some but not all ALL specimens.ConclusionThese results are the first to have screened a large number of primary patient leukemic samples to identify individual variations of response to YM155. Our studies further support that YM155 in ALL induces DNA damage leading to S phase arrest. Finally, only subsets of ALL have exquisite sensitivity to YM155 presumably through both suppression of survivin expression and activation of the DNA damage pathway underscoring its potential for therapeutic development.Electronic supplementary materialThe online version of this article (doi:10.1186/s13045-015-0132-6) contains supplementary material, which is available to authorized users.

Toward Effective Targeted Therapy for the Treatment of Adult Acute Lymphoblastic Leukemia

Through the effectiveness of combination chemotherapy and allogeneic stem cell transplantation (ASCT), the cure of acute lymphoblastic leukemia (ALL) in children evolved from the 1970s from an anecdotal wonder to a quantifiable reality. Although giving less spectacular results than those seen in children, these therapeutic approaches have been applied to adults over the last two decades, leading to an improved response rate and survival [1]. Retrospective comparisons demonstrating that adolescents with ALL significantly benefit from pediatric rather than adult chemotherapy regimens yielded to the recent development of pediatric-inspired regimens for adult ALL involving greater dose densities of many chemotherapeutic agents, such as l-asparaginase, vincristine, corticosteroids and methotrexate [2]. However, additional gains are unlikely to be achieved by simply intensifying therapy further, due to the offset of unacceptable toxicities. Furthermore, new procedures for ASCT modestly improve the outcome of adult ALL, while introducing higher risks of acute and late complications. There was therefore a clear and compelling rationale for developing therapies that specifically target the molecular abnormalities that cause leukemia. Encouraging signs have recently emerged with the development of novel therapeutic agents, opening a new era of treatment in adult ALL. Several points of intervention have been identified that may respond to targeted drugs. Concomitantly, the biology of leukemia stem cell (eradication of which is considered as the relevant goal of leukemia therapy) was better understood. Several primary studies with targeted agents have demonstrated impressive clinical activity, even in heavily pretreated patients. Others have demonstrated synergistic effects with chemotherapy and the feasibility of such combinations in clinical trials. The era of targeted therapy for ALL started about 15 years ago with the development of the first inhibitor of tyrosine kinase (TKI), imatinib mesylate [3]. Imatinib mesylate and then the other inhibitors of the ABL tyrosine kinase activity of the fusion protein BCR-ABL have revolutionized the treatment of Philadelphia chromosome-positive (Ph) ALL [4,5]. TKIs are now integral components of therapy for Ph ALL. The current consensus is that they improve patient

Allogeneic HCT with Reduced Intensity Conditioning Versus Autologous HCT for >55 Years Old Patients with Acute Lymphoblastic Leukemia in First Complete Remission: An Analysis from Acute Leukemia Working Party of the EBMT

BACKGROUNDThe prognosis of patients >55 years old with acute lymphoblastic leukemia (ALL) is poor with reported 5-year survival not exceeding 20%. Disease relapse is a major cause of treatment failure. These patients are usually considered ineligible for standard myeloablative allogeneic hematopoietic cell transplantation (alloHCT) due to frequent presence of co-morbidities and higher rate of toxicities. Alternative strategies include reduced intensity(RIC)-alloHCT or autologous(auto)-HCT. However, the role of these treatment options has not been well established thus far. The aim of the current study was to retrospectively compare results of RIC-alloHCT and autoHCT in ALL >55 years old and to identify factors affecting outcome. Data were derived from the registry of the European Group for Blood and Marrow Transplantation. PATIENTS267 patients treated with RIC-alloHCT from either HLA-identical sibling (n=154) or matched unrelated donor (n=113) and 179 treated with autoHCT in first complete remission between 2000 and 2011 have been included in this analysis. Median age in both groups was 60 (55-74)y and 60 (55-76)y, respectively, while median interval from diagnosis to HCT was 5.9 months and 6.6 months, respectively. The proportion of Ph(+) ALL among those with reported cytogenetics was 71% and 66%, respectively. RESULTSWith a median follow-up of 33 months, the probability of OS at two years was 44% for RIC-alloHCT and 57% for autoHCT (p=0.02), while LFS rates were 34% and 41%, respectively (p=0.06). The advantage in favor of autoHCT was significant for Ph(-) ALL (OS: 61% vs. 38%, p=0.02; LFS: 54% vs. 21%, p=0.005) while not for Ph(+) ALL (OS: 55% vs. 47%, p=0.6; LFS: 42% vs. 35%, p=0.4).Relapse incidence at two years was comparable for RIC-alloHCT and autoHCT (42% vs. 48%, p=0.39) while non-relapse mortality was significantly reduced for autoHCT (23% vs. 11%, respectively, p=0.002).In a multivariate analysis adjusted for recipient age and gender as well as interval from diagnosis to transplantation the use of autoHSCT was independently associated with reduced risk of mortality (HR=0.69, p=0.01), treatment failure (HR=0.76, p=0.03) and non-relapse mortality (HR=0.39; p=0.0004) with no effect on relapse incidence (HR=0.98, p=0.88).In the RIC-alloHSCT subgroup LFS was negatively affected by female donor/male recipient combination (HR=1.64, p=0.01). LFS rates for both sibling and MUD transplants were comparable (32+/-4% vs. 35+/-5%, p=0.18). The use of peripheral blood cells compared to bone marrow was associated with reduced risk of relapse (HR=0.5, p=0.03). In the autoHSCT setting there was a tendency to higher risk of treatment failure by increasing recipient age (HR=1.05, p=0.06). Other variables including type of conditioning (TBI-based vs. chemotherapy-based) did not affect survival in any of the study cohorts. CONCLUSIONSConsidering poor overall prognosis of ALL patients >55 years old, results of both RIC-alloHCT and autoHCT appear enhancing and both types of transplantation may be considered valuable treatment options. Potential advantage of autoHCT as suggested by results of our analysis should be further explored including data on disease-related prognostic factors and the status of minimal residual disease. Prospective studies are warranted to define final recommendations. DisclosuresNiederwieser:Novartis: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau; Gentium: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau; Amgen: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau.

Genotyping of Chimerical BCR-ABL1 RNA in Chronic Myeloid Leukemia by Integrated DNA Chip

Chronic myelogenous leukemia (CML) and Philadelphia chromosome-positive (Ph(+)) acute lymphoblastic leukemia (ALL) are associated with fusion of the BCR and ABL1 genes by chromosome translocation. The chimerical BCR-ABL1 gene encodes different fusion proteins that vary in size, depending on the breakpoint in the BCR region. Different types of fusion genes in CML and Ph(+) ALL are thought to be related to the clinical course and outcome of each patient. Currently, the genotypes are determined by PCR, followed by gel electrophoresis or DNA sequencing (among other methodologies). Our major aim was to develop a diagnostic method for CML genotyping by means of an integrated process of DNA microarray. Here, we describe a method of integrated multiplex reverse transcription, asymmetric PCR, and hybridization, all in the same reaction mixture in a chamber assembled on the surface of capture oligonucleotide probes immobilized on a glass slide. The integrated system successfully identified the four predominant types of chimerical BCR-ABL1 RNA (b3a2, b2a2, e1a2, and c3a2), which together account for 98% of CML cases. The integrated multiplex system also had a high sensitivity of detection (as little as 200 molecules of target RNA molecules). The integrated process saves time and effort, and it also the advantage of minimizing the steps needed for automated detection of different types of chimerical CML RNA.

Disparate In Vivo Efficacy of FTY720 in Xenograft Models of Philadelphia Positive and Negative B-lineage Acute Lymphoblastic Leukemia

Most patients with acute lymphoblastic leukemia (ALL) respond well to standard chemotherapy-based treatments. However a significant proportion of patients, particularly adult patients, relapse with the majority dying of leukemia. FTY720 is an immunosuppressive drug that was recently approved for the treatment of multiple sclerosis and is currently under pre-clinical investigation as a therapy for a number of hematological malignancies. Using human ALL xenografts in NOD/SCIDγc−/− mice, we show for the first time that three Ph+ human ALL xenografts responded to FTY720 with an 80±12% (p = 0.048) reduction in overall disease when treatment was commenced early. In contrast, treatment of mice with FTY720 did not result in reduced leukemia compared to controls using four separate human Ph− ALL xenografts. Although FTY720 reactivated PP2A in vitro, this reactivation was not required for death of Ph− ALL cells. The plasma levels of FTY720 achieved in the mice were in the high nanomolar range. However, the response seen in the Ph+ ALL xenografts when treatment was initiated early implies that in vivo efficacy may be obtained with substantially lower drug concentrations than those required in vitro. Our data suggest that while FTY720 may have potential as a treatment for Ph+ ALL it will not be a useful agent for the treatment of Ph− B-ALL.

Philadelphia chromosome-positive leukemia stem cells in acute lymphoblastic leukemia and tyrosine kinase inhibitor therapy

Leukemia stem cells (LSCs), which constitute a minority of the tumor bulk, are functionally defined on the basis of their ability to transfer leukemia into an immunodeficient recipient animal. The presence of LSCs has been demonstrated in acute lymphoblastic leukemia (ALL), of which ALL with Philadelphia chromosome-positive (Ph(+)). The use of imatinib, a tyrosine kinase inhibitor (TKI), as part of front-line treatment and in combination with cytotoxic agents, has greatly improved the proportions of complete response and molecular remission and the overall outcome in adults with newly diagnosed Ph(+) ALL. New challenges have emerged with respect to induction of resistance to imatinib via Abelson tyrosine kinase mutations. An important recent addition to the arsenal against Ph(+) leukemias in general was the development of novel TKIs, such as nilotinib and dasatinib. However, in vitro experiments have suggested that TKIs have an antiproliferative but not an antiapoptotic or cytotoxic effect on the most primitive ALL stem cells. None of the TKIs in clinical use target the LSC. Second generation TKI dasatinib has been shown to have a more profound effect on the stem cell compartment but the drug was still unable to kill the most primitive LSCs. Allogeneic stem cell transplantation (SCT) remains the only curative treatment available for these patients. Several mechanisms were proposed to explain the resistance of LSCs to TKIs in addition to mutations. Hence, TKIs may be used as a bridge to SCT rather than monotherapy or combination with standard chemotherapy. Better understanding the biology of Ph(+) ALL will open new avenues for effective management. In this review, we highlight recent findings relating to the question of LSCs in Ph(+) ALL.

Minimal Residual Disease Negative Status At the End of Induction Therapy Is a Potent Prognostic Marker in Adult Non-Ph Acute Lymphoblastic Leukemia: Results of the ALL MRD2002 Study

Abstract 2581 IntroductionA clinical indication for allogeneic hematopoietic stem cell transplantation (HSCT) in adult Philadelphia-chromosome negative [Ph (−)] acute lymphoblastic leukemia (ALL) patients in complete remission 1 (CR1) remains to be clarified. An international study showed that matched related donors HSCT for ALL in CR1 provides survival benefits for standard-risk ALL patients compared to chemotherapy (Blood. 2008 111:1827). Minimal residual disease (MRD) status has been reported to be a strong prognostic factor in adult ALL patients (Blood. 2006 107:1116, 2009 113:4153). We prospectively monitored MRD status during induction and consolidation therapy in adult Ph (−) ALL patients to determine a clinical indication for HSCT. Materials & MethodsFrom July 2002 to August 2008, 110 adult ALL patients were enrolled in this study. Eligibility criteria included non-L3 ALL, 16–65 years of age, and adequate organ function. Of these patients, 101 were eligible for this study and 59 were Ph (−). The treatment protocol used in this study was modified CALGB 19802. Treatment consisted of 6 courses given in the order of A-B-C-A-B-C, followed by a maintenance phase. Induction chemotherapy (course A) consisted of cyclophosphamide (1,200 mg/m2), daunorubicin (60 mg/m2 × 3), vincristine (VCR) (1.3 mg/m2 (max 2mg) × 4), L-asparaginase (3,000 U/m2 × 6) and prednisolone. Granulocyte colony-stimulating factor was started on day 4 and continued until neutrophil recovery. Consolidation B consisted of mitoxantrone (10 mg/m2 × 2), cytarabine (2,000 mg/m2/day × 4) and intrathecal (IT) administration of methotrexate (MTX). Consolidation C consisted of VCR (1.3 mg/m2 (max 2mg) × 3) and MTX (1,500 mg/m2 × 3) with leucovorin rescue and IT MTX. Patients received maintenance chemotherapy on a monthly basis: prednisolone 60 mg/m2 on days 1–5, VCR (1.3mg/m2 (max 2mg) × 3) on day 1, oral MTX 20 mg/m2 weekly, and oral 6-mercaptopurine 60 mg/m2 daily. MRD status was evaluated after induction therapy (first course A) and after second consolidation therapy (first course C). When MRD statuses after the consolidation were positive, patients were supposed to proceed to HSCT whenever possible. ResultsA total of 59 patients were Ph (−). MRD status of 41 of these patients (69.5%) could be monitored by the major rearrangement patterns of TCRƒÁ, TCRƒÁ, and IgƒÈ chain genes, and secondarily for IgH gene rearrangements (Blood. 1991 77:331), and chimeric RNA analysis (TCRƒÁ n=14, TCRƒÁ n=9, IgƒÈ n=6, IgH n=1, other n=1, E2A-PBX1 n=3, MLL-AF4 n=1). There were 21 male and 20 female patients. The median age was 31.0 (range 17–63 years). The median white blood cell count at presentation was 10,900/ml (range 1,000–408,700). A total of 36 patients (85.7%) achieved CR. The probability of 3-year overall survival and progression-free survival (PFS) were 59.3 % and 48.9 %, respectively. In terms of CR1 status, patients who were MRD (−) after induction therapy (first course A)(n = 22) had a significantly better 3-year PFS compared with those who were MRD (+)(n = 13)(72.2 % vs. 33.6 %, p = 0.011). Those MRD (−) patients also had a significantly lower 3-year probability of relapse compared with MRD (+) patients (27.8 % vs. 58.0 %, p = 0.031). Patients who were MRD (+) after consolidation therapy (n=3) had an ominous prognosis without HSCT (3-year PFS 0%), while the MRD (+) patients with HSCT (n=3) had 66.7 % 3-year PFS. On multivariate analysis, age (≥35 vs. <35 years, HR 4.535, p = 0.007) and MRD status after induction therapy (+ vs. -, HR 5.250, p = 0.009) were significant prognostic factors, whereas WBC count (≥30,000 vs. <30,000, HR 1.502, p = 0.498) was not. DiscussionHSCT for CR1 ALL has the greatest anti-ALL activity. However, HSCT has higher morbidity and mortality rates than chemotherapy. Thus, HSCT should be avoided in patients who have good prognosis with chemotherapy alone. Our results show that patients with molecular remission after induction therapy have an excellent PFS without HSCT, and patients who are MRD (+) after several consolidation therapies have very poor PFS without HSCT. The present study indicates that MRD status after induction and consolidation therapies is a significant prognostic factor. MRD monitoring is useful to determine a clinical indication of HSCT for patients who achieve CR1. For CR1 patients with MRD (+) status after several consolidation therapies, further intensification of chemotherapy may be possible when HSCT is not a suitable option. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

IGFBP7 participates in the reciprocal interaction between acute lymphoblastic leukemia and BM stromal cells and in leukemia resistance to asparaginase

The interaction of acute lymphoblastic leukemia (ALL) blasts with bone marrow (BM) stromal cells (BMSCs) has a positive impact on ALL resistance to chemotherapy. We investigated the modulation of a series of putative asparaginase-resistance/sensitivity genes in B-precursor ALL cells upon coculture with BMSCs. Coculture with stromal cells resulted in increased insulin-like growth factor (IGF)-binding protein 7 (IGFBP7) expression by ALL cells. Assays with IGFBP7 knockdown ALL and stromal cell lines, or with addition of recombinant rIGFBP7 (rIGFBP7) to the culture medium, showed that IGFBP7 acts as a positive regulator of ALL and stromal cells growth, and significantly enhances in-vitro resistance of ALL to asparaginase. In these assays, IGFBP7 function occurred mainly in an insulin- and stromal-dependent manner. ALL cells were found to contribute substantially to extracellular IGFBP7 levels in the conditioned coculture medium. Diagnostic BM plasma from children with ALL had higher levels of IGFBP7 than controls. IGFBP7, in an insulin/IGF-dependent manner, enhanced asparagine synthetase expression and asparagine secretion by BMSCs, thus providing a stromal-dependent mechanism by which IGFBP7 protects ALL cells against asparaginase in this coculture system. Importantly, higher IGFBP7 mRNA levels were associated with lower leukemia-free survival (Cox regression model, P=0.003) in precursor B-cell Ph(-) ALL patients (n=147) treated with a contemporary polychemotherapy protocol.

Immunocompetent cell functions in Ph+ acute lymphoblastic leukemia patients on prolonged Imatinib maintenance treatment.

Imatinib mesylate (Imatinib) is a potent inhibitor of defined tyrosine kinases and is effectively used for the treatment of malignancies characterized by the constitutive activation of these tyrosine kinases, such as Philadelphia chromosome-positive (Ph(+)) leukemias and gastrointestinal stromal tumors. Suppressive as well as stimulating effects of this drug on T lymphocytes or dendritic cells (DC), which play a major role in immune tumor surveillance, have been reported. For this reason, we questioned whether Imatinib could also affect the phenotypic and functional properties of these subpopulations in Ph(+) acute lymphoblastic leukemia (ALL) patients on prolonged Imatinib maintenance treatment. Circulating T lymphocytes and NK cells from Imatinib-treated Ph(+) ALL patients showed a subset distribution comparable to that of healthy donors. In addition, T-cell immunomodulant cytokine production (IFN-γ, TNF-α) and proliferative responses were not impaired. A normal monocyte-derived DC differentiation and apoptotic body loading capacity was also observed in the majority of Imatinib-treated patients. In contrast, an impairment in the DC intracellular production of IL-12 was recorded, although this was not observed when normal DC were exposed in vitro to Imatinib. Finally, in vivo Imatinib treatment did not affect the T-lymphocyte proliferation and IFN-γ production induced by leukemic apoptotic body-loaded DC, underling the potential capability of these cells to generate a specific immune response against tumoral antigens. Taken together, these findings provide evidence that immunotherapeutic approaches aimed at controlling residual disease in Ph(+) ALL patients in hematologic remission are not jeopardized by the long-term administration of Imatinib.

Reduced Intensity Conditioning with Allogeneic Hematopoietic Cell Transplantation for the Treatment of High-Risk Acute Lymphoblastic Leukemia.

Abstract 1210Poster Board I-232Allogeneic hematopoietic cell transplantation (HCT) with a conventional, high intensity conditioning regimen is an established approach for potentially curing patients (pts) with high-risk acute lymphoblastic leukemia (ALL). However, many pts are not candidates for high intensity conditioning HCT. The use of a reduced intensity conditioning (RIC) for ALL may provide an opportunity to decrease the toxicity of an intense conditioning regimen yet maintain the potential graft vs. leukemia effect. Here we describe the transplantation course and overall survival (OS) of 50 consecutive pts with high-risk ALL that were treated in a multi-center protocol of RIC and allogeneic HCT between February 2000 and August 2008. The median age was 56 (range, 7-69) years. All pts had cytogenetic analysis of bone marrow (BM) at diagnosis. 26 pts had Philadelphia chromosome positive (Ph+) ALL: 18 were in first complete remission (CR1) and 8 were in CR>1 at the time of HCT. 24 pts had Ph–ALL, 12 pts were in CR1 and 12 pts were in CR>1. Pts. were conditioned with fludarabine 90mg/m2 and 2 Gy total body irradiation. Nine pts received peripheral blood stem cells (PBSC) from HLA-identical siblings, 41 pts received grafts from unrelated donors (35 HLA-matched PBSC, 1 BM and 5 received 1-HLA-Ag mismatched PBSC). After the introduction of imatinib mesylate, 19 of the 26 pts with Ph+ALL participated in a study evaluating the safety and efficacy of imatinib starting at day +15 after HCT. Post-grafting immunosuppression consisted of combined mycophenolate mofetil and cyclosporine. Median follow up for surviving pts was 31 months (range, 12-91). One pt had graft rejection (BM recipient). 25 pts (50%) and 4 pts (8%) developed grades 2 and 3-4 acute graft-versus-host disease (GVHD), respectively. Chronic GVHD occurred in 24 pts (53% of pts surviving > 100 days); 15 pts (30%) developed extensive chronic GVHD. 19 pts (38%) relapsed at a median of 4.5 (range, 0.4-59) months. Non relapse mortality (NRM) at 2 and 5 years was 26% and 31%, respectively. Progression-free survival was very similar to OS. For all 50 pts, OS at 2 and 5 years was 37% and 27%, respectively. For pts in CR1 (n=30), OS was 52% and 41%, respectively. In contrast, OS for pts >CR1 (n=20) was significantly lower (13% and 7%, respectively, p=.003). For pts with Ph–ALL, OS was 29%, unchanged at both 2 and 5 years. Those in CR1 had improved OS compared with pts >CR1 (48% vs. 11% unchanged at both 2 and 5 years, respectively, p=0.07, Figure). OS for the 26 pts with Ph+ALL at 2 and 5 years was 45% and 27%, respectively. OS at 2 and 5 years for pts treated with imatinib after HCT was 52% and 43%, respectively, this was superior to the OS for pts with Ph+ALL that did not receive imatinib (p=0.03, Figure). For Ph+ALL pts in CR1 who had no evidence of minimal residual disease (MRD negative, detection by flow cytometry and FISH) prior to HCT and received imatinib (n=12), the OS was 67%, unchanged at both 2 and 5 years. In contrast, the pts with MRD negative Ph+ALL in CR1 who did not receive imatinib (n=4) had OS at 2 and 5 years of 50% and 0%, respectively. Imatinib after HCT was well tolerated: 3 pts required early stopping of imatinib due to associated reversible toxicity. We conclude that RIC with allogeneic HCT is a feasible treatment option that offers durable disease control, particularly for high-risk pts in CR1. The combination of post-transplant imatinib with RIC for Ph+ALL contributed to a substantially improved OS. [Display omitted] Disclosures:Off Label Use: Imatinib - post-grafting treatment. Mycophenolate mofetil - immunosuppression after HCT.

The homeobox gene CDX2 is aberrantly expressed and associated with an inferior prognosis in patients with acute lymphoblastic leukemia

Molecular characterization of acute lymphoblastic leukemia (ALL) has greatly improved the ability to categorize and prognostify patients with this disease. In this study, we show that the proto-oncogene CDX2 is aberrantly expressed in the majority of cases with B-lineage ALL and T-ALL. High expression of CDX2 correlated significantly with the ALL subtype pro-B ALL, cALL, Ph(+) ALL and early T-ALL. Furthermore, high expression of CDX2 was associated with inferior overall survival and showed up as a novel and strong risk factor for ALL in bivariate analysis. Functional analyses showed that overexpression of Cdx2 in murine bone marrow progenitors perturbed genes involved in lymphoid development and that depletion of CDX2 in the human ALL cell line Nalm6 inhibited colony formation. These data indicate that aberrant CDX2 expression occurs frequently and has prognostic impact in adult patients with ALL.

Allogeneic Transplantation for Pediatric Acute Lymphoblastic Leukemia: The Emerging Role of Peritransplantation Minimal Residual Disease/Chimerism Monitoring and Novel Chemotherapeutic, Molecular, and Immune Approaches Aimed at Preventing Relapse

Although improved donor sources and supportive care have decreased transplantation-related mortality over the past decade, relapse remains the principal cause of failure after allogeneic transplantation for high-risk pediatric acute lymphoblastic leukemia (ALL). Emerging tools of minimal residual disease (MRD) and chimerism monitoring before and after transplantation have defined those children at highest risk for relapse and provide the opportunity for intervention to prevent relapse. Specific methods aimed at decreasing relapse include the use of intensive treatment before transplantation to increase the percentage of patients undergoing the procedure with negative MRD, optimal transplantation preparative regimens, and posttransplantation interventions with targeted or immunologic therapy. Early data demonstrate decreased relapse with the use of sirolimus for all types of ALL and imatinib for ALL with the Philadelphia chromosome (Ph(+) ALL) after transplantation. Patients with increasing chimerism or MRD have been shown to benefit from early withdrawal of immune suppression or donor lymphocyte infusion. Finally, various targeted immunologic therapies, including monoclonal antibodies, killer cell immunoglobulin-like receptor mismatching, natural killer cell therapy, and targeted T cell therapies, are emerging that also could have an affect on relapse and improve survival after transplantation for pediatric ALL.