Genomic CDKN2A/2B deletions in adult Ph+ ALL are adverse despite allogeneic stem cell transplantation.

We investigated the role of copy number alterations to refine risk stratification in adult Philadelphia chromosome positive (Ph)+ acute lymphoblastic leukemia (ALL) treated with tyrosine kinase inhibitors (TKIs) and allogeneic stem cell transplantation (aSCT). Ninety-seven Ph+ ALL patients (median age 41 years; range 18-64 years) within the prospective multicenter German Multicenter ALL Study Group studies 06/99 (n = 8) and 07/2003 (n = 89) were analyzed. All patients received TKI and aSCT in first complete remission (CR1). Copy number analysis was performed with single nucleotide polymorphism arrays and validated by multiplex ligation-dependent probe amplification. The frequencies of recurrently deleted genes were: IKZF1, 76%; CDKN2A/2B, 45%; PAX5, 43%; BTG1, 18%; EBF1, 13%; ETV6, 5%; RB, 14%. In univariate analyses, the presence of CDKN2A/2B deletions had a negative impact on all endpoints: overall survival (P = .023), disease-free survival (P = .012), and remission duration (P = .036). The negative predictive value of CDKN2A/2B deletions was retained in multivariable analysis along with other factors such as timing of TKI therapy, intensity of conditioning, achieving remission after induction phase 1 and BTG1 deletions. We therefore conclude that acquired genomic CDKN2A/2B deletions identify a subgroup of Ph+ ALL patients, who have an inferior prognosis despite aSCT in CR1. Their poor outcome was attributable primarily to a high relapse rate after aSCT.

Ponatinib in the Treatment of Chronic Myeloid Leukemia and Philadelphia Chromosome-Positive Acute Leukemia: Recommendations of a German Expert Consensus Panel with Focus on Cardiovascular Management.

Treatment of chronic myeloid leukemia (CML) and Philadelphia chromosome-positive acute leukemia (Ph+ ALL) has been revolutionized with the advent of tyrosine kinase inhibitors (TKIs). Most patients with CML achieve long-term survival similar to individuals without CML due to treatment with TKIs not only in frontline but also in further lines of therapy. The third-generation TKI ponatinib has demonstrated efficacy in patients with refractory CML and Ph+ ALL. Ponatinib is currently the most potent TKI in this setting demonstrating activity against T315I mutant clones. However, ponatinib's safety data revealed a dose-dependent, increased risk of serious cardiovascular (CV) events. Guidance is needed to evaluate the benefit-risk profile of TKIs, such as ponatinib, and safety measures to prevent treatment-associated CV events. An expert panel of German hematologists and cardiologists summarize current evidence regarding ponatinib's efficacy and CV safety profile. We propose CV management strategies for patients who are candidates for ponatinib.

A Multicentre, Randomized Trial in Adults with de novo Philadelphia Chromosome-Positive Acute Lymphoblastic Leukaemia to Assess the Efficacy of Ponatinib versus Imatinib in Combination with Low-Intensity Chemotherapy, to Compare End of Therapy with Indication for Stem Cell Transplantation versus Tyrosine Kinase Inhibitor, Blinatumomab, and Chemotherapy in Optimal Responders, and to Evaluate Blinatumomab in Suboptimal Responders (GMALL-EVOLVE).

INTRODUCTION: Philadelphia chromosome-positive acute lymphoblastic leukaemia (Ph+ALL) is treated as standard of care (SoC) by imatinib-based treatment combined with induction and consolidation chemotherapy followed by allogeneic stem cell transplantation (SCT) in first remission. The German Multicenter ALL Study Group for Adult ALL (GMALL) reports about a trial to evaluate the impact of ponatinib-based therapy, blinatumomab treatment for suboptimal responders, and the possibility of omission of SoC Allo SCT in optimal responders entitled GMALL-EVOLVE. METHODS: Herein, imatinib is randomized versus ponatinib as frontline treatment combined with chemotherapy, optimal responders also get randomized between SCT and chemo-immunotherapy, and suboptimal responders receive immunotherapy before SCT. The trial is registered under the EudraCT number 2022-000760-21. CONCLUSION: This trial will answer several major questions in the treatment of Ph+ALL.

Expression of IGFBP7 in acute leukemia is regulated by DNA methylation.

The important role of insulin-like growth factor binding protein 7 (IGFBP7) as a tumor suppressor in solid tumors has been revealed in several studies. Interestingly, in a recent study IGFBP7 was also shown to be aberrantly expressed in acute leukemia. Moreover, in acute T-lymphoblastic leukemia (T-ALL), high IGFBP7 expression predicts primary therapy resistance. In order to elucidate the mechanisms underlying aberrant IGFBP7 expression, we used pyrosequencing technology to investigate the DNA methylation of IGFBP7 in 109 T-ALL patient samples. Aberrant methylation was shown and hypomethylation was associated with an early immunophenotype and co-expression of the stem cell markers CD117 (P < 0.001) and CD34 (P < 0.001). In concordance, gene expression profiles of 86 T-ALL patients revealed upregulation of stem cell markers (CD34 and CD133) as well as genes associated with poor outcome and pathogenesis of leukemia (MN1, BAALC, FLT3) in the high IGFBP7 expression group. In conclusion, aberrant IGFBP7 expression is regulated by DNA methylation in acute leukemia. Hypomethylation of the gene is likely to characterize an immature and a more malignant subtype of the disease.

Prognostic implications of mutations and expression of the Wilms tumor 1 (WT1) gene in adult acute T-lymphoblastic leukemia.

BACKGROUND: The role of the Wilms tumor 1 gene (WT1) in acute leukemias has been underscored by mutations found in acute myeloid leukemia identifying patients with inferior survival. Furthermore, aberrant expression of WT1 in acute myeloid leukemia was associated with an increased risk of relapse. No larger studies have performed a combined approach including WT1 mutation and expression analyses in acute T-lymphoblastic leukemia. DESIGN AND METHODS: We analyzed the WT1 mutations and the expression status in a total of 252 consecutive adult patients with newly diagnosed T-lymphoblastic leukemia, who were registered on the GMALL 06/99 and 07/03 protocols and had sufficient material available. The GMALL protocols included intensive chemotherapy as well as stem cell transplantation according to a risk-based model with indication for stem cell transplantation in first complete remission for early and mature T-lymphoblastic leukemia patients; patients with thymic T-lymphoblastic leukemia were allocated to a standard risk group and treated with intensive chemotherapy. RESULTS: Twenty of the 238 patients analyzed had WT1 mutations (WT1mut) in exon 7. WT1mut cases were characterized by immature features such as an early immunophenotype and higher WT1 expression. In thymic T-lymphoblastic leukemia, WT1mut patients had an inferior relapse-free survival compared to WT1 wild-type patients. T-lymphoblastic leukemia patients with aberrant WT1 expression (high or negative) showed a higher relapse rate and an inferior outcome compared to patients with intermediate WT1 expression. In the standard risk group of thymic T-lymphoblastic leukemia, aberrant WT1 expression was predictive for an inferior relapse-free survival as compared to patients with intermediate expression. In multivariate analysis, WT1 expression was of independent prognostic significance for relapse-free survival. CONCLUSIONS: WT1 mutations were associated with an inferior relapse-free survival in standard risk thymic T-lymphoblastic leukemia patients. Moreover, altered expression associated with inferior outcome also suggests a role of WT1 in T-lymphoblastic leukemia and the potential use of molecularly-based treatment stratification to improve outcome.

Prognostic implications of NOTCH1 and FBXW7 mutations in adult acute T-lymphoblastic leukemia.

BACKGROUND: NOTCH1 mutations have been associated with a favorable outcome in pediatric acute T-lymphoblastic leukemia. However, the results of studies on the prognostic significance of NOTCH1 mutations in adult T-lymphoblastic leukemia remain controversial. DESIGN AND METHODS: Here we have investigated the prognostic impact of mutations in the NOTCH1 pathway, in particular, the NOTCH1 and FBXW7 genes, in a large cohort of adult patients with T-lymphoblastic leukemia (n=126). We determined the occurrence of mutations in NOTCH1 and FBXW7 by DNA amplification and direct sequencing of polymerase chain reaction products. RESULTS: Mutations were identified in 57% and 12% of the NOTCH1 and FBXW7 genes, respectively. The characteristics of patients carrying NOTCH1 and/or FBXW7 (NOTCH1-FBXW7) mutations were similar to those with wild-type genes. Patients with NOTCH1-FBXW7 mutations more often showed a thymic immunophenotype (p=0.001). In the overall cohort, no significant differences were seen in the complete remission or event-free survival rates between patients with mutated or wild-type NOTCH1-FBXW7 (p=0.39). CONCLUSIONS: NOTCH1 and FBXW7 mutations were not predictive of outcome in the overall cohort of adult patients with T-lymphoblastic leukemia, but there was a trend towards a favorable prognostic impact of NOTCH1-FBXW7 mutations in the small subgroup of patients with low-risk ERG/BAALC expression status. Our findings further confirm the high frequency of NOTCH1 mutations in adult T-lymphoblastic leukemia.

AIDS-associated Burkitt or Burkitt-like lymphoma: short intensive polychemotherapy is feasible and effective.

The objective was to evaluate the feasibility and efficacy of a short-term, multi-agent and dose intensive regimen in AIDS patients with Burkitt or Burkitt-like lymphoma (BL/BLL) and to compare its efficacy with that of a conventional regimen. This was a retrospective, multi-center cohort study of all HIV-1-infected patients diagnosed with BL/BLL between 1990 - 2004. Patients were assigned to two different chemotherapy approaches. Group A received a protocol which was adapted from the German multi-center study group for adult acute lymphoblastic leukemia (GMALL). Group B received a conventional CHOP-based chemotherapy. Fifty-one patients were included in the analysis. In group A (n = 20), significantly more patients achieved complete remission (75% vs 40%, P = 0.02) than in group B (n = 31). One-year survival in group A was 65% compared to 44% in group B (P = 0.17). In a multi-variable Cox regression analysis, treatment according to the GMALL protocol was significantly associated with prolonged survival with a relative hazard rate of 0.13 (95% CI 0.03 - 0.63, P = 0.01). In conclusion, the short and intensive GMALL protocol for B-ALL/NHL is feasible in patients with AIDS-BL/BLL. Outcome may be improved compared to patients treated with CHOP-based regimens. In the era of HAART, more intensive chemotherapy regimens should be considered in patients with highly aggressive lymphomas.

MicroRNA profiling reveals aberrant microRNA expression in adult ETP-ALL and functional studies implicate a role for miR-222 in acute leukemia.

Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) has been identified as high-risk subgroup in acute T-cell lymphoblastic leukemia (T-ALL). To investigate the immature and myeloid nature of ETP-ALL we examined global microRNA (miRNA) expression in adult ETP-ALL. miRNA profiling of ETP-ALL (n=8), non-ETP T-ALL (n=6), and healthy controls was performed and results were validated in independent cohorts of 66 ETP-ALL and 111 non-ETP T-ALL using real-time RT-PCR. Furthermore, in vitro studies were performed on deregulated miRNAs in acute leukemia. We identified miR-221 and miR-222 as the most upregulated and six miRNAs (miR-151-3p, miR-19a, miR-20b, miR-342-3p, miR-363, and miR-576-3p) as downregulated in ETP-ALL compared to non-ETP T-ALL. In the validation cohorts, miR-221 and miR-222 were significantly upregulated in ETP-ALL, and miR-363 and miR-19a were downregulated in ETP-ALL. ETS1, downregulated in ETP-ALL, was identified as direct target of miR-222. In our in vitro studies miR-222 significantly inhibited proliferation, and caused cell cycle arrest and apoptosis in leukemic cells. In conclusion, our study revealed aberrant miRNA expression in ETP-ALL, with miR-221 and miR-222 as the most overexpressed miRNAs and implied a functional role for miR-222 in leukemic cells. Importantly, miR-222 may impact leukemogenesis by altering expression of the proto-oncogene ETS1 in acute leukemia.

L-asparaginase treatment in acute lymphoblastic leukemia: a focus on Erwinia asparaginase.

Asparaginases are a cornerstone of treatment protocols for acute lymphoblastic leukemia (ALL) and are used for remission induction and intensification treatment in all pediatric regimens and in the majority of adult treatment protocols. Extensive clinical data have shown that intensive asparaginase treatment improves clinical outcomes in childhood ALL. Three asparaginase preparations are available: the native asparaginase derived from Escherichia coli (E. coli asparaginase), a pegylated form of this enzyme (PEG-asparaginase), and a product isolated from Erwinia chrysanthemi, ie, Erwinia asparaginase. Clinical hypersensitivity reactions and silent inactivation due to antibodies against E. coli asparaginase, lead to inactivation of E. coli asparaginase in up to 60% of cases. Current treatment protocols include E. coli asparaginase or PEG-asparaginase for first-line treatment of ALL. Typically, patients exhibiting sensitivity to one formulation of asparaginase are switched to another to ensure they receive the most efficacious treatment regimen possible. Erwinia asparaginase is used as a second- or third-line treatment in European and US protocols. Despite the universal inclusion of asparaginase in such treatment protocols, debate on the optimal formulation and dosage of these agents continues. This article provides an overview of available evidence for optimal use of Erwinia asparaginase in the treatment of ALL.

Alternating versus concurrent schedules of imatinib and chemotherapy as front-line therapy for Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL).

The best strategy for incorporating imatinib in front-line treatment of Ph+ acute lymphoblastic leukemia (ALL) has not been established. We enrolled 92 patients with newly diagnosed Ph+ ALL in a prospective, multicenter study to investigate sequentially 2 treatment schedules with imatinib administered concurrent to or alternating with a uniform induction and consolidation regimen. Coadministration of imatinib and induction cycle 2 (INDII) resulted in a complete remission (CR) rate of 95% and polymerase chain reaction (PCR) negativity for BCR-ABL in 52% of patients, compared with 19% in patients in the alternating treatment cohort (P = .01). Remarkably, patients with and without a CR after induction cycle 1 (INDI) had similar hematologic and molecular responses after concurrent imatinib and INDII. In the concurrent cohort, grades III and IV cytopenias and transient hepatotoxicity necessitated interruption of induction in 87% and 53% of patients, respectively; however, duration of induction was not prolonged when compared with patients receiving chemotherapy alone. No imatinib-related severe hematologic or nonhematologic toxicities were noted with the alternating schedule. In each cohort, 77% of patients underwent allogeneic stem cell transplantation (SCT) in first CR (CR1). Both schedules of imatinib have acceptable toxicity and facilitate SCT in CR1 in the majority of patients, but concurrent administration of imatinib and chemotherapy has greater antileukemic efficacy.

CD10- pre-B acute lymphoblastic leukemia (ALL) is a distinct high-risk subgroup of adult ALL associated with a high frequency of MLL aberrations: results of the German Multicenter Trials for Adult ALL (GMALL).

Immunophenotyping disclosed CD10 negativity in 70 of 2408 cases of B-lineage acute lymphoblastic leukemia (ALL), although other criteria followed classification of pre-B ALL (eg, cytoplasmic immunoglobulin positivity). These blasts showed high myeloid antigen expression (60% CD65 positivity) and reacted with antibody 7.1 in 95% of the cases. MLL-AF4 fusion transcripts or an 11q23/MLL rearrangement or both were evident in 46 of 56 samples (82%). Although 83% of the patients achieved complete remission, the remission duration remained remarkably low: 141 days for MLL rearrangement-positive and 245 days for MLL rearrangement-negative CD10(-) pre-B ALL. Thus, the overall survival probability 3 years after diagnosis was 0.34 +/- 0.20 SE in MLL-rearrangement-negative versus 0.12 +/- 0.06 SE in MLL rearrangement-positive CD10- pre-B ALL. Our data identify CD10- cytoplasmic immunoglobulin-positive pre-B ALL as a rare (2.2%) but distinct immuno-subtype of adult ALL that is characterized by a high MLL rearrangement rate and a worse outcome.