Anti-ALK Antibodies in Patients with ALK-Positive Malignancies Not Expressing NPM-ALK.

Patients with Nucleophosmin (NPM)- Anaplastic Lymphoma Kinase (ALK) fusion positive Anaplastic Large Cell Lymphoma produce autoantibodies against ALK indicative of an immune response against epitopes of the chimeric fusion protein. We asked whether ALK-expression in other malignancies induces specific antibodies. Antibodies against ALK were detected in sera of one of 50 analysed ALK-expressing neuroblastoma patients, 13 of 21 ALK positive non-small cell lung carcinoma (NSCLC) patients, 13 of 22 ALK translocation-positive, but NPM-ALK-negative lymphoma patients and one of one ALK-positive rhabdomyosarcoma patient, but not in 20 healthy adults. These data suggest that boosting a pre-existent anti-ALK immune response may be more feasible for patients with ALK-positive NSCLC, lymphomas and rhabdomyosarcomas than for tumours expressing wild-type ALK.This work was supported by a grant from the Deutsche Jose Carreras Leukämie-Stiftung (DJCLS08/ 09) to WW, and RS. CDW and WW are additionally supported by the von behring röntgen stiftung (60-0011) and the Forschungshilfe Peiper, IO and RS by the Kinderkrebsinitiative Buchholz/HolmSeppensen and KP by Bloodwise, the Julian Starmer-Smith Memorial Fund and the Sam Foye Fund. SDT is a Bloodwise University Senior Lecturer and is also supported by the Alex Hulme Foundation and the Sam Foye Fund. MH is supported by a PhD studentship from the Wellcome Trust.This is the final version of the article. It first appeared from Ivyspring International via http://dx.doi.org/10.7150/jca.1523

Inhibition of Anaplastic Lymphoma Kinase (ALK) Activity Provides a Therapeutic Approach for CLTC-ALK-Positive Human Diffuse Large B Cell Lymphomas

ALK positive diffuse large B-cell lymphomas (DLBCL) are a distinct lymphoma subtype associated with a poor outcome. Most of them feature a t(2;17) encoding a clathrin (CLTC)-ALK fusion protein. The contribution of deregulated ALK-activity in the pathogenesis and maintenance of these DLBCLs is not yet known. We established and characterized the first CLTC-ALK positive DLBCL cell line (LM1). LM1 formed tumors in NOD-SCID mice. The selective ALK inhibitor NVP-TAE684 inhibited growth of LM1 cells in vitro at nanomolar concentrations. NVP-TAE684 repressed ALK-activated signalling pathways and induced apoptosis of LM1 DLBCL cells. Inhibition of ALK-activity resulted in sustained tumor regression in the xenotransplant tumor model. These data indicate a role of CLTC-ALK in the maintenance of the malignant phenotype thereby providing a rationale therapeutic target for these otherwise refractory tumors

Non-Hodgkin Lymphoma in Children and Adolescents: Progress Through Effective Collaboration, Current Knowledge, and Challenges Ahead

Non-Hodgkin lymphoma is the fourth most common malignancy in children, has an even higher incidence in adolescents, and is primarily represented by only a few histologic subtypes. Dramatic progress has been achieved, with survival rates exceeding 80%, in large part because of a better understanding of the biology of the different subtypes and national and international collaborations. Most patients with Burkitt lymphoma and diffuse large B-cell lymphoma are cured with short intensive pulse chemotherapy containing cyclophosphamide, cytarabine, and high-dose methotrexate. The benefit of the addition of rituximab has not been established except in the case of primary mediastinal B-cell lymphoma. Lymphoblastic lymphoma is treated with intensive, semi-continuous, longer leukemia-derived protocols. Relapses in B-cell and lymphoblastic lymphomas are rare and infrequently curable, even with intensive approaches. Event-free survival rates of approximately 75% have been achieved in anaplastic large-cell lymphomas with various regimens that generally include a short intensive B-like regimen. Immunity seems to play an important role in prognosis and needs further exploration to determine its therapeutic application. ALK inhibitor therapeutic approaches are currently under investigation. For all pediatric lymphomas, the intensity of induction/consolidation therapy correlates with acute toxicities, but because of low cumulative doses of anthracyclines and alkylating agents, minimal or no long-term toxicity is expected. Challenges that remain include defining the value of prognostic factors, such as early response on positron emission tomography/computed tomography and minimal disseminated and residual disease, using new biologic technologies to improve risk stratification, and developing innovative therapies, both in the first-line setting and for relapse

Anaplastic large cell lymphoma in paediatric and young adult patients.

Anaplastic large cell lymphoma (ALCL) is a heterogeneous disease of debateable origin that, in children, is largely anaplastic lymphoma kinase (ALK) positive with aberrant ALK activity induced following the formation of chromosomal translocations. Whilst the survival rates for this disease are relatively high, a significant proportion (20-40%) of patients suffer disease relapse, in some cases on multiple occasions and therefore suffer the toxic side-effects of combination chemotherapy. Traditionally, patients are treated with a combination of agents although recent data from relapse patients have suggested that low risk patients might benefit from single agent vinblastine and, going forward, the addition of ALK inhibitors to the therapeutic regimen may have beneficial consequences. There are also a plethora of other drugs that might be advantageous to patients with ALCL and many of these have been identified through laboratory research although the decision as to which drugs to implement in trials will not be trivial.Supported in part by the Pediatric Cancer Research Foundation and Fondazione Giacomo Ascoli. S.D.T. is supported with funding from BloodwiseThis is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1111/bjh.1395

Prognostic Factors in Childhood Anaplastic Large Cell Lymphoma: Long Term Results of the International ALCL99 Trial

With the aim of describing the long-term follow-up and to define the prognostic role of the clinical/pathological/molecular characteristics at diagnosis for childhood, adolescent and young adults affected by anaplastic large cell lymphoma (ALCL), we analyzed 420 patients aged up to 22 years homogeneously treated within the international ALCL99 trial. The 10-year progression free survival (PFS) was 70% and overall survival was 90%, rare late relapses occurred but no secondary malignancies were reported. Among clinical/pathological characteristics, only patients presenting a small cell/lymphohistiocytic (SC/LH) pattern were independently associated with risk of failure (hazard ratio = 2.49). Analysis of minimal disseminated disease (MDD), available for 162 patients, showed that both SC/LH pattern (hazard ratio = 2.4) and MDD positivity (hazard ratio = 2.15) were significantly associated with risk of failure in multivariate analysis. Considering MDD and SC/LH results, patients were separated into three biological/pathological (bp) risk groups: a high-risk group (bpHR) including MDD-positive patients with SC/LH pattern; a low-risk group (bpLR) including MDD-negative patients without SC/LH pattern; and an intermediate-risk group (bpIR) including remaining patients. The 10-year PFS was 40%, 75% and 86% for bpHR, bpIR and bpLR, respectively (p 0.0001). These results should be considered in the design of future ALCL trials to tailor individual treatments

The AP-1-BATF and -BATF3 module is essential for growth, survival and TH17/ILC3 skewing of anaplastic large cell lymphoma.

Transcription factor AP-1 is constitutively activated and IRF4 drives growth and survival in ALK+ and ALK- anaplastic large cell lymphoma (ALCL). Here we demonstrate high-level BATF and BATF3 expression in ALCL. Both BATFs bind classical AP-1 motifs and interact with in ALCL deregulated AP-1 factors. Together with IRF4, they co-occupy AP-1-IRF composite elements, differentiating ALCL from non-ALCL. Gene-specific inactivation of BATFs, or global AP-1 inhibition results in ALCL growth retardation and/or cell death in vitro and in vivo. Furthermore, the AP-1-BATF module establishes TH17/group 3 innate lymphoid cells (ILC3)-associated gene expression in ALCL cells, including marker genes such as AHR, IL17F, IL22, IL26, IL23R and RORγt. Elevated IL-17A and IL-17F levels were detected in a subset of children and adolescents with ALK+ ALCL. Furthermore, a comprehensive analysis of primary lymphoma data confirms TH17-, and in particular ILC3-skewing in ALCL compared with PTCL. Finally, pharmacological inhibition of RORC as single treatment leads to cell death in ALCL cell lines and, in combination with the ALK inhibitor crizotinib, enforces death induction in ALK+ ALCL. Our data highlight the crucial role of AP-1/BATFs in ALCL and lead to the concept that some ALCL might originate from ILC3

Super-enhancer-based identification of a BATF3/IL-2R-module reveals vulnerabilities in anaplastic large cell lymphoma.

Anaplastic large cell lymphoma (ALCL), an aggressive CD30-positive T-cell lymphoma, comprises systemic anaplastic lymphoma kinase (ALK)-positive, and ALK-negative, primary cutaneous and breast implant-associated ALCL. Prognosis of some ALCL subgroups is still unsatisfactory, and already in second line effective treatment options are lacking. To identify genes defining ALCL cell state and dependencies, we here characterize super-enhancer regions by genome-wide H3K27ac ChIP-seq. In addition to known ALCL key regulators, the AP-1-member BATF3 and IL-2 receptor (IL2R)-components are among the top hits. Specific and high-level IL2R expression in ALCL correlates with BATF3 expression. Confirming a regulatory link, IL-2R-expression decreases following BATF3 knockout, and BATF3 is recruited to IL2R regulatory regions. Functionally, IL-2, IL-15 and Neo-2/15, a hyper-stable IL-2/IL-15 mimic, accelerate ALCL growth and activate STAT1, STAT5 and ERK1/2. In line, strong IL-2Rα-expression in ALCL patients is linked to more aggressive clinical presentation. Finally, an IL-2Rα-targeting antibody-drug conjugate efficiently kills ALCL cells in vitro and in vivo. Our results highlight the importance of the BATF3/IL-2R-module for ALCL biology and identify IL-2Rα-targeting as a promising treatment strategy for ALCL

Standardisation and consensus guidelines for minimal residual disease assessment in Philadelphia-positive acute lymphoblastic leukemia (Ph?+?ALL) by real-time quantitative reverse transcriptase PCR of e1a2 BCR-ABL1

Minimal residual disease (MRD) is a powerful prognostic factor in acute lymphoblastic leukemia (ALL) and is used for patient stratification and treatment decisions, but its precise role in Philadelphia chromosome positive ALL is less clear. This uncertainty results largely from methodological differences relating to the use of real-time quantitative PCR (qRT-PCR) to measure BCR-ABL1 transcript levels for MRD analysis. We here describe the first results by the EURO-MRD consortium on standardization of qRT-PCR for the e1a2 BCR-ABL1 transcript in Ph + ALL, designed to overcome the lack of standardisation of laboratory procedures and data interpretation. Standardised use of EAC primer/probe sets and of centrally prepared plasmid standards had the greatest impact on reducing interlaboratory variability. In QC1 the proportion of analyses with BCR-ABL1/ABL1 ratios within half a log difference were 40/67 (60%) and 52/67 (78%) at 10−3 and 36/67 (53%) and 53/67 (79%) at 10−4BCR-ABL1/ABL1. Standardized RNA extraction, cDNA synthesis and cycler platforms did not improve results further, whereas stringent application of technical criteria for assay quality and uniform criteria for data interpretation and reporting were essential. We provide detailed laboratory recommendations for the standardized MRD analysis in routine diagnostic settings and in multicenter clinical trials for Ph + ALL

Pediatric T- and NK-cell lymphomas: new biologic insights and treatment strategies

T- and natural killer (NK)-cell lymphomas are challenging childhood neoplasms. These cancers have varying presentations, vast molecular heterogeneity, and several are quite unusual in the West, creating diagnostic challenges. Over 20 distinct T- and NK-cell neoplasms are recognized by the 2008 World Health Organization classification, demonstrating the diversity and potential complexity of these cases. In pediatric populations, selection of optimal therapy poses an additional quandary, as most of these malignancies have not been studied in large randomized clinical trials. Despite their rarity, exciting molecular discoveries are yielding insights into these clinicopathologic entities, improving the accuracy of our diagnoses of these cancers, and expanding our ability to effectively treat them, including the use of new targeted therapies. Here, we summarize this fascinating group of lymphomas, with particular attention to the three most common subtypes: T-lymphoblastic lymphoma, anaplastic large cell lymphoma, and peripheral T-cell lymphoma-not otherwise specified. We highlight recent findings regarding their molecular etiologies, new biologic markers, and cutting-edge therapeutic strategies applied to this intriguing class of neoplasms

Prognostic factors in paediatric anaplastic large cell lymphoma: role of ALK

Event-free survival of children and adolescents with ALK-positive anaplastic large cell lymphoma (ALCL) reaches 65-75% with current chemotherapy regimen. Risk stratification of children with ALCL was, until now, based on clinical parameters. More recently, pathological and biological risk factors have been described in trials applying BFM-type chemotherapy. Histological subtypes containing small-cell or lymphohistiocytic components indicate a high risk of failure. Minimal disseminated disease (MDD) detected by qualitative RT-PCR for NPM-ALK in bone marrow or blood is associated with a relapse risk of 50%. Quantification of MDD and persistent minimal residual disease (MRD) characterize very high risk patients. Serum ALK-autoantibody titres inversely correlate with relapse risk. The combination of MDD and ALK-antibody titre separates both low and very high risk patients from those with standard risk. In relapse, the time of relapse/progression, central nervous system and bone marrow involvement are major risk factors. In conclusion, MDD, MRD, ALK-antibody titres and histological subtype are strong biological risk factors in childhood ALCL. The combination of MDD and ALK-antibody titre may serve for patient stratification in upcoming clinical trials