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The recent identification of rearrangements of neurotrophic tyrosine receptor kinase (NTRK) genes and the development of specific fusion protein inhibitors, such as larotrectinib and entrectinib, have revolutionised the diagnostic and clinical management of patients presenting with tumours with these alterations. Tumours that harbour NTRK fusions are found in both adults and children; and they are either rare tumours with common NTRK fusions that may be diagnostic, or more prevalent tumours with rare NTRK fusions. To assess currently available evidence on this matter, three key Spanish medical societies (the Spanish Society of Medical Oncology (SEOM), the Spanish Society of Pathological Anatomy (SEAP), and the Spanish Society of Paediatric Haematology and Oncology (SEHOP) have brought together a group of experts to develop a consensus document that includes guidelines on the diagnostic, clinical, and therapeutic aspects of NTRK-fusion tumours. This document also discusses the challenges related to the routine detection of these genetic alterations in a mostly public Health Care System., SEOM, SEAP and SEHOP have received financial support for this project in the form of unrestricted collaboration in the logistics of expert meeting from Bayer and Roche.

ALK inhibitors effectively target EML4-ALK positive non-small cell lung cancer, but their effects are hampered by treatment resistance. In the present study, we asked whether ALK inhibition affects autophagy, and whether this may influence treatment response. Whereas the impact of targeted therapies on autophagic activity previously have been assessed by surrogate marker proteins such as LC3B, we here thoroughly examined effects on functional autophagic activity, i.e. on the sequestration and degradation of autophagic cargo, in addition to autophagic markers. Interestingly, the ALK inhibitor Ceritinib decreased mTOR activity and increased GFP-WIPI1 dot formation in H3122 and H2228 EML4-ALK + lung cancer cells, suggesting autophagy activation. Moreover, an mCherry-EGFP-LC3B based assay indicated elevated LC3B carrier flux upon ALK inhibition. In accordance, autophagic cargo sequestration and long-lived protein degradation significantly increased upon ALK inhibition. Intriguingly, autophagic cargo flux was dependent on VPS34 and ULK1, but not LC3B. Co-treating H3122 cells with Ceritinib and a VPS34 inhibitor or Bafilomycin A1 resulted in reduced cell numbers. Moreover, VPS34 inhibition reduced clonogenic recovery of Ceritinib-treated cells. In summary, our results indicate that ALK inhibition triggers LC3B-independent macroautophagic flux in EML4-ALK + cells to support cancer cell survival and clonogenic growth.

Myeloproliferative neoplasms (MPN) show dysregulated JAK2 signaling. JAK2 inhibitors provide clinical benefits, but compensatory activation of MAPK pathway signaling impedes efficacy. We hypothesized that dual targeting of JAK2 and ERK1/2 could enhance clone control and therapeutic efficacy. We employed genetic and pharmacologic targeting of ERK1/2 in Jak2V617F MPN mice, cells and patient clinical isolates. Competitive transplantations of Jak2V617F vs. wild-type bone marrow (BM) showed that ERK1/2 deficiency in hematopoiesis mitigated MPN features and reduced the Jak2V617F clone in blood and hematopoietic progenitor compartments. ERK1/2 ablation combined with JAK2 inhibition suppressed MAPK transcriptional programs, normalized cytoses and promoted clone control suggesting dual JAK2/ERK1/2 targeting as enhanced corrective approach. Combined pharmacologic JAK2/ERK1/2 inhibition with ruxolitinib and ERK inhibitors reduced proliferation of Jak2V617F cells and corrected erythrocytosis and splenomegaly of Jak2V617F MPN mice. Longer-term treatment was able to induce clone reductions. BM fibrosis was significantly decreased in MPLW515L-driven MPN to an extent not seen with JAK2 inhibitor monotherapy. Colony formation from JAK2V617F patients’ CD34+ blood and BM was dose-dependently inhibited by combined JAK2/ERK1/2 inhibition in PV, ET, and MF subsets. Overall, we observed that dual targeting of JAK2 and ERK1/2 was able to enhance therapeutic efficacy suggesting a novel treatment approach for MPN.

Multiple myeloma (MM) is incurable, so there is a significant unmet need for effective therapy for patients with relapsed or refractory disease. This situation has not changed despite the recent approval of the anti-CD38 antibody daratumumab, one of the most potent agents in MM treatment. The efficiency of daratumumab might be improved by combining it with synergistic anti-MM agents. We therefore investigated the potential of the histone deacetylase (HDAC) inhibitor ricolinostat to up-regulate CD38 on MM cells, thereby enhancing the performance of CD38-specific therapies. Using quantitative reverse transcription polymerase chain reaction and flow cytometry, we observed that ricolinostat significantly increases CD38 RNA levels and CD38 surface expression on MM cells. Super-resolution microscopy imaging of MM cells by direct stochastic optical reconstruction microscopy confirmed this rise with molecular resolution and revealed homogeneous distribution of CD38 molecules on the cell membrane. Particularly important is that combining ricolinostat with daratumumab induced enhanced lysis of MM cells. We also evaluated next-generation HDAC6 inhibitors (ACY-241, WT-161) and observed similar increase of CD38 levels suggesting that the upregulation of CD38 expression on MM cells by HDAC6 inhibitors is a class effect. This proof-of-concept illustrates the potential benefit of combining HDAC6 inhibitors and CD38-directed immunotherapy for MM treatment., This work was supported by the project “Center for Personalized Molecular Immunotherapy” funded within the EFRE-program of the European Union (Europäischer Fond für regionale Entwicklung); a grant from the German Ministry for Science and Education (BMBF, Bundesministerium für Bildung und Forschung, Grant # 13N14414). EG-G was supported by Instituto de Salud Carlos III (PFIS—FI12/00189). S Danhof was supported by the IZKF Würzburg (Interdisziplinäres Zentrum für Klinische Forschung), the MSNZ Würzburg (Mildred-Scheel-Nachwuchszentrum), and was a fellow of the Clinician Scientist Program of the Else-Kröner Forschungskolleg. MH was supported by Young Scholar Program of the Bavarian Academy of Sciences (Junges Kolleg, Bayerische Akademie der Wissenschaften).

Diffuse intrinsic pontine glioma (DIPG) is a lethal childhood brainstem tumour, with a quarter of patients harbouring somatic mutations in ACVR1, encoding the serine/threonine kinase ALK2. Despite being an amenable drug target, little has been done to-date to systematically evaluate the role of ACVR1 in DIPG, nor to screen currently available inhibitors in patient-derived tumour models. Here we show the dependence of DIPG cells on the mutant receptor, and the preclinical efficacy of two distinct chemotypes of ALK2 inhibitor in vitro and in vivo. We demonstrate the pyrazolo[1,5-a]pyrimidine LDN-193189 and the pyridine LDN-214117 to be orally bioavailable and well-tolerated, with good brain penetration. Treatment of immunodeprived mice bearing orthotopic xenografts of H3.3K27M, ACVR1R206H mutant HSJD-DIPG-007 cells with 25 mg/kg LDN-193189 or LDN-214117 for 28 days extended survival compared with vehicle controls. Development of ALK2 inhibitors with improved potency, selectivity and advantageous pharmacokinetic properties may play an important role in therapy for DIPG patients., Diana Carvalho, Kathryn R. Taylor et al. show that ALK2 inhibitors induce apoptosis of ACVR1 mutant diffuse intrinsic pontine glioma cells in vitro. These compounds also increase the survival of mice carrying ACVR1 mutant brainstem xenografts, suggesting ALK2 as a potential pharmacological target against this lethal cancer.

The purpose was to assess predictive factors for outcome in patients with chronic myeloid leukemia (CML) in chronic phase (CML-CP) treated with nilotinib after imatinib failure. Imatinib-resistant and -intolerant patients with CML-CP (n = 321) were treated with nilotinib 400 mg twice daily. Of 19 baseline patient and disease characteristics and two response end points analyzed, 10 independent prognostic factors were associated with progression-free survival (PFS). In the multivariate analysis, major cytogenetic response (MCyR) within 12 months, baseline hemoglobin >= 120 g/l, baseline basophils

The impact of proton pump inhibitors (PPIs) and histamine H2 receptor antagonists (H2 blockers) on the efficacy of nilotinib was evaluated. Retrospective analyses were performed in patients with newly diagnosed Philadelphia chromosome-positive (Ph+) chronic myeloid leukemia in chronic phase (CML-CP; N = 492) and in patients with imatinib-resistant or imatinib-intolerant Ph+ CML-CP (N = 256) treated with nilotinib. In the newly diagnosed population, 87 (17.7 %) and 49 (10.0 %) patients received PPIs and H2 blockers, respectively. Major molecular response at 12 months was achieved by 59 (49.6 %) patients who received at least one PPI or H2 blocker (n = 119) and 153 (41.0 %) patients who did not receive any comedication (n = 373; P = 0.13). PPIs and H2 blockers were used by 77 (30.1 %) and 17 (6.6 %) patients with imatinib-resistant or imatinib-intolerant CML-CP, respectively. Major cytogenetic response by 12 months was achieved by 55 (64.0 %) patients who received at least one PPI or H2 blocker (n = 86) versus 98 (57.6 %) patients who did not receive any comedication (n = 170; P = 0.40); 39 (45.3 %) versus 65 (38.2 %), respectively, achieved complete cytogenetic response by 12 months (P = 0.34). Similar findings were observed in patients who received comedication for > 50 % of the time on nilotinib therapy. Nilotinib steady-state trough concentration was not affected by the presence of PPIs or H2 blockers. Concurrent use of PPIs or H2 blockers did not affect the pharmacokinetics and efficacy of nilotinib in patients with Ph+ CML-CP.