Identification of physiologically relevant peptide vaccine targets calls for the direct analysis of the entirety of naturally presented human leukocyte antigen (HLA) ligands, termed the HLA ...ligandome. In this study, we implemented this direct approach using immunoprecipitation and mass spectrometry to define acute myeloid leukemia (AML)-associated peptide vaccine targets. Mapping the HLA class I ligandomes of 15 AML patients and 35 healthy controls, more than 25 000 different naturally presented HLA ligands were identified. Target prioritization based on AML exclusivity and high presentation frequency in the AML cohort identified a panel of 132 LiTAAs (ligandome-derived tumor-associated antigens), and 341 corresponding HLA ligands (LiTAPs (ligandome-derived tumor-associated peptides)) represented subset independently in >20% of AML patients. Functional characterization of LiTAPs by interferon-γ ELISPOT (Enzyme-Linked ImmunoSpot) and intracellular cytokine staining confirmed AML-specific CD8(+) T-cell recognition. Of note, our platform identified HLA ligands representing several established AML-associated antigens (e.g. NPM1, MAGED1, PRTN3, MPO, WT1), but found 80% of them to be also represented in healthy control samples. Mapping of HLA class II ligandomes provided additional CD4(+) T-cell epitopes and potentially synergistic embedded HLA ligands, allowing for complementation of a multipeptide vaccine for the immunotherapy of AML.
Preliminary evidence suggests that the multikinase inhibitor sorafenib has clinical activity in FLT3-ITD-positive (FLT3-ITD) acute myeloid leukemia (AML). However, the quality and sustainability of ...achievable remissions and clinical variables that influence the outcome of sorafenib monotherapy are largely undefined. To address these questions, we evaluated sorafenib monotherapy in 65 FLT3-ITD AML patients treated at 23 centers. All but two patients had relapsed or were chemotherapy-refractory after a median of three prior chemotherapy cycles. Twenty-nine patients (45%) had undergone prior allogeneic stem cell transplantation (allo-SCT). The documented best responses were: hematological remission in 24 patients (37%), bone marrow remission in 5 patients (8%), complete remission (with and without normalization of peripheral blood counts) in 15 patients (23%) and molecular remission with undetectable FLT3-ITD mRNA in 10 patients (15%), respectively. Seventeen of the patients without prior allo-SCT (47%) developed sorafenib resistance after a median treatment duration of 136 days (range, 56-270 days). In contrast, allo-SCT patients developed sorafenib resistance less frequently (38%) and significantly later (197 days, range 38-225 days; P=0.03). Sustained remissions were seen exclusively in the allo-SCT cohort. Thus, sorafenib monotherapy has significant activity in FLT3-ITD AML and may synergize with allogeneic immune effects to induce durable remissions.
Abstract
The aim of this randomized clinical trial was to evaluate the impact of all-
trans
retinoic acid (ATRA) in combination with non-intensive chemotherapy in older unfit patients (> 60 years) ...with newly diagnosed
NPM1
-mutated acute myeloid leukemia. Patients were randomized (1:1) to low-dose chemotherapy with or without open-label ATRA 45 mg/m
2
, days 8–28; the dose of ATRA was reduced to 45 mg/m
2
, days 8–10 and 15 mg/m
2
, days 11–28 after 75 patients due to toxicity. Up to 6 cycles of cytarabine 20 mg/day s.c., bid, days 1–7 and etoposide 100 mg/day, p.o. or i.v., days 1–3 with (ATRA) or without ATRA (CONTROL) were intended. The primary endpoint was overall survival (OS). Between May 2011 and September 2016, 144 patients (median age, 77 years; range, 64–92 years) were randomized (72, CONTROL; 72, ATRA). Baseline characteristics were balanced between the two study arms. The median number of treatment cycles was 2 in ATRA and 2.5 in CONTROL. OS was significantly shorter in the ATRA compared to the CONTROL arm (
p
= 0.023; median OS: 5 months versus 9.2 months, 2-years OS rate: 7% versus 10%, respectively). Rates of CR/CRi were not different between treatment arms; infections were more common in ATRA beyond treatment cycle one. The addition of ATRA to low-dose cytarabine plus etoposide in an older, unfit patient population was not beneficial, but rather led to an inferior outcome.
The clinical trial is registered at clinicaltrialsregister.eu (EudraCT Number: 2010-023409-37, first posted 14/12/2010).
Fms-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD)–positive acute myeloid leukaemia (AML) relapsing after allogeneic stem cell transplantation (allo-SCT) has a dismal prognosis with ...limited therapeutic options. FLT3-ITD kinase inhibition is a reasonable but palliative experimental treatment alternative in this situation. Information on long-term outcome is not available.
We performed a long-term follow-up analysis of a previously reported cohort of 29 FLT3-ITD–positive AML patients, which were treated in relapse after allo-SCT with sorafenib monotherapy.
With a median follow-up of 7.5 years, 6 of 29 patients (21%) are still alive. Excluding one patient who received a second allo-SCT, five patients (17%) achieved sustained complete remissions with sorafenib. Four of these patients are in treatment-free remission for a median of 4.4 years.
Sorafenib may enable cure of a proportion of very poor risk FLT3-ITD–positive AML relapsing after allo-SCT.
•Sorafenib induces long-term survival in Fms-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD)+ acute myeloid leukaemia (AML) relapsing after allogeneic stem cell transplantation (allo-SCT).•Sorafenib cures a minority of FLT3-ITD+ AML relapsing after allo-SCT.•Achievement of molecular negativity is strongly associated with cure.
The fms-related tyrosine kinase 3 (FLT3) receptor has been extensively studied over the past two decades with regard to oncogenic alterations that do not only serve as prognostic markers but also as ...therapeutic targets in acute myeloid leukemia (AML). Internal tandem duplications (ITDs) became of special interest in this setting as they are associated with unfavorable prognosis. Because of sequence-dependent protein conformational changes FLT3-ITD tends to autophosphorylate and displays a constitutive intracellular localization. Here, we analyzed the effect of tyrosine kinase inhibitors (TKIs) on the localization of the FLT3 receptor and its mutants. TKI treatment increased the surface expression through upregulation of FLT3 and glycosylation of FLT3-ITD and FLT3-D835Y mutants. In T cell-mediated cytotoxicity (TCMC) assays, using a bispecific FLT3 × CD3 antibody construct, the combination with TKI treatment increased TCMC in the FLT3-ITD-positive AML cell lines MOLM-13 and MV4-11, patient-derived xenograft cells and primary patient samples. Our findings provide the basis for rational combination of TKI and FLT3-directed immunotherapy with potential benefit for FLT3-ITD-positive AML patients.
All-trans retinoic acid (ATRA) with chemotherapy is the standard of care for acute promyelocytic leukemia (APL), resulting in cure rates exceeding 80%. Pilot studies of treatment with arsenic ...trioxide with or without ATRA have shown high efficacy and reduced hematologic toxicity.
We conducted a phase 3, multicenter trial comparing ATRA plus chemotherapy with ATRA plus arsenic trioxide in patients with APL classified as low-to-intermediate risk (white-cell count, ≤10×10(9) per liter). Patients were randomly assigned to receive either ATRA plus arsenic trioxide for induction and consolidation therapy or standard ATRA-idarubicin induction therapy followed by three cycles of consolidation therapy with ATRA plus chemotherapy and maintenance therapy with low-dose chemotherapy and ATRA. The study was designed as a noninferiority trial to show that the difference between the rates of event-free survival at 2 years in the two groups was not greater than 5%.
Complete remission was achieved in all 77 patients in the ATRA-arsenic trioxide group who could be evaluated (100%) and in 75 of 79 patients in the ATRA-chemotherapy group (95%) (P=0.12). The median follow-up was 34.4 months. Two-year event-free survival rates were 97% in the ATRA-arsenic trioxide group and 86% in the ATRA-chemotherapy group (95% confidence interval for the difference, 2 to 22 percentage points; P<0.001 for noninferiority and P=0.02 for superiority of ATRA-arsenic trioxide). Overall survival was also better with ATRA-arsenic trioxide (P=0.02). As compared with ATRA-chemotherapy, ATRA-arsenic trioxide was associated with less hematologic toxicity and fewer infections but with more hepatic toxicity.
ATRA plus arsenic trioxide is at least not inferior and may be superior to ATRA plus chemotherapy in the treatment of patients with low-to-intermediate-risk APL. (Funded by Associazione Italiana contro le Leucemie and others; ClinicalTrials.gov number, NCT00482833.).
•Endobronchial teratoma is an extremely rare disease.•Presentation could mimic bronchogenic cancer.•Lobectomy or pneumonectomy is the treatment of choice.•A brief review with a new case has been ...discussed.
Endobronchial teratoma is sporadic disease. The study aims to present a case with endobronchial teratoma with a brief literature review. A 26-year-old male presented with a history of frequent attacks of chest infection for the last two years. Chest examination showed diffuse wheeze all over the left side of the chest. Chest x.ray showed opacification involving all of the left side of the chest with elevated left hemi diaphragm while computed tomography scan confirmed complete collapse of the left lung with consolidations and air bronchogram. Flexible bronchoscopy showed near-total obstruction of the left main bronchus. Under general anesthesia, left pneumonectomy was performed. The result of the histopathological examinataion showed mature teratoma.
Endobronchial teratoma is an exceedingly rare type of intrathoracic teratoma that mainly affects males and is usually diagnosed at the 3rd decade of life; lobectomy or pneumonectomy are optimal managements for these cases.
Natural killer (NK) cells play an important role in the immunosurveillance of hematopoietic malignancies. Their reactivity is influenced by activating and inhibitory signals mediated by ...tumor-expressed ligands for NK receptors. Many members of the tumor necrosis factor (TNF) family modulate differentiation, proliferation, activation and death of both tumor and immune effector cells. The TNF receptor family member glucocorticoid-induced TNFR-related protein (GITR) stimulates anti-tumor immunity in mice, but available data indicate that GITR may mediate different effects in mice and men and impairs the reactivity of human NK cells. Here, we comprehensively studied the expression and function of GITR ligand (GITRL) in leukemia. Among the different leukemia entities, pronounced expression of GITRL on leukemic cells was observed in chronic lymphocytic leukemia (CLL), and the GITR receptor was expressed at significantly higher levels on NK cells of CLL patients compared with healthy controls. Upon GITR-GITRL interaction, signaling via GITRL into the leukemia cells induced the release of interleukin (IL)-6, IL-8 and TNF, which act as growth and survival factors for CLL cells. In addition, GITRL impaired both direct and Rituximab-induced degranulation, cytotoxicity and interferon-γ production of NK cells, which could be restored by GITR blocking antibodies. Thus, GITRL may contribute to disease pathophysiology and resistance to direct and Rituximab-induced NK reactivity in CLL.
In chronic myeloid leukemia (CML), BCR-ABL-mediated oncogenic signaling can be successfully targeted with the BCRABL- inhibitors imatinib, nilotinib, and dasatinib leading to complete cytogenetic ...(Philadelphia chromosome not detectable upon cytogenetic testing of bone marrow) and even complete molecular (BCR-ABL not detectable by PCR in peripheral blood) responses. However, CML apparently can not be cured by BCR-ABL inhibitors alone, likely due to treatment-resistance of CML stem/progenitor cells, which provokes a relapse of disease after cessation of therapy. Evidence from patients treated with allogenic stem cell transplantation or IFN-α points to an important role of anti-tumor immunity for durable control of CML disease. Data from multiple in vitro and ex vivo studies indicate that BCR-ABL inhibitors may also influence anti-tumor immunity. Varying effects on different immune effector cell subsets and of the different compounds have been reported, the latter being due to their particular and diverse potency and spectrum of target kinases. As multiple approaches presently aim to combine BCR-ABL inhibition with immunotherapeutic strategies to improve disease control in CML, immunomodulatory effects of the available BCR-ABL inhibitors may be of direct clinical relevance. Here we review the available data regarding the effects of imatinib, nilotinib, and dasatinib on dendritic cells, T cells and natural killer cells as important cellular components of anti-tumor immunity.