Human endogenous retroviruses form a reservoir of T cell targets in hematological cancers

Human endogenous retroviruses (HERV) form a substantial part of the human genome, but mostly remain transcriptionally silent under strict epigenetic regulation, yet can potentially be reactivated by malignant transformation or epigenetic therapies. Here, we evaluate the potential for T cell recognition of HERV elements in myeloid malignancies by mapping transcribed HERV genes and generating a library of 1169 potential antigenic HERV-derived peptides predicted for presentation by 4 HLA class I molecules. Using DNA barcode-labeled MHC-I multimers, we find CD8+ T cell populations recognizing 29 HERV-derived peptides representing 18 different HERV loci, of which HERVH-5, HERVW-1, and HERVE-3 have more profound responses; such HERV-specific T cells are present in 17 of the 34 patients, but less frequently in healthy donors. Transcriptomic analyses reveal enhanced transcription of the HERVs in patients; meanwhile DNA-demethylating therapy causes a small and heterogeneous enhancement in HERV transcription without altering T cell recognition. Our study thus uncovers T cell recognition of HERVs in myeloid malignancies, thereby implicating HERVs as potential targets for immunotherapeutic therapies

Oral vitamin C supplementation to patients with myeloid cancer on azacitidine treatment: Normalization of plasma vitamin C induces epigenetic changes

Background Patients with haematological malignancies are often vitamin C deficient, and vitamin C is essential for the TET-induced conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), the first step in active DNA demethylation. Here, we investigate whether oral vitamin C supplementation can correct vitamin C deficiency and affect the 5hmC/5mC ratio in patients with myeloid cancers treated with DNA methyltransferase inhibitors (DNMTis). Results We conducted a randomized, double-blinded, placebo-controlled pilot trial (NCT02877277) in Danish patients with myeloid cancers performed during 3 cycles of DNMTi-treatment (5-azacytidine, 100 mg/m2/d for 5 days in 28-day cycles) supplemented by oral dose of 500 mg vitamin C (n = 10) or placebo (n = 10) daily during the last 2 cycles. Fourteen patients (70%) were deficient in plasma vitamin C (< 23 μM) and four of the remaining six patients were taking vitamin supplements at inclusion. Global DNA methylation was significantly higher in patients with severe vitamin C deficiency (< 11.4 μM; 4.997 vs 4.656% 5mC relative to deoxyguanosine, 95% CI [0.126, 0.556], P = 0.004). Oral supplementation restored plasma vitamin C levels to the normal range in all patients in the vitamin C arm (mean increase 34.85 ± 7.94 μM, P = 0.0004). We show for the first time that global 5hmC/5mC levels were significantly increased in mononuclear myeloid cells from patients receiving oral vitamin C compared to placebo (0.037% vs − 0.029%, 95% CI [− 0.129, − 0.003], P = 0.041). Conclusions Normalization of plasma vitamin C by oral supplementation leads to an increase in the 5hmC/5mC ratio compared to placebo-treated patients and may enhance the biological effects of DNMTis. The clinical efficacy of oral vitamin C supplementation to DNMTis should be investigated in a large randomized, placebo-controlled clinical trial

The Danish National Acute Leukemia Registry

Lene Sofie Granfeldt &Oslash;stg&aring;rd,1,2 Jan Maxwell N&oslash;rgaard,1 Klas Kr&aelig;sten Raaschou-Jensen,3 Robert Schou Pedersen,4 Dorthe R&oslash;nnov-Jessen,5 Per Troellund Pedersen,6 Inge H&oslash;gh Dufva,7 Claus Werenberg Marcher,8 Ove Juul Nielsen,9 Marianne Tang Severinsen,10,11 Lone Smidstrup Friis9 1Department of Hematology, 2Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, 3Department of Hematology, Copenhagen University Hospital, Roskilde, 4Department of Medicine, Holstebro Hospital, Holstebro, 5Department of Hematology, Vejle Hospital, Vejle, 6Department of Medicine, Esbjerg Hospital, Esbjerg, 7Department of Hematology, Copenhagen University Hospital, Herlev, 8Department of Hematology, Odense University Hospital, Odense, 9Department of Hematology, The National University Hospital, Rigshospitalet, Copenhagen, 10Department of Hematology, Aalborg University Hospital, Aalborg, Denmark, 11Department of Clinical Medicine, Aalborg University, Aalborg, Denmark Aim of database: The main aim of the Danish National Acute Leukemia Registry (DNLR) was to obtain information about the epidemiology of the hematologic cancers acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), and myelodysplastic syndrome (MDS). Study population: The registry was established in January 2000 by the Danish Acute Leukemia Group and has been expanded over the years. It includes adult AML patients diagnosed in Denmark since 2000, ALL patients diagnosed since 2005, and MDS patients diagnosed since 2010. The coverage of leukemia patients exceeds 99%, and the coverage of MDS patients is currently 90%. Main variables and descriptive data: Approximately, 250 AML patients, 25 ALL patients, and 230 MDS patients are registered in the DNLR every year. In January 2015, the registry included detailed patient characteristics, disease characteristics, treatment characteristics, and outcome data on more than 3,500 AML, 300 ALL, and 1,100 MDS patients. Many of the included prognostic variables have been found to be of high quality including positive predictive values and completeness exceeding 90%. These variables have been used in prognostic observational studies in the last few years. To ensure this high coverage, completeness, and quality of data, linkage to the Danish Civil Registration System and the Danish National Registry of Patients, and several programmed data entry checks are used. Conclusion: The completeness and positive predictive values of the leukemia data have been found to be high. In recent years, the DNLR has shown to be an important high-quality resource for clinical prognostic research. Keywords: data quality, registries, population-based, acute myeloid leukemia, acute lymphoblastic leukemia, myelodysplastic syndrom

Epidemiological study on survival of chronic myeloid leukemia (CML) and Ph+ acute lymphoblastic leukemia (ALL) patients with BCR-ABL T315I mutation.

The BCR-ABL T315I mutation represents a major mechanism of resistance to tyrosine kinase inhibitors (TKIs). The objectives of this retrospective observational study were to estimate overall and progression-free survival for chronic myeloid leukemia in chronic-phase (CP), accelerated-phase (AP), or blastic-phase (BP) and Philadelphia chromosome-positive (Ph)(+) acute lymphoblastic leukemia (ALL) patients with T315I mutation. Medical records of 222 patients from 9 countries were reviewed; data were analyzed using log-rank tests and Cox proportional hazard models. Median age at T315I mutation detection was 54 years; 57% cases were men. Median time between TKI treatment initiation and T315I mutation detection was 29.2, 15.4, 5.8, and 9.1 months, respectively, for CP, AP, BP, and Ph(+) ALL patients. After T315I mutation detection, second-generation TKIs were used in 56% of cases, hydroxyurea in 39%, imatinib in 35%, cytarabine in 26%, MK-0457 in 11%, stem cell transplantation in 17%, and interferon-alpha in 6% of cases. Median overall survival from T315I mutation detection was 22.4, 28.4, 4.0, and 4.9 months, and median progression-free survival was 11.5, 22.2, 1.8, and 2.5 months, respectively, for CP, AP, BP, and Ph(+) ALL patients. These results confirm that survival of patients harboring a T315I mutation is dependent on disease phase at the time of mutation detection