Prognostic gene alterations and clonal changes in childhood B-ALL
LEUKEMIA RESEARCH
Authors: Erbilgin, Yucel; Firtina, Sinem; Mercan, Sevcan; Ng, Ozden Hatirnaz; Karaman, Serap; Tasar, Orcun; Karakas, Zeynep; Celkan, Tulin Tiraje; Zenging, Emine; Sarperg, Nazan; Yildirmak, Zeynep Yildiz; Sisko, Sinem; Ozbek, Ugur; Sayitoglu, Muge
Abstract
Genomic profiles of leukemia patients lead to characterization of variations that provide the molecular classification of risk groups, prediction of clinical outcome and therapeutic decisions. In this study, we examined the diagnostic (n = 77) and relapsed (n = 31) pediatric B-cell acute lymphoblastic leukemia (B-ALL) samples for the most common leukemia-associated gene variations CRLF2, JAK2, PAX5 and IL7R using deep sequencing and copy number alterations (CNAs) (CDKN2A/2B, PAX5, RB1, BTG1, ETV6, CSF2RA, IL3RA and CRLF2) by multiplex ligation proximity assay (MLPA), and evaluated for the clonal changes through relapse. Single nucleotide variations SNVs were detected in 19% of diagnostic 15.3% of relapse samples. The CNAs were detected in 55% of diagnosed patients; most common affected genes were CDKN2A/2B, PAX5, and CRLF2. Relapse samples did not accumulate a greater number of CNAs or SNVs than the cohort of diagnostic samples, but the clonal dynamics showed the accumulation/disappearance of specific gene variations explained the course of relapse. The CDKN2A/2B were most frequently altered in relapse samples and 32% of relapse samples carried at least one CNA. Moreover, CDKN2A/2B alterations and/or JAK2 variations were associated with decreased relapse-free survival. On the other hand, CRLF2 copy number alterations predicted a better survival rate in B-ALL. These findings contribute to the knowledge of CDKN2A/2B and CRLF2 alterations and their prognostic value in B-ALL. The integration of genomic data in clinical practice will enable better stratification of ALL patients and allow deeper understanding of the nature of relapse.
Tagraxofusp in Blastic Plasmacytoid Dendritic-Cell Neoplasm
NEW ENGLAND JOURNAL OF MEDICINE
Authors: Pemmaraju, Naveen; Lane, Andrew A.; Sweet, Kendra L.; Stein, Anthony S.; Vasu, Sumithira; Blum, William; Rizzieri, David A.; Wang, Eunice S.; Duvic, Madeleine; Sloan, J. Mark; Spence, Sharon; Shemesh, Shay; Brooks, Christopher L.; Balser, John; Bergstein, Ivan; Lancet, Jeffrey E.; Kantarjian, Hagop M.; Konopleva, Marina
Abstract
Background Blastic plasmacytoid dendritic-cell neoplasm (BPDCN) is an aggressive hematologic cancer that is caused by transformed plasmacytoid dendritic cells that overexpress interleukin-3 receptor subunit alpha (IL3RA or CD123). Tagraxofusp (SL-401) is a CD123-directed cytotoxin consisting of human interleukin-3 fused to truncated diphtheria toxin. Methods In this open-label, multicohort study, we assigned 47 patients with untreated or relapsed BPDCN to receive an intravenous infusion of tagraxofusp at a dose of 7 mu g or 12 mu g per kilogram of body weight on days 1 to 5 of each 21-day cycle. Treatment continued until disease progression or unacceptable toxic effects. The primary outcome was the combined rate of complete response and clinical complete response among patients who had not received previous treatment for BPDCN. A secondary outcome was the duration of response. Results Of the 47 patients, 32 were receiving tagraxofusp as first-line treatment and 15 had received previous treatment. The median age of the patients was 70 years (range, 22 to 84). Among the 29 previously untreated patients who received tagraxofusp at a dose of 12 mu g per kilogram, the primary outcome occurred in 21 (72%), and the overall response rate was 90%; of these patients, 45% went on to undergo stem-cell transplantation. Survival rates at 18 and 24 months were 59% and 52%, respectively. Among the 15 previously treated patients, the response rate was 67%, and the median overall survival was 8.5 months. The most common adverse events were increased levels of alanine aminotransferase (64%) and aspartate aminotransferase (60%), hypoalbuminemia (55%), peripheral edema (51%), and thrombocytopenia (49%). Capillary leak syndrome was reported in 19% of the patients and was associated with one death in each of the dose subgroups. Conclusions In adult patients with untreated or relapsed BPDCN, the use of tagraxofusp led to clinical responses. Serious adverse events included capillary leak syndrome; hepatic dysfunction and thrombocytopenia were common. (Funded by Stemline Therapeutics and the Leukemia and Lymphoma Society Therapy Acceleration Program; ClinicalTrials.gov number, .) Patients with blastic plasmacytoid dendritic-cell neoplasm, an aggressive hematologic cancer, were treated with the cytotoxin tagraxofusp in a dose-escalation case series. Previously untreated patients had a 72% complete response rate, and 45% underwent stem-cell transplantation. Toxic effects included hepatic dysfunction, thrombocytopenia, and capillary leak syndrome.