RESUMO
Interstitial 14q32 deletions involving IGH gene are infrequent events in chronic lymphocytic leukemia (CLL), affecting less than 5% of patients. To date, little is known about their clinical impact and molecular underpinnings, and its mutational landscape is currently unknown. In this work, a total of 871 CLLs were tested for the IGH break-apart probe, and 54 (6.2%) had a 300 kb deletion of 3'IGH (del-3'IGH CLLs), which contributed to a shorter time to first treatment (TFT). The mutational analysis by next-generation sequencing of 317 untreated CLLs (54 del-3'IGH and 263 as the control group) showed high mutational frequencies of NOTCH1 (30%), ATM (20%), genes involved in the RAS signaling pathway (BRAF, KRAS, NRAS, and MAP2K1) (15%), and TRAF3 (13%) within del-3'IGH CLLs. Notably, the incidence of TRAF3 mutations was significantly higher in del-3'IGH CLLs than in the control group (p < .001). Copy number analysis also revealed that TRAF3 loss was highly enriched in CLLs with 14q deletion (p < .001), indicating a complete biallelic inactivation of this gene through deletion and mutation. Interestingly, the presence of mutations in the aforementioned genes negatively refined the prognosis of del-3'IGH CLLs in terms of overall survival (NOTCH1, ATM, and RAS signaling pathway genes) and TFT (TRAF3). Furthermore, TRAF3 biallelic inactivation constituted an independent risk factor for TFT in the entire CLL cohort. Altogether, our work demonstrates the distinct genetic landscape of del-3'IGH CLL with multiple molecular pathways affected, characterized by a TRAF3 biallelic inactivation that contributes to a marked poor outcome in this subgroup of patients.
Assuntos
Leucemia Linfocítica Crônica de Células B , Genes de Cadeia Pesada de Imunoglobulina , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Mutação , Prognóstico , Fator 3 Associado a Receptor de TNF/genéticaRESUMO
Chromosome 14q32 rearrangements/translocations involving the immunoglobulin heavy chain (IGH) are rarely detected in chronic lymphocytic leukemia (CLL). The prognostic significance of the IGH translocation is controversial and its mutational profile remains unknown. Here, we present for the first time a comprehensive next-generation sequencing (NGS) analysis of 46 CLL patients with IGH rearrangement (IGHR-CLLs) and we demonstrate that IGHR-CLLs have a distinct mutational profile with recurrent mutations in NOTCH1, IGLL5, POT1, BCL2, FBXW7, ZMYM3, MGA, BRAF and HIST1H1E genes. Interestingly, BCL2 and FBXW7 mutations were significantly associated with this subgroup and almost half of BCL2, IGLL5 and HISTH1E mutations reported were previously identified in non-Hodgkin lymphomas. Notably, IGH/BCL2 rearrangements were associated with a lower mutation frequency and carried BCL2 and IGLL5 mutations, while the other IGHR-CLLs had mutations in genes related to poor prognosis (NOTCH1, SF3B1 and TP53) and shorter time to first treatment (TFT). Moreover, IGHR-CLLs patients showed a shorter TFT than CLL patients carrying 13q-, normal fluorescence in situ hybridization (FISH) and +12 CLL, being this prognosis particularly poor when NOTCH1, SF3B1, TP53, BIRC3 and BRAF were also mutated. The presence of these mutations not only was an independent risk factor within IGHR-CLLs, but also refined the prognosis of low-risk cytogenetic patients (13q-/normal FISH). Hence, our study demonstrates that IGHR-CLLs have a distinct mutational profile from the majority of CLLs and highlights the relevance of incorporating NGS and the status of IGH by FISH analysis to refine the risk-stratification CLL model.
Assuntos
Redes Reguladoras de Genes , Cadeias Pesadas de Imunoglobulinas/genética , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Translocação Genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromossomos Humanos Par 13/genética , Cromossomos Humanos Par 14/genética , Feminino , Predisposição Genética para Doença , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Sequência de DNARESUMO
Erythropoietin (rhEPO) has been used in different surgical procedures as a method for saving allogeneic blood, with variable efficacy. Forty consecutive patients entered the pre-operative autologous blood donation (PABD) program, and during donations hemoglobin fell below 115 g/l; they received rhEPO 40,000 U every week for three or four weeks (group 1). As control group, 35 consecutive patients who entered the PABD program were studied; during donations, hemoglobin levels in these patients fell below 115 g/l, but rhEPO was not administered (group 2). Pre-surgery hemoglobin levels were higher in patients who received rhEPO (134 g/l vs. 121 g/l; p<0.0002), and an average of 3.47 doses were administered. The number of transfused autologous units was 1.6 in group 1 and 2.1 in group 2 (p<0.05), while the number of allogeneic units was 0.9 and 0.1, respectively (p<0.0005), so that only 5% of patients treated with rhEPO required some allogeneic unit, as compared to 40% of those who did not receive rhEPO (p<0.0005). There were no relevant adverse effects, but in two patients from group 1, rhEPO treatment had to be discontinued because the level of hemoglobin exceeded 150 g/l. The mean duration of hospital admission was shorter in the patients who received rhEPO than in those who only underwent PABD (8 days vs. 11.8 days; NS). When adequately used, rhEPO is an effective and safe alternative to the use of allogeneic blood.