RESUMO
Chronic lymphocytic leukaemia (CLL) is a frequent disease in which the genetic alterations determining the clinicobiological behaviour are not fully understood. Here we describe a comprehensive evaluation of the genomic landscape of 452 CLL cases and 54 patients with monoclonal B-lymphocytosis, a precursor disorder. We extend the number of CLL driver alterations, including changes in ZNF292, ZMYM3, ARID1A and PTPN11. We also identify novel recurrent mutations in non-coding regions, including the 3' region of NOTCH1, which cause aberrant splicing events, increase NOTCH1 activity and result in a more aggressive disease. In addition, mutations in an enhancer located on chromosome 9p13 result in reduced expression of the B-cell-specific transcription factor PAX5. The accumulative number of driver alterations (0 to ≥4) discriminated between patients with differences in clinical behaviour. This study provides an integrated portrait of the CLL genomic landscape, identifies new recurrent driver mutations of the disease, and suggests clinical interventions that may improve the management of this neoplasia.
Assuntos
Leucemia Linfocítica Crônica de Células B/genética , Mutação/genética , Regiões 3' não Traduzidas/genética , Processamento Alternativo/genética , Linfócitos B/metabolismo , Proteínas de Transporte/genética , Cromossomos Humanos Par 9/genética , Análise Mutacional de DNA , DNA de Neoplasias/genética , Proteínas de Ligação a DNA , Elementos Facilitadores Genéticos/genética , Genômica , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Fator de Transcrição PAX5/biossíntese , Fator de Transcrição PAX5/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Receptor Notch1/genética , Receptor Notch1/metabolismo , Fatores de Transcrição/genéticaRESUMO
Mobile genetic elements (MGEs) encoding virulence and resistance genes are widespread in bacterial pathogens, but it has remained unclear how they occasionally jump to new host species. Staphylococcus aureus clones exchange MGEs such as S. aureus pathogenicity islands (SaPIs) with high frequency via helper phages. Here we report that the S. aureus ST395 lineage is refractory to horizontal gene transfer (HGT) with typical S. aureus but exchanges SaPIs with other species and genera including Staphylococcus epidermidis and Listeria monocytogenes. ST395 produces an unusual wall teichoic acid (WTA) resembling that of its HGT partner species. Notably, distantly related bacterial species and genera undergo efficient HGT with typical S. aureus upon ectopic expression of S. aureus WTA. Combined with genomic analyses, these results indicate that a 'glycocode' of WTA structures and WTA-binding helper phages permits HGT even across long phylogenetic distances thereby shaping the evolution of Gram-positive pathogens.