Acquired Initiating Mutations in Early Hematopoietic Cells of CLL Patients

作者:Damm Frederik; Mylonas Elena; Cosson Adrien; Yoshida Kenichi; Della Valle Veronique; Mouly Enguerran; Diop M'boyba; Scourzic Laurianne; Shiraishi Yuichi; Chiba Kenichi; Tanaka Hiroko; Miyano Satoru; Kikushige Yoshikane; Davi Frederick; Lambert Jerome; Gautheret Daniel; Merle Beral Helene; Sutton Laurent; Dessen Philippe; Solary Eric; Akashi Koichi; Vainchenker William; Mercher Thomas; Droin Nathalie; Ogawa Seishi; Florence Nguyen Khac; Bernard Olivier A*
来源:Cancer Discovery, 2014, 4(9): 1088-1101.
DOI:10.1158/2159-8290.CD-14-0104

摘要

Appropriate cancer care requires a thorough understanding of the natural history of the disease, including the cell of origin, the pattern of clonal evolution, and the functional consequences of the mutations. Using deep sequencing of flow-sorted cell populations from patients with chronic lymphocytic leukemia (CLL), we established the presence of acquired mutations in multipotent hematopoietic progenitors. Mutations affected known lymphoid oncogenes, including BRAF, NOTCH1, and SF3B1. NFKBIE and EGR2 mutations were observed at unexpectedly high frequencies, 10.7% and 8.3% of 168 advanced-stage patients, respectively. EGR2 mutations were associated with a shorter time to treatment and poor overall survival. Analyses of BRAF and EGR2 mutations suggest that they result in deregulation of B-cell receptor (BCR) intracellular signaling. Our data propose disruption of hematopoietic and early B-cell differentiation through the deregulation of pre-BCR signaling as a phenotypic outcome of CLL mutations and show that CLL develops from a pre-leukemic phase. SIGNIFICANCE: The origin and pathogenic mechanisms of CLL are not fully understood. The current work indicates that CLL develops from pre-leukemic multipotent hematopoietic progenitors carrying somatic mutations. It advocates for abnormalities in early B-cell differentiation as a phenotypic convergence of the diverse acquired mutations observed in CLL.