This section shows a summary for the selected study (COSU identifier) or publication (COSP identifier). Studies may have been performed by the Sanger Institute Cancer Genome Project, or imported from the ICGC/TCGA. You can see more information on the help pages.
- Reference
- Therapy-induced mutations drive the genomic landscape of relapsed acute lymphoblastic leukemia.
- Paper ID
- COSP47301
- Authors
- Affiliation
- Key Laboratory of Pediatric Hematology and Oncology Ministry of Health.
- Journal
-
Blood, 2019
ISSN: 1528-0020
PMID: 31697823 (view at PubMed or Europe PMC) - Abstract
- To study the mechanisms of relapse in acute lymphoblastic leukemia (ALL), we performed whole-genome sequencing of 103 diagnosis-relapse-germline trios and ultra-deep sequencing of 208 serial samples in 16 patients. Relapse-specific somatic alterations were enriched in 12 genes (NR3C1, NR3C2, TP53, NT5C2, FPGS, CREBBP, MSH2, MSH6, PMS2, WHSC1, PRPS1, and PRPS2) involved in drug response. Their prevalence was 17% in very early relapse (<9 months from diagnosis), 65% in early relapse (9-36 months), and 32% in late relapse (>36 months) groups. Convergent evolution, where multiple subclones harbor mutations in the same drug resistance gene, was observed in six relapses and confirmed by single-cell sequencing in one case. Mathematical modeling and mutational signature analysis indicated that early relapse resistance acquisition was frequently two-step process where a persistent clone survived initial therapy, and later acquired bona fide resistance mutations during therapy. In contrast, very early relapses arose from pre-existing resistant clone(s). Two novel relapse-specific mutational signatures, one of which was caused by thiopurine treatment based on in vitro drug exposure experiments, were identified in early and late relapses but were absent from 2,540 pan-cancer diagnosis samples and 129 non-ALL relapses. The novel signatures were detected in 27% of relapsed ALLs and were responsible for 46% of acquired resistance mutations in NT5C2, PRPS1, NR3C1, and TP53. These results suggest that chemotherapy-induced drug resistance mutations facilitate a subset of pediatric ALL relapses.
- Paper Status
- Curated