Dataset Information

Discovery of novel recurrent mutations and rearrangements in early T-cell precursor acute lymphoblastic leukaemia by whole genome sequencing

ABSTRACT: Acute lymphoblastic leukaemia with early T-cell precursor immunophenotype (ETP ALL) is a highly aggressive subtype of ALL of unknown aetiology. To gain insights into the genetic basis of this disease, we performed whole genome sequencing of tumour and normal DNA of 12 children with ETP ALL. Analysis of structural and sequence variants in this discovery cohort, and mutation recurrence screening in a panel of 51 ETP and 43 non ETP ALL samples identified a high frequency of activating mutations in genes regulating cytokine receptor and Ras signalling, including IL7R, NRAS, KRAS, FLT3, BRAF, JAK1 and JAK3 in ETP ALL. Moreover, we identified multiple new targets of mutation in including GATA3, EP300, RUNX1, DNM2, ECT2L, HNRNPA1 and HNRNPR, as well as genes known to be mutated in T-ALL, including NOTCH1, PHF6, and WT1.. Five of 12 ETP ALL cases harboured novel chromosomal translocations, several of which accompanied complex multichromosomal rearrangements and resulted in the expression of chimeric in-frame fusion genes disrupting hematopoietic regulators, including ETV6-INO80D, NAP1L1-MLLT10 and RUNX1-EVX1. These results indicate that although ETP ALL is genetically heterogeneous, activation of Ras and cytokine receptor signalling distinguishes this disease from non-ETP ALL. These findings suggest that targeting this pathway may improve the currently dismal outcome of this disease.

ORGANISM(S): Homo sapiens

PROVIDER: GSE33315 | GEO | 2012/01/10

SECONDARY ACCESSION(S): PRJNA149299

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Project description:CREST The accurate identification of structural variations using whole-genome DNA sequencing data generated by next-generation sequencing technology is extremely difficult. To address this challenge, we have developed CREST, an algorithm that uses sequencing reads with partial alignments to the reference human genome (so-called soft-clipped reads) to directly map the breakpoints of somatic structural variations. We applied CREST to paired tumor/normal whole genome sequencing data from five cases of T-lineage acute lymphoblastic leukemia (T-ALL). A total of 110 somatic structural variants were identified, >80% of which were validated by genomic PCR and Sanger sequencing. The validated structural variants included 31 inter-chromosomal translocations, 19 intra-chromosomal translocations, one inversion, 22 deletions and 16 insertions. A comparison of the results generated with CREST to those obtained using the traditional paired-end discordant mapping methods demonstrate CREST to have a much higher sensitivity and specificity. In addition, application of CREST to publicly available whole-genome sequencing data from the human melanoma cancer cell line COLO-829 demonstrated the identification of 50 novel structural variations not detected using the standard methods, 20 of which were selected for validation with a 90% success rate. These data demonstrate that direct mapping of soft-clipped reads offers an improved method for detecting structural variants at the nucleotide level of resolution. T-ALL Early T-cell precursor acute lymphoblastic leukaemia (ETP ALL) is an aggressive malignancy of unknown genetic basis. We performed whole-genome sequencing of 12 ETP ALL cases and assessed the frequency of the identified somatic mutations in 94 T-cell acute lymphoblastic leukaemia cases. ETP ALL was characterized by activating mutations in genes regulating cytokine receptor and RAS signalling (67% of cases; NRAS, KRAS, FLT3, IL7R, JAK3, JAK1, SH2B3 and BRAF), inactivating lesions disrupting haematopoietic development (58%; GATA3, ETV6, RUNX1, IKZF1 and EP300) and histone-modifying genes (48%; EZH2, EED, SUZ12, SETD2 and EP300). We also identified new targets of recurrent mutation including DNM2, ECT2L and RELN. The mutational spectrum is similar to myeloid tumours, and moreover, the global transcriptional profile of ETP ALL was similar to that of normal and myeloid leukaemia haematopoietic stem cells. These findings suggest that addition of myeloid-directed therapies might improve the poor outcome of ETP ALL.

Dataset Information

Discovery of novel recurrent mutations and rearrangements in early T-cell precursor acute lymphoblastic leukaemia by whole genome sequencing

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets