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Status |
Public on Mar 18, 2016 |
Title |
CLIC5: a novel ETV6 target gene in childhood acute lymphoblastic leukemia |
Organism |
Homo sapiens |
Experiment type |
Expression profiling by high throughput sequencing
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Summary |
Background: The most common rearrangement in childhood precursor B-cell acute lymphoblastic leukemia (pre-B ALL) is the t(12;21)(p13;q22) translocation resulting in the ETV6-AML1 fusion gene. A frequent concomitant event is the loss of the residual ETV6 allele suggesting a critical role for the ETV6 transcriptional repressor in the etiology of pre-B ALL. However, the precise mechanism through which loss of functional ETV6 contributes to disease pathogenesis is still unclear Results: To investigate the impact of ETV6 loss on the transcriptional network and identify new transcriptional targets of ETV6, we used whole transcriptome analysis of both pre-B leukemic cell lines and pre-B ALL patients combined with chromatin immunoprecipitation. Using this integrative approach, we identified 4 novel direct ETV6 target genes: CLIC5, BIRC7, ANGPTL2 and WBP1L. To further evaluate the role of chloride intracellular channel protein CLIC5 in leukemogenesis, we generated cell lines overexpressing CLIC5 and demonstrated an increased resistance to hydrogen peroxide-induced apoptosis. We further described the implications of CLIC5’s ion channel activity in lysosomal-mediated cell death, possibly by modulating the function of transferrin receptor with which it co-localizes intracellularly. Conclusion: For the first time, we showed that loss of ETV6 leads to significant overexpression of CLIC5, which in turn leads to decreased lysosome-mediated apoptosis. Our data suggest that heightened CLIC5 activity could promote a permissive environment for oxidative-stress induced DNA damage accumulation and thereby contribute to leukemogenesis.
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Overall design |
To identify direct targets of ETV6, we first designed an in vitro RNA-seq experiment using ETV6-/- Reh-derived clones. Cells were transduced with lentiviral constructs to express ETV6-His and ETV6ΔETS_NLS-His. Total RNA was extracted from stable cell populations and RNA-seq libraries were sequenced. Expression profiles were analyzed using EdgeR. Gene expression profiles in ETV6-His cells were first compared with ETV6ΔETS_NLS-His and pLENTI cells to identify repressed genes (FDR ≤ 0.1). We then included data from the ETV6ΔETS_NLS-His vs. pLENTI comparison and further considered genes whose expression remains constant (p-value ≥ 0.05 or logFC ≥ -0.5) which are more likely to be direct ETV6 targets. Finally, only genes that showed a specific overexpression in t(12;21)-positive childhood pre-B ALL patients were considered.
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Contributor(s) |
Neveu B, Spinella J, Richer C, Lagacé K, Cassart P, Lajoie M, Jananji S, Healy J, Hickson GR, Sinnett D |
Citation(s) |
27540136 |
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Submission date |
Mar 18, 2016 |
Last update date |
May 15, 2019 |
Contact name |
Daniel Sinnett |
E-mail(s) |
daniel.sinnett@umontreal.ca
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Organization name |
CHU Sainte-Justine
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Street address |
3175 Cote-Sainte-Catherine
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City |
Montreal |
State/province |
Quebec |
ZIP/Postal code |
H3T 1C5 |
Country |
Canada |
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Platforms (2) |
GPL16558 |
AB 5500 Genetic Analyzer (Homo sapiens) |
GPL16791 |
Illumina HiSeq 2500 (Homo sapiens) |
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Samples (25)
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Relations |
BioProject |
PRJNA315627 |
SRA |
SRP071966 |