ETV6-RUNX1 interacts with a region in SPIB intron 1 to regulate gene expression in pre-B-cell acute lymphoblastic leukemia.
PMID 30986496 | DOI 10.1016/j.exphem.2019.03.004 · Experimental hematology · 2019
The most frequently occurring genetic abnormality in pediatric B-lymphocyte-lineage acute lymphoblastic leukemia is the t(12;21) chromosomal translocation that results in a ETV6-RUNX1 (also known as TEL-AML1) fusion gene. Expression of ETV6-RUNX1 induces a preleukemic condition leading to acquisition of secondary driver mutations, but the mechanism is poorly understood. SPI-B (encoded by SPIB) is an important transcriptional activator of B-cell development and differentiation. We hypothesized that SPIB is directly transcriptionally repressed by ETV6-RUNX1. Using chromatin immunoprecipitation, we identified a regulatory region in the first intron of SPIB that interacts with ETV6-RUNX1. Mutation of the RUNX1 binding site in SPIB intron 1 prevented transcriptional repression in transient transfection assays. Next, we sought to determine to what extent gene expression in REH cells can be altered by ectopic SPI-B expression. SPI-B expression was forced using CRISPR-mediated gene activation and also using a retroviral vector. Forced expression of SPI-B resulted in altered gene expression and, at high levels, impaired cell proliferation and induced apoptosis. Finally, we identified CARD11 and CDKN1A (encoding p21) as transcriptional targets of SPI-B involved in regulation of proliferation and apoptosis. Taken together, this study identifies SPIB as an important target of ETV6-RUNX1 in regulation of B-cell gene expression in t(12;21) leukemia.
Validated evidence
| Type | Entity | Source evidence | Confidence | Extractor |
|---|---|---|---|---|
| gene | SPIB | “ETV6-RUNX1 interacts with a region in SPIB intron 1 to regulate gene expression in pre-B-cell acute lymphoblastic leukemia.” | 0.98 | hgnc_dict_v1 |
| gene | RUNX1 | “Mutation of the RUNX1 binding site in SPIB intron 1 prevented transcriptional repression in transient transfection assays.” | 0.98 | hgnc_dict_v1 |
| gene | CARD11 | “Finally, we identified CARD11 and CDKN1A (encoding p21) as transcriptional targets of SPI-B involved in regulation of proliferation and apoptosis.” | 0.98 | hgnc_dict_v1 |
| gene | CDKN1A | “Finally, we identified CARD11 and CDKN1A (encoding p21) as transcriptional targets of SPI-B involved in regulation of proliferation and apoptosis.” | 0.98 | hgnc_dict_v1 |
| phenotype | leukemia | “ETV6-RUNX1 interacts with a region in SPIB intron 1 to regulate gene expression in pre-B-cell acute lymphoblastic leukemia.” | 0.98 | phenotype_alias_lexicon_v2 |