Pax5 restoration in a mouse model of B progenitor acute lymphoblastic leukemia
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE52870 | GEO | 2014/06/18
SECONDARY ACCESSION(S): PRJNA230380
REPOSITORIES: GEO
Similar Datasets
Project description:Hypomorphic mutations of PAX5 occur in one third of B-progenitor acute lymphoblastic leukemias (B-ALLs), however their functional consequences remain undefined. Here we employ advanced transgenic RNAi in mice to suppress endogenous Pax5 expression in the hematopoietic compartment in vivo, which co-operates with activated STAT5 to induce B-ALL. In this model, restoring endogenous Pax5 expression in established B-ALL induces transcriptional and immunophenotypic changes reminiscent of normal B cell differentiation, disabling leukemia-initiating capacity and ultimately causing leukemia clearance. Comparison of leukemias harvested from triplicate untreated mice versus triplicate Dox-treated (3 days) mice
2014-06-18 | E-GEOD-52870 | biostudies-arrayexpress
Project description:Hypomorphic mutations of the transcription factor PAX5 occur in one third of B-progenitor acute lymphoblastic leukemias (B-ALLs). To identify PAX5-regulated genes in B-ALL, here we employ inducible expression of PAX5 in a human B-ALL cell line (REH) that harbors a loss-of-function mutation in PAX5. In this model, inducing PAX5 expression is associated with competitive disadvantage.
2014-06-18 | GSE57480 | GEO
Project description:Hypomorphic mutations of the transcription factor PAX5 occur in one third of B-progenitor acute lymphoblastic leukemias (B-ALLs). To identify PAX5-regulated genes in B-ALL, here we employ inducible expression of PAX5 in a human B-ALL cell line (REH) that harbors a loss-of-function mutation in PAX5. In this model, inducing PAX5 expression is associated with competitive disadvantage. Comparison of REH cell lines with Dox-inducible expression of PAX5-IRES-GFP, or control GFP alone. GFP positive cells were isolated by FACS.
2014-06-18 | E-GEOD-57480 | biostudies-arrayexpress
Project description:PAX5, one of nine members of the mammalian paired box (PAX) family of transcription factors, plays an important role in B cell development. Approximately one-third of individuals with pre-B acute lymphoblastic leukemia (ALL) acquire heterozygous inactivating mutations of PAX5 in malignant cells, and heterozygous germline loss-offunction PAX5 mutations cause autosomal dominant predisposition to ALL. At least in mice, Pax5 is required for pre-B cell maturation, and leukemic remission occurs when Pax5 expression is restored in a Pax5-deficient mouse model of ALL. Together, these observations indicate that PAX5 deficiency reversibly drives leukemogenesis. PAX5 and its two most closely related paralogs, PAX2 and PAX8, which are not mutated in ALL, exhibit overlapping expression and function redundantly during embryonic development. However, PAX5 alone is expressed in lymphocytes, while PAX2 and PAX8 are predominantly specific to kidney and thyroid, respectively. We show that forced expression of PAX2 or PAX8 complements PAX5 loss-of-function mutation in ALL cells as determined by modulation of PAX5 target genes, restoration of immunophenotypic and morphological differentiation, and, ultimately, reduction of replicative potential. Activation of PAX5 paralogs, PAX2 or PAX8, ordinarily silenced in lymphocytes, may therefore represent a novel approach for treating PAX5-deficient ALL. In pursuit of this strategy, we took advantage of the fact that, in kidney, PAX2 is upregulated by extracellular hyperosmolarity. We found that hyperosmolarity, at potentially clinically achievable levels, transcriptionally activates endogenous PAX2 in ALL cells via a mechanism dependent on NFAT5, a transcription factor coordinating response to hyperosmolarity. We also found that hyperosmolarity upregulates residual wild type PAX5 expression in ALL cells and modulates gene expression, including in PAX5-mutant primary ALL cells. These findings specifically demonstrate that osmosensing pathways may represent a new therapeutic target for ALL and more broadly point toward the possibility of using gene paralogs to rescue mutations driving cancer and other diseases.
2018-09-11 | GSE109860 | GEO
Project description:PAX5 is a tumor suppressor in B-ALL, while the role of PAX5 fusion proteins in B-ALL development is largely unknown. Here we studied the function of PAX5-ETV6 and PAX5- FOXP1 in mice expressing these proteins from the Pax5 locus. Both proteins arrested Blymphopoiesis at the pro-B-to-pre-B cell transition and, contrary to their proposed dominantnegative role, did not interfere with the expression of most Pax5 target genes. Pax5-Etv6, but not Pax5-Foxp1, cooperated with loss of the Cdkna2a/b tumor suppressor in promoting B-ALL development. Regulated Pax5-Etv6 target genes identified in these B-ALLs encode proteins implicated in pre-BCR signaling and migration/adhesion, which could contribute to the proliferation, survival and tissue infiltration of leukemic B-cells. Together with similar observations made in human PAX5-ETV6+ B-ALLs, these data identified PAX5-ETV6 as a potent oncoprotein.
2017-02-06 | GSE84987 | GEO
Project description:PAX5 is a tumor suppressor in B-ALL, while the role of PAX5 fusion proteins in B-ALL development is largely unknown. Here we studied the function of PAX5-ETV6 and PAX5- FOXP1 in mice expressing these proteins from the Pax5 locus. Both proteins arrested Blymphopoiesis at the pro-B-to-pre-B cell transition and, contrary to their proposed dominantnegative role, did not interfere with the expression of most Pax5 target genes. Pax5-Etv6, but not Pax5-Foxp1, cooperated with loss of the Cdkna2a/b tumor suppressor in promoting B-ALL development. Regulated Pax5-Etv6 target genes identified in these B-ALLs encode proteins implicated in pre-BCR signaling and migration/adhesion, which could contribute to the proliferation, survival and tissue infiltration of leukemic B-cells. Together with similar observations made in human PAX5-ETV6+ B-ALLs, these data identified PAX5-ETV6 as a potent oncoprotein. 36 samples in total: A) 24 RNA-Seq samples in 5 cell types: pro-B (5 genotypes, 2-4 replicates) large pre-B (2 genotypes, 2 replicates each) small pre-B (1 genotype, 2 replicates) lymph node (1 genotype, 3 replicates) bone marrow (1 genotype, 2 replicates) B) 12 ChIP-Seq samples in 2 cell types: pro-B (H3K27me3, H3K9ac, H3K4me2, H3K4me3, H3K27ac, 1 replicate each; Pax5Etv6 ChIP, Prd ChIP, 2 replicates each; Pax5 ChIP 1 replicate) lymph node (1 genotype, 2 replicates).
2016-07-30 | E-GEOD-84987 | biostudies-arrayexpress
Project description:While PAX5 is an important tumor suppressor in B-ALL, it is also involved in oncogenic translocations coding for PAX5 fusion proteins. PAX5-JAK2 encodes a protein consisting of the PAX5 DNA-binding region fused to the constitutively active JAK2 kinase domain. Here, we studied the oncogenic function of PAX5-JAK2 in a mouse model expressing it from the endogenous Pax5 locus. The Pax5Jak2/+ mice rapidly developed an aggressive B-ALL in the absence of another cooperating mutation. The DNA-binding function and kinase activity of Pax5-Jak2, as well as IL-7 signaling, all contributed to leukemia development. Interestingly, all Pax5Jak2/+ tumors lost the wild-type Pax5 allele, allowing efficient DNA binding of Pax5-Jak2. While we could not find evidence for a nuclear role of Pax5-Jak2 as an epigenetic regulator, active phosphorylated Stat5 was present at a high level in Pax5Jak2/+ B-ALL tumors, consistent with increased expression of Stat5 target genes. Together, these data identified Pax5-Jak2 as an important nuclear driver of leukemia formation by maintaining phosphorylated Stat5 levels in the nucleus.
2022-02-04 | GSE174775 | GEO
Project description:Heterochromatin has a high density of DNA and low rates of gene transcription.H3k9me3 is a conserved histone modification, and is best known for its role in constitutive heterochromatin formation.H1155, which is a neuroendocrine large cell lung cancer cell line, has a dense nucleus and a high level of occupancy of H3K9me3. PAX5 is a neurogenesis and B lymphocyte development transcription factor, and endogenous expressed in neuroendocrine carcinoma, including H1155 cell line. To assess whether PAX5 promotes heterochromatin formation in H1155, we knock out PAX5 in H1155 cell (KO-PAX5) by CRISPR/Cas9 and use H3K9me3 to performed ChIP-seq.
2024-01-17 | GSE165035 | GEO
Project description:PAX5-KIDINS220 (PAX5-K220) is a novel chimeric fusion gene identified in a pediatric Philadelphia chromosome (Ph)-like acute lymphoblastic leukemia (ALL) patient, but the function of the encoded fusion protein has not yet been analyzed.We successfully generated PAX5-K220 expressing cells and demonstrate that PAX5-K220 is a nuclear protein. In addition, PAX5-K220 activates JAK2-STAT5 pathway through the repression of Socs5, a known negative regulator of JAK-STAT pathway. However, although identified in Ph-like ALL, PAX5-K220 does not induce IL-3-independent proliferation when transduced in the IL-3-dependent Ba/F3 murine leukemia cells, but rather attenuates growth. Luciferase reporter assay reveals that PAX5-K220 inhibits wild type PAX5 transcriptional activity in a dominant-negative fashion like other PAX5-related fusion proteins, and may contribute to lymphocyte differentiation block. These results reveal that PAX5-K220 certainly shares the character with other PAX5-related fusion proteins rather than other fusion proteins with tyrosine kinase activity identified in Ph-like ALL, and did not contribute to proliferation activity.
2019-03-01 | GSE127485 | GEO
Project description:B lymphopoiesis is a key developmental event orchestrated by a complex combinatorial action of lineage-specific transcription factors. In early B cell progenitors, lineage commitment is directly mediated by the master regulator PAX5, whose deficiency is commonly associated with B cell Acute Lymphoblastic Leukemia (B-ALL). Despite its essential role in mammalian immunity, the regulatory mechanisms that control PAX5 function remain largely unknown. Here we show that NAD+-dependent enzyme SIRT7 coordinates B cell development progression through PAX5. We have identified a SIRT7-dependent regulatory switch based on dynamic deacetylation of a single PAX5 residue, which controls its activity and thereby B cell fate. While a PAX5K198 acetylated mimic is incapable of inducing both B cell development and identity due to reduced protein stability and impaired binding to chromatin, deacetylation of this residue boosts PAX5 activity, leading to massive gene repression and in vivo restoration of B cell commitment but not differentiation. These findings suggest an unexpected uncoupling of hematopoietic differentiation and lineage commitment. Further supporting the functional relevance of the SIRT7-PAX5 axis, the interplay between both factors is conserved in human B-ALL, where high SIRT7 expression is an independent good prognostic factor. Our findings unveil a crucial mechanism in the regulation of B cell production based on the control of PAX5 function and underscore the key role of Sirtuins in the regulation of the immune system.
2024-09-20 | PXD046457 | Pride