A Novel PI3K Regulator, ARID4B, Presents Synthetic Essentiality in PTEN-deficient Prostate Cancer
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA479839 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Phosphatase and tensin homologue (PTEN) is the most frequently mutated tumor suppressor gene in human prostate cancer. Synthetic essentiality is defined as cancer that harbors a specific tumor suppressor deficiency is dependent on synthetic-essential genes for the malignant phenotypes. Recently, targeting such synthetic-essential genes has become an attractive treatment approach for cancers that acquire loss-of-function mutations in tumor suppressor genes. Here, we show that AT-rich interaction domain 4B (ARID4B) functions as a synthetic-essential gene in prostate tumorigenesis driven by PTEN deficiency. This functional interaction between ARID4B and PTEN is recapitulated in the mouse model carrying prostate-specific deletions of Pten and Arid4b in which ablation of ARID4B attenuated prostate cancer progression elicited by loss of PTEN. Although the tumor suppressor function of PTEN is most attributed to its lipid phosphatase activity that counters the PI3K action in cytoplasm, we identified the PTEN-ARID4B-PI3K axis in which nuclear PTEN inhibits expression of ARID4B, while ARID4B serves as a transcriptional activator of the PI3K subunits PIK3CA and PIK3R2 to trigger the PI3K/AKT pathway. Our study further demonstrated that the reciprocal binding of ARID4B and histone H1 to the PIK3CA and PIK3R2 promoters modulates chromatin condensation, indicating a mechanism by which ARID4B activates these promoters. Finally, a three-gene signature consisting of PTEN, ARID4B, and PI3K substantially improves the predictive power for tumor recurrence in human prostate cancer patients, underscoring the clinical significance of this newly identified PTEN-ARID4B-PI3K axis. These findings reveal a novel synthetic-essential relationship between ARID4B and PTEN, thus exposing a previously unidentified cancer-specific vulnerability, and supporting ARID4B as a potential therapeutic target for prostate cancer patients with PTEN mutations.
2019-08-23 | GSE116668 | GEO
Project description:Phosphatase and tensin homologue (PTEN) is the most frequently mutated tumor suppressor gene in human prostate cancer. Synthetic essentiality is defined as cancer that harbors a specific tumor suppressor deficiency is dependent on synthetic-essential genes for the malignant phenotypes. Recently, targeting such synthetic-essential genes has become an attractive treatment approach for cancers that acquire loss-of-function mutations in tumor suppressor genes. Here, we show that AT-rich interaction domain 4B (ARID4B) functions as a synthetic-essential gene in prostate tumorigenesis driven by PTEN deficiency. This functional interaction between ARID4B and PTEN is recapitulated in the mouse model carrying prostate-specific deletions of Pten and Arid4b in which ablation of ARID4B attenuated prostate cancer progression elicited by loss of PTEN. Although the tumor suppressor function of PTEN is most attributed to its lipid phosphatase activity that counters the PI3K action in cytoplasm, we identified the PTEN-ARID4B-PI3K axis in which nuclear PTEN inhibits expression of ARID4B, while ARID4B serves as a transcriptional activator of the PI3K subunits PIK3CA and PIK3R2 to trigger the PI3K/AKT pathway. Our study further demonstrated that the reciprocal binding of ARID4B and histone H1 to the PIK3CA and PIK3R2 promoters modulates chromatin condensation, indicating a mechanism by which ARID4B activates these promoters. Finally, a three-gene signature consisting of PTEN, ARID4B, and PI3K substantially improves the predictive power for tumor recurrence in human prostate cancer patients, underscoring the clinical significance of this newly identified PTEN-ARID4B-PI3K axis. These findings reveal a novel synthetic-essential relationship between ARID4B and PTEN, thus exposing a previously unidentified cancer-specific vulnerability, and supporting ARID4B as a potential therapeutic target for prostate cancer patients with PTEN mutations.
2019-08-23 | GSE116669 | GEO
Project description:A Novel PI3K Regulator, ARID4B, Presents Synthetic Essentiality in PTEN-deficient Prostate Cancer [ChIP-seq]
| PRJNA479843 | ENA
Project description:A Novel PI3K Regulator, ARID4B, Presents Synthetic Essentiality in PTEN-deficient Prostate Cancer [RNA-seq]
| PRJNA479842 | ENA
Project description:This SuperSeries is composed of the SubSeries listed below.
2019-08-23 | GSE116670 | GEO
Project description:High Arid4b promotes mammary tumor growth and metastasis in mouse model systems, and is associated with poor metastasis-free survival in human breast cancer patients. Through shRNA-mediated knockdown, we demonstrated that loss of Arid4b significantly inhibits the ability of mouse breast cancer cells to metastasize to the lungs. We performed microarray expression and subsequent network analysis to identify genes diferentially regulated as a consequence of Arid4b knockdown. The highly metastatic mouse breast cancer cell line 6DT1 was transduced with lentiviral shRNAs targeting Arid4b (RMM4534-NM_194262, Open Biosystems) or scrambled control in the same pLKO.1 vector backbone. Stably transduced cells were selected with puromycin, then total RNA was isolated from pooled clones.
2012-04-23 | E-GEOD-35731 | biostudies-arrayexpress
Project description: Not available
| S-EPMC6760172 | biostudies-literature
Project description:To comprehensively analyze the PTEN-PI3K-AKT pathway in T-ALL, we examined diagnostic DNA samples from a series of children with T-ALL by array CGH and sequence analysis, and identified genetic lesions in PTEN, PI3K or AKT in 47.7 % (n = 21 of 44) of cases. Furthermore, we identified a striking clustering of PTEN mutations in exon 7 in primary T-ALL patient samples, all of which encode mutations predicted to truncate the C2 domain without disrupting the phosphatase domain of PTEN. Induction chemotherapy failed in three of the four patients whose lymphoblasts harbored PTEN deletions at the time of diagnosis, while no induction failures occurred in the 12 cases with PTEN exon 7 mutations (P = 0.007), suggesting that PTEN deletion has more adverse therapeutic consequences than mutational disruptions that preserve the phosphatase domain. These findings provide a firm rationale for the development of therapies targeting the PI3K-AKT pathway in T-ALL.
2009-12-01 | GSE14959 | GEO
Project description:Hyperactivation of the phosphatydil-inositol-3' phosphate kinase (PI3K)/AKT pathway is observed in most NSCLCs, promoting proliferation, migration, invasion and resistance to therapy. AKT can be activated through several mechanisms that include loss of the negative regulator PTEN, activating mutations of the catalytic subunit of PI3K (PIK3CA) and/or mutations of AKT1 itself. However, number and identity of downstream targets of activated PI3K/AKT pathway are poorly defined. To identify the genes that are targets of constitutive PI3K/AKT signalling in lung cancer cells, we performed a comparative transcriptomic analysis of human lung epithelial cells (BEAS-2B) expressing active mutant AKT1 (AKT1-E17K), active mutant PIK3CA (PIK3CA-E545K) or that are silenced for PTEN. For each sample, 500 ng of total RNA were used to synthesize biotinylated cRNA with Illumina RNA Amplification Kit (Ambion, Austin, TX). Synthesis was carried out according to the manufacturersâ instructions. From each sample, technical triplicates were produced and 750 ng cRNA were hybridized for 18h to Human HT-12_V3_0_R1 Expression BeadChips (Illumina, San Diego, CA). Hybridized chips were washed and stained with streptavidin-conjugated Cy3 (GE Healthcare, Milan, Italy). BeadChips were dried and scanned with an Illumina Bead Array Reader (Illumina).
2016-12-01 | E-MTAB-5286 | biostudies-arrayexpress
Project description:Introduction Basal-like (BLCs) and epidermal growth factor receptor 2 overexpressing (HER2+) carcinomas are the subgroups of breast cancers which have the more aggressive clinical behavior. In contrast to HER2+ carcinomas, no targeted therapy is currently available for the treatment of patients with BLCs. In order to discover potential therapeutic targets, we searched for deregulated signaling pathways in human BLCs. Methods In this study, we focused on the oncogenic phosphatidylinositol 3-kinase (PI3K) pathway in twelve BLCs, and compared it to a control series of eleven hormonal receptor negative- and grade III- matched HER2+ carcinomas. The two tumor populations were first characterized by immunohistochemistry and gene expression. The PI3K pathway was then investigated by gene copy-number analysis, gene expression profiling and at a proteomic level using reverse phase protein array technology and tissue microarray. The effects of PI3K inhibition pathway on proliferation and apoptosis was further analyzed in three human basal-like cell lines. Results The PI3K pathway was found to be activated in BLCs and up-regulated compared to HER2+ tumors as shown by a significantly increased activation of the downstream targets Akt and mTOR. BLCs expressed significantly lower levels of the tumor suppressor PTEN and PTEN levels correlated negatively in a significant manner with Akt activity within that population. PTEN protein expression correlated significantly with PTEN DNA copy number and more importantly, reduced PTEN DNA copy numbers were observed specifically in BLCs. Similarly to human samples, basal-like cell lines exhibited an activation of PI3K / Akt pathway and low/lack PTEN expression. Both PI3K and mTOR inhibitors led to basal-like cell growth arrest. However, apoptosis was observed specifically after PI3K inhibition.
2008-12-03 | GSE13787 | GEO