RNA seq of mammary epithelial cells with loss-of-function Pten mutations
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE140289 | GEO | 2020/10/16
REPOSITORIES: GEO
Similar Datasets
Project description:The PTEN tumor suppressor controls cell death and survival by regulating functions of various molecular targets. Whilst the role of PTEN lipid-phosphatase activity on PtdIns(3,4,5)P3 and inhibition of PI3K pathway is well characterized, the biological relevance of PTEN protein-phosphatase activity remains undefined. Using knock-in (KI) mice harbouring cancer-associated and functionally relevant missense mutations, we show that although loss of PTEN lipid-phosphatase function cooperates with oncogenic PI3K to promote rapid mammary tumorigenesis, the additional loss of PTEN protein-phosphatase activity triggered an extensive cell death response evident in early and advanced mammary tumors. Omics and drug-targeting studies revealed that PI3Ks act to reduce glucocorticoid receptor (GR) levels, which are rescued by loss of PTEN protein-phosphatase activity to restrain cell survival. The dual regulation of GR by PI3K and PTEN functions as a rheostat that can be exploited for the treatment of PTEN-loss driven cancers.
2020-10-15 | PXD016184 | Pride
Project description:Phosphatase activities on PI(3,4,5)P3 and
PI(3,4)P2
This model describes the action of various phosphatases on
PI(3,4,5)P3 and PI(3,4)P2, in response to a stimulation by EGF. It
contains boolean switches to simulate knock-down and knock-out of
phosphatases as well as inhibition of PI3 kinase.
This model is described in the article:
PTEN Regulates PI(3,4)P2
Signaling Downstream of Class I PI3K
Mouhannad Malek, Anna Kielkowska,
Tamara Chessa, Karen E. Anderson, David Barneda, P?nar Pir,
Hiroki Nakanishi, Satoshi Eguchi, Atsushi Koizumi, Junko Sasaki,
Véronique Juvin, Vladimir Y. Kiselev, Izabella Niewczas,
Alexander Gray, Alexandre Valayer, Dominik Spensberger, Marine
Imbert, Sergio Felisbino, Tomonori Habuchi, Soren Beinke, Sabina
Cosulich, Nicolas Le Novère, Takehiko Sasaki, Jonathan
Clark, Phillip T. Hawkins and Len R. Stephens
Molecular Cell
Abstract:
The PI3K signaling pathway regulates cell growth and
movement and is heavily mutated in cancer. Class I PI3Ks
synthesize the lipid messenger PI(3,4,5)P3. PI(3,4,5)P3 can be
dephosphorylated by 3- or 5-phosphatases, the latter producing
PI(3,4)P2. The PTEN tumor suppressor is thought to function
primarily as a PI(3,4,5)P3 3-phosphatase, limiting activation
of this pathway. Here we show that PTEN also functions as a
PI(3,4)P2 3-phosphatase, both in vitro and in vivo. PTEN is a
major PI(3,4)P2 phosphatase in Mcf10a cytosol, and loss of PTEN
and INPP4B, a known PI(3,4)P2 4-phosphatase, leads to
synergistic accumulation of PI(3,4)P2, which correlated with
increased invadopodia in epidermal growth factor
(EGF)-stimulated cells. PTEN deletion increased PI(3,4)P2
levels in a mouse model of prostate cancer, and it inversely
correlated with PI(3,4)P2 levels across several EGF-stimulated
prostate and breast cancer lines. These results point to a role
for PI(3,4)P2 in the phenotype caused by loss-of-function
mutations or deletions in PTEN.
This model is hosted on
BioModels Database
and identified by:
MODEL1704190000.
To cite BioModels Database, please use:
Chelliah V et al. BioModels: ten-year
anniversary. Nucl. Acids Res. 2015, 43(Database
issue):D542-8.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
| MODEL1704190000 | BioModels
Project description:Analysis of murine model of T cell acute lymphoblastic leukemia (T-ALL) caused by deletion of phosphatase and tensin homologue deleted on chromosome 10 (PTEN) reveals that primary T-ALL cells have high transport rates for multiple nutrients. In particular, high levels of leucine transport in T-ALL fuels mammalian target of rapamycin complex 1 (mTORC1) activity which then sustains expression of hypoxia inducible factor-1a (HIF1a) and c-Myc, the drivers of glucose transport. A key finding is that PTEN deletion and phosphatidylinositol (3,4,5)-trisphosphate (PtdIns(3,4,5)P3) accumulation is insufficient to initiate leucine uptake, mTORC1 activity, HIF1a or c-Myc expression in T cells and hence cannot drive T-ALL metabolic reprogramming. Instead, a key regulator for leucine transport in T-ALL is identified as NOTCH. Mass spectrometry based proteomics identifies SLC7A5 as the dominant System L-amino acid transporter in primary PTEN-/- T-ALL cells. Importantly, expression of SLC7A5 is critical for the malignant transformation induced by PTEN deletion. These data highlight the importance of regulated amino acid transport for T cell malignancies and how a single amino acid transporter can play a key role.
2018-10-08 | PXD006209 | Pride
Project description:The PTEN:P-Rex2 complex is a commonly mutated signaling nodes in metastatic cancer. The dual-specificity phosphatase PTEN canonically functions as a tumour suppressor by hydrolysing PI(3,4,5)P3 to PI(4,5)P2 to inhibit PI3K-AKT signaling. P-Rex2 is a RhoGTPase guanine nucleotide exchange factor activated by both Gβγ and PI(3,4,5)P3 downstream of G protein-coupled receptor and receptor tyrosine kinase signaling. Assembly of the PTEN:P-Rex2 complex inhibits the activity of both proteins, and its dysregulation can drive PI3K-AKT signaling and cell proliferation. However, structural insights into both PTEN:P-Rex2 complex assembly and its dysregulation by cancer-associated mutations remain limited. Here, using crosslinking mass spectrometry and functional studies, we provide mechanistic insights into PTEN:P-Rex2 complex assembly and co-inhibition. PTEN is anchored to P-Rex2 by interactions between the PTEN C-terminal tail PDZ-interacting motif and the second PDZ domain of P-Rex2. This interaction bridges PTEN across the P-Rex2 surface, occluding PI(3,4,5)P3 hydrolysis. Conversely, PTEN both allosterically promotes an autoinhibited P-Rex2 conformation and occludes Gβγ binding. These insights allow us to define a new gain-of-function class of cancer mutations within the PTEN:P-Rex2 interface that uncouples PTEN inhibition of Rac1 signaling. In addition, we observe synergy between PTEN deactivating and P-Rex2 truncation mutations that combine to drive Rac1 activation to a greater extent than either single mutation alone.
2022-08-12 | PXD021126 | Pride
Project description:The PIP3/PI3K network is a central regulator of metabolism and is frequently activated in cancer, commonly by loss of the PIP3/PI(3,4)P2-phosphatase, PTEN. Despite huge investment, the drivers of the PI3K network in normal tissues and how they adapt to overactivation are unclear. We find that in healthy mouse prostate PI3K activity is driven by RTK/IRS signalling and constrained by pathway-feedback. In the absence of PTEN, the network is dramatically remodelled. A poorly understood, YXXM- and PIP3/PI(3,4)P2-binding PH domain-containing, adaptor, PLEKHS1, became the dominant activator and was required to sustain PIP3, AKT-phosphorylation and growth in PTEN-null prostate. This was because PLEKHS1 evaded pathway-feedback and experienced enhanced PI3K- and SRC-family kinase-dependent phosphorylation of Y258XXM, eliciting PI3K-activation. hPLEKHS1-mRNA and activating-Y419-phosphorylation of hSRC correlated with PI3K-pathway activity in human prostate cancers. We propose that in PTEN-null cells, receptor-independent, SRC-dependent tyrosine-phosphorylation of PLEKHS1 creates positive-feedback that escapes homeostasis, drives PIP3-signalling and supports tumour progression.
2023-08-23 | PXD043239 | Pride
Project description:Dysregulation of the PI3K/AKT pathway is a common occurrence in ovarian carcinomas. Loss of the tumour suppressor PTEN in high-grade serous ovarian carcinoma (HGSOC) is associated with a patient subgroup with poor prognosis. The cellular mechanisms of how PTEN loss contributes to HGSOC are largely unknown. We utilise long-term time-lapse imaging of HGSOC spheroids coupled to a machine learning approach to classify the phenotype of PTEN loss. PTEN deficiency does not affect proliferation but rather induces PI(3,4,5)P3-rich and -dependent membrane protrusions into the extracellular matrix (ECM), resulting in a collective invasion phenotype. We identify the small GTPase ARF6 as a crucial vulnerability upon PTEN loss. Through a functional proteomic CRISPR screen of ARF6 interactors, we identify the ARF GTPase-activating protein (GAP) AGAP1 and the ECM receptor β1-integrin as key ARF6 interactors regulating the PTEN loss-associated invasion phenotype. ARF6 functions to promote invasion by controlling the recycling of internalised, active β1-integrin complexes to maintain invasive activity into the ECM. The expression of the ARF6-centred complex in HGSOC patients is inversely associated with outcome, allowing identification of patient groups with improved versus poor outcome. ARF6 may represent a new therapeutic vulnerability in PTEN-depleted HGSOC tumours.
2023-07-11 | PXD038305 | Pride
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:Polyphosphoinositides (PPIn) play essential functions as lipid signalling molecules and many of their functions have been elucidated in the cytoplasm. However, PPIns are also intranuclear where they contribute to chromatin remodelling, transcription and mRNA splicing. The PPIn, phosphatidylinositol 3,4,5-triphosphate (PtdIns(3,4,5)P3) has been mapped to the nucleus and nucleoli but its role remains unclear in this subcellular compartment. To gain further insights into the nuclear functions of PtdIns(3,4,5)P3, we applied a previously developed quantitative mass spectrometry-based approach to identify the targets of PtdIns(3,4,5)P3 from isolated nuclei. We identified 179 potential PtdIns(3,4,5)P3-interacting proteins and gene ontology analysis for the biological functions of this dataset revealed an enrichment in RNA processing/splicing, cytokinesis, protein folding and DNA repair. Interestingly, about half of these interactors were common to nucleolar protein datasets, some of which had dual functions in rRNA transcription and DNA repair, including Poly(ADP-Ribose) Polymerase 1 (PARP1),. PARP1 was found to interact directly with PPIns and to co-localise with PtdIns(3,4,5)P3 in the nucleolus. Focusing on another factor involved in RNA processing, heterogeneous nuclear ribonucleoprotein U (hnRNPU/SAF-A) was also identified and validated as a direct PPIn-interacting protein. Deletion of the polybasic motif in its DNA binding domain prevented PPIn interaction. In conclusion, the PtdIns(3,4,5)P3 interactome reported here identified several nucleolar proteins and splicing factors and further pointed to roles for this lipid in these processes.
2021-06-28 | PXD020870 | Pride
Project description:Diffuse large B-cell lymphoma (DLBCL) represents a heterogeneous diagnostic category with distinct molecular subtypes that can be deM-oM-,M-^Aned by gene expression proM-oM-,M-^Aling. However, even within these deM-oM-,M-^Aned subtypes, heterogeneity prevails. To further elucidate the pathogenesis of these entities, we determined the expression of the tumor suppressor phosphatase and tensin homolog (PTEN) in 248 primary DLBCL patient samples. These analyses revealed that loss of PTEN was detectable in 55% of germinal center B-cell-like (GCB) DLBCLs, whereas this abnormality was found in only 14% of non-GCB DLBCL patient samples. In GCB DLBCL, the PTEN status was inversely correlated with activation of the oncogenic PI3K/ protein kinase B (AKT) pathway in both DLBCL cell lines and primary patient samples. Reexpression of PTEN induced cytotox- icity in PTEN-deM-oM-,M-^Acient GCB DLBCL cell line models by inhibiting PI3K/AKT signaling, indicating an addiction to this pathway in this subset of GCB DLBCLs. PI3K/AKT inhibition induced down-regulation of the transcription factor MYC. Reexpression of MYC rescued GCB DLBCL cells from PTEN-induced toxicity, identifying a regulatory mechanism of MYC expression in DLBCL. Finally, pharmacologic PI3K inhibition resulted in toxicity selectively in PTEN-deM-oM-,M-^Acient GCB DLBCL lines. Collectively, our results indicate that PTEN loss deM-oM-,M-^Anes a PI3K/ AKT-dependent GCB DLBCL subtype that is addicted to PI3K and MYC signaling and suggest that pharmacologic inhibition of PI3K might represent a promising therapeutic approach in these lymphomas. This GEO dataset is comprised of a) GEP measurements for 34 primary DLBCL patient samples plus two reference samples, b) 8 paired GEP measurements of the HT DLBCL cell line and c) aCGH measurements for two DLBCL cell lines in addition to previously published cell lines in GSE43272 (i.e., Sample GSM1059798). All of these data were used in the paper cited below.
2013-07-09 | E-GEOD-45495 | biostudies-arrayexpress