Ontology highlight
ABSTRACT:
PROVIDER: PRJNA545882 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:PAK4 suppresses RELB to prevent senescence-like growth arrest in breast cancer
| PRJNA449083 | ENA
Project description:Overcoming cellular growth restriction, including the evasion of cellular senescence, is a hallmark of cancer. We report that PAK4 is overexpressed in all human breast cancer subtypes and associated with poor patient outcome. In mice, MMTV-PAK4 overexpression promotes spontaneous mammary cancer, while PAK4 gene depletion delays MMTV-PyMT driven tumors. Importantly, PAK4 prevents senescence-like growth arrest in breast cancer cells in vitro, in vivo and ex vivo, but is not needed in non-immortalized cells, while PAK4 overexpression in untransformed human mammary epithelial cells abrogates H-Ras-V12-induced senescence. Mechanistically, a PAK4 – RELB - C/EBPa axis controls the senescence-like growth arrest and a PAK4 phosphorylation residue (RELB-Se151) is critical for RELB-DNA interaction, transcriptional activity and expression of the senescence regulator C/EBPa. These findings establish PAK4 as a promoter of breast cancer that can overcome oncogene-induced senescence and reveal a selective vulnerability of cancer to PAK4 inhibition.
2019-07-09 | GSE112817 | GEO
Project description:Estrogen receptor alpha (ERα) is highly expressed in most breast cancers. Consequently, ERα modulators, such as tamoxifen, are successful in breast cancer treatment, although tamoxifen resistance is commonly observed. While tamoxifen resistance may be caused by altered ERα signaling, the molecular mechanisms regulating ERα signaling and tamoxifen resistance are not entirely clear. Here, we found that PAK4 expression was consistently correlated to poor patient outcome in endocrine treated and tamoxifen-only treated breast cancer patients. Importantly, while PAK4 overexpression promoted tamoxifen resistance in MCF-7 human breast cancer cells, pharmacological treatment with a group II PAK (PAK4, 5, 6) inhibitor, GNE-2861, sensitized tamoxifen resistant MCF-7/LCC2 breast cancer cells to tamoxifen. Mechanistically, we identified a regulatory positive feedback loop, where ERα bound to the PAK4 gene, thereby promoting PAK4 expression, while PAK4 in turn stabilized the ERα protein, activated ERα transcriptional activity and ERα target gene expression. Further, PAK4 phosphorylated ERα-Ser305, a phosphorylation event needed for the PAK4 activation of ERα-dependent transcription. In conclusion, PAK4 may be a suitable target for perturbing ERα signaling and tamoxifen resistance in breast cancer patients.
2015-12-12 | GSE73320 | GEO
Project description:Using multi-omic analyses, we identified PAK4 (P21 (RAC1) Activated Kinase 4) amplification and overexpression of Kinase PAK4 in a subset of bladder cancers. We confirmed the role of PAK4 in bladder cancer cell proliferation and invasion by in vitro experiments. Furthermore, our studies showed that PAK4 inhibitor is effective in curtailing bladder cancer cell growth. In order to understand the effect of PAK4 inhibition and knockdown on bladder cancer transcriptome, we performed RNA-sequencing of PAK4 siRNA transfected and PAK4 inhibitor (PF-3758309) treated bladder cancer cells (VM-CUB1). Analyses led to identification of direct targets of PAK4 in bladder cancer and associated pathways.
2020-04-20 | GSE130455 | GEO
Project description:The cyclin-dependent kinase inhibitor p16INK4a (CDKN2A) is an important tumor-suppressor gene frequently inactivated in human tumors. p16 suppresses the development of cancer by triggering an irreversible arrest of cell proliferation termed cellular senescence. Here, we describe another anti-oncogenic function of p16 in addition to its ability to halt cell cycle progression. We show that transient expression of p16 stably represses the hTERT gene, encoding the catalytic subunit of telomerase, in both normal and malignant breast epithelial cells. Short-term p16 expression increases the amount of histone H3 trimethylated on lysine 27 (H3K27) bound to the hTERT promoter, resulting in transcriptional silencing, likely mediated by polycomb complexes. Our results indicate that transient p16 exposure may prevent malignant progression in dividing cells by irreversible repression of genes, such as hTERT, whose activity is necessary for extensive self-renewal. 27 samples were analyzed to study three histone modifications (H3K4me3, H3K9me3, H3K27me3) in three different cell lines. Each combination of histone modification and cell line had three biological replicates (A,B,C).
2010-05-19 | E-GEOD-14436 | biostudies-arrayexpress
Project description:The cyclin-dependent kinase inhibitor p16INK4a (CDKN2A) is an important tumor-suppressor gene frequently inactivated in human tumors. p16 suppresses the development of cancer by triggering an irreversible arrest of cell proliferation termed cellular senescence. Here, we describe another anti-oncogenic function of p16 in addition to its ability to halt cell cycle progression. We show that transient expression of p16 stably represses the hTERT gene, encoding the catalytic subunit of telomerase, in both normal and malignant breast epithelial cells. Short-term p16 expression increases the amount of histone H3 trimethylated on lysine 27 (H3K27) bound to the hTERT promoter, resulting in transcriptional silencing, likely mediated by polycomb complexes. Our results indicate that transient p16 exposure may prevent malignant progression in dividing cells by irreversible repression of genes, such as hTERT, whose activity is necessary for extensive self-renewal.
2009-12-01 | GSE14436 | GEO
Project description:Cellular senescence is a stable cell growth arrest that is implicated in tissue aging and cancer. Senescent cells are characterized by an upregulation of proinflammatory and immunosuppressive cytokines and chemokines, which is termed as senescence-associated secretory phenotype (SASP). NAD+ metabolism plays a critical role in both tissue aging and cancer. However, the role of NAD+ metabolism in regulating the SASP is not well understood. Here we show that nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme of the NAD+ salvage pathway, governs the strengths of proinflammatory SASP during senescence. In contrast to downregulation of NAMPT during replicative senescence, NAMPT is upregulated during oncogene-induced senescence. NAMPT selectively regulates proinflammatory, but not immunosuppressive, SASP. NAMPT is regulated by HMGA1 through a distal enhancer element during senescence. HMGA1/NAMPT/NAD+ signaling axis promotes proinflammatory SASP through enhancing glycolysis and mitochondria respiration. Mechanistically, HMGA1/NAMPT promotes proinflammatory SASP through NAD+-mediated suppression of AMPK kinase, which suppresses p53-mediated inhibition of p38MAPK to enhance NFb activity. SASP regulation by NAD+ metabolism is independent of senescence-associated cell growth arrest. An increase in NAD+ levels is sufficient to convert SASP from low to high levels during replicative senescence. Together, we conclude that NAD+ metabolism governs the strengths of proinflammatory SASP. Given the tumor promoting effects of proinflammatory SASP, our results suggest that anti-ageing dietary NAD+ augmentation should be administered with precision.
2019-03-14 | GSE111841 | GEO
Project description:During this last decade the development of pro-senescence therapies has become an attractive strategy as cellular senescence acts as a barrier against tumour progression. In this context, CDK4/6 inhibitors induce senescence and reduce tumour growth in breast cancer patients. However, even though cancer cells are arrested after CDK4/6 inhibitor treatment, genes regulating senescence in this context are still unknown limiting their anti-tumour activity. Here, using a functional genome wide CRISPR/Cas9 genetic screen we found several genes that participate in the proliferation arrest induced by CDK4/6 inhibitors. We find that downregulation of the coagulation factor IX (F9) using sgRNA and shRNA prevents the cell cycle arrest and senescent-like phenotype induced in MCF7 breast tumour cells upon Palbociclib treatment. These results were confirmed using another breast cancer cell line, T47D, and with an alternative CDK4/6 inhibitor, Abemaciclib, and further tested in a panel of 22 cancer cells. While F9 knockout prevents the induction of senescence, treatment with a recombinant F9 protein was sufficient to induce a cell cycle arrest and senescence-like state in MCF7 tumour cells. Besides, endogenous F9 is upregulated in different human primary cells cultures undergoing senescence. Importantly, bioinformatics analysis of cancer datasets suggest a role for F9 in human tumours. Altogether, these data collectively propose key genes involved in CDK4/6 inhibitor response that will be useful to design new therapeutic strategies in personalized medicine in order to increase their efficiency, stratify patients and avoid drug resistance.
2022-03-31 | GSE192525 | GEO
Project description:DallePazze2014 - Cellular senescene-induced
mitochondrial dysfunction
This model is described in the article:
Dynamic modelling of
pathways to cellular senescence reveals strategies for targeted
interventions.
Dalle Pezze P, Nelson G, Otten EG,
Korolchuk VI, Kirkwood TB, von Zglinicki T, Shanley DP.
PLoS Comput. Biol. 2014 Aug; 10(8):
e1003728
Abstract:
Cellular senescence, a state of irreversible cell cycle
arrest, is thought to help protect an organism from cancer, yet
also contributes to ageing. The changes which occur in
senescence are controlled by networks of multiple signalling
and feedback pathways at the cellular level, and the interplay
between these is difficult to predict and understand. To
unravel the intrinsic challenges of understanding such a highly
networked system, we have taken a systems biology approach to
cellular senescence. We report a detailed analysis of
senescence signalling via DNA damage, insulin-TOR, FoxO3a
transcription factors, oxidative stress response, mitochondrial
regulation and mitophagy. We show in silico and in vitro that
inhibition of reactive oxygen species can prevent loss of
mitochondrial membrane potential, whilst inhibition of mTOR
shows a partial rescue of mitochondrial mass changes during
establishment of senescence. Dual inhibition of ROS and mTOR in
vitro confirmed computational model predictions that it was
possible to further reduce senescence-induced mitochondrial
dysfunction and DNA double-strand breaks. However, these
interventions were unable to abrogate the senescence-induced
mitochondrial dysfunction completely, and we identified
decreased mitochondrial fission as the potential driving force
for increased mitochondrial mass via prevention of mitophagy.
Dynamic sensitivity analysis of the model showed the network
stabilised at a new late state of cellular senescence. This was
characterised by poor network sensitivity, high signalling
noise, low cellular energy, high inflammation and permanent
cell cycle arrest suggesting an unsatisfactory outcome for
treatments aiming to delay or reverse cellular senescence at
late time points. Combinatorial targeted interventions are
therefore possible for intervening in the cellular pathway to
senescence, but in the cases identified here, are only capable
of delaying senescence onset.
This model is hosted on
BioModels Database
and identified by:
BIOMD0000000582.
To cite BioModels Database, please use:
BioModels Database:
An enhanced, curated and annotated resource for published
quantitative kinetic models.
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.
2015-08-12 | BIOMD0000000582 | BioModels
Project description:Immune checkpoint bloackade (ICB)-based or natural cancer immune responses largely eliminate tumours. Yet, they require additional mechanisms to arrest those cancer cells that are not rejected. Cytokine-induced senescence (CIS) can stably arrest cancer cells, suggesting that interferon-dependent induction of senescence-inducing cell cycle regulators is needed to control those cancer cells that escape from killing. Here we report in two different cancers sensitive to T cell-mediated rejection, we show that deletion of the senescence-inducing cell cycle regulators p16Ink4a/p19Arf (Cdkn2a) or p21Cip1 (Cdkn1a) in the tumour cells abrogated both, the natural and the ICB-induced cancer immune control. Also in humans, melanoma metastases that progressed rapidly during ICB have losses of senescence-inducing genes and amplifications of senescence inhibitors. Metastatic cells also resist CIS. Such genetic and functional alterations are infrequent in metastatic melanomas regressing during ICB. Thus, activation of tumour-intrinsic, senescence-inducing cell cycle regulators is required to stably arrest those cancer cells that escape from eradication.
| EGAS00001004151 | EGA