Browse
Submit Data
Databases
API
Help

Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

50 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Suppression of BRCA1 sensitizes to proteasome inhibitors in DNA repair-independent manner.

ABSTRACT: Germline and somatic mutations in BRCA1predispose to breast cancer. We found that proteasome inhibitors can selectively kill BRCA1-depleted cells. The toxic response involves a deregulation of the G1/S cell cycle checkpoint via hyperphosphorylation of RB1, 53BP1-mediated arrest at G2/M checkpoint, and ERN1-mediated unfolded protein response, culminating in a TNF receptor-mediated apoptosis. The study new unexpected molecular functions for BRCA1 protein and opens a novel possibility for the treatment of BRCA1-deficient cancers. We used microarrays to detail the global programme of gene expression underlying the response of BRCA1-deficient cells to proteasome inhibitor bortezomib. We aimed to identify genes that are strongly up- or down-regulated with a combination of BRCA1 knockdown and proteasome inhibition, but none of these treatments alone before the onset of apoptosis. HeLa and U2OS cells were transfected either with a non-targeting or anti-BRCA1 siRNAs (siControl or siBRCA1, respectively), treated with bortezomib for 8 hours, after which RNA was extracted for hybridization on Affymetrix microarray. The following treatments have been performed: (T1) siControl; (T2) siControl + 20 nM bortezomib for 8h; (T3) siBRCA1; (T4) siBRCA1 + 20 nM bortezomib for 8h. All samples were used without replicas. However, all genes showing inconsistent expression pattern between the two cell lines were excluded from further consideration. Selected candidate genes were subject to validation by qRT-PCR.

ORGANISM(S): Homo sapiens

SUBMITTER: Dario Greco

PROVIDER: E-GEOD-56280 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Json Xml

Similar Datasets

Suppression of BRCA1 sensitizes to proteasome inhibitors in DNA repair-independent manner.

Project description:Germline and somatic mutations in BRCA1predispose to breast cancer. We found that proteasome inhibitors can selectively kill BRCA1-depleted cells. The toxic response involves a deregulation of the G1/S cell cycle checkpoint via hyperphosphorylation of RB1, 53BP1-mediated arrest at G2/M checkpoint, and ERN1-mediated unfolded protein response, culminating in a TNF receptor-mediated apoptosis. The study new unexpected molecular functions for BRCA1 protein and opens a novel possibility for the treatment of BRCA1-deficient cancers. We used microarrays to detail the global programme of gene expression underlying the response of BRCA1-deficient cells to proteasome inhibitor bortezomib.

2015-01-01 | GSE56280 | GEO

Proteasome inhibition sensitizes anaplastic Wilms tumor to actinomycin D

Project description:Wilms tumor is the most common kidney cancer in children, and anaplastic Wilms tumor is the most chemoresistant histological subtype. Here we explore how anaplastic Wilms tumor cells evade the common chemotherapeutic drug actinomycin D, which inhibits ribosomal biogenesis. We found that, when ribosomal capacity is limited by actinomycin D treatment, anaplastic Wilms tumor cells preferentially translate proteasome components and upregulate proteasome activity. Accordingly, increased proteasome levels are associated with anaplastic histology and with worse prognosis in Wilms tumor. Lastly, we show that the proteasome inhibitor bortezomib sensitizes cells to actinomycin D treatment both in vitro and in vivo.

2024-06-20 | GSE270330 | GEO

Cytotoxic effects of Bortezomib in Myelodysplastic syndrome/Acute Myeloid Leukemia depend on autophagy-mediated lysosomal degradation of TRAF6 and repression of PSMA1

Project description:Bortezomib (Velcade©) is widely used for the treatment of various human cancers, however, its mechanisms of action are not fully understood, particularly in myeloid malignancies. Bortezomib is a selective and reversible inhibitor of the proteasome. Paradoxically, we find that Bortezomib induces proteasome-independent degradation of TRAF6 protein, but not mRNA, in Myelodysplastic syndrome (MDS) and Acute Myeloid Leukemia (AML) cell lines and primary cells. The reduction in TRAF6 protein coincides with Bortezomib-induced autophagy, and subsequently with apoptosis in MDS/AML cells. RNAi-mediated knockdown of TRAF6 sensitized Bortezomib-sensitive and -resistant cell lines, underscoring the importance of TRAF6 in Bortezomib-induced cytotoxicity. Bortezomib-resistant cells expressing an shRNA targeting TRAF6 were resensitized to the cytotoxic effects of Bortezomib due to down-regulation of the proteasomal subunit alpha-1 (PSMA1). To uncover the molecular consequences following loss of TRAF6 in MDS/AML cells, we applied gene expression profiling and identified an apoptosis gene signature. Knockdown of TRAF6 in MDS/AML cell lines or patient samples resulted in rapid apoptosis and impaired malignant hematopoietic stem/progenitor function. In summary, we describe novel mechanisms by which TRAF6 is regulated through Bortezomib/autophagy-mediated degradation and by which it alters MDS/AML sensitivity to Bortezomib by controlling PSMA1 expression.

2012-06-15 | GSE38519 | GEO

Cytotoxic effects of Bortezomib in Myelodysplastic syndrome/Acute Myeloid Leukemia depend on autophagy-mediated lysosomal degradation of TRAF6 and repression of PSMA1

Project description:Bortezomib (VelcadeM-BM-)) is widely used for the treatment of various human cancers, however, its mechanisms of action are not fully understood, particularly in myeloid malignancies. Bortezomib is a selective and reversible inhibitor of the proteasome. Paradoxically, we find that Bortezomib induces proteasome-independent degradation of TRAF6 protein, but not mRNA, in Myelodysplastic syndrome (MDS) and Acute Myeloid Leukemia (AML) cell lines and primary cells. The reduction in TRAF6 protein coincides with Bortezomib-induced autophagy, and subsequently with apoptosis in MDS/AML cells. RNAi-mediated knockdown of TRAF6 sensitized Bortezomib-sensitive and -resistant cell lines, underscoring the importance of TRAF6 in Bortezomib-induced cytotoxicity. Bortezomib-resistant cells expressing an shRNA targeting TRAF6 were resensitized to the cytotoxic effects of Bortezomib due to down-regulation of the proteasomal subunit alpha-1 (PSMA1). To uncover the molecular consequences following loss of TRAF6 in MDS/AML cells, we applied gene expression profiling and identified an apoptosis gene signature. Knockdown of TRAF6 in MDS/AML cell lines or patient samples resulted in rapid apoptosis and impaired malignant hematopoietic stem/progenitor function. In summary, we describe novel mechanisms by which TRAF6 is regulated through Bortezomib/autophagy-mediated degradation and by which it alters MDS/AML sensitivity to Bortezomib by controlling PSMA1 expression. TF-1 cells were transduced with lentivirus encoding shRNA targeting human TRAF6 and a negative control (pLKO) for 2.5 days. GFP positive cells were sorted for RNA exctration, labeling, and hybridization. A total of four samples were included, and two groups are assigned. Two replicates are for each group. Comparison comprises mRNA expression profile of TRAF6 knockdown (shT6) v.s. control vector (pLKO).

2012-06-14 | E-GEOD-38519 | biostudies-arrayexpress

Tight Junction Protein 1 is a Modulator and Biomarker of Proteasome Inhibitor Sensitivity in Multiple Myeloma

Project description:Proteasome inhibitors are important chemotherapeutics in the treatment of multiple myeloma, but they are currently used empirically as no markers of sensitivity have been validated. We have identified expression of tight junction protein (TJP) 1 as being associated with sensitivity of plasma cells in vitro and in vivo to proteasome inhibitors. TJP1 suppressed expression of genes in the major histocompatibility class II region, including two catalytically active immunoproteasome subunits, thereby decreasing proteasome activity, a critical determinant of proteasome inhibitor sensitivity. This occurred through suppression by TJP1 of signaling through the epidermal growth factor receptor/Janus kinase 1/signal transducer and activator of transcription 3 pathway. In the clinic, high TJP1 expression in myeloma patients was associated with a significantly higher likelihood of responding to bortezomib, and with a longer time-to-progression after treatment. Taken together, these data support the use of TJP1 as a biomarker of sensitivity and resistance to proteasome inhibitors. To further elucidate mechanisms of bortezomib resistance, we developed human-derived multiple myeloma cell lines with a 4-fold or greater resistance to bortezomib. Then total RNA for bortezomib resistant (BR) and wild type (WT) was extracted and used for comparison by gene expression profiling.

2015-12-31 | E-GEOD-52369 | biostudies-arrayexpress

Analysis of transcriptional changes associated to proteasome inhibition in HCT-116 human colorectal cancer cells

Project description:The proteasome is a central player in several cellular aspects, such as homeostasis, cell cycle progression, and even transcription. Recent work has shown that proteasome inhibition promotes pervasive epigenetic changes in the human genome. However, the impact of proteasome inhibitors on ncRNAs is poorly understood. We treated control (asynchronous) or G2-synchronized HCT-116 human colon cancer cells with the proteasome inhibitors MG132 and bortezomib and performed total RNA-seq. We also included cells treated simultaneously with MG132 and the RNA-pol II inhibitor α-amanitin to determine the transcriptional changes mediated by such RNA polymerase. We report that MG132 and bortezomib impact similar regions of the genome. A remarkable transcriptional activation was observed in centromeres and pericentromers, especially in α-satellite repeats. RNAs emanating from these regions are known to participate in chromosome segregation. Our results suggest that the proteasome can regulate mitotic progression, not only by participating in protein turnover, but also by regulating ncRNAs.

2021-12-14 | GSE165325 | GEO

Molecular targets of bortezomib on adult T-cell leukemia cells

Project description:BACKGROUND: The molecular mechanism of proteasome inhibitor-mediated anti-cancer activity has been logically hypothesized that the major pathway is inhibition of nuclear factor kappa-B (NF-kB) cascades, however, the precise mechanism is still unclear. Adult T-cell leukemia (ATL) is a fatal neoplasia derived from HTLV-1 infected T lymphocytes exhibiting constitutive activation of NF-kB. AIM: To elucidate the complex molecular mechanism of anti-tumor effect of the proteasome inhibitor, bortezomib in ATL cells, we attempted to perform network-based gene expression profiling. METHODS and RESULTS: Assessment of gene regulation by microarray analysis revealed that down-regulation of genes involved in anti-apoptosis (i.e., BCL2, and IAP5), up-regulation of genes related with apoptosis (i.e., FAF1), heat shock proteins (i.e., HSPA, HSPCA), and oxygen stress (i.e., heme oxygenase-1: HMOX-1). Gene network analysis employing the Bayesian statistical framework also suggests that HMOX-1 which is known as an inducer of reactive oxygen species (ROS), as well as SPARC play an important role in bortezomib-treated ATL cells. The HMOX-1 inhibitor, ZnPP, in addition to bortezomib partially inhibited the apoptotic effect of bortezomib on TaY cells. CONCLUSION: Our results suggest that in addition to the inhibition of NF-kB, bortezomib activated ROS pathway through HMOX-1, and SPARC may participate bortezomib-induced apoptosis, providing novel insight into the bortezomib mediated anti-tumor activity in ATL cells. Keywords: dose response and time course

2007-10-09 | GSE5794 | GEO

Cellular response to proteasome inhibition by Bortezomib

Project description:Analysis of the coordinated transcriptional reponse to proteasome inhibition mRNA profiles of NIH3T3 cells which stably expressing DD-sfGFP were generated by deep sequencing using Illumina HiSeq. The samples were collected from indicated timepoints after exposed to proteasome inhibition by Bortezomib.

2015-09-04 | E-GEOD-71145 | biostudies-arrayexpress

Mus musculus

Project description:Cellular response to proteasome inhibition by Bortezomib

| PRJNA290443 | ENA

ERAD inhibitors integrate ER stress with an epigenetic mechanism to activate BH3 only protein NOXA in cancer cells

Project description:The ubiquitin-proteasome system (UPS) has recently emerged as a major target for drug development in cancer therapy. The proteasome inhibitor bortezomib has clinical activity in multiple myeloma and mantle cell lymphoma. Here we report that Eeyarestatin I (EerI), a chemical inhibitor that blocks ER-associated protein degradation (ERAD), has anti-tumor and biologic activities similar to bortezomib, and can synergize with bortezomib. Like bortezomib, EerI-induced cytotoxicity requires the upregulation of the BH3 only pro-apoptotic protein NOXA. We further demonstrate that both EerI and bortezomib activate NOXA via an unanticipated mechanism that requires cooperation between two processes: First, these agents elicit an integrated stress response program at the ER to activate the CREB/ATF transcription factors ATF3 and ATF4. We show that ATF3 and ATF4 form a complex capable of binding to the NOXA promoter, which is required for NOXA activation. Second, EerI and bortezomib also block ubiquitination of histone H2A to relieve its inhibition on NOXA transcription. Our results identify a class of anti-cancer agents that integrate ER stress response with an epigenetic mechanism to induce cell death.

2009-02-20 | GSE14003 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data