Modulator of Apoptosis 1 (MOAP-1) is a highly regulated tumor suppressor protein
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE43990 | GEO | 2015/11/02
SECONDARY ACCESSION(S): PRJNA188305
REPOSITORIES: GEO
Similar Datasets
Project description:Modulator of apoptosis 1 (MOAP-1) is a BH3-like protein that plays key roles in both the intrinsic and extrinsic modes of cell death or apoptosis. It is an integral partner to the tumor suppressor Ras association domain family 1A (RASSF1A) and functions to activate the Bcl-2 family pro-apoptotic protein Bax. Although RASSF1A is now considered a bona fide tumor suppressor protein, the role of MOAP-1 as a tumor suppressor is yet to be determined. In this study, we present several lines of evidence from cancer databases, immnoblotting of cancer cells, proliferation and xenograft assays to demonstrate the role of MOAP-1 as a tumor suppressor. MOAP-1 overexpressed tumors display upregulation of multiple genes including several pro-apoptotic members that may influence the role of MOAP-1 in cell death. Frequent loss of MOAP-1 expression, in at least some cancers, appears to be attributed to enhanced proteasomal degradation. The loss of RASSF1A is an early marker of tumorigenesis and we speculate that the additional loss of function of MOAP-1 may be a second âhitâ to functionally compromise the RASSF1A/MOAP-1 death receptor dependent pathway and drive tumorigensis. RNA was isolated mouse xenographs generated with the HCT116 cell line transfected with wild type Myc-tagged MOAP-1, empty Vector or the Myc-tagged MOAP-1 mutants K278R or K264R in triplicate. Pairwise gene expression differences were compared the two samples. Features selected had more than 1.5-fold up-or down-regulated (P values of >05, unpaired Studentâs t-test).
2015-11-02 | E-GEOD-43990 | biostudies-arrayexpress
Project description:The decision of metazoan cells to live or undergo programmed cell death hinges on the balance between the levels of pro- versus anti-apoptotic gene products. The general RNA polymerase II (Pol II) transcription factor, TFIID, plays a central role in the regulation of gene expression through its core promoter recognition and co-activator functions. The core TFIID subunit TAF6 is a co-activator for the pro-apoptotic p53 tumour suppressor protein. Our previous studies identified a specialized isoform of TAF6, termed TAF6 that can specifically be induced in apoptosis. To elucidate the impact of TAF6 on gene expression and cell death, we employed modified antisense oligonucleotides to enforce expression of endogenous TAF6. The induction of endogenous TAF6 triggered apoptosis in several cancer cell lines. Importantly, TAF6 also induces apoptosis in tumor cell lines devoid of p53, placing TAF6 function downstream of p53. Microarray experiments uncovered a TAF6-induced transcriptome landscape displaying enhanced expression of genes of the Notch, oxidative stress, integrin, p53 and apoptosis pathways. Our data show that the TAF6 pathway is a pivotal signalling nexus that controls pro-apoptotic gene expression programs. Keywords: Treatment with splice site switching antisense oligonucleotides, induction of apoptosis Biological triplicates, 3 conditions: control oligonucleotide, Taf6 oligonucleotide, specificity control Bcl-x oligonucleotide
2010-11-27 | E-GEOD-8752 | biostudies-arrayexpress
Project description:Metastatic malignant melanoma is the deadliest skin cancer type, and it is characterized by its high resistance to apoptosis. The main driving mutations in melanoma cause hyperactivation of genes within the ERK pathway, with BRAF mutations being the most frequent ones, followed by NRAS, NF1 and MEK mutations. Increasing evidence shows that the MST2/Hippo pathway is also deregulated in this cancer type. While mutations are rare, MST2/Hippo pathway core proteins expression levels are often dysregulated in melanoma. The expression of the tumour suppressor RASSF1A, a bona fide activator of the pro-apoptotic MST2 pathway, is silenced by promoter methylation in over half of melanomas and correlates with poor prognosis. Here, using mass spectrometry-based interaction proteomics we identified Second Mitochondria-derived Activator of Caspases (SMAC) as a novel LATS1 interactor. We show that RASSF1A-dependent activation of the pro-apoptotic MST2 pathway promotes LATS1-SMAC interaction and negatively regulates the anti-apoptotic signal mediated by the members of the IAP family. Moreover, proteomic experiments identified a common cluster of the apoptotic regulator that bind to SMAC and LATS1. Mechanistic analysis show that the LATS1-SMAC complex promotes XIAP ubiquitination and its subsequent degradation which ultimately results apoptosis. Importantly, we show that the oncogenic BRAFV600E mutant prevents the pro-apoptotic signal mediated by the LAST1-SMAC complex while treatment of melanoma cell lines with BRAF inhibitors promotes this complex, indicating that inhibition of the LATS1-SMAC might be necessary for BRAFV600E-driven melanoma. Finally, we show that LATS1-SMAC interaction is regulated by the SMAC mimetic Birinapant which requires the inhibition of C-IAP1 and the degradation of XIAP, indicating that the MST2/Hippo pathway is part of the mechanism of action of Birinapant. Overall, the current work shows SMAC-dependent apoptosis is regulated by the LATS1 tumour suppressor and supports the idea that LATS1 is a signalling hub that regulates the crosstalk between the MST2 pathway, the apoptotic network and the RAF/ERK pathway.
2022-08-18 | PXD032781 | Pride
Project description:Several groups reported the correlation between hypermethylation of RASSF1A and aggressiveness or a poor outcome in various pediatric tumors, including Wilms tumor. In addition, it is known that the overexpression of RASSF1A promotes apoptotic cell cycle arrest and reduces the tumorigenicity. In an attempt to identify epigenetic targets related to the biological features of rhabdoid tumor of the kidney (RTK), we analyzed the methylation level of the RASSF1A gene in RTK. RASSF1A promoter region in RTK is hypermethylated and the gene and protein expression levels were low. To examine the effect of re-expression of RASSF1A in RTK cells from the viewpoint of gene expression, we performed micro array analysis. We observed neither clear apoptosis induction nor cell-cycle arrest in RASSF1A-expressed RTK cell lines. Furthermore, the geneexpression profiling induced by RASSF1A expression in RTK cell line is curious, and CDK6 expression was significantly increased while CDKN2A expression was significantly decreased after RASSF1A expression. The changes in the gene expression profile that we observed in RTK cells after RASSF1A expression may not be causative events involving the suppression of cell proliferation, but rather antagonizingevents reflecting cellular responses against RASSF1A expression in RTK cells that are deficient in SMARCB1.
2024-04-05 | GSE171508 | GEO
Project description:The tumor suppressor gene RASSF1A (Ras association domain family protein 1A) coding for a microtubule stabilizing protein is epigenetically silenced in most human cancers. As a binding partner of the kinases MST1 and MST2, the mammalian orthologues of the Drosophila Hippo kinase, RASSF1A is a potential regulator of the Hippo tumor suppressor pathway. RASSF1A shares these properties with the scaffold protein SAV1. The role of this pathway in human cancer has remained enigmatic because Hippo pathway components are rarely mutated. Rassf1a homozygous knockout mice developed liver tumors. However, heterozygous deletion of Sav1 or co-deletion of Rassf1a and Sav1 produced liver tumors with much higher efficiency than single deletion of Rassf1a. Analysis of RASSF1A binding partners by mass spectrometry identified the Hippo kinases MST1, MST2 and the oncogenic IkB kinase TBK1 as the most significantly enriched RASSF1A-interacting proteins. The transcriptome of Rassf1a-/- livers was more deregulated than that of Sav1+/- livers and the transcriptome of Rassf1a-/-, Sav1+/- livers was similar to that of Rassf1a-/- mice. We found that the levels of Tbk1 protein were substantially upregulated in livers lacking Rassf1a, and at the transcript level, factors regulating Tbk1 stability, including Usp2 and Dtx4, were also dysregulated. Furthermore, transcripts of several beta tubulin isoforms were increased in the Rassf1a-deficient liver genotypes presumably reflecting a role of Rassf1a as a tubulin-binding and microtubule-stabilizing protein. Our data suggest a multifactorial role of Rassf1a in suppression of liver carcinogenesis. Analysis of gene expression in liver of wildtype 129 mice, Rassf1a-/- mice (RA), Sav1+/- mice (SA) and Rassf1a-/- Sav1+/- mice (RA_SA)
2016-05-31 | E-GEOD-73911 | biostudies-arrayexpress
Project description:Exposure to genotoxic stress promotes cell-cycle arrest and DNA repair or apoptosis. These “life” or “death” cell fate decisions often rely on the activity of the tumor suppressor gene p53. Therefore, how p53 activity is precisely regulated is essential to maintain tissue homeostasis and to prevent cancer development. Here we demonstrate that Drosophila p53 pro-apoptotic activity is regulated by the G2/M kinase Cdk1. We find that cell cycle arrested or endocycle-induced cells are refractory to ionizing radiation induced apoptosis. We show that the p53 protein is not able to bind to the p53 responding elements of the pro-apoptotic genes and to activate their expression in experimentally arrested cells. Our results indicate that p53 genetically and physically interacts with Cdk1 and that p53 pro-apoptotic role is regulated by the cell cycle status of the cell. We propose a model in which cell cycle progression and p53 pro-apoptotic activity are molecularly connected to coordinate the appropriate response after DNA damage.
2021-11-26 | GSE169668 | GEO
Project description:The decision of metazoan cells to live or undergo programmed cell death hinges on the balance between the levels of pro- versus anti-apoptotic gene products. The general RNA polymerase II (Pol II) transcription factor, TFIID, plays a central role in the regulation of gene expression through its core promoter recognition and co-activator functions. The core TFIID subunit TAF6 is a co-activator for the pro-apoptotic p53 tumour suppressor protein. Our previous studies identified a specialized isoform of TAF6, termed TAF6 that can specifically be induced in apoptosis. To elucidate the impact of TAF6 on gene expression and cell death, we employed modified antisense oligonucleotides to enforce expression of endogenous TAF6. The induction of endogenous TAF6 triggered apoptosis in several cancer cell lines. Importantly, TAF6 also induces apoptosis in tumor cell lines devoid of p53, placing TAF6 function downstream of p53. Microarray experiments uncovered a TAF6-induced transcriptome landscape displaying enhanced expression of genes of the Notch, oxidative stress, integrin, p53 and apoptosis pathways. Our data show that the TAF6 pathway is a pivotal signalling nexus that controls pro-apoptotic gene expression programs. Keywords: Treatment with splice site switching antisense oligonucleotides, induction of apoptosis
2010-11-27 | GSE8752 | GEO
Project description:The tumor suppressor gene RASSF1A (Ras association domain family protein 1A) coding for a microtubule stabilizing protein is epigenetically silenced in most human cancers. As a binding partner of the kinases MST1 and MST2, the mammalian orthologues of the Drosophila Hippo kinase, RASSF1A is a potential regulator of the Hippo tumor suppressor pathway. RASSF1A shares these properties with the scaffold protein SAV1. The role of this pathway in human cancer has remained enigmatic because Hippo pathway components are rarely mutated. Rassf1a homozygous knockout mice developed liver tumors. However, heterozygous deletion of Sav1 or co-deletion of Rassf1a and Sav1 produced liver tumors with much higher efficiency than single deletion of Rassf1a. Analysis of RASSF1A binding partners by mass spectrometry identified the Hippo kinases MST1, MST2 and the oncogenic IkB kinase TBK1 as the most significantly enriched RASSF1A-interacting proteins. The transcriptome of Rassf1a-/- livers was more deregulated than that of Sav1+/- livers and the transcriptome of Rassf1a-/-, Sav1+/- livers was similar to that of Rassf1a-/- mice. We found that the levels of Tbk1 protein were substantially upregulated in livers lacking Rassf1a, and at the transcript level, factors regulating Tbk1 stability, including Usp2 and Dtx4, were also dysregulated. Furthermore, transcripts of several beta tubulin isoforms were increased in the Rassf1a-deficient liver genotypes presumably reflecting a role of Rassf1a as a tubulin-binding and microtubule-stabilizing protein. Our data suggest a multifactorial role of Rassf1a in suppression of liver carcinogenesis.
2016-05-31 | GSE73911 | GEO
Project description:Mitochondria drive apoptosis by releasing pro-apoptotic proteins that promote caspase activation in the cytosol. The rhomboid-like protease PARL, an intramembrane cleaving peptidase in the inner membrane, regulates mitophagy and cell death pathways, but its role in apoptosis remained enigmatic. Here, we employed PARL-based proteomics to define its substrate spectrum. Our data identified the mitochondrial pro-apoptotic protein Smac/DIABLO as a PARL substrate. In apoptotic cells, Smac/DIABLO is released into the cytosol and promotes caspase activity by inhibiting IAPs. Intramembrane cleavage of Smac/DIABLO by PARL generates an amino terminal IAP-binding motif, which is required for its apoptotic activity. Loss of PARL impairs proteolytic maturation of Smac/DIABLO, which fails to bind XIAP. Smac/DIABLO peptidomimetics, downregulation of XIAP or cytosolic expression of cleaved Smac/DIABLO restores apoptosis in PARL-deficient cells. Our results discover a pro-apoptotic function of PARL and identify PARL-mediated Smac/DIABLO processing and cytochrome c release facilitated by OPA1 dependent cristae remodeling as two independent pro-apoptotic pathways in mitochondria. Please note that these data are overlapping with data uploaded under: PXD004914. Exclusively in this upload, you will find the S277A mutant immunoprecipitations.
2017-03-01 | PXD005712 | Pride
Project description:Malignancies arising from mutation of tumor suppressor genes display an unexplained tissue proclivity. For example, tumor suppressor BAP1 encodes a ubiquitously expressed deubiquitinase for histone H2A but germline mutations predominantly cause uveal melanomas and mesotheliomas. We show that BAP1 inactivation causes apoptosis in mouse embryonic stem cells, fibroblasts, liver and pancreas, whereas melanocytes and mesothelial cells remain viable. E3 ligase RNF2, which silences genes by monoubiquitinating H2A, promoted apoptosis in BAP1-deficient cells by suppressing the pro-survival genes Bcl-2 and Mcl-1. Our data argue that BAP1 modulates gene expression by countering H2A ubiquitination, but its loss only promotes tumorigenesis in cells that do not engage an RNF2-dependent apoptotic program. We propose that intolerance of BAP1 loss, and perhaps the loss of other tumor suppressors, restricts the mutant tumor spectrum.
2019-03-26 | GSE120414 | GEO