Similar Datasets
Project description:Although KRAS mutation is a hallmark of pancreatic ductal adenocarcinoma (PDA), mutated KRAS remains an intractable pharmacological target. Consequently, an understanding of the RAS effector pathway(s) required for PDA maintenance is critical for improved strategies to treat this disease. Here we demonstrate that expression of BRAFV600E, but not PIK3CAH1047R, in the mouse pancreas led to PanIn lesions. Moreover, concomitant expression of BRAFV600E and TP53R270H resulted in lethal PDA. A large panel of PDA cell line panel was deployed to derive genomic classifiers of MEK inhibitor sensitivity. This classifier correctly predicted survival benefit in two novel in vivo syngeneic, orthotopic models of PDA. Consequently, we conclude that RAF?MEK?ERK signaling is central to the initiation, progression and maintenance of PDA and propose predictive biomarkers of response to MEK inhibition. These data further emphasize the value of leveraging multiple experimental systems to prioritize pathways for intervention in human PDA. RNA was extracted from human PDA cell line samples and hybridized on Affymetrix U133 plus 2.0 microarrays. The CEL files were processed using R based Bioconductor and normalized values were obtained using RMA. RNA was extracted from mouse PDA cell lines and hybridized on Affymetrix Mouse 430a 2.0 microarrays. The CEL files were processed using R based Bioconductor and normalized values were obtained using RMA.
2012-07-09 | E-GEOD-30562 | biostudies-arrayexpress
Project description:Disruption of the MAPK pathway in cancer by kinase inhibition often fails due to pathway reactivation, causing clinical relapse. Among MAPK inhibitors, type I RAF inhibitors are only active against specific BRAF mutants; MEK inhibitor monotherapy is associated with limited clinical benefits but may serve as a foundation for combinatorial therapy. Here, we show that type II RAF plus allosteric MEK inhibitors durably blunt the development of acquired MEK inhibitor resistance among cancers with KRAS, NRAS, NF1, BRAFnon-V600 and BRAFV600 mutations, when compared to a combination of type II RAF plus ERK inhibitors. Type II RAF and MEK (versus ERK) inhibitors also display superior capacity to sequester MEK in RAF complexes and uncouple MEK and ERK interaction in acquired resistant tumor subpopulations. Systemically and intratumorally, type II RAF plus MEK inhibitors expand memory and activated/exhausted CD8+ T-cells. Whereas trametinib alone temporally reduces dominant intra-tumoral T-cell clones, type II RAF inhibitor co-treatment reverses this effect and promotes T-cell clonotypic expansion and convergence. Importantly, durably control of tumors by this combination requires CD8+ T-cells. Thus, the prolonged anti-tumor efficacy of type II RAF plus MEK inhibitors reveals exquisite MAPK addiction in common lethal cancer histologies, and the mechanisms include unexpected allosteric perturbation of the MAPK pathway and engagement of anti-tumor CD8+ T-cell immunity.
2021-06-06 | GSE158608 | GEO
Project description:Disruption of the MAPK pathway in cancer by kinase inhibition often fails due to pathway reactivation, causing clinical relapse. Among MAPK inhibitors, type I RAF inhibitors are only active against specific BRAF mutants; MEK inhibitor monotherapy is associated with limited clinical benefits but may serve as a foundation for combinatorial therapy. Here, we show that type II RAF plus allosteric MEK inhibitors durably blunt the development of acquired MEK inhibitor resistance among cancers with KRAS, NRAS, NF1, BRAFnon-V600 and BRAFV600 mutations, when compared to a combination of type II RAF plus ERK inhibitors. Type II RAF and MEK (versus ERK) inhibitors also display superior capacity to sequester MEK in RAF complexes and uncouple MEK and ERK interaction in acquired resistant tumor subpopulations. Systemically and intratumorally, type II RAF plus MEK inhibitors expand memory and activated/exhausted CD8+ T-cells. Whereas trametinib alone temporally reduces dominant intra-tumoral T-cell clones, type II RAF inhibitor co-treatment reverses this effect and promotes T-cell clonotypic expansion and convergence. Importantly, durably control of tumors by this combination requires CD8+ T-cells. Thus, the prolonged anti-tumor efficacy of type II RAF plus MEK inhibitors reveals exquisite MAPK addiction in common lethal cancer histologies, and the mechanisms include unexpected allosteric perturbation of the MAPK pathway and engagement of anti-tumor CD8+ T-cell immunity.
2021-06-06 | GSE158607 | GEO
Project description:Disruption of the MAPK pathway in cancer by kinase inhibition often fails due to pathway reactivation, causing clinical relapse. Among MAPK inhibitors, type I RAF inhibitors are only active against specific BRAF mutants; MEK inhibitor monotherapy is associated with limited clinical benefits but may serve as a foundation for combinatorial therapy. Here, we show that type II RAF plus allosteric MEK inhibitors durably blunt the development of acquired MEK inhibitor resistance among cancers with KRAS, NRAS, NF1, BRAFnon-V600 and BRAFV600 mutations, when compared to a combination of type II RAF plus ERK inhibitors. Type II RAF and MEK (versus ERK) inhibitors also display superior capacity to sequester MEK in RAF complexes and uncouple MEK and ERK interaction in acquired resistant tumor subpopulations. Systemically and intratumorally, type II RAF plus MEK inhibitors expand memory and activated/exhausted CD8+ T-cells. Whereas trametinib alone temporally reduces dominant intra-tumoral T-cell clones, type II RAF inhibitor co-treatment reverses this effect and promotes T-cell clonotypic expansion and convergence. Importantly, durably control of tumors by this combination requires CD8+ T-cells. Thus, the prolonged anti-tumor efficacy of type II RAF plus MEK inhibitors reveals exquisite MAPK addiction in common lethal cancer histologies, and the mechanisms include unexpected allosteric perturbation of the MAPK pathway and engagement of anti-tumor CD8+ T-cell immunity.
2021-06-06 | GSE158609 | GEO
Project description:The signaling network of skeletal muscle cells is controlled by a variety of protein kinases. Although many kinases are known players, their downstream targets are still largely unexplored. To gain further knowledge about the PI3K-AKT-mTOR-S6K and the RAF-MEK-ERK-RSK signaling networks in myotubes, we analyzed changes in protein phosphorylation levels upon pathway activation and direct kinase inhibition on a global scale. Based on the phosphoproteomics data, we further examined target relationships of the basophilic kinases AKT, RSK and S6K, which share the substrate recognition motif RxRxxp[ST].
2023-02-22 | PXD029678 | Pride
Project description:An inducible oncogenic cell line ZFL-ΔRaf1-ER was established, in which oncogenic human Raf-1(ΔRaf1) can be activated in zebrafish liver cells by administration of 4-hydroxytamoxifen (4HT). Transcriptional profilling of the ZFL-ΔRaf1-ER cells with and without administration of 4HT and/or the MEK inhibitor U0126 defined the gene signatures transcriptionally regulated by hyperactive Raf/MEK/MAPK signaling in zebrafish liver cells.
2011-07-07 | GSE29308 | GEO
Project description:Various protein kinases are regulating the intracellular signaling network of skeletal muscle cells. Despite that many of the involved kinases are known, their downstream targets have remained largely unexplored. To deepen our understanding of the PI3K-AKT-mTOR-S6K and the RAF-MEK-ERK-RSK signaling network in myotubes, we globally analyzed changes in protein phosphorylation levels upon kinase inhibition within these pathways. The phosphoproteomics data were used to define potential targets of the kinases AKT, RSK and S6K, which share the substrate recognition motif RxRxxp[ST].
2023-02-22 | PXD018667 | Pride
Project description:Small molecule inhibitors of BRAF and MEK have proven effective at inhibiting tumor growth in melanoma patients, however this efficacy is limited due to the almost universal development of drug resistance. To provide advanced insight into the signaling responses that occur following kinase inhibition we have performed quantitative (phospho)-proteomics of human melanoma cells treated with either Dabrafenib, a BRAF inhibitor; Trametinib, a MEK inhibitor or SCH772984, an ERK inhibitor. Over nine experiments we identified 7827 class I phosphosites on 4960 proteins. This included 54 phosphorylation sites that were significantly down-modulated after exposure to all three inhibitors, 34 of which have not been previously reported. Functional analysis of these novel ERK targets identified roles for them in GTPase activity and regulation, apoptosis and cell-cell adhesion. Comparison of the results presented here with previously reported phosphorylation sites downstream of ERK showed a limited degree of overlap suggesting that ERK signaling responses may be highly cell line and cue specific. In addition we identified 26 phosphorylation sites that were only responsive to Dabrafenib. We provide further orthogonal experimental evidence for 3 of these sites in human embryonic kidney cells over-expressing BRAF as well as further computational insights using KinomeXplorer. The validated phosphorylation sites were found to be involved in actin regulation, which has been proposed as a novel mechanism for inhibiting resistance development. These results would suggest that the linearity of the BRAF-MEK-ERK pathway is at least context dependent.
2019-11-11 | PXD013923 | Pride
Project description:Neurofibromatosis Type 1 (NF1) patients develop benign neurofibromas and malignant peripheral nerve sheath tumors (MPNST). These incurable peripheral nerve tumors result from loss of NF1 tumor suppressor gene function, causing hyperactive Ras signaling. Activated Ras controls numerous downstream effectors, but specific pathways mediating effects of hyperactive Ras in NF1 tumors are unknown. Cross-species transcriptome analyses of mouse and human neurofibromas and MPNSTs identified global negative feedback of genes that regulate Ras-Raf- MEK- extracellular signal-regulated protein kinase (ERK) signaling in both species. Nonetheless, activation of ERK was sustained in mouse and human neurofibromas and MPNST. PD0325901, a highly selective pharmacological inhibitor of MEK, was used to test whether sustained Ras-Raf-MEK-ERK signaling contributes to neurofibroma growth in the Nf1fl/fl;Dhh-cre mouse model or in NF1 patient MPNST cell xenografts. PD0325901 treatment reduced aberrantly proliferating cells in neurofibroma and MPNST, prolonged survival of mice implanted with human MPNST cells, and shrank neurofibromas in >80% of mice tested. PD0325901 also caused effects on tumor vasculature. Our data demonstrate that deregulated Ras/ERK signaling is critical for the growth of NF1 peripheral nerve tumors and provide strong rationale for testing MEK inhibitors in NF1 clinical trials.
2012-12-28 | GSE41747 | GEO
Project description:An inducible oncogenic cell line ZFL-?Raf1-ER was established, in which oncogenic human Raf-1(?Raf1) can be activated in zebrafish liver cells by administration of 4-hydroxytamoxifen (4HT). Transcriptional profilling of the ZFL-?Raf1-ER cells with and without administration of 4HT and/or the MEK inhibitor U0126 defined the gene signatures transcriptionally regulated by hyperactive Raf/MEK/MAPK signaling in zebrafish liver cells. The ZFL-?Raf1-ER cells were cultured in 12-well plates till confluence. Cell were starved for 4h in plain medium and susequently treated with or without 1µM 4HT and/or 30µM U0126 for 12h. Biological triplications were taken for each condition.
2011-07-07 | E-GEOD-29308 | biostudies-arrayexpress