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1.
Cancer Cell ; 42(6): 943-945, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38861932

ABSTRACT

The development of mutant-selective KRAS inhibitors represents a major therapeutic advance; however, patients can develop resistance through feedback mechanisms and genetic alterations in the RAS pathway. Three publications in Nature and Cancer Discovery describe a promising RAS(ON) multi-selective inhibitor that simultaneously targets oncogenic RAS and multiple potential resistance mechanisms while sparing normal tissue.


Subject(s)
Neoplasms , Humans , Neoplasms/drug therapy , Neoplasms/genetics , Neoplasms/metabolism , Neoplasms/pathology , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/antagonists & inhibitors , Proto-Oncogene Proteins p21(ras)/metabolism , Animals , ras Proteins/metabolism , ras Proteins/genetics , Mutation , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Drug Resistance, Neoplasm/genetics , Signal Transduction/drug effects , Molecular Targeted Therapy/methods
2.
Science ; 384(6700): eadk0850, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38843329

ABSTRACT

To delineate the mechanisms by which the ERK1 and ERK2 mitogen-activated protein kinases support mutant KRAS-driven cancer growth, we determined the ERK-dependent phosphoproteome in KRAS-mutant pancreatic cancer. We determined that ERK1 and ERK2 share near-identical signaling and transforming outputs and that the KRAS-regulated phosphoproteome is driven nearly completely by ERK. We identified 4666 ERK-dependent phosphosites on 2123 proteins, of which 79 and 66%, respectively, were not previously associated with ERK, substantially expanding the depth and breadth of ERK-dependent phosphorylation events and revealing a considerably more complex function for ERK in cancer. We established that ERK controls a highly dynamic and complex phosphoproteome that converges on cyclin-dependent kinase regulation and RAS homolog guanosine triphosphatase function (RHO GTPase). Our findings establish the most comprehensive molecular portrait and mechanisms by which ERK drives KRAS-dependent pancreatic cancer growth.


Subject(s)
Mitogen-Activated Protein Kinase 1 , Mitogen-Activated Protein Kinase 3 , Pancreatic Neoplasms , Phosphoproteins , Proteome , Proto-Oncogene Proteins p21(ras) , Animals , Humans , Mice , Cell Line, Tumor , Cyclin-Dependent Kinases/metabolism , Cyclin-Dependent Kinases/genetics , MAP Kinase Signaling System , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Mutation , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/metabolism , Phosphoproteins/metabolism , Phosphoproteins/genetics , Phosphorylation , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , HEK293 Cells
3.
Nat Commun ; 15(1): 4773, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38862494

ABSTRACT

Spaceflight can change metabolic, immunological, and biological homeostasis and cause skin rashes and irritation, yet the molecular basis remains unclear. To investigate the impact of short-duration spaceflight on the skin, we conducted skin biopsies on the Inspiration4 crew members before (L-44) and after (R + 1) flight. Leveraging multi-omics assays including GeoMx™ Digital Spatial Profiler, single-cell RNA/ATAC-seq, and metagenomics/metatranscriptomics, we assessed spatial gene expressions and associated microbial and immune changes across 95 skin regions in four compartments: outer epidermis, inner epidermis, outer dermis, and vasculature. Post-flight samples showed significant up-regulation of genes related to inflammation and KRAS signaling across all skin regions. These spaceflight-associated changes mapped to specific cellular responses, including altered interferon responses, DNA damage, epithelial barrier disruptions, T-cell migration, and hindered regeneration were located primarily in outer tissue compartments. We also linked epithelial disruption to microbial shifts in skin swab and immune cell activity to PBMC single-cell data from the same crew and timepoints. Our findings present the inaugural collection and examination of astronaut skin, offering insights for future space missions and response countermeasures.


Subject(s)
Inflammation , Proto-Oncogene Proteins p21(ras) , Skin , Space Flight , Humans , Skin/immunology , Skin/metabolism , Skin/pathology , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Inflammation/immunology , Inflammation/genetics , Inflammation/metabolism , Male , Single-Cell Analysis , Adult , Middle Aged , Female , Metagenomics/methods , Gene Expression Profiling , Multiomics
4.
Science ; 384(6700): eadk0775, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38843331

ABSTRACT

How the KRAS oncogene drives cancer growth remains poorly understood. Therefore, we established a systemwide portrait of KRAS- and extracellular signal-regulated kinase (ERK)-dependent gene transcription in KRAS-mutant cancer to delineate the molecular mechanisms of growth and of inhibitor resistance. Unexpectedly, our KRAS-dependent gene signature diverges substantially from the frequently cited Hallmark KRAS signaling gene signature, is driven predominantly through the ERK mitogen-activated protein kinase (MAPK) cascade, and accurately reflects KRAS- and ERK-regulated gene transcription in KRAS-mutant cancer patients. Integration with our ERK-regulated phospho- and total proteome highlights ERK deregulation of the anaphase promoting complex/cyclosome (APC/C) and other components of the cell cycle machinery as key processes that drive pancreatic ductal adenocarcinoma (PDAC) growth. Our findings elucidate mechanistically the critical role of ERK in driving KRAS-mutant tumor growth and in resistance to KRAS-ERK MAPK targeted therapies.


Subject(s)
Carcinoma, Pancreatic Ductal , Extracellular Signal-Regulated MAP Kinases , Gene Expression Regulation, Neoplastic , MAP Kinase Signaling System , Mutation , Pancreatic Neoplasms , Proto-Oncogene Proteins p21(ras) , Transcriptome , Animals , Humans , Mice , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/pathology , Carcinoma, Pancreatic Ductal/metabolism , Cell Line, Tumor , Drug Resistance, Neoplasm/genetics , Extracellular Signal-Regulated MAP Kinases/metabolism , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , HEK293 Cells
5.
Nat Commun ; 15(1): 4969, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38862489

ABSTRACT

Metabolic remodeling is a strategy for tumor survival under stress. However, the molecular mechanisms during the metabolic remodeling of colorectal cancer (CRC) remain unclear. Melanocyte proliferating gene 1 (MYG1) is a 3'-5' RNA exonuclease and plays a key role in mitochondrial functions. Here, we uncover that MYG1 expression is upregulated in CRC progression and highly expressed MYG1 promotes glycolysis and CRC progression independent of its exonuclease activity. Mechanistically, nuclear MYG1 recruits HSP90/GSK3ß complex to promote PKM2 phosphorylation, increasing its stability. PKM2 transcriptionally activates MYC and promotes MYC-medicated glycolysis. Conversely, c-Myc also transcriptionally upregulates MYG1, driving the progression of CRC. Meanwhile, mitochondrial MYG1 on the one hand inhibits oxidative phosphorylation (OXPHOS), and on the other hand blocks the release of Cyt c from mitochondria and inhibits cell apoptosis. Clinically, patients with KRAS mutation show high expression of MYG1, indicating a high level of glycolysis and a poor prognosis. Targeting MYG1 may disturb metabolic balance of CRC and serve as a potential target for the diagnosis and treatment of CRC.


Subject(s)
Colorectal Neoplasms , Glycolysis , Mitochondria , Oxidative Phosphorylation , Humans , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Mitochondria/metabolism , Animals , Cell Line, Tumor , Mice , Carrier Proteins/metabolism , Carrier Proteins/genetics , Membrane Proteins/metabolism , Membrane Proteins/genetics , Thyroid Hormones/metabolism , Thyroid Hormones/genetics , Thyroid Hormone-Binding Proteins , Cell Nucleus/metabolism , Gene Expression Regulation, Neoplastic , Glycogen Synthase Kinase 3 beta/metabolism , Glycogen Synthase Kinase 3 beta/genetics , HSP90 Heat-Shock Proteins/metabolism , HSP90 Heat-Shock Proteins/genetics , Mice, Nude , Apoptosis/genetics , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Proto-Oncogene Proteins p21(ras)/genetics , Male , Female
6.
Nat Commun ; 15(1): 3741, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38702301

ABSTRACT

Targeted therapy is effective in many tumor types including lung cancer, the leading cause of cancer mortality. Paradigm defining examples are targeted therapies directed against non-small cell lung cancer (NSCLC) subtypes with oncogenic alterations in EGFR, ALK and KRAS. The success of targeted therapy is limited by drug-tolerant persister cells (DTPs) which withstand and adapt to treatment and comprise the residual disease state that is typical during treatment with clinical targeted therapies. Here, we integrate studies in patient-derived and immunocompetent lung cancer models and clinical specimens obtained from patients on targeted therapy to uncover a focal adhesion kinase (FAK)-YAP signaling axis that promotes residual disease during oncogenic EGFR-, ALK-, and KRAS-targeted therapies. FAK-YAP signaling inhibition combined with the primary targeted therapy suppressed residual drug-tolerant cells and enhanced tumor responses. This study unveils a FAK-YAP signaling module that promotes residual disease in lung cancer and mechanism-based therapeutic strategies to improve tumor response.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Drug Resistance, Neoplasm , Lung Neoplasms , Signal Transduction , Transcription Factors , YAP-Signaling Proteins , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Signal Transduction/drug effects , Transcription Factors/metabolism , Transcription Factors/genetics , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , YAP-Signaling Proteins/metabolism , Cell Line, Tumor , Animals , Drug Resistance, Neoplasm/genetics , Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/genetics , Neoplasm, Residual , Mice , Focal Adhesion Kinase 1/metabolism , Focal Adhesion Kinase 1/genetics , ErbB Receptors/metabolism , ErbB Receptors/genetics , Anaplastic Lymphoma Kinase/metabolism , Anaplastic Lymphoma Kinase/genetics , Anaplastic Lymphoma Kinase/antagonists & inhibitors , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Focal Adhesion Protein-Tyrosine Kinases/metabolism , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/pharmacology , Xenograft Model Antitumor Assays
7.
Nat Commun ; 15(1): 4642, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38821916

ABSTRACT

Post-translational modifications of proteins in malignant transformation and tumor maintenance of pancreatic ductal adenocarcinoma (PDAC) in the context of KRAS signaling remain poorly understood. Here, we use the KPC mouse model to examine the effect of palmitoylation on pancreatic cancer progression. ZDHHC20, upregulated by KRAS, is abnormally overexpressed and associated with poor prognosis in patients with pancreatic cancer. Dysregulation of ZDHHC20 promotes pancreatic cancer progression in a palmitoylation-dependent manner. ZDHHC20 inhibits the chaperone-mediated autophagic degradation of YTHDF3 through S-palmitoylation of Cys474, which can result in abnormal accumulation of the oncogenic product MYC and thereby promote the malignant phenotypes of cancer cells. Further, we design a biologically active YTHDF3-derived peptide to competitively inhibit YTHDF3 palmitoylation mediated by ZDHHC20, which in turn downregulates MYC expression and inhibits the progression of KRAS mutant pancreatic cancer. Thus, these findings highlight the therapeutic potential of targeting the ZDHHC20-YTHDF3-MYC signaling axis in pancreatic cancer.


Subject(s)
Acyltransferases , Carcinoma, Pancreatic Ductal , Disease Progression , Gene Expression Regulation, Neoplastic , Lipoylation , Pancreatic Neoplasms , Proto-Oncogene Proteins c-myc , Proto-Oncogene Proteins p21(ras) , Animals , Humans , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Acyltransferases/metabolism , Acyltransferases/genetics , Mice , Cell Line, Tumor , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/metabolism , Carcinoma, Pancreatic Ductal/pathology , RNA, Messenger/metabolism , RNA, Messenger/genetics , RNA-Binding Proteins/metabolism , RNA-Binding Proteins/genetics , Male , Signal Transduction , RNA Stability , Female
8.
Gen Physiol Biophys ; 43(3): 243-253, 2024 May.
Article in English | MEDLINE | ID: mdl-38774924

ABSTRACT

Cataract, a painless and progressive disorder is manifested as the opacification of the lens that represents the most significant cause of blindness worldwide. The objective of this study is to unveil the function of Kirsten rat sarcoma (KRAS) and potential action mechanisms against cataract. The ferroptosis-associated differentially expressed genes (DEGs) and pivot genes were extracted through the comprehensive bioinformatics methods. Erastin was applied for inducing ferroptosis in hydrogen peroxide (H2O2)-treated SRA01/04 cells, and validated by detecting content of intracellular iron, glutathione (GSH), malondialdehyde (MDA). Additionally, the effects of KRAS deficiency on ferroptosis were determined by functional assays. The proteins expression related to ferroptosis and Hippo pathway were determined by Western blotting. A total of 73 ferroptosis-related DEGs were discovered, and 6 critical core genes were confirmed upregulation in cataract cell model. The H2O2-treated SRA01/04 cells exhibited decrease of cell viability and proliferation, iron accumulation, MDA increase, GSH consumption, rise of COX2 and decline of GPX4, with further aggravated under erastin treatment, while the phenomena were improved by KRAS knockdown. Additionally, KRAS deficiency was involved in the Hippo signalling pathway activation. Downregulation of KRAS might restrain ferroptosis and affect Hippo pathway in cataract.


Subject(s)
Cataract , Ferroptosis , Hippo Signaling Pathway , Proto-Oncogene Proteins p21(ras) , Signal Transduction , Ferroptosis/drug effects , Cataract/metabolism , Cataract/genetics , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Humans , Signal Transduction/drug effects , Protein Serine-Threonine Kinases/metabolism , Protein Serine-Threonine Kinases/genetics , Cell Line
9.
Molecules ; 29(10)2024 May 15.
Article in English | MEDLINE | ID: mdl-38792177

ABSTRACT

The phosphorylation of different sites produces a significant effect on the conformational dynamics of KRAS. Gaussian accelerated molecular dynamics (GaMD) simulations were combined with deep learning (DL) to explore the molecular mechanism of the phosphorylation-mediated effect on conformational dynamics of the GTP-bound KRAS. The DL finds that the switch domains are involved in obvious differences in conformation contacts and suggests that the switch domains play a key role in the function of KRAS. The analyses of free energy landscapes (FELs) reveal that the phosphorylation of pY32, pY64, and pY137 leads to more disordered states of the switch domains than the wild-type (WT) KRAS and induces conformational transformations between the closed and open states. The results from principal component analysis (PCA) indicate that principal motions PC1 and PC2 are responsible for the closed and open states of the phosphorylated KRAS. Interaction networks were analyzed and the results verify that the phosphorylation alters interactions of GTP and magnesium ion Mg2+ with the switch domains. It is concluded that the phosphorylation pY32, pY64, and pY137 tune the activity of KRAS through changing conformational dynamics and interactions of the switch domains. We anticipated that this work could provide theoretical aids for deeply understanding the function of KRAS.


Subject(s)
Deep Learning , Guanosine Triphosphate , Molecular Dynamics Simulation , Protein Conformation , Proto-Oncogene Proteins p21(ras) , Proto-Oncogene Proteins p21(ras)/chemistry , Proto-Oncogene Proteins p21(ras)/metabolism , Proto-Oncogene Proteins p21(ras)/genetics , Phosphorylation , Guanosine Triphosphate/metabolism , Guanosine Triphosphate/chemistry , Humans , Protein Binding , Principal Component Analysis
10.
Int Rev Cell Mol Biol ; 386: 167-222, 2024.
Article in English | MEDLINE | ID: mdl-38782499

ABSTRACT

Historically, KRAS has been considered 'undruggable' inspite of being one of the most frequently altered oncogenic proteins in solid tumors, primarily due to the paucity of pharmacologically 'druggable' pockets within the mutant isoforms. However, pioneering developments in drug design capable of targeting the mutant KRAS isoforms especially KRASG12C-mutant cancers, have opened the doors for emergence of combination therapies comprising of a plethora of inhibitors targeting different signaling pathways. SHP2 signaling pathway, primarily known for activation of intracellular signaling pathways such as KRAS has come up as a potential target for such combination therapies as it emerged to be the signaling protein connecting KRAS and the immune signaling pathways and providing the link for understanding the overlapping regions of RAS/ERK/MAPK signaling cascade. Thus, SHP2 inhibitors having potent tumoricidal activity as well as role in immunomodulation have generated keen interest in researchers to explore its potential as combination therapy in KRAS mutant solid tumors. However, the excitement with these combination therapies need to overcome challenges thrown up by drug resistance and enhanced toxicity. In this review, we will discuss KRAS and SHP2 signaling pathways and their roles in immunomodulation and regulation of tumor microenvironment and also analyze the positive effects and drawbacks of the different combination therapies targeted at these signaling pathways along with their present and future potential to treat solid tumors.


Subject(s)
Immunomodulation , Neoplasms , Protein Tyrosine Phosphatase, Non-Receptor Type 11 , Proto-Oncogene Proteins p21(ras) , Signal Transduction , Humans , Protein Tyrosine Phosphatase, Non-Receptor Type 11/metabolism , Protein Tyrosine Phosphatase, Non-Receptor Type 11/antagonists & inhibitors , Neoplasms/drug therapy , Neoplasms/immunology , Neoplasms/metabolism , Neoplasms/therapy , Signal Transduction/drug effects , Proto-Oncogene Proteins p21(ras)/metabolism , Proto-Oncogene Proteins p21(ras)/genetics , Immunomodulation/drug effects , Animals , Treatment Outcome , Molecular Targeted Therapy
11.
J Am Chem Soc ; 146(23): 16173-16183, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38819260

ABSTRACT

Genetically encoding a proximal reactive warhead into the protein binder/drug has emerged as an efficient strategy for covalently binding to protein targets, enabling broad applications. To expand the reactivity scope for targeting the diverse natural residues under physiological conditions, the development of a genetically encoded reactive warhead with excellent stability and broad reactivity is highly desired. Herein, we reported the genetic encoding of epoxide-containing tyrosine (EPOY) for developing covalent protein drugs. Our study demonstrates that EPOY, when incorporated into a nanobody (KN035), can cross-link with different side chains (mutations) at the same position of PD-L1 protein. Significantly, a single genetically encoded reactive warhead that is capable of covalent and site-specific targeting to 10 different nucleophilic residues was achieved for the first time. This would largely expand the scope of covalent warhead and inspire the development of covalent warheads for both small-molecule drugs and protein drugs. Furthermore, we incorporate the EPOY into a designed ankyrin repeat protein (DarpinK13) to create the covalent binders of KRAS. This covalent KRAS binder holds the potential to achieve pan-covalent targeting of KRAS based on the structural similarity among all oncogenic KRAS mutants while avoiding off-target binding to NRAS/HRAS through a covalent interaction with KRAS-specific residues (H95 and E107). We envision that covalently targeting to H95 will be a promising strategy for the development of covalent pan-KRAS inhibitors in the future.


Subject(s)
Epoxy Compounds , Humans , Epoxy Compounds/chemistry , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/chemistry , Proto-Oncogene Proteins p21(ras)/antagonists & inhibitors , Proto-Oncogene Proteins p21(ras)/metabolism , Tyrosine/chemistry , B7-H1 Antigen/chemistry , B7-H1 Antigen/metabolism , B7-H1 Antigen/antagonists & inhibitors , Single-Domain Antibodies/chemistry , Single-Domain Antibodies/metabolism
12.
J Control Release ; 370: 614-625, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38729436

ABSTRACT

Mutations in RAS, a family of proteins found in all human cells, drive a third of cancers, including many pancreatic, colorectal, and lung cancers. However, there is a lack of clinical therapies that can effectively prevent RAS from causing tumor growth. Recently, a protease was engineered that specifically degrades active RAS, offering a promising new tool for treating these cancers. However, like many other intracellularly acting protein-based therapies, this protease requires a delivery vector to reach its site of action within the cell. In this study, we explored the incorporation of cationic lipids into ionizable lipid nanoparticles (LNPs) to develop a RAS protease delivery platform capable of inhibiting cancer cell proliferation in vitro and in vivo. A library of 13 LNPs encapsulating RAS protease was designed, and each formulation was evaluated for in vitro delivery efficiency and toxicity. A subset of four top-performing LNP formulations was identified and further evaluated for their impact on cancer cell proliferation in human colorectal cancer cells with mutated KRAS in vitro and in vivo, as well as their in vivo biodistribution and toxicity. In vivo, both the concentration of cationic lipid and type of cargo influenced LNP and cargo distribution. All lead candidate LNPs showed RAS protease functionality in vitro, and the top-performing formulation achieved effective intracellular RAS protease delivery in vivo, decreasing cancer cell proliferation in an in vivo xenograft model and significantly reducing tumor growth and size. Overall, this work demonstrates the use of LNPs as an effective delivery platform for RAS proteases, which could potentially be utilized for cancer therapies.


Subject(s)
Cell Proliferation , Lipids , Nanoparticles , Humans , Animals , Cell Proliferation/drug effects , Nanoparticles/administration & dosage , Nanoparticles/chemistry , Lipids/chemistry , Cell Line, Tumor , Mice, Nude , Female , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , ras Proteins/metabolism , Tissue Distribution , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Neoplasms/drug therapy , Neoplasms/pathology , Mice , Drug Delivery Systems
13.
Protein Sci ; 33(6): e5016, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38747381

ABSTRACT

RAF kinases are key components of the RAS-MAPK signaling pathway, which drives cell growth and is frequently overactivated in cancer. Upstream signaling activates the small GTPase RAS, which recruits RAF to the cell membrane, driving a transition of the latter from an auto-inhibited monomeric conformation to an active dimer. Despite recent progress, mechanistic details underlying RAF activation remain unclear, particularly the role of RAS and the membrane in mediating this conformational rearrangement of RAF together with 14-3-3 to permit RAF kinase domain dimerization. Here, we reconstituted an active complex of dimeric BRAF, a 14-3-3 dimer and two KRAS4B on a nanodisc bilayer and verified that its assembly is GTP-dependent. Biolayer interferometry (BLI) was used to compare the binding affinities of monomeric versus dimeric full-length BRAF:14-3-3 complexes for KRAS4B-conjugated nanodiscs (RAS-ND) and to investigate the effects of membrane lipid composition and spatial density of KRAS4B on binding. 1,2-Dioleoyl-sn-glycero-3-phospho-L-serine (DOPS) and higher KRAS4B density enhanced the interaction of BRAF:14-3-3 with RAS-ND to different degrees depending on BRAF oligomeric state. We utilized our reconstituted system to dissect the effects of KRAS4B and the membrane on the kinase activity of monomeric and dimeric BRAF:14-3-3 complexes, finding that KRAS4B or nanodiscs alone were insufficient to stimulate activity, whereas RAS-ND increased activity of both states of BRAF. The reconstituted assembly of full-length BRAF with 14-3-3 and KRAS on a cell-free, defined lipid bilayer offers a more holistic biophysical perspective to probe regulation of this multimeric signaling complex at the membrane surface.


Subject(s)
14-3-3 Proteins , Cell-Free System , Nanostructures , Proto-Oncogene Proteins B-raf , Proto-Oncogene Proteins p21(ras) , Humans , 14-3-3 Proteins/metabolism , 14-3-3 Proteins/chemistry , 14-3-3 Proteins/genetics , Lipid Bilayers/chemistry , Lipid Bilayers/metabolism , Nanostructures/chemistry , Protein Binding , Protein Multimerization , Proto-Oncogene Proteins B-raf/chemistry , Proto-Oncogene Proteins B-raf/metabolism , Proto-Oncogene Proteins B-raf/genetics , Proto-Oncogene Proteins p21(ras)/chemistry , Proto-Oncogene Proteins p21(ras)/metabolism , Proto-Oncogene Proteins p21(ras)/genetics
14.
J Med Chem ; 67(11): 8569-8584, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38758695

ABSTRACT

The trafficking chaperone PDE6D (or PDEδ) was proposed as a surrogate target for K-Ras, leading to the development of a series of inhibitors that block its prenyl binding pocket. These inhibitors suffered from low solubility and suspected off-target effects, preventing their clinical development. Here, we developed a highly soluble, low nanomolar PDE6D inhibitor (PDE6Di), Deltaflexin3, which has the lowest off-target activity as compared to three prominent reference compounds. Deltaflexin3 reduces Ras signaling and selectively decreases the growth of KRAS mutant and PDE6D-dependent cancer cells. We further show that PKG2-mediated phosphorylation of Ser181 lowers K-Ras binding to PDE6D. Thus, Deltaflexin3 combines with the approved PKG2 activator Sildenafil to more potently inhibit PDE6D/K-Ras binding, cancer cell proliferation, and microtumor growth. As observed previously, inhibition of Ras trafficking, signaling, and cancer cell proliferation remained overall modest. Our results suggest reevaluating PDE6D as a K-Ras surrogate target in cancer.


Subject(s)
Cell Proliferation , Cyclic Nucleotide Phosphodiesterases, Type 6 , Proto-Oncogene Proteins p21(ras) , Sildenafil Citrate , Humans , Cyclic Nucleotide Phosphodiesterases, Type 6/antagonists & inhibitors , Cyclic Nucleotide Phosphodiesterases, Type 6/metabolism , Sildenafil Citrate/pharmacology , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/antagonists & inhibitors , Proto-Oncogene Proteins p21(ras)/metabolism , Cell Proliferation/drug effects , Cell Line, Tumor , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Mutation , Animals , Structure-Activity Relationship , Phosphodiesterase Inhibitors/pharmacology , Phosphodiesterase Inhibitors/chemistry , Phosphodiesterase Inhibitors/chemical synthesis
15.
J Proteome Res ; 23(6): 2160-2168, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38767394

ABSTRACT

Resistance is a major problem with effective cancer treatment and the stroma forms a significant portion of the tumor mass but traditional drug screens involve cancer cells alone. Cancer-associated fibroblasts (CAFs) are a major tumor stroma component and its secreted proteins may influence the function of cancer cells. The majority of secretome studies compare different cancer or CAF cell lines exclusively. Here, we present the direct characterization of the secreted protein profiles between CAFs and KRAS mutant-cancer cell lines from colorectal, lung, and pancreatic tissues using multiplexed mass spectrometry. 2573 secreted proteins were annotated, and differential analysis highlighted understudied CAF-enriched secreted proteins, including Wnt family member 5B (WNT5B), in addition to established CAF markers, such as collagens. The functional role of CAF secreted proteins was explored by assessing its effect on the response to 97 anticancer drugs since stromal cells may cause a differing cancer drug response, which may be missed on routine drug screening using cancer cells alone. CAF secreted proteins caused specific effects on each of the cancer cell lines, which highlights the complexity and challenges in cancer treatment and so the importance to consider stromal elements.


Subject(s)
Cancer-Associated Fibroblasts , Secretome , Humans , Cancer-Associated Fibroblasts/metabolism , Cancer-Associated Fibroblasts/drug effects , Cancer-Associated Fibroblasts/pathology , Cell Line, Tumor , Secretome/metabolism , Antineoplastic Agents/pharmacology , Drug Resistance, Neoplasm , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Neoplasms/drug therapy , Neoplasms/metabolism , Neoplasms/pathology , Mass Spectrometry , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/pathology , Proteomics/methods , Lung Neoplasms/metabolism , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Lung Neoplasms/genetics
16.
Int J Mol Sci ; 25(9)2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38731942

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) can originate from acinar-to-ductal metaplasia (ADM). Pancreatic acini harboring oncogenic Kras mutations are transdifferentiated to a duct-like phenotype that further progresses to become pancreatic intraepithelial neoplasia (PanIN) lesions, giving rise to PDAC. Although ADM formation is frequently observed in KrasG12D transgenic mouse models of PDAC, the exact mechanisms of how oncogenic KrasG12D regulates this process remain an enigma. Herein, we revealed a new downstream target of oncogenic Kras, cytokine CCL9, during ADM formation. Higher levels of CCL9 and its receptors, CCR1 and CCR3, were detected in ADM regions of the pancreas in p48cre:KrasG12D mice and human PDAC patients. Knockdown of CCL9 in KrasG12D-expressed pancreatic acini reduced KrasG12D-induced ADM in a 3D organoid culture system. Moreover, exogenously added recombinant CCL9 and overexpression of CCL9 in primary pancreatic acini induced pancreatic ADM. We also showed that, functioning as a downstream target of KrasG12D, CCL9 promoted pancreatic ADM through upregulation of the intracellular levels of reactive oxygen species (ROS) and metalloproteinases (MMPs), including MMP14, MMP3 and MMP2. Blockade of MMPs via its generic inhibitor GM6001 or knockdown of specific MMP such as MMP14 and MMP3 decreased CCL9-induced pancreatic ADM. In p48cre:KrasG12D transgenic mice, blockade of CCL9 through its specific neutralizing antibody attenuated pancreatic ADM structures and PanIN lesion formation. Furthermore, it also diminished infiltrating macrophages and expression of MMP14, MMP3 and MMP2 in the ADM areas. Altogether, our results provide novel mechanistic insight into how oncogenic Kras enhances pancreatic ADM through its new downstream target molecule, CCL9, to initiate PDAC.


Subject(s)
Acinar Cells , Carcinoma, Pancreatic Ductal , Metaplasia , Pancreatic Neoplasms , Proto-Oncogene Proteins p21(ras) , Reactive Oxygen Species , Animals , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Mice , Reactive Oxygen Species/metabolism , Humans , Carcinoma, Pancreatic Ductal/metabolism , Carcinoma, Pancreatic Ductal/pathology , Carcinoma, Pancreatic Ductal/genetics , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/genetics , Metaplasia/metabolism , Metaplasia/genetics , Acinar Cells/metabolism , Acinar Cells/pathology , Mice, Transgenic , Chemokines, CC/metabolism , Chemokines, CC/genetics , Macrophage Inflammatory Proteins/metabolism , Macrophage Inflammatory Proteins/genetics , Pancreas/metabolism , Pancreas/pathology
17.
Bioorg Chem ; 148: 107467, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38772290

ABSTRACT

KRAS-G12C inhibitors has been made significant progress in the treatment of KRAS-G12C mutant cancers, but their clinical application is limited due to the adaptive resistance, motivating development of novel structural inhibitors. Herein, series of coumarin derivatives as KRAS-G12C inhibitors were found through virtual screening and rational structural optimization. Especially, K45 exhibited strong antiproliferative potency on NCI-H23 and NCI-H358 cancer cells harboring KRAS-G12C with the IC50 values of 0.77 µM and 1.50 µM, which was 15 and 11 times as potent as positive drug ARS1620, respectively. Furthermore, K45 reduced the phosphorylation of KRAS downstream effectors ERK and AKT by reducing the active form of KRAS (KRAS GTP) in NCI-H23 cells. In addition, K45 induced cell apoptosis by increasing the expression of anti-apoptotic protein BAD and BAX in NCI-H23 cells. Docking studies displayed that the 3-naphthylmethoxy moiety of K45 extended into the cryptic pocket formed by the residues Gln99 and Val9, which enhanced the interaction with the KRAS-G12C protein. These results indicated that K45 was a potent KRAS-G12C inhibitor worthy of further study.


Subject(s)
Antineoplastic Agents , Cell Proliferation , Coumarins , Drug Screening Assays, Antitumor , Proto-Oncogene Proteins p21(ras) , Humans , Proto-Oncogene Proteins p21(ras)/antagonists & inhibitors , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Coumarins/chemistry , Coumarins/pharmacology , Coumarins/chemical synthesis , Structure-Activity Relationship , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Cell Proliferation/drug effects , Molecular Structure , Cell Line, Tumor , Dose-Response Relationship, Drug , Drug Discovery , Apoptosis/drug effects , Molecular Docking Simulation , Drug Evaluation, Preclinical
18.
Bioorg Chem ; 148: 107460, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38781668

ABSTRACT

A series of genipin derivatives were designed and synthesized as potential inhibitors targeted KRAS G12D mutation. The majority of these compounds demonstrated potential antiproliferative effects against KRAS G12D mutant tumor cells (CT26 and A427). Notably, seven compounds exhibited the anticancer effects with IC50 values ranging from 7.06 to 9.21 µM in CT26 (KRASG12D) and A427 (KRASG12D) cells and effectively suppressed the colony formation of CT26 cells. One representative compound SK12 was selected for further investigation into biological activity and action mechanisms. SK12 markedly induced apoptosis in CT26 cells in a concentration-dependent manner. Moreover, SK12 elevated the levels of reactive oxygen species (ROS) in tumor cells and exhibited a modulatory effect on the KRAS signaling pathway, thereby inhibiting the activation of downstream phosphorylated proteins. The binding affinity of SK12 to KRAS G12D protein was further confirmed by the surface plasmon resonance (SPR) assay with a binding KD of 157 µM. SK12 also exhibited notable anticancer efficacy in a nude mice tumor model. The relative tumor proliferation rate (T/C) of the experimental group (50 mg/kg) was 31.04 % (P < 0.05), while maintaining a commendable safety profile.


Subject(s)
Antineoplastic Agents , Cell Proliferation , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Iridoids , Mice, Nude , Proto-Oncogene Proteins p21(ras) , Humans , Iridoids/pharmacology , Iridoids/chemistry , Animals , Proto-Oncogene Proteins p21(ras)/antagonists & inhibitors , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Cell Proliferation/drug effects , Structure-Activity Relationship , Mice , Molecular Structure , Apoptosis/drug effects , Drug Discovery , Cell Line, Tumor , Mutation , Mice, Inbred BALB C , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/pathology , Neoplasms, Experimental/metabolism
19.
Sci Signal ; 17(836): eadd5073, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38743809

ABSTRACT

The Ras-mitogen-activated protein kinase (MAPK) pathway is a major target for cancer treatment. To better understand the genetic pathways that modulate cancer cell sensitivity to MAPK pathway inhibitors, we performed a CRISPR knockout screen with MAPK pathway inhibitors on a colorectal cancer (CRC) cell line carrying mutant KRAS. Genetic deletion of the catalytic subunit of protein phosphatase 6 (PP6), encoded by PPP6C, rendered KRAS- and BRAF-mutant CRC and BRAF-mutant melanoma cells more resistant to these inhibitors. In the absence of MAPK pathway inhibition, PPP6C deletion in CRC cells decreased cell proliferation in two-dimensional (2D) adherent cultures but accelerated the growth of tumor spheroids in 3D culture and tumor xenografts in vivo. PPP6C deletion enhanced the activation of nuclear factor κB (NF-κB) signaling in CRC and melanoma cells and circumvented the cell cycle arrest and decreased cyclin D1 abundance induced by MAPK pathway blockade in CRC cells. Inhibiting NF-κB activity by genetic and pharmacological means restored the sensitivity of PPP6C-deficient cells to MAPK pathway inhibition in CRC and melanoma cells in vitro and in CRC cells in vivo. Furthermore, a R264 point mutation in PPP6C conferred loss of function in CRC cells, phenocopying the enhanced NF-κB activation and resistance to MAPK pathway inhibition observed for PPP6C deletion. These findings demonstrate that PP6 constrains the growth of KRAS- and BRAF-mutant cancer cells, implicates the PP6-NF-κB axis as a modulator of MAPK pathway output, and presents a rationale for cotargeting the NF-κB pathway in PPP6C-mutant cancer cells.


Subject(s)
MAP Kinase Signaling System , NF-kappa B , Proto-Oncogene Proteins B-raf , Proto-Oncogene Proteins p21(ras) , Humans , Proto-Oncogene Proteins B-raf/genetics , Proto-Oncogene Proteins B-raf/metabolism , Proto-Oncogene Proteins B-raf/antagonists & inhibitors , NF-kappa B/metabolism , NF-kappa B/genetics , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , MAP Kinase Signaling System/drug effects , Animals , Cell Line, Tumor , Mutation , Mice , Protein Kinase Inhibitors/pharmacology , Cell Proliferation/drug effects , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Melanoma/genetics , Melanoma/metabolism , Melanoma/drug therapy , Melanoma/pathology , Xenograft Model Antitumor Assays , Drug Resistance, Neoplasm/genetics , Drug Resistance, Neoplasm/drug effects , Mice, Nude
20.
Int J Biol Macromol ; 270(Pt 2): 132477, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38772459

ABSTRACT

KRASG12D are the most prevalent oncogenic mutations and a promising target for solid tumor therapies. However, its inhibition exhibits tremendous challenge due to the necessity of high binding affinity to obviate the need for covalent binders. Here we report the evidence of a novel class of Imidazo[1,2-a]pyridine derivative as potentially significant novel inhibitors of KRASG12D, discovered through extensive ligand-based screening against 2-[(2R)-piperidin-2-yl]-1H-indole, an important scaffold for KRASG12D inhibition via switch-I/II (S-I/II) pocket. The proposed compounds exhibited similar binding affinities and overlapped pose configurations to 2-[(2R)-piperidin-2-yl]-1H-indole, serving as a reliable starting point for drug discovery. Comparative free energy profiles demonstrated that C4 [2-methyl-3-((5-phenyl-1H-1,2,4-triazol-3-yl)methyl)imidazo[1,2-a]pyridine] effectively shifted the protein to a stable low-energy conformation via a prominent transition state. The conformational changes across the transition revealed the conformational shift of switch-I and II to a previously known off-like conformation of inactive KRASG12D with rmsd of 0.91 Å. These conformations were even more prominent than the privileged scaffold 2-[(2R)-piperidin-2-yl]-1H-indole. The representative structure overlay of C4 and another X-ray crystallography solved BI-2852 bound inactive KRASG12D revealed that Switch-I and II exhibited off-like conformations. The cumulative variance across the first eigenvalue that accounted for 57 % of the collective variance validated this on-to-off transition. In addition, the relative interaction of C4 binding showed consistent patterns with BI-2852. Taken together, our results support the inhibitory activity of [2-methyl-3-((5-phenyl-1H-1,2,4-triazol-3-yl)methyl)imidazo[1,2-a]pyridine] by shifting active KRASG12D to an inactive conformation.


Subject(s)
Proto-Oncogene Proteins p21(ras) , Pyridines , Pyridines/chemistry , Pyridines/pharmacology , Proto-Oncogene Proteins p21(ras)/antagonists & inhibitors , Proto-Oncogene Proteins p21(ras)/chemistry , Proto-Oncogene Proteins p21(ras)/metabolism , Proto-Oncogene Proteins p21(ras)/genetics , Humans , Imidazoles/chemistry , Imidazoles/pharmacology , Protein Conformation , Molecular Docking Simulation , Protein Binding , Mutation
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