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Cell Research Apr 2020Adaptive immunity is essential for pathogen and tumor eradication, but may also trigger uncontrolled or pathological inflammation. T cell receptor, co-stimulatory and... (Review)
Review
Adaptive immunity is essential for pathogen and tumor eradication, but may also trigger uncontrolled or pathological inflammation. T cell receptor, co-stimulatory and cytokine signals coordinately dictate specific signaling networks that trigger the activation and functional programming of T cells. In addition, cellular metabolism promotes T cell responses and is dynamically regulated through the interplay of serine/threonine kinases, immunological cues and nutrient signaling networks. In this review, we summarize the upstream regulators and signaling effectors of key serine/threonine kinase-mediated signaling networks, including PI3K-AGC kinases, mTOR and LKB1-AMPK pathways that regulate metabolism, especially in T cells. We also provide our perspectives about the pending questions and clinical applicability of immunometabolic signaling. Understanding the regulators and effectors of immunometabolic signaling networks may uncover therapeutic targets to modulate metabolic programming and T cell responses in human disease.
Topics: AMP-Activated Protein Kinase Kinases; AMP-Activated Protein Kinases; Animals; Humans; Phosphatidylinositol 3-Kinases; Protein Serine-Threonine Kinases; Signal Transduction; T-Lymphocytes; TOR Serine-Threonine Kinases
PubMed: 32203134
DOI: 10.1038/s41422-020-0301-1 -
Pharmacological Research Feb 2024Owing to the dysregulation of protein kinase activity in many diseases including cancer, this enzyme family has become one of the most important drug targets in the 21st... (Review)
Review
Owing to the dysregulation of protein kinase activity in many diseases including cancer, this enzyme family has become one of the most important drug targets in the 21st century. There are 80 FDA-approved therapeutic agents that target about two dozen different protein kinases and seven of these drugs were approved in 2023. Of the approved drugs, thirteen target protein-serine/threonine protein kinases, four are directed against dual specificity protein kinases (MEK1/2), twenty block nonreceptor protein-tyrosine kinases, and 43 inhibit receptor protein-tyrosine kinases. The data indicate that 69 of these drugs are prescribed for the treatment of neoplasms. Six drugs (abrocitinib, baricitinib, deucravacitinib, ritlecitinib, tofacitinib, upadacitinib) are used for the treatment of inflammatory diseases (atopic dermatitis, rheumatoid arthritis, psoriasis, alopecia areata, and ulcerative colitis). Of the 80 approved drugs, nearly two dozen are used in the treatment of multiple diseases. The following seven drugs received FDA approval in 2023: capivasertib (HER2-positive breast cancer), fruquintinib (metastatic colorectal cancer), momelotinib (myelofibrosis), pirtobrutinib (mantle cell lymphoma, chronic lymphocytic leukemia, small lymphocytic lymphoma), quizartinib (Flt3-mutant acute myelogenous leukemia), repotrectinib (ROS1-positive lung cancer), and ritlecitinib (alopecia areata). All of the FDA-approved drugs are orally effective with the exception of netarsudil, temsirolimus, and trilaciclib. This review summarizes the physicochemical properties of all 80 FDA-approved small molecule protein kinase inhibitors including the molecular weight, number of hydrogen bond donors/acceptors, polar surface area, potency, solubility, lipophilic efficiency, and ligand efficiency.
Topics: Humans; Adult; Protein Kinase Inhibitors; Alopecia Areata; Protein-Tyrosine Kinases; Proto-Oncogene Proteins; Protein Serine-Threonine Kinases; Protein Kinases; Neoplasms
PubMed: 38216005
DOI: 10.1016/j.phrs.2024.107059 -
Cell Metabolism Mar 2020The AMPK (AMP-activated protein kinase) and TOR (target-of-rapamycin) pathways are interlinked, opposing signaling pathways involved in sensing availability of nutrients... (Review)
Review
The AMPK (AMP-activated protein kinase) and TOR (target-of-rapamycin) pathways are interlinked, opposing signaling pathways involved in sensing availability of nutrients and energy and regulation of cell growth. AMPK (Yin, or the "dark side") is switched on by lack of energy or nutrients and inhibits cell growth, while TOR (Yang, or the "bright side") is switched on by nutrient availability and promotes cell growth. Genes encoding the AMPK and TOR complexes are found in almost all eukaryotes, suggesting that these pathways arose very early during eukaryotic evolution. During the development of multicellularity, an additional tier of cell-extrinsic growth control arose that is mediated by growth factors, but these often act by modulating nutrient uptake so that AMPK and TOR remain the underlying regulators of cellular growth control. In this review, we discuss the evolution, structure, and regulation of the AMPK and TOR pathways and the complex mechanisms by which they interact.
Topics: AMP-Activated Protein Kinases; Animals; Cell Proliferation; Cells; DNA Damage; Humans; Nutrients; TOR Serine-Threonine Kinases
PubMed: 32130880
DOI: 10.1016/j.cmet.2020.01.015 -
Nature Reviews. Drug Discovery Jan 2021Despite recent advances in the treatment of autoimmune and inflammatory diseases, unmet medical needs in some areas still exist. One of the main therapeutic approaches... (Review)
Review
Despite recent advances in the treatment of autoimmune and inflammatory diseases, unmet medical needs in some areas still exist. One of the main therapeutic approaches to alleviate dysregulated inflammation has been to target the activity of kinases that regulate production of inflammatory mediators. Small-molecule kinase inhibitors have the potential for broad efficacy, convenience and tissue penetrance, and thus often offer important advantages over biologics. However, designing kinase inhibitors with target selectivity and minimal off-target effects can be challenging. Nevertheless, immense progress has been made in advancing kinase inhibitors with desirable drug-like properties into the clinic, including inhibitors of JAKs, IRAK4, RIPKs, BTK, SYK and TPL2. This Review will address the latest discoveries around kinase inhibitors with an emphasis on clinically validated autoimmunity and inflammatory pathways.
Topics: Animals; Autoimmune Diseases; Autoimmunity; Humans; Inflammation; Protein Kinase Inhibitors; Protein Kinases
PubMed: 33077936
DOI: 10.1038/s41573-020-0082-8 -
International Journal of Molecular... Sep 2022Ca/calmodulin-dependent protein kinase kinase (CaMKK) is the activating kinase for multiple downstream kinases, including CaM-kinase I (CaMKI), CaM-kinase IV (CaMKIV),... (Review)
Review
Ca/calmodulin-dependent protein kinase kinase (CaMKK) is the activating kinase for multiple downstream kinases, including CaM-kinase I (CaMKI), CaM-kinase IV (CaMKIV), protein kinase B (PKB/Akt), and 5'AMP-kinase (AMPK), through the phosphorylation of their activation-loop Thr residues in response to increasing the intracellular Ca concentration, as CaMKK itself is a Ca/CaM-dependent enzyme. The CaMKK-mediated kinase cascade plays important roles in a number of Ca-dependent pathways, such as neuronal morphogenesis and plasticity, transcriptional activation, autophagy, and metabolic regulation, as well as in pathophysiological pathways, including cancer progression, metabolic syndrome, and mental disorders. This review focuses on the molecular mechanism underlying CaMKK-mediated signal transduction in normal and pathophysiological conditions. We summarize the current knowledge of the structural, functional, and physiological properties of the regulatory kinase, CaMKK, and the development and application of its pharmacological inhibitors.
Topics: AMP-Activated Protein Kinases; Adenosine Monophosphate; Calcium-Calmodulin-Dependent Protein Kinase Kinase; Calcium-Calmodulin-Dependent Protein Kinases; Humans; Phosphorylation; Proto-Oncogene Proteins c-akt; Signal Transduction
PubMed: 36232320
DOI: 10.3390/ijms231911025 -
Nature Reviews. Drug Discovery Jul 2019Since the discovery of AMP-activated protein kinase (AMPK) as a central regulator of energy homeostasis, many exciting insights into its structure, regulation and... (Review)
Review
Since the discovery of AMP-activated protein kinase (AMPK) as a central regulator of energy homeostasis, many exciting insights into its structure, regulation and physiological roles have been revealed. While exercise, caloric restriction, metformin and many natural products increase AMPK activity and exert a multitude of health benefits, developing direct activators of AMPK to elicit beneficial effects has been challenging. However, in recent years, direct AMPK activators have been identified and tested in preclinical models, and a small number have entered clinical trials. Despite these advances, which disease(s) represent the best indications for therapeutic AMPK activation and the long-term safety of such approaches remain to be established.
Topics: AMP-Activated Protein Kinases; Animals; Binding Sites; Carbohydrate Metabolism; Drug Development; Energy Metabolism; Humans; Lipid Metabolism; Protein Binding; Protein Conformation; Protein Isoforms; Signal Transduction; Small Molecule Libraries
PubMed: 30867601
DOI: 10.1038/s41573-019-0019-2 -
Molecular Cell Jul 2021Lipid droplets are important for cancer cell growth and survival. However, the mechanism underlying the initiation of lipid droplet lipolysis is not well understood. We...
Lipid droplets are important for cancer cell growth and survival. However, the mechanism underlying the initiation of lipid droplet lipolysis is not well understood. We demonstrate here that glucose deprivation induces the binding of choline kinase (CHK) α2 to lipid droplets, which is sequentially mediated by AMPK-dependent CHKα2 S279 phosphorylation and KAT5-dependent CHKα2 K247 acetylation. Importantly, CHKα2 with altered catalytic domain conformation functions as a protein kinase and phosphorylates PLIN2 at Y232 and PLIN3 at Y251. The phosphorylated PLIN2/3 dissociate from lipid droplets and are degraded by Hsc70-mediated autophagy, thereby promoting lipid droplet lipolysis, fatty acid oxidation, and brain tumor growth. In addition, levels of CHKα2 S279 phosphorylation, CHKα2 K247 acetylation, and PLIN2/3 phosphorylation are positively correlated with one another in human glioblastoma specimens and are associated with poor prognosis in glioblastoma patients. These findings underscore the role of CHKα2 as a protein kinase in lipolysis and glioblastoma development.
Topics: Acetylation; Cell Line, Tumor; Choline Kinase; Glioblastoma; Humans; Lipid Droplets; Lipolysis; Neoplasm Proteins; Protein Kinases
PubMed: 34077757
DOI: 10.1016/j.molcel.2021.05.005 -
Autophagy Mar 2022The eukaryotic-type protein kinase G (PknG), one of the eleven eukaryotic type serine-threonine protein kinase (STPK) in (Mtb), is involved in mycobacterial survival...
The eukaryotic-type protein kinase G (PknG), one of the eleven eukaryotic type serine-threonine protein kinase (STPK) in (Mtb), is involved in mycobacterial survival within macrophages, presumably by suppressing phagosome and autophagosome maturation, which makes PknG an attractive drug target. However, the exact mechanism by which PknG inhibits pathogen clearance during mycobacterial infection remains largely unknown. Here, we show that PknG promotes macroautophagy/autophagy induction but inhibits autophagosome maturation, causing an overall effect of blocked autophagy flux and enhanced pathogen intracellular survival. PknG prevents the activation of AKT (AKT serine/threonine kinase) via competitively binding to its pleckstrin homology (PH) domain, leading to autophagy induction. Remarkably, PknG could also inhibit autophagosome maturation to block autophagy flux via targeting host small GTPase RAB14. Specifically, PknG directly interacts with RAB14 to block RAB14-GTP hydrolysis. Furthermore, PknG phosphorylates TBC1D4/AS160 (TBC1 domain family member 4) to suppress its GTPase-activating protein (GAP) activity toward RAB14. In macrophages and , PknG promotes Mtb intracellular survival through blocking autophagy flux, which is dependent on RAB14. Taken together, our data unveil a dual-functional bacterial effector that tightly regulates host autophagy flux to benefit pathogen intracellular survival. AKT: AKT serine/threonine kinase; ATG5: autophagy related 5; BMDMs: bone marrow-derived macrophages; DTT: dithiothreitol; FBS: fetal calf serum; GAP: GTPase-activating protein; MOI: multiplicity of infection; Mtb: ; MTOR: mechanistic target of rapamycin kinase; OADC: oleic acid-albumin-dextrose-catalase; PC, phosphatidylcholine; PH: pleckstrin homology; PI3K: phosphoinositide 3-kinase; PknG: protein kinase G; PtdIns(3,4,5)P: phosphatidylinositol(3,4,5)-trisphosphate; SQSTM1: sequestosome 1; STPK: serine-threonine protein kinase; TB: tuberculosis; TBC1D4: TBC1 domain family member 4; TPR: tetratricopeptide repeat; ULK1: unc-51 like autophagy activating kinase 1; WT: wild-type.
Topics: Autophagy; Cyclic GMP-Dependent Protein Kinases; GTPase-Activating Proteins; Humans; Mycobacterium tuberculosis; Phosphatidylinositol 3-Kinases; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins c-akt; Serine; Tuberculosis; rab GTP-Binding Proteins
PubMed: 34092182
DOI: 10.1080/15548627.2021.1938912 -
Nature Reviews. Immunology Dec 2023Protein kinases play a major role in cellular activation processes, including signal transduction by diverse immunoreceptors. Given their roles in cell growth and death... (Review)
Review
Protein kinases play a major role in cellular activation processes, including signal transduction by diverse immunoreceptors. Given their roles in cell growth and death and in the production of inflammatory mediators, targeting kinases has proven to be an effective treatment strategy, initially as anticancer therapies, but shortly thereafter in immune-mediated diseases. Herein, we provide an overview of the status of small molecule inhibitors specifically generated to target protein kinases relevant to immune cell function, with an emphasis on those approved for the treatment of immune-mediated diseases. The development of inhibitors of Janus kinases that target cytokine receptor signalling has been a particularly active area, with Janus kinase inhibitors being approved for the treatment of multiple autoimmune and allergic diseases as well as COVID-19. In addition, TEC family kinase inhibitors (including Bruton's tyrosine kinase inhibitors) targeting antigen receptor signalling have been approved for haematological malignancies and graft versus host disease. This experience provides multiple important lessons regarding the importance (or not) of selectivity and the limits to which genetic information informs efficacy and safety. Many new agents are being generated, along with new approaches for targeting kinases.
Topics: Humans; Protein Kinases; Protein Kinase Inhibitors; Signal Transduction; Immune System Diseases
PubMed: 37188939
DOI: 10.1038/s41577-023-00877-7 -
Nature Communications Mar 2022Functioning as a master kinase, 3-phosphoinositide-dependent protein kinase 1 (PDK1) plays a fundamental role in phosphorylating and activating protein kinases A, B and...
Functioning as a master kinase, 3-phosphoinositide-dependent protein kinase 1 (PDK1) plays a fundamental role in phosphorylating and activating protein kinases A, B and C (AGC) family kinases, including AKT. However, upstream regulation of PDK1 remains largely elusive. Here we report that ribosomal protein S6 kinase beta 1 (S6K1), a member of AGC kinases and downstream target of mechanistic target of rapamycin complex 1 (mTORC1), directly phosphorylates PDK1 at its pleckstrin homology (PH) domain, and impairs PDK1 interaction with and activation of AKT. Mechanistically, S6K1-mediated phosphorylation of PDK1 augments its interaction with 14-3-3 adaptor protein and homo-dimerization, subsequently dissociating PDK1 from phosphatidylinositol 3,4,5 triphosphate (PIP) and retarding its interaction with AKT. Pathologically, tumor patient-associated PDK1 mutations, either attenuating S6K1-mediated PDK1 phosphorylation or impairing PDK1 interaction with 14-3-3, result in elevated AKT kinase activity and oncogenic functions. Taken together, our findings not only unravel a delicate feedback regulation of AKT signaling via S6K1-mediated PDK1 phosphorylation, but also highlight the potential strategy to combat mutant PDK1-driven cancers.
Topics: 3-Phosphoinositide-Dependent Protein Kinases; Humans; Phosphorylation; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins c-akt; Ribosomal Protein S6 Kinases, 70-kDa
PubMed: 35318320
DOI: 10.1038/s41467-022-28910-8