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Signal Transduction and Targeted Therapy Jan 2023Integrins are considered the main cell-adhesion transmembrane receptors that play multifaceted roles as extracellular matrix (ECM)-cytoskeletal linkers and transducers... (Review)
Review
Integrins are considered the main cell-adhesion transmembrane receptors that play multifaceted roles as extracellular matrix (ECM)-cytoskeletal linkers and transducers in biochemical and mechanical signals between cells and their environment in a wide range of states in health and diseases. Integrin functions are dependable on a delicate balance between active and inactive status via multiple mechanisms, including protein-protein interactions, conformational changes, and trafficking. Due to their exposure on the cell surface and sensitivity to the molecular blockade, integrins have been investigated as pharmacological targets for nearly 40 years, but given the complexity of integrins and sometimes opposite characteristics, targeting integrin therapeutics has been a challenge. To date, only seven drugs targeting integrins have been successfully marketed, including abciximab, eptifibatide, tirofiban, natalizumab, vedolizumab, lifitegrast, and carotegrast. Currently, there are approximately 90 kinds of integrin-based therapeutic drugs or imaging agents in clinical studies, including small molecules, antibodies, synthetic mimic peptides, antibody-drug conjugates (ADCs), chimeric antigen receptor (CAR) T-cell therapy, imaging agents, etc. A serious lesson from past integrin drug discovery and research efforts is that successes rely on both a deep understanding of integrin-regulatory mechanisms and unmet clinical needs. Herein, we provide a systematic and complete review of all integrin family members and integrin-mediated downstream signal transduction to highlight ongoing efforts to develop new therapies/diagnoses from bench to clinic. In addition, we further discuss the trend of drug development, how to improve the success rate of clinical trials targeting integrin therapies, and the key points for clinical research, basic research, and translational research.
Topics: Integrins; Cell Adhesion; Cell Communication; Signal Transduction; Peptides
PubMed: 36588107
DOI: 10.1038/s41392-022-01259-6 -
Journal of Clinical Medicine Jul 2020Drug-induced immune thrombocytopenia (DITP) is a life-threatening clinical syndrome that is under-recognized and difficult to diagnose. Many drugs can cause... (Review)
Review
Drug-induced immune thrombocytopenia (DITP) is a life-threatening clinical syndrome that is under-recognized and difficult to diagnose. Many drugs can cause immune-mediated thrombocytopenia, but the most commonly implicated are abciximab, carbamazepine, ceftriaxone, eptifibatide, heparin, ibuprofen, mirtazapine, oxaliplatin, penicillin, quinine, quinidine, rifampicin, suramin, tirofiban, trimethoprim-sulfamethoxazole, and vancomycin. Several different mechanisms have been identified in typical DITP, which is most commonly characterized by severe thrombocytopenia due to clearance and/or destruction of platelets sensitized by a drug-dependent antibody. Patients with typical DITP usually bleed when symptomatic, and biological confirmation of the diagnosis is often difficult because detection of drug-dependent antibodies (DDabs) in the patient's serum or plasma is frequently not possible. This is in contrast to heparin-induced thrombocytopenia (HIT), which is a particular DITP caused in most cases by heparin-dependent antibodies specific for platelet factor 4, which can strongly activate platelets in vitro and in vivo, explaining why affected patients usually have thrombotic complications but do not bleed. In addition, laboratory tests are readily available to diagnose HIT, unlike the methods used to detect DDabs associated with other DITP that are mostly reserved for laboratories specialized in platelet immunology.
PubMed: 32668640
DOI: 10.3390/jcm9072212 -
Journal of Hematology & Oncology Mar 2019Integrins are a family of transmembrane glycoprotein signaling receptors that can transmit bioinformation bidirectionally across the plasma membrane. Integrin αIIbβ3... (Review)
Review
Integrins are a family of transmembrane glycoprotein signaling receptors that can transmit bioinformation bidirectionally across the plasma membrane. Integrin αIIbβ3 is expressed at a high level in platelets and their progenitors, where it plays a central role in platelet functions, hemostasis, and arterial thrombosis. Integrin αIIbβ3 also participates in cancer progression, such as tumor cell proliferation and metastasis. In resting platelets, integrin αIIbβ3 adopts an inactive conformation. Upon agonist stimulation, the transduction of inside-out signals leads integrin αIIbβ3 to switch from a low- to high-affinity state for fibrinogen and other ligands. Ligand binding causes integrin clustering and subsequently promotes outside-in signaling, which initiates and amplifies a range of cellular events to drive essential platelet functions such as spreading, aggregation, clot retraction, and thrombus consolidation. Regulation of the bidirectional signaling of integrin αIIbβ3 requires the involvement of numerous interacting proteins, which associate with the cytoplasmic tails of αIIbβ3 in particular. Integrin αIIbβ3 and its signaling pathways are considered promising targets for antithrombotic therapy. This review describes the bidirectional signal transduction of integrin αIIbβ3 in platelets, as well as the proteins responsible for its regulation and therapeutic agents that target integrin αIIbβ3 and its signaling pathways.
Topics: Abciximab; Amino Acid Sequence; Animals; Blood Platelets; Eptifibatide; Humans; Molecular Targeted Therapy; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Signal Transduction; Tirofiban
PubMed: 30845955
DOI: 10.1186/s13045-019-0709-6 -
EuroIntervention : Journal of EuroPCR... May 2014Optimal perioperative antiplatelet therapy in patients with coronary stents undergoing surgery still remains poorly defined and a matter of debate among cardiologists,...
Perioperative management of antiplatelet therapy in patients with coronary stents undergoing cardiac and non-cardiac surgery: a consensus document from Italian cardiological, surgical and anaesthesiological societies.
Optimal perioperative antiplatelet therapy in patients with coronary stents undergoing surgery still remains poorly defined and a matter of debate among cardiologists, surgeons and anaesthesiologists. Surgery represents one of the most common reasons for premature antiplatelet therapy discontinuation, which is associated with a significant increase in mortality and major adverse cardiac events, in particular stent thrombosis. Clinical practice guidelines provide little support with regard to managing antiplatelet therapy in the perioperative phase in the case of patients with non-deferrable surgical interventions and/or high haemorrhagic risk. Moreover, a standard definition of ischaemic and haemorrhagic risk has never been determined. Finally, recommendations shared by cardiologists, surgeons and anaesthesiologists are lacking. The present consensus document provides practical recommendations on the perioperative management of antiplatelet therapy in patients with coronary stents undergoing surgery. Cardiologists, surgeons and anaesthesiologists have contributed equally to its creation. On the basis of clinical and angiographic data, the individual thrombotic risk has been defined. All surgical interventions have been classified according to their inherent haemorrhagic risk. A consensus on the optimal antiplatelet regimen in the perioperative phase has been reached on the basis of the ischaemic and haemorrhagic risk. Aspirin should be continued perioperatively in the majority of surgical operations, whereas dual antiplatelet therapy should not be withdrawn for surgery in the case of low bleeding risk. In selected patients at high risk for both bleeding and ischaemic events, when oral antiplatelet therapy withdrawal is required, perioperative treatment with short-acting intravenous glycoprotein IIb/IIIa inhibitors (tirofiban or eptifibatide) should be taken into consideration.
Topics: Anesthesiology; Aspirin; Cardiac Surgical Procedures; Cardiology; Clopidogrel; Eptifibatide; Hemorrhage; Humans; Italy; Myocardial Ischemia; Peptides; Perioperative Care; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Risk Assessment; Societies, Medical; Stents; Surgical Procedures, Operative; Thoracic Surgery; Ticlopidine; Tirofiban; Tyrosine
PubMed: 24832636
DOI: 10.4244/EIJV10I1A8 -
Angewandte Chemie (International Ed. in... Sep 2021Cells transmit piconewton forces to receptors to mediate processes such as migration and immune recognition. A major challenge in quantifying such forces is the sparsity...
Cells transmit piconewton forces to receptors to mediate processes such as migration and immune recognition. A major challenge in quantifying such forces is the sparsity of cell mechanical events. Accordingly, molecular tension is typically quantified with high resolution fluorescence microscopy, which hinders widespread adoption and application. Here, we report a mechanically triggered hybridization chain reaction (mechano-HCR) that allows chemical amplification of mechanical events. The amplification is triggered when a cell receptor mechanically denatures a duplex revealing a cryptic initiator to activate the HCR reaction in situ. Importantly, mechano-HCR enables direct readout of pN forces using a plate reader. We leverage this capability and measured mechano-IC for aspirin, Y-27632, and eptifibatide. Given that cell mechanical phenotypes are of clinical importance, mechano-HCR may offer a convenient route for drug discovery, personalized medicine, and disease diagnosis.
Topics: Aspirin; Eptifibatide; Humans; Nucleic Acid Hybridization
PubMed: 34242462
DOI: 10.1002/anie.202107660 -
Journal of Hematology & Oncology Nov 2011Anti-platelet therapy plays an important role in the treatment of patients with thrombotic diseases. The most commonly used anti-platelet drugs, namely, aspirin,... (Review)
Review
Anti-platelet therapy plays an important role in the treatment of patients with thrombotic diseases. The most commonly used anti-platelet drugs, namely, aspirin, ticlopidine, and clopidogrel, are effective in the prevention and treatment of cardio-cerebrovascular diseases. Glycoprotein IIb/IIIa antagonists (e.g., abciximab, eptifibatide and tirofiban) have demonstrated good clinical benefits and safety profiles in decreasing ischemic events in acute coronary syndrome. However, adverse events related to thrombosis or bleeding have been reported in cases of therapy with glycoprotein IIb/IIIa antagonists. Cilostazol is an anti-platelet agent used in the treatment of patients with peripheral ischemia, such as intermittent claudication. Presently, platelet adenosine diphosphate P2Y(12) receptor antagonists (e.g., clopidogrel, prasugrel, cangrelor, and ticagrelor) are being used in clinical settings for their pronounced protective effects. The new protease-activated receptor antagonists, vorapaxar and atopaxar, potentially decrease the risk of ischemic events without significantly increasing the rate of bleeding. Some other new anti-platelet drugs undergoing clinical trials have also been introduced. Indeed, the number of new anti-platelet drugs is increasing. Consequently, the efficacy of these anti-platelet agents in actual patients warrants scrutiny, especially in terms of the hemorrhagic risks. Hopefully, new selective platelet inhibitors with high anti-thrombotic efficiencies and low hemorrhagic side effects can be developed.
Topics: Humans; Platelet Aggregation Inhibitors; Thrombosis
PubMed: 22053759
DOI: 10.1186/1756-8722-4-44