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1.
Angew Chem Int Ed Engl ; : e202418081, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39363693

RESUMO

Immunotherapy is a promising cancer treatment method for eradicating tumor cells by enhancing the immune response. However, there are several major obstacles to conventional phototherapy-mediated immune responses, including inadequate immunogenicity and immunosuppressive environment. Here, we present a novel photoimmunotherapy modality-the development of membrane-anchoring small molecule inducing plasma membrane rupture (PMR) by NIR-II photo-stimulation, thus evoking cell necrotic death and enhancing antitumor immunotherapy. Our top-performing membrane-anchoring small molecule (CBT-3) exhibits temperature-tunable PMR efficiency, allowing rapid necrotic death in cancer cells at 50 µM dose by using exogenous NIR-II light-mediated mild photothermal effect (1064 nm, 0.6 W cm-2). Further evidence indicated that this gentle therapeutic approach activated inflammatory signaling pathways in cells, enhanced immunogenic cell death, and reshaped the immunosuppressive tumor microenvironment, ultimately promoting systemic antitumor immune responses in vivo. This study represents the first instance of utilizing NIR-II photo-amplified PMR effect based on membrane-anchoring small molecule, providing a novel avenue for advancing cancer photoimmunotherapy.

2.
Angew Chem Int Ed Engl ; 63(9): e202312755, 2024 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-38195886

RESUMO

Controlling the nanoparticle-cell membrane interaction to achieve easy and fast membrane anchoring and cellular internalization is of great importance in a variety of biomedical applications. Here we report a simple and versatile strategy to maneuver the nanoparticle-cell membrane interaction by creating a tunable hydrophobic protrusion on Janus particles through swelling-induced symmetry breaking. When the Janus particle contacts cell membrane, the protrusion will induce membrane wrapping, leading the particles to docking to the membrane, followed by drawing the whole particles into the cell. The efficiencies of both membrane anchoring and cellular internalization can be promoted by optimizing the size of the protrusion. In vitro, the Janus particles can quickly anchor to the cell membrane in 1 h and be internalized within 24 h, regardless of the types of cells involved. In vivo, the Janus particles can effectively anchor to the brain and skin tissues to provide a high retention in these tissues after intracerebroventricular, intrahippocampal, or subcutaneous injection. This strategy involving the creation of a hydrophobic protrusion on Janus particles to tune the cell-membrane interaction holds great potential in nanoparticle-based biomedical applications.


Assuntos
Nanopartículas Multifuncionais , Nanopartículas , Nanopartículas/química , Membrana Celular/metabolismo , Interações Hidrofóbicas e Hidrofílicas
3.
Chembiochem ; 23(11): e202100637, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35352864

RESUMO

The promise of personalized medicine for monogenic and complex polygenic diseases depends on the availability of strategies for targeted inhibition of disease-associated polymorphic protein variants. Loss of function variants, including non-synonymous single nucleotide variants (nsSNVs) and insertion/deletion producing a frameshift, account for the vast majority of disease-related genetic changes. Because it is challenging to interpret the functional consequences of nsSNVs, they are considered a big barrier for personalized medicine. A method for inhibiting the specific expression of nsSNVs without editing the human genome will facilitate the elucidation of the biology of nsSNVs, but such a method is currently lacking. Here, I describe the phenomenon of membrane anchorage-induced (MAGIC) knockdown of allele-specific inhibition of protein and mRNA expression upon inner membrane tethering of point mutation-specific monoclonal antibodies (mAb). This phenomenon is likely mediated by a mechanism distinct from the protein degradation pathways, as the epitope-specific knockdown is replicated upon intracellular expression of a membrane-anchored single domain intrabody that lacks the Fc domain of the mAb. By harnessing the MAGIC knockdown of epitope-containing protein targets, I report a novel approach for inhibiting the expression of amino-acid-altering germline and somatic nsSNVs. As a proof-of-concept, I show the inhibition of human disease-associated variants namely, FGFR4 p.G388R, KRAS p.G12D and BRAF p.V600E protein variants. This method opens up a new avenue for not just therapeutic suppression of undruggable protein variants, but also for functional interrogation of the nsSNVs of unknown significance.


Assuntos
Mutação Puntual , Polimorfismo de Nucleotídeo Único , Epitopos , Genoma Humano , Humanos , Medicina de Precisão
4.
Angew Chem Int Ed Engl ; 61(11): e202113795, 2022 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-34990055

RESUMO

Systematic interrogation of correlative signaling components in their native environment is of great interest for dissecting sophisticated cellular signaling. However, it remains a challenge because of the lack of versatile and effective approaches. Herein, we propose a cell membrane-anchored DNA multitasking processor acting as a "traffic light" for integrated analyses of cellular signal transduction. Enhanced and controllable inhibition of c-Met signaling was achieved by membrane-anchoring of DNA processors. Moreover, the multitasking capability of the DNA processor allowed the monitoring of correlative VEGF secretion induced by c-Met activity regulation directly. By exploiting versatile aptameric nucleic acids, this modular designed DNA multitasking processor dissected how cell surface receptors coordinated with related components in live cells systematically. Therefore, it provides a powerful chemical tool for both fundamental cell biology research and precision medicine applications.


Assuntos
Membrana Celular/metabolismo , DNA/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular Tumoral , Membrana Celular/química , DNA/química , Humanos , Proteínas Proto-Oncogênicas c-met/química , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/química
5.
Angew Chem Int Ed Engl ; 60(16): 9093-9098, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33543534

RESUMO

Pyroptosis as a lytic and inflammatory form of cell death is a powerful tool to fight against cancer. However, pyroptosis is usually activated by chemotherapeutic drugs, which limits its anti-tumor applications due to drug resistance and severe side effects. Herein, we demonstrate that membrane targeting photosensitizers can induce pyroptosis for cancer cell ablation with noninvasiveness and low side effects. A series of membrane anchoring photosensitizers (TBD-R PSs) with aggregation-induced emission (AIE) characteristics were prepared through conjugation of TBD and phenyl ring with cationic chains. Upon light irradiation, cytotoxic ROS were produced in situ, resulting in direct membrane damage and superior cancer cell ablation. Detailed study revealed that pyroptosis gradually became the dominant cell death pathway along with the increase of TBD-R PSs membrane anchoring capability. This study offers a photo-activated pyroptosis-based intervention strategy for cancer cell ablation.


Assuntos
Antineoplásicos/farmacologia , Nitrilas/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Piroptose/efeitos dos fármacos , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Nitrilas/síntese química , Nitrilas/química , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Espécies Reativas de Oxigênio/metabolismo
6.
IUBMB Life ; 72(8): 1649-1658, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32255257

RESUMO

Adoptive cell therapy using patients' own T-cells is expected to be an ideal cancer treatment strategy with excellent antitumor effects and low side effects. However, this therapy targeting solid tumors is unlikely to be effective because tumor tissues have an environment that suppresses T-cell function. In particular, interaction between programmed death-1 (PD-1) and its ligand (PD-L1) inhibits T-cell activation by which T-cells eliminate tumor cells. Here, we attempted to develop T-cells that can exert potent antitumor activity even in tumor tissues by genetically modifying them to express the anti-PD-L1 membrane-anchoring type single chain variable fragment (M-scFv) that can inhibit PD-L1/PD-1 interaction. Anti-PD-L1 M-scFv could be expressed on T-cells while maintaining PD-L1-binding ability. Although T-cell proliferation induced by CD3 stimulation was decreased depending on the PD-L1 stimulation intensity, M-scFv-expressing T-cells showed high proliferative activity even in the presence of PD-L1 by avoiding the PD-L1/PD-1-mediated suppression. Furthermore, M-scFv-expressing T-cells showed higher cytotoxic activity against PD-L1high tumor cells than that of mock T-cells. The effect of PD-L1/PD-1 blockade was more pronounced when the therapeutic target was low-antigenic tumor cells with low major histocompatibility complex expression, presenting only the shared antigen. These results indicated that anti-PD-L1 M-scFv expression was functional in avoiding T-cell dysfunction by PD-L1/PD-1 interaction. Our concept of anti-PD-L1 M-scFv-expressing T-cells is thus expected to improve the efficacy of T-cell therapy and contribute to simplify the treatment system and reduce treatment costs compared with the combination therapy of T-cells and antibodies.


Assuntos
Antígeno B7-H1/imunologia , Inibidores de Checkpoint Imunológico/farmacologia , Melanoma Experimental/terapia , Receptor de Morte Celular Programada 1/imunologia , Animais , Antineoplásicos/imunologia , Antineoplásicos/farmacologia , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/genética , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Imunoterapia Adotiva , Ativação Linfocitária , Melanoma Experimental/genética , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/genética , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
7.
Can J Physiol Pharmacol ; 98(7): 473-476, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32017610

RESUMO

Acetylcholine (ACh)-mediated vagal transmission as well as nonneuronal ACh release are considered cardioprotective in pathological situations with increased sympathetic drive such as ischemia-reperfusion and cardiac remodeling. ACh action is terminated by hydrolysis by the cholinesterases (ChEs), acetylcholinesterase, and butyrylcholinesterase. Both ChEs exist in multiple molecular variants either soluble or anchored by specific anchoring proteins like collagen Q (ColQ) anchoring protein and proline-rich membrane anchoring protein (PRiMA). Here we assessed the expression of specific ChE molecular forms in different heart compartments using RT-qPCR. We show that both ChEs are expressed in all heart compartments but display different expression patterns. The acetylcholinesterase-T variant together with PRiMA and ColQ is predominantly expressed in rat atria. Butylcholinesterase is found in all heart compartments and is accompanied by both PRiMA and ColQ anchors. Its expression in the ventricular system suggests involvement in the nonneuronal cholinergic system. Additionally, two PRiMA variants are detected throughout the rat heart.


Assuntos
Acetilcolina/metabolismo , Acetilcolinesterase/análise , Butirilcolinesterase/análise , Miocárdio/enzimologia , Acetilcolinesterase/metabolismo , Animais , Butirilcolinesterase/metabolismo , Colágeno/análise , Colágeno/metabolismo , Proteínas Ligadas por GPI/análise , Proteínas Ligadas por GPI/metabolismo , Perfilação da Expressão Gênica , Isoenzimas/análise , Isoenzimas/metabolismo , Masculino , Proteínas de Membrana/análise , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real
8.
Development ; 143(9): 1491-501, 2016 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-26965371

RESUMO

Defects in cilia centrosomal genes cause pleiotropic clinical phenotypes, collectively called ciliopathies. Cilia biogenesis is initiated by the interaction of positive and negative regulators. Centriolar coiled coil protein 110 (CP110) caps the distal end of the mother centriole and is known to act as a suppressor to control the timing of ciliogenesis. Here, we demonstrate that CP110 promotes cilia formation in vivo, in contrast to findings in cultured cells. Cp110(-/-) mice die shortly after birth owing to organogenesis defects as in ciliopathies. Shh signaling is impaired in null embryos and primary cilia are reduced in multiple tissues. We show that CP110 is required for anchoring of basal bodies to the membrane during cilia formation. CP110 loss resulted in an abnormal distribution of core components of subdistal appendages (SDAs) and of recycling endosomes, which may be associated with premature extension of axonemal microtubules. Our data implicate CP110 in SDA assembly and ciliary vesicle docking, two requisite early steps in cilia formation. We suggest that CP110 has unique context-dependent functions, acting as both a suppressor and a promoter of ciliogenesis.


Assuntos
Proteínas de Ligação a Calmodulina/metabolismo , Centríolos/fisiologia , Cílios/fisiologia , Organogênese/fisiologia , Animais , Axonema/metabolismo , Corpos Basais/metabolismo , Proteínas de Ligação a Calmodulina/genética , Linhagem Celular , Centrossomo/metabolismo , Endossomos/metabolismo , Proteínas Hedgehog/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microtúbulos/metabolismo , Organogênese/genética
9.
J Struct Biol ; 204(3): 435-448, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30336202

RESUMO

Structural characterization of BMAP-28(1-18), a potent bovine myeloid antimicrobial peptide can aid in understanding its mechanism of action at molecular level. We report NMR structure of the BMAP-28(1-18) and its mutated analogue mutBMAP18 in SDS micelles. Structural comparison of the peptides bound to SDS micelles and POPE-POPG vesicles using circular dichroism, suggest that structures in the two lipid preparations are similar. Antimicrobial assays show that even though both these peptides adopt helical conformation, BMAP-28(1-18) is more potent than mutBMAP18 in killing bacterial cells. Our EM images clearly indicate that the peptides target the bacterial cell membrane resulting in leakage of its contents. The structural basis for difference in activity between these peptides was investigated by molecular dynamics simulations. Inability of the mutBMAP18 to retain its helical structure in presence of POPE:POPG membrane as opposed to the BMAP-28(1-18) at identical peptide/lipid ratios could be responsible for its decreased activity. Residues Ser5, Arg8 and Arg12 of the BMAP-28(1-18) are crucial for its initial anchoring to the bilayer. We conclude that along with amphipathicity, a stable secondary structure that can promote/initiate membrane anchoring is key in determining membrane destabilization potential of these AMPs. Our findings are a step towards understanding the role of specific residues in antimicrobial activity of BMAP-28(1-18), which will facilitate design of smaller, cost-effective therapeutics and would also help prediction algorithms to expedite screening out variants of the parent peptide with greater accuracy.


Assuntos
Anti-Infecciosos/química , Bactérias/metabolismo , Membrana Celular/metabolismo , Proteínas/química , Sequência de Aminoácidos , Animais , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Bovinos , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Dicroísmo Circular , Micelas , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Simulação de Dinâmica Molecular , Estrutura Secundária de Proteína , Proteínas/metabolismo , Proteínas/farmacologia , Homologia de Sequência de Aminoácidos , Dodecilsulfato de Sódio/química , Dodecilsulfato de Sódio/metabolismo
10.
Neurobiol Dis ; 78: 77-87, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25766677

RESUMO

Among the mechanisms underlying the development of L-dopa-induced dyskinesia (LID) in Parkinson's disease, complex alterations in dopamine signaling in D1 receptor (D1R)-expressing medium spiny striatal neurons have been unraveled such as, but not limited to, dysregulation of D1R expression, lateral diffusion, intraneuronal trafficking, subcellular localization and desensitization, leading to a pathological anchorage of D1R at the plasma membrane. Such anchorage is partly due to a decreased proteasomal activity that is specific of the L-dopa-exposed dopamine-depleted striatum, results from D1R activation and feeds-back the D1R exaggerated cell surface abundance. The precise mechanisms by which L-dopa affects striatal proteasome activity remained however unknown. We here show, in a series of in vitro ex vivo and in vivo models, that such rapid modulation of striatal proteasome activity intervenes through D1R-mediated disassembly of the 26S proteasome rather than change in transcription or translation of proteasome or proteasome subunits intraneuronal relocalization.


Assuntos
Corpo Estriado/enzimologia , Transtornos Parkinsonianos/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Receptores de Dopamina D1/metabolismo , Animais , Benzazepinas/farmacologia , Células Cultivadas , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Agonistas de Dopamina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Transtornos Parkinsonianos/enzimologia , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Ratos Sprague-Dawley
11.
J Neurosci ; 33(49): 19284-94, 2013 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-24305824

RESUMO

Pathological, genetic, and biochemical hallmarks of Alzheimer's disease (AD) are linked to amyloid-ß (Aß) peptide aggregation. Especially misfolded Aß42 peptide is sufficient to promote amyloid plaque formation. However, the cellular compartment facilitating the conversion of monomeric Aß to aggregated toxic Aß species remains unknown. In vitro models suggest lipid membranes to be the driving force of Aß conversion. To this end, we generated two novel mouse models, expressing either membrane-anchored or nonanchored versions of the human Aß42 peptide. Strikingly, membrane-anchored Aß42 robustly accelerated Aß deposition and exacerbated amyloid-associated toxicity upon crossing with Aß precursor protein transgenic mice. These in vivo findings support the hypothesis that Aß-membrane interactions play a pivotal role in early-onset AD as well as neuronal damage and provide evidence to study Aß-membrane interactions as therapeutic targets.


Assuntos
Peptídeos beta-Amiloides/farmacologia , Peptídeos beta-Amiloides/toxicidade , Placa Amiloide/patologia , Peptídeos beta-Amiloides/genética , Animais , Benzotiazóis , Biotinilação , Western Blotting , Membrana Celular/metabolismo , Membrana Celular/patologia , Endopeptidase K/química , Corantes Fluorescentes , Células HEK293 , Humanos , Imuno-Histoquímica , Inflamação/patologia , Camundongos , Camundongos Endogâmicos C57BL , Fosfatidilinositóis , Tiazóis , Fosfolipases Tipo C/química
12.
Biomaterials ; 307: 122536, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38522327

RESUMO

Antibacterial photodynamic therapy (aPDT) has emerged as a promising strategy for treating periodontitis. However, the weak binding of most photosensitizers to bacteria and the hypoxic environment of periodontal pockets severely hamper the therapeutic efficacy. Herein, two novel oxygen-independent photosensitizers are developed by introducing selenophene into viologens and modifying with hexane chains (HASeV) or quaternary ammonium chains (QASeV), which improve the adsorption to bacteria through anchoring to the negatively charged cell membrane. Notably, QASeV binds only to the bacterial surface of Porphyromonas gingivalis and Fusobacterium nucleatum due to electrostatic binding, but HASeV can insert into their membrane by strong hydrophobic interactions. Therefore, HASeV exhibits superior antimicrobial activity and more pronounced plaque biofilm disruption than QASeV when combined with light irradiation (MVL-210 photoreactor, 350-600 nm, 50 mW/cm2), and a better effect on reducing the diversity and restoring the structure of subgingival flora in periodontitis rat model was found through 16S rRNA gene sequencing analysis. The histological and Micro-CT analyses reveal that HASeV-based aPDT has a better therapeutic effect in reducing periodontal tissue inflammation and alveolar bone resorption. This work provides a new strategy for the development of viologen-based photosensitizers, which may be a favorable candidate for the aPDT against periodontitis.


Assuntos
Periodontite , Fotoquimioterapia , Animais , Ratos , Fármacos Fotossensibilizantes/uso terapêutico , RNA Ribossômico 16S , Periodontite/tratamento farmacológico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Inflamação/tratamento farmacológico , Bactérias , Porphyromonas gingivalis
14.
Front Immunol ; 15: 1307546, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38361945

RESUMO

Zika virus (ZIKV) is a re-emerging pathogen with high morbidity associated to congenital infection. Despite the scientific advances since the last outbreak in the Americas, there are no approved specific treatment or vaccines. As the development of an effective prophylactic approach remains unaddressed, DNA vaccines surge as a powerful and attractive candidate due to the efficacy of sequence optimization in achieving strong immune response. In this study, we developed four DNA vaccine constructs encoding the ZIKV prM/M (pre-membrane/membrane) and E (envelope) proteins in conjunction with molecular adjuvants. The DNA vaccine candidate (called ZK_ΔSTP), where the entire membrane-anchoring regions were completely removed, was far more immunogenic compared to their counterparts. Furthermore, inclusion of the tPA-SP leader sequence led to high expression and secretion of the target vaccine antigens, therefore contributing to adequate B cell stimulation. The ZK_ΔSTP vaccine induced high cellular and humoral response in C57BL/6 adult mice, which included high neutralizing antibody titers and the generation of germinal center B cells. Administration of ZK-ΔSTP incorporating aluminum hydroxide (Alum) adjuvant led to sustained neutralizing response. In consistency with the high and long-term protective response, ZK_ΔSTP+Alum protected adult mice upon viral challenge. Collectively, the ZK_ΔSTP+Alum vaccine formulation advances the understanding of the requirements for a successful and protective vaccine against flaviviruses and is worthy of further translational studies.


Assuntos
Compostos de Alúmen , Vacinas de DNA , Vacinas Virais , Infecção por Zika virus , Zika virus , Animais , Camundongos , Zika virus/genética , Anticorpos Neutralizantes , Anticorpos Antivirais , Proteínas do Envelope Viral/genética , Camundongos Endogâmicos C57BL , Adjuvantes Imunológicos , Adjuvantes Farmacêuticos
15.
Adv Sci (Weinh) ; 11(14): e2306936, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38298088

RESUMO

PtII based organometallic photosensitizers (PSs) have emerged as novel potent photodynamic inactivation (PDI) reagents through their enhanced intersystem crossing (ISC) processes. Currently, few PtII PSs have been investigated as antibacterial materials, with relatively poor performances reported and with structure-activity relationships not well described. Herein, a pair of configurational isomers are reported of Bis-BODIPY (4,4-difluoro-boradizaindacene) embedded PtII PSs. The cis-isomer (cis-BBP) displayed enhanced 1O2 generation and better bacterial membrane anchoring capability as compared to the trans-isomer (trans-BBP). The effective PDI concentrations (efficiency > 99.9%) for cis-BBP in Acinetobacter baumannii (multi-drug resistant (MDR)) and Staphylococcus aureus are 400 nM (12 J cm-2) and 100 nM (18 J cm-2), respectively; corresponding concentrations and light doses for trans-BBP in the two bacteria are 2.50 µM (30 J cm-2) and 1.50 µM (18 J cm-2), respectively. The 50% and 90% minimum inhibitory concentration (MIC50 and MIC90) ratio of trans-BBP to cis-BBP is 22.22 and 24.02 in A. baumannii (MDR); 21.29 and 22.36 in methicillin resistant S. aureus (MRSA), respectively. Furthermore, cis-BBP displays superior in vivo antibacterial performance, with acceptable dark and photoinduced cytotoxicity. These results demonstrate cis-BBP is a robust light-assisted antibacterial reagent at sub-micromolecular concentrations. More importantly, configuration of PtII PSs should be an important issue to be considered in further PDI reagents design.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Fármacos Fotossensibilizantes/farmacologia , Relação Estrutura-Atividade , Antibacterianos/farmacologia
16.
Curr Res Struct Biol ; 7: 100149, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38766652

RESUMO

Anchoring of coagulation factors to anionic regions of the membrane involves the C2 domain as a key player. The rate of enzymatic reactions of the coagulation factors is increased by several orders of magnitude upon membrane binding. However, the precise mechanisms behind the rate acceleration remain unclear, primarily because of a lack of understanding of the conformational dynamics of the C2-containing factors and corresponding complexes. We elucidate the membrane-bound form of the C2 domain from human coagulation factor V (FV-C2) by characterizing its membrane binding the specific lipid-protein interactions. Employing all-atom molecular dynamics simulations and leveraging the highly mobile membrane-mimetic (HMMM) model, we observed spontaneous binding of FV-C2 to a phosphatidylserine (PS)-containing membrane within 2-25 ns across twelve independent simulations. FV-C2 interacted with the membrane through three loops (spikes 1-3), achieving a converged, stable orientation. Multiple HMMM trajectories of the spontaneous membrane binding provided extensive sampling and ample data to examine the membrane-induced effects on the conformational dynamics of C2 as well as specific lipid-protein interactions. Despite existing crystal structures representing presumed "open" and "closed" states of FV-C2, our results revealed a continuous distribution of structures between these states, with the most populated structures differing from both "open" and "closed" states observed in crystal environments. Lastly, we characterized a putative PS-specific binding site formed by K23, Q48, and S78 located in the groove enclosed by spikes 1-3 (PS-specificity pocket), suggesting a different orientation of a bound headgroup moiety compared to previous proposals based upon analysis of static crystal structures.

17.
Expert Opin Drug Discov ; : 1-21, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39105536

RESUMO

INTRODUCTION: Molecular Dynamics (MD) simulations can support mechanism-based drug design. Indeed, MD simulations by capturing biomolecule motions at finite temperatures can reveal hidden binding sites, accurately predict drug-binding poses, and estimate the thermodynamics and kinetics, crucial information for drug discovery campaigns. Small-Guanosine Triphosphate Phosphohydrolases (GTPases) regulate a cascade of signaling events, that affect most cellular processes. Their deregulation is linked to several diseases, making them appealing drug targets. The broad roles of small-GTPases in cellular processes and the recent approval of a covalent KRas inhibitor as an anticancer agent renewed the interest in targeting small-GTPase with small molecules. AREA COVERED: This review emphasizes the role of MD simulations in elucidating small-GTPase mechanisms, assessing the impact of cancer-related variants, and discovering novel inhibitors. EXPERT OPINION: The application of MD simulations to small-GTPases exemplifies the role of MD simulations in the structure-based drug design process for challenging biomolecular targets. Furthermore, AI and machine learning-enhanced MD simulations, coupled with the upcoming power of quantum computing, are promising instruments to target elusive small-GTPases mutations and splice variants. This powerful synergy will aid in developing innovative therapeutic strategies associated to small-GTPases deregulation, which could potentially be used for personalized therapies and in a tissue-agnostic manner to treat tumors with mutations in small-GTPases.

18.
Adv Sci (Weinh) ; 10(28): e2302422, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37544896

RESUMO

Prostate cancer (PCa) is a frustrating immunogenic "cold" tumor and generally receives unsatisfied immunotherapy outcomes in the clinic. Pyroptosis is an excellent immunogenic cell death form that can effectively activate the antitumor immune response, promote cytotoxic T-lymphocyte infiltration, and convert tumors from "cold" to "hot." However, the in vivo application of pyroptosis drugs is seriously limited, and the upregulation of tumor PD-L1 caused by photo-immunotherapy further promotes immune escape. Herein, a new nano-photosensitizer (YBS-BMS NPs-RKC) with pH-response integrating immunogenic pyroptosis induction and immune checkpoint blockade is developed. The pH-responsive polymer equipped with the cell membrane anchoring peptide RKC is used as the carrier and further encapsulated with the near-infrared-activated semiconductor polymer photosensitizer YBS and a PD-1/PD-L1 complex small molecule inhibitor BMS-202. The pH-driven membrane-anchoring and pyroptosis activation of YBS-BMS NPs-RKC is clearly demonstrated. In vitro and in vivo studies have shown that this dual-pronged therapy stimulates a powerful antitumor immune response to suppress primary tumor progression and evokes long-term immune memory to inhibit tumor relapse and metastasis. This work provides an effective self-synergistic platform for PCa immunotherapy and a new idea for developing more biocompatible photo-controlled pyroptosis inducers.


Assuntos
Antígeno B7-H1 , Neoplasias da Próstata , Masculino , Humanos , Fármacos Fotossensibilizantes , Piroptose , Recidiva Local de Neoplasia , Neoplasias da Próstata/tratamento farmacológico , Imunoterapia , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Polímeros , Concentração de Íons de Hidrogênio
19.
Adv Healthc Mater ; 12(21): e2300102, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36988195

RESUMO

Cell signal transduction mediated by cell surface ligand-receptor is crucial for regulating cell behavior. The oligomerization or hetero-aggregation of the membrane receptor driven by the ligand realizes the rearrangement of apoptotic signals, providing a new ideal tool for tumor therapy. However, the construction of a stable model of cytomembrane receptor aggregation and the development of a universal anti-tumor therapy model on the cellular surface remain challenging. This work describes the construction of a "multi-catcher" flexible structure GC-chol-apt-cDNA with a suitable integration of the oligonucleotide aptamer (apt) and cholesterol (chol) on a polymer skeleton glycol chitosan (GC), for the regulation of the nucleolin cluster through strong polyvalent binding and hydrophobic membrane anchoring on the cell surface. This oligonucleotide aptamer shows nearly 100-fold higher affinity than that of the monovalent aptamer and achieves stable anchoring to the plasma membrane for up to 6 h. Moreover, it exerts a high tumor inhibition both in vitro and in vivo by activating endogenous mitochondrial apoptosis pathway through the cluster of nucleolins on the cell membrane. This multi-catcher nano-platform combines the spatial location regulation of cytomembrane receptors with the intracellular apoptotic signaling cascade and represents a promising strategy for antitumor therapy.


Assuntos
Aptâmeros de Nucleotídeos , Neoplasias , Humanos , Polímeros/metabolismo , Ligantes , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Membrana Celular/metabolismo , Receptores de Superfície Celular/metabolismo , Oligonucleotídeos , Linhagem Celular Tumoral , Aptâmeros de Nucleotídeos/farmacologia , Aptâmeros de Nucleotídeos/química , Nucleolina
20.
J Control Release ; 359: 116-131, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37263546

RESUMO

Effective extravasation of therapeutic agents into solid tumors still faces huge challenges. Since the doubted effectiveness of enhanced penetration and retention effect, first-generation neutrophil cytopharmaceuticals with encapsulated drugs have been developed to improve the drug accumulation in tumors based on the active chemotaxis and extravasation of neutrophils. Herein, a new generation of neutrophil cytopharmaceuticals with enhanced tumor-specific extravasation is reported to satisfy more complex clinical demands. This neutrophil cytopharmaceutical is obtained by anchoring vascular endothelial growth factor receptor 2 (VEGFR2)-targeting peptide K237 on neutrophil membrane after endocytosis of chemotherapeutics by neutrophils. Leveraging the cytokine-mediated active migration of neutrophils, the specific-recognition of K237 peptide to tumor vascular endothelium expedites the migration and enhances tight adhesion of neutrophils to vascular endothelium, thus improving the extravasation of therapeutic agents to target sites. Moreover, anti-angiogenesis effect from VEGFR2-blocking by K237 peptide achieves a cooperative tumor destruction with cytotoxic effects from released chemotherapeutics. This study demonstrates the great potential of enhanced proactive extravasation of cytopharmaceuticals via a cell-anchoring technology, leading to expedited drug infiltration and boosted therapeutic effects, which can be applied in other cell therapies to improve efficacy.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Fator A de Crescimento do Endotélio Vascular/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Peptídeos/uso terapêutico , Peptídeos/farmacologia , Adesão Celular , Endotélio Vascular
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