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1.
Cell ; 178(6): 1362-1374.e16, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31447178

RESUMO

TRPA1 is a chemosensory ion channel that functions as a sentinel for structurally diverse electrophilic irritants. Channel activation occurs through an unusual mechanism involving covalent modification of cysteine residues clustered within an amino-terminal cytoplasmic domain. Here, we describe a peptidergic scorpion toxin (WaTx) that activates TRPA1 by penetrating the plasma membrane to access the same intracellular site modified by reactive electrophiles. WaTx stabilizes TRPA1 in a biophysically distinct active state characterized by prolonged channel openings and low Ca2+ permeability. Consequently, WaTx elicits acute pain and pain hypersensitivity but fails to trigger efferent release of neuropeptides and neurogenic inflammation typically produced by noxious electrophiles. These findings provide a striking example of convergent evolution whereby chemically disparate animal- and plant-derived irritants target the same key allosteric regulatory site to differentially modulate channel activity. WaTx is a unique pharmacological probe for dissecting TRPA1 function and its contribution to acute and persistent pain.


Assuntos
Venenos de Escorpião/farmacologia , Canal de Cátion TRPA1/metabolismo , Animais , Células HEK293 , Humanos , Camundongos Endogâmicos C57BL , Ratos Sprague-Dawley , Escorpiões/metabolismo
2.
Development ; 150(22)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37840469

RESUMO

Although mechanical and biochemical descriptions of development are each essential, integration of upstream morphogenic cues with downstream tissue mechanics remains understudied during vertebrate morphogenesis. Here, we developed a two-dimensional chemo-mechanical model to investigate how mechanical properties of the endoderm and transport properties of fibroblast growth factor (FGF) regulate avian hindgut morphogenesis in a coordinated manner. Posterior endoderm cells convert a gradient of FGF ligands into a contractile force gradient, leading to a force imbalance that drives collective cell movements that elongate the forming hindgut tube. We formulated a 2D reaction-diffusion-advection model describing the formation of an FGF protein gradient as a result of posterior displacement of cells transcribing unstable Fgf8 mRNA during axis elongation, coupled with translation, diffusion and degradation of FGF protein. The endoderm was modeled as an active viscous fluid that generates contractile stresses in proportion to FGF concentration. With parameter values constrained by experimental data, the model replicates key aspects of hindgut morphogenesis, suggests that graded isotropic contraction is sufficient to generate large anisotropic cell movements, and provides new insight into how chemo-mechanical coupling across the mesoderm and endoderm coordinates hindgut elongation with axis elongation.


Assuntos
Sistema Digestório , Endoderma , Animais , Endoderma/metabolismo , Sistema Digestório/metabolismo , Morfogênese/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Vertebrados/metabolismo , Mesoderma/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(34): e2306950120, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37590412

RESUMO

Hybrid voltage indicators (HVIs) are chemogenetic sensors that combines the superior photophysical properties of organic dyes and the genetic targetability of protein sensors to report transient membrane voltage changes. They exhibit boosted sensitivity in excitable cells such as neurons and cardiomyocytes. However, the voltage signals recorded during long-term imaging are severely diminished or distorted due to phototoxicity and photobleaching issues. To capture stable electrophysiological activities over a long time, we employ cyanine dyes conjugated with a cyclooctatetraene (COT) molecule as the fluorescence reporter of HVI. The resulting orange-emitting HVI-COT-Cy3 enables high-fidelity voltage imaging for up to 30 min in cultured primary neurons with a sensitivity of ~ -30% ΔF/F0 per action potential (AP). It also maximally preserves the signal of individual APs in cardiomyocytes. The far-red-emitting HVI-COT-Cy5 allows two-color voltage/calcium imaging with GCaMP6s in neurons and cardiomyocytes for 15 min. We leverage the HVI-COT series with reduced phototoxicity and photobleaching to evaluate the impact of drug candidates on the electrophysiology of excitable cells.


Assuntos
Dermatite Fototóxica , Miócitos Cardíacos , Humanos , Neurônios , Diagnóstico por Imagem , Corantes
4.
Cancer Metastasis Rev ; 43(1): 87-113, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37789138

RESUMO

Cancer cell plasticity plays a crucial role in tumor initiation, progression, and metastasis and is implicated in the multiple cancer defense mechanisms associated with therapy resistance and therapy evasion. Cancer resistance represents one of the significant obstacles in the clinical management of cancer. Some reversal chemosensitizing agents have been developed to resolve this serious clinical problem, but they have not yet been proven applicable in oncological practice. Activated nuclear factor kappa B (NF-κB) is a frequently observed biomarker in chemoresistant breast cancer (BC). Therefore, it denotes an attractive cellular target to mitigate cancer resistance. We summarize that flavonoids represent an essential class of phytochemicals that act as significant regulators of NF-κB signaling and negatively affect the fundamental cellular processes contributing to acquired cell plasticity and drug resistance. In this regard, flavokawain A, icariin, alpinetin, genistein, wogonin, apigenin, oroxylin A, xanthohumol, EGCG, hesperidin, naringenin, orientin, luteolin, delphinidin, fisetin, norwogonin, curcumin, cardamonin, methyl gallate and catechin-3-O-gallate, ampelopsin, puerarin, hyperoside, baicalein, paratocarpin E, and kaempferol and also synthetic flavonoids such as LFG-500 and 5,3'-dihydroxy-3,6,7,8,4'-pentamethoxyflavone have been reported to specifically interfere with the NF-κB pathway with complex signaling consequences in BC cells and could be potentially crucial in re-sensitizing unresponsive BC cases. The targeting NF-κB by above-mentioned flavonoids includes the modification of tumor microenvironment and epithelial-mesenchymal transition, growth factor receptor regulations, and modulations of specific pathways such as PI3K/AKT, MAP kinase/ERK, and Janus kinase/signal transduction in BC cells. Besides that, NF-κB signaling in BC cells modulated by flavonoids has also involved the regulation of ATP-binding cassette transporters, apoptosis, autophagy, cell cycle, and changes in the activity of cancer stem cells, oncogenes, or controlling of gene repair. The evaluation of conventional therapies in combination with plasticity-regulating/sensitizing agents offers new opportunities to make significant progress towards a complete cure for cancer.


Assuntos
Neoplasias da Mama , NF-kappa B , Humanos , Feminino , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Plasticidade Celular , Transdução de Sinais , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Microambiente Tumoral
5.
Proc Natl Acad Sci U S A ; 119(29): e2203994119, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858319

RESUMO

The development of more effective tumor therapy remains challenging and has received widespread attention. In the past decade, there has been growing interest in synergistic tumor therapy based on supramolecular coordination complexes. Herein, we describe two triangular metallacycles (1 and 2) constructed by the formation of pyridyl boron dipyrromethene (BODIPY)-platinum coordination. Metallacycle 2 had considerable tumor penetration, as evidenced by the phenylthiol-BODIPY ligand imparting red fluorescent emission at ∼660 nm, enabling bioimaging, and transport visualization within the tumor. Based on the therapeutic efficacy of the platinum(II) acceptor and high singlet oxygen (1O2) generation ability of BODIPY, 2 was successfully incorporated into nanoparticles and applied in chemo-photodynamic tumor therapy against malignant human glioma U87 cells, showing excellent synergistic therapeutic efficacy. A half-maximal inhibitory concentration of 0.35 µM was measured for 2 against U87 cancer cells in vitro. In vivo experiments indicated that 2 displayed precise tumor targeting ability and good biocompatibility, along with strong antitumor effects. This work provides a promising approach for treating solid tumors by synergistic chemo-photodynamic therapy of supramolecular coordination complexes.


Assuntos
Compostos de Boro , Neoplasias , Fotoquimioterapia , Compostos de Boro/uso terapêutico , Linhagem Celular Tumoral , Complexos de Coordenação/uso terapêutico , Sinergismo Farmacológico , Humanos , Neoplasias/tratamento farmacológico , Platina/uso terapêutico , Porfobilinogênio/análogos & derivados
6.
Nano Lett ; 24(6): 1843-1850, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38316029

RESUMO

The penetrating growth of Li into the inorganic solid-state electrolyte (SSE) is one key factor limiting its practical application. Research to understand the underlying mechanism of Li penetration has been ongoing for years and is continuing. Here, we report an in situ scanning electron microscopy methodology to investigate the dynamic behaviors of isolated Li filaments in the garnet SSE under practical cycling conditions. We find that the filaments tend to grow in the SSE, while surprisingly, those filaments can self-dissolve with a decrease in the current density without a reversal of the current direction. We further build a coupled electro-chemo-mechanical model to assess the interplay between electrochemistry and mechanics during the dynamic evolution of filaments. We reveal that filament growth is strongly regulated by the competition between the electrochemical driving force and mechanical resistive force. The numerical results provide rational guidance for the design of solid-state batteries with excellent properties.

7.
Nano Lett ; 24(5): 1544-1552, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38270095

RESUMO

Lithium-metal (Li0) anodes potentially enable all-solid-state batteries with high energy density. However, it shows incompatibility with sulfide solid-state electrolytes (SEs). One strategy is introducing an interlayer, generally made of a mixed ionic-electronic conductor (MIEC). Yet, how Li behaves within MIEC remains unknown. Herein, we investigated the Li dynamics in a graphite interlayer, a typical MIEC, by using operando neutron imaging and Raman spectroscopy. This study revealed that intercalation-extrusion-dominated mechanochemical reactions during cell assembly transform the graphite into a Li-graphite interlayer consisting of SE, Li0, and graphite-intercalation compounds. During charging, Li+ preferentially deposited at the Li-graphite|SE interface. Upon further plating, Li0-dendrites formed, inducing short circuits and the reverse migration of Li0. Modeling indicates the interface has the lowest nucleation barrier, governing lithium transport paths. Our study elucidates intricate mechano-chemo-electrochemical processes in mixed conducting interlayers. The behavior of Li+ and Li0 in the interlayer is governed by multiple competing factors.

8.
Glycobiology ; 34(5)2024 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-38401165

RESUMO

Glycosaminoglycans are extended linear polysaccharides present on cell surfaces and within the extracellular matrix that play crucial roles in various biological processes. Two prominent glycosaminoglycans, heparan sulfate and chondroitin sulfate, are covalently linked to proteoglycan core proteins through a common tetrasaccharide linker comprising glucuronic acid, galactose, galactose, and xylose moities. This tetrasaccharide linker is meticulously assembled step by step by four Golgi-localized glycosyltransferases. The addition of the fifth sugar moiety, either N-acetylglucosamine or N-acetylgalactosamine, initiates further chain elongation, resulting in the formation of heparan sulfate or chondroitin sulfate, respectively. Despite the fundamental significance of this step in glycosaminoglycan biosynthesis, its regulatory mechanisms have remained elusive. In this study, we detail the expression and purification of the four linker-synthesizing glycosyltransferases and their utilization in the production of fluorescent peptides carrying the native tetrasaccharide linker. We generated five tetrasaccharide peptides, mimicking the core proteins of either heparan sulfate or chondroitin sulfate proteoglycans. These peptides were readily accepted as substrates by the EXTL3 enzyme, which adds an N-acetylglucosamine moiety, thereby initiating heparan sulfate biosynthesis. Importantly, EXTL3 showed a preference towards peptides mimicking the core proteins of heparan sulfate proteoglycans over the ones from chondroitin sulfate proteoglycans. This suggests that EXTL3 could play a role in the decision-making step during glycosaminoglycan biosynthesis. The innovative strategy for chemo-enzymatic synthesis of fluorescent-labeled linker-peptides promises to be instrumental in advancing future investigations into the initial steps and the divergent step of glycosaminoglycan biosynthesis.


Assuntos
Acetilglucosamina , Sulfatos de Condroitina , Galactose , Glicosaminoglicanos/metabolismo , Heparitina Sulfato/metabolismo , Proteoglicanas de Sulfatos de Condroitina , Oligossacarídeos , Peptídeos , Glicosiltransferases
9.
Curr Issues Mol Biol ; 46(4): 3394-3407, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38666943

RESUMO

Nowadays, the explosion of knowledge in the field of epigenetics has revealed new pathways toward the treatment of multifactorial diseases, rendering the key players of the epigenetic machinery the focus of today's pharmaceutical landscape. Among epigenetic enzymes, DNA methyltransferases (DNMTs) are first studied as inhibition targets for cancer treatment. The increasing clinical interest in DNMTs has led to advanced experimental and computational strategies in the search for novel DNMT inhibitors. Considering the importance of epigenetic targets as a novel and promising pharmaceutical trend, the present study attempted to discover novel inhibitors of natural origin against DNMTs using a combination of structure and ligand-based computational approaches. Particularly, a pharmacophore-based virtual screening was performed, followed by molecular docking and molecular dynamics simulations in order to establish an accurate and robust selection methodology. Our screening protocol prioritized five natural-derived compounds, derivatives of coumarins, flavones, chalcones, benzoic acids, and phenazine, bearing completely diverse chemical scaffolds from FDA-approved "Epi-drugs". Their total DNMT inhibitory activity was evaluated, revealing promising results for the derived hits with an inhibitory activity ranging within 30-45% at 100 µM of the tested compounds.

10.
Biochem Biophys Res Commun ; 735: 150828, 2024 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-39418772

RESUMO

Previous studies have demonstrated that combination therapy involving radiotherapy and aspirin decreases the survival rate of cancer cells. However, the mechanism by which aspirin exerts its radiation sensitization effect at the in vivo level remains largely unclear. In this study, we employed Caenorhabditis elegans (C. elegans) as a model organism to investigate the effect of aspirin combined with radio/chemo-therapy on tumors at the individual level. Here, we illustrate that high-dose aspirin increases the expression of genes involved in core apoptosis pathways (egl-1, ced-9, ced-4 and ced-3) and induces germ cell apoptosis in C. elegans through mitochondrial outer membrane permeabilization (MOMP) and elevation of reactive oxygen species (ROS) levels. Crucially, aspirin-induces ROS upregulates the expression of genes critical for DNA damage response (hus-1, clk-2 and cep-1) and genes involved in MAPK pathways (lin-45, mek-2, mpk-1, sek-1 and pmk-1), thereby mediating the enhanced sensitivity of radio/chemo-therapy by aspirin. Notably, aspirin fails to induce germ cell apoptosis and enhance radio/chemo-therapy in C. elegans lacking the expression of each of those genes. Furthermore, in a C. elegans tumor-like symptom model, aspirin enhances radio/chemo-therapy sensitivity through ROS induction. However, low-dose aspirin can diminish the apoptotic signal of reproductive cells in C. elegans and exert anti-inflammatory effects. Our research results suggest that the tumor-suppressive and radio/chemo-therapy sensitizing effects of aspirin provide robust experimental evidence for improving the clinical efficacy of tumor radio/chemo-therapy and deepening our understanding of aspirin's mechanism of action in cancer.

11.
Small ; 20(30): e2308562, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38441369

RESUMO

Diagnosis and treatment of tumor especially drug-resistant tumor remains a huge challenge, which requires intelligent nanomedicines with low toxic side effects and high efficacy. Herein, deformable smart DNA nanomachines are developed for synergistic intracellular cancer-related miRNAs imaging and chemo-gene therapy of drug-resistant tumors. The tetrahedral DNA framework (MA-TDNA) with fluorescence quenched component and five antennas is self-assembled first, and then DOX molecules are loaded on the MA-TDNAs followed by linking MUC1-aptamer and Mcl-1 siRNA to the antennas of MA-TDNA, so that the apt-MA-TDNA@DOX-siRNA (DNA nanomachines) is constructed. The DNA nanomachine can respond to two tumor-related miRNAs in vitro and in vivo, which can undergo intelligent miRNA-triggered opening of the framework, resulting in the "turn on" of the fluorescence for sensitively and specifically sensing intracellular miRNAs. Meanwhile, both miRNA-responded rapid release and pH-responded release of DOX are achieved for chemotherapy of tumor. In addition, the gene therapy of the DNA nanomachines is achieved due to the miRNA-specific capture and the RNase H triggered release of Mcl-1 siRNA. The DNA nanomachines intergrading both tumor imaging and chemo-gene therapy in single nanostructures realized efficient tumor-targeted, image-guided, and microenvironment-responsive tumor diagnosis and treatment, which provides a synergetic antitumor effect on drug-resistant tumor.


Assuntos
DNA , Doxorrubicina , Resistencia a Medicamentos Antineoplásicos , Terapia Genética , MicroRNAs , MicroRNAs/genética , Humanos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Doxorrubicina/farmacologia , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Terapia Genética/métodos , DNA/química , Animais , Neoplasias/terapia , Neoplasias/diagnóstico por imagem , Neoplasias/genética , RNA Interferente Pequeno , Linhagem Celular Tumoral , Espaço Intracelular/metabolismo
12.
Small ; 20(26): e2309850, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38225710

RESUMO

Although chemotherapy has the potential to induce tumor immunotherapy via immunogenic cell death (ICD) effects, how to control the intensity of the immune responses still deserves further exploration. Herein, a controllable ultrasound (US)-triggered chemo-immunotherapy nanoagonist is successfully synthesized by utilizing the pH and reactive oxygen species (ROS) dual-responsive PEG-polyphenol to assemble sonosensitizer zinc oxide (ZnO) and doxorubicin (DOX). The PZnO@DOX nanoparticles have an intelligent disassembly to release DOX and zinc ions in acidic pH conditions. Notably, US irradiation generates ROS by sonodynamic therapy and accelerates the drug release process. Interestingly, after the PZnO@DOX+US treatment, the injured cells release double-stranded DNA (dsDNA) from the nucleus and mitochondria into the cytosol. Subsequently, both the dsDNA and zinc ions bind with cyclic GMP-AMP synthase and activate the stimulator of interferon genes (STING) pathway, resulting in the dendritic cell maturation, ultimately promoting DOX-induced ICD effects and antigen-specific T cell immunity. Therefore, chemotherapy-induced immune responses can be modulated by non-invasive control of US.


Assuntos
Doxorrubicina , Morte Celular Imunogênica , Nanopartículas , Óxido de Zinco , Doxorrubicina/farmacologia , Doxorrubicina/química , Morte Celular Imunogênica/efeitos dos fármacos , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Animais , Nanopartículas/química , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Membrana/metabolismo , Humanos , Ondas Ultrassônicas , Camundongos , Concentração de Íons de Hidrogênio , Liberação Controlada de Fármacos , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , DNA/química , DNA/metabolismo
13.
Chembiochem ; 25(2): e202300627, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-37947295

RESUMO

Antibiotics are micropollutants accumulating in our rivers and wastewaters, potentially leading to bacterial antibiotic resistance, a worldwide problem to which there is no current solution. Here, we have developed an environmentally friendly two-step process to transform the antibiotic rifampicin (RIF) into non-antimicrobial compounds. The process involves an enzymatic oxidation step by the bacterial CotA-laccase and a hydrogen peroxide bleaching step. NMR identified rifampicin quinone as the main product of the enzymatic oxidation. Growth of Escherichia coli strains in the presence of final degradation products (FP) and minimum inhibitory concentration (MIC) measurements confirmed that FP are non-anti-microbial compounds, and bioassays suggest that FP is not toxic to eukaryotic organisms. Moreover, competitive fitness assays between susceptible and RIF-resistant bacteria show that susceptible bacteria is strongly favoured in the presence of FP. Our results show that we have developed a robust and environmentally friendly process to effectively remediate rifampicin from antibiotic contaminated environments.


Assuntos
Peróxido de Hidrogênio , Lacase , Lacase/química , Peróxido de Hidrogênio/metabolismo , Rifampina/farmacologia , Rifampina/metabolismo , Escherichia coli/metabolismo , Antibacterianos/farmacologia , Antibacterianos/metabolismo
14.
Chembiochem ; 25(6): e202300839, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38265820

RESUMO

Switching from oil-based to bio-based feedstocks to ensure the green transition to a sustainable and circular future is one of the most pressing challenges faced by many industries worldwide. For the cosmetics and personal and house care industries there is a strong drive to accelerate this transition from the customers that starts favoring the purchase of naturally derived and bio-degradable products over the traditionally available products. In this work we developed a series of fully biobased macromolecules constituted of a glycerol-based oligoester backbone. Based on the subsequent derivatization with fatty acids or peptides, the resulting products may find application as emulsifiers, wetting agents, and potential vectors for the delivery of bioactive peptides. All steps of the resulting macromolecules were conducted following the green chemistry principles with no toxic or environmentally damaging compounds that were used in the overall production process.


Assuntos
Glicerol , Polímeros , Glicerol/química , Polímeros/química , Peptídeos , Ácidos Graxos/química
15.
Mol Carcinog ; 63(4): 742-756, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38270247

RESUMO

Nuclear factor erythroid 2-related factor 2 (Nrf2) significantly contributes to drug resistance of cancer cells, and Nrf2 inhibitors have been vigorously pursued. Repurposing of existing drugs, especially anticancer drugs, is a straightforward and promising strategy to find clinically available Nrf2 inhibitors and effective drug combinations. Topoisomerase inhibitors SN-38 (an active metabolite of irinotecan), topotecan, mitoxantrone, and epirubicin were found to significantly suppress Nrf2 transcriptional activity in cancer cells. SN-38, the most potent one among them, significantly inhibited the transcription of Nrf2, as indicated by decreased mRNA level and binding of RNA polymerase II to NFE2L2 gene, while no impact on Nrf2 protein or mRNA degradation was observed. SN-38 synergized with Nrf2-sensitive anticancer drugs such as mitomycin C in killing colorectal cancer cells, and irinotecan and mitomycin C synergistically inhibited the growth of SW480 xenografts in nude mice. Our study identified SN-38 and three other topoisomerase inhibitors as Nrf2 inhibitors, revealed the Nrf2-inhibitory mechanism of SN-38, and indicate that clinically feasible drug combinations could be designed based on their interactions with Nrf2 signaling.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Animais , Camundongos , Humanos , Irinotecano/farmacologia , Camptotecina/farmacologia , Mitomicina/farmacologia , Camundongos Nus , Fator 2 Relacionado a NF-E2/genética , Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Inibidores da Topoisomerase/farmacologia , Combinação de Medicamentos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética
16.
Artigo em Inglês | MEDLINE | ID: mdl-39453485

RESUMO

INTRODUCTION AND AIM: Radioligand therapy (RLT) with 177Lu-labelled prostate specific membrane antigen ([177Lu]Lu-PSMA-X, referring with "PSMA-X" to a generic PSMA chemical compound) inhibitors has emerged as a viable treatment option in metastatic castration resistant prostate cancer patients having previously progressed on taxane and androgen receptor inhibitors. The aim of this study was to perform a systematic review and meta-analysis to assess the therapeutic efficacy of [177Lu]Lu-PSMA-X compared to taxane chemotherapy in taxane-chemo-naïve patients with metastatic castration-resistant prostate cancer. MATERIALS AND METHODS: Searches in several bibliographic databases were made using relevant key words, and articles published up to March 2024 were included. The endpoints included prostate specific antigen (PSA) response rate (RR), progression-free survival, and overall survival. Individual patient data were pooled when feasible. PSA50 was defined as the median proportion of patients achieving at least a 50% decline in serum PSA from baseline. A meta-analysis of the PSA50 response rate (proportion meta-analysis) was performed, generating pooled estimates and 95% confidence intervals (95% CI). RESULTS: From the initially selected 8,414 studies published between 2019 and 2023, 24 were included in the [177Lu]Lu-PSMA-X treated group and 17 in the taxane treated group. Our findings show that [177Lu]Lu-PSMA-X RLT yielded comparable PSA50 responses in taxane-naïve patients versus those receiving taxane chemotherapy, despite considerable study heterogeneity. Notably, the taxane-naïve group had more extensive pretreatment. CONCLUSIONS: This meta-analysis combines the largest cohorts of taxane-naïve mCRPC patients treated with [177Lu]Lu-PSMA-X RLT and taxane-treated mCRPC. It underscores similar PSA50 response rates in both groups, suggesting a potential role for [177Lu]Lu-PSMA-X RLT in taxane-naïve patients who cannot or choose not to undergo chemotherapy.

17.
BMC Cancer ; 24(1): 1213, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39350056

RESUMO

BACKGROUND: The main challenge in treating ovarian cancer is chemotherapy resistance. Previous studies have shown that PAK2 is highly expressed in various cancers. This research investigates whether increased PAK2 expression contributes to chemo-resistance and poor prognosis in ovarian cancer. METHODS: Initially, bioinformatics analysis was used to assess the importance of PAK2 mRNA up-regulation in ovarian cancer. This was then validated using tissue microarray to confirm PAK2 protein expression and localization in clinical samples. Univariate and multivariate logistic regression analyses were carried out to identify potential risk factors for chemo-resistance in serous epithelial ovarian cancer (EOC), while multivariate Cox regression and Kaplan-Meier analysis were conducted to ascertain prognostic factors for overall survival (OS) and disease-free survival (DFS) in patients with serous EOC. In vitro experiments were conducted to verify if inhibiting PAK2 expression could increase A2780/Taxol cells' sensitivity to paclitaxel, as shown by evaluating cell proliferation, apoptosis, transwell, and clone formation. Additionally, the interaction between PAK2, lnc-SNHG1, and miR-216b-5p was verified using RIP and luciferase reporter assays. Rescue experiments were undertaken to examine the influence of the lnc-SNHG1/miR-216b-5p/PAK2 axis on the development of paclitaxel resistance in A2780/Taxol cells. RESULTS: The bioinformatics analysis indicated a notable increase in PAK2 expression in ovarian malignant tumors compared to adjacent tissues, particularly in patients with stage III-IV disease compared to those with stage I-II disease (P = 0.0056). Elevated levels of PAK2 were linked to reduced OS in ovarian cancer patients, although no significant association was observed with DFS. Immunohistochemistry findings further supported these results, showing positive PAK2 protein expression in chemo-resistant serous EOC tissues, predominantly localized in the cytoplasm, which correlated with poorer OS and DFS outcomes. In vitro experiments demonstrated that the downregulation of PAK2 in A2780/Taxol cells led to a reduction in colony formation, an increase in apoptosis, and a diminished capacity for cell invasion. Subsequent analysis confirmed that lnc-SNHG1 functions as a competitive endogenous RNA (ceRNA) by interacting with miR-216b-5p and regulating PAK2 expression. Rescue experiments demonstrated that lnc-SNHG1 induces resistance to paclitaxel in A2780/Taxol cells by modulating the miR-216b-5p/PAK2 axis. CONCLUSIONS: PAK2 shows promise as a predictor of chemotherapy resistance and poor outcomes in ovarian cancer, indicating its potential use as a treatment target to overcome this resistance.


Assuntos
Carcinoma Epitelial do Ovário , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , MicroRNAs , Neoplasias Ovarianas , Paclitaxel , Quinases Ativadas por p21 , Humanos , Quinases Ativadas por p21/metabolismo , Quinases Ativadas por p21/genética , Feminino , Resistencia a Medicamentos Antineoplásicos/genética , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/mortalidade , Prognóstico , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/metabolismo , Carcinoma Epitelial do Ovário/patologia , Carcinoma Epitelial do Ovário/mortalidade , MicroRNAs/genética , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Pessoa de Meia-Idade , Proliferação de Células , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Apoptose/efeitos dos fármacos , Regulação para Cima
18.
BMC Cancer ; 24(1): 459, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609887

RESUMO

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) represents a common and heterogeneous malignancy of the oral cavity, pharynx and larynx. Surgery and radio(chemo)therapy are the standard treatment options and also have great influence on the composition of the tumor microenvironment and immune cell functions. However, the impact of radio(chemo)therapy on the distribution and characteristics of circulating monocyte subsets in HNSCC are not fully understood. METHODS: Expression patterns of adhesion molecules and chemokine receptors CD11a (integrin-α L; LFA-1), CD11b (integrin-α M; Mac-1), CD11c (integrin-α X), CX3CR1 (CX3CL1 receptor) and checkpoint molecule PD-L1 (programmed cell death ligand-1) were investigated upon radio(chemo)therapeutic treatment using flow cytometry. Furthermore, comprehensive analysis of plasma cytokines was performed before and after treatment using ELISA measurements. RESULTS: Our data reveal a partial recovery of circulating monocytes in HNSCC patients upon radio(chemo)therapeutic treatment, with differential effects of the individual therapy regimen. PD-L1 expression on non-classical monocytes significantly correlates with the individual plasma levels of chemokine CXCL11 (C-X-C motif chemokine 11). CONCLUSIONS: Further comprehensive investigations on larger patient cohorts are required to elucidate the meaningfulness of peripheral blood monocyte subsets and chemokine CXCL11 as potential bioliquid indicators in HNSCC with regard to therapy response and the individual immunological situation.


Assuntos
Neoplasias de Cabeça e Pescoço , Monócitos , Humanos , Antígeno B7-H1 , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Quimiocina CXCL11 , Neoplasias de Cabeça e Pescoço/terapia , Microambiente Tumoral
19.
BMC Cancer ; 24(1): 403, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561708

RESUMO

BACKGROUND: During the last decade, twelve studies have been published investigating physical exercise interventions (PEIs) in patients with head and neck cancer (HNC) during radiotherapy (RT), chemoradiation (CRT) or bioradiation (BRT). These studies showed that these PEIs are safe and feasible. However, only two of these studies were randomised clinical trials (RCTs) with a satisfying sample size. Thereby, there is no cost-effectiveness study related to a PEI during RT, CRT or BRT ((C/B)RT) for patients with HNC. Therefore, the aim of this study is to investigate and compare physical performance, muscle strength, fatigue, quality of life (QoL), body mass index (BMI), nutritional status, physical activity, treatment tolerability, and health care related costs in patients with HNC with and without a 10 week PEI during (C/B)RT. METHODS: This study, based on a trial within cohorts (TwiCs) design, will contain a prospective cohort of at least 112 patients. Fifty-six patients will randomly be invited for an experimental 10 week PEI. This PEI consists of both resistance and endurance exercises to optimize physical performance, muscle strength, fatigue, QoL, BMI, nutritional status, physical activity, and treatment tolerability of (C/B)RT. Measurements are at baseline, after 12 weeks, 6 months, and at 12 months. Statistical analyses will be performed for intention-to-treat and instrumental variable analysis. DISCUSSION: This study seeks to investigate physical, QoL, and economic implications of a PEI. With a substantial sample size, this study attempts to strengthen and expand knowledge in HNC care upon PEI during (C/B)RT. In conclusion, this study is dedicated to provide additional evidence for PEI in patients with HNC during (C/B)RT. TRIAL REGISTRATION: protocol was registered at clinicaltrials.gov with number NCT05988060 on 3 August 2023.


Assuntos
Exercício Físico , Neoplasias de Cabeça e Pescoço , Humanos , Fadiga , Neoplasias de Cabeça e Pescoço/radioterapia , Desempenho Físico Funcional , Qualidade de Vida , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
Anal Biochem ; 685: 115404, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-37993043

RESUMO

In the category of 2D materials, MoS2 a transition metal dichalcogenide, is a novel and intriguing class of materials with interesting physicochemical properties, explored in applications ranging from cutting-edge optoelectronic to the frontiers of biomedical and biotechnology. MoS2 nanostructures an alternative to heavy toxic metals exhibit biocompatibility, low toxicity and high stability, and high binding affinity to biomolecules. MoS2 nanostructures provide a lot of opportunities for the advancement of novel biosensing, nanodrug delivery system, electrochemical detection, bioimaging, and photothermal therapy. Much efforts have been made in recent years to improve their physiochemical properties by developing a better synthesis approach, surface functionalization, and biocompatibility for their safe use in the advancement of biomedical applications. The understanding of parameters involved during the development of nanostructures for their safe utilization in biomedical applications has been discussed. Computational studies are included in this article to understand better the properties of MoS2 and the mechanism involved in their interaction with biomolecules. As a result, we anticipate that this combined experimental and computational studies of MoS2 will inspire the development of nanostructures with smart drug delivery systems, and add value to the understanding of two-dimensional smart nano-carriers.


Assuntos
Nanoestruturas , Elementos de Transição , Molibdênio/química , Nanoestruturas/química , Sistemas de Liberação de Medicamentos
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