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Spatial, momentum and energy separation of electronic spins in condensed-matter systems guides the development of new devices in which spin-polarized current is generated and manipulated1-3. Recent attention on a set of previously overlooked symmetry operations in magnetic materials4 leads to the emergence of a new type of spin splitting, enabling giant and momentum-dependent spin polarization of energy bands on selected antiferromagnets5-10. Despite the ever-growing theoretical predictions, the direct spectroscopic proof of such spin splitting is still lacking. Here we provide solid spectroscopic and computational evidence for the existence of such materials. In the noncoplanar antiferromagnet manganese ditelluride (MnTe2), the in-plane components of spin are found to be antisymmetric about the high-symmetry planes of the Brillouin zone, comprising a plaid-like spin texture in the antiferromagnetic (AFM) ground state. Such an unconventional spin pattern, further found to diminish at the high-temperature paramagnetic state, originates from the intrinsic AFM order instead of spin-orbit coupling (SOC). Our finding demonstrates a new type of quadratic spin texture induced by time-reversal breaking, placing AFM spintronics on a firm basis and paving the way for studying exotic quantum phenomena in related materials.
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Cell membranes are incredibly complex environments containing hundreds of components. Despite substantial advances in the past decade, fundamental questions related to lipid-lipid interactions and heterogeneity persist. This review explores the complexity of lipid membranes, showcasing recent advances in vibrational spectroscopy to characterize the structure, dynamics, and interactions at the membrane interface. We include an overview of modern techniques such as surface-enhanced infrared spectroscopy as a steady-state technique with single-bilayer sensitivity, two-dimensional sum-frequency generation spectroscopy, and two-dimensional infrared spectroscopy to measure time-evolving structures and dynamics with femtosecond time resolution. Furthermore, we discuss the potential of multiscale molecular dynamics (MD) simulations, focusing on recently developed simulation algorithms, which have emerged as a powerful approach to interpret complex spectra. We highlight the ongoing challenges in studying heterogeneous environments in multicomponent membranes via current vibrational spectroscopic techniques and MD simulations. Overall, this review provides an up-to-date comprehensive overview of the powerful combination of vibrational spectroscopy and simulations, which has great potential to illuminate lipid-lipid, lipid-protein, and lipid-water interactions in the intricate conformational landscape of cell membranes.
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Membrana Celular , Bicamadas Lipídicas , Simulação de Dinâmica Molecular , Vibração , Membrana Celular/química , Membrana Celular/metabolismo , Bicamadas Lipídicas/química , Lipídeos de Membrana/química , Espectrofotometria Infravermelho/métodos , Água/química , Proteínas de Membrana/químicaRESUMO
Small bowel adenocarcinoma (SBA) is a rare and aggressive malignancy with limited treatment options and poor prognosis. The molecular landscape and immunological characteristics of SBA are poorly understood. Here, we performed comprehensive mutation profiling of tissue and plasma biopsies from 143 and 42 patients with SBA. Analysis showed that SBA had a distinct mutation spectrum from left- and right-sided colorectal carcinoma. Plasma biopsy had high concordance with tissue biopsy for single nucleotide variants and structural variants, but low concordance for copy number variations, which showed that plasma biopsy can be an alternative to tissue biopsy. Moreover, we analyzed the association of TMB with clinical and molecular features, and found that TMB was significantly higher in tumors with DNA damage response alterations. Our findings provide valuable insights into the molecular and immunological features of SBA and demonstrate the potential of plasma biopsy as a non-invasive method for SBA diagnosis and treatment.
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Adenocarcinoma , Variações do Número de Cópias de DNA , Humanos , Intestino Delgado , Adenocarcinoma/genética , Biópsia , Genômica , Mutação , Sequenciamento de Nucleotídeos em Larga Escala/métodosRESUMO
Cell signaling is an important process involving complex interactions between lipids and proteins. The myristoylated alanine-rich C-kinase substrate (MARCKS) has been established as a key signaling regulator, serving a range of biological roles. Its effector domain (ED), which anchors the protein to the plasma membrane, induces domain formation in membranes containing phosphatidylinositol 4,5-bisphosphate (PIP2) and phosphatidylserine (PS). The mechanisms governing the MARCKS-ED binding to membranes remain elusive. Here, we investigate the composition-dependent affinity and MARCKS-ED-binding-induced changes in interfacial environments using two-dimensional infrared spectroscopy and fluorescence anisotropy. Both negatively charged lipids facilitate the MARCKS-ED binding to lipid vesicles. Although the hydrogen-bonding structure at the lipid-water interface remains comparable across vesicles with varied lipid compositions, the dynamics of interfacial water show divergent patterns due to specific interactions between lipids and peptides. Our findings also reveal that PIP2 becomes sequestered by bound peptides, while the distribution of PS exhibits no discernible change upon peptide binding. Interestingly, PIP2 and PS become colocalized into domains both in the presence and absence of MARCKS-ED. More broadly, this work offers molecular insights into the effects of membrane composition on binding.
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Substrato Quinase C Rico em Alanina Miristoilada , Fosfatidilinositol 4,5-Difosfato , Fosfatidilserinas , Ligação Proteica , Fosfatidilinositol 4,5-Difosfato/química , Fosfatidilinositol 4,5-Difosfato/metabolismo , Fosfatidilserinas/química , Fosfatidilserinas/metabolismo , Substrato Quinase C Rico em Alanina Miristoilada/metabolismo , Substrato Quinase C Rico em Alanina Miristoilada/química , Peptídeos/química , Peptídeos/metabolismo , Domínios Proteicos , Água/química , Membrana Celular/metabolismo , Membrana Celular/química , Sequência de AminoácidosRESUMO
The gut microbiota has been demonstrated to be correlated with the clinical phenotypes of diseases, including cancers. However, there are few studies on clinical subtyping based on the gut microbiota, especially in breast cancer (BC) patients. Here, using machine learning methods, we analysed the gut microbiota of BC, colorectal cancer (CRC), and gastric cancer (GC) patients to identify their shared metabolic pathways and the importance of these pathways in cancer development. Based on the gut microbiota-related metabolic pathways, human gene expression profile and patient prognosis, we established a novel BC subtyping system and identified a subtype called "challenging BC". Tumours with this subtype have more genetic mutations and a more complex immune environment than those of other subtypes. A score index was proposed for in-depth analysis and showed a significant negative correlation with patient prognosis. Notably, activation of the TPK1-FOXP3-mediated Hedgehog signalling pathway and TPK1-ITGAE-mediated mTOR signalling pathway was linked to poor prognosis in "challenging BC" patients with high scores, as validated in a patient-derived xenograft (PDX) model. Furthermore, our subtyping system and score index are effective predictors of the response to current neoadjuvant therapy regimens, with the score index significantly negatively correlated with both treatment efficacy and the number of immune cells. Therefore, our findings provide valuable insights into predicting molecular characteristics and treatment responses in "challenging BC" patients.
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Neoplasias da Mama , Microbioma Gastrointestinal , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/microbiologia , Neoplasias da Mama/metabolismo , Feminino , Prognóstico , Animais , Camundongos , Biomarcadores Tumorais , Regulação Neoplásica da Expressão Gênica , Transdução de Sinais , Perfilação da Expressão Gênica , Ensaios Antitumorais Modelo de Xenoenxerto , MultiômicaRESUMO
BACKGROUND: Studies on various thrombopoietic agents for cancer treatment-induced thrombocytopenia (CTIT) in China are lacking. This study aimed to provide detailed clinical profiles to understand the outcomes and safety of different CTIT treatment regimens. METHODS: In this retrospective, cross-sectional study, 1664 questionnaires were collected from 33 hospitals between March 1 and July 1, 2021. Patients aged >18 years were enrolled who were diagnosed with CTIT and treated with recombinant interleukin 11 (rhIL-11), recombinant thrombopoietin (rhTPO), or a thrombopoietin receptor agonist (TPO-RA). The outcomes, compliance, and safety of different treatments were analyzed. RESULTS: Among the 1437 analyzable cases, most patients were treated with either rhTPO alone (49.3%) or rhIL-11 alone (27.0%). The most common combination regimen used was rhTPO and rhIL-11 (10.9%). Platelet transfusions were received by 117 cases (8.1%). In multivariate analysis, rhTPO was associated with a significantly lower proportion of platelet recovery, platelet transfusion, and hospitalization due to chemotherapy-induced thrombocytopenia (CIT) than rhIL-11 alone. No significant difference was observed in the time taken to achieve a platelet count of >100 × 109/L and chemotherapy dose reduction due to CIT among the different thrombopoietic agents. The outcomes of thrombocytopenia in 170 patients who received targeted therapy and/or immunotherapy are also summarized. The results show that the proportion of platelet recovery was similar among the different thrombopoietic agents. No new safety signals related to thrombopoietic agents were observed in this study. A higher proportion of physicians preferred to continue treatment with TPO-RA alone than with rhTPO and rhIL-11. CONCLUSIONS: This survey provides an overview of CTIT and the application of various thrombopoietic agents throughout China. Comparison of monotherapy with rhIL-11, rhTPO, and TPO-RA requires further randomized clinical trials. The appropriate application for thrombopoietic agents should depend on the pretreatment of platelets, treatment variables, and risk of bleeding. PLAIN LANGUAGE SUMMARY: To provide an overview of the outcome of cancer treatment-induced thrombocytopenia in China, our cross-sectional study analyzed 1437 cases treated with different thrombopoietic agents. Most of the patients were treated with recombinant interleukin 11 (rhIL-11) and recombinant thrombopoietin (rhTPO). rhTPO was associated with a significantly lower proportion of platelet recovery and platelet transfusion compared with rhIL-11.
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Neoplasias , Trombocitopenia , Humanos , China , Estudos Transversais , Interleucina-11/uso terapêutico , Neoplasias/tratamento farmacológico , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Trombocitopenia/induzido quimicamente , Trombocitopenia/tratamento farmacológico , Trombopoetina/uso terapêutico , Adulto Jovem , AdultoRESUMO
BACKGROUND: Chemotherapy remains the standard first-line treatment for pancreatic adenocarcinoma, but with limited efficacy. We aimed to explore the feasibility of adding the PARP inhibitor fuzuloparib to mFOLFIRINOX in the locally advanced/metastatic (LA/M) setting. METHODS: This was the dose-escalation and -expansion, phase 1b portion of a phase 1b/2 study. Patients were given oral fuzuloparib at escalating doses starting at 30 mg twice daily (BID) plus intravenous mFOLFIRINOX q2w for 8-12 cycles, followed by maintenance fuzuloparib at 150 mg BID. Cohorts at the maximal tolerated dose (MTD) and lower dose of fuzuloparib were expanded. Primary endpoints were dose-limiting toxicity (DLT), MTD, and recommended phase 2 dose (RP2D). RESULTS: As of data cutoff on Jan 15, 2023, 39 patients were recruited. 12 patients were enrolled during dose escalation (30 mg [n = 4]; 60 mg [n = 6]; 100 mg [n = 2]). DLT occurred in 1 patient in 60 mg cohort and 1 patient in 100 mg cohort. 60 mg BID was determined to be the MTD, and then 60 and 30 mg cohorts were expanded to 22 and 15 patients, respectively. The most common grade ≥ 3 treatment-related adverse events were hematologic toxicities. Efficacy in 60 mg cohort seemed to be most favorable, with an objective response rate of 50.0% (95% CI, 26.0-74.0) and disease control rate of 94.4% (95% CI, 72.7-99.9). CONCLUSIONS: First-line fuzuloparib plus mFOLFIRINOX followed by maintenance fuzuloparib was generally safe and showed encouraging anti-tumor activity in patients with LA/M pancreatic adenocarcinoma. The RP2D of fuzuloparib combination was 60 mg BID. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04228601.
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Adenocarcinoma , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Pessoa de Meia-Idade , Masculino , Feminino , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Idoso , Adenocarcinoma/tratamento farmacológico , Adulto , Oxaliplatina/administração & dosagem , Oxaliplatina/uso terapêutico , Fluoruracila/administração & dosagem , Fluoruracila/uso terapêutico , Irinotecano/uso terapêutico , Irinotecano/administração & dosagem , Leucovorina/uso terapêutico , Leucovorina/administração & dosagem , Dose Máxima Tolerável , Resultado do TratamentoRESUMO
BACKGROUND: Gastric cancer is one of the most common tumors worldwide, and most patients are deprived of treatment options when diagnosed at advanced stages. PRDM14 has carcinogenic potential in breast and non-small cell lung cancer. however, its role in gastric cancer has not been elucidated. METHODS: We aimed to elucidate the expression of PRDM14 using pan-cancer analysis. We monitored the expression of PRDM14 in cells and patients using quantitative polymerase chain reaction, western blotting, and immunohistochemistry. We observed that cell phenotypes and regulatory genes were influenced by PRDM14 by silencing PRDM14. We evaluated and validated the value of the PRDM14-derived prognostic model. Finally, we predicted the relationship between PRDM14 and small-molecule drug responses using the Connectivity Map and The Genomics of Drug Sensitivity in Cancer databases. RESULTS: PRDM14 was significantly overexpressed in gastric cancer, which identified in cell lines and patients' tissues. Silencing the expression of PRDM14 resulted in apoptosis promotion, cell cycle arrest, and inhibition of the growth and migration of GC cells. Functional analysis revealed that PRDM14 acts in epigenetic regulation and modulates multiple DNA methyltransferases or transcription factors. The PRDM14-derived differentially expressed gene prognostic model was validated to reliably predict the patient prognosis. Nomograms (age, sex, and PRDM14-risk score) were used to quantify the probability of survival. PRDM14 was positively correlated with sensitivity to small-molecule drugs such as TPCA-1, PF-56,227, mirin, and linsitinib. CONCLUSIONS: Collectively, our findings suggest that PRDM14 is a positive regulator of gastric cancer progression. Therefore, it may be a potential therapeutic target for gastric cancer.
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Proteínas de Ligação a DNA , Regulação Neoplásica da Expressão Gênica , Neoplasias Gástricas , Fatores de Transcrição , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Prognóstico , Linhagem Celular Tumoral , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Feminino , Masculino , Nomogramas , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Epigênese GenéticaRESUMO
OBJECTIVE: To evaluate the efficacy and safety of regorafenib monotherapy or in combination with immune-checkpoint inhibitor while treating Chinese patients with metastatic colorectal cancer (mCRC): a real-world study. METHODS: The data of patients with metastatic colorectal cancer who received regorafenib-containing regimen as the third or later line treatment at ten Chinese hospitals from Aug 2017 to Jun 2020 were retrospectively analyzed, including dosing details, survival data as well as adverse events. Survival analysis was further performed for patients administrated with regorafenib monotherapy and combined with an immune-checkpoint inhibitor based on Kaplan-Meier and Cox regression methods. The primary endpoint was overall survival. RESULTS: A total of 537 patients were included with a median age of 61, among whom 376 received regorafenib monotherapy and 245 received regorafenib combined with immune-checkpoint inhibitors. The clinicopathological characteristics of the two groups at baseline were mainly balanced. No significant difference in progression-free survival (PFS) was observed in patients receiving regorafenib monotherapy or combination therapy (3.8 vs. 5.5 months, p = 0.170). In contrast, patients receiving combination therapy had a more prolonged overall survival (OS) than those receiving regorafenib monotherapy (13.5 vs. 10.0 months, p = 0.001). The treatment regimen and regorafenib dosage were significant prognostic factors in the multivariate analysis. Significant benefits in PFS and OS were achieved in KRAS mutant and anti-angiogenesis treatment-naïve subgroups receiving combination therapy compared to monotherapy. No apparent increase was recorded in treatment-related adverse events in patients receiving combination therapy. CONCLUSION: Regorafenib plus an immune-checkpoint inhibitor has already been a widely adopted strategy in the later-line treatment for mCRC in the real world. The combination therapy yielded a significantly prolonged overall survival than regorafenib alone, with a manageable safety profile in Chinese patients, and warrants further investigation. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04835324. Registered 6th April 2021.
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Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Humanos , Estudos Retrospectivos , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Piridinas/efeitos adversos , Compostos de Fenilureia/efeitos adversosRESUMO
α-Conotoxin ImI is a selective antagonist of alpha7 nicotinic acetylcholine receptor (α7 nAChR) that is involved in cancer development. Human alpha fetoprotein domain 3 (AFP3) is a prototype of anticancer agents. In an effort to design drugs for anticancer treatments, we fused the ImI peptide to AFP3 as a fusion protein for testing. The fusion protein (ImI-AFP3) was highly expressed in the insect Bac-to-Bac system. The purified fusion protein was found to have improved anticancer activity and synergized with the drug gefitinib to inhibit the growth and migration of A549 and NCI-H1299 lung cancer cells. Our data have demonstrated that the recombinant protein ImI-AFP3 is a promising candidate for drug development to suppress lung cancer cell growth, especially to suppress hepatoid adenocarcinoma of the lung (HAL) cell growth.
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Conotoxinas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Conotoxinas/química , Conotoxinas/metabolismo , Conotoxinas/farmacologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , PulmãoRESUMO
BACKGROUND: Radiotherapy (RT) can drive cancer cells to enter a state of cellular senescence in which cells can secrete senescence-associated secretory phenotype (SASP) and produce small extracellular vesicles (sEVs) to interact with cells in the tumor microenvironment (TME). Tumor-derived sEVs that are taken up by recipient cells contribute to cancer cell metabolic plasticity, resistance to anticancer therapy, and adaptation to the TME. However, how radiation-induced sEVs support oral squamous cell carcinoma (OSCC) progression remains unclear. METHODS: Beta-galactosidase staining and SASP mRNA expression analysis were used to evaluate the senescence-associated activity of OSCC cells after irradiation. Nanoparticle tracking analysis was performed to identify radiation-induced sEVs. Liquid chromatography-tandem mass spectrometry (LC-MS) was used to explore changes in the levels of proteins in radiation-induced sEVs. Cell Counting Kit-8 and colony formation assays were performed to investigate the function of radiation-induced SASP and sEVs in vitro. A xenograft tumor model was established to investigate the functions of radiation-induced sEVs and V-9302 in vivo as well as the underlying mechanisms. Bioinformatics analysis was performed to determine the relationship between glutamine metabolism and OSCC recurrence. RESULTS: We determined that the radiation-induced SASP triggered OSCC cell proliferation. Additionally, radiation-induced sEVs exacerbated OSCC cell malignancy. LC-MS/MS and bioinformatics analyses revealed that SLC1A5, which is a cellular receptor that participates in glutamine uptake, was significantly enriched in radiation-induced sEVs. In vitro and in vivo, inhibiting SLC1A5 could block the oncogenic effects of radiation-induced sEVs in OSCC. CONCLUSION: Radiation-induced sEVs might promote the proliferation of unirradiated cancer cells by enhancing glutamine metabolism; this might be a novel molecular mechanism underlying radiation resistance in OSCC patients.
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Carcinoma de Células Escamosas , Progressão da Doença , Exossomos , Glutamina , Neoplasias Bucais , Glutamina/metabolismo , Humanos , Neoplasias Bucais/radioterapia , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/metabolismo , Animais , Exossomos/metabolismo , Linhagem Celular Tumoral , Microambiente Tumoral , Camundongos , Antígenos de Histocompatibilidade Menor/metabolismo , Camundongos Nus , Senescência Celular , Camundongos Endogâmicos BALB C , Sistema A de Transporte de Aminoácidos/metabolismo , Sistema ASC de Transporte de Aminoácidos/metabolismoRESUMO
Antineoplastic agents that target tubulin have shown efficacy as chemotherapeutic drugs, yet they are often constrained by multidrug resistance (MDR) and unwanted side effects. A multi-targeted strategy demonstrates great potency in reducing toxicity and enhancing efficacy and provides an alternative way for attenuating MDR. In this study, a series of dual-targeted anti-cancer agents based on indole-chalcone derivatives and the camptothecin (CPT) scaffold were synthesized. Among them, 14-1 demonstrated superior anti-proliferative activity than its precursor 13-1, CPT or their physical mixtures against tested cancer cells, including multidrug-resistant variants, while exhibited moderate cytotoxicity toward human normal cells. Mechanistic studies revealed that 14-1 acted as a glutathione-responsive prodrug, inducing apoptosis by substantially enhancing intracellular uptake of CPT, inhibiting tubulin polymerization, increasing the accumulation of intracellular reactive oxygen species, and initiating a mitochondrion-dependent apoptotic pathway. Moreover, 14-1 notably induced autophagy and suppressed topoisomerase I activity to further promote apoptosis. Importantly, 14-1 displayed potent inhibitory effect on tumor growth in paclitaxel (PTX)-resistant colorectal cancer (HCT-116/PTX) xenograft models without inducing obvious toxicity compared with CPT- or combo-treated group. These results suggest that 14-1 holds promise as a novel candidate for anti-cancer therapy, particularly in PTX-resistant cancers.
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Antineoplásicos , Chalconas , Neoplasias do Colo , Pró-Fármacos , Humanos , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Camptotecina/farmacologia , Linhagem Celular Tumoral , Chalconas/farmacologia , Neoplasias do Colo/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Glutationa , Paclitaxel/farmacologia , Pró-Fármacos/farmacologia , Tubulina (Proteína)/farmacologia , Autofagia/efeitos dos fármacosRESUMO
Neutrophil extracellular traps (NETs) are implicated in gastric cancer (GC) growth, metastatic dissemination, cancer-associated thrombosis, etc. This work is conducted to elucidate the heterogeneity of NETs in GC. The transcriptome heterogeneity of NETs is investigated in TCGA-STAD via a consensus clustering algorithm, with subsequent external verification in the GSE88433 and GSE88437 cohorts. Clinical and molecular traits, the immune microenvironment, and drug response are characterized in the identified NET-based clusters. Based upon the feature genes of NETs, a classifier is built for estimating NET-based clusters via machine learning. Multiple experiments are utilized to verify the expressions and implications of the feature genes in GC. A novel NET-based classification system is proposed for reflecting the heterogeneity of NETs in GC. Two NET-based clusters have unique and heterogeneous clinical and molecular features, immune microenvironments, and responses to targeted therapy and immunotherapy. A logistic regression model reliably differentiates the NET-based clusters. The feature genes C5AR1, CSF1R, CSF2RB, CYBB, HCK, ITGB2, LILRB2, MNDA, MPEG1, PLEK, SRGN, and STAB1 are proven to be aberrantly expressed in GC cells. Specific knockdown of C5AR1 effectively hinders GC cell growth and elicits intracellular ROS accumulation. In addition, its suppression suppresses the aggressiveness and EMT phenotype of GC cells. In all, NETs are the main contributors to intratumoral heterogeneity and differential drug sensitivity in GC, and C5AR1â has been shown to trigger GC growth and metastatic spread. These findings collectively provide a theoretical basis for the use of anti-NETs in GC treatment.
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Armadilhas Extracelulares , Neoplasias Gástricas , Humanos , Armadilhas Extracelulares/metabolismo , Neutrófilos , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Fenótipo , Microambiente Tumoral/genéticaRESUMO
Porous sound absorption ceramic is one of the most promising materials for effectively eliminating noise pollution. However, its high production cost and low mechanical strength limit its practical applications. In this work, low-cost and in situ mullite whisker-reinforced porous sound-absorbing ceramics were prepared using recyclable construction waste and Al2O3 powder as the main raw materials, and AlF3 and CeO2 as the additives, respectively. The effects of CeO2 content, AlF3 content, and sintering temperature on the microstructure and properties of the porous ceramics were systematically investigated. The results showed that a small amount of CeO2 significantly promoted the growth of elongated mullite crystals in the resultant porous ceramics, decreased the growth temperature of the mullite whiskers, and significantly increased the biaxial flexural strength. When 2 wt.% CeO2 and 12 wt.% AlF3 were added to the system, mullite whiskers were successfully obtained at a sintering temperature of 1300 °C for 1 h, which exhibited excellent properties, including an open porosity of 56.4 ± 0.6%, an average pore size of 1.32-2.54 µm, a biaxial flexural strength of 23.7 ± 0.9 MPa, and a sound absorption coefficient of >0.8 at 800-4000 Hz.
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Titanium dioxide (TiO2) is widely employed in the catalytic degradation of wastewater, owing to its robust stability, superior photocatalytic efficiency, and cost-effectiveness. Nonetheless, isolating the fine particulate photocatalysts from the solution post-reaction poses a significant challenge in practical photocatalytic processes. Furthermore, these particles have a tendency to agglomerate into larger clusters, which diminishes their stability. To address this issue, the present study has developed Al2O3-SiO2-TiO2 composite semiconductor porous ceramics and has systematically explored the influence of Al2O3 and SiO2 on the structure and properties of TiO2 porous ceramics. The findings reveal that the incorporation of Al2O3 augments the open porosity of the ceramics and inhibits the aggregation of TiO2, thereby increasing the catalytic site and improving the light absorption capacity. On the other hand, the addition of SiO2 enhances the bending strength of the ceramics and inhibits the conversion of anatase to rutile, thereby further enhancing its photocatalytic activity. Consequently, at an optimal composition of 55 wt.% Al2O3, 40 wt.% TiO2, and 5 wt.% SiO2, the resulting porous ceramics exhibit a methylene blue removal rate of 91.50%, and even after undergoing five cycles of testing, their catalytic efficiency remains approximately 83.82%. These outcomes underscore the exceptional photocatalytic degradation efficiency, recyclability, and reusability of the Al2O3-SiO2-TiO2 porous ceramics, suggesting their substantial potential for application in the treatment of dye wastewater, especially for the removal of methylene blue.
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Gastric cancer is one of the most prevalent cancers worldwide, and human epidermal growth factor receptor 2 (HER2)-positive cases account for approximately 20% of the total cases. Currently, trastuzumab + chemotherapy is the recommended first-line treatment for patients with HER2-positive advanced gastric cancer, and the combination has exhibited definite efficacy in HER2-targeted therapy. However, the emergence of drug resistance during treatment considerably reduces its effectiveness; thus, it is imperative to investigate the potential mechanisms underlying resistance. In the present review article, we comprehensively introduce multiple mechanisms underlying resistance to trastuzumab in HER2-positive gastric cancer cases, aiming to provide insights for rectifying issues associated with resistance to trastuzumab and devising subsequent treatment strategies.
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Fusobacterium nucleatum colonization contributes to the occurrence of portal vein thrombosis in patients with gastric cancer (GC). However, the underlying mechanism by which F. nucleatum promotes thrombosis remains unclear. In this study, we recruited a total of 91 patients with GC and examined the presence of F. nucleatum in tumor and adjacent non-tumor tissues by fluorescence in situ hybridization and quantitative PCR. Neutrophil extracellular traps (NETs) were detected by immunohistochemistry. Extracellular vesicles (EVs) were extracted from the peripheral blood and proteins in the EVs were identified by mass spectrometry (MS). HL-60 cells differentiated into neutrophils were used to package engineered EVs to imitate the EVs released from NETs. Hematopoietic progenitor cells (HPCs) and K562 cells were used for megakaryocyte (MK) in vitro differentiation and maturation to examine the function of EVs. We observed that F. nucleatum-positive patients had increased NET and platelet counts. EVs from F. nucleatum-positive patients could promote the differentiation and maturation of MKs and had upregulated 14-3-3 proteins, especially 14-3-3ε. 14-3-3ε upregulation promoted MK differentiation and maturation in vitro. HPCs and K562 cells could receive 14-3-3ε from the EVs, which interacted with GP1BA and 14-3-3ζ to trigger PI3K-Akt signaling. In conclusion, we identified for the first time that F. nucleatum infection promotes NET formation, which releases EVs containing 14-3-3ε. These EVs could deliver 14-3-3ε to HPCs and promote their differentiation into MKs via activation of PI3K-Akt signaling.
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Vesículas Extracelulares , Infecções por Fusobacterium , Neoplasias Gástricas , Humanos , Fusobacterium nucleatum/metabolismo , Hibridização in Situ Fluorescente , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Megacariócitos/metabolismo , Megacariócitos/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Infecções por Fusobacterium/metabolismo , Infecções por Fusobacterium/microbiologia , Infecções por Fusobacterium/patologia , Vesículas Extracelulares/metabolismoRESUMO
In situ visualization of lipid composition diversity in lipid droplets (LDs) is essential for decoding lipid metabolism and function. However, effective probes for simultaneously localizing and reflecting the lipid composition of LDs are currently lacking. Here, we synthesized full-color bifunctional carbon dots (CDs) that can target LDs as well as respond to the nuance in internal lipid compositions with highly sensitive fluorescence signals, due to lipophilicity and surface state luminescence. Combined with microscopic imaging, uniform manifold approximation and projection, and sensor array concept, the capacity of cells to produce and maintain LD subgroups with varying lipid composition was clarified. Moreover, in oxidative stress cells, LDs with characteristic lipid compositions were deployed around mitochondria, and the proportion of LD subgroups changed, which gradually disappeared when treated with oxidative stress therapeutics. The CDs demonstrate great potential for in situ investigation of the LD subgroups and metabolic regulations.
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Gotículas Lipídicas , Mitocôndrias , Gotículas Lipídicas/metabolismo , Mitocôndrias/metabolismo , Metabolismo dos Lipídeos , LipídeosRESUMO
BoxCARS and pump-probe geometries are common implementations of two-dimensional infrared (2D IR) spectroscopy. BoxCARS is background-free, generally offering greater signal-to-noise ratio, which enables measuring weak vibrational echo signals. Pulse shapers have been implemented in the pump-probe geometry to accelerate data collection and suppress scatter and other unwanted signals by precise control of the pump-pulse delay and carrier phase. Here, we introduce a 2D-IR optical setup in the BoxCARS geometry that implements a pulse shaper for rapid acquisition of background-free 2D IR spectra. We show a signal-to-noise improvement using this new fast-scan BoxCARS setup versus the pump-probe geometry within the same configuration.
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BACKGROUND: Novel ADC drugs provide a new therapeutic strategy for gastric cancer.The present study aimed to analyze the clinical efficacy and drug toxicities of disitamab vedotin (RC48) plus immune checkpoint inhibitors(ICIs) and RC48 as third-line therapies and beyond for advanced and metastatic gastric cancer patients. METHODS: This was an observational multicenter real-world study.From August 2021 to January 2022,patients with HER2-positive or HER2-low advanced and metastatic gastric cancer and failed from two or more lines of prior therapy were enrolled and treated with RC48 plus ICIs or RC48. In this study, progression free survival(PFS) was the primary end point. Other evaluation indicators were objective response rate(ORR),disease control rate(DCR),overall survival(OS) and drug toxicities. RESULTS: 45 patients were enrolled,of which 25 patients received RC48 plus ICIs,20 patients received RC48.Patients who received RC48 plus ICIs obtained better ORR (36.0% vs. 10.0%, P = 0.044) and DCR (80.0% vs. 50.0%, P = 0.034) compared with RC48,and simultaneously,the median PFS in RC48 plus ICIs group were superior to RC48 group(6.2 m vs. 3.9 m).The median OS was not reached.No statistically differences were found between HER2-positive and HER2-low group with respect to ORR (27.3% vs. 16.7%, P = 0.464),DCR (66.7% vs. 66.7%, P = 1.000),median PFS(5.7 m vs. 4.3 m, P = 0.299).The most common adverse events (AEs) were decreased white blood count,decreased neutrophil count,fatigue,hypoaesthesia and alopecia.Grade 3-4 AEs occurred in 7(35.0%) patients of RC48 group and 10(40.0%) patients of RC48 plus ICIs group,respectively. CONCLUSION: Compared with RC48 monotherapy, ICIs plus RC48 demonstrated superior third-line and beyond therapeutic efficacy for HER2-positive or HER2-low advanced and metastatic gastric cancer patients with manageable safety.