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2.
Sci Total Environ ; 888: 164235, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37196939

RESUMO

Ultrafiltration (UF) is extensively used for algae removal because of its ability to retain algal cells with high efficiency, but it still faces the problem of membrane fouling and low retention capacity of dissolved organics. Hence, a strategy of coagulation with chitosan quaternary ammonium salt (HTCC) enhanced by sodium percarbonate (SPC) pre-oxidation was proposed to improve the UF performance. The fouling resistances were calculated by a resistance-in-series model based on Darcy's formula, and the membrane fouling mechanism was evaluated using a pore plugging-cake filtration model. The effect of SPC-HTCC treatment on the properties of algal foulants was explored, and the result showed that the water quality was improved with the maximum removal rates of 78.8 %, 52.4 % and 79.5 % for algal cells, dissolved organic carbon and turbidity, respectively. The SPC could achieve a mild oxidation effect that degraded the electronegative organics attached to algal cells without destroying the cell integrity, making the algal pollutants easier to agglomerate through subsequent HTCC coagulation by forming larger flocs. In terms of membrane filtration, the terminal normalized flux was increased from 0.25 to 0.71, with the reversible and irreversible resistances reduced by 90.8 % and 40.2 %, individually. The synergistic treatment reduced the accumulation of algal cells and algae-derived organics on the membrane surface as inferred from the interface fouling characteristics. The interfacial free energy analysis showed that the synergistic treatment reduced the adhesion of contaminants to the membrane surface, as well as the attraction among pollutants. Overall, the proposed process has high application prospects for algae-laden water purification.

3.
Environ Technol ; : 1-13, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37226802

RESUMO

In this study, persulphate and nanoscale zero-valent iron were activated by ultraviolet irradiation (PS/nZVI/UV), followed by formation of dynamic flocs with AlCl3-TiCl4 coagulant directly injected into a gravity-driven membrane (GDM) tank. Membrane fouling caused by typical organic matter fractions including humic acid (HA), HA together with bovine serum albumin (HA-BSA), HA combined with polysaccharide (HA-SA) and the HA-BSA-SA mixture at pH of 6.0, 7.5 and 9.0 were evaluated by specific flux and fouling resistance distribution. The results showed that GDM pre-layered with AlCl3-TiCl4 flocs exhibited the maximum specific flux, followed by AlCl3 and TiCl4. Pre-oxidation with 0.5 mM PS and 0.1 g nZVI under UV radiation for 20 min was beneficial to degrade HA and SA fraction with molecular weight >100 kDa and <30 kDa, and BSA fraction with <30 kDa. The presence of BSA attributed mostly to irreversible fouling, SA together with BAS could exacerbate irreversible fouling, while HA caused the least fouling. The irreversible resistance of a PS/nZVI/UV-GDM system was 62.79%, 27.27%, 58.03% and 49.68% lower than that of control GDM in the treatment of HA, HA-BSA, HA-SA and HA-BSA-SA, respectively. The PS/nZVI/UV-GDM system could achieve the highest foulants removal efficiency at pH of 6.0. Morphological observations confirmed the differences in biofouling layers in different water types. Over 30-day operation, the bacterial genera on the biofouling layer could affect the organic removals, while the type of organic matter that was present influenced the relative abundance of bacterial genera.

4.
Foods ; 12(9)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37174396

RESUMO

Probiotics have gained tremendous attention as an alternative to antibiotics, while synbiotics may exhibit a greater growth promoting effect than their counterpart probiotics due to the prebiotics' promotion on the growth and reproduction of probiotics. The objective of this study was to investigate the influence of Lactiplantibacillus plantarum N-1 and its synbiotic with oligomeric isomaltose on the growth performance and meat quality of Hu sheep. Hu sheep (0-3 days old) were fed with water, probiotics of N-1, or synbiotics (N-1 and oligomeric isomaltose) daily in three pens for 60 days and regularly evaluated to measure growth performance and collect serum (five lambs per group). Longissimus thoracis (LT) and biceps brachii (BB) muscle tissues were collected for the analysis of pH value, color, texture, nutrients, mineral elements, amino acids, volatile compounds, and antioxidant capacity. The results showed that dietary supplementation of N-1 tended to improve growth performance and meat quality of Hu sheep, while the synergism of N-1 with oligomeric isomaltose significantly improved their growth performance and meat quality (p < 0.05). Both the dietary supplementation of N-1 and synbiotics (p < 0.05) increased the body weight and body size of Hu sheep. Synbiotic treatment reduced serum cholesterol and improved LT fat content by increasing the transcription level of fatty acid synthase to enhance fat deposition in LT, as determined via RT-qPCR analysis. Moreover, synbiotics increased zinc content and improved LT tenderness by decreasing shear force and significantly increased the levels of certain essential (Thr, Phe, and Met) and non-essential (Asp, Ser, and Tyr) amino acids of LT (p < 0.05). Additionally, synbiotics inhibited the production of carbonyl groups and TBARS in LT and thus maintained antioxidant stability. In conclusion, it is recommended that the use of synbiotics in livestock breeding be promoted to improve sheep production and meat quality.

5.
Toxins (Basel) ; 15(5)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37235346

RESUMO

Ingestion of food toxins such as aflatoxin B1 (AFB1) during pregnancy may impair fetal neurodevelopment. However, animal model results may not be accurate due to the species' differences, and testing on humans is ethically impermissible. Here, we developed an in vitro human maternal-fetal multicellular model composed of a human hepatic compartment, a bilayer placental barrier, and a human fetal central nervous system compartment using neural stem cells (NSCs) to investigate the effect of AFB1 on fetal-side NSCs. AFB1 passed through the HepG2 hepatocellular carcinoma cells to mimic the maternal metabolic effects. Importantly, even at the limited concentration (0.0641 ± 0.0046 µM) of AFB1, close to the national safety level standard of China (GB-2761-2011), the mixture of AFB1 crossing the placental barrier induced NSC apoptosis. The level of reactive oxygen species in NSCs was significantly elevated and the cell membrane was damaged, causing the release of intracellular lactate dehydrogenase (p < 0.05). The comet experiment and γ-H2AX immunofluorescence assay showed that AFB1 caused significant DNA damage to NSCs (p < 0.05). This study provided a new model for the toxicological evaluation of the effect of food mycotoxin exposure during pregnancy on fetal neurodevelopment.


Assuntos
Aflatoxina B1 , Micotoxinas , Animais , Feminino , Gravidez , Humanos , Aflatoxina B1/toxicidade , Aflatoxina B1/metabolismo , Placenta/metabolismo , Dano ao DNA , Micotoxinas/metabolismo , Fígado/metabolismo
6.
Environ Sci Technol ; 57(15): 6188-6195, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37011377

RESUMO

The coexistence of selenite (Se(IV)) and acetylacetone (AA) generated a synergistic effect on the growth inhibition of a bloom-forming cyanobacterium, Microcystis aeruginosa. The mechanism behind this phenomenon is of great significance in the control of harmful algal blooms. To elucidate the role of Se(IV) in this effect, the reactions in ternary solutions composed of Se(IV), AA (or two other similar hydrogen donors), and quinones, especially benzoquinone (BQ), were investigated. The transformation kinetic results demonstrate that Se(IV) played a catalytic role in the reactions between AA (or ascorbic acid) and quinones. By comparison with five other oxyanions (sulfite, sulfate, nitrite, nitrate, and phosphate) and two AA derivatives, the formation of an AA-Se(IV) complexation intermediate was confirmed as a key step in the accelerated reactions between BQ and AA. To our knowledge, this is the first report on Se(IV) as a catalyst for quinone-involved reactions. Since both quinones and Se are essential in cells and there are many other chemicals of similar electron-donating properties to that of AA, the finding here shed light on the regulation of electron transport chains in a variety of processes, especially the redox balances that are tuned by quinones and glutathione.


Assuntos
Microcystis , Ácido Selenioso/farmacologia , Benzoquinonas/farmacologia , Catálise
7.
Eur J Cancer ; 186: 211-221, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37062625

RESUMO

BACKGROUND: An increasing number of clinical trials are being conducted exploring the efficacy of neoadjuvant immune checkpoint inhibitors. Surrogate end-points for overall survival (OS) are urgently needed. METHODS: Phase II or III trials of neoadjuvant immunotherapy that reported data on OS and surrogate end-points were identified from January 1, 2000, to November 25, 2022. Individual patient data, and trial-level data were requested from corresponding authors or extracted from eligible trials. At the individual level, correlations between radiological and pathological response and OS were measured by the Cox model and quantified by hazard ratio (HR). C-statistic was used to quantify the predictive performance of radiological and pathological response for OS. The coefficient of determination (R2) between RFS and OS was evaluated by a bivariate survival model. RESULTS: A total of 29 trials reporting 2901 patients were included. ORR correlated with improved OS (3-year OS: 87.0% versus 70.4% for ORR versus non-ORR, respectively; HR, 0.34, 95% confidence interval [CI], 0.17-0.68). The HRs for OS in patients achieving MPR and pCR were 0.24 (95% CI, 0.12-0.46) and 0.13 (95% CI, 0.05-0.36). The survival benefit maintained after adjusting tumour type. C-statistics of ORR, MPR and pCR were 0.63, 0.63 and 0.65, respectively. The strength of association between RFS and OS was strong (R2 = 0.88, 95% CI, 0.79-0.94). CONCLUSIONS: These findings suggest that ORR, MPR, pCR and RFS are valid predictors for OS when using neoadjuvant immune checkpoint inhibitors. Moreover, MPR, pCR and RFS may be the most optimal surrogates for OS.


Assuntos
Inibidores de Checkpoint Imunológico , Terapia Neoadjuvante , Humanos , Biomarcadores , Modelos de Riscos Proporcionais , Imunoterapia
8.
Front Microbiol ; 14: 1134517, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37007488

RESUMO

Introduction: The gut-brain axis has been widely recognized in autism spectrum disorder (ASD), and probiotics are considered to potentially benefit the rescuing of autism-like behaviors. As a probiotic strain, Lactiplantibacillus plantarum N-1(LPN-1) was utilized to investigate its effects on gut microbiota and autism-like behaviors in ASD mice constructed by maternal immune activation (MIA). Methods: Adult offspring of MIA mice were given LPN-1 at the dosage of 2 × 109 CFU/g for 4 weeks before subject to the behavior and gut microbiota evaluation. Results: The behavioral tests showed that LPN-1 intervention was able to rescue autism-like behaviors in mice, including anxiety and depression. In which the LPN-1 treatment group increased the time spent interacting with strangers in the three-chamber test, their activity time and distance in the central area increased in the open field test, and their immobility time decreased when hanging their tails. Moreover, the supplementation of LPN-1 reversed the intestinal flora structure of ASD mice by enhancing the relative abundance of the pivotal microorganisms of Allobaculum and Oscillospira, while reducing those harmful ones like Sutterella at the genus level. Discussion: These results suggested that LPN-1 supplementation may improve autism-like behaviors, possibly via regulating the gut microbiota.

9.
Methods Mol Biol ; 2641: 147-161, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37074648

RESUMO

Gasdermin B (GSDMB) and gasdermin E (GSDME) are two members of the gasdermin family, which shares a conservative gasdermin-N domain capable of executing pyroptotic cell death, through perforating the plasma membrane from inside of the cell. Both GSDMB and GSDME are autoinhibited in the resting stage and require proteolytic cleavage to unleash the pore-forming activity that otherwise is masked by their C-terminal gasdermin-C domain. GSDMB is cleaved and activated by granzyme A (GZMA) from cytotoxic T lymphocytes or natural killer cells, while GSDME is activated by caspase-3 cleavage downstream of various well-known "apoptotic" stimuli. Here, we describe the methods for inducing pyroptosis through GSDMB and GSDME cleavage.


Assuntos
Gasderminas , Piroptose , Piroptose/fisiologia , Proteólise , Células Matadoras Naturais/metabolismo , Caspase 3/metabolismo
10.
Biomed Opt Express ; 14(4): 1833-1847, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37078057

RESUMO

High-density localization based on deep learning is a very effective method to accelerate single molecule localization microscopy (SMLM). Compared with traditional high-density localization methods, deep learning-based methods enable a faster data processing speed and a higher localization accuracy. However, the reported high-density localization methods based on deep learning are still not fast enough to enable real time data processing for large batches of raw images, which is probably due to the heavy computational burden and computation complexity in the U-shape architecture used in these models. Here we propose a high-density localization method called FID-STORM, which is based on an improved residual deconvolutional network for the real-time processing of raw images. In FID-STORM, we use a residual network to extract the features directly from low-resolution raw images rather than the U-shape network from interpolated images. We also use a model fusion from TensorRT to further accelerate the inference of the model. In addition, we process the sum of the localization images directly on GPU to obtain an additional speed gain. Using simulated and experimental data, we verified that the FID-STORM method achieves a processing speed of 7.31 ms/frame at 256 × 256 pixels @ Nvidia RTX 2080 Ti graphic card, which is shorter than the typical exposure time of 10∼30 ms, thus enabling real-time data processing in high-density SMLM. Moreover, compared with a popular interpolated image-based method called Deep-STORM, FID-STORM enables a speed gain of ∼26 times, without loss of reconstruction accuracy. We also provided an ImageJ plugin for our new method.

11.
Clin Transl Radiat Oncol ; 40: 100617, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37008513

RESUMO

Background: Few studies concentrate on spleen dosimetry of radiotherapy for gastric cancer (GC). Although there is no consensus on the spleen dose-volume threshold for lymphopenia, several studies indicated that the higher the spleen dose, the higher the risk of lymphopenia. This study aimed to identify the appropriate spleen dosimetric parameters for predicting grade 4 + lymphopenia in patients with locally advanced GC. Material and methods: A total of 295 patients treated with nCRT and nChT from June 2013 to December 2021 at two major centers were included, of whom 220 were assigned to the training cohort and 75 to the external validation cohort. Results: Grade 4 + lymphopenia was more common in the nCRT than in the nChT group (49.5% vs. 0, P < 0.001 in the training cohort; 25.0% vs. 0, P = 0.001 in the external validation cohort). Age ≥ 60 years (P = 0.006), lower pretreatment absolute lymphocyte count (P = 0.001), higher spleen volume (SPV) (P = 0.001), and higher V20 (P = 0.003) were significant risk factors of grade 4 + lymphopenia for patients treated with nCRT. Patients with grade 4 + lymphopenia had significantly worse PFS (P = 0.043) and showed a negative correlation trend with OS (P = 0.07). Limiting V20 to < 84.5% could decrease the incidence of grade 4 + lymphopenia by 35.7%. The predictive effectiveness of the multivariable model in the training and external validation cohorts was 0.880 and 0.737, respectively. Conclusion: Grade 4 + lymphopenia during nCRT was more common than nChT, and was associated with a worse PFS in GC patients. Constraining the spleen V20 to < 84.5% may indirectly improve outcomes through lymphocyte preservation.

12.
Nat Commun ; 14(1): 1813, 2023 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-37002244

RESUMO

Ion mobility (IM) adds a new dimension to liquid chromatography-mass spectrometry-based untargeted metabolomics which significantly enhances coverage, sensitivity, and resolving power for analyzing the metabolome, particularly metabolite isomers. However, the high dimensionality of IM-resolved metabolomics data presents a great challenge to data processing, restricting its widespread applications. Here, we develop a mass spectrum-oriented bottom-up assembly algorithm for IM-resolved metabolomics that utilizes mass spectra to assemble four-dimensional peaks in a reverse order of multidimensional separation. We further develop the end-to-end computational framework Met4DX for peak detection, quantification and identification of metabolites in IM-resolved metabolomics. Benchmarking and validation of Met4DX demonstrates superior performance compared to existing tools with regard to coverage, sensitivity, peak fidelity and quantification precision. Importantly, Met4DX successfully detects and differentiates co-eluted metabolite isomers with small differences in the chromatographic and IM dimensions. Together, Met4DX advances metabolite discovery in biological organisms by deciphering the complex 4D metabolomics data.


Assuntos
Metaboloma , Metabolômica , Metabolômica/métodos , Espectrometria de Massas/métodos , Cromatografia Líquida , Algoritmos
13.
Nature ; 616(7957): 598-605, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36991125

RESUMO

Cytotoxic lymphocyte-derived granzyme A (GZMA) cleaves GSDMB, a gasdermin-family pore-forming protein1,2, to trigger target cell pyroptosis3. GSDMB and the charter gasdermin family member GSDMD4,5 have been inconsistently reported to be degraded by the Shigella flexneri ubiquitin-ligase virulence factor IpaH7.8 (refs. 6,7). Whether and how IpaH7.8 targets both gasdermins is undefined, and the pyroptosis function of GSDMB has even been questioned recently6,8. Here we report the crystal structure of the IpaH7.8-GSDMB complex, which shows how IpaH7.8 recognizes the GSDMB pore-forming domain. We clarify that IpaH7.8 targets human (but not mouse) GSDMD through a similar mechanism. The structure of full-length GSDMB suggests stronger autoinhibition than in other gasdermins9,10. GSDMB has multiple splicing isoforms that are equally targeted by IpaH7.8 but exhibit contrasting pyroptotic activities. Presence of exon 6 in the isoforms dictates the pore-forming, pyroptotic activity in GSDMB. We determine the cryo-electron microscopy structure of the 27-fold-symmetric GSDMB pore and depict conformational changes that drive pore formation. The structure uncovers an essential role for exon-6-derived elements in pore assembly, explaining pyroptosis deficiency in the non-canonical splicing isoform used in recent studies6,8. Different cancer cell lines have markedly different isoform compositions, correlating with the onset and extent of pyroptosis following GZMA stimulation. Our study illustrates fine regulation of GSDMB pore-forming activity by pathogenic bacteria and mRNA splicing and defines the underlying structural mechanisms.


Assuntos
Gasderminas , Proteínas Citotóxicas Formadoras de Poros , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Microscopia Crioeletrônica , Cristalografia por Raios X , Gasderminas/química , Gasderminas/genética , Gasderminas/metabolismo , Gasderminas/ultraestrutura , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/ultraestrutura , Proteínas Citotóxicas Formadoras de Poros/química , Proteínas Citotóxicas Formadoras de Poros/genética , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Proteínas Citotóxicas Formadoras de Poros/ultraestrutura , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/ultraestrutura , Piroptose , Shigella flexneri , Especificidade da Espécie , Processamento Alternativo
15.
J Hazard Mater ; 449: 131065, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-36840988

RESUMO

The physicochemical properties of powdered activated carbon (PAC) are important factors affecting its adsorption performance, which is also related to the characteristics of target organic pollutants. In this study, the key indicators affecting the adsorption performance of PAC were identified, and the physicochemical properties of PACs were modified by hydrogen peroxide and/or ultrasound in a targeted manner to improve the adsorption performance. The results indicated the adsorption properties of printing and dyeing secondary effluent organic matter (EfOM) in terms of CODcr and UV absorbance at 254 nm (UV254) positively correlated with mesoporous volume, average pore size and acid group content of PAC. After modification, the mesoporous volume and average pore size of PAC increased, and the number of acidic groups increased, thus enhancing the adsorption efficiency. EfOM removal characteristics showed that PAC preferentially adsorbed unsaturated bonds or aromatic compounds, tryptophan-like proteins, soluble microbial metabolites and low molecular weight fractions below 1 kDa. In addition, the relative contents of specific surface area, pore volume and oxygen-containing functional groups (O-CO, C-OH, CO/O-C-O) of PAC decreased after adsorption, indicating that EfOM adsorption was a physical and chemical process, including pore filling, hydrophobic interaction and chemical bond force interaction. In general, PACs with larger mesoporous volume, average pore size and abundant acid groups possessed good adsorption performance towards EfOM.

16.
AAPS PharmSciTech ; 24(2): 69, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36792796

RESUMO

In order to better promote the application of the polymeric mixed micelles (PMMs) in oral delivery, in addition to focusing on the improvement of micellar structural stability, it is necessary to obtain the absorption characteristics of the intact micellar particles. In this work, the transport behavior across Caco-2 cells of FS/PMMs composed of Pluronic F127 and Solutol HS15 was tracked by encapsulating an environment-responsive probe into the particles. The specific property of the probe is the water-initiated aggregation-caused quenching (ACQ) ability, by which integral particles can be identified accurately. The influence of polymeric ratios (FS) on the transcellular behavior of FS/PMMs was explored and the single pass intestinal perfusion experiment was used to further illustrate it. Moreover, pharmacokinetics parameters were detected to analyze the relationship among FS ratios, transport behavior, and pharmacokinetic parameters. FS ratios were found to hardly affect the endocytosis pathways and intracellular itinerary of FS/PMMs, but do affect the proportion of each path. FS/PMMs with high HS15 content, namely System-I, were found to primarily undergo receptor-mediated endocytosis pathway and be less susceptible to lysosomal degradation, which would lead to more absorption and higher Cmax and AUC than drug suspension. In contrast, despite System-II with high F127 content cannot contribute to drug plasma concentration, it can prolong the in vivo retention time. These findings provided evidence for the role of polymeric ratios in modulating the transcellular absorption and pharmacokinetic parameters of the drug-loaded PMMs, and would be a step forward in helping PMMs' design to enhance oral drug delivery.


Assuntos
Sistemas de Liberação de Medicamentos , Micelas , Humanos , Células CACO-2 , Polímeros/química , Poloxâmero/química , Transcitose , Portadores de Fármacos/química
17.
Food Chem ; 409: 135195, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-36571901

RESUMO

Growing evidence suggests that polyphenols could mitigate type 2 diabetes mellitus (T2DM). The glucose-regulatory effects of protein-bound polyphenols, however, have been rarely studied. In this study, macrogenomic and metabolomic analyses were applied to investigate the modulation of myofibrillar protein-chlorogenic acid (MP-CGA) complexes on T2DM rats from the gut microbiota perspective. Results showed that MP-CGA improved hyperglycemia and hyperlipidemia, decreased intestinal inflammation, and reduced intestinal barrier injury. MP-CGA reconstructed gut microbiota in T2DM rats, elevating the abundance of probiotics Bacteroides, Akkermansia, and Parabacteroides while suppressing opportunistic pathogens Enterococcus and Staphylococcus. MP-CGA significantly elevated the concentrations of intestinal metabolites like butyric acid that positively regulate T2DM and reduced the secondary bile acids contents. Therefore, MP-CGA modulated the gut microbiota and related metabolites to maintain stable blood glucose in T2DM rats, providing new insights into the application of protein-polyphenol complexes in foods.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Ratos , Animais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Ácido Clorogênico/farmacologia , Glicemia , Polifenóis/farmacologia
18.
Mol Ther ; 30(2): 621-631, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-34547468

RESUMO

Cancer cells evade immune detection via programmed cell death 1/programmed cell death-ligand 1 (PD-1/PD-L1) interactions that inactivate T cells. PD-1/PD-L1 blockade has become an important therapy in the anti-cancer armamentarium. However, some patients do not benefit from PD-1/PD-L1 blockade despite expressing PD-L1. Here, we screened 101 gastric cancer (GC) patients at diagnosis and 141 healthy control subjects and reported one such subpopulation of GC patients with rs17718883 polymorphism in PD-L1, resulting in a nonsense P146R mutation. We detected rs17718883 in 44% of healthy control subjects, and rs17718883 was associated with a low susceptibility to GC and better prognosis in GC patients. Structural analysis suggests that the mutation weakens the PD-1:PD-L1 interaction. This was supported by co-culture experiments of T cells, with GC cells showing that the P146R substitution results in interferon (IFN)-γ secretion by T cells and enables T cells to suppress GC cell growth. Similar results with animal gastric tumor models were obtained in vivo. PD-1 monoclonal antibody treatment did not enhance the inhibitory effect of T cells on GC cells expressing PD-L1P146Rin vitro or in vivo. This study suggests that rs17718883 is common and may be used as a biomarker for exclusion from PD-1/PD-L1 blockade therapy.


Assuntos
Neoplasias Gástricas , Animais , Antígeno B7-H1/metabolismo , Humanos , Imunoterapia , Prognóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/terapia , Linfócitos T/metabolismo
19.
JAMA Netw Open ; 5(12): e2245836, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36484990

RESUMO

Importance: The E-cadherin gene, CDH1, and the α-E-catenin gene, CTNNA1, were previously identified as hereditary diffuse gastric cancer (HDGC) susceptibility genes, explaining 25% to 50% of HDGC cases. The genetic basis underlying disease susceptibility in the remaining 50% to 75% of patients with HDGC is still unknown. Objective: To assess the incidence rate of CDH1 germline alterations in HDGC, identify new susceptibility genes that can be used for screening of HDGC, and provide a genetic landscape for HDGC. Design, Setting, and Participants: This cohort study conducted retrospective whole-exome and targeted sequencing of 284 leukocyte samples and 186 paired tumor samples from Chinese patients with HDGC over a long follow-up period (median, 21.7 [range, 0.6-185.9] months). Among 10 431 patients diagnosed with gastric cancer between January 1, 2002, and August 31, 2018, 284 patients who met the criteria for HDGC were included. Data were analyzed from August 1 to 30, 2020. Main Outcomes and Measures: Incidence rate of CDH1 germline alterations, identification of new HDGC susceptibility genes, and genetic landscape of HDGC. Results: Among 284 Chinese patients, 161 (56.7%) were female, and the median age was 35 (range, 20-75) years. The frequency of CDH1 germline alterations was 2.8%, whereas the frequency of CDH1 somatic alterations was 25.3%. The genes with the highest incidence (>10%) of private germline alterations (including insertions and deletions) in the HDGC cohort were MUC4, ABCA13, ZNF469, FCGBP, IGFN1, RNF213, and SSPO, whereas previously reported germline alterations of CTNNA1, BRCA2, STK11, PRSS1, ATM, MSR1, PALB2, BRCA1, and RAD51C were observed at low frequencies (median, 4 [range, 1-12] cases). Furthermore, enrichment of the somatic variant signature of exposure to aflatoxin suggested potential interaction between genetics and environment in HDGC. Double-hit events in genes such as CACNA1D were observed, which suggested that these events might serve as important mechanisms for HDGC tumorigenesis. In addition, germline variants of FSIP2, HSPG2, and NCKAP5 and somatic alterations of FGFR3, ASPSCR1, CIC, DGCR8, and LZTR1 were associated with poor overall survival among patients with HDGC. Conclusions and Relevance: This study provided a genetic landscape for HDGC. The study's findings challenged the previously reported high germline alteration rate of CDH1 in HDGC and identified new potential susceptibility genes. Analyses of variant signatures and double-hit events revealed potentially important mechanisms for HDGC tumorigenesis. Findings from the present study may provide helpful information for further investigations of HDGC.


Assuntos
Adenocarcinoma , MicroRNAs , Neoplasias Gástricas , Adulto , Feminino , Humanos , Masculino , Adenosina Trifosfatases/genética , Estudos de Coortes , População do Leste Asiático , Sequenciamento do Exoma , Predisposição Genética para Doença/genética , Linhagem , Estudos Retrospectivos , Proteínas de Ligação a RNA/genética , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/genética , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases/genética , Adulto Jovem , Pessoa de Meia-Idade , Idoso
20.
BMC Cancer ; 22(1): 1154, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36348289

RESUMO

BACKGROUND: The prognosis of patients with gastric cancer (GC) with gastric outlet obstruction (GOO) after gastrectomy is highly variable. In this study, we aimed to develop a nomogram to predict the prognosis of these patients. PATIENTS AND METHODS: Data from 218 GC patients with GOO who underwent gastrectomy at Sun Yat-sen University Cancer Center were retrospectively collected as a training cohort. The data of 59 patients with the same diagnosis who underwent gastrectomy at the First Affiliated Hospital of Guangxi Medical University were collected as an external verification cohort. A nomogram for the overall survival (OS) was developed using the Cox regression model in the training cohort, which was validated in a verification cohort. RESULTS: Multivariate analysis showed that the surgical procedure (P < 0.001), period of chemotherapy (P < 0.001), T stage (P = 0.006), N stage (P = 0.040), systemic immune-inflammatory index (SII) (P < 0.001), and fibrinogen level (P = 0.026) were independent factors affecting OS. The nomogram constructed on the aforementioned factors for predicting the 1- and 3-year OS achieved a Harrell's concordance index (C-index) of 0.756 and 0.763 for the training and verification cohorts, respectively. Compared with the 8th American Joint Committee on Cancer (AJCC) Tumour-Node-Metastasis (TNM) staging system, the nomogram had higher C-index values and areas under the curve (AUCs) and slightly higher net clinical benefit. CONCLUSION: Compared to the 8th AJCC staging system, the newly developed nomogram showed superior performance in predicting the survival of GC patients with GOO after gastrectomy.


Assuntos
Obstrução da Saída Gástrica , Neoplasias Gástricas , Humanos , Nomogramas , Neoplasias Gástricas/complicações , Neoplasias Gástricas/cirurgia , Estudos Retrospectivos , China/epidemiologia , Prognóstico , Obstrução da Saída Gástrica/etiologia , Obstrução da Saída Gástrica/cirurgia , Estadiamento de Neoplasias
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