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The Berry curvature in the band structure of transition metal dichalcogenides (TMDs) introduces a valley-dependent effective magnetic field, which induces the valley Hall effect (VHE). Similar to the ordinary Hall effect, the VHE spatially separates carriers or excitons, depending on their valley index, and accumulates them at opposite sample edges. The VHE can play a key role in valleytronic devices, but previous observations of the VHE have been limited to cryogenic temperatures. Here, we report a demonstration of the VHE of interlayer excitons in a MoS2/WSe2 heterostructure at room temperature. We monitored the in-plane propagation of interlayer excitons through photoluminescence mapping and observed their spatial separation into two opposite transverse directions that depended on the valley index of the excitons. Our theoretical simulations reproduced the salient features of these observations. Our demonstration of the robust interlayer exciton VHE at room temperature, enabled by their intrinsically long lifetimes, will open up realistic possibilities for the development of opto-valleytronic devices based on TMD heterostructures.
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LncRNA RP11-363E7.4 has been shown to be downregulated in gastric cancer (GC), while the effect of lncRNA RP11-363E7.4 on GC and its potential molecular mechanisms is unclear. The purpose of this study was to explore the functional role and underlying molecular mechanisms of lncRNA RP11-363E7.4 involved in GC progress.To address the question, quantitative real-time PCR assay was performed to confirm lncRNA RP11-363E7.4 expression levels in GC tissues and cell lines. Cell proliferation, apoptosis, migration and invasion were estimated using Cell Counting Kit-8, colony formation, scratch wound healing and Transwell assays. Potential molecular mechanisms were evaluated using western blot assay. The results showed that lncRNA RP11-363E7.4 was significantly downregulated in GC cell lines and 82 paired tissues. The correlation between expression and clinicopathological features indicated that low expression of lncRNA RP11-363E7.4 was associated with T stage (P = .010). Functional experiments showed that overexpression of lncRNA RP11-363E7.4 prevented proliferation, migration, and invasion and induced apoptosis of GC cells. Western blot assay revealed that lncRNA RP11-363E7.4 functioned via the p53, Bax/Bcl-2, ß-catenin pathway. In summary, this study revealed that lncRNA RP11-363E7.4 functioned as a tumour suppressor by inhibiting proliferation, migration, and invasion and inducing apoptosis of GC cells. Significance of the study:LncRNA RP11-363E7.4 has been shown to be downregulated in GC, while the effect of lncRNA RP11-363E7.4 on GC and its potential molecular mechanism is unclear. We revealed that lncRNA RP11-363E7.4 functioned as a tumour suppressor by inhibiting proliferation, migration, and invasion and inducing apoptosis of GC cells. LncRNA RP11-363E7.4 might become an attractive diagnostic and prognostic biomarker of GC and a promising target for GC treatment.
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Proliferação de Células , RNA Longo não Codificante/metabolismo , Neoplasias Gástricas/patologia , Apoptose , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Regulação para Baixo , Transição Epitelial-Mesenquimal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , RNA Longo não Codificante/genética , Neoplasias Gástricas/genética , beta Catenina/metabolismoRESUMO
Metal ions exert pivotal functions within the human body, encompassing essential roles in upholding cell structure, gene expression regulation, and catalytic enzyme activity. Additionally, they significantly influence various pathways implicated in divergent mechanisms of cell death. Among the prevailing malignant tumors of the digestive tract worldwide, gastric cancer stands prominent, exhibiting persistent high mortality rates. A compelling body of evidence reveals conspicuous ion irregularities in tumor tissues, encompassing gastric cancer. Notably, metal ions have been observed to elicit distinct contributions to the progression, drug resistance, and biological attributes of gastric cancer. This review consolidates pertinent literature on the involvement of metal ions in the etiology and advancement of gastric cancer. Particular attention is directed towards metal ions, namely, Na, K, Mg, Ca, Fe, Cu, Zn, and Mn, elucidating their roles in the initiation and progression of gastric cancer, cellular demise processes, drug resistance phenomena, and therapeutic approaches.
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The advent of 2D ferroelectrics, characterized by their spontaneous polarization states in layer-by-layer domains without the limitation of a finite size effect, brings enormous promise for applications in integrated optoelectronic devices. Comparing with semiconductor/insulator devices, ferroelectric devices show natural advantages such as non-volatility, low energy consumption and high response speed. Several 2D ferroelectric materials have been reported, however, the device implementation particularly for optoelectronic application remains largely hypothetical. Here, the linear electro-optic effect in 2D ferroelectrics is discovered and electrically tunable 2D ferroelectric metalens is demonstrated. The linear electric-field modulation of light is verified in 2D ferroelectric CuInP2S6. The in-plane phase retardation can be continuously tuned by a transverse DC electric field, yielding an effective electro-optic coefficient rc of 20.28 pm V-1. The CuInP2S6 crystal exhibits birefringence with the fast axis oriented along its (010) plane. The 2D ferroelectric Fresnel metalens shows efficacious focusing ability with an electrical modulation efficiency of the focusing exceeding 34%. The theoretical analysis uncovers the origin of the birefringence and unveil its ultralow light absorption across a wide wavelength range in this non-excitonic system. The van der Waals ferroelectrics enable room-temperature electrical modulation of light and offer the freedom of heterogeneous integration with silicon and another material system for highly compact and tunable photonics and metaoptics.
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Exposure to a growth factor abundant milieu has remarkable regenerative and rejuvenating effects on organ diseases, tissue damage, and regeneration, including skeletal system defects and bone regeneration. Although the introduction of candidate growth factors into relevant fields has been reported, their regenerative effects remain unsatisfactory, mainly because of the experimental challenges with limited types of growth factors, elusive dosage adjustment, and asynchronous stem cell activation with cytokine secretion. Here, an innovative hydrogel recapitulating a growth factor-enriched microenvironment (GEM) for regenerative advantage, is reported. This sulfated hydrogel includes bone morphogenetic protein-2 (BMP-2), an essential growth factor in osteogenesis, to direct mesenchymal stem cell (MSC) differentiation, stimulate cell proliferation, and improve bone formation. The semi-synthetic hydrogel, sulfonated gelatin (S-Gelatin), can amplify BMP-2 signaling in mouse MSCs by enhancing the binding between BMP-2 and BMP-2 type II receptors (BMPR2), which are located on MSC nuclei and activated by the hydrogel. Importantly, the dramatically improved cytokine secretion of MSCs throughout regeneration confirms the growth factor-acquiring potential of S-Gelatin/rhBMP-2 hydrogel, leading to the vascularization enhancement. These findings provide a new strategy to achieve an in situ GEM and accelerated bone regeneration by amplifying the regenerative capacity of rhBMP-2 and capturing endogenous growth factors.
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Surface enhanced Resonance Raman spectroscopy (SERRS) is a powerful technique for enhancing Raman spectra by matching the laser excitation wavelength with the plasmonic resonance and the absorption peak of biomolecules. Here, we propose a tunable Tamm plasmon polariton (TPP) cavity based on a metal on distributed Bragg reflector (DBR) as a scalable sensing platform for SERRS. We develop a gold film-coated ultralow-loss phase change material (Sb2S3) based DBR, which exhibits continuously tunable TPP resonances in the optical wavelengths. We demonstrate SERRS by matching the TPP resonance with the absorption peak of the chromophore molecule at 785 nm wavelength. We use this platform to detect cardiac Troponin I protein (cTnI), a biomarker for early diagnosis of cardiovascular disease, achieving a detection limit of 380 fM. This scalable substrate shows great promise as a next-generation tunable biosensing platform for detecting disease biomarkers in body fluids for routine real-time clinical diagnosis.
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Ouro , Análise Espectral Raman , Ouro/química , Ressonância de Plasmônio de Superfície/métodosRESUMO
Two-dimensional (2D) materials including graphene, transition metal dichalcogenides, black phosphorus, MXenes, and semimetals have attracted extensive and widespread interest over the past years for their many intriguing properties and phenomena, underlying physics, and great potential for applications. The vast library of 2D materials and their heterostructures provides a diverse range of electrical, photonic, mechanical, and chemical properties with boundless opportunities for photonics and plasmonic devices. The infrared (IR) regime, with wavelengths across 0.78 µm to 1000 µm, has particular technological significance in industrial, military, commercial, and medical settings while facing challenges especially in the limit of materials. Here, we present a comprehensive review of the varied approaches taken to leverage the properties of the 2D materials for IR applications in photodetection and sensing, light emission and modulation, surface plasmon and phonon polaritons, non-linear optics, and Smith-Purcell radiation, among others. The strategies examined include the growth and processing of 2D materials, the use of various 2D materials like semiconductors, semimetals, Weyl-semimetals and 2D heterostructures or mixed-dimensional hybrid structures, and the engineering of light-matter interactions through nanophotonics, metasurfaces, and 2D polaritons. Finally, we give an outlook on the challenges in realizing high-performance and ambient-stable devices and the prospects for future research and large-scale commercial applications.
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Localized interlayer excitons (LIXs) in two-dimensional moiré superlattices exhibit sharp and dense emission peaks, making them promising as highly tunable single-photon sources. However, the fundamental nature of these LIXs is still elusive. Here, we show the donor-acceptor pair (DAP) mechanism as one of the origins of these excitonic peaks. Numerical simulation results of the DAP model agree with the experimental photoluminescence spectra of LIX in the moiré MoSe2/WSe2 heterobilayer. In particular, we find that the emission energy-lifetime correlation and the nonmonotonic power dependence of the lifetime agree well with the DAP IX model. Our results provide insight into the physical mechanism of LIX formation in moiré heterostructures and pave new directions for engineering interlayer exciton properties in moiré superlattices.
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Pancreatic cancer is characterized by hidden onset, high malignancy, and early metastasis. Although a few cases meet the surgical indications, chemotherapy remains the primary treatment, and the resulting chemoresistance has become an urgent clinical problem that needs to be solved. In recent years, the importance of metabolic reprogramming as one of the hallmarks of cancers in tumorigenesis has been validated. Metabolic reprogramming involves glucose, lipid, and amino acid metabolism and interacts with oncogenes to affect the expression of key enzymes and signaling pathways, modifying the tumor microenvironment and contributing to the occurrence of drug tolerance. Meanwhile, the mitochondria are hubs of the three major nutrients and energy metabolisms, which are also involved in the development of drug resistance. In this review, we summarized the characteristic changes in metabolism during the progression of pancreatic cancer and their impact on chemoresistance, outlined the role of the mitochondria, and summarized current studies on metabolic inhibitors.
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Tumor microenvironment is the general term for all non-cancer components and their metabolites in tumor tissue. These components include the extracellular matrix, fibroblasts, immune cells, and endothelial cells. In the early stages of tumors, the tumor microenvironment has a tumor suppressor function. As the tumor progresses, tumor immune tolerance is induced under the action of various factors, such that the tumor suppressor microenvironment is continuously transformed into a tumor-promoting microenvironment, which promotes tumor immune escape. Eventually, tumor cells manifest the characteristics of malignant proliferation, invasion, metastasis, and drug resistance. In recent years, stress effects of the extracellular matrix, metabolic and phenotypic changes of innate immune cells (such as neutrophils, mast cells), and adaptive immune cells in the tumor microenvironment have been revealed to mediate the emerging mechanisms of immune tolerance, providing us with a large number of emerging therapeutic targets to relieve tumor immune tolerance. Gastric cancer is one of the most common digestive tract malignancies worldwide, whose mortality rate remains high. According to latest guidelines, the first-line chemotherapy of advanced gastric cancer is the traditional platinum and fluorouracil therapy, while immunotherapy for gastric cancer is extremely limited, including only Human epidermal growth factor receptor 2 (HER-2) and programmed death ligand 1 (PD-L1) targeted drugs, whose benefits are limited. Clinical experiments confirmed that cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), vascular endothelial growth factor receptor (VEGFR) and other targeted drugs alone or in combination with other drugs have limited efficacy in patients with advanced gastric cancer, far less than in lung cancer, colon cancer, and other tumors. The failure of immunotherapy is mainly related to the induction of immune tolerance in the tumor microenvironment of gastric cancer. Therefore, solving the immune tolerance of tumors is key to the success of gastric cancer immunotherapy. In this study, we summarize the latest mechanisms of various components of the tumor microenvironment in gastric cancer for inducing immune tolerance and promoting the formation of the malignant phenotype of gastric cancer, as well as the research progress of targeting the tumor microenvironment to overcome immune tolerance in the treatment of gastric cancer.
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Neoplasias Gástricas , Microambiente Tumoral , Humanos , Células Endoteliais/patologia , Fator A de Crescimento do Endotélio Vascular/farmacologia , Tolerância ImunológicaRESUMO
In hyperglycemia patients, suffering from insufficient vascularization and vascular network lesion, tissue regeneration, such as bone repair, is limited and maybe delayed by the secondary injury and hyperglycemic microenvironment. Typically, dental therapies involving guided bone regeneration is facing a difficult condition in the patients with diabetes. In this study, a hybrid membrane was endowed with biomimetic function to create an angiogenesis-inductive microenvironment by calcium ion release to overcome the limitations of bone tissue regeneration in diabetic patients. Biomineralized calcium resource was Janus-structured onto the surface of hybrid hydrogel by layer-by-layer technique to enhance vascularization and improve the bone regeneration in this study. The release of calcium ions from mineralized phases was controlled by the solubility of inorganic phases and the degradation of gels, promoting HIF-1α expression and creating a key role in angiogenesis stimulation. With highly enhanced calcium signaling and blood vessel formation, the hybrid hydrogel membranes improved the recruitment, proliferation and differentiation of mesenchymal stem cells and endothelial progenitors, confirmed by the enhancement of microvascular regeneration and new bone formation in the critical-sized calvarial defect in diabetic model in vivo. Our study demonstrates a translational potential of hybrid hydrogels engineered with inorganic minerals for orthopedic applications in hyperglycemia.
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Hidrogéis , Hiperglicemia , Regeneração Óssea , Cálcio , Humanos , Hidrogéis/farmacologia , OsteogêneseRESUMO
Optoelectronic materials that allow on-chip integrated light signal emitting, routing, modulation, and detection are crucial for the development of high-speed and high-throughput optical communication and computing technologies. Interlayer excitons in 2D van der Waals heterostructures, where electrons and holes are bounded by Coulomb interaction but spatially localized in different 2D layers, have recently attracted intense attention for their enticing properties and huge potential in device applications. Here, a general view of these 2D-confined hydrogen-like bosonic particles and the state-of-the-art developments with respect to the frontier concepts and prototypes is presented. Staggered type-II band alignment enables expansion of the interlayer direct bandgap from the intrinsic visible in monolayers up to the near- or even mid-infrared spectrum. Owing to large exciton binding energy, together with ultralong lifetime, room-temperature exciton devices and observation of quantum behaviors are demonstrated. With the rapid advances, it can be anticipated that future studies of interlayer excitons will not only allow the construction of all-exciton information processing circuits but will also continue to enrich the panoply of ideas on quantum phenomena.
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Bone regeneration and vascularization have presented a clinical challenge for decades. Considering the importance of stem cells, such as mesenchymal stem cells (MSCs), in bone regeneration, endothelial progenitor cells (EPCs) are crucial during bone repair. This paper presented sulfated chitosan (SCS)-based hydrogel scaffolds to accelerate bone tissue regeneration, vascularization enhancement, and improve bone repair. Thus, these scaffolds played a crucial role in the regeneration of blood vessels, with the increased presentation of epithelial progenitors and immune cells in this microenvironment. In vivo experiments showed that the biological impact of SCS was critical for angiogenesis and vascularization, in conjunction with bone morphogenetic protein-2 (BMP-2) and MSCs. Therefore, the BMP-2-/hydrogel system established in this study promoted angiogenesis, stimulated MSC proliferation, and enhanced bone tissue formation. In addition, this paper highlighted the angiogenic role of SCS in creating a micro-environment for effective bone repair and provides insight into the future development of new bone regeneration material.
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Quitosana , Osteogênese , Regeneração Óssea , Quitosana/farmacologia , Hidrogéis/farmacologia , Neovascularização Fisiológica , Sulfatos/farmacologia , Alicerces TeciduaisRESUMO
Exciton is a bosonic quasiparticle consisting of a pair of electron and hole, with promising potentials for optoelectronic device applications, such as exciton transistors, photodetectors and light emitting devices. However, the charge-neutral nature of excitons renders them challenging to manipulate using electronics. Here we present the generation of trions, a form of charged excitons, together with enhanced exciton resonance in monolayer WSe2. The excitation of the trion quasiparticles is achieved by the hot carrier transport from the integrated gold plasmonic nanocavity, formed by embedding monolayer WSe2 between gold nanoparticles and a gold film. The nanocavity-induced negatively charged trions provide a promising route for the manipulation of excitons, essential for the construction of all-exciton information processing circuits.
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Gastric cancer is one of the most frequently diagnosed malignant tumors, with rapid progression and poor prognosis. The role of chondroitin sulfate synthase 1 (CHSY1) in the development and progression of gastric cancer was explored and clarified in this study. The immunohistochemistry analysis of clinical tissue samples as well as data mining of public database showed that CHSY1 was significantly upregulated in gastric cancer and associated with more advanced tumor stage and poorer prognosis. In vitro loss-of-function experiments demonstrated the inhibited cell proliferation, colony formation, cell migration, as well as the promoted cell apoptosis by CHSY1 knockdown. Moreover, recovery of CHSY1 expression could attenuate the regulatory effects induced by CHSY1 knockdown. Correspondingly, gastric cancer cells with CHSY1 knockdown showed reduced tumorigenicity and slower tumor growth in vivo. In conclusion, this study identified CHSY1 as a tumor promotor in gastric cancer, which may be utilized as a novel indicator of patients' prognosis and therapeutic target for developing more effective drug for GC treatment.
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Apoptose/genética , Carcinogênese/metabolismo , Movimento Celular/genética , Proliferação de Células/genética , Glucuronosiltransferase/metabolismo , Enzimas Multifuncionais/metabolismo , N-Acetilgalactosaminiltransferases/metabolismo , Neoplasias Gástricas/metabolismo , Regulação para Cima/genética , Idoso , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes/métodos , Glucuronosiltransferase/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Enzimas Multifuncionais/genética , N-Acetilgalactosaminiltransferases/genética , Prognóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Transfecção/métodos , Carga Tumoral/genética , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
BACKGROUND: Interferon-induced transmembrane proteins (IFITMs) are a family of proteins which functions mainly include controlling cell proliferation, promoting homotypic cell adhesion, and preventing viral infection. This research study attempts to elucidate the association between IFITM10 expression level and gastric cancer (GC). METHODS: Transcriptome sequencing and clinical information on GC and normal tissues was obtained from the Cancer Genome Atlas (TCGA) database. R and related statistical packages were used to analyze the relationship between IFITM10 and survival in GC patients based on available clinical information. Receiver operating characteristic curves (ROC) were constructed using the SPSS software package. IFITM10 expression levels in patients tissue samples were examined by qPCR and association between IFITM10 expression and clinic characteristics was analyzed using SPSS. The signaling pathway associated with IFITM10 was analyzed using gene set enrichment analysis (GSEA). RESULTS: In the TCGA database, IFITM10 was highly expressed in GC tissues (P<0.001). Area under the curve (AUC) value for IFITM10 in all samples was 0.813, while AUC value in the paired GC and adjacent tissues was 0.955. In the sample of surgical patients, IFITM10 was highly expressed in GC tissues (P<0.001). IFITM10 expression was higher in T1 and T2 tissues (P=0.042), male patients (P=0.031), and tissues without neuro infiltration (P=0.008). CONCLUSIONS: IFITM10 is highly expressed in GC and can serve as an early diagnostic indicator. High expression of IFITM10 was related to a low T stage in GC.
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Nonlinear responses in transport measurements are linked to material properties not accessible at linear order1 because they follow distinct symmetry requirements2-5. While the linear Hall effect indicates time-reversal symmetry breaking, the second-order nonlinear Hall effect typically requires broken inversion symmetry1. Recent experiments on ultrathin WTe2 demonstrated this connection between crystal structure and nonlinear response6,7. The observed second-order nonlinear Hall effect can probe the Berry curvature dipole, a band geometric property, in non-magnetic materials, just like the anomalous Hall effect probes the Berry curvature in magnetic materials8,9. Theory predicts that another intrinsic band geometric property, the Berry-connection polarizability tensor10, gives rise to higher-order signals, but it has not been probed experimentally. Here, we report a third-order nonlinear Hall effect in thick Td-MoTe2 samples. The third-order signal is found to be the dominant response over both the linear- and second-order ones. Angle-resolved measurements reveal that this feature results from crystal symmetry constraints. Temperature-dependent measurement shows that the third-order Hall response agrees with the Berry-connection polarizability contribution evaluated by first-principles calculations. The third-order nonlinear Hall effect provides a valuable probe for intriguing material properties that are not accessible at lower orders and may be employed for high-order-response electronic devices.
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Optoelectronic devices that allow rerouting, modulation, and detection of the optical signals would be extremely beneficial for telecommunication technology. One of the most promising platforms for these devices is excitonic devices, as they offer very efficient coupling to light. Of especial importance are those based on indirect excitons because of their long lifetime. Here, we demonstrate excitonic transistor and router based on bilayer WSe2 Because of their strong dipole moment, excitons in bilayer WSe2 can be controlled by transverse electric field. At the same time, unlike indirect excitons in artificially stacked heterostructures based on transition metal dichalcogenides, naturally stacked bilayers are much simpler in fabrication.
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Gastric cancer (GC) is one of the most prevalent and malignant types of cancer worldwide. In China, it is the second most common type of cancer and the malignancy with the highest incidence and mortality rate. Chemotherapy for GC is not always effective due to the development of drug resistance. Drug resistance, which is frequently observed in GC, undermines the success rate of chemotherapy and the survival of patients with GC. The dysregulation of noncoding RNAs (ncRNAs), primarily microRNAs (miRNAs or miRs) and long noncoding RNAs (lncRNAs), is involved in the development of GC drug resistance via numerous mechanisms. These mechanisms contribute to the involvement of a large and complex network of ncRNAs in drug resistance. In this review, we focus on and summarize the latest research on the specific mechanisms of action of miRNAs and lncRNAs that modulate drug resistance in GC. In addition, we discuss future prospects and clinical applications of ncRNAs as potential targeted therapies against the chemoresistance of GC.
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Resistencia a Medicamentos Antineoplásicos , MicroRNAs/genética , RNA Longo não Codificante/genética , Neoplasias Gástricas/genética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , China , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Gástricas/tratamento farmacológicoRESUMO
The Warburg effect in tumor cells involves the uptake of high levels of glucose, enhanced glycolysis, and the metabolism of pyruvate to lactic acid rather than oxidative phos-phorylation to generate energy under aerobic conditions. This effect is closely related to the occurrence, invasion, metastasis, drug resistance, and poor prognosis of gastric cancer (GC). Current research has further demonstrated that the Warburg effect in GC cells is not only mediated by the glycolysis pathway, but also includes roles for mitochondria, noncoding RNAs, and other proteins that do not directly regulate metabolism. As a result, changes in the glycolysis pathway not only lead to abnormal glucose metabolism, but they also affect mitochondrial functions, cellular processes such as apoptosis and cell cycle regulation, and the metabolism of lipids and amino acids. In this review, we discuss metabolic reprogramming in GC based on glycolysis, a possible link between glucose metabolism, lipid metabolism, and amino acid metabolism, and we clarify the role of mitochondria. We also examine recent studies of metabolic inhibitors in GC.