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It is a hot problem in epilepsy research to detect and predict seizures by EEG signals. Clinically, it is generally observed that there are only sudden abnormal signals during the ictal stage, but there is no significant difference in the EEG signal between the interictal and preictal stages. To solve the problem that preictal signals are difficult to recognize clinically, and then effectively improve the recognition efficiency of epileptic seizures, so, in this paper, some nonlinear methods are comprehensively used to extract the hidden information in the EEG signals in different stages, namely, phase space reconstruction (PSR), Poincaré section (PS), synchroextracting transform (SET) and machine learning for EEG signal analysis. Firstly, PSR based on C-C method is used, and the results show that there are different diffuse attractor trajectories of the signals in different stages. Secondly, the confidence ellipse (CE) is constructed by using the scatter diagram of the corresponding trajectory on PS, and the aspect ratio and area of the ellipse are calculated. The results show that there is an interesting transitional phenomenon in preictal stage. To recognize ictal and preictal signals, time-frequency (TF) spectrums which are processed by SET are fed into the convolutional neural networks (CNN) classifier. The accuracy of recognize ictal and preictal signals reaches 99.7% and 93.7% respectively. To summarize, our results based on nonlinear method provide new research ideas for seizures detection and prediction.
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The DNA-encoded library (DEL) is a robust tool for chemical biology and drug discovery. In this study, we developed a DNA-compatible light-promoted reaction that is highly efficient and plate-compatible for DEL construction based on the formation of the indazolone scaffold. Employing this high-efficiency approach, we constructed a DEL featuring an indazolone core, which enabled the identification of a novel series of ligands specifically targeting E1A-binding protein (p300) after DEL selection. Taken together, our findings underscore the feasibility of light-promoted reactions in DEL synthesis and unveil promising avenues for developing p300-targeting inhibitors.
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In recent years, graphitic carbon nitride (g-C3N4) has attracted considerable attention because it includes earth-abundant carbon and nitrogen elements and exhibits good chemical and thermal stability owing to the strong covalent interaction in its conjugated layer structure. However, bulk g-C3N4 has some disadvantages of low specific surface area, poor light absorption, rapid recombination of photogenerated charge carriers, and insufficient active sites, which hinder its practical applications. In this study, we design and synthesize potassium single-atom (K SAs)-doped g-C3N4 porous nanosheets (CM-KX, where X represents the mass of KHP added) via supramolecular self-assembling and chemical cross-linking copolymerization strategies. The results show that the utilization of supramolecules as precursors can produce g-C3N4 nanosheets with reduced thickness, increased surface area, and abundant mesopores. In addition, the intercalation of K atoms within the g-C3N4 nitrogen pots through the formation of K-N bonds results in the reduction of the band gap and expansion of the visible-light absorption range. The optimized K-doped CM-K12 nanosheets achieve a specific surface area of 127 m2 g-1, which is 11.4 times larger than that of the pristine g-C3N4 nanosheets. Furthermore, the optimal CM-K12 sample exhibits the maximum H2 production rate of 127.78 µmol h-1 under visible light (λ ≥ 420 nm), which is nearly 23 times higher than that of bare g-C3N4. This significant improvement of photocatalytic activity is attributed to the synergistic effects of the mesoporous structure and K SAs doping, which effectively increase the specific surface area, improve the visible-light absorption capacity, and facilitate the separation and transfer of photogenerated electron-hole pairs. Besides, the optimal sample shows good chemical stability for 20 h in the recycling experiments. Density functional theory calculations confirm that the introduction of K SAs significantly boosts the adsorption energy for water and decreases the activation energy barrier for the reduction of water to hydrogen.
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Hepatocellular carcinoma is one of the leading causes of cancer-related mortality globally. The emergence of immunotherapy has been shown to be a promising therapeutic approach for hepatocellular carcinoma in recent years. It has been well known that T cell plays a key role in current immunotherapy. However, sustained exposure to antigenic stimulation within the tumor microenvironment may lead to T cell exhaustion, which may cause treatment ineffectiveness. Therefore, reversing T cell exhaustion has been an important issue for the clinical application of immunotherapy, and a comprehensive understanding of the intricacies surrounding T cell exhaustion and its underlying mechanisms is imperative for devising strategies to overcome the T cell exhaustion during treatment. In this review, we summarized the reported drivers of T cell exhaustion in hepatocellular carcinoma and delineate potential ways to reverse it. Additionally, we discussed the interplay among metabolic plasticity, epigenetic regulation, and transcriptional factors in exhausted T cells in hepatocellular carcinoma, and their implication for future clinical applications.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Linfócitos T , Microambiente Tumoral , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Animais , Linfócitos T/imunologia , Microambiente Tumoral/imunologia , Epigênese Genética , Imunoterapia , Exaustão das Células TRESUMO
DNA-encoded chemical library (DEL) has been extensively used for lead compound discovery for decades in academia and industry. Incorporating an electrophile warhead into DNA-encoded compounds recently permitted the discovery of covalent ligands that selectively react with a particular cysteine residue. However, noncysteine residues remain underexplored as modification sites of covalent DELs. Herein, we report the design and utility of tyrosine-targeting DELs of 67 million compounds. Proteome-wide reactivity analysis of tyrosine-reactive sulfonyl fluoride (SF) covalent probes suggested three enzymes (phosphoglycerate mutase 1, glutathione s-transferase 1, and dipeptidyl peptidase 3) as models of tyrosine-targetable proteins. Enrichment with SF-functionalized DELs led to the identification of a series of tyrosine-targeting covalent inhibitors of the model enzymes. In-depth mechanistic investigation revealed their novel modes of action and reactive ligand-accessible hotspots of the enzymes. Our strategy of combining activity-based proteome profiling and covalent DEL enrichment (ABPP-CoDEL), which generated selective covalent binders against a variety of target proteins, illustrates the potential use of this methodology in further covalent drug discovery.
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Proteoma , Tirosina , Proteoma/química , Descoberta de Drogas/métodos , Bibliotecas de Moléculas Pequenas/farmacologia , Ligantes , DNARESUMO
Carbohydrates are an important class of naturally active products and play vital roles in regulating various physiological activities. To meet the demand for carbohydrate-based libraries used for the identification of potential drug candidates for pharmaceutical-related targets, we developed a set of on-DNA protocols to construct the DNA-encoded glycoconjugates, including Seyferth-Gilbert homologation, anomeric azidation, and CuAAC cyclization. These on-DNA chemistries enable the generation and modification of DNA-linked glycosyl compounds with good conversions and broad substrate scope. Finally, three DNA-linked glycoconjugate libraries were successfully generated to demonstrate their applicability and feasibility in library preparation.
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Obesity increases the severity of airway hyperresponsiveness (AHR) in individuals with asthma, but the mechanism is not well elucidated. G-protein coupled receptor 40 (GPR40) has been found to induce airway smooth muscle contraction after activated by long-chain fatty acids (LC-FFAs), suggesting a close correlation between GPR40 and AHR in obese. In this study, C57BL/6 mice were fed a high-fat diet (HFD) to induce obesity with or without ovalbumin (OVA) sensitization, the regulatory effects of GPR40 on AHR, inflammatory cells infiltration, and the expression of Th1/Th2 cytokines were evaluated by using a small-molecule antagonist of GPR40, DC260126. We found that the free fatty acids (FFAs) level and GPR40 expression were greatly elevated in the pulmonary tissues of obese asthmatic mice. DC260126 greatly reduced methacholine-induced AHR, ameliorated pulmonary pathological changes and decreased inflammatory cell infiltration in the airways in obese asthma. In addition, DC260126 could down-regulate the levels of Th2 cytokines (IL-4, IL-5, and IL-13) and pro-inflammatory cytokines (IL-1ß, TNF-α), but elevated Th1 cytokine (IFN-γ) expression. In vitro, DC260126 could remarkedly reduce oleic acid (OA)-induced cell proliferation and migration in HASM cells. Mechanistically, the effects that DC260126 alleviated obese asthma was correlated with the down-regulation of GTP-RhoA and Rho-associated coiled-coil-forming protein kinase 1 (ROCK1). Herein, we proved that targeting of GPR40 with its antagonist helped to mitigate multiple parameters of obese asthma effectively.
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Asma , Receptores Acoplados a Proteínas G , Hipersensibilidade Respiratória , Animais , Camundongos , Asma/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Pulmão/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/metabolismo , Ovalbumina , Receptores Acoplados a Proteínas G/metabolismo , Hipersensibilidade Respiratória/metabolismo , Transdução de SinaisRESUMO
The photo-responsive adsorption has emerged as a vibrant area, but its current methodology is limited by the well-defined photochromic units and their molecular deformation driven by photo-stimuli. Herein, a methodology of nondeforming photo-responsiveness is successfully exploited. With the exploiting agent of Cu-TCPP framework assembled on the graphite and strongly interacted with it, the sorbent generates two kinds of adsorption sites, over which the electron density distribution of the graphite layer can be modulated at the c-axis direction, which can further evolve due to photo-stimulated excited states. The excited states are stable enough to meet the timescale of microscopic adsorption equilibrium. Independent of the ultra-low specific surface area of the sorbent (20â m2 g-1 ), the CO adsorption capability can be improved from 0.50â mmol g-1 at the ground state to 1.24â mmol g-1 (0 °C, 1â bar) with the visible light radiation, rather than the photothermal desorption.
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The DNA-encoded compound library (DEL) technology has accelerated the target hits discovery in new drug development. While affinity-based DEL selection can distinguish high-affinity ligands, moderate-affinity ligands are also potential drug candidates with further modifications. Herein, we designed a photo-cross-linking selection method for DELs with double-stranded DNA (dsDELs) to screen moderate-affinity ligands. We constructed two photo-cross-linking libraries with linkers of different lengths that connect a diazirine group to the DNA encoded compound. The diazirine group can be activated by UV irradiation and thus bond with the target protein in a reachable distance. In the model selection, the feasibility of the photo-cross-linking screening system was verified by qPCR and NGS technology. Both high-affinity and moderate-affinity ligands were successfully selected from the libraries.
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Descoberta de Drogas , Bibliotecas de Moléculas Pequenas , Ligantes , Bibliotecas de Moléculas Pequenas/química , Descoberta de Drogas/métodos , Diazometano , DNA/químicaRESUMO
Macrocyclic peptides are an important class of therapeutic agents for the biological targets that are difficult to modulate by small-molecule compounds. Meanwhile, DNA-encoded library technology (DELT) provides a powerful platform for hits discovery. The unity of both fields has proven highly productive in finding cyclic peptide hits against diverse pharmaceutical proteins. Many researchers have extended the chemical toolbox for constructing head-to-tail macrocyclic DNA-encoded libraries with various ring sizes. However, the linear peptides of different lengths necessitate tuning the distance between closing sites and DNA-linked sites to perform the macrocyclization process, presumably due to the constrained conformation of linear precursors. To tackle this issue and streamline the synthetic workflow, we report a two-directional synthesis strategy. This method starts from a trifunctional reagent and prepares DNA-linked macrocyclic peptides of ring size between 15 (5-mer) and 24 (8-mer) via amide bond formation reaction, a common method to create macrocyclic peptides.
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Peptídeos Cíclicos , Peptídeos , Ciclização , DNA/química , Biblioteca Gênica , Biblioteca de Peptídeos , Peptídeos/química , Peptídeos Cíclicos/químicaRESUMO
A group of highly efficient and divergent transformations for constructing multiple DNA-linked chemotypes based on a piperidone core were successfully developed. We reported the first procedure for the synthesis of a DNA-conjugated piperidine intermediate under basic conditions. Subsequently, this substructure was subjected to additional reactions to generate several privileged scaffolds, including 4-aminopiperidine, fused [1,2,4]triazolo[1,5-a]pyrimidine, and a quinoline derivative. These transformations paved the way for constructing focused scaffold-based DNA-encoded libraries with druglike properties.
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Piperidonas , DNA/química , Piperidonas/químicaRESUMO
BACKGROUND: Fear of falling and environmental barriers in the home are two major factors that cause the incidence of falling. Poor visibility at night is one of the key environmental barriers that contribute to falls among older adult residents. Ensuring their visual perception of the surroundings, therefore, becomes vital to prevent falling injuries. However, there are limited works in the literature investigating the impact of the visibility of the target on older adults' walking destinations and how that impact differs across them with different levels of fear of falling. OBJECTIVE: The purpose of the study was to examine the effects of target salience on older adults' walking performance and investigate whether older adults with varying levels of fear of falling behave differently. METHODS: The salient target was constructed with LED strips around the destination of walking. Fifteen older adults (aged 75 years old and above), seven with low fear of falling and eight with high fear of falling, volunteered for the study. Participants walked from the designated origin (i.e., near their beds) to the destination (i.e., near the bathroom entrance), with the target turned on or off around the destination of the walking trials. Spatiotemporal gait variables and lower-body kinematics were recorded by inertial sensors and compared by using analysis of variance methods. RESULTS: Data from inertial sensors showed that a more salient target at the destination increased older adults' gait speed and improved their walking stability. These changes were accompanied by less hip flexion at heel strikes and toe offs during walking. In addition, older adults with low fear of falling showed more substantial lower-body posture adjustments with the salient target presented in the environment. CONCLUSIONS: Older adults with a low fear of falling can potentially benefit from a more salient target at their walking destination, whereas those with a high fear of falling were advised to implement a more straightforward falling intervention in their living areas.
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Acidentes por Quedas , Medo , Humanos , Idoso , Acidentes por Quedas/prevenção & controle , Marcha , Caminhada , Velocidade de CaminhadaRESUMO
DNA-encoded library (DEL) technology provided a powerful screening platform for identifying potential bioactive small molecules with high affinity to biologically interesting targets. Essential to a successful DEL campaign are the drug-like small molecular moieties of DNA-encoded libraries with expanded chemical space. Our laboratory has been working on developing and producing novel DNA-encoded libraries that complement current reported DELs. Herein, we demonstrated a general set of DNA-compatible reactions that enable the preparation of pyrrole-based DNA-encoded libraries in which the DNA tags are linked to the N position of the pyrrole central core. Further diversification could be rapidly incorporated into the pyrrole scaffold by robust iodination and Suzuki coupling reactions.
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Bibliotecas de Moléculas PequenasRESUMO
Enzymatic catalysis is a highly attractive approach to the DNA encoded library technology (DEL) that has not been widely explored. In this paper, we report an l-threonine aldolase (l-TA)-catalyzed on-DNA aldol reaction to form ß-hydroxy-α-amino acids, and its diastereoselectivity determination. l-TAs from three species show good on-DNA aldehyde scope and complementary stereoselectivity. The formed aldol product can be further diversified via various reactions, which demonstrates the utility of this reaction in DEL.
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Glicina Hidroximetiltransferase , Aldeídos , Catálise , Especificidade por SubstratoRESUMO
We described a mode of catalytic activation that accomplished the α-alkylation of N-Boc saturated heterocycles with DNA-linked acrylamide via photoredox-mediated hydrogen atom transfer (HAT) catalysis. This C(sp3)-C(sp3) bond formation reaction tolerated five-, six- and seven-membered cyclic substrates, substantially streamline synthetic efforts to functionalize the α-position of heterocycles with native CH functional handle. This photoredox catalyzed CH functionalization proceeded in mild DNA-compatible condition, and suited for the construction of DNA-encoded libraries.
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DNA/química , Hidrogênio/química , Acrilamida/química , Catálise , Estrutura Molecular , Oxirredução , Processos FotoquímicosRESUMO
Gut microbiome has received significant attention for its influences on a variety of host functions, especially immune modulation. With the next-generation sequencing methodologies, more knowledge is gathered about gut microbiome and its irreplaceable role in keeping the balance between human health and diseases is figured out. Immune checkpoint inhibitors (ICIs) are one of the most innovational cancer immunotherapies across cancer types and significantly expand the therapeutic options of cancer patients. However, a proportion of patients show no effective responses or develop immune-related adverse events when responses do occur. More important, it is demonstrated that the therapeutic response or treatment-limiting toxicity of cancer immunotherapy can be ameliorated or diminished by gut microbiome modulation. In this review, we first introduce the relationship between gut microbiome and cancer immunotherapy. And then, we expound the impact of gut microbiome on efficacy and toxicity of cancer immunotherapy. Further, we review approaches to manipulating gut microbiome to regulate response to ICIs. Finally, we discuss the current challenges and propose future directions to improve cancer immunotherapy via gut microbiome manipulation.
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Microbioma Gastrointestinal , Imunoterapia/métodos , Neoplasias/terapia , Animais , Antineoplásicos/uso terapêutico , Bactérias/classificação , Bactérias/efeitos dos fármacos , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias/microbiologiaRESUMO
A mild reaction for DNA-compatible, palladium promoted Suzuki-Miyaura cross-coupling reaction of potassium Boc-protected aminomethyltrifluoroborate with DNA-conjugated aryl bromides has been developed efficiently. This novel DNA encoded chemistry reaction proceeded well with a wide range of functional group tolerance, including aryl bromides and heteroaryl bromides. Further, the utility our DNA conjugated aminomethylated arene products is demonstrated by reaction with various types of reagents (including amide formation with carboxylic acids, alkylation with aldehydes, and carbamoylation with amines) as would be desired for the production of a DNA encoded library.
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Boratos/química , Brometos/química , DNA/química , Hidrocarbonetos Aromáticos/química , Aminação , Boratos/síntese química , Brometos/síntese química , Catálise , Técnicas de Química Combinatória , DNA/síntese química , Halogenação , Hidrocarbonetos Aromáticos/síntese química , Metilação , Paládio/química , Potássio/química , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/químicaRESUMO
BACKGROUND: Several recent studies published have suggested that T cell exhaustion exists both in chronic infection and cancer. However, to date, few studies have investigated their differences. Here we designed this study to explore the genetic and phenotypic difference in CD8+ T cell exhaustion between chronic hepatitis B (CHB) and hepatocellular carcinoma (HCC). METHODS: In this study, we assayed the phenotypes and functional states of CD8+ T cells separating from human CHB tissues and HCC tissues, and re-analyse the single-cell sequencing data (GSE98638) published previously. Clustering analysis of genes was performed using the T cell exhaustion gene modules (modules 1-4) proposed by Speiseret al. RESULTS: CD8+ T cells from liver tissues of both CHB and HCC showed high levels of exhaustion markers, DOI: programmed cell death-1 (PD-1), T-cell immunoglobulin and mucin-domain containing-3 (TIM-3), cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), and lymphocyte-activation gene 3 (LAG-3), decreased proliferation (Ki67) and cell activity (CD69), and reduced production of effector cytokines (interferon-γ, interleukin-2 and tumour necrosis factor-α). Compared with CD8+ T cells from CHB tissues, those from HCC tissue showed higher expression levels of exhaustion markers, lower levels of proliferation, cell activity and the production of effector cytokines. Cluster analysis showed that exhaustion associated genes in CHB and HCC are inclined to distribute into modules 3 while those isolated from HCC into modules 1 and 2. CONCLUSIONS: CD8+ T cell exhaustion existed both in CHB and HCC, but the phenotypes, functional states and underlying mechanisms are somewhat different between the two.
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Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Carcinoma Hepatocelular/etiologia , Hepatite B Crônica/complicações , Neoplasias Hepáticas/etiologia , Biomarcadores Tumorais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Feminino , Variação Genética , Humanos , Imunofenotipagem , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Contagem de Linfócitos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Masculino , FenótipoRESUMO
BACKGROUND: Previous studies suggested that diverse cells in cancer microenvironment can interact with CD8+ T cells via exosomes. We designed this study to explore the potential interaction between exhausted CD8+ T cells and normal CD8+ T cells via exosome. METHODS: Fluorescence activated cell sorting was used to get PD1+TIM3+/PD1-TIM3-CD8+ T cells. Exosomes from the cell culture medium were collected by ultracentrifugation. Microarrays were performed to analyse the lncRNA expression profile in exosomes. RESULTS: Functional exhausted CD8+ T cells could secrete vast exosomes, which can be uptake by normal CD8+ T cells, and impaired their proliferation (Ki67), cell activity (CD69) and the production of cytokines such as interferon-γ and interleukin-2. Microarray detection identified 257 candidate lncRNAs differently expressed in exosomes derived from exhausted CD8+ T cells and non-exhausted CD8+ T cells. Functional enrichment analysis indicated that these lncRNAs actively participated in the regulation of diverse process of CD8+ T cell activity, like metabolism, gene expression, biosynthetic process and so forth. CONCLUSIONS: The exosomes derived from exhausted CD8+ T cells could be uptake by non-exhausted CD8+ T cells and subsequently impaired the function of receipt cells. Exosomes secreted from exhausted CD8+ T cells have distinct lncRNA expression profiles which are significantly different from those in exosomes secreted by non-exhausted CD8+ T cells.
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Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Exossomos/metabolismo , Neoplasias/etiologia , Neoplasias/metabolismo , Biomarcadores , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Imunofenotipagem , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/patologia , MicroRNAs/genética , Neoplasias/patologia , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Microambiente Tumoral/genética , Microambiente Tumoral/imunologiaRESUMO
Immunotherapy has emerged as one of the most promising therapeutic strategies in cancer. The clustered regularly interspaced short palindromic repeat (CRISPR)-associated protein 9 (CRISPR-Cas9) system, as an RNA-guided genome editing technology, is triggering a revolutionary change in cancer immunotherapy. With its versatility and ease of use, CRISPR-Cas9 can be implemented to fuel the production of therapeutic immune cells, such as construction of chimeric antigen receptor T (CAR-T) cells and programmed cell death protein 1 knockout. Therefore, CRISPR-Cas9 technology holds great promise in cancer immunotherapy. In this review, we will introduce the origin, development and mechanism of CRISPR-Cas9. Also, we will focus on its various applications in cancer immunotherapy, especially CAR-T cell-based immunotherapy, and discuss the potential challenges it faces.