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Natural killer (NK) cells are unique from other immune cells in that they can rapidly kill multiple neighboring cells without the need for antigenic pre-sensitization once the cells display surface markers associated with oncogenic transformation. Given the dynamic role of NK cells in tumor surveillance, NK cell-based immunotherapy is rapidly becoming a "new force" in tumor immunotherapy. However, challenges remain in the use of NK cell immunotherapy in the treatment of solid tumors. Many metabolic features of the tumor microenvironment (TME) of solid tumors, including oxygen and nutrient (e.g., glucose, amino acids) deprivation, accumulation of specific metabolites (e.g., lactate, adenosine), and limited availability of signaling molecules that allow for metabolic reorganization, multifactorial shaping of the immune-suppressing TME impairs tumor-infiltrating NK cell function. This becomes a key barrier limiting the success of NK cell immunotherapy in solid tumors. Restoration of endogenous NK cells in the TME or overt transfer of functionally improved NK cells holds great promise in cancer therapy. In this paper, we summarize the metabolic biology of NK cells, discuss the effects of TME on NK cell metabolism and effector functions, and review emerging strategies for targeting metabolism-improved NK cell immunotherapy in the TME to circumvent these barriers to achieve superior efficacy of NK cell immunotherapy.
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Reprogramación Metabólica , Neoplasias , Humanos , Microambiente Tumoral , Células Asesinas Naturales , Ácido Láctico , Neoplasias/terapiaRESUMEN
BACKGROUND: Previous studies on whole grain consumption had inconsistent findings and lacked quantitative assessments of evidence quality. Therefore, we aimed to summarize updated findings using the Burden of Proof analysis (BPRF) to investigate the relationship of whole grain consumption on type 2 diabetes (T2D), colorectal cancer (CRC), stroke, and ischemic heart disease (IHD). METHODS: We conducted a literature search in the Medline and Web of Science up to June 12, 2023, to identify related cohort studies and systematic reviews. The mean RR (relative risk) curve and uncertainty intervals (UIs), BPRF function, risk-outcome score (ROS), and the theoretical minimum risk exposure level (TMREL) were estimated to evaluate the level of four risk-outcome pairs. RESULTS: In total, 27 prospective cohorts were included in our analysis. Consuming whole grain at the range of TMREL (118.5-148.1 g per day) was associated with lower risks: T2D (declined by 37.3%, 95% UI: 5.8 to 59.5), CRC (declined by 17.3%, 6.5 to 27.7), stroke (declined by 21.8%, 7.3 to 35.1), and IHD (declined by 36.9%, 7.1 to 58.0). For all outcomes except stroke, we observed a non-linear, monotonic decrease as whole grain consumption increased; For stroke, it followed a J-shaped curve (the greatest decline in the risk of stroke at consuming 100 g whole grain for a day). The relationships between whole grain consumption and four diseases are all two-star pairs (ROS: 0.087, 0.068, 0.062, 0.095 for T2D, CRC, stroke, and IHD, respectively). CONCLUSION: Consuming 100 g of whole grains per day offers broad protective benefits. However, exceeding this threshold may diminish the protective effects against stroke. Our findings endorse replacing refined grains with whole grains as the main source of daily carbohydrates. REGISTRY AND REGISTRY NUMBER FOR SYSTEMATIC REVIEWS OR META-ANALYSES: We have registered our research in PROSPERO, and the identifier of our meta-analyses is CRD42023447345.
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Enfermedades Cardiovasculares , Neoplasias Colorrectales , Diabetes Mellitus Tipo 2 , Granos Enteros , Humanos , Diabetes Mellitus Tipo 2/epidemiología , Neoplasias Colorrectales/epidemiología , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Dieta/métodos , Dieta/estadística & datos numéricos , Estudios Prospectivos , Factores de RiesgoRESUMEN
Intrinsic or acquired drug resistance of tumor cells is the main cause of tumor chemotherapy failure and tumor-related death. Bufalin (BF) is the main active monomer component extracted from the Traditional Chinese Medicine Toad venom (secretions of glands behind the ears and epidermis of bufo gargarizans and Bufo Melanostictus Schneider). It is a cardiotonic steroid with broad-spectrum anti-cancer effects and has been widely used against various malignant tumors in clinical practice. Pharmacological studies also found that BF has the effect of reversing drug resistance, which provides a new perspective for the application of Traditional Chinese Medicine as a chemosensitizer in cancer therapy. This article provides an extensive search and summary of published research on mitigating drug resistance to BF and reviews its potential mechanisms.
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Bufanólidos , Neoplasias , Humanos , Biofarmacia , Bufanólidos/farmacología , Bufanólidos/uso terapéutico , Neoplasias/tratamiento farmacológico , Resistencia a MedicamentosRESUMEN
OBJECTIVES: This study aimed to develop and validate a predicting model for the histologic classification of solid lung lesions based on preoperative contrast-enhanced CT. METHODS: A primary dataset of 1012 patients from Tianjin Medical University Cancer Institute and Hospital (TMUCIH) was randomly divided into a development cohort (708) and an internal validation cohort (304). Patients from the Second Hospital of Shanxi Medical University (SHSMU) were set as an external validation cohort (212). Two clinical factors (age, gender) and twenty-one characteristics on contrast-enhanced CT were used to construct a multinomial multivariable logistic regression model for the classification of seven common histologic types of solid lung lesions. The area under the receiver operating characteristic curve was used to assess the diagnostic performance of the model in the development and validation cohorts, separately. RESULTS: Multivariable analysis showed that two clinical factors and twenty-one characteristics on contrast-enhanced CT were predictive in lung lesion histologic classification. The mean AUC of the proposed model for histologic classification was 0.95, 0.94, and 0.92 in the development, internal validation, and external validation cohort, respectively. When determining the malignancy of lung lesions based on histologic types, the mean AUC of the model was 0.88, 0.86, and 0.90 in three cohorts. CONCLUSIONS: We demonstrated that by utilizing both clinical and CT characteristics on contrast-enhanced CT images, the proposed model could not only effectively stratify histologic types of solid lung lesions, but also enabled accurate assessment of lung lesion malignancy. Such a model has the potential to avoid unnecessary surgery for patients and to guide clinical decision-making for preoperative treatment. KEY POINTS: ⢠Clinical and CT characteristics on contrast-enhanced CT could be used to differentiate histologic types of solid lung lesions. ⢠Predicting models using preoperative contrast-enhanced CT could accurately assessment of tumor malignancy based on predicted histologic types.
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Neoplasias Pulmonares , Humanos , Estudios Retrospectivos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Pulmón/patología , Curva ROC , Tomografía Computarizada por Rayos X/métodosRESUMEN
During the translocation step of prokaryotic protein synthesis, elongation factor G (EF-G), a guanosine triphosphatase (GTPase), binds to the ribosomal PRE-translocation (PRE) complex and facilitates movement of transfer RNAs (tRNAs) and messenger RNA (mRNA) by one codon. Energy liberated by EF-G's GTPase activity is necessary for EF-G to catalyze rapid and precise translocation. Whether this energy is used mainly to drive movements of the tRNAs and mRNA or to foster EF-G dissociation from the ribosome after translocation has been a long-lasting debate. Free EF-G, not bound to the ribosome, adopts quite different structures in its GTP and GDP forms. Structures of EF-G on the ribosome have been visualized at various intermediate steps along the translocation pathway, using antibiotics and nonhydolyzable GTP analogs to block translocation and to prolong the dwell time of EF-G on the ribosome. However, the structural dynamics of EF-G bound to the ribosome have not yet been described during normal, uninhibited translocation. Here, we report the rotational motions of EF-G domains during normal translocation detected by single-molecule polarized total internal reflection fluorescence (polTIRF) microscopy. Our study shows that EF-G has a small (â¼10°) global rotational motion relative to the ribosome after GTP hydrolysis that exerts a force to unlock the ribosome. This is followed by a larger rotation within domain III of EF-G before its dissociation from the ribosome.
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Guanosina Trifosfato/metabolismo , Factor G de Elongación Peptídica/metabolismo , Ribosomas/metabolismo , Secuencia de Aminoácidos , Datos de Secuencia Molecular , Sistemas de Translocación de ProteínasRESUMEN
In this study, taking Cistanche deserticola in Xinjiang as the experimental material, the optimal process for extracting polysaccharides from C. deserticola with water extraction was studied by using single factor and orthogonal experiment. Its effects on protein removal and polysaccharides retaining were investigated by using Sevag, enzymatic method or combination of these two methods, so as to determine the optimal method for protein removal from polysaccharides of C. deserticola; the decolorization and purification methods such as macroporous resin of AB-8 and activated Carbon were used to determine the optimal process. The results showed that the extraction rate of polysaccharides from C. deserticola was 18.40% during the optimal process of the water extraction as follows: extraction temperature 75 â, extraction time 165 min and solid-liquid ratio 1â¶55. The protein removal rate can reach 31.40% and polysaccharide retention rate can reach 96.00% under the optimal protein removal process: temperature 50 â, time 2 h, and papain dosage 0.2%. The decolorization rate of activated Carbon and macroporous resin called AB-8 was 80.37% and 86.43%, and the recovery rate of polysaccharides was 77.05% and 91.93%, respectively, suggesting that macroporous resin was more suitable for decoloration. Macroporous resin named AB-8 increased the purity of the polysaccharide crude extract from 67.70% to 84.80% under the following conditions: concentration of the sample 4 g·L~(-1), concentration of the eluent 60% ethanol, and the flow rate 1 mL·min~(-1), showing significant purification effect.
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Cistanche/química , Extractos Vegetales/química , Polisacáridos/aislamiento & purificación , Temperatura , AguaRESUMEN
Standard plate count (SPC) has been recognized as the golden standard for the quantification of viable bacteria. However, SPC usually takes one to several days to grow individual cells into a visible colony, which greatly hampers its application in rapid bacteria enumeration. Here we present a microdroplet turbidity imaging based digital standard plate count (dSPC) method to overcome this hurdle. Instead of cultivating on agar plates, bacteria are encapsulated in monodisperse microdroplets for single-cell cultivation. Proliferation of the encapsulated bacterial cell produced a detectable change in microdroplet turbidity, which allowed, after just a few bacterial doubling cycles (i.e., a few hours), enumeration of viable bacteria by visible-light imaging. Furthermore, a dSPC platform integrating a power-free droplet generator with smartphone-based turbidity imaging was established. As proof-of-concept demonstrations, a series of Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Bacillus subtilis) samples were quantified via the smartphone dSPC accurately within 6 hours, representing a detection sensitivity of 100 CFU ml-1 and at least 3 times faster. In addition, Enterobacter sakazakii (E. sakazakii) in infant milk powder as a real sample was enumerated within 6 hours, in contrast to the 24 hours needed in traditional SPC. Results with high accuracy and reproducibility were achieved, with no difference in counts found between dSPC and SPC. By enabling label-free, rapid, portable and low-cost enumeration and cultivation of viable bacteria onsite, smartphone dSPC forms the basis for a temporally and geographically trackable network for surveying live microbes globally where every citizen with a cellphone can contribute anytime and anywhere.
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Bacterias/aislamiento & purificación , Recuento de Colonia Microbiana/métodos , Teléfono Inteligente , Bacillus subtilis/aislamiento & purificación , Escherichia coli/aislamiento & purificación , Reproducibilidad de los Resultados , Análisis de la Célula IndividualRESUMEN
BACKGROUND/AIMS: Colorectal cancer (CRC) is the third leading cause of cancer-related death worldwide because the survival rate remains low. Cell division cycle 5-like (CDC5L) is highly expressed in some cancer cells, but the mechanism requires clarification. Human telomerase reverse transcriptase (hTERT) plays important roles in CRC. METHODS: This study aimed to identify a link between CDC5L and hTERT and to determine their effects on the signaling pathways, migration and prognosis of CRC cells. We first treated LoVo cells with biotin-labeled hTERT and identified CDC5L. Then, pulldown and ChIP assays were used to verify whether CDC5L was a promoter of hTERT. The roles of CDC5L and hTERT in cell growth and migration were studied using siRNA in vivo and in vitro. 130 human CRC specimens were analyzed using immunohistochemistry. Western blot and wound scratch analyses were used to determine the signaling pathway for CDC5L-mediated activation of CRC growth and migration. RESULTS: We identified CDC5L as a new hTERT promoter-binding protein. Clinically, CDC5L and hTERT expression levels were key factors in the prognosis of CRC patients. CDC5L knockdown inhibited tumor growth by down-regulating hTERT expression, and CDC5L was shown to be a transcriptional activator of hTERT in a luciferase reporter assay. CONCLUSION: Altogether, the above results demonstrated that CDC5L was positively correlated with hTERT as a key promoter of CRC cells. To some extent, our findings suggest that CDC5L may serve as a novel therapeutic target for human colorectal cancer.
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Proteínas de Ciclo Celular/metabolismo , Neoplasias Colorrectales/fisiopatología , Regulación Neoplásica de la Expresión Génica/genética , Proteínas de Unión al ARN/metabolismo , Telomerasa/genética , Telomerasa/metabolismo , Anciano , Animales , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular/genética , Supervivencia Celular , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/mortalidad , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Ratones , Persona de Mediana Edad , Estadificación de Neoplasias , Regiones Promotoras Genéticas , Interferencia de ARN , Proteínas de Unión al ARN/antagonistas & inhibidores , Proteínas de Unión al ARN/genética , Activación Transcripcional , Trasplante HeterólogoRESUMEN
BACKGROUND/AIMS: Bufalin can induce apoptosis in certain human cancer cell lines, but bufalin has not yet been thoroughly evaluated in colorectal cancer cells. Cleavage and polyadenylation specific factor 4 (CPSF4) and human telomerase reverse transcriptase (hTERT) play important roles in colorectal cancer growth. The aim of this study was to investigate the roles and interactions of bufalin, CPSF4 and hTERT and the effects of bufalin in human colorectal cancer. METHODS: We treated LoVo and SW620 cells with bufalin to investigate the effect of bufalin on proliferation, apoptosis and migration. We verified the relationship between CPSF4 and hTERT using pulldown assays, luciferase reporter assays and chromatin immunoprecipitation (ChIP) assays. RESULTS: Bufalin inhibited the proliferation and migration of and induced apoptosis in LoVo and SW620 cells. We identified CPSF4 as an hTERT promoter-binding protein in colorectal cancer cells. CONCLUSION: Our study identified bufalin as a potential small molecule inhibitor for cancer therapy.
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Bufanólidos/farmacología , Factor de Especificidad de Desdoblamiento y Poliadenilación/metabolismo , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Telomerasa/metabolismo , Apoptosis/efectos de los fármacos , Bufanólidos/química , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Humanos , Regiones Promotoras Genéticas , Unión Proteica/efectos de los fármacos , Telomerasa/genéticaRESUMEN
We present a flexible, real-time-coupled transcription-translation assay that involves the continuous monitoring of fluorescent Emerald GFP formation. Along with numerical simulation of a reaction kinetics model, the assay permits quantitative estimation of the effects on full-length protein synthesis of various additions, subtractions or substitutions to the protein synthesis machinery. Since the assay uses continuous fluorescence monitoring, it is much simpler and more rapid than other assays of protein synthesis and is compatible with high-throughput formats. Straightforward alterations of the assay permit determination of (i) the fraction of ribosomes in a cell-free protein synthesis kit that is active in full-length protein synthesis and (ii) the relative activities in supporting protein synthesis of modified (e.g. mutated, fluorescent-labeled) exogenous components (ribosomes, amino acid-specific tRNAs) that replace the corresponding endogenous components. Ribosomes containing fluorescent-labeled L11 and tRNAs labeled with fluorophores in the D-loop retain substantial activity. In the latter case, the extent of activity loss correlates with a combination of steric bulk and hydrophobicity of the fluorophore.
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Fluorometría/métodos , Biosíntesis de Proteínas , Sistema Libre de Células , Proteínas Fluorescentes Verdes/biosíntesis , Sustancias Luminiscentes/análisis , Fenilalanina/metabolismo , Aminoacil-ARN de Transferencia/metabolismo , ARN de Transferencia de Fenilalanina/metabolismo , Ribosomas/metabolismo , Transcripción GenéticaRESUMEN
As the most common cause of dementia, Alzheimer's disease (AD) is characterized by neurodegeneration and synaptic loss with an increasing prevalence in the elderly. Increased inflammatory responses triggers brain cells to produce pro-inflammatory cytokines and accelerates the Aß accumulation, tau protein hyper-phosphorylation leading to neurodegeneration. Therefore, in this paper, we discuss the current understanding of how inflammation affects brain activity to induce AD pathology, the inflammatory biomarkers and possible therapies that combat inflammation for AD.
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Liver cancer is the 4th most lethal form of cancer with a poor prognosis for patients worldwide. Dysregulation of lipid metabolism is related to FA oxidation alternation which can be modified by peroxisome proliferator-activated receptor-α (PPARα). Therefore, it is important to identify the lipid metabolism-related genes regulated by PPARα in liver cancer. Hub genes related to the lipid metabolism pathway of HCC samples treated with PPARα agonist (WY-14,643) were identified through a weighted gene co-expression network analysis (WGCNA). Gene expression and clinical information were obtained from the Gene Expression Omnibus (GEO) database. The network of top main hub genes was visualized by the Cytoscape software using MCODE and CytoHubba plugins. Finally, the expression and clinical association of each hub gene were evaluated using enrichment analysis, TCGA data, GEPIA, GSCA, and q-PCR. Based on our results, the top 5 co-expressed genes including (CPT2, ACSL1, ACSL3, ACOX1, and SLC27A2) were selected as the main hub genes participating in fatty acid metabolism, fatty acid beta-oxidation, and PPAR signaling pathway. All association of higher ACSL3 expression with lower outcomes and survival rates was detected in HCC patients. Therefore, lipid metabolism-related Hub genes regulated by PPARα are potential biomarkers, and they may offer a therapeutical foundation for targeted therapy directed against the HCC antitumor strategy.
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Carcinoma Hepatocelular , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Metabolismo de los Lípidos , Neoplasias Hepáticas , PPAR alfa , Humanos , PPAR alfa/agonistas , PPAR alfa/genética , PPAR alfa/metabolismo , Metabolismo de los Lípidos/genética , Metabolismo de los Lípidos/efectos de los fármacos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Coenzima A Ligasas/genética , Coenzima A Ligasas/metabolismo , Perfilación de la Expresión Génica/métodos , Pronóstico , Biología Computacional/métodosRESUMEN
Early diagnosis of lung cancer (LC) can significantly reduce its mortality rate. Considering the limitations of the high false positive rate and reliance on radiologists' experience in computed tomography (CT)-based diagnosis, a multi-modal early LC screening model that combines radiology with other non-invasive, rapid detection methods is warranted. A high-resolution, multi-modal, and low-differentiation LC screening strategy named ensemble text and breath analysis (ETBA) is proposed that ensembles radiology report text analysis and breath analysis. In total, 231 samples (140 LC patients and 91 benign lesions [BL] patients) were screened using proton transfer reaction-time of flight-mass spectrometry and CT screening. Participants were randomly assigned to a training set and a validation set (4:1) with stratification. The report section of the radiology reports was used to train a text analysis (TA) model with a natural language processing algorithm. Twenty-two volatile organic compounds (VOCs) in the exhaled breath and the prediction results of the TA model were used as predictors to develop the ETBA model using an extreme gradient boosting algorithm. A breath analysis model was developed based on the 22 VOCs. The BA and TA models were compared with the ETBA model. The ETBA model achieved a sensitivity of 94.3%, a specificity of 77.3%, and an accuracy of 87.7% with the validation set. The radiologist diagnosis performance with the validation set had a sensitivity of 74.3%, a specificity of 59.1%, and an accuracy of 68.1%. High sensitivity and specificity were obtained by the ETBA model compared with radiologist diagnosis. The ETBA model has the potential to provide sensitivity and specificity in CT screening of LC. This approach is rapid, non-invasive, multi-dimensional, and accurate for LC and BL diagnosis.
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Neoplasias Pulmonares , Compuestos Orgánicos Volátiles , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Estudios Retrospectivos , Sensibilidad y Especificidad , Compuestos Orgánicos Volátiles/análisis , Algoritmos , Pruebas Respiratorias/métodosRESUMEN
Expression profiling in spatially defined regions is crucial for systematically understanding tissue complexity. Here, we report a method of photo-irradiation for in-situ barcoding hybridization and ligation sequencing, named PBHL-seq, which allows targeted expression profiling from the photo-irradiated region of interest in intact fresh frozen and formalin fixation and paraffin embedding (FFPE) tissue samples. PBHL-seq uses photo-caged oligodeoxynucleotides for in situ reverse transcription followed by spatially targeted barcoding of cDNAs to create spatially indexed transcriptomes of photo-illuminated regions. We recover thousands of differentially enriched transcripts from different regions by applying PBHL-seq to OCT-embedded tissue (E14.5 mouse embryo and mouse brain) and FFPE mouse embryo (E15.5). We also apply PBHL-seq to the subcellular microstructures (cytoplasm and nucleus, respectively) and detect thousands of differential expression genes. Thus, PBHL-seq provides an accessible workflow for expression profiles from the region of interest in frozen and FFPE tissue at subcellular resolution with areas expandable to centimeter scale, while preserving the sample intact for downstream analysis to promote the development of transcriptomics.
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Perfilación de la Expresión Génica , Fijación del Tejido , Transcriptoma , Animales , Ratones , Perfilación de la Expresión Génica/métodos , Fijación del Tejido/métodos , Adhesión en Parafina , Encéfalo/metabolismo , Embrión de Mamíferos/metabolismoRESUMEN
Accurate image classification and retrieval are of importance for clinical diagnosis and treatment decision-making. The recent contrastive language-image pre-training (CLIP) model has shown remarkable proficiency in understanding natural images. Drawing inspiration from CLIP, pathology-dedicated CLIP (PathCLIP) has been developed, utilizing over 200,000 image and text pairs in training. While the performance the PathCLIP is impressive, its robustness under a wide range of image corruptions remains unknown. Therefore, we conduct an extensive evaluation to analyze the performance of PathCLIP on various corrupted images from the datasets of osteosarcoma and WSSS4LUAD. In our experiments, we introduce eleven corruption types including brightness, contrast, defocus, resolution, saturation, hue, markup, deformation, incompleteness, rotation, and flipping at various settings. Through experiments, we find that PathCLIP surpasses OpenAI-CLIP and the pathology language-image pre-training (PLIP) model in zero-shot classification. It is relatively robust to image corruptions including contrast, saturation, incompleteness, and orientation factors. Among the eleven corruptions, hue, markup, deformation, defocus, and resolution can cause relatively severe performance fluctuation of the PathCLIP. This indicates that ensuring the quality of images is crucial before conducting a clinical test. Additionally, we assess the robustness of PathCLIP in the task of image-to-image retrieval, revealing that PathCLIP performs less effectively than PLIP on osteosarcoma but performs better on WSSS4LUAD under diverse corruptions. Overall, PathCLIP presents impressive zero-shot classification and retrieval performance for pathology images, but appropriate care needs to be taken when using it.
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We present mCLIFY: a monomeric, bright, yellow, and long-lived fluorescent protein (FP) created by circular permutation of YPet, the brightest yellow FP from Aequorea Victoria for use in cellular and in vitro single molecule studies. mCLIFY retains the enhanced photophysical properties of YPET as a monomer at concentrations ≤ 40 µM. In contrast, we determined that YPet has a dimerization dissociation constant (K D 1-2) of 3.4 µM. Dimerization of YPet can cause homo-FRET, which underlies quantitative errors due to dimerization and homo-FRET. We determined the atomic structure of mCLIFY at 1.57 Å resolution and used its similarity with Venus for guided chromophore-targeted substitution studies to provide insights into its enhanced photophysical properties. The mutation V58L within the chromophore pocket improved quantum yield and extinction coefficient, making mCLIFY ~30% brighter than Venus. The extensive characterization of the photophysical and structural properties of YPet and mCLIFY presented here allowed us to reveal the basis of their long lifetimes and enhanced brightness and the basis of YPet's dimerization.
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The tumor microenvironment (TME) is a complex system composed mainly of tumor cells, mesenchymal cells and immune cells. Macrophages, also known as tumorassociated macrophages (TAMs), among innate immune cells, are some of the most abundant components of the TME. They may influence tumor growth and metastasis through interactions with other cell populations in the TME and have been associated with poor prognosis in a variety of tumors. Therefore, a better understanding of the role of TAMs in the TME may provide new insight into tumor therapy. In the present review, the origin and classification of TAMs in the TME were outlined and their polarization and dual effects on tumor cells, as well as emerging strategies for cancer therapies targeting TAMs, were discussed.
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Células Madre Mesenquimatosas , Neoplasias , Humanos , Macrófagos Asociados a Tumores , Macrófagos , Microambiente TumoralRESUMEN
Pauses regulate the rhythm of ribosomal protein synthesis. Mutations disrupting even minor pauses can give rise to improperly formed proteins and human disease. Such minor pauses are difficult to characterize by ensemble methods, but can be readily examined by single-molecule (sm) approaches. Here we use smFRET to carry out real-time monitoring of the expression of a full-length protein, the green fluorescent protein variant Emerald GFP. We demonstrate significant correlations between measured elongation rates and codon and isoacceptor tRNA usage, and provide a quantitative estimate of the effect on elongation rate of replacing a codon recognizing an abundant tRNA with a synonymous codon cognate to a rarer tRNA. Our results suggest that tRNA selection plays an important general role in modulating the rates and rhythms of protein synthesis, potentially influencing simultaneous co-translational processes such as folding and chemical modification.
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Transferencia Resonante de Energía de Fluorescencia , Extensión de la Cadena Peptídica de Translación , Secuencia de Aminoácidos , Codón/genética , Proteínas Fluorescentes Verdes/química , Modelos Moleculares , Datos de Secuencia Molecular , Mutación , Fragmentos de Péptidos/biosíntesis , Fragmentos de Péptidos/química , Fragmentos de Péptidos/genética , Conformación Proteica , ARN de Transferencia/genética , Ribosomas/genética , Ribosomas/metabolismoRESUMEN
OBJECTIVE: To investigate the impact of beta-elemene injection on the growth and alpha-tubule of human hepatocarcinoma HepG2 cells. METHODS: Cell proliferation was assessed by MTT assay. Cell cycle distribution was detected by flow cytometry (FCM). The mRNA expression of alpha-tubulin was measured by RT-PCR. Western blot analysis was used to determine protein expression of alpha-tubulin and the polymerization of tubulin. RESULTS: Beta-elemene injection inhibited HepG2 cells proliferation in a dose- and time-dependent manner; FCM analysis indicated beta-elemene injection induced cell cycle arrested at S phase. RT-PCR and western-blot analysis showed that beta-elemene injection down-regulated alpha-tublin at both mRNA and protein levels, presenting a dose-dependent manner. Moreover, beta-elemene injection reduced the polymerization of microtubules in a dose-dependent manner. CONCLUSIONS: Beta-elemene injection can inhibit the proliferation of hepatoma HepG2 cells and induce cell apoptosis, the mechanism might be partly related to the down-regulation of alpha-tubulin and inhibition of microtubular polymerization.
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One of the mechanisms by which tumor cells can evade the immune system is over activation of the programmed cell death protein-1 (PD-1) / programmed death-ligand 1 (PD-L1) pathway. The binding of PD-1 to its ligand PD-L1 can trigger an inhibitory signal for reducing T-cell proliferation, inhibiting the anticancer effect of T cells, and limiting the anti-tumor immunity of effectors T cell responses to protect tissues from immune-mediated tissue damage in the tumor microenvironment (TME). PD-1/PD-L1 immune checkpoint inhibitors have created a new pattern in cancer immunotherapy and can increase T cell- surveillance; therefore, the development of better clinical application of PD-1/PD-L1 inhibitors can significantly enhance antitumor immunity and prolong survival in GI cancer patients.