RESUMO
BACKGROUND: Periodontitis is a chronic oral inflammatory disease that seriously affects people's quality of life. The purpose of our study was to investigate the correlation between the systemic immune inflammation index (SII) and periodontitis by utilizing a large national survey. This will establish a reference for the early identification and management of periodontitis. METHODS: This study comprised the adult US population who participated in a national periodontitis surveillance project during the six years from 2009 to 2014. Through the utilization of univariate and multivariate weighted logistic regression, we investigated the correlation between the systemic immune inflammation index and periodontitis. Additionally, we employed sensitivity analyses to evaluate the robustness of our findings. RESULTS: The study involved 10,366 participants with an average age of 51.00 years, of whom 49.45% were male (N = 5126) and 50.55% were female (N = 5240). The prevalence of periodontitis is estimated to be about 38.43% in the US adults aged 30 or older population. Our logistic regression models indicated a positive association between a SII higher than 978 × 109/L and periodontitis. The elder group (aged 50 or older) with SII higher than 978 × 109/L demonstrated a significant correlation with periodontitis in the fully adjusted model (Odds Ratio [OR] = 1.409, 95% Confidence Interval [CI] 1.037, 1.915, P = 0.022). However, there is no statistical difference among adults aged 30 to 50. The robustness of our findings was confirmed through sensitivity analyses. CONCLUSIONS: Our study highlights that SII is associated with periodontitis in a nationally representative sample of US adults. And the SII is significantly associated with a high risk of periodontitis in individuals aged 50 or older.
Assuntos
Periodontite , Qualidade de Vida , Adulto , Feminino , Masculino , Humanos , Pessoa de Meia-Idade , Estudos Transversais , Inflamação , Modelos LogísticosRESUMO
Artesunate (ART), a natural product isolated from traditional Chinese plant Artemisia annua, has not been extensively explored for its anti-melanoma properties. In our study, we found that ART inhibited melanoma cell proliferation and induced melanoma cell ferroptosis. Mechanistic study revealed that ART directly targets Ido1, thereby suppressing Hic1-mediated transcription suppression of Hmox1, resulting in melanoma cell ferroptosis. In CD8+ T cells, ART does not cause cell ferroptosis due to the low expression of Hmox1. It also targets Ido1, elevating tryptophan levels, which inhibits NFATc1-mediated PD1 transcription, consequently activating CD8+ T cells. Our study uncovered a potent and synergistic anti-melanoma efficacy arising from ART-induced melanoma cell ferroptosis and concurrently enhancing CD8+ T cell-mediated immune response both in vivo and in vitro through directly targeting Ido1. Our study provides a novel mechanistic basis for the utilization of ART as an Ido1 inhibitor and application in clinical melanoma treatment.
Assuntos
Artesunato , Ferroptose , Indolamina-Pirrol 2,3,-Dioxigenase , Melanoma , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Ferroptose/efeitos dos fármacos , Animais , Artesunato/farmacologia , Artesunato/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/patologia , Camundongos , Linhagem Celular Tumoral , Humanos , Camundongos Endogâmicos C57BL , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Heme Oxigenase-1/genéticaRESUMO
Single-molecule mechanochemical sensing (SMMS) is a novel biosensing technique using mechanical force as a signal transduction mechanism. In the mechanochemical sensing, the chemical binding of an analyte molecule to a sensing template is converted to mechanical signals, such as tensile force, of the template. Since mechanical force can be conveniently monitored by single-molecule tools, such as optical tweezers, magnetic tweezers, or Atomic Force Microscopy, mechanochemical sensing is often carried out at the single molecule level. In traditional format of ensemble sensing, sensitivity can be achieved via chemical or electrical amplifications, which are materials intensive and time-consuming. To address these problems, in 2011, we used the principle of mechanochemical coupling in a single molecular template to detect single nucleotide polymorphism (SNP) in DNA fragments. The single-molecule sensitivity in such SMMS strategy allows to removing complex amplification steps, drastically conserving materials and increasing temporal resolution in the sensing. By placing many probing units throughout a single-molecule sensing template, SMMS can have orders of magnitude better efficiency in the materials usage (i.e., high Atom Economy) with respect to the ensemble biosensing. The SMMS sensing probes also enable topochemical arrangement of different sensing units. By placing these units in a spatiotemporally addressable fashion, single-molecule topochemical sensors have been demonstrated in our lab to detect an expandable set of microRNA targets. Because of the stochastic behavior of single-molecule binding, however, it is challenging for the SMMS to accurately report analyte concentrations in a fixed time window. While multivariate analysis has been shown to rectify background noise due to stochastic nature of single-molecule probes, a template containing an array of sensing units has shown ensemble average behaviors to address the same problem. In this so-called ensemble single-molecule sensing, collective mechanical transitions of many sensing units occur in the SMMS sensing probes, which allows accurate quantification of analytes. For the SMMS to function as a viable sensing approach readily adopted by biosensing communities, the future of the SMMS technique relies on the reduction in the complexity and cost of instrumentation to report mechanical signals. In this account, we first explain the mechanism and main features of the SMMS. We then specify basic elements employed in SMMS. Using DNA as an exemplary SMMS template, we further summarize different types of SMMS which present multiplexing capability and increased throughput. Finally, recent efforts to develop simple and affordable high throughput methods for force generation and measurement are discussed in this Account for potential usage in the mechanochemical sensing.
Assuntos
Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , DNA/química , Fenômenos Mecânicos , Microscopia de Força Atômica , Pinças ÓpticasRESUMO
Binding between a ligand and a receptor is a fundamental step in many natural or synthetic processes. In biosensing, a tight binding with a small dissociation constant (Kd) between the probe and analyte can lead to superior specificity and sensitivity. Owing to their capability of evaluating competitors, displacement assays have been used to estimate Kd at the ensemble average level. At the more sensitive single-molecule level, displacement assays are yet to be established. Here, we developed a single-molecule displacement assay (smDA) in an optical tweezers instrument and used this innovation to evaluate the binding of the L2H2-6OTD ligands to human telomeric DNA G-quadruplexes. After measuring Kd of linear and dendrimer L2H2-6OTD ligands, we found that dendrimer ligands have enhanced binding affinity to the G-quadruplexes due to their polyvalent geometry. This increased binding affinity enhanced inhibition of telomerase elongation on a telomere template in a Telomerase Repeated Amplification Protocol (TRAP). Our experiments demonstrate that the smDA approach can efficiently evaluate binding processes in chemical and biological processes.
Assuntos
Dendrímeros , Quadruplex G , Telomerase , Humanos , Ligantes , Telomerase/metabolismo , Telômero/metabolismoRESUMO
BACKGROUND: Coronavirus disease 2019 (COVID-19) caused a series of biological changes in cancer patients which have rendered the original treatment ineffective and increased the difficulty of clinical treatment. However, the clinical treatment for cancer patients infected with COVID-19 is currently unavailable. Since bioinformatics is an effective method to understand undiscovered biological functions, pharmacological targets, and therapeutic mechanisms. The aim of this study was to investigate the influence of COVID-19 infection in cancer patients and to search the potential treatments. METHODS: Firstly, we obtained the COVID-19-associated genes from seven databases and analyzed the cancer pathogenic genes from Gene Expression Omnibus (GEO) databases, respectively. The Cancer/COVID-19-associated genes were shown by Venn analyses. Moreover, we demonstrated the signaling pathways and biological functions of pathogenic genes in Cancer/COVID-19. RESULTS: We identified that Go-Ichi-Ni-San complex subunit 1 (GINS1) is the potential therapeutic target in Cancer/COVID-19 by GEPIA. The high expression of GINS1 was not only promoting the development of cancers but also affecting their prognosis. Furthermore, eight potential compounds of Cancer/COVID-19 were identified from CMap and molecular docking analysis. CONCLUSION: We revealed the GINS1 is a potential therapeutic target in cancer patients infected with COVID-19 for the first time, as COVID-19 will be a severe and prolonged pandemic. However, the findings have not been verified actually cancer patients infected with COVID-19, and further studies are needed to demonstrate the functions of GINS1 and the clinical treatment of the compounds.
Assuntos
COVID-19 , Neoplasias , Humanos , Biologia Computacional , COVID-19/genética , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Neoplasias/genética , Pandemias , Proteínas de Ligação a DNARESUMO
Proliferation and metastasis are significantly malignant characteristics of human lung cancer, but the underlying molecular mechanisms are poorly understood. Chromobox 4 (CBX4), a member of the Polycomb group (PcG) family of epigenetic regulatory factors, enhances cellular proliferation and promotes cancer cell migration. However, the effect of CBX4 in the progression of lung cancer is not fully understood. We found that CBX4 is highly expressed in lung tumours compared with adjacent normal tissues. Overexpression of CBX4 significantly promotes cell proliferation and migration in human lung cancer cell lines. The knockdown of CBX4 obviously suppresses the cell growth and migration of human lung cancer cells in vitro. Also, the proliferation and metastasis in vivo are blocked by CBX4 knockdown. Furthermore, CBX4 knockdown effectively arrests cell cycle at the G0/G1 phase through suppressing the expression of CDK2 and Cyclin E and decreases the formation of filopodia through suppressing MMP2, MMP9 and CXCR4. Additionally, CBX4 promotes proliferation and metastasis via regulating the expression of BMI-1 which is a significant regulator of proliferation and migration in lung cancer cells. Taken together, these data suggest that CBX4 is not only a novel prognostic marker but also may be a potential therapeutic target in lung cancer.
Assuntos
Biomarcadores Tumorais/metabolismo , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Ligases/metabolismo , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/patologia , Complexo Repressor Polycomb 1/metabolismo , Proteínas do Grupo Polycomb/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Feminino , Humanos , Ligases/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Complexo Repressor Polycomb 1/genética , Proteínas do Grupo Polycomb/genética , Prognóstico , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Non-small cell lung cancer (NSCLC) is the major type of lung cancer with high morbidity and poor prognosis. Erlotinib, an inhibitor of epidermal growth factor receptor (EGFR), has been clinically applied for NSCLC treatment. Nevertheless, the erlotinib acquired resistance of NSCLC occurs inevitably in recent years. METHODS: Through analyzing two microarray datasets, erlotinib resistant NSCLC cells microarray (GSE80344) and NSCLC tissue microarray (GSE19188), the differentially expressed genes (DEGs) were screened via R language. DEGs were then functionally annotated by Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, which up-regulated more than 2-folds in both datasets were further functionally analyzed by Oncomine, GeneMANIA, R2, Coremine, and FunRich. RESULTS: We found that matrix metalloproteinase 1 (MMP1) may confer the erlotinib therapeutic resistance in NSCLC. MMP1 highly expressed in erlotinib-resistant cells and NSCLC tissues, and it associated with poor overall survival. In addition, MMP1 may be associated with COPS5 and be involve in an increasing transcription factors HOXA9 and PBX1 in erlotinib resistance. CONCLUSIONS: Generally, these results demonstrated that MMP1 may play a crucial role in erlotinib resistance in NSCLC, and MMP1 could be a prognostic biomarker for erlotinib treatment.
Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Biologia Computacional , Resistencia a Medicamentos Antineoplásicos/genética , Cloridrato de Erlotinib/farmacologia , Metaloproteinase 1 da Matriz/genética , Inibidores de Proteínas Quinases/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Linhagem Celular Tumoral , Biologia Computacional/métodos , Cloridrato de Erlotinib/uso terapêutico , Perfilação da Expressão Gênica , Ontologia Genética , Humanos , Neoplasias Pulmonares/genética , Metaloproteinase 1 da Matriz/metabolismo , Mutação , Prognóstico , Inibidores de Proteínas Quinases/uso terapêutico , Reprodutibilidade dos Testes , TranscriptomaRESUMO
The recent discovery of ultra-high binding affinities in cucurbit[7]uril (CB7)-based host-guest pairs in an aqueous environment has rendered CB7 a rather attractive material in analytical and biomedical applications. Due to the lack of a molecular platform that can follow the same host-guest complex during repetitive mechanical measurements, however, mechanical stabilities of the CB7 system have not been revealed, hindering its potential to rival widely used conjugation pairs, such as streptavidin-biotin. Here, we assembled a DNA template in which a flexible DNA linker was exploited to keep the host (CB7) and guest (adamantane) in proximity. This platform not only increased the efficiency of the single-molecule characterization in optical tweezers but also clearly revealed mechanical features of the same host-guest complex. We found that positively charged adamantane guest demonstrated higher mechanical stability (49 pN) than neutral adamantane (44 pN), a trend consistent with the chemical affinity between guest molecules and the CB7 host. Surprisingly, we found that a hexyl group adjacent to the adamantane served as a chaperone to assist the formation of the adamantane-CB7 pairs. The discovery of an unprecedented chaperone-assisted interaction mechanism provides new approaches to efficiently assemble host-guest-based supramolecules with increased mechanical stabilities, which can be exploited in various biomedical, biosensing, and materials fields.
Assuntos
Adamantano/química , Hidrocarbonetos Aromáticos com Pontes/química , DNA/química , Imidazóis/química , Pinças Ópticas , Imagem Individual de Molécula , Estresse MecânicoRESUMO
IR-783 is a kind of heptamethine cyanine dye that exhibits imaging, cancer targeting and anticancer properties. A previous study reported that its imaging and targeting properties were related to mitochondria. However, the molecular mechanism behind the anticancer activity of IR-783 has not been well demonstrated. In this study, we showed that IR-783 inhibits cell viability and induces mitochondrial apoptosis in human breast cancer cells. Exposure of MDA-MB-231 cells to IR-783 resulted in the loss of mitochondrial membrane potential (MMP), adenosine triphosphate (ATP) depletion, mitochondrial permeability transition pore (mPTP) opening and cytochrome c (Cyto C) release. Furthermore, we found that IR-783 induced dynamin-related protein 1 (Drp1) translocation from the cytosol to the mitochondria, increased the expression of mitochondrial fission proteins mitochondrial fission factor (MFF) and fission-1 (Fis1), and decreased the expression of mitochondrial fusion proteins mitofusin1 (Mfn1) and optic atrophy 1 (OPA1). Moreover, knockdown of Drp1 markedly blocked IR-783-mediated mitochondrial fission, loss of MMP, ATP depletion, mPTP opening and apoptosis. Our in vivo study confirmed that IR-783 markedly inhibited tumour growth and induced apoptosis in an MDA-MB-231 xenograft model in association with the mitochondrial translocation of Drp1. Taken together, these findings suggest that IR-783 induces apoptosis in human breast cancer cells by increasing Drp1-mediated mitochondrial fission. Our study uncovered the molecular mechanism of the anti-breast cancer effects of IR-783 and provided novel perspectives for the application of IR-783 in the treatment of breast cancer.
Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Carbocianinas/farmacologia , GTP Fosfo-Hidrolases/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Associadas aos Microtúbulos/genética , Dinâmica Mitocondrial/efeitos dos fármacos , Proteínas Mitocondriais/genética , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citocromos c/genética , Citocromos c/metabolismo , Dinaminas , Feminino , GTP Fosfo-Hidrolases/antagonistas & inibidores , GTP Fosfo-Hidrolases/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Nus , Proteínas Associadas aos Microtúbulos/antagonistas & inibidores , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Proteínas Mitocondriais/antagonistas & inibidores , Proteínas Mitocondriais/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Although immune checkpoint therapy has significantly improved the prognosis of patients with melanoma, urgent attention still needs to be paid to the low patient response rates and the challenges of precisely identifying patients before treatment. Therefore, it is crucial to investigate novel immunosuppressive mechanisms and targets in the tumor microenvironment in order to reverse tumor immune escape. In this study, we found that the cell cycle checkpoint Aurora kinase B (AURKB) suppressed the anti-tumor immune response, and its inhibitor, Tozasertib, effectively activated T lymphocyte cytokine release in vitro and anti-tumor immunity in vivo. Tozasertib significantly inhibited melanoma xenograft tumor growth by decreasing the number of inhibitory CD4+ Treg cells in the tumors, which, in turn, activated CD8+ T cells. Single-cell analysis revealed that AURKB suppressed anti-tumor immunity by increasing MIF-CD74/CXCR4 signaling between tumor cells and lymphocytes. Our study suggests that AURKB is a newly identified anti-tumor immunity suppressor, whose inhibitors may be developed as novel anti-tumor immunity drugs and may have synergistic anti-melanoma effects with immune checkpoint therapies.
Assuntos
Antineoplásicos , Melanoma , Humanos , Melanoma/patologia , Linfócitos T Reguladores , Linfócitos T CD8-Positivos , Antineoplásicos/uso terapêutico , Microambiente TumoralRESUMO
Recent advances in cancer immunotherapy, especially immune checkpoint inhibitors (ICIs), have revolutionized the clinical outcome of many cancer patients. Despite the fact that impressive progress has been made in recent decades, the response rate remains unsatisfactory, and many patients do not benefit from ICIs. Herein, we summarized advanced studies and the latest insights on immune inhibitory factors in the tumor microenvironment. Our in-depth discussion and updated landscape of tumor immunosuppressive microenvironment may provide new strategies for reversing tumor immune evasion, enhancing the efficacy of ICIs therapy, and ultimately achieving a better clinical outcome.
RESUMO
Cu2-xSe nanoparticles (Cu2-xSe NPs) as a new therapeutic drug platform is widely used in disease treatment due to their strong near-infrared optical absorption. In recent years, with their continuous expansion of applications in different fields, their own biological effects have received increasing attention. However, little is known about the effect of Cu2-xSe NPs on cancer cell. In this research, we found that Cu2-xSe NPs inhibited proliferation of HepG2 cells (IC50: 15.91µM) and SMMC-7721 cells (IC50: 43.15µM) and they mainly induced cell cycle arrest at the G2/M phase. Moreover, Cu2-xSe NPs inhibited HepG2 and SMMC-7721 cell migration and lamellopodia formation. Further studies indicated that Cu2-xSe NPs impaired mitochondrial respiration by inhibiting electron transport chain complex activity, thus reducing adenosine triphosphate levels. The insufficient energy supply subsequently impaired actin cytoskeleton assembly, ultimately inhibiting HepG2 and SMMC-7721 cell proliferation and migration. These findings suggest that Cu2-xSe NPs may have potentially antitumor activity, which might provide new insights of NPs into specific cancer treatment.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Nanopartículas , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Nanopartículas/uso terapêutico , Células Hep G2 , Proliferação de CélulasRESUMO
Src homolog and collagen homolog binding protein 1 (SHCBP1) binds to the SH2 domain of SHC-transforming protein 1 (SHC1) and is involved in midbody organization and cytokinesis completion. SHCBP1 has been reported to be a cancer driver gene, promoting cancer progression. However, the functional role and underlying mechanism of SHCBP1 in regulating lung adenocarcinoma (LUAD) cell proliferation and migration are incompletely understood. Here, we discovered that SHCBP1 is overexpressed in LUAD tissues and is associated with a poor prognosis. SHCBP1 knockdown inhibited LUAD cell proliferation and migration by arresting the cell cycle and preventing epithelial-mesenchymal transition (EMT) via decreasing cyclin-dependent kinase 1 (CDK1) expression. Mechanistically, CDK1 overexpression reversed SHCBP1 knockdown-induced inhibition of proliferation and migration, confirming CDK1 as a key downstream target of SHCBP1. In addition, we proposed that rucaparib may be a small-molecule inhibitor of SHCBP1 and validated both in vitro and in vivo that rucaparib inhibits cell proliferation and migration via suppression of the SHCBP1/CDK1 pathway in LUAD. Our study elucidates a newly identified role of SHCBP1 in promoting cell proliferation and migration in LUAD, and suggests rucaparib as a potential inhibitor for LUAD treatment.
Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Proteína Quinase CDC2/genética , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Proliferação de Células , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Movimento Celular , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proteínas Adaptadoras da Sinalização ShcRESUMO
Single-molecule techniques based on fluorescence and mechanochemical principles provide superior sensitivity in biological sensing. However, due to the lack of high throughput capabilities, the application of these techniques is limited in biophysics. Ensemble force spectroscopy (EFS) has demonstrated high throughput in the investigation of a massive set of molecular structures by converting mechanochemical studies of individual molecules into those of molecular ensembles. In this protocol, the DNA secondary structures (i-motifs) were unfolded in the shear flow between the rotor and stator of a homogenizer tip at shear rates up to 77796/s. The effects of flow rates and molecular sizes on the shear forces experienced by the i-motif were demonstrated. The EFS technique also revealed the binding affinity between DNA i-motifs and ligands. Furthermore, we have demonstrated a click chemistry reaction that can be actuated by shear force (i.e., mechano-click chemistry). These results establish the effectiveness of using shear force to control the conformation of molecular structures.
Assuntos
DNA , Fenômenos Mecânicos , Biofísica , DNA/química , Conformação Molecular , Análise EspectralRESUMO
Chiral communications exist in secondary structures of foldamers and copolymers via a network of noncovalent interactions within effective intermolecular force (IMF) range. It is not known whether long-range chiral communication exists between macromolecular tertiary structures such as peptide coiled-coils beyond the IMF distance. Harnessing the high sensitivity of single-molecule force spectroscopy, we investigate the chiral interaction between covalently linked DNA duplexes and peptide coiled-coils by evaluating the binding of a diastereomeric pair of three DNA-peptide conjugates. We find that right-handed DNA triple helices well accommodate peptide triple coiled-coils of the same handedness, but not with the left-handed coiled-coil stereoisomers. This chiral communication is effective in a range (<4.5 nm) far beyond canonical IMF distance. Small-angle X-ray scattering and molecular dynamics simulation indicate that the interdomain linkers are tightly packed via hydrophobic interactions, which likely sustains the chirality transmission between DNA and peptide domains. Our findings establish that long-range chiral transmission occurs in tertiary macromolecular domains, explaining the presence of homochiral pairing of superhelices in proteins.
Assuntos
DNA/química , Substâncias Macromoleculares/química , Simulação de Acoplamento Molecular , Domínios Proteicos , Interações Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Estrutura Molecular , Peptídeos/química , Estrutura Secundária de Proteína , Proteínas/química , EstereoisomerismoRESUMO
Mechanical unfolding of biomolecular structures has been exclusively performed at the single-molecule level by single-molecule force spectroscopy (SMFS) techniques. Here we transformed sophisticated mechanical investigations on individual molecules into a simple platform suitable for molecular ensembles. By using shear flow inside a homogenizer tip, DNA secondary structures such as i-motifs are unfolded by shear force up to 50 pN at a 77 796 s-1 shear rate. We found that the larger the molecules, the higher the exerted shear forces. This shear force approach revealed affinity between ligands and i-motif structures. It also demonstrated a mechano-click reaction in which a Cu(i) catalyzed azide-alkyne cycloaddition was modulated by shear force. We anticipate that this ensemble force spectroscopy method can investigate intra- and inter-molecular interactions with the throughput, accuracy, and robustness unparalleled to those of SMFS methods.
RESUMO
INTRODUCTION: Triple-negative breast cancer (TNBC) has the high degree of malignancy and aggressiveness. There is no targeted therapy drug. Many studies have shown that RBC membrane-coated nanoparticles achieve biological camouflage. In addition, the RGD module in the iRGD mediates the penetration of the vector across the tumor blood vessels to the tumor tissue space. Therefore, we developed iRGD-RM-(DOX/MSNs) by preparing MSNs loaded with doxorubicin as the core, and coating the surface of the MSNs with iRGD-modified RBC membranes. METHODS: iRGD-RM-(DOX/MSNs) were fabricated using physical extrusion. In addition, their physical and chemical characterization, hemolytic properties, in vivo acute toxicity and inflammatory response, in vitro and in vivo safety, and qualitative and quantitative cellular uptake by RAW 264.7 cells and MDA-MB-231 cells were evaluated and compared. Furthermore, we examined the antitumor efficacy of iRGD-RM-(DOX/MSN) nanoparticles in vitro and in vivo. RESULTS: iRGD-RM-(DOX/MSNs) have reasonable physical and chemical properties. iRGD-RM-(DOX/MSNs) escaped the phagocytosis of immune cells and achieved efficient targeting of nanoparticles at the tumor site. The nanoparticles showed excellent antitumor effects in vivo and in vitro. CONCLUSION: In this study, we successfully developed biomimetic iRGD-RM-(DOX/MSNs) that could effectively target tumors and provide a promising strategy for the effective treatment of TNBC.
Assuntos
Nanopartículas , Neoplasias de Mama Triplo Negativas , Linhagem Celular Tumoral , Doxorrubicina/uso terapêutico , Portadores de Fármacos/uso terapêutico , Humanos , Oligopeptídeos/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológicoRESUMO
Metastasis is the main cause of death in cancer patients. The efficacy of pharmacological therapy for cancer is limited by the heterogeneous nature of cancer cells and the lack of knowledge of microenvironments in metastasis. Evidence has shown that activated platelets possess both tumor-homing and metastasis-targeting properties via intrinsic cell adhesion molecules on platelets, and malaria protein VAR2CSA is able to specifically bind to oncofetal chondroitin sulfate, which is overexpressed on cancer cells with both epithelial and mesenchymal phenotypes. Inspired by these mechanisms, we developed a recombinant VAR2CSA peptide (rVAR2)-modified activated platelet-mimicking nanoparticles (rVAR2-PM/PLGA-ss-HA) by coating the surface of disulfide-containing biodegradable PLGA conjugate nanoparticles (PLGA-ss-HA) with an activated platelet membrane. The results demonstrated that the engineered 122 nm rVAR2-PM/PLGA-ss-HA inherited the innate properties of the activated platelet membrane and achieved enhanced homing to both primary and metastatic foci. The nanoparticles were endocytosed and responded to a high intracellular concentration of reduced glutathione, resulting in nanoparticle disintegration and the release of chemotherapeutic drugs to kill tumor cells. Thus, rVAR2-decorated activated platelet-targeting nanoparticles with controlled drug release provide a promising drug delivery strategy for efficient treatment of primary and metastatic cancer.
Assuntos
Antígenos de Protozoários/metabolismo , Plaquetas/química , Docetaxel/farmacologia , Sistemas de Liberação de Medicamentos , Neoplasias Pulmonares/tratamento farmacológico , Melanoma Experimental/tratamento farmacológico , Nanopartículas/administração & dosagem , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Membrana Celular/química , Sulfatos de Condroitina/metabolismo , Preparações de Ação Retardada , Docetaxel/química , Ácido Hialurônico/química , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Masculino , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/química , Ratos , Ratos Sprague-DawleyRESUMO
Lung cancer is one of the most intractable diseases with high incidence and mortality worldwide. Adenylate cyclase-associated protein 1 (CAP1), a well-known actin depolymerization factor, is recently reported to be an oncogene accelerating cancer cell proliferation. However, the physiological significance of CAP1 in lung cancer is incompletely understood and the novel functions of CAP1 in transcriptional regulation remain unknown. Here we found that CAP1 was highly expressed in lung cancer tissues and cells, which was also negatively associated with prognosis in lung cancer patients. Moreover, CAP1 promoted A549 cells proliferation by promoting protein synthesis to accelerate cell cycle progression. Mechanistically, we revealed that CAP1 facilitated cyclin-dependent kinase 9 (CDK9)-mediated RNA polymerases (Pol) II-Ser2 phosphorylation and subsequent transcription elongation, and CAP1 performed its function in this progress depending on its actin-depolymerization activity in nucleoplasm. Furthermore, our in vivo findings confirmed that CAP1-promoted A549 xenograft tumor growth was associated with CDK9-mediated Pol II-Ser2 phosphorylation. Our study elucidates a novel role of CAP1 in modulating transcription by promoting polymerase II phosphorylation and suggests that CAP1 is a newly identified biomarker for lung cancer treatment and prognosis prediction.