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Adaptive bionic self-correcting behavior offers an attractive property for chemical systems. Here, based on the dynamic feature of imine formation, we propose a solvent-responsive strategy for smart switching between an amorphous ionic polyimine membrane and a crystalline organic molecule cage without the addition of other building blocks. To adapt to solvent environmental constraints, the aldehyde and amine components undergo self-correction to form a polymer network or a molecular cage. Studies have shown that the amorphous film can be switched in acetonitrile to generate a discrete cage with bright birefringence under polarized light. Conversely, the membrane from the cage crystal conversion can be regained in ethanol. Such a membrane-cage interconversion can be cycled continuously at least 5 times by switching the two solvents. This work builds a bridge between the polymer network and crystalline molecules and offers prospects for smart dynamic materials.
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Adsorption, storage, and conversion of gases (e.g., carbon dioxide, hydrogen, and iodine) are the three critical topics in the field of clean energy and environmental mediation. Exploring new methods to prepare high-performance materials to improve gas adsorption is one of the most concerning topics in recent years. In this work, an ionic liquid solution process (ILSP), which can greatly improve the adsorption kinetic performance of covalent organic framework (COF) materials for gaseous iodine, is explored. Anionic COF TpPaSO3 H is modified by amino-triazolium cation through the ILSP method, which successfully makes the iodine adsorption kinetic performance (K80% rate) of ionic liquid (IL) modified COF AC4 tirmTpPaSO3 quintuple compared with the original COF. A series of experimental characterization and theoretical calculation results show that the improvement of adsorption kinetics is benefited from the increased weak interaction between the COF and iodine, due to the local charge separation of the COF skeleton caused by the substitution of protons by the bulky cations of ILs. This ILSP strategy has competitive help for COF materials in the field of gas adsorption, separation, or conversion, and is expected to expand and improve the application of COF materials in energy and environmental science.
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Treg are known to have a central role in orchestrating immune responses, but less is known about the destiny of Treg after being activated by specific Ags. This study aimed to investigate the role of superoxide dismutase, an active molecule in the regulation of oxidative stress in the body, in the prevention of Treg apoptosis induced by specific Ags. Ag-specific Tregs were isolated from the DO11.10 mouse intestine. A food allergy mouse model was developed with ovalbumin as the specific Ag and here, we observed that exposure to specific Ag induced Treg apoptosis through converting the precursor of TGF-ß to its mature form inside the Tregs. Oxidative stress was induced in Tregs upon exposure to specific Ags, in which Smad3 bound the latency-associated peptide to induce its degradation, converting the TGF-ß precursor to its mature form, TGF-ß. Suppressing oxidative stress in Tregs alleviated the specific Ag-induced Treg apoptosis in in vitro experiments and suppressed experimental food allergy by preventing the specific Ag-induced Treg apoptosis in the intestine. In conclusion, exposure to specific Ags induces Treg apoptosis and it can be prevented by upregulating superoxide dismutase or suppressing reactive oxidative species in Tregs.
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Antígenos/inmunología , Apoptosis/inmunología , Estrés Oxidativo/inmunología , Linfocitos T Reguladores/inmunología , Animales , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos BALB C , Ovalbúmina/inmunología , Proteína smad3/inmunología , Superóxido Dismutasa/inmunología , Factor de Crecimiento Transformador beta/inmunología , Regulación hacia Arriba/inmunologíaRESUMEN
BACKGROUND: Accumulating evidence demonstrated that long noncoding RNAs (lncRNAs) played important regulatory roles in many cancer types. However, the role of lncRNAs in gastric cancer (GC) progression remains unclear. METHODS: RT-qPCR assay was performed to detect the expression of HNF1A-AS1 in gastric cancer tissues and the non-tumourous gastric mucosa. Overexpression and RNA interference approaches were used to investigate the effects of HNF1A-AS1 on GC cells. Insight into competitive endogenous RNA (ceRNA) mechanisms was gained via bioinformatics analysis, luciferase assays and an RNA-binding protein immunoprecipitation (RIP) assay, RNA-FISH co-localisation analysis combined with microRNA (miRNA)-pulldown assay. RESULTS: This study displayed that revealed expression of HNF1A-AS1 was associated with positive lymph node metastasis in GC. Moreover, HNF1A-AS1 significantly promoted gastric cancer invasion, metastasis, angiogenesis and lymphangiogenesis in vitro and in vivo. In addition, HNF1A-AS1 was demonstrated to function as a ceRNA for miR-30b-3p. HNF1A-AS1 abolished the function of the miRNA-30b-3p and resulted in the derepression of its target, PIK3CD, which is a core oncogene involved in the progression of GC. CONCLUSION: This study demonstrated that HNF1A-AS1 worked as a ceRNA and promoted PI3K/AKT signalling pathway-mediated GC metastasis by sponging miR-30b-3p, offering novel insights of the metastasis mechanism in GC.
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Regulación Neoplásica de la Expresión Génica/genética , MicroARNs/metabolismo , ARN Largo no Codificante/metabolismo , Neoplasias Gástricas/patología , Anciano , Animales , Movimiento Celular/genética , Proliferación Celular/genética , Femenino , Xenoinjertos , Humanos , Masculino , Ratones , Ratones Desnudos , MicroARNs/genética , Persona de Mediana Edad , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Largo no Codificante/genética , Transducción de Señal/fisiología , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismoRESUMEN
The inorganic semiconductor is an attractive material in sewage disposal and solar power generation. The main challenges associated with environment-sensitive semiconductors are structural degradation and deactivation caused by the unfavorable environment. Here, inspired by the pomegranate, a self-protection strategy based on the self-assembly of silver chloride (AgCl) particles is reported. The distributed photosensitive AgCl particles can be encapsulated by themselves through mixing aqueous silver nitrate and protic ionic liquids (PILs). A probable assembling mechanism is proposed based on the electrostatic potential investigation of PILs cations. The AgCl particles inside the shell maintain their morphology and structure well after 6 months light-treatment. Moreover, they exhibit excellent photocatalytic activity, same as newly prepared AgCl particles, for degradation of methyl orange (MO), neutral red (NR), bromocresol green (BG), rhodamine B (RhB), Congo red (CR), and crystal violet (CV).
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Accurate estimation of the level of benzoyl peroxide (BPO) is of considerable significance because of its threat to humanity and environment. Several research efforts have been devoted to the detection of BPO by fluorescent method with high sensitivity and selectivity. However, it remains challenging to eliminate the interference of H2O2 due to its similar properties to BPO. In this work, the first demonstration of fluorescent and colorimetric probe for specific detection of BPO without the disturbance of H2O2 was achieved by curcumin-based ionic liquid (CIL) that possesses simple fabrication, good biocompatibility, and low cost. The fluorescence quenches and emission peak blue-shifts once the probe selectively interacts with BPO, whereas the other possible interfering agents, including H2O2, do not have this phenomenon. The probe CIL exhibits prominent sensitivity for BPO sensing and enables the detection limit at levels as ultralow as 10 nM. The local detection of BPO in practical samples is realized by visualization using a portable device derived from CIL-based liquid atomizer.
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Peróxido de Benzoílo/análisis , Curcumina/química , Colorantes Fluorescentes/química , Líquidos Iónicos/química , Compuestos de Amonio Cuaternario/química , Colorimetría/métodos , Contaminación de Medicamentos/prevención & control , Contaminantes Ambientales/análisis , Harina/análisis , Contaminación de Alimentos/análisis , Límite de Detección , Espectrometría de Fluorescencia/métodos , Triticum/químicaRESUMEN
BACKGROUND: The aim of the study was to present long-term results of mandibular growth in pediatric parotid gland carcinoma survivors treated with interstitial brachytherapy. PROCEDURE: Twenty-five survivors of pediatric parotid gland carcinoma treated with iodine-125 seed interstitial brachytherapy were included for quantitative analysis, including three dimensional (3D) cephalometry and measurement of mandibular volume. RESULTS: 3D cephalometry showed that the median fore-and-aft increments of the lengths of the condyle, the ramus, and the body of the mandible were 1.23, 0.19, and 1.66 mm for the affected side, respectively, and were 1.37, 1.95, and 3.42 mm for the unaffected side, respectively. The difference in increments of the ramus was statistically significant between the affected side and the unaffected side (P = 0.003; P < 0.05). Moreover, mandibular volume measurements showed that the median fore-and-aft increments of the volumes of the condyle, the ramus, and the body of the mandible were 290.62, 220.14, and 1706.40 mm3 for the affected side, respectively, and were 269.15, 370.40, and 1469.86 mm3 for the unaffected side, respectively. The difference in increments was statistically significant between the affected side and the unaffected side for the ramus (P = 0.005; P < 0.05) and the body (P = 0.043; P < .05). CONCLUSION: Mandibular growth was affected by interstitial brachytherapy, especially for the ramus, in pediatric parotid gland carcinoma survivors treated with interstitial brachytherapy. Nevertheless, the impact was mild in these survivors.
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Braquiterapia/efectos adversos , Carcinoma/radioterapia , Radioisótopos de Yodo/uso terapéutico , Mandíbula/efectos de la radiación , Neoplasias de la Parótida/radioterapia , Traumatismos por Radiación/etiología , Adolescente , Cefalometría , Niño , Femenino , Humanos , Imagenología Tridimensional , Masculino , Mandíbula/crecimiento & desarrollo , Tamaño de los Órganos , Traumatismos por Radiación/fisiopatología , Radioterapia Adyuvante/efectos adversos , SobrevivientesRESUMEN
Changes in temperature are known to cause a variety of physiological stress responses in insects and mites. Thermal stress responses are usually associated with the increased generation of reactive oxygen species (ROS), resulting in oxidative damage. In this study, we examined the time-related effect (durations for 1, 2, 3, and 5 h) of thermal stress conditions-i.e., relatively low (0, 5, 10, and 15 °C) or high (35, 38, 41, and 44 °C) temperatures-on the activities of antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), peroxidase (POX), glutathione S-transferases (GSTs), and total antioxidant capacity (T-AOC) of the predatory mite Neoseiulus cucumeris. Also the lipid peroxidation (LPO) levels of the predatory mite were measured under thermal stress conditions. The results confirmed that thermal stress results in a condition of so-called oxidative stress and the four antioxidant enzymes play an important role in combating the accumulation of ROS in N. cucumeris. CAT and POX activity changed significantly when the mites were exposed to cold and heat shock, respectively. The elevated levels of SOD and GSTs activity, expressed in a time-dependent manner, may have an important role in the process of antioxidant response to thermal stress. However, the levels of LPO in N. cucumeris were high, serving as an important signal that these antioxidant enzyme-based defense mechanisms were not always adequate to counteract the surplus ROS. Thus, we hypothesize that thermal stress, especially extreme temperatures, may contribute much to the generation of ROS in N. cucumeris, and eventually to its death.
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Antioxidantes/metabolismo , Peroxidación de Lípido , Ácaros/fisiología , Estrés Fisiológico , Animales , Catalasa/metabolismo , Frío , Glutatión Transferasa/metabolismo , Calor , Ácaros/enzimología , Ácaros/metabolismo , Peroxidasa/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismoRESUMEN
We report an electrochemical device for portable on-site detection of gaseous CH3I based on PVIm-F for the first time. The device achieves detection of gaseous CH3I with a significant selectivity and a low detection limit (0.474 ppb) in 20 min at 50 °C and 50% relative humidity, which is of great significance for achieving real-time on-site monitoring of radioactive hazardous environments.
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Along with the development of nuclear power, concerns about radioactive emissions and the potential for nuclear leakage have been widely raised, particularly of harmful iodine isotopes. However, as a significant component of nuclear air waste, the enrichment and detection of air-dispersed gaseous iodine remain a challenge. In this work, it is focused on developing an attraction-immobilization-detection strategy-based fluorescence method for the on-site detection of volatile iodine, by employing a photoluminescent ionic polyimine network-polyvinylpyrrolidone (IPIN-PVP) composite membrane. This strategy synergizes ion-induced dipole interactions from IPIN and complexation effects from PVP, allowing effective iodine enrichment and immobilization. As a result, the optimized IPIN-PVP membrane exhibits rapid response times of 5 s and a low detection limit of 4.087 × 10-8 m for gaseous iodine. It also introduces a portable handheld detection device that utilizes the composite membrane, offering a practical solution for real-time on-site detection of volatile iodine. This innovation enhances nuclear safety measures and disaster management by providing rapid and reliable iodine detection capabilities.
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Hazardous biological pathogens in the air pose a significant public environmental health concern as infected individuals emit virus-laden aerosols (VLAs) during routine respiratory activities. Mask-wearing is a key preventive measure, but conventional filtration methods face challenges, particularly in high humidity conditions, where electrostatic charge decline increases the risk of infection. This study introduces a bio-based air filter comprising glycine ionic liquids (GILs) and malleable polymer composite (GILP) with high polarity and functional group density, which are wrapped around a melamine-formaldehyde (MF) resin skeleton, forming a conductive, porous GIL functionized ionic network air filter (GILP@MF). When subjected to low voltage, the GILP@MF composite efficiently captures VLAs including nanoscale virus particles through the enhanced electrostatic attraction, especially in facing high humidity bioaerosols exhaled by human body. The filtration/collection efficiency and quality factor can reach 98.3% and 0.264 Pa-1 at 0.1 m s-1, respectively. This innovative filter provides effective VLA protection and offers potential for non-invasive respiratory virus sampling, advancing medical diagnosis efforts.
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Líquidos Iónicos , Humanos , Electricidad Estática , Tamaño de la Partícula , Filtración , AerosolesRESUMEN
Shewanella putrefaciens (S. putrefaciens) is one of the main microorganisms in soil bioreactors, which mainly immobilizes uranium through reduction and mineralization processes. However, the effects of elements such as phosphorus and ZVI, which may be present in the actual environment, on the mineralization and reduction processes are still not clearly understood and the environment is mostly in the absence of oxygen. In this study, we ensure that all experiments are performed in an anaerobic glove box, and we elucidate through a combination of macroscopic experimental findings and microscopic characterization that the presence of inorganic phosphates enhances the mineralization of uranyl ions on the surface of S. putrefaciens, while zero-valent iron (ZVI) facilitates the immobilization of uranium by promoting the reduction of uranium by S. putrefaciens. Interestingly, when inorganic phosphates and ZVI co-exist, both the mineralization and reduction of uranium on the bacterial surface are simultaneously enhanced. However, these two substances exhibit a certain degree of antagonism in terms of uranium immobilization by S. putrefaciens. Furthermore, it is found that the influence of pH on the mineralization and reduction of uranyl ions is far more significant than that of inorganic phosphates and ZVI. This study contributes to a better understanding of the environmental fate of uranium in real-world settings and provides valuable theoretical support for the bioremediation and risk assessment of uranium contamination.
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Shewanella putrefaciens , Uranio , Hierro/química , Uranio/química , Fosfatos , Anaerobiosis , IonesRESUMEN
The inevitable usage of toxic lead impedes the commercialization of lead halide perovskite solar cells, especially considering lead ions potentially unseals from the discarded and damaged devices and consequently contaminates the environment. In this work, we proposed a poly(ionic liquid) (PIL) cohered sandwich structure (PCSS) to realize lead sequestration in perovskite solar cells by a water-proof and adhesive poly([1-(3-propionic acid)-3-vinylimidazolium] bis(trifluoromethanesulphonyl)imide (PPVI-TFSI). A transparent ambidextrous protective shield manufactured from PPVI-TFSI was achieved and applied in lead sequestration for perovskite solar cells. PCSS provides robustness and water-resistance, which improves device stability toward water erosion and extreme situations (such as acid, base, salty water, and hot water). PPVI-TFSI exhibited excellent affinity toward lead with adsorption capacity of 516 mg·g-1, which assisted to prevent lead leakage in abandoned devices as proved in the test of wheat germination vividly. PCSS provides a promising solution for complex lead sequestration and management issues, which contribute to the commercialization of perovskite solar cells.
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Covalent organic frameworks show great potential in gas adsorption/separation, biomedicine, device, sensing, and printing arenas. However, covalent organic frameworks are generally not dispersible in common solvents resulting in the poor processability, which severely obstruct their application in practice. In this study, we develop a convenient top-down process for fabricating solution-processable covalent organic frameworks by introducing intermolecular hydrogen bonding and π-π interactions from ionic liquids. The bulk powders of imine-linked, azine-linked, and ß-ketoenamine linked covalent organic frameworks can be dispersed homogeneously in optimal ionic liquid 1-methyl-3-octylimidazolium bromide after heat treatment. The resulting high-concentration colloids are utilized to create the covalent organic framework inks that can be directly printed onto the surface. Molecular dynamics simulations and the quantum mechanical calculations suggest that CâH···π and π-π interaction between ionic liquid cations and covalent organic frameworks may promote the formation of colloidal solution. These findings offer a roadmap for preparing solution-processable covalent organic frameworks, enabling their practical applications.
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A rapid and accurate COVID-19 diagnosis is a prerequisite for blocking the source of infection as soon as possible and taking the appropriate medical action. Herein, we developed GeneClick, a device for nucleic acid self-testing of SARS-CoV-2, consisting of three modules: a sampling kit, a microfluidic chip-based disposable cartridge, and an amplification reader. In addition, we evaluated the clinical performance of GeneClick using 2162 nasal swabs collected at three medical institutions, using three commercial RT-qPCR kits and an antigen self-test as references. Compared to RT-qPCR, the sensitivity and specificity of the GeneClick assay were 97.93% and 99.72%, respectively, with a kappa value of 0.979 (P â< â0.01). Of the 2162 samples, 2076 were also tested for SARS-CoV-2 antigens. Among the 314 positive samples identified by GeneClick assay, 63 samples were undetected by antigen tests. Overall, the GeneClick nucleic acid self-test demonstrated higher accuracy than the antigen-based detection. Based on the additional features, including simple operation, affordable price, portable device, and reliability of smartphone APP-driven sampling and result reporting, GeneClick offers a powerful tool for field-based SARS-CoV-2 detection in primary healthcare institutions or at-home use.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Prueba de COVID-19 , Autoevaluación , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
Detection of hazardous compounds can alleviate risk to human health. However, it remains a challenge to develop easy-to-use testing tools for carcinogenic aromatic amines. Herein, we presented a conjugated molecule-based aniline detector, mixed matrix membranes (MMMs), through the solution-processable strategy. The pentacene-based dispersed phase is achieved using the state-of-the-art ionic liquids (ILs) as the continuous phase, based on which MMMs are easily manufactured by a solution process. Moreover, molecular dynamics (MD) simulations and quantum mechanical calculations suggested that hydrogen bonding and π-π interaction between ILs cations and pentacene could promote the dissolution. These prepared MMMs can offer easy-operation and on-site detection of carcinogenic primary aromatic amines with eye-readable fluorescence signal. This work provides a paradigm for the design of a portable testing device for various hazardous compounds.
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Líquidos Iónicos , Aminas , Humanos , Hidrógeno , Enlace de Hidrógeno , Simulación de Dinámica MolecularRESUMEN
Public anxiety and concern from cesium pollution in oceans have been back on the agenda since tons of nuclear waste water were announced to be poured into oceans. Cesium ion can easily enter organisms and bioaccumulate in animals and plants, thus its harm is chronic to humans through food chains. Here we showed a kind of hybrid ionic liquid membrane (HILM) for detection of cesium ion in seawater through CsPbBr3 perovskite fluorescence. With sustainability in mind, HILM was built frugally. The lowest cost of HILM is below 3 cents per piece. The HILM can detect cesium ion quickly with eye-readable fluorescence signal. Ultracheap, portable, easy-to-use on-site detection device could offer benefit for personal security and applications in environment science and ecology in the future decades.
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Compuestos de Calcio , Cesio , Animales , Fluorescencia , Humanos , Óxidos , TitanioRESUMEN
Long noncoding RNAs (lncRNAs) are dysregulated in different cancer types, and thus have emerged as important regulators of the initiation and progression of human cancers. However, the biological functions and the underlying mechanisms responsible for their functions in gastric cancer (GC) remain poorly understood. Here, by lncRNA microarray, we identified 1414 differentially expressed lncRNAs, among which THAP7-AS1 was significantly upregulated in GC tissues compared with non-tumorous gastric tissues. High expression of THAP7-AS1 was correlated with positive lymph node metastasis and poorer prognosis. SP1, a transcription factor, could bind directly to the THAP7-AS1 promoter region and activate its transcription. Moreover, the m6A modification of THAP7-AS1 by METTL3 enhanced its expression depending on the "reader" protein IGF2BP1-dependent pathway. THAP7-AS1 promoted GC cell progression. Mechanistically, THAP7-AS1 interacted with the 1-50 Amino Acid Region (nuclear localization signal) of CUL4B through its 1-442 nt Sequence, and it promoted interaction between nuclear localization signal (NLS) and importin α1, and improved the CUL4B protein entry into the nucleus, repressing miR-22-3p and miR-320a expression by CUL4B-catalyzed H2AK119ub1 and the EZH2-mediated H3K27me3, subsequently activating PI3K/AKT signaling pathway to promote GC progression. Moreover, LV-sh-THAP7-AS1 treatment could suppress GC growth, invasion and metastasis, indicating that THAP7-AS1 may act as a promising molecular target for GC therapies. Taken together, our results show that THAP7-AS1, transcriptionally activated by SP1 and then modified by METTL3-mediated m6A, exerts oncogenic functions, by promoting interaction between NLS and importin α1 and then improving the CUL4B protein entry into the nucleus to repress the transcription of miR-22-3p and miR-320a.
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MicroARNs , ARN Largo no Codificante , Neoplasias Gástricas , Carcinogénesis/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Proteínas Cullin , Regulación Neoplásica de la Expresión Génica , Humanos , Metiltransferasas/genética , Metiltransferasas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Señales de Localización Nuclear/genética , Señales de Localización Nuclear/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Factor de Transcripción Sp1/genética , Factor de Transcripción Sp1/metabolismo , Neoplasias Gástricas/patologíaRESUMEN
Breast cancer (BC) is the most common malignant tumor in women worldwide. Metastasis is the main cause of BC-related death. The specific mechanism underlying BC metastasis remains obscure. Recently, PRSS22 was discovered to be involved in tumor development, however, its detailed biological function and regulatory mechanism in BC are unclear. Here, we characterized that PRSS22 expression is upregulated in BC tissues compared with non-tumorous breast tissues. Dual luciferase assays, bioinformatics analyses and chromatin immunoprecipitation (ChIP) assays indicated that transcription factor E2F1 directly binds to the PRSS22 promoter region and activates its transcription. Functionally, upregulation of PRSS22 promoted invasion and metastasis of BC cells in vitro and in vivo, whereas knockdown of PRSS22 inhibited its function. Mechanistically, the combination of PRSS22 and ANXA1 protein in BC cells was first screened by protein mass spectrometry analysis, and then confirmed by co-immunoprecipitation (Co-IP) and western blot assays. Co-overexpression of PRSS22 and ANXA1 could promote BC cell migration and invasion. We further demonstrated that PRSS22 promotes the cleavage of ANXA1 and in turn generates an N-terminal peptide, which initiates the FPR2/ERK signaling axis to increase BC aggressiveness.
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Neoplasias de la Mama , Femenino , Humanos , Neoplasias de la Mama/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular , Factor de Transcripción E2F1/metabolismo , Receptores de Formil Péptido/metabolismo , Receptores de Lipoxina/metabolismo , Transducción de Señal , Melanoma Cutáneo MalignoRESUMEN
Increasing studies have indicated that circular RNAs (circRNAs) play pivotal roles in various cancers. Here, we aimed to explore the roles of circRNAs in breast cancer. We identified a novel circRNA circKDM4B (hsa_circ_0002926) by whole-transcriptome sequencing and validated this by Real-time quantitative polymerase chain reaction (RT-qPCR) and Sanger sequencing. It was significantly decreased in breast cancer tissues compared with adjacent non-tumor tissues. Furthermore, circKDM4B, which is mainly localized in the cytoplasm, was more resistant to actinomycin D or ribonuclease R than its linear transcript KDM4B. In addition, the overexpression of circKDM4B inhibited cell migration and invasion in vitro, while knockdown of circKDM4B induced the opposite effects. In vivo, circKDM4B suppressed tumor growth and metastasis. Additionally, circKDM4B inhibited migration and tube formation of human umbilical vein endothelial cells (HUVECs) in vitro and angiogenesis in vivo. Mechanically, circKDM4B sponged miR-675 to upregulate the expression of NEDD4-like E3 ubiquitin protein ligase (NEDD4L), which catalyzes ubiquitination of PI3KCA, thereby inhibiting PI3K/AKT and VEGFA secretion. Collectively, these findings uncovered the tumor-suppressor role of circKDM4B in breast cancer, especially in angiogenesis and tumor metastasis, indicating that circKDM4B could be a potential therapeutic target for breast cancer progression.