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1.
Int J Biol Macromol ; 267(Pt 2): 131514, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38608986

RESUMEN

The cell nucleus serves as the pivotal command center of living cells, and delivering therapeutic agents directly into the nucleus can result in highly efficient anti-tumor eradication of cancer cells. However, nucleus-targeting drug delivery is very difficult due to the presence of numerous biological barriers. Here, three antitumor drugs (DNase I, ICG: indocyanine green, and THP: pirarubicin) were sequentially triggered protein self-assembly to produce a nucleus-targeting and programmed responsive multi-drugs delivery system (DIT). DIT consisted of uniform spherical particles with a size of 282 ± 7.7 nm. The acidic microenvironment of tumors and near-infrared light could successively trigger DIT for the programmed release of three drugs, enabling targeted delivery to the tumor. THP served as a nucleus-guiding molecule and a chemotherapy drug. Through THP-guided DIT, DNase I was successfully delivered to the nucleus of tumor cells and killed them by degrading their DNA. Tumor acidic microenvironment had the ability to induce DIT, leading to the aggregation of sufficient ICG in the tumor tissues. This provided an opportunity for the photothermal therapy of ICG. Hence, three drugs were cleverly combined using a simple method to achieve multi-drugs targeted delivery and highly effective combined anticancer therapy.


Asunto(s)
Antineoplásicos , Núcleo Celular , Desoxirribonucleasa I , Doxorrubicina , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Animales , Ratones , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/administración & dosificación , Línea Celular Tumoral , Núcleo Celular/metabolismo , Desoxirribonucleasa I/metabolismo , Doxorrubicina/farmacología , Doxorrubicina/química , Doxorrubicina/administración & dosificación , Doxorrubicina/análogos & derivados , Portadores de Fármacos/química , Verde de Indocianina/química , Microambiente Tumoral/efectos de los fármacos , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos
2.
Small ; : e2307306, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38312110

RESUMEN

Intrinsically magnetic cells naturally occur within organisms and are believed to be linked to iron metabolism and certain cellular functions while the functional significance of this magnetism is largely unexplored. To better understand this property, an approach named Optical Tracking-based Magnetic Sensor (OTMS) has been developed. This multi-target tracking system is designed to measure the magnetic moment of individual cells. The OTMS generates a tunable magnetic field and induces movement in magnetic cells that are subsequently analyzed through a learning-based tracking-by-detection system. The magnetic moment of numerous cells can be calculated simultaneously, thereby providing a quantitative tool to assess cellular magnetic properties within populations. Upon deploying the OTMS, a stable population of magnetic cells in human peripheral monocytes is discovered. Further application in the analysis of clinical blood samples reveals an intriguing pattern: the proportion of magnetic monocytes differs significantly between systemic lupus erythematosus (SLE) patients and healthy volunteers. This variation is positively correlated with disease activity, a trend not observed in patients with rheumatoid arthritis (RA). The study, therefore, presents a new frontier in the investigation of the magnetic characteristics of naturally occurring magnetic cells, opening the door to potential diagnostic and therapeutic applications that leverage cellular magnetism.

3.
Talanta ; 265: 124855, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37406394

RESUMEN

Influenza A epidemics, which occur annually in varying degrees worldwide, is a global challenge to healthcare facilities owing to several limitations of the current detection methods. Therefore, the development of a rapid, convenient, and economical method for the early diagnosis of influenza A will aid clinical treatment and epidemic control. Currently, most of the commonly used clinical rapid tests utilize colloidal gold test strips that detect specific influenza virus antigens but are limited by low sensitivity. Therefore, this study combined catalytic hairpin assembly (CHA) with colloidal gold immunochromatographic assay (GICA) to develop a highly sensitive and visual CHA-GICA test strip. Clinical sample analysis revealed that the sensitivity of the assay was 81.8% and 74% under optimal (35 °C) and room temperature (25 °C) conditions, respectively. In conclusion, this study developed a rapid nucleic acid assay for detecting influenza A virus with high sensitivity and specificity, which can improve the clinical detection of influenza A.

4.
Int J Biol Macromol ; 245: 125475, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37353129

RESUMEN

Breast cancer is a highly prevalent malignancy worldwide among women with an increasing incidence in recent years. Triple-negative breast cancer (TNBC), a specific type of breast cancer, occurs primarily in young women and exhibits large tumor size, high clinical stage, and extremely poor prognosis with a high rate of lymph node, liver, and lung metastases. TNBC is insensitive to endocrine therapy and trastuzumab treatment, and there is an urgent need for effective therapeutics and treatment guidelines. However, investigations into antiangiogenic agents for the treatment of TNBC are ongoing. In this study, we successfully engineered a self-assembled protein nanocarrier TfRBP9-hVEGI-192-ELP fusion protein (TVEFP) to deliver the therapeutic protein, human vascular endothelial growth inhibitor (hVEGI-192). This was found to be effective in inhibiting tumor angiogenesis in vivo. The protein nanocarrier effectively inhibited the progression of TNBC in vivo and showed the behavior of self-assembly, thermoresponsiveness, enzyme stimulation-responsiveness, tumor-targeting, biocompatibility, and biodegradability. Near-infrared imaging studies showed that fluorescent dye-stained TVEFP effectively aggregated at the tumor site. The TVEFP nanocarrier significantly expands the application of the therapeutic protein hVEGI-192 and improves the imaging and biotherapeutic effects in TNBC, chiefly based on anti-angiogenesis effects.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Humanos , Femenino , Neoplasias de la Mama Triple Negativas/patología , Línea Celular Tumoral , Receptores ErbB/metabolismo
5.
iScience ; 26(4): 106390, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37034995

RESUMEN

Ever since the catalytic hairpin assembly (CHA) circuit has been highlighted as a powerful nucleic acid detection tool, nucleic acid detection methods based on CHA have been widely studied. However, the detection sensitivity of CHA-based methods is insufficient. The relatively high background signals resulting from the spontaneous reaction between the two hairpin probes is one of the major reasons for limiting the sensitivity of CHA. In this study, we established that the addition of deoxynucleotide triphosphates (dNTPs) to the reaction system can significantly reduce the background leakage of CHA. The dNTPs-CHA, coupled with a fluorescence lateral flow assay strip, is used for the rapid and highly sensitive detection of miRNA. It is capable of reliably detecting miRNA in serum samples down to a limit of 100 aM, which is an improvement in the lower detection limit by nearly five orders of magnitude compared to that of the pure CHA.

6.
Biomater Sci ; 11(5): 1754-1764, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36648428

RESUMEN

Accurately identifying multidrug-resistant (MDR) bacteria from clinical samples has long been a challenge. Herein, we report a simple and programmable dual-mode aptasensor called DAPT to reliably detect MDR bacteria. The DAPT method comprises two elements, namely the mode of dynamic light scattering (Mode-DLS) for ultrasensitive detection and the mode of fluorescence (Mode-Flu) for reliable quantification as a potent complement. Benefiting from the states of aptamer-modified gold nanoparticles (AptGNPs) sensitively changing from dispersion to aggregation, the proposed Mode-DLS achieved the rapid, specific, and ultrasensitive detection of methicillin-resistant Staphylococcus aureus (MRSA) at the limit of detection (LOD) of 4.63 CFU mL-1 in a proof-of-concept experiment. Simultaneously, the Mode-Flu ensured the accuracy of the detection, especially at a high concentration of bacteria. Moreover, the feasibility and universality of the DAPT platform was validated with four other superbugs by simply reprogramming the corresponding sequence. Overall, the proposed DAPT method based on a dual-mode aptasensor can provide a universal platform for the rapid and ultrasensitive detection of pathogenic bacteria due to its superior programmability.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Nanopartículas del Metal , Staphylococcus aureus Resistente a Meticilina , Oro , Inhibidores de Agregación Plaquetaria , Límite de Detección , Técnicas Biosensibles/métodos
7.
Polymers (Basel) ; 15(2)2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36679238

RESUMEN

Graphene conductive inks have attracted significant attention in recent years due to their high conductivity, corrosion resistance, and environmentally friendly nature. However, the dispersion of graphene in aqueous solution is still challenging. In this work, we synthesized an amphiphilic graft copolymer, polyvinyl alcohol-g-polyaniline (PVA-g-PANI), and studied the graphene dispersion prepared with the graft copolymer by high-speed shear dispersion. The amphiphilic graft copolymer can be used as a stabilizer and adhesive agent in graphene dispersion. Given the steric hindrance of the graft copolymer, the stability of graphene dispersion is improved by decreasing the probability of π-π stacking. PVA-g-PANI has a better stability on graphene dispersion than carboxymethylcellulose sodium (CMC-Na) and a mixture of PVA and PANI. The graft copolymer has only a slight effect on the conductivity of graphene dispersion due to the existence of conductive PANI, which is beneficial for preparing the graphene dispersion with good conductivity and adhesion. Graphene dispersion is well-adapted to screen printing and is very stable with regard to the sheet resistance bending cycle.

8.
Comput Intell Neurosci ; 2022: 5297605, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36317077

RESUMEN

Traffic sign detection is a challenging problem in the field of unmanned driving, particularly important in complex environments. We propose a method, based on the improved You only look once (YOLO) v4, to detect and recognize multiscale traffic signs in complex environments. This method employs an image preprocessing module that can classify and denoize images of complex environments and then input the images into the improved YOLOv4. We also design an improved feature pyramid structure to replace the original feature pyramid of YOLOv4. This structure uses an adaptive feature fusion module and a multiscale feature transfer mechanism to reduce putative information loss in the feature map generation process and improve the information transfer between deep and shallow features, enhancing the representation ability of feature pyramids. Finally, we use EIOU LOSS and Cluster-NMS to further improve the model performance. The experimental results on the fusion of Tsinghua-Tencent 100 K and our collected dataset show that the proposed method achieves an mAP of 81.78%. Compared to existing methods, our method demonstrates its superiority with regard to traffic sign detection.


Asunto(s)
Algoritmos , Redes Neurales de la Computación
9.
ACS Omega ; 7(38): 33830-33836, 2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-36188314

RESUMEN

Ureaplasma urealyticum is a common genital mycoplasma in men and women, which can cause reproductive tract infection and infertility, and is also related to adverse pregnancy outcomes and neonatal diseases. Pathogen culture and polymerase chain reaction (PCR) are the main methods for the diagnosis of U. urealyticum. However, pathogen culture takes too long, and PCR requires professional personnel and sophisticated instruments. Here, we report a simple, convenient, sensitive, and specific detection method, which combines catalytic hairpin assembly with a lateral flow immunoassay strip. Only a water bath and a fluorescence reader are needed to detect the results in 30 min. We can realize the point-of-care testing of U. urealyticum by this method. To verify this method, we selected 10 clinical samples for testing, and the test results were exactly the same as the clinical report.

10.
ACS Omega ; 7(17): 15074-15081, 2022 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-35557683

RESUMEN

Influenza viruses and respiratory syncytial virus (RSV) have contributed to severe respiratory infections, causing huge economic and healthcare burdens. To achieve rapid and precise detection of influenza viruses and RSV, we proposed a catalytic hairpin assembly (CHA) combined with the lateral flow immunoassay (CHA-LFIA) detection method. The presence of the target RNA triggers the initiation of CHA circuits. H1/H2 complexes, the amplified signal products, which were labeled with digoxin and biotin, were detected with a highly sensitive lateral flow immunoassay system. The sensitivity of the CHA-LFIA system to influenza A and B viruses and RSV reached up to 1, 1, and 5 pM, respectively. In addition, this method exhibited excellent capability for differentiating between target RNA and base-mismatched RNA. The results demonstrated that an enzyme-free, rapid, highly sensitive, and specific method had been developed to detect influenza A and B viruses and RSV.

11.
Cell Immunol ; 372: 104472, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35093731

RESUMEN

Immunotherapy has emerged as a promising treatment modality for HNSCC. However, only a small proportion of HNSCC patients experience clinical benefits from immunotherapy and identifying molecular markers that can serve as effective prognostic signatures and predictive indicators for immunotherapy response in patients with HNSCC is critical. CLEC10A has attracted attention because of its important role in improving the antitumor activity of immune cells. However, to our knowledge, no study has evaluated the role of CLEC10A in HNSCC prognosis, progression, and immune microenvironment. In the present study, we comprehensively analyzed expression profiles of CLEC10A and its association with tumor progression, HPV status, and survival of patients. Moreover, we explored the association between CLEC10A expression relative to immune infiltration and the response to immunotherapy. We explored the association between the timing of the receipt of palliative care relative to cancer diagnosis and survival. Our results revealed that CLEC10A has decreased expression in HNSCC compared with normal tissues, and that low expression of CLEC10A was associated with an advanced clinical stage and poor prognosis. Furthermore, a higher level of CLEC10A expression correlated with immune infiltration presence and response to immunotherapy in HNSCC. Thus, we demonstrated that CLEC10A could be a potential prognostic marker in patients with HNSCC, and a potential target for immunotherapy.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de Cabeza y Cuello/inmunología , Neoplasias de Cabeza y Cuello/metabolismo , Lectinas Tipo C/inmunología , Lectinas Tipo C/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/inmunología , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/inmunología , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Neoplasias de Cabeza y Cuello/genética , Humanos , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/patología , Mutación , Pronóstico , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología
12.
Acta Oncol ; 61(4): 505-515, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34879791

RESUMEN

Objective: This study aimed to explore the association of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) with cancer progression and prognosis in head and neck squamous cell carcinoma (HNSCC).Methods: Differentially expressed genes (DEGs) were identified by LIMMA package using R software. The correlation between the expression levels of MMPs and TIMPs in HNSCC cancer samples and adjacent normal tissue samples was performed using Pearson correlation analysis. The Kruskal-Wallis test (H-test) was used to determine the association between the expression level of MMPs/TIMPs and HNSCC clinical stage. The survival result was expressed as a KM curve, and the log-rank test was used for statistical analysis. Lasso regression and multivariate Cox regression analyses were used to examine whether the gene signature based on MMPs and TIMPs was an independent prognostic factor in patients with HNSCC.Results: Among the top 10 most up-regulated genes in HNSCC cancer tissues when compared with normal tissues, six genes belonged to the MMPs. Spearman correlation analysis revealed that only MMP11 and MMP23B were positively correlated with tumor stage. Survival analysis showed that patients with a high expression of MMP14, MMP20, TIMP1, and TIMP4 had a worse prognosis than low expression patients. Additionally, a novel five-gene (MMP3, MMP17, MMP19, MMP24, and TIMP1) signature was constructed and significantly associated with prognosis as an independent prognostic signature.Conclusions: Our data show that the accuracy of a single gene of MMP or TIMP as predictors of progression and prognosis of HNSCC is limited, although some studies have proposed that MMPs act as driving factors for cancer progression. The prediction performance of the five-gene signature prediction model was much better than that of the gene signatures based on every single gene in prognosis prediction.


Asunto(s)
Neoplasias de Cabeza y Cuello , Regulación Neoplásica de la Expresión Génica , Neoplasias de Cabeza y Cuello/genética , Humanos , Pronóstico , Carcinoma de Células Escamosas de Cabeza y Cuello/genética
13.
Talanta ; 239: 123122, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34890941

RESUMEN

Currently, PCR is the gold standard for the detection of hepatitis C virus (HCV). However, the PCR technique is complicated and time-consuming, which prevents its application and, clinical point-of-care testing (POCT). Herein, we report a POCT method with simplicity, high sensitivity and specificity, which consists of a catalytic hairpin assembly (CHA) signal amplification system coupled with a lateral flow immunochromatographic (LFIA) test strip for the detection of HCV. Two ingeniously designed hairpin probes were hybridized to form the H1-H2 duplex in the presence of the target DNA. The catalytic hairpin assembly which was characterized of isothermal and enzyme-free, was accomplished within 40 min and the reaction was then applied to a LFIA test strip. Only the H1-H2 duplex labeled with both digoxin and biotin could be captured by the test strip, and the fluorescence value was determined. In addition, we evaluated the application potential for the detection of clinical samples. The reported method demonstrated high sensitivity with a detectable minimum concentration at 1 fM and showed a good linear range from 10 nM to 10pM, and high specificity for various mismatched sequences. The results demonstrated that clinically positive samples could be successfully detected. In conclusion, the reported method is simple, rapid, and free of large-scale equipment. POCT is expected to be useful for HCV detection in clinic.


Asunto(s)
Técnicas Biosensibles , Hepatitis C , Catálisis , Hepacivirus/genética , Hepatitis C/diagnóstico , Humanos , Inmunoensayo , Límite de Detección
14.
Theranostics ; 10(26): 12158-12173, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33204335

RESUMEN

Rationale: Drug combination therapy for cancer treatment exerts a more potent antitumor effect. The targeted delivery and release of multiple drugs in a patient's body thus presents a more effective treatment approach, warranting further research. Methods: Two antitumor drugs (ICG: indocyanine green and THP: pirarubicin) were successfully screened to sequentially trigger self-assembling peptides (P60) to produce bacteria-sized particles (500-1000 nm, P60-ICG-THP). First, after mixing equal amount of P60 and ICG, trace amount of water (the mass ratio between P60 and water: 100:1) was used to trigger their assembly into P60-ICG. Subsequently, the assembly of P60-ICG and THP was further triggered by ultrasound treatment to produce P60-ICG-THP. Results: P60-ICG-THP constituted a cluster of several nanoparticles (50-100 nm) and possessed a negative charge. Owing to its size and charge characteristics, P60-ICG-THP could remain outside the cell membrane, avoiding the phagocytic clearance of blood and normal tissue cells in vivo. However, after localizing in the tumor, the size and charge switches of P60-ICG-THP, rapidly triggered by the low pH of the tumor microenvironment, caused P60-ICG-THP to segregate into two parts: (i) positively charged nanoparticles with a size of approximately 50 nm, and (ii) negatively charged particles of an uneven size. The former, mainly carrying THP (chemotherapeutic agent), could immediately cross the cell membrane and deliver pirarubicin into the nucleus of tumor cells. The latter, carrying ICG (used for photothermal therapy), could also enter the cell via the endocytosis pathway or accumulate in tumor blood vessels to selectively block the supply of nutrients and oxygen (cancer starvation). Both these particles could avoid the rapid excretion of ICG in the liver and were conducive to accumulation in the tumor tissue for photothermal therapy. Conclusion: Our drug delivery system not only achieves the precise subcellular delivery of two anticancer drugs due to their size and charge switches in the tumor site, but also provides a new strategy to combine chemotherapy, photothermal therapy, and cancer starvation therapy for the development of a highly efficient antitumor therapeutic regimen.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Neoplasias/terapia , Fotoquimioterapia/métodos , Terapia Fototérmica/métodos , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Hipoxia de la Célula/efectos de los fármacos , Línea Celular Tumoral , Membrana Celular/metabolismo , Permeabilidad de la Membrana Celular , Núcleo Celular/metabolismo , Doxorrubicina/administración & dosificación , Doxorrubicina/análogos & derivados , Doxorrubicina/farmacocinética , Liberación de Fármacos , Humanos , Concentración de Iones de Hidrógeno , Verde de Indocianina/administración & dosificación , Verde de Indocianina/farmacocinética , Nanopartículas/química , Neoplasias/patología , Tamaño de la Partícula , Péptidos/administración & dosificación , Péptidos/farmacocinética , Distribución Tisular , Microambiente Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Eur J Pharm Biopharm ; 152: 72-84, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32376370

RESUMEN

Decorating the membrane surface of vesicle carriers with proteins for targeted delivery has been achieved mainly by chemical methods. In this study, we report the rational design of a lipid-mimicking peptide for biomembrane decoration without chemical conjugation. A peptide Pm45 consisting of a hydrophobic helical tail and an anionic headgroup linked with an integrin-targeting RGD moiety was manually designed. Pm45 was synthesized and characterized, which confirmed an alpha-helix at the C-terminal. Pm45 spontaneously intercalated into the lipid bilayer as illustrated by quartz crystal of microbalance with dissipation (QCM-D), a calcein leakage assay, and TEM. The intercalation was accomplished within 10 min, and the ITC results indicated that the affinity of Pm45 binding with lipids was ~100-fold greater than that of the naturally occurring cell-penetrating peptide Ib-AMP4. In vitro cellular experiments indicated that the Pm45-decorated erythrocyte vesicles specifically bound and killed integrin αvß3-expressing MDA-MB-231 breast cancer cells. The targeting potential of Pm45-decorated erythrocyte vesicles was further evaluated in an MDA-MB-231 xenograft nude mouse model. The in vivo therapeutic effects indicated that the targeting vesicles significantly improved the therapeutic effect of encapsulated doxorubicin (DOX) compared with that of DOX or non-targeting vesicles. NIRF imaging implied that the targeting vesicles improved the pharmacokinetics of DOX in vivo and concentrated DOX in the tumour tissue at levels >50% higher than those achieved by non-targeting liposomes. This study reports a new method for liposome decoration as an alternative to chemical conjugation.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Membrana Eritrocítica/química , Membrana Eritrocítica/efectos de los fármacos , Lípidos/química , Péptidos/química , Animales , Línea Celular , Línea Celular Tumoral , Doxorrubicina/química , Sistemas de Liberación de Medicamentos/métodos , Femenino , Células HEK293 , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Membrana Dobles de Lípidos/química , Liposomas/química , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Mol Ther Nucleic Acids ; 20: 438-450, 2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-32276209

RESUMEN

Recently, the long noncoding RNA (lncRNA) plasmacytoma variant translocation 1 (PVT1) was reported to be involved in the pathogenesis of several cancers, including human colorectal cancer (CRC). However, the molecular basis for cancer initiation, development, and progression remains unclear. In this study, we observe that upregulated PVT1 is associated with poor prognosis and bad clinicopathological features of CRC patients. In vitro means of PVT1 loss in a CRC cell line inhibit cell proliferation, migration, and invasion. Furthermore, dual-luciferase reporter and RNA pull-down assays indicated that PVT1 binds to miR-16-5p, which has been shown to play strong tumor suppressive roles in CRC. Targeted loss of miR-16-5p partially rescues the suppressive effect induced by PVT1 knockdown. Vascular endothelial growth factor A (VEGFA), a direct downstream target of miR-16-5p, was suppressed by PVT1 knockdown in CRC cells. Overexpression of VEGFA is known to modulate the AKT signaling cascade by activating vascular endothelial growth factor receptor 1 (VEGFR1). We, therefore, show that PVT1 loss combined with miR-16-5p overexpression reduces tumor volume maximally when propagated within a mouse xenograft model. We conclude that the PVT1-miR-16-5p/VEGFA/VEGFR1/AKT axis directly coordinates the response in CRC pathogenesis and suggest PVT1 as a novel target for potential CRC therapy.

17.
Colloids Surf B Biointerfaces ; 179: 352-362, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-30991215

RESUMEN

A facile strategy with no modification processes was demonstrated to fabricate a pH-responsive end-capped mesoporous silica nanoparticle (MSN)-based drug delivery system (DDS). The simple but smart nanovalve systems were constructed by the self-assembly behavior of unbonded peptide-based amphiphile (P45) in the presence of Doxorubicin hydrochloride (Dox). A series of characterizations confirmed that the DDSs had been successfully fabricated. Dox molecules were entrapped by nanovalves in the pores of MSNs, and an in vitro release experiment demonstrated that the P45/Dox@MSNs exhibited "zero premature release" in the physical environment. However, an accelerated release was triggered by an acidic atmosphere in cellular cytosol. Moreover, detailed investigations confirmed that the enhanced cellular uptake of P45/Dox@MSNs due to the RGD motif of the nanovalves, exhibiting an obvious toxicity to cancer cells. Therefore, the DDSs constructed here can serve as a promising platform to realize targeted drug delivery and controlled drug release by using diversified bioactive native amphiphilic peptide.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/química , Péptidos/química , Dióxido de Silicio/química , Tensoactivos/química , Muerte Celular , Línea Celular Tumoral , Doxorrubicina , Liberación de Fármacos , Humanos , Concentración de Iones de Hidrógeno , Nanopartículas/ultraestructura , Porosidad
18.
Oncotarget ; 7(43): 70100-70112, 2016 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-27661121

RESUMEN

A novel multifunctional nano-drug delivery system based on reversal of peptide charge was successfully developed for anticancer drug delivery and imaging. Mesoporous silica nano-particles (MSN) ~50 nm in diameter were chosen as the drug reservoirs, and their surfaces were modified with HIV-1 transactivator peptide-fluorescein isothiocyanate (TAT-FITC) and YSA-BHQ1. The short TAT peptide labeled with FITC was used to facilitate intranuclear delivery, while the YSA peptide tagged with the BHQ1 quencher group was used to specifically bind to the tumor EphA2 membrane receptor. Citraconic anhydride (Cit) was used to invert the charge of the TAT peptide in neutral or weak alkaline conditions so that the positively charged YSA peptide could combine with the TAT peptide through electrostatic attraction. The FITC fluorescence was quenched by the spatial approach of BHQ1 after the two peptides bound to each other. However, the Cit-amino bond was unstable in the acidic atmosphere, so the positive charge of the TAT peptide was restored and the positively charged YSA moiety was repelled. The FITC fluorescence was recovered after the YSA-BHQ1 moiety was removed, and the TAT peptide led the nano-particles into the nucleolus. This nano-drug delivery system was stable at physiological pH, rapidly released the drug in acidic buffer, and was easily taken up by MCF-7 cells. Compared with free doxorubicin hydrochloride at an equal concentration, this modified MSN loaded with doxorubicin molecules had an equivalent inhibitory effect on MCF-7 cells. This nano-drug delivery system is thus a promising method for simultaneous cancer diagnosis and therapy.


Asunto(s)
Antineoplásicos/administración & dosificación , Núcleo Celular/metabolismo , Sistemas de Liberación de Medicamentos , Nanopartículas/metabolismo , Dióxido de Silicio/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Doxorrubicina/administración & dosificación , Doxorrubicina/química , Doxorrubicina/farmacología , Humanos , Solubilidad
19.
Oncotarget ; 7(36): 58445-58458, 2016 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-27533248

RESUMEN

In this study, we designed and fabricated self-assembly nanospheres, which consisted of a P45 peptide and doxorubicin (Dox). P45 is a hybrid peptide composed of an Arg-Gly-Asp motif linked to the human matrilin-1 C-terminal domain by a serine linker. The fabricated nanospheres had a uniform mulberry-like spherical shape, a diameter of 63 nm, excellent polydispersity, and high Dox drug-loading efficiency. In the presence of the RGD motif, the Dox/P45 nanospheres could specifically target A549 cells, which have high integrin αvß3 expression. Confocal laser scanning microscopy and flow cytometry results showed the enhanced cellular uptake of Dox/P45, and the CCK8 assay indicated the low cytotoxicity of the nanospheres to normal human embryonic kidney 293 cells. Furthermore, the fabricated nanospheres were stable in a physiological environment, but they disassembled and exhibited a rapid Dox release in an acidic atmosphere, allowing for a specific pH-sensitive release into cytosol after cellular uptake. These results suggest that natural amphiphilic peptides can be used as carriers of nanodrugs for targeting delivery as well as controlled drug release for cancer therapy.


Asunto(s)
Doxorrubicina/química , Portadores de Fármacos/química , Nanopartículas/química , Oligopéptidos/química , Péptidos/química , Células A549 , Secuencias de Aminoácidos , Dicroismo Circular , Citosol/metabolismo , Preparaciones de Acción Retardada , Citometría de Flujo , Células HEK293 , Humanos , Concentración de Iones de Hidrógeno , Células MCF-7 , Micelas , Microscopía Confocal , Neoplasias/tratamiento farmacológico , Polímeros/química
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