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1.
Cancer Lett ; : 217102, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38969157

RESUMEN

Triple-negative breast cancer (TNBC) is the most lethal subtype of breast cancer. Hypoxia-activated prodrugs (HAPs) have shown promise as potential therapeutic agents for TNBC. While increasing hypoxia levels may promote the HAP activation, it raises concerns regarding HIF1α-dependent drug resistance. It is desirable to develop a targeted approach that enhances tumor hypoxia for HAP activation without promoting HIF1α-dependent drug resistance in TNBC treatment. Herein, we proposed a multi-responsive carrier-free self-assembled nanomedicine named AQ4N@CA4T1ASO. This nanomedicine first targeted tumors by the TNBC-targeting aptamers (T1), and then disassembled in the reductive and acidic conditions within tumors. The released Combretastatin 4 (CA4) could exacerbate hypoxia, thereby promoting the conversion of inactive Banoxantrone (AQ4N) to its active form, AQ4. Simultaneously, the released antisense oligonucleotide (ASO) could attenuate hypoxia-induced HIF1α mRNA expression, thereby sensitizing the tumor to chemotherapy. Overall, this smart nanomedicine represents a profound targeted therapy strategy, combining "hypoxia-potentiating, hypoxia-activated, chemo-sensitization" approaches for TNBC treatment. In vivo study demonstrated significant suppression of tumor growth, highlighting the promising potential of this nanomedicine for future clinical translation.

2.
J Transl Med ; 22(1): 604, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951906

RESUMEN

BACKGROUND: Triple-negative breast cancer (TNBC) is a recurrent, heterogeneous, and invasive form of breast cancer. The treatment of TNBC patients with paclitaxel and fluorouracil in a sequential manner has shown promising outcomes. However, it is challenging to deliver these chemotherapeutic agents sequentially to TNBC tumors. We aim to explore a precision therapy strategy for TNBC through the sequential delivery of paclitaxel and fluorouracil. METHODS: We developed a dual chemo-loaded aptamer with redox-sensitive caged paclitaxel for rapid release and non-cleavable caged fluorouracil for slow release. The binding affinity to the target protein was validated using Enzyme-linked oligonucleotide assays and Surface plasmon resonance assays. The targeting and internalization abilities into tumors were confirmed using Flow cytometry assays and Confocal microscopy assays. The inhibitory effects on TNBC progression were evaluated by pharmacological studies in vitro and in vivo. RESULTS: Various redox-responsive aptamer-paclitaxel conjugates were synthesized. Among them, AS1411-paclitaxel conjugate with a thioether linker (ASP) exhibited high anti-proliferation ability against TNBC cells, and its targeting ability was further improved through fluorouracil modification. The fluorouracil modified AS1411-paclitaxel conjugate with a thioether linker (FASP) exhibited effective targeting of TNBC cells and significantly improved the inhibitory effects on TNBC progression in vitro and in vivo. CONCLUSIONS: This study successfully developed fluorouracil-modified AS1411-paclitaxel conjugates with a thioether linker for targeted combination chemotherapy in TNBC. These conjugates demonstrated efficient recognition of TNBC cells, enabling targeted delivery and controlled release of paclitaxel and fluorouracil. This approach resulted in synergistic antitumor effects and reduced toxicity in vivo. However, challenges related to stability, immunogenicity, and scalability need to be further investigated for future translational applications.


Asunto(s)
Aptámeros de Nucleótidos , Preparaciones de Acción Retardada , Liberación de Fármacos , Fluorouracilo , Nucleolina , Paclitaxel , Fosfoproteínas , Proteínas de Unión al ARN , Neoplasias de la Mama Triple Negativas , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Aptámeros de Nucleótidos/farmacología , Aptámeros de Nucleótidos/química , Humanos , Paclitaxel/uso terapéutico , Paclitaxel/farmacología , Línea Celular Tumoral , Animales , Femenino , Fluorouracilo/farmacología , Fluorouracilo/uso terapéutico , Proteínas de Unión al ARN/metabolismo , Fosfoproteínas/metabolismo , Oligodesoxirribonucleótidos/farmacología , Oligodesoxirribonucleótidos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto , Proliferación Celular/efectos de los fármacos , Oxidación-Reducción/efectos de los fármacos , Ratones Endogámicos BALB C
3.
ACS Nano ; 18(21): 13599-13606, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38742607

RESUMEN

The emergence of interlayer excitons (IX) in atomically thin heterostructures of transition metal dichalcogenides (TMDCs) has drawn great attention due to their unique and exotic optical and optoelectronic properties. Because of the spatially indirect nature of IX, its oscillator strength is 2 orders of magnitude smaller than that of the intralayer excitons, resulting in a relatively low photoluminescence (PL) efficiency. Here, we achieve the PL enhancement of IX by more than 2 orders of magnitude across the entire heterostructure area with a plasmonic lattice on mirror (PLoM) structure. The significant PL enhancement mainly arises from resonant coupling between the amplified electric field strength within the PLoM gap and the out-of-plane dipole moment of IX excitons, increasing the emission efficiency by a factor of around 47.5 through the Purcell effect. This mechanism is further verified by detuning the PLoM resonance frequency with respect to the IX emission energy, which is consistent with our theoretical model. Moreover, our simulation results reveal that the PLoM structure greatly alters the far-field radiation of the IX excitons preferentially to the surface normal direction, which increases the collection efficiency by a factor of around 10. Our work provides a reliable and universal method to enhance and manipulate the emission properties of the out-of-plane excitons in a deterministic way and holds great promise for boosting the development of photoelectronic devices based on the IX excitons.

4.
Mol Ther Nucleic Acids ; 35(1): 102146, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38444701

RESUMEN

Osteogenesis imperfecta (OI) is a rare genetic disease characterized by bone fragility and bone formation. Sclerostin could negatively regulate bone formation by antagonizing the Wnt signal pathway, whereas it imposes severe cardiac ischemic events in clinic. Our team has screened an aptamer that could promote bone anabolic potential without cardiovascular risk. However, the affinity of the aptamer is lower and needs to be improved. In the study, hydrophobic quinoline molecule with unique orientations (seven subtypes) were incorporated into key sites of a bone anabolic aptamer against sclerostin to form a modified aptamer library. Among all the quinoline modifications, 5-quinoline modification could shape the molecular recognition of modified aptamers to sclerostin to facilitate enhancing its binding to sclerostin toward the highest affinity by interacting with newly participated binding sites in sclerostin. Further, 5-quinoline modification could facilitate the modified aptamer attenuating the suppressed effect of the transfected sclerostin on both Wnt signaling and bone formation marker expression levels in vitro, promoting bone anabolism in OI mice (Col1a2+/G610C). The proposed quinoline-oriented modification strategy could shape the molecular recognition of modified aptamers to proteins to facilitate enhancing its binding affinity and therapeutic potency.

5.
Environ Pollut ; 347: 123713, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38462200

RESUMEN

Micro/nanoplastics (M/NPs) are the novel contaminants ubiquitous in the environment. Cadmium (Cd), a kind of heavy metal pollutant widely distributed, could potentially co-exist with PS-NPs in the environment. However, their combined effects on cardiomyocyte and its molecular mechanism in mammals remained ambiguous. Here, we examined whether PANoptosis, an emerging and complicated kind of programmed cell death, was involved in PS-NPs and Cd co-exposure-elicited cardiac injury. In this study, 60 male mice were orally subjected to environmentally relevant concentrations of PS-NPs (1 mg/kg) and/or CdCl2 (1.5 mg/kg) for 35 days. As we speculated, PS-NPs and Cd co-exposure affected the expression of pyroptosis(Caspase-1, Cleaved-Caspase-1, GSDMD, N-GSDMD, AIM2, Pyrin, NLRP3, IL-18, IL-1ß)-, apoptosis(Caspase-3, Cleaved-Caspase-3, Caspase-8, Cleaved-Caspase-8, Caspase-7, BAX)- and necroptosis (t-RIPK3, p-RIPK3, t-RIPK1, p-RIPK1, t-MLKL, p-MLKL, ZBP1)-related genes and protein, resulting in growth restriction and damaged myocardial microstructure in mice. Notably, the combined effects on Cd and PS-NPs even predominantly aggravated the toxic damage. Intriguingly, we fortuitously discovered PS-NPs and/or Cd exposure facilitated linear ubiquitination of certain proteins in mice myocardium. In summation, this study shed light toward the effects of Cd and PS-NPs on cardiotoxicity, advanced the understanding of myocardial PANoptosis and provided a scientific foundation for further exploration of the combined toxicological effects of PS-NPs and heavy metals.


Asunto(s)
Cadmio , Miocitos Cardíacos , Masculino , Animales , Ratones , Cadmio/toxicidad , Caspasa 3 , Caspasa 8 , Microplásticos , Poliestirenos , Mamíferos
6.
Nat Commun ; 15(1): 1500, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38374331

RESUMEN

Although elevated atmospheric CO2 concentration (eCO2) has substantial indirect effects on vegetation carbon uptake via associated climate change, their dynamics remain unclear. Here we investigate how the impacts of eCO2-driven climate change on growing-season gross primary production have changed globally during 1982-2014, using satellite observations and Earth system models, and evaluate their evolution until the year 2100. We show that the initial positive effect of eCO2-induced climate change on vegetation carbon uptake has declined recently, shifting to negative in the early 21st century. Such emerging pattern appears prominent in high latitudes and occurs in combination with a decrease of direct CO2 physiological effect, ultimately resulting in a sharp reduction of the current growth benefits induced by climate warming and CO2 fertilization. Such weakening of the indirect CO2 effect can be partially attributed to the widespread land drying, and it is expected to be further exacerbated under global warming.

7.
Opt Express ; 31(21): 34280-34291, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37859188

RESUMEN

We propose a new method for fabricating hybrid metasurfaces by combining Mie and plasmonic resonances. Our approach involves obtaining an ultrasmooth gold film and separately structuring monocrystalline silicon (c-Si) nanoantenna arrays, which are then wet-transferred and finally immobilized onto the gold film. The experimental and simulation analysis reveals the importance of the native oxide layer of Si and demonstrates fascinating dispersion curves with nanogap resonances and bound states in the continuum. The localized field enhancements in the nanogap cavities result from the coupling between multipolar Mie resonances and their mirror images in the gold film. This effective method improves our understanding of hybrid modes and offers opportunities for developing active metasurfaces, such as depositing c-Si nanoantenna arrays onto stretchable polydimethylsiloxane substrates or electro-optic and piezoelectric sensitive lithium niobate films for potential applications in MEMS, LiDAR, and beyond.

8.
Lipids Health Dis ; 22(1): 125, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37559117

RESUMEN

BACKGROUND: Accumulating evidence indicated that apolipoprotein B (apoB) was the principal lipid determinant of coronary artery disease (CAD). Nevertheless, the connection between apoB and angiographic progression of CAD remained undetermined. METHODS: Five hundred and forty-four CAD patients with twice coronary computed tomography angiography experiences were enrolled. The Gensini scoring system was used to assess angiographic progression. Incident angiographic progression was defined as an annual change rate of the Gensini score of > 1 point. The predictive efficacy of baseline apoB levels for angiographic progression was assessed using a receiver operating characteristic (ROC) curve. For comparative purposes, patients were categorized into three groups according to their baseline apoB tertiles. Furthermore, discordance analyses defined by the median were performed to assess the superiority of apoB over lipoprotein cholesterol in predicting angiographic progression of CAD. RESULTS: Angiographic progression was observed in 184 patients (33.8%) during a follow-up period of 2.2-year. The area under the ROC curve was 0.565 (0.522-0.607, P = 0.013). The incidence of angiographic progression was elevated with increasing apoB tertile after adjusting for confounding factors [odds ratio (OR) for the medium apoB tertile: 1.92, 95% confidence interval (CI): 1.15-3.19, P = 0.012; OR for the high apoB tertile: 2.05, 95%CI:1.17-3.60, P = 0.013]. Additionally, discordance analyses showed that the higher apoB group had a significantly higher risk of CAD progression in the fully adjusted model (all P < 0.05). CONCLUSIONS: ApoB could be used as an accurate and comprehensive indicator of angiographic progression in patients with CAD.


Asunto(s)
Apolipoproteínas B , Enfermedad de la Arteria Coronaria , Humanos , Colesterol , LDL-Colesterol , Angiografía por Tomografía Computarizada , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Factores de Riesgo
9.
Nano Lett ; 23(16): 7584-7592, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37539848

RESUMEN

Optical bound states in the continuum (BICs) offer strong interactions with quantum emitters and have been extensively studied for manipulating spontaneous emission, lasing, and polariton Bose-Einstein condensation. However, the out-coupling efficiency of quasi-BIC emission, crucial for practical light-emitting devices, has received less attention. Here, we report an adaptable approach for enhancing quasi-BIC emission from a resonant monocrystalline silicon (c-Si) metasurface through lattice and multipolar engineering. We identify dual-BICs originating from electric quadrupoles (EQ) and out-of-plane magnetic dipoles, with EQ quasi-BICs exhibiting concentrated near-fields near the c-Si nanodisks. The enhanced fractional radiative local density of states of EQ quasi-BICs overlaps spatially with the emitters, promoting efficient out-coupling. Furthermore, coupling the EQ quasi-BICs with Rayleigh anomalies enhances directional emission intensity, and we observe inherent opposite topological charges in the multipolarly controlled dual-BICs. These findings provide valuable insights for developing efficient nanophotonic devices based on quasi-BICs.

10.
Acta Biochim Biophys Sin (Shanghai) ; 55(8): 1213-1221, 2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37475547

RESUMEN

Roof plate-specific spondin 1 (R-spondin1, RSPO1) is a Wnt/ß-catenin signaling pathway activator that binds with Wnt ligands to stimulate the Wnt/ß-catenin signaling pathway, which is key to hair regeneration. However, it is not clear whether recombinant RSPO1 (rRSPO1) affects hair regeneration. Here, we treat C57BL/6 male mice with rRSPO1 and investigate the expression of the Wnt/ß-catenin signaling pathway and the activation of hair follicle stem cells in the dorsal skin. The mouse skin color score and hair-covered area are determined to describe hair growth, and the skin samples are subjected to H&E staining, western blot analysis and immunofluorescence staining to evaluate hair follicle development and the expressions of Wnt/ß-catenin signaling pathway-related proteins. We find that rRSPO1 activates mouse hair follicle stem cells (mHFSCs) and accelerates hair regeneration. rRSPO1 increases the hair-covered area, the number of hair follicles, and the hair follicle diameter and length. Moreover, rRSPO1 enhances the activity of Wnt/ß-catenin signaling pathway-related proteins and the expressions of HFSC markers, as well as mHFSC viability. These results indicate that subcutaneous injection of rRSPO1 can improve hair follicle development by activating the Wnt/ß-catenin signaling pathway, thereby promoting hair regeneration. This study demonstrates that rRSPO1 has the potential to treat hair loss by activating the Wnt/ß-catenin signaling pathway.


Asunto(s)
Cabello , Vía de Señalización Wnt , Ratones , Masculino , Animales , Ratones Endogámicos C57BL , Cabello/metabolismo , Folículo Piloso/metabolismo , Piel/metabolismo , beta Catenina/metabolismo
11.
Nanomaterials (Basel) ; 13(13)2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37446502

RESUMEN

Plasmon resonances can greatly enhance light-matter interactions of two-dimensional van der Waals materials. However, the quality factor of plasmonic resonances is limited. Here, we demonstrate a plasmonic quasi-bound state in the continuum (quasi-BIC), which is composed of gold nanorod pairs. Through controlling the rotation angle of the nanorods, the quality factor of the plasmonic BIC mode can be tuned. Simulation results show that the plasmonic BIC combines the advantages of high-quality factor from the BIC effect and small mode volume from plasmonic resonance. Experiment results show that the designed plasmonic BIC mode exhibits a quality factor higher than 15 at the wavelength of around 1250 nm. Through integrating the plasmonic bound state structure with monolayer molybdenum ditelluride (MoTe2), the exciton emission of MoTe2 in the PL spectrum split into two exciton-polariton modes, which is attributed to the high Q factor and strong interaction between the BIC mode and excitons of MoTe2.

12.
Colloids Surf B Biointerfaces ; 229: 113445, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37441838

RESUMEN

Chemodynamic therapy (CDT), which converts overexpressed hydrogen peroxide (H2O2) in tumor cells to hydroxyl radicals (•OH) by Fenton reactions, is considered a prospective strategy in anticancer therapy. However, the high level of glutathione (GSH) and poor Fenton catalytic efficiency contribute to the suboptimal efficiency of CDT. Herein, we present a multifunctional nanoplatform (CuFe2O4@HA) that can induce GSH depletion and combine with photothermal therapy (PTT) to enhance antitumor efficacy. CuFe2O4@HA nanoparticles could release Cu2+ and Fe3+ after entering tumor cells by targeting hyaluronic acid (HA). Subsequently, Cu2+ and Fe3+ were reduced to Cu+ and Fe2+ by GSH, where Cu+/Fe2+ significantly catalyzed H2O2 to produce a higher level of •OH, and the depletion of GSH disrupted the antioxidant capacity of the tumor. Therefore, depleting GSH substantially enhances the level of •OH in tumor cells. In addition, CuFe2O4@HA nanoparticles have considerable absorption in the near-infrared (NIR) region, which can stimulate excellent PTT effects. More importantly, the heat generated by PTT can further enhance the Fenton catalysis efficiency. In vitro and in vivo experiments have demonstrated the excellent tumor-killing effect of CuFe2O4@HA nanoparticles. This strategy overcomes the problem of insufficient CDT efficacy caused by GSH overexpression and poor catalytic efficiency. Moreover, this versatile nanoplatform provides a reference for self-enhanced CDT and PTT/CDT synergistic targeted therapy.


Asunto(s)
Ácido Hialurónico , Neoplasias , Humanos , Ácido Hialurónico/farmacología , Peróxido de Hidrógeno , Glutatión , Antioxidantes , Catálisis , Línea Celular Tumoral , Microambiente Tumoral
13.
Nat Commun ; 14(1): 4270, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37460531

RESUMEN

Two-dimensional (2D) materials have been considered promising candidates for future low power-dissipation and reconfigurable integrated circuit applications. However, 2D transistors with intrinsic ambipolar transport polarity are usually affected by large off-state leakage currents and small on/off ratios. Here, we report the realization of a reconfigurable Schottky junction field-effect transistor (SJFET) in an asymmetric van der Waals contact geometry, showing a balanced and switchable n- and p-unipolarity with the Ids on/off ratio kept >106. Meanwhile, the static leakage power consumption was suppressed to 10-5 nW. The SJFET worked as a reversible Schottky rectifier with an ideality factor of ~1.0 and a tuned rectifying ratio from 3 × 106 to 2.5 × 10-6. This empowered the SJFET with a reconfigurable photovoltaic performance in which the sign of the open-circuit voltage and photo-responsivity were substantially switched. This polarity-reversible SJFET paves an alternative way to develop reconfigurable 2D devices for low-power-consumption photovoltaic logic circuits.

14.
Small ; 19(38): e2301003, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37211708

RESUMEN

Bone is one of the prone metastatic sites of patients with advanced breast cancer. The "vicious cycle" between osteoclasts and breast cancer cells plays an essential role in osteolytic bone metastasis from breast cancer. In order to inhibit bone metastasis from breast cancer, NIR-II photoresponsive bone-targeting nanosystems (CuP@PPy-ZOL NPs) are designed and synthesized. CuP@PPy-ZOL NPs can trigger the photothermal-enhanced Fenton response and photodynamic effect to enhance the photothermal treatment (PTT) effect and thus achieve synergistic anti-tumor effect. Meanwhile, they exhibit a photothermal enhanced ability to inhibit osteoclast differentiation and promote osteoblast differentiation, which reshaped the bone microenvironment. CuP@PPy-ZOL NPs effectively inhibited the proliferation of tumor cells and bone resorption in the in vitro 3D bone metastases model of breast cancer. In a mouse model of breast cancer bone metastasis, CuP@PPy-ZOL NPs combined with PTT with NIR-II significantly inhibited the tumor growth of breast cancer bone metastases and osteolysis while promoting bone repair to achieve the reversal of osteolytic breast cancer bone metastases. Furthermore, the potential biological mechanisms of synergistic treatment are identified by conditioned culture experiments and mRNA transcriptome analysis. The design of this nanosystem provides a promising strategy for treating osteolytic bone metastases.


Asunto(s)
Neoplasias Óseas , Osteólisis , Animales , Ratones , Terapia Fototérmica , Microambiente Tumoral , Huesos/patología , Neoplasias Óseas/terapia , Neoplasias Óseas/patología , Osteoclastos , Osteólisis/terapia , Osteólisis/patología , Línea Celular Tumoral
15.
Cell Signal ; 107: 110677, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37028779

RESUMEN

RNF31, an atypical E3 ubiquitin ligase of the RING-between-RING protein family, is one of the important components of the linear ubiquitin chain complex LUBAC. It plays a carcinogenic role in a variety of cancers by promoting cell proliferation, invasion and inhibiting apoptosis. However, the specific molecular mechanism by which RNF31 exerts its cancer-promoting effects is still unclear. By analyzing the expression profile of RNF31-depleted cancer cells, we found that loss of RNF31 significantly resulted in the inactivation of the c-Myc pathway. We further showed that RNF31 played an important role in the maintenance of c-Myc protein levels in cancer cells by extending the half-life of c-Myc protein and reducing its ubiquitination. c-Myc protein levels are tightly regulated by the ubiquitin proteasome, in which the E3 ligase FBXO32 is required to mediate its ubiquitin-dependent degradation. We found that RNF31 inhibited the transcription of FBXO32 through EZH2-mediated trimethylation of histone H3K27 in the FBXO32 promoter region, leading to the stabilization and activation of c-Myc protein. Under this circumstance, the expression of FBXO32 was significantly increased in RNF31-deficient cells, promoting the degradation of c-Myc protein, inhibiting cell proliferation and invasion, increasing cell apoptosis, and ultimately blocking the progression of tumors. Consistent with these results, the reduced malignancy phenotype caused by RNF31 deficiency could be partially reversed by overexpression of c-Myc or further knockdown of FBXO32. Together, our results reveal a key association between RNF31 and epigenetic inactivation of FBXO32 in cancer cells, and suggest that RNF31 may be a promising target for cancer therapy.


Asunto(s)
Neoplasias , Ubiquitina , Humanos , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación , Neoplasias/genética , Epigénesis Genética , Proteínas Musculares/metabolismo , Proteínas Ligasas SKP Cullina F-box/genética
16.
Front Cell Dev Biol ; 11: 1091809, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36910146

RESUMEN

Nucleic acid aptamers are ssDNA or ssRNA fragments that specifically recognize targets. However, the pharmacodynamic properties of natural aptamers consisting of 4 naturally occurring nucleosides (A, G, C, T/U) are generally restricted for inferior binding affinity than the cognate antibodies. The development of high-affinity modification strategies has attracted extensive attention in aptamer applications. Chemically modified aptamers with stable three-dimensional shapes can tightly interact with the target proteins via enhanced non-covalent bonding, possibly resulting in hundreds of affinity enhancements. This review overviewed high-affinity modification strategies used in aptamers, including nucleobase modifications, fluorine modifications (2'-fluoro nucleic acid, 2'-fluoro arabino nucleic acid, 2',2'-difluoro nucleic acid), structural alteration modifications (locked nucleic acid, unlocked nucleic acid), phosphate modifications (phosphorothioates, phosphorodithioates), and extended alphabets. The review emphasized how these high-affinity modifications function in effect as the interactions with target proteins, thereby refining the pharmacodynamic properties of aptamers.

17.
Cell Death Dis ; 14(2): 83, 2023 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-36739418

RESUMEN

SEMA6A is a multifunctional transmembrane semaphorin protein that participates in various cellular processes, including axon guidance, cell migration, and cancer progression. However, the role of SEMA6A in clear cell renal cell carcinoma (ccRCC) is unclear. Based on high-throughput sequencing data, here we report that SEMA6A is a novel target gene of the VHL-HIF-2α axis and overexpressed in ccRCC. Chromatin immunoprecipitation and reporter assays revealed that HIF-2α directly activated SEMA6A transcription in hypoxic ccRCC cells. Wnt/ß-catenin pathway activation is correlated with the expression of SEMA6A in ccRCC; the latter physically interacted with SEC62 and promoted ccRCC progression through SEC62-dependent ß-catenin stabilization and activation. Depletion of SEMA6A impaired HIF-2α-induced Wnt/ß-catenin pathway activation and led to defective ccRCC cell proliferation both in vitro and in vivo. SEMA6A overexpression promoted the malignant phenotypes of ccRCC, which was reversed by SEC62 depletion. Collectively, this study revealed a potential role for VHL-HIF-2α-SEMA6A-SEC62 axis in the activation of Wnt/ß-catenin pathway. Thus, SEMA6A may act as a potential therapeutic target, especially in VHL-deficient ccRCC.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Semaforinas , Humanos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , beta Catenina/genética , beta Catenina/metabolismo , Carcinoma de Células Renales/patología , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Neoplasias Renales/metabolismo , Semaforinas/genética , Semaforinas/metabolismo , Regulación hacia Arriba , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo
18.
Biomater Sci ; 11(3): 828-839, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36453535

RESUMEN

In the complex and severe tumor microenvironment, the antitumor efficiency of nanomedicines is significantly limited by their low-efficacy monotherapy, non-tumor targeting, and systemic toxicity. Herein, to achieve tumor-targeted and enhanced chemodynamic/photothermal therapy (CDT/PTT), we fabricated an "all-in-one" biocompatible transferrin-loaded cobalt ferrate nanoparticle (CoFe2O4@Tf (CFOT)) with multiple functions by a simple solvothermal method and the following transferrin (Tf) functionalization. Upon exposure to 808 nm laser irradiation, CFOT, as a novel photothermal agent, exhibited outstanding phototherapeutic activity because of its excellent photothermal conversion efficiency (η = 46.5%) for high-performance PTT. Moreover, CFOT with multiple redox pairs could efficiently convert endogenous H2O2 to hazardous hydroxyl radicals (˙OH) via Fenton reactions while scavenging overexpressed GSH in the tumor microenvironment to realize self-reinforcing CDT. Importantly, CFOT undergoes a promoted Fenton-type reaction upon increasing the temperature under a photothermal effect and could augment PTT by high-level ˙OH, exhibiting a considerably enhanced synergistic therapeutic effect. In vitro and in vivo experimental results demonstrated that CFOT has good potential as an "all-in-one" nanoagent to combine photothermal, chemodynamic, and tumor targeting for efficient tumor elimination.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Transferrina , Peróxido de Hidrógeno , Terapia Fototérmica , Neoplasias/tratamiento farmacológico , Cobalto/farmacología , Microambiente Tumoral , Línea Celular Tumoral
19.
Glob Chang Biol ; 29(6): 1628-1647, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36524280

RESUMEN

Climate change alters surface water availability (WA; precipitation minus evapotranspiration, P - ET) and consequently impacts agricultural production and societal water needs, leading to increasing concerns on the sustainability of water use. Although the direct effects of climate change on WA have long been recognized and assessed, indirect climate effects occurring through adjustments in terrestrial vegetation are more subtle and not yet fully quantified. To address this knowledge gap, here we investigate the interplay between climate-induced changes in leaf area index (LAI) and ET and quantify its ultimate effect on WA during the period 1982-2016 at the global scale, using an ensemble of data-driven products and land surface models. We show that ~44% of the global vegetated land has experienced a significant increase in growing season-averaged LAI and climate change explains 33.5% of this greening signal. Such climate-induced greening has enhanced ET of 0.051 ± 0.067 mm year-2 (mean ± SD), further amplifying the ongoing increase in ET directly driven by variations in climatic factors over 36.8% of the globe, and thus exacerbating the decline in WA prominently in drylands. These findings highlight the indirect impact of positive feedbacks in the land-climate system on the decline of WA, and call for an in-depth evaluation of these phenomena in the design of local mitigation and adaptation plans.


Asunto(s)
Agricultura , Agua , Cambio Climático , Hojas de la Planta , Estaciones del Año , Ecosistema
20.
IEEE Trans Cybern ; PP2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36350864

RESUMEN

In an era of pervasive digitalization, the growing volume and variety of data streams poses a new challenge to the efficient running of data-driven optimization algorithms. Targeting scalable multiobjective evolution under large-instance data, this article proposes the general idea of using subsampled small-data tasks as helpful minions (i.e., auxiliary source tasks) to quickly optimize for large datasets-via an evolutionary multitasking framework. Within this framework, a novel computational resource allocation strategy is designed to enable the effective utilization of the minions while guarding against harmful negative transfers. To this end, an intertask empirical correlation measure is defined and approximated via Bayes' rule, which is then used to allocate resources online in proportion to the inferred degree of source-target correlation. In the experiments, the performance of the proposed algorithm is verified on: 1) sample average approximations of benchmark multiobjective optimization problems under uncertainty and 2) practical multiobjective hyperparameter tuning of deep neural network models. The results show that the proposed algorithm can obtain up to about 73% speedup relative to existing approaches, demonstrating its ability to efficiently tackle real-world multiobjective optimization involving evaluations on large datasets.

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