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1.
J Biol Chem ; 299(11): 105351, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37838174

RESUMO

Breast cancer stem cells are mainly responsible for poor prognosis, especially in triple-negative breast cancer (TNBC). In a previous study, we demonstrated that ε-Sarcoglycan (SGCE), a type Ⅰ single-transmembrane protein, is a potential oncogene that promotes TNBC stemness by stabilizing EGFR. Here, we further found that SGCE depletion reduces breast cancer stem cells, partially through inhibiting the transcription of FGF-BP1, a secreted oncoprotein. Mechanistically, we demonstrate that SGCE could interact with the specific protein 1 transcription factor and translocate into the nucleus, which leads to an increase in the transcription of FGF-BP1, and the secreted FBF-BP1 activates FGF-FGFR signaling to promote cancer cell stemness. The novel SGCE-Sp1-FGF-BP1 axis provides novel potential candidate diagnostic markers and therapeutic targets for TNBC.


Assuntos
Células-Tronco Neoplásicas , Sarcoglicanas , Fator de Transcrição Sp1 , Neoplasias de Mama Triplo Negativas , Humanos , Linhagem Celular Tumoral , Proliferação de Células , Células-Tronco Neoplásicas/metabolismo , Sarcoglicanas/metabolismo , Transdução de Sinais , Fator de Transcrição Sp1/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo
2.
Langmuir ; 40(16): 8730-8737, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38616350

RESUMO

An elevated level of blood uric acid (UA) can cause the formation of kidney stones, gout, and other diseases. We recently isolated a few DNA aptamers that can selectively bind to UA. In this work, we investigated the adsorption of a UA aptamer and random sequence DNA onto sodium urate crystals. Both DNA strands adsorbed similarly to urate crystals. In addition, both the UA aptamer and random DNA can inhibit the growth of urate crystals, suggesting a nonspecific adsorption mechanism rather than specific aptamer binding. In the presence of 500 nM DNA, the growth of needle-like sodium urate crystals was inhibited, and the crystals appeared granular after 6 h. To understand the mechanism of DNA adsorption, a few chemicals were added to desorb DNA. DNA bases contributed more to the adsorption than the phosphate backbone. Surfactants induced significant DNA desorption. Finally, DNA could also be adsorbed onto real UA kidney stones. This study provides essential insights into the interactions between DNA oligonucleotides and urate crystals, including the inhibition of growth and interface effects of DNA on sodium urate crystals.

3.
Acta Biochim Biophys Sin (Shanghai) ; 55(9): 1487-1495, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37162264

RESUMO

Angiopoietin-1 (ANG1) is a pro-angiogenic regulator that contributes to the progression of solid tumors by stimulating the proliferation, migration and tube formation of vascular endothelial cells, as well as the renewal and stability of blood vessels. However, the functions and mechanisms of ANG1 in triple-negative breast cancer (TNBC) are unclear. The clinical sample database shows that a higher level of ANG1 in TNBC is associated with poor prognosis compared to non-TNBC. In addition, knockdown of ANG1 inhibits TNBC cell proliferation and induces cell cycle G1 phase arrest and apoptosis. Overexpression of ANG1 promotes tumor growth in nude mice. Mechanistically, ANG1 promotes TNBC by upregulating carboxypeptidase A4 (CPA4) expression. Overall, the ANG1-CPA4 axis can be a therapeutic target for TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Linhagem Celular Tumoral , Neoplasias de Mama Triplo Negativas/metabolismo , Angiopoietina-1/genética , Angiopoietina-1/metabolismo , Camundongos Nus , Células Endoteliais/metabolismo , Proliferação de Células/genética , Carboxipeptidases/genética , Carboxipeptidases/metabolismo , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética
4.
J Immunol ; 205(7): 1752-1762, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32868411

RESUMO

P2X7 receptor (P2X7R) is highly expressed on immune cells, triggering the release of cytokines and regulating autoimmune responses. To investigate P2X7R surface expression on T helper (Th) 1, Th17, and regulatory T (Treg) cells in patients with systemic lupus erythematosus (SLE) or rheumatoid arthritis (RA) and correlations with disease activity, 29 SLE and 29 RA patients and 18 healthy controls (HCs) were enrolled. We showed that SLE and RA patients had significantly higher levels of plasma cytokines (IFN-γ, IL-1ß, IL-6, IL-17A, and IL-23), frequencies of Th1 and Th17 cells, and expression of P2X7R on Th1 and Th17 than HCs, and the Th17/Treg ratio was significantly increased, whereas Treg cell levels were significantly decreased. The Ca2+ influx increase following BzATP stimulation was significantly higher in CD4+PBMCs from SLE and RA patients than in HCs. Blood levels of shed P2X7R were increased in SLE and RA patients. Furthermore, 28-joint Disease Activity Score and SLE Disease Activity Index score showed negative correlations with Treg cell levels and positive correlations with Th17/Treg ratio and Th17 cell P2X7R expression. Interestingly, Th17 cell P2X7R expression was closely correlated with IL-1ß, C-reactive protein, the erythrocyte sedimentation rate, anticyclic citrullinated peptide Abs, albumin, and C4. These data indicate that increased Th17 cell P2X7R expression is functionally and positively related to disease activity and some inflammatory mediators in SLE and RA patients, and P2X7R could be critical in promoting the Th17 immune response and contributing to the complex pathogenesis of SLE and RA.


Assuntos
Artrite Reumatoide/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Receptores Purinérgicos P2X7/metabolismo , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th17/imunologia , Doença Aguda , Adulto , Idoso , Progressão da Doença , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Receptores Purinérgicos P2X7/genética
5.
Anal Bioanal Chem ; 414(22): 6581-6590, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35831535

RESUMO

Based on a Pb2+-specific 8-17 DNAzyme-induced catalytic hairpin assembly (CHA), a simple signal-on fluorescence strategy for lead ion detection was established. 8-17 DNAzyme was used as the recognition element of Pb2+, which catalyzed the cleavage of the RNA base embedded in the DNA substrate strand, while releasing part of the substrate strand (S') as CHA initiator. And two hairpin probes (H1 and H2-FQ) were designed according to the sequence of S' for CHA, in which H2-FQ was labeled with the fluorophore FAM and quencher BHQ-1 as fluorescent "molecular switch" based on fluorescence resonance energy transfer (FRET). In the presence of Pb2+, the CHA reaction was triggered to form a large number of H1-H2 complexes, enabling enzyme-free isothermal amplification and a signal-on fluorescence strategy. In the concentration range of 0.5-1000 nM, the fluorescence signal increases with the increase of Pb2+ concentration. The quantitative detection limit of Pb2+ by this method is 0.5 nM, which has better detection performance compared with the FQ-labeled 8-17 DNAzyme method. The established biosensor exhibits good specificity and can be effectively used for the detection of Pb2+ in real samples of river water and grass carp. Through ingenious nucleic acid sequence design, DNAzyme and CHA reactions are integrated to realize the enzyme-free isothermal amplifications and sensitive detection of Pb2+, which holds potential versatility in food supervision and environmental monitoring.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Técnicas Biossensoriais/métodos , Catálise , DNA/química , DNA Catalítico/química , Chumbo , Limite de Detecção
6.
J Biol Chem ; 294(47): 17837-17847, 2019 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-31624151

RESUMO

The Krüppel-like factor 5 (KLF5) transcription factor is highly expressed in basal type breast cancer and promotes breast cancer cell proliferation, survival, migration, and tumorigenesis. KLF5 protein stability is regulated by ubiquitination. In this study, ubiquitin-specific protease 3 (USP3) was identified as a new KLF5 deubiquitinase by genome-wide siRNA library screening. We demonstrated that USP3 interacts with KLF5 and stabilizes KLF5 via deubiquitination. USP3 knockdown inhibits breast cancer cell proliferation in vitro and tumorigenesis in vivo, which can be partially rescued by ectopic expression of KLF5. Furthermore, we observed a positive correlation between USP3 and KLF5 protein expression levels in human breast cancer samples. These findings suggest that USP3 is a new KLF5 deubiquitinase and that USP3 may represent a potential therapeutic target for breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Fatores de Transcrição Kruppel-Like/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Ubiquitinação , Animais , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Células HEK293 , Humanos , Camundongos Nus , Ligação Proteica , Estabilidade Proteica , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
7.
Appl Microbiol Biotechnol ; 104(5): 2017-2028, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31930453

RESUMO

This paper focuses on the production of a high-affinity monoclonal antibody (mAb) that can efficiently detect and block purinergic ligand-gated ion channel 7 receptor (P2X7R). To achieve this goal, the extracellular domain of human P2X7R, P2X7R-ECD, was used as an immunogen for BALB/c mice, inducing them to produce spleen lymphocytes that were subsequently fused with myeloma cells. Screening of the resultant hybridoma clones resulted in the selection of one stable positive clone that produced a qualified mAb, named 4B3A4. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis demonstrated that the purity of the purified 4B3A4 mAb was above 85%, with prominent bands corresponding to molecular weights of 55 kDa (heavy chain) and 25 kDa (light chain), and the BCA assay showed that the concentration of the purified 4B3A4 mAb was 0.3 mg/mL. Western blot analysis revealed that the 4B3A4 mAb could specifically recognize and bind both P2X7R-ECD and the full-length P2X7R protein. Laser scanning confocal microscopy (LSCM) revealed that the 4B3A4 mAb specifically bound to P2X7R on the membrane of human peripheral blood mononuclear cells (PBMCs). P2X7R expression was significantly different between healthy individuals and people with certain cancers as determined by flow cytometry (FCM). In addition, the 4B3A4 mAb significantly reduced ATP-stimulated Ca2+ entry and YO-PRO-1 uptake, which indicated that the 4B3A4 mAb effectively blocked P2X7R activity. These data indicate that the 4B3A4 mAb can be further used as not only an antibody to detect cell surface P2X7R but also as a therapeutic antibody to target P2X7R-related signaling pathways.


Assuntos
Anticorpos Monoclonais/imunologia , Receptores Purinérgicos P2X7/imunologia , Animais , Anticorpos Monoclonais/química , Especificidade de Anticorpos , Benzoxazóis/metabolismo , Cálcio/metabolismo , Membrana Celular/metabolismo , Células Cultivadas , Feminino , Humanos , Imunoglobulina G/química , Imunoglobulina G/imunologia , Leucócitos Mononucleares/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Peso Molecular , Domínios Proteicos , Compostos de Quinolínio/metabolismo , Receptores Purinérgicos P2X7/química
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124643, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-38901233

RESUMO

Herein, two simple fluorescent signal-on sensing strategies for detecting lead ions (Pb2+) were established based on structure-switching aptamer probes and exonuclease-assisted signal amplification strategies. Two hairpin-structure fluorescent probes with blunt-ended stem arms were designed by extending the base sequence of Pb2+ aptamer (PS2.M) and labelling the probes with FAM (in probe 1) and 2-aminopurine (2-AP) (in probe 2), respectively. In method 1, graphene oxide (GO) was added to adsorb probe 1 and quench the fluorescence emission of FAM to achieve low fluorescent background. In method 2, fluorescent 2-AP molecule inserted into the double-stranded DNA of probe 2 was quenched as a result of base stacking interactions, leading to a simplified, quencher-free approach. The addition of Pb2+ can induce the probes to transform into G-quadruplex structures, exposing single DNA strands at the 3' end (the extended sequences). This exposure enables the activation of exonuclease I (Exo I) on the probes, leading to the cleavage effect and subsequent release of free bases and fluorophores, thereby resulting in amplified fluorescence signals. The two proposed methods exhibit good specificity and sensitivity, with detection limits of 0.327 nM and 0.049 nM Pb2+ for method 1 and method 2, respectively, and have been successfully applied to detect Pb2+ in river water and fish samples. Both detection methods employ the structure-switching aptamer probes and can be completed in two or three steps without the need for complex analytical instruments. Therefore, they have a broad prospect in the sensitive and simple detection of lead ion contamination in food and environmental samples.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Exodesoxirribonucleases , Corantes Fluorescentes , Chumbo , Limite de Detecção , Espectrometria de Fluorescência , Chumbo/análise , Aptâmeros de Nucleotídeos/química , Exodesoxirribonucleases/metabolismo , Exodesoxirribonucleases/química , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos , Técnicas Biossensoriais/métodos , Sondas de DNA/química , Poluentes Químicos da Água/análise , Animais , Íons/análise , Grafite/química
9.
Biosens Bioelectron ; 263: 116594, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39084043

RESUMO

Adsorption of DNA fluorescent probes on GO-Fe3O4 is a promising strategy for establishing fluorescent bioassays, often using magnetic separation or fluorescence quenching to generate signals. However, there is a lack of systematic understanding of ssDNA-regulated changes in the enzyme-mimetic activity of GO-Fe3O4, and the accuracy of the results of single-mode fluorescence analysis is susceptible to environmental interference. These limit the rational design and scope of application of the methods. Herein, the force and the catalytic mechanism of ssDNA/GO-Fe3O4 interactions were explored in detail. On this basis, a ratiometric fluorescence/colorimetric dual-modal analysis platform was constructed based on the superparamagnetism and DNA controllable peroxidase-like activity of GO-Fe3O4. The ratiometric fluorescent signal was generated by combining 7-amino-4-methyl-3-coumarinylacetic acid (AMCA) labeled aptamer (AMCA-aptamer) with AT hairpin-synthesized copper nanoparticles, which has built-in correction and resistance to environmental interference. The aptamer-modulated peroxidase-like activity of GO-Fe3O4 generated the colorimetric signal. Two signals correct each other to further enhance the reliability of the results. The analytical platform performed satisfactorily for AFB1 detection in the range of 0.1-150 µg/L, and was successfully applied to real samples (peanut, milk powder, and wheat flour). With the support of ImageJ software, quantitative detection was achieved by RGB channel analysis for real-color images, which provides a potential pathway for the rapid detection of food safety.


Assuntos
Aflatoxina B1 , Técnicas Biossensoriais , Colorimetria , Contaminação de Alimentos , Técnicas Biossensoriais/métodos , Colorimetria/métodos , Contaminação de Alimentos/análise , Aflatoxina B1/análise , Aflatoxina B1/química , Aptâmeros de Nucleotídeos/química , Corantes Fluorescentes/química , Limite de Detecção , Análise de Alimentos/métodos , Grafite/química , DNA de Cadeia Simples/química , Espectrometria de Fluorescência/métodos
10.
Biosens Bioelectron ; 251: 116089, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38354496

RESUMO

Benefiting from specific target recognition and trans-cleavage capabilities, the CRISPR/Cas12a system has great application prospects in the design of highly sensitive and rapid fluorescence biosensors. The CRISPR/Cas12a-based fluorophore-quencher molecular beacons exhibit single-color emission and are easily exposed to interference from environmental factors. Herein, we design a CRISPR/Cas12a-derived ratiometric fluorescence sensor for Pb2+ detection based on embedded carbon dots@zeolitic imidazolate framework-8 (CDs@ZIF-8) composites and DNAzyme. The functions of ZIF-8 about encapsulating red emissive CDs in the inner cavity and adsorbing DNA on the outer surface are integrated to establish dual fluorescence signals, thereby reducing the possibility of interference and improving sensing accuracy. The presence of Pb2+ is converted into the change of activator by the GR5 DNAzyme to activate the CRISPR/Cas12a system, which provides signal amplification through multiple turnovers of side branch cutting, achieving highly sensitive detection of Pb2+ with a low detection limit of 18 pM. This method has the advantages of simplicity, universality, and excellent quantitative ability, and has broad prospects in sensing applications.


Assuntos
Técnicas Biossensoriais , Radioisótopos de Carbono , DNA Catalítico , Sistemas CRISPR-Cas , Chumbo
11.
MedComm (2020) ; 5(8): e665, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39049965

RESUMO

Colorectal cancer (CRC) is one of the most common malignancies worldwide. In the clinical realm, platinum-based drugs hold an important role in the chemotherapy of CRC. Nonetheless, a multitude of patients, due to tumor protein 53 (TP53) gene mutations, experience the emergence of drug resistance. This phenomenon gravely impairs the effectiveness of therapy and long-term prognosis. Gallium, a metallic element akin to iron, has been reported that has the potential to be used to develop new metal anticancer drugs. In this study, we screened and established the gallium complex K6 as a potent antitumor agent in both in vitro and in vivo. K6 exhibited superior efficacy in impeding the growth, proliferation, and viability of CRC cells carrying TP53 mutations compared to oxaliplatin. Mechanistically, K6 escalated reactive oxygen species levels and led deoxyribonucleic acid (DNA) damage. Furthermore, K6 effectively suppressed the phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB)/glycogen synthase kinase 3 beta (GSK3ß) pathway, leading to the degradation of its downstream effectors myelocytomatosis (c-Myc) and Krueppel-like factor 5 (KLF5). Conversely, K6 diminished the protein expression of WW domain-containing protein 1 (WWP1) while activating phosphatase and tensin homolog (PTEN) through c-Myc degradation. This dual action further demonstrated the potential of K6 as a promising therapeutic compound for TP53-mutated CRC.

12.
Biomed Pharmacother ; 177: 116972, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38906024

RESUMO

Breast cancer is one of the most prevalent malignancies affecting women worldwide, underscoring the urgent need for more effective and specific treatments. Proteolysis-targeting chimeras (PROTACs) have emerged as a promising strategy to develop new lead compounds by selectively targeting oncoproteins for degradation. In this study, we designed, synthesized and evaluated a CRBN-based PROTAC, L055, which targets CDK9. Our findings demonstrate that L055 effectively inhibits the proliferation, induces cell cycle arrest, and decreases the survival of ERα-positive breast cancer cells in vitro. L055 specifically binds to CDK9, facilitating its degradation via the CRBN-dependent proteasomal pathway. Additionally, L055 suppressed the growth of organoids and tumors derived from T47D and MCF7 cells in nude mice. Thus, L055 represents a potential novel therapeutic agent for ERα-positive breast cancer and potentially other malignancies.


Assuntos
Neoplasias da Mama , Proliferação de Células , Quinase 9 Dependente de Ciclina , Receptor alfa de Estrogênio , Camundongos Nus , Proteólise , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Feminino , Animais , Receptor alfa de Estrogênio/metabolismo , Proteólise/efeitos dos fármacos , Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Quinase 9 Dependente de Ciclina/metabolismo , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Células MCF-7 , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Endogâmicos BALB C , Camundongos , Antineoplásicos/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
13.
iScience ; 27(3): 109232, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38425843

RESUMO

"Candidatus Liberibacter spp." are insect-vectored, fastidious, and vascular-limited phytopathogens. They are the presumptive causal agents of potato zebra chip, tomato vein clearing, and the devastating citrus greening disease worldwide. There is an urgent need to develop new strategies to control them. In this study, we characterized a dual-specificity serine/tyrosine phosphatase (STP) that is well conserved among thirty-three geographically diverse "Candidatus Liberibacter spp." and strains that infect multiple Solanaceaea and citrus spp. The STP is expressed in infected plant tissues, localized at the plant cytosol and plasma membrane, and interferes with plant cell death responses. We employed an in silico target-based molecular modeling and ligand screen to identify two small molecules with high binding affinity to STP. Efficacy studies demonstrated that the two molecules can inhibit "Candidatus Liberibacter spp." but not unrelated pathogens and confer plant disease tolerance. The inhibitors and strategies are promising means to control "Candidatus Liberibacter spp."

14.
Cell Death Dis ; 15(1): 86, 2024 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267403

RESUMO

The NLRP3 inflammasome plays an important role in protecting the host from infection and aseptic inflammation, and its regulatory mechanism is not completely understood. Dysregulation of NLRP3 can cause diverse inflammatory diseases. HECTD3 is a E3 ubiquitin ligase of the HECT family that has been reported to participate in autoimmune and infectious diseases. However, the relationship between HECTD3 and the NLRP3 inflammasome has not been well studied. Herein, we show that HECTD3 blocks the interaction between NEK7 and NLRP3 to inhibit NLRP3 inflammasome assembly and activation. In BMDMs, Hectd3 deficiency promotes the assembly and activation of NLRP3 inflammasome and the secretion of IL-1ß, while the overexpression of HECTD3 inhibits these processes. Unexpectedly, HECTD3 functions in an E3 activity independent manner. Mechanically, the DOC domain of HECTD3 interacts with NACHT/LRR domain of NLRP3, which blocks NLRP3-NEK7 interaction and NLRP3 oligomerization. Furthermore, HECTD3 inhibits monosodium urate crystals (MSU)-induced gouty arthritis, a NLRP3-related disease. Thus, we reveal a novel regulatory mechanism of NLRP3 by HECTD3 and suggest HECTD3 could be a potential therapeutic target for NLRP3-dependent pathologies.


Assuntos
Artrite Gotosa , Inflamassomos , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Inflamação , Interleucina-1beta , Quinases Relacionadas a NIMA/genética
15.
Oncogene ; 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164524

RESUMO

Interest in the use of proteolysis-targeting chimeras (PROTACs) in cancer therapy has increased in recent years. Targeting bromodomain and extra terminal domain (BET) proteins, especially bromodomain-containing protein 4 (BRD4), has shown inhibitory effects on basal-like breast cancer (BLBC). However, the bioavailability of BRD4 PROTACs is restricted by their non-selective biodegradability and low tumor-targeting ability. We demonstrated that 6b (BRD4 PROTAC) suppresses BLBC cell growth by targeting BRD4, but not BRD2 and BRD3, for cereblon (CRBN)-mediated ubiquitination and proteasomal degradation. Compound 6b also inhibited expression of Krüppel-like factor 5 (KLF5) transcription factor, a key oncoprotein in BLBC, controlled by BRD4-mediated super-enhancers. Moreover, 6b inhibited HCC1806 tumor growth in a xenograft mouse model. The combination of 6b and KLF5 inhibitors showed additive effects on BLBC. These results suggest that BRD4-specific PROTAC can effectively inhibit BLBC by downregulating KLF5, and that 6b has potential as a novel therapeutic drug for BLBC.

16.
Food Chem ; 412: 135551, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-36738532

RESUMO

Understanding the residues and degradation of organophosphorus pesticides (OPs) in crops has attracted increasing attention. Herein, we designed a sensitive fluorescence immunoassay (FIA) by employing nanobody-linked alkaline phosphatase (Nb-ALP) and gold nanoclusters anchored manganese dioxide (AuNCs-MnO2) composite. In immunoassay protocol, Nb-ALP is used to competitively recognize the coating antigen and pesticide. After competitive immunoreaction, alkaline phosphatase catalyzes l-ascorbic acid-2-phosphate to produce ascorbic acid that can trigger the decomposition of the AuNCs-MnO2 composite, regulating the fluorescence response. As a proof-of-concept, fenitrothion (FNT) is chosen as the target analyte. As a result, the developed FIA exhibits high detection sensitivity (IC10 = 5.78 pg/mL), which is about 56-times higher than that of the conventional enzyme-linked immunosorbent assay. The developed FIA has been successfully applied for precisely monitoring the degradation of FNT in Chinese cabbage with excellent anti-interference ability and reproducibility, paving the way for the determination of pesticide residues in real food samples.


Assuntos
Brassica , Praguicidas , Óxidos/química , Compostos de Manganês , Fenitrotion , Ouro/química , Fosfatase Alcalina , Reprodutibilidade dos Testes , Compostos Organofosforados , Imunoensaio
17.
Int J Biol Sci ; 19(6): 1861-1874, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063424

RESUMO

Ephrin type-A receptor 2 (EphA2) is a member of the tyrosine receptor kinases, a family of membrane proteins recognized as potential anticancer targets. EphA2 highly expressed in a variety of human cancers, playing roles in proliferation, migration, and invasion. However, whether and how EphA2 regulates basal-like breast cancer (BLBC) cell stemness and chemoresistance has not been revealed. Here, KLF5 was proven to be a direct transcription factor for EphA2 in BLBC cells, and its expression was positively correlated in clinical samples from breast cancer patients. The inflammatory factor TNF-α could promote BLBC cell stemness partially by activating the KLF5-EphA2 axis. Moreover, phosphorylation of EphA2 at S897 (EphA2 pS897) induced by TNF-α and PTX/DDP contributes to chemoresistance of BLBC. Furthermore, the EphA2 inhibitor ALW-II-41-27 could effectively reduce EphA2 pS897 and tumor cell stemness in vitro and significantly enhance the sensitivity of xenografts to the chemotherapeutic drugs PTX and DDP in vivo. Clinically, tumor samples from breast patients with less response to neoadjuvant chemotherapy showed a high level of EphA2 pS897 expression. In conclusion, KLF5-EphA2 promotes stemness and drug resistance in BLBC and could be a potential target for the treatment of BLBC.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos/genética , Fatores de Transcrição Kruppel-Like/genética , Fosforilação , Fator de Necrose Tumoral alfa
18.
Elife ; 122023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37787041

RESUMO

Anti-tumor drug resistance is a challenge for human triple-negative breast cancer (TNBC) treatment. Our previous work demonstrated that TNFAIP2 activates RAC1 to promote TNBC cell proliferation and migration. However, the mechanism by which TNFAIP2 activates RAC1 is unknown. In this study, we found that TNFAIP2 interacts with IQGAP1 and Integrin ß4. Integrin ß4 activates RAC1 through TNFAIP2 and IQGAP1 and confers DNA damage-related drug resistance in TNBC. These results indicate that the Integrin ß4/TNFAIP2/IQGAP1/RAC1 axis provides potential therapeutic targets to overcome DNA damage-related drug resistance in TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Integrina beta4/genética , Integrina beta4/metabolismo , Linhagem Celular Tumoral , Resistência a Medicamentos , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismo , Citocinas
19.
Asia Pac J Oncol Nurs ; 10(5): 100221, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37123032

RESUMO

Objective: This study explores the impact of posttraumatic stress (PTS) on posttraumatic growth (PTG) and verifies the mediating effect of spirituality among patients with cancer. Methods: This study used a cross-sectional correlational design. This study surveyed 141 hospitalized patients over 20 years of age diagnosed with cancer. Participants were recruited by convenience sampling from a regional hospital in Taiwan. Data were collected from January to April 2021. Measurements included sociodemographic and disease-related information and data from the following self-report questionnaires: Posttraumatic Stress Reaction Index-Short Form, Posttraumatic Growth Inventory, and Spiritual Health Scale-Short Form. Structural equation modeling and bootstrapping were used to analyze the mediating effect of spiritual health on PTS and PTG. Results: PTS and spirituality were negatively correlated, spirituality, and PTG were positively correlated, and PTS had no correlation with PTG. Spirituality fully presented a mediating role between PTS and PTG. Conclusions: Patients' spirituality should be regarded as an important variable that can impact stress appraisal and improve the patient's PTG when a diagnosis of cancer is received. Assessing spiritual health at regular intervals and integrating spiritual care with clinical care could decrease PTS and improve PTG for patients with cancer.

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 298: 122787, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37150075

RESUMO

Heavy metal pollution can pose a threat to food safety and human health, and accurate quantification of heavy metal ions is a vital requirement. Emerging DNA nanostructures-based biosensors offer attractive tools toward ultra-sensitive or rapid analysis of heavy metal ions. However, the problems including complex design, severe reaction conditions and undesirable reliability are inevitable obstacle in advancing their extension and application. Herein, a ratiometric fluorescent platform was established for monitoring lead ion (Pb2+) in food based on dual Förster resonance energy transfer (FRET) and RNA cleavage-inhibited self-assembly of three-arm branched junction (TBJ). GR-5 DNAzyme was employed for Pb2+ recognition, and enzyme-free amplification technique catalytic hairpin assembly (CHA) served to form FRET probes-carried TBJ. The substrate strand (S) of DNAzyme triggered the generation of CHA-TBJ, and Pb2+-responsive cleavage of S hindered the assembly of CHA-TBJ, causing opposite changes in the FRET states of FAM/BHQ1 and ROX/BHQ2 pairs. The fluorescence responses were recorded through synchronous fluorescence spectrometry to indicate Pb2+ concentration, allowing sensitive and reliable identification of Pb2+ in the linear range of 0.05-5 ng mL-1 with the detection limit of 0.03 ng mL-1. The Pb2+ detection can be achieved under conventional reaction conditions, simple mixing procedures and one-step measurement operation. The approach can afford excellent specificity for Pb2+ against competing metal ions, and can be applied to analyze Pb2+ in tea samples with satisfactory results. This facile fluorescence platform shows a capable method for Pb2+ detection, and provides new avenue in the development of ratiometric approaches and DNAzyme strategies for monitoring heavy metal pollution, facilitating the transformation of DNAzyme-based biosensors for food safety control.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Humanos , DNA Catalítico/química , Chumbo , Clivagem do RNA , Reprodutibilidade dos Testes , Íons , Técnicas Biossensoriais/métodos , Limite de Detecção
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