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1.
Cancer Lett ; 605: 217303, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39413959

RESUMO

Translational initiation in protein synthesis is an important regulatory step in gene expression and its dysregulation may result in diseases such as cancer. Translational control by eIF4E/4E-BP has been well studied and contributes to mTOR signaling in various biological processes. Here, we report a novel translational control axis in the Wnt/ß-catenin signaling pathway in colon tumorigenesis by eIF3a, a Yin-Yang factor in tumorigenesis and prognosis. We show that eIF3a expression is upregulated in human colon cancer tissues, pre-cancerous adenoma polyps, and associates with ß-catenin level and APC mutation in human samples, and that eIF3a overexpression transforms intestinal epithelial cells. We also show that eIF3a expression is regulated by the Wnt/ß-catenin signaling pathway with an active TCF/LEF binding site in its promoter and that eIF3a knockdown inhibits APC mutation-induced spontaneous colon tumorigenesis in APCmin/+ mice. Together, we conclude that eIF3a upregulation in colon cancer is due to APC mutation and it participates in colon tumorigenesis by adding a translational control axis in the Wnt/ß-catenin signaling pathway and that it can serve as a potential target for colon cancer intervention.

2.
Chem Commun (Camb) ; 60(61): 7934-7937, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38984732

RESUMO

A photoinduced EnT-mediated generation of sulfonamidyl radicals has been accomplished using rationally designed iminophenylacetic acid oxime ester reagents under metal-free conditions. This approach offers a mild, regio- and diastereoselective synthesis of N-sulfonyl diamines via diamination of alkenes and (hetero)arenes.

3.
bioRxiv ; 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-38895246

RESUMO

In this study, using RNA-Seq gene expression data and advanced machine learning techniques, we identified distinct gene expression profiles between male and female pancreatic ductal adenocarcinoma (PDAC) patients. Building upon this insight, we developed sex-specific 3-year survival predictive models along with a single comprehensive model. These sex-specific models outperformed the single general model despite the smaller sample sizes. We further refined our models by using the most important features extracted from these initial models. The refined sex-specific predictive models achieved improved accuracies of 92.62% for males and 91.96% for females, respectively, versus an accuracy of 87.84% from the refined comprehensive model, further highlighting the value of sex-specific analysis. Based on these findings, we created Gap-App, a web application that enables the use of individual gene expression profiles combined with sex information for personalized survival predictions. Gap-App, the first online tool aiming to bridge the gap between complex genomic data and clinical application and facilitating more precise and individualized cancer care, marks a significant advancement in personalized prognosis. The study not only underscores the importance of acknowledging sex differences in personalized prognosis, but also sets the stage for the shift from traditional one-size-fits-all to more personalized and targeted medicine. The GAP-App service is freely available at www.gap-app.org .

4.
J Cosmet Dermatol ; 23(10): 3182-3188, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38803042

RESUMO

BACKGROUND: Patients with hypertrophic scarring tend to experience recurrence after treatment, which often occurs in areas of the body with high skin tension. AIMS: To evaluate better treatments aimed at reducing the risk of scar recurrence in areas of high skin tension. METHODS: Patients were randomly divided into the following three treatment groups: botulinum toxin type A (BTA) via dual-plane micro-drop injections, triamcinolone acetonide (TAC) suspension, and CO2 via fractional CO2 laser. Interventions were implemented in all three groups once a month for three consecutive sessions. After the final treatment, scarring was evaluated at 1, 3, 6, 12, and 24 months using the Patient and Observer Scar Assessment Scale (POSAS). RESULTS: The 3-month POSAS score for each scar indicator in the treatment groups was significantly lower than that in the preoperative groups (p < 0.001). The scar score in the TAC group decreased at 3 months and increased thereafter. For other groups, the scar score continually decreased at all time points according to the Patient Scar Assessment Scale. Based on the Observer Scar Assessment Scale, the scar score continuously decreased at all time points in the BTA group; in the TAC group, it decreased at 1 month and increased thereafter; and in the CO2 group, the scar score decreased at 3 months and subsequently stabilized. CONCLUSIONS: All three treatment methods were effective. However, the BTA group experienced a reduced risk of scar recurrence and maintained long-term treatment effects.


Assuntos
Toxinas Botulínicas Tipo A , Cicatriz Hipertrófica , Lasers de Gás , Triancinolona Acetonida , Humanos , Cicatriz Hipertrófica/tratamento farmacológico , Cicatriz Hipertrófica/etiologia , Toxinas Botulínicas Tipo A/administração & dosagem , Toxinas Botulínicas Tipo A/efeitos adversos , Feminino , Adulto , Triancinolona Acetonida/administração & dosagem , Lasers de Gás/uso terapêutico , Masculino , Adulto Jovem , Recidiva , Resultado do Tratamento , Pessoa de Meia-Idade , Glucocorticoides/administração & dosagem , Glucocorticoides/efeitos adversos , Fármacos Neuromusculares/administração & dosagem , Fármacos Neuromusculares/efeitos adversos , Índice de Gravidade de Doença
5.
Zhongguo Fei Ai Za Zhi ; 27(3): 241-244, 2024 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-38590198

RESUMO

With the continuous innovation of genomics, proteomics and molecular biological detection technology, the treatment of non-small cell lung cancer (NSCLC) has changed from traditional chemotherapy to immunotherapy and targeted therapy. Among them, molecular tumor markers targeting tyrosine kinase pathways play more important roles in clinical practice. For advanced NSCLC patients with positive epidermal growth factor receptor (EGFR) mutations, there are many first-line drugs on the market and they could bring significant efficacy, thus completely subverting the treatment pattern of advanced NSCLC. Common mutations of EGFR in Chinese patients are located on exons 19, 20 and 21, of which exons 19 and 21 mutations are the more common types. Besides, there is also a subtype of EGFR mutations, known as EGFR 20 exon insertion (EGFR 20ins) mutation. The authors summarized the treatment of a lung adenocarcinoma patient with EGFR 20ins mutation accepting Furmonertinib mesylate, in order to provide effective references for clinical diagnosis and treatment.
.


Assuntos
Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Indóis , Neoplasias Pulmonares , Piridinas , Pirimidinas , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Receptores ErbB/genética , Mutação , Éxons
6.
J Lipid Res ; 65(4): 100529, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38467328

RESUMO

FASN, the sole cytosolic enzyme responsible for de novo palmitate synthesis in mammalian cells, has been associated with poor prognosis in cancer and shown to cause drug and radiation resistance by upregulating DNA damage repair via suppression of p65 expression. Targeting FASN by repurposing proton pump inhibitors has generated impressive outcomes in triple-negative breast cancer patients. While p65 regulation of DNA damage repair was thought to be due to its suppression of poly(ADP-ribose) polymerase 1 gene transcription, the mechanism of FASN regulation of p65 expression was unknown. In this study, we show that FASN regulates p65 stability by controlling its phosphorylation at Thr254, which recruits the peptidyl-prolyl cis/trans isomerase Pin1 that is known to stabilize many proteins in the nucleus. This regulation is mediated by palmitate, the FASN catalytic product, not by FASN protein per se. This finding of FASN regulation of p65 stability via phosphorylation of Thr254 and isomerization by Pin1 implicates that FASN and its catalytic product palmitate may play an important role in regulating protein stability in general and p65 more specifically.


Assuntos
Ácido Graxo Sintase Tipo I , Peptidilprolil Isomerase de Interação com NIMA , Peptidilprolil Isomerase de Interação com NIMA/metabolismo , Peptidilprolil Isomerase de Interação com NIMA/genética , Humanos , Fosforilação , Estabilidade Proteica , Fator de Transcrição RelA/metabolismo , Isomerismo
7.
J Control Release ; 368: 413-429, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38431093

RESUMO

Exosomes continue to attract interest as a promising nanocarrier drug delivery technology. They are naturally derived nanoscale extracellular vesicles with innate properties well suited to shuttle proteins, lipids, and nucleic acids between cells. Nonetheless, their clinical utility is currently limited by several major challenges, such as their inability to target tumor cells and a high proportion of clearance by the mononuclear phagocyte system (MPS) of the liver and spleen. To overcome these limitations, we developed "Smart Exosomes" that co-display RGD and CD47p110-130 through CD9 engineering (ExoSmart). The resultant ExoSmart demonstrates enhanced binding capacity to αvß3 on pancreatic ductal adenocarcinoma (PDAC) cells, resulting in amplified cellular uptake in in vitro and in vivo models and increased chemotherapeutic efficacies. Simultaneously, ExoSmart significantly reduced liver and spleen clearance of exosomes by inhibiting macrophage phagocytosis via CD47p110-130 interaction with signal regulatory proteins (SIRPα) on macrophages. These studies demonstrate that an engineered exosome drug delivery system increases PDAC therapeutic efficacy by enhancing active PDAC targeting and prolonging circulation times, and their findings hold tremendous translational potential for cancer therapy while providing a concrete foundation for future work utilizing novel peptide-engineered exosome strategies.


Assuntos
Carcinoma Ductal Pancreático , Exossomos , Neoplasias Pancreáticas , Humanos , Exossomos/metabolismo , Antígeno CD47 , Linhagem Celular Tumoral , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia
8.
JMIR Form Res ; 8: e53453, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345857

RESUMO

BACKGROUND: In an aging society such as Japan, where the number of older people continues to increase, providing in-hospital end-of-life care for all deaths, and end-of-life care outside of hospitals, such as at home or in nursing homes, will be difficult. In end-of-life care, monitoring patients is important to understand their condition and predict survival time; this information gives family members and caregivers time to prepare for the end of life. However, with no clear indicators, health care providers must subjectively decide if an older patient is in the end-of-life stage, considering factors such as condition changes and decreased food intake. This complicates decisions for family members, especially during home-based care. OBJECTIVE: The purpose of this preliminary retrospective study was to determine whether and how changes in heart rate variability (HRV) indices estimated from ballistocardiography (BCG) occur before the date of death in terminally ill older patients, and ultimately to predict the date of death from the changepoint. METHODS: This retrospective pilot study assessed the medical records of 15 older patients admitted to a special nursing home between August 2019 and December 2021. Patient characteristics and time-domain HRV indices such as the average normal-to-normal (ANN) interval, SD of the normal-to-normal (SDNN) interval, and root mean square of successive differences (RMSSD) from at least 2 months before the date of death were collected. Overall trends of indices were examined by drawing a restricted cubic spline curve. A repeated measures ANOVA was performed to evaluate changes in the indices over the observation period. To explore more detailed changes in HRV, a piecewise regression analysis was conducted to estimate the changepoint of HRV indices. RESULTS: The 15 patients included 8 men and 7 women with a median age of 93 (IQR 91-96) years. The cubic spline curve showed a gradual decline of indices from approximately 30 days before the patients' deaths. The repeated measures ANOVA showed that when compared with 8 weeks before death, the ratio of the geometric mean of ANN (0.90, 95% CI 0.84-0.98; P=.005) and RMSSD (0.83, 95% CI 0.70-0.99; P=.03) began to decrease 3 weeks before death. The piecewise regression analysis estimated the changepoints for ANN, SDNN, and RMSSD at -34.5 (95% CI -42.5 to -26.5; P<.001), -33.0 (95% CI -40.9 to -25.1; P<.001), and -35.0 (95% CI -42.3 to -27.7; P<.001) days, respectively, before death. CONCLUSIONS: This preliminary study identified the changepoint of HRV indices before death in older patients at end of life. Although few data were examined, our findings indicated that HRV indices from BCG can be useful for monitoring and predicting survival time in older patients at end of life. The study and results suggest the potential for more objective and accurate prognostic tools in predicting end-of-life outcomes.

9.
Regen Biomater ; 11: rbad097, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38173769

RESUMO

The inadequate quantity of hydrogen peroxide (H2O2) in cancer cells promptly results in the constrained success of chemodynamic therapy (CDT). Significant efforts made throughout the years; nevertheless, researchers are still facing the great challenge of designing a CDT agent and securing H2O2 supply within the tumor cell. In this study, taking advantage of H2O2 level maintenance mechanism in cancer cells, a nanozyme-based bimetallic metal-organic frameworks (MOFs) tandem reactor is fabricated to elevate intracellular H2O2 levels, thereby enhancing CDT. In addition, under near-infrared excitation, the upconversion nanoparticles (UCNPs) loaded into the MOFs can perform photocatalysis and generate hydrogen, which increases cellular susceptibility to radicals induced from H2O2, inhibits cancer cell energy, causes DNA damages and induces tumor cell apoptosis, thus improving CDT therapeutic efficacy synergistically. The proposed nanozyme-based bimetallic MOFs-mediated CDT and UCNPs-mediated hydrogen therapy act as combined therapy with high efficacy and low toxicity.

10.
IEEE Trans Med Imaging ; 43(3): 928-939, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37847615

RESUMO

Neurodegenerative disorders usually happen stage-by-stage rather than overnight. Thus, cross-sectional brain imaging genetic methods could be insufficient to identify genetic risk factors. Repeatedly collecting imaging data over time appears to solve the problem. But most existing imaging genetic methods only use longitudinal imaging phenotypes straightforwardly, ignoring the disease progression trajectory which might be a more stable disease signature. In this paper, we propose a novel sparse multi-task mixed-effects longitudinal imaging genetic method (SMMLING). In our model, disease progression fitting and genetic risk factors identification are conducted jointly. Specifically, SMMLING models the disease progression using longitudinal imaging phenotypes, and then associates fitted disease progression with genetic variations. The baseline status and changing rate, i.e., the intercept and slope, of the progression trajectory thus shoulder the responsibility to discover loci of interest, which would have superior and stable performance. To facilitate the interpretation and stability, we employ l2,1 -norm and the fused group lasso (FGL) penalty to identify loci at both the individual level and group level. SMMLING can be solved by an efficient optimization algorithm which is guaranteed to converge to the global optimum. We evaluate SMMLING on synthetic data and real longitudinal neuroimaging genetic data. Both results show that, compared to existing longitudinal methods, SMMLING can not only decrease the modeling error but also identify more accurate and relevant genetic factors. Most risk loci reported by SMMLING are missed by comparison methods, implicating its superiority in genetic risk factors identification. Consequently, SMMLING could be a promising computational method for longitudinal imaging genetics.


Assuntos
Doença de Alzheimer , Humanos , Estudos Transversais , Doença de Alzheimer/genética , Neuroimagem/métodos , Encéfalo/diagnóstico por imagem , Fenótipo , Algoritmos , Progressão da Doença , Fatores de Risco , Imageamento por Ressonância Magnética/métodos
11.
ACS Appl Mater Interfaces ; 16(1): 889-897, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38153800

RESUMO

Achieving effective hydrogen evolution/oxidation reaction (HER/HOR) across a wide pH span is of critical importance in unlocking the full potential of hydrogen energy but remains intrinsically challenging. Here, we engineer the N-coordinated Ir-Mo dual atoms on a carbon matrix by ultrafast high-temperature sintering, creating an efficient bifunctional electrocatalyst for both HER and HOR in both acidic and alkaline electrolytes. The optimized catalyst, Ir-Mo DAC/NC, demonstrates exceptional performance, with a significantly reduced HER overpotential of 11.3 mV at 10 mA/cm2 and a HOR exchange current (i0,m) of 3972 mA/mgIr in acidic conditions, surpassing the performance of Pt/C and Ir/C catalysts. In alkaline conditions, Ir-Mo DAC/NC also outperforms Pt/C, as evidenced by its low HER overpotential of 23 mV at 10 mA/cm2 and a high i0,m of 1308 mA/mgIr. Furthermore, our catalyst exhibits remarkable stability in both acidic and alkaline environments. DFT calculations results reveal that the superior electrochemical performance of Ir-Mo DAC/NC arises from the electronic synergy between Ir and Mo pairs, which regulates the interaction between the intermediates and active sites. These findings present a promising strategy for the development of dual-atom catalysts (DACs), with potential applications in the polymer fuel cells and water electrolyzers.

12.
J Med Chem ; 66(24): 16515-16545, 2023 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-38092421

RESUMO

Survivin, a homodimeric protein and a member of the IAP family, plays a vital function in cell survival and cycle progression by interacting with various proteins and complexes. Its expression is upregulated in cancers but not detectable in normal tissues. Thus, it has been regarded and validated as an ideal cancer target. However, survivin is "undruggable" due to its lack of enzymatic activities or active sites for small molecules to bind/inhibit. Academic and industrial laboratories have explored different strategies to overcome this hurdle over the past two decades, with some compounds advanced into clinical testing. These strategies include inhibiting survivin expression, its interaction with binding partners and homodimerization. Here, we provide comprehensive analyses of these strategies and perspective on different small molecule survivin inhibitors to help drug discovery targeting "undruggable" proteins in general and survivin specifically with a true survivin inhibitor that will prevail in the foreseeable future.


Assuntos
Proteínas Inibidoras de Apoptose , Neoplasias , Humanos , Survivina/metabolismo , Proteínas Inibidoras de Apoptose/metabolismo , Neoplasias/metabolismo , Descoberta de Drogas , Dimerização , Apoptose
13.
Front Plant Sci ; 14: 1206728, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37711306

RESUMO

5-Aminolevulinic acid (ALA), as a new natural plant growth regulator, has been proved to regulate protein phosphatase 2A (PP2A) activity to promote stomatal opening in apple (Malus domestica) leaves. However, the molecular mechanisms underlying remain unclear. Here, we cloned and transformed MdPTPA, MdPP2AC, and MdSnRK2.6 of apple into tobaccos (Nicotiana tabacum) and found that over-expression (OE)-MdPTPA or OE-MdPP2AC promoted stomatal aperture while OE-MdSnRK2.6 induced stomatal closure under normal or drought condition. The Ca2+ and H2O2 levels in the guard cells of OE-MdPTPA and OE-MdPP2AC was decreased but flavonols increased, and the results in OE-SnRK2.6 was contrary. Exogenous ALA stimulated PP2A activity but depressed SnRK2.6 activity in transgenic tobaccos, leading to less Ca2+, H2O2 and more flavonols in guard cells, and consequently stomatal opening. OE-MdPTPA improved stomatal opening and plant growth but impaired drought tolerance, while OE-MdSnRK2.6 improved drought tolerance but depressed the leaf P n. Only OE-MdPP2AC improved stomatal opening, leaf P n, plant growth, as well as drought tolerance. These suggest that the three genes involved in ALA-regulating stomatal movement have their respective unique biological functions. Yeast two-hybrid (Y2H) assays showed that MdPP2AC interacted with MdPTPA or MdSnRK2.6, respectively, but no interaction of MdPTPA with MdSnRK2.6 was found. Yeast three-hybrid (Y3H) assay showed that MdPTPA promoted the interactions between MdPP2AC and MdSnRK2.6. Therefore, we propose a regulatory module of PTPA-PP2AC-SnRK2.6 that may be involved in mediating the ALA-inducing stomatal aperture in green plants.

14.
Biology (Basel) ; 12(7)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37508437

RESUMO

Proline isomerization, the process of interconversion between the cis- and trans-forms of proline, is an important and unique post-translational modification that can affect protein folding and conformations, and ultimately regulate protein functions and biological pathways. Although impactful, the importance and prevalence of proline isomerization as a regulation mechanism in biological systems have not been fully understood or recognized. Aiming to fill gaps and bring new awareness, we attempt to provide a wholistic review on proline isomerization that firstly covers what proline isomerization is and the basic chemistry behind it. In this section, we vividly show that the cause of the unique ability of proline to adopt both cis- and trans-conformations in significant abundance is rooted from the steric hindrance of these two forms being similar, which is different from that in linear residues. We then discuss how proline isomerization was discovered historically followed by an introduction to all three types of proline isomerases and how proline isomerization plays a role in various cellular responses, such as cell cycle regulation, DNA damage repair, T-cell activation, and ion channel gating. We then explore various human diseases that have been linked to the dysregulation of proline isomerization. Finally, we wrap up with the current stage of various inhibitors developed to target proline isomerases as a strategy for therapeutic development.

15.
Entropy (Basel) ; 25(6)2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37372269

RESUMO

Measuring the correlation between belief functions is an important issue in Dempster-Shafer theory. From the perspective of uncertainty, analyzing the correlation may provide a more comprehensive reference for uncertain information processing. However, existing studies about correlation have not combined it with uncertainty. In order to address the problem, this paper proposes a new correlation measure based on belief entropy and relative entropy, named a belief correlation measure. This measure takes into account the influence of information uncertainty on their relevance, which can provide a more comprehensive measure for quantifying the correlation between belief functions. Meanwhile, the belief correlation measure has the mathematical properties of probabilistic consistency, non-negativity, non-degeneracy, boundedness, orthogonality, and symmetry. Furthermore, based on the belief correlation measure, an information fusion method is proposed. It introduces the objective weight and subjective weight to assess the credibility and usability of belief functions, thus providing a more comprehensive measurement for each piece of evidence. Numerical examples and application cases in multi-source data fusion demonstrate that the proposed method is effective.

16.
Cancer Lett ; 567: 216266, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37321532

RESUMO

Drug resistance is a major problem in cancer treatment with traditional or targeted therapeutics. Gemcitabine is approved for several human cancers and the first line treatment for locally advanced or metastatic pancreatic ductal adenocarcinoma (PDAC). However, gemcitabine resistance frequently occurs and is a major problem in successful treatments of these cancers and the mechanism of gemcitabine resistance remains largely unknown. In this study, we identified 65 genes that had reversible methylation changes in their promoters in gemcitabine resistant PDAC cells using whole genome Reduced Representation Bisulfite Sequencing analyses. One of these genes, PDGFD, was further studied in detail for its reversible epigenetic regulation in expression and shown to contribute to gemcitabine resistance in vitro and in vivo via stimulating STAT3 signaling in both autocrine and paracrine manners to upregulate RRM1 expression. Analyses of TCGA datasets showed that PDGFD positively associates with poor outcome of PDAC patients. Together, we conclude that the reversible epigenetic upregulation plays an important role in gemcitabine resistance development and targeting PDGFD signaling alleviates gemcitabine resistance for PDAC treatment.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Gencitabina , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Regulação para Cima , Epigênese Genética , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/patologia , Desmetilação , Ribonucleosídeo Difosfato Redutase/genética , Linfocinas/genética , Linfocinas/metabolismo , Linfocinas/uso terapêutico , Fator de Crescimento Derivado de Plaquetas/genética , Neoplasias Pancreáticas
17.
Int J Mol Sci ; 24(8)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37108784

RESUMO

Chemoresistance is a major health concern affecting cancer patients. Resistance is multifactorial, with one mechanism being the increased expression of ABC transporters (such as MDR1 and MRP1), which are drug efflux transporters capable of preventing intracellular accumulation of drugs and cell death. Our lab showed that the loss of Adenomatous Polyposis Coli (APC) caused an intrinsic resistance to doxorubicin (DOX), potentially through an enhanced tumor-initiating cell (TIC) population and the increased activation of STAT3 mediating the expression of MDR1 in the absence of WNT being activated. Here, in primary mouse mammary tumor cells, the loss of APC decreased the accumulation of DOX while increasing the protein levels of MDR1 and MRP1. We demonstrated decreased APC mRNA and protein levels in breast cancer patients compared with normal tissue. Using patient samples and a panel of human breast cancer cell lines, we found no significant trend between APC and either MDR1 or MRP1. Since the protein expression patterns did not show a correlation between the ABC transporters and the expression of APC, we evaluated the drug transporter activity. In mouse mammary tumor cells, the pharmacological inhibition or genetic silencing of MDR1 or MRP1, respectively, decreased the TIC population and increased DOX-induced apoptosis, supporting the use of ABC transporter inhibitors as therapeutic targets in APC-deficient tumors.


Assuntos
Polipose Adenomatosa do Colo , Neoplasias da Mama , Humanos , Camundongos , Animais , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Morte Celular , Linhagem Celular Tumoral , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo
18.
J Biol Chem ; 299(5): 104658, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36997088

RESUMO

Eukaryotic initiation factor 3d (eIF3d), a known RNA-binding subunit of the eIF3 complex, is a 66 to 68-kDa protein with an RNA-binding motif and a cap-binding domain. Compared with other eIF3 subunits, eIF3d is relatively understudied. However, recent progress in studying eIF3d has revealed a number of intriguing findings on its role in maintaining eIF3 complex integrity, global protein synthesis, and in biological and pathological processes. It has also been reported that eIF3d has noncanonical functions in regulating translation of a subset of mRNAs by binding to 5'-UTRs or interacting with other proteins independent of the eIF3 complex and additional functions in regulating protein stability. The noncanonical regulation of mRNA translation or protein stability may contribute to the role of eIF3d in biological processes such as metabolic stress adaptation and in disease onset and progression including severe acute respiratory syndrome coronavirus 2 infection, tumorigenesis, and acquired immune deficiency syndrome. In this review, we critically evaluate the recent studies on these aspects of eIF3d and assess prospects in understanding the function of eIF3d in regulating protein synthesis and in biological and pathological processes.


Assuntos
Progressão da Doença , Fator de Iniciação 3 em Eucariotos , Biossíntese de Proteínas , Capuzes de RNA , Humanos , COVID-19 , Fator de Iniciação 3 em Eucariotos/metabolismo , Capuzes de RNA/metabolismo , Síndrome da Imunodeficiência Adquirida , Carcinogênese , Regiões 5' não Traduzidas/genética
19.
ACS Appl Mater Interfaces ; 15(8): 10718-10725, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36802467

RESUMO

Single-atom catalysts with a tunable coordination structure have shown grand potential in flexibly altering the selectivity of oxygen reduction reaction (ORR) toward the desired pathway. However, rationally mediating the ORR pathway by modulating the local coordination number of the single-metal sites is still challenging. Herein, we prepare the Nb single-atom catalysts (SACs) with an external-shell oxygen-modulated unsaturated NbN3 site in carbon nitride and the NbN4 site anchored in nitrogen-doped carbon carriers, respectively. Compared with typical NbN4 moieties for 4e- ORR, the as-prepared NbN3 SACs exhibit excellent 2e- ORR activity in 0.1 M KOH, with the onset overpotential close to zero (9 mV) and the H2O2 selectivity above 95%, making it one of the state-of-the-art catalysts in the electrosynthesis of hydrogen peroxide. Density functional theory (DFT) theoretical calculations indicate the unsaturated Nb-N3 moieties and the adjacent oxygen groups optimize the interface bond strength of pivotal intermediates (OOH*) for producing H2O2, thus accelerating the 2e- ORR pathway. Our findings may provide a novel platform for developing SACs with high activity and tunable selectivity.

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