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1.
Nature ; 619(7968): 112-121, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37316654

RESUMEN

Human genomics is witnessing an ongoing paradigm shift from a single reference sequence to a pangenome form, but populations of Asian ancestry are underrepresented. Here we present data from the first phase of the Chinese Pangenome Consortium, including a collection of 116 high-quality and haplotype-phased de novo assemblies based on 58 core samples representing 36 minority Chinese ethnic groups. With an average 30.65× high-fidelity long-read sequence coverage, an average contiguity N50 of more than 35.63 megabases and an average total size of 3.01 gigabases, the CPC core assemblies add 189 million base pairs of euchromatic polymorphic sequences and 1,367 protein-coding gene duplications to GRCh38. We identified 15.9 million small variants and 78,072 structural variants, of which 5.9 million small variants and 34,223 structural variants were not reported in a recently released pangenome reference1. The Chinese Pangenome Consortium data demonstrate a remarkable increase in the discovery of novel and missing sequences when individuals are included from underrepresented minority ethnic groups. The missing reference sequences were enriched with archaic-derived alleles and genes that confer essential functions related to keratinization, response to ultraviolet radiation, DNA repair, immunological responses and lifespan, implying great potential for shedding new light on human evolution and recovering missing heritability in complex disease mapping.


Asunto(s)
Pueblos del Este de Asia , Etnicidad , Variación Genética , Genoma Humano , Genética Humana , Grupos Minoritarios , Humanos , Pueblos del Este de Asia/clasificación , Pueblos del Este de Asia/genética , Etnicidad/genética , Genoma Humano/genética , Análisis de Secuencia de ADN , Rayos Ultravioleta , Genética Humana/normas , Minorías Étnicas y Raciales , Estándares de Referencia , Haplotipos/genética , Eucromatina/genética , Alelos , Reparación del ADN/genética , Queratinas/genética , Queratinas/metabolismo , Longevidad/genética , Inmunidad/genética
2.
Brief Bioinform ; 25(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38385872

RESUMEN

Drug discovery and development constitute a laborious and costly undertaking. The success of a drug hinges not only good efficacy but also acceptable absorption, distribution, metabolism, elimination, and toxicity (ADMET) properties. Overall, up to 50% of drug development failures have been contributed from undesirable ADMET profiles. As a multiple parameter objective, the optimization of the ADMET properties is extremely challenging owing to the vast chemical space and limited human expert knowledge. In this study, a freely available platform called Chemical Molecular Optimization, Representation and Translation (ChemMORT) is developed for the optimization of multiple ADMET endpoints without the loss of potency (https://cadd.nscc-tj.cn/deploy/chemmort/). ChemMORT contains three modules: Simplified Molecular Input Line Entry System (SMILES) Encoder, Descriptor Decoder and Molecular Optimizer. The SMILES Encoder can generate the molecular representation with a 512-dimensional vector, and the Descriptor Decoder is able to translate the above representation to the corresponding molecular structure with high accuracy. Based on reversible molecular representation and particle swarm optimization strategy, the Molecular Optimizer can be used to effectively optimize undesirable ADMET properties without the loss of bioactivity, which essentially accomplishes the design of inverse QSAR. The constrained multi-objective optimization of the poly (ADP-ribose) polymerase-1 inhibitor is provided as the case to explore the utility of ChemMORT.


Asunto(s)
Aprendizaje Profundo , Humanos , Desarrollo de Medicamentos , Descubrimiento de Drogas , Inhibidores de Poli(ADP-Ribosa) Polimerasas
3.
Nucleic Acids Res ; 52(W1): W439-W449, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38783035

RESUMEN

High-throughput screening rapidly tests an extensive array of chemical compounds to identify hit compounds for specific biological targets in drug discovery. However, false-positive results disrupt hit compound screening, leading to wastage of time and resources. To address this, we propose ChemFH, an integrated online platform facilitating rapid virtual evaluation of potential false positives, including colloidal aggregators, spectroscopic interference compounds, firefly luciferase inhibitors, chemical reactive compounds, promiscuous compounds, and other assay interferences. By leveraging a dataset containing 823 391 compounds, we constructed high-quality prediction models using multi-task directed message-passing network (DMPNN) architectures combining uncertainty estimation, yielding an average AUC value of 0.91. Furthermore, ChemFH incorporated 1441 representative alert substructures derived from the collected data and ten commonly used frequent hitter screening rules. ChemFH was validated with an external set of 75 compounds. Subsequently, the virtual screening capability of ChemFH was successfully confirmed through its application to five virtual screening libraries. Furthermore, ChemFH underwent additional validation on two natural products and FDA-approved drugs, yielding reliable and accurate results. ChemFH is a comprehensive, reliable, and computationally efficient screening pipeline that facilitates the identification of true positive results in assays, contributing to enhanced efficiency and success rates in drug discovery. ChemFH is freely available via https://chemfh.scbdd.com/.


Asunto(s)
Descubrimiento de Drogas , Ensayos Analíticos de Alto Rendimiento , Programas Informáticos , Descubrimiento de Drogas/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Evaluación Preclínica de Medicamentos/métodos , Reacciones Falso Positivas , Bibliotecas de Moléculas Pequeñas/farmacología , Bibliotecas de Moléculas Pequeñas/química , Humanos
4.
Plant J ; 119(1): 478-489, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38659310

RESUMEN

The Q transcription factor plays important roles in improving multiple wheat domestication traits such as spike architecture, threshability and rachis fragility. However, whether and how it regulates abiotic stress adaptation remain unclear. We found that the transcriptional expression of Q can be induced by NaCl and abscisic acid treatments. Using the q mutants generated by CRISPR/Cas9 and Q overexpression transgenic lines, we showed that the domesticated Q gene causes a penalty in wheat salt tolerance. Then, we demonstrated that Q directly represses the transcription of TaSOS1-3B and reactive oxygen species (ROS) scavenging genes to regulate Na+ and ROS homeostasis in wheat. Furthermore, we showed that wheat salt tolerance protein TaWD40 interacts with Q to competitively interfere with the interaction between Q and the transcriptional co-repressor TaTPL. Taken together, our findings reveal that Q directly represses the expression of TaSOS1 and some ROS scavenging genes, thus causing a harmful effect on wheat salt tolerance.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Plantas Modificadas Genéticamente , Especies Reactivas de Oxígeno , Tolerancia a la Sal , Triticum , Triticum/genética , Triticum/fisiología , Triticum/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Tolerancia a la Sal/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacología
5.
Brief Bioinform ; 25(1)2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-38084920

RESUMEN

Protein-ligand binding affinity (PLBA) prediction is the fundamental task in drug discovery. Recently, various deep learning-based models predict binding affinity by incorporating the three-dimensional (3D) structure of protein-ligand complexes as input and achieving astounding progress. However, due to the scarcity of high-quality training data, the generalization ability of current models is still limited. Although there is a vast amount of affinity data available in large-scale databases such as ChEMBL, issues such as inconsistent affinity measurement labels (i.e. IC50, Ki, Kd), different experimental conditions, and the lack of available 3D binding structures complicate the development of high-precision affinity prediction models using these data. To address these issues, we (i) propose Multi-task Bioassay Pre-training (MBP), a pre-training framework for structure-based PLBA prediction; (ii) construct a pre-training dataset called ChEMBL-Dock with more than 300k experimentally measured affinity labels and about 2.8M docked 3D structures. By introducing multi-task pre-training to treat the prediction of different affinity labels as different tasks and classifying relative rankings between samples from the same bioassay, MBP learns robust and transferrable structural knowledge from our new ChEMBL-Dock dataset with varied and noisy labels. Experiments substantiate the capability of MBP on the structure-based PLBA prediction task. To the best of our knowledge, MBP is the first affinity pre-training model and shows great potential for future development. MBP web-server is now available for free at: https://huggingface.co/spaces/jiaxianustc/mbp.


Asunto(s)
Descubrimiento de Drogas , Proteínas , Ligandos , Proteínas/química , Unión Proteica , Marcadores de Afinidad
6.
Drug Resist Updat ; 72: 101033, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38157648

RESUMEN

Recently, radioresistance has become a major obstacle in the radiotherapy of cervical cancer. To demonstrate enhanced radiosensitization against radioresistant cervical cancer, radioresistant cervical cancer cell line was developed and the mechanism of radioresistance was explored. Due to the overexpression of (death receptor 5, DR5) in cervical cancer, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-overexpressed cervical cancer cell membrane-camouflaged Cu2-xSe nanomedicine (CCMT) was designed. Since the CCMT was encapsulated with TRAIL-modified cell membrane, it represented high target to cervical cancer cell and immune evasion. Furthermore, Cu2-xSe had the ability to scavenge glutathione (GSH) and produce ·OH with excess H2O2 in the tumor microenvironment. The presence of CCMT combined with radiation therapy could effectively increase the 1O2 produced by X-rays. In vitro and in vivo studies elaborated that CCMT exhibited excellent radiosensitization properties to reverse radiotolerance by scavenging GSH and promoting DNA damage, apoptosis, mitochondrial membrane potential damage and metabolic disruption. Collectively, this study suggested that the development of TRAIL-overexpressed cell membrane-camouflaged Cu2-xSe nanomedicine could advance future cervical cancer treatment and minimize the disadvantages associated with radiation treatment.


Asunto(s)
Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/radioterapia , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología , Peróxido de Hidrógeno , Ligandos , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Ligando Inductor de Apoptosis Relacionado con TNF/farmacología , Apoptosis , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo , Línea Celular Tumoral , Microambiente Tumoral
7.
Biochem Cell Biol ; 102(2): 169-178, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37917979

RESUMEN

Esophageal squamous cell carcinoma (ESCC) is a common malignancy with high morbidity and mortality. Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) serves as a reader of RNA m6A (N6 methyladenosine) modification to regulate gene expression at the post-transcriptional level. Emerging evidence suggests that IGF2BP2 plays critical roles in tumorigenesis and malignant development. However, the biological function and molecular mechanism of IGF2BP2 in ESCC are not well understood. Here, we found that IGF2BP2 expression was upregulated in esophageal cancer tissues and ESCC cells, and IGF2BP2 overexpression enhanced proliferation, migration, invasion, and stem cell-like properties of ESCC cells. Conversely, the knockdown of IGF2BP2 expression inhibited malignant phenotype of ESCC cells. Mechanistically, IGF2BP2 upregulated octomer-binding transcription factor 4 (OCT4) mRNA expression, and RNA immunoprecipitation (RIP) assay proved that IGF2BP2 could interact with OCT4 mRNA. Moreover, OCT4 was modified at m6A confirmed by methylated m6A RNA immunoprecipitation (Me-RIP)-qPCR assay, and IGF2BP2 knockdown reduced OCT4 mRNA stability. These results suggested that IGF2BP2 served as a reader for m6A-modified OCT4, thus increased OCT4 mRNA expression by regulating its stability. Furthermore, the knockdown of OCT4 could reverse the effects of IGF2BP2 on ESCC cells. In conclusion, these data indicate that IGF2BP2, as a reader for m6A, plays an oncogenic role by regulating OCT4 expression in ESCC, which provides new insights into targeting IGF2BP2/OCT4 axis for the therapy of ESCC.


Asunto(s)
Adenina/análogos & derivados , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , ARN Mensajero/genética , Carcinoma de Células Escamosas de Esófago/genética , Neoplasias Esofágicas/genética , ARN , Proliferación Celular , Línea Celular Tumoral , Proteínas de Unión al ARN/genética
8.
Br J Haematol ; 204(4): 1307-1324, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38462771

RESUMEN

Multiple myeloma (MM) is the second most common malignant haematological disease with a poor prognosis. The limit therapeutic progress has been made in MM patients with cancer relapse, necessitating deeper research into the molecular mechanisms underlying its occurrence and development. A genome-wide CRISPR-Cas9 loss-of-function screening was utilized to identify potential therapeutic targets in our research. We revealed that COQ2 plays a crucial role in regulating MM cell proliferation and lipid peroxidation (LPO). Knockout of COQ2 inhibited cell proliferation, induced cell cycle arrest and reduced tumour growth in vivo. Mechanistically, COQ2 promoted the activation of the MEK/ERK cascade, which in turn stabilized and activated MYC protein. Moreover, we found that COQ2-deficient MM cells increased sensitivity to the LPO activator, RSL3. Using an inhibitor targeting COQ2 by 4-CBA enhanced the sensitivity to RSL3 in primary CD138+ myeloma cells and in a xenograft mouse model. Nevertheless, co-treatment of 4-CBA and RSL3 induced cell death in bortezomib-resistant MM cells. Together, our findings suggest that COQ2 promotes cell proliferation and tumour growth through the activation of the MEK/ERK/MYC axis and targeting COQ2 could enhance the sensitivity to ferroptosis in MM cells, which may be a promising therapeutic strategy for the treatment of MM patients.


Asunto(s)
Mieloma Múltiple , Animales , Humanos , Ratones , Línea Celular Tumoral , Proliferación Celular , Sistemas CRISPR-Cas , Modelos Animales de Enfermedad , Peroxidación de Lípido , Quinasas de Proteína Quinasa Activadas por Mitógenos/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico
9.
Mol Carcinog ; 63(5): 977-990, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38376344

RESUMEN

Nickel pollution is a recognized factor contributing to lung cancer. Understanding the molecular mechanisms of its carcinogenic effects is crucial for lung cancer prevention and treatment. Our previous research identified the downregulation of a long noncoding RNA, maternally expressed gene 3 (MEG3), as a key factor in transforming human bronchial epithelial cells (HBECs) into malignant cells following nickel exposure. In our study, we found that deletion of MEG3 also reduced the expression of RhoGDIß. Notably, artificially increasing RhoGDIß levels counteracted the malignant transformation caused by MEG3 deletion in HBECs. This indicates that the reduction in RhoGDIß contributes to the transformation of HBECs due to MEG3 deletion. Further exploration revealed that MEG3 downregulation led to enhanced c-Jun activity, which in turn promoted miR-200c transcription. High levels of miR-200c subsequently increased the translation of AUF1 protein, stabilizing SOX2 messenger RNA (mRNA). This stabilization affected the regulation of miR-137, SP-1 protein translation, and the suppression of RhoGDIß mRNA transcription and protein expression, leading to cell transformation. Our study underscores the co-regulation of RhoGDIß expression by long noncoding RNA MEG3, multiple microRNAs (miR-200c and miR-137), and RNA-regulated transcription factors (c-Jun, SOX2, and SP1). This intricate network of molecular events sheds light on the nature of lung tumorigenesis. These novel findings pave the way for developing targeted strategies for the prevention and treatment of human lung cancer based on the MEG3/RhoGDIß pathway.


Asunto(s)
Neoplasias Pulmonares , MicroARNs , ARN Largo no Codificante , Humanos , Proliferación Celular/genética , Transformación Celular Neoplásica/genética , Regulación hacia Abajo , Células Epiteliales/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , MicroARNs/genética , MicroARNs/metabolismo , Níquel , Inhibidor beta de Disociación del Nucleótido Guanina rho/antagonistas & inhibidores , Inhibidor beta de Disociación del Nucleótido Guanina rho/genética , Inhibidor beta de Disociación del Nucleótido Guanina rho/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , ARN Mensajero , Factores de Transcripción SOXB1/genética , Ribonucleoproteína Nuclear Heterogénea D0/genética , Ribonucleoproteína Nuclear Heterogénea D0/metabolismo
10.
Brief Bioinform ; 23(3)2022 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-35262669

RESUMEN

Drug resistance is a major threat to the global health and a significant concern throughout the clinical treatment of diseases and drug development. The mutation in proteins that is related to drug binding is a common cause for adaptive drug resistance. Therefore, quantitative estimations of how mutations would affect the interaction between a drug and the target protein would be of vital significance for the drug development and the clinical practice. Computational methods that rely on molecular dynamics simulations, Rosetta protocols, as well as machine learning methods have been proven to be capable of predicting ligand affinity changes upon protein mutation. However, the severely limited sample size and heavy noise induced overfitting and generalization issues have impeded wide adoption of machine learning for studying drug resistance. In this paper, we propose a robust machine learning method, termed SPLDExtraTrees, which can accurately predict ligand binding affinity changes upon protein mutation and identify resistance-causing mutations. Especially, the proposed method ranks training data following a specific scheme that starts with easy-to-learn samples and gradually incorporates harder and diverse samples into the training, and then iterates between sample weight recalculations and model updates. In addition, we calculate additional physics-based structural features to provide the machine learning model with the valuable domain knowledge on proteins for these data-limited predictive tasks. The experiments substantiate the capability of the proposed method for predicting kinase inhibitor resistance under three scenarios and achieve predictive accuracy comparable with that of molecular dynamics and Rosetta methods with much less computational costs.


Asunto(s)
Aprendizaje Automático , Proteínas , Ligandos , Simulación de Dinámica Molecular , Mutación , Proteínas/química
11.
J Transl Med ; 22(1): 133, 2024 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-38310229

RESUMEN

BACKGROUND: Oxaliplatin resistance usually leads to therapeutic failure and poor prognosis in colorectal cancer (CRC), while the underlying mechanisms are not yet fully understood. Metabolic reprogramming is strongly linked to drug resistance, however, the role and mechanism of metabolic reprogramming in oxaliplatin resistance remain unclear. Here, we aim to explore the functions and mechanisms of purine metabolism on the oxaliplatin-induced apoptosis of CRC. METHODS: An oxaliplatin-resistant CRC cell line was generated, and untargeted metabolomics analysis was conducted. The inosine 5'-monophosphate dehydrogenase type II (IMPDH2) expression in CRC cell lines was determined by quantitative real-time polymerase chain reaction (qPCR) and western blotting analysis. The effects of IMPDH2 overexpression, knockdown and pharmacological inhibition on oxaliplatin resistance in CRC were assessed by flow cytometry analysis of cell apoptosis in vivo and in vitro. RESULTS: Metabolic analysis revealed that the levels of purine metabolites, especially guanosine monophosphate (GMP), were markedly elevated in oxaliplatin-resistant CRC cells. The accumulation of purine metabolites mainly arose from the upregulation of IMPDH2 expression. Gene set enrichment analysis (GSEA) indicated high IMPDH2 expression in CRC correlates with PURINE_METABOLISM and MULTIPLE-DRUG-RESISTANCE pathways. CRC cells with higher IMPDH2 expression were more resistant to oxaliplatin-induced apoptosis. Overexpression of IMPDH2 in CRC cells resulted in reduced cell death upon treatment with oxaliplatin, whereas knockdown of IMPDH2 led to increased sensitivity to oxaliplatin through influencing the activation of the Caspase 7/8/9 and PARP1 proteins on cell apoptosis. Targeted inhibition of IMPDH2 by mycophenolic acid (MPA) or mycophenolate mofetil (MMF) enhanced cell apoptosis in vitro and decreased in vivo tumour burden when combined with oxaliplatin treatment. Mechanistically, the Wnt/ß-catenin signalling was hyperactivated in oxaliplatin-resistant CRC cells, and a reciprocal positive regulatory mechanism existed between Wnt/ß-catenin and IMPDH2. Blocking the Wnt/ß-catenin pathway could resensitize resistant cells to oxaliplatin, which could be restored by the addition of GMP. CONCLUSIONS: IMPDH2 is a predictive biomarker and therapeutic target for oxaliplatin resistance in CRC.


Asunto(s)
Neoplasias Colorrectales , beta Catenina , Humanos , Apoptosis , beta Catenina/metabolismo , Línea Celular Tumoral , Proliferación Celular , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica , IMP Deshidrogenasa/genética , IMP Deshidrogenasa/metabolismo , Oxaliplatino/farmacología , Oxaliplatino/uso terapéutico , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Vía de Señalización Wnt
12.
New Phytol ; 242(6): 2524-2540, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38641854

RESUMEN

Leaf senescence is a complex process strictly regulated by various external and endogenous factors. However, the key signaling pathway mediating leaf senescence remains unknown. Here, we show that Arabidopsis SPX1/2 negatively regulate leaf senescence genetically downstream of the strigolactone (SL) pathway. We demonstrate that the SL receptor AtD14 and MAX2 mediate the age-dependent degradation of SPX1/2. Intriguingly, we uncover an age-dependent accumulation of SLs in leaves via transcriptional activation of SL biosynthetic genes by the transcription factors (TFs) SPL9/15. Furthermore, we reveal that SPX1/2 interact with the WRKY75 subclade TFs to inhibit their DNA-binding ability and thus repress transcriptional activation of salicylic acid (SA) biosynthetic gene SA Induction-Deficient 2, gating the age-dependent SA accumulation in leaves at the leaf senescence onset stage. Collectively, our new findings reveal a signaling pathway mediating sequential activation of SL and salicylate biosynthesis for the onset of leaf senescence in Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Regulación de la Expresión Génica de las Plantas , Lactonas , Hojas de la Planta , Senescencia de la Planta , Factores de Transcripción , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/efectos de los fármacos , Hojas de la Planta/metabolismo , Hojas de la Planta/efectos de los fármacos , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Lactonas/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Ácido Salicílico/metabolismo , Salicilatos/metabolismo , Transducción de Señal , Unión Proteica/efectos de los fármacos , Proteolisis/efectos de los fármacos , Vías Biosintéticas/efectos de los fármacos , Vías Biosintéticas/genética
13.
Plant Physiol ; 193(2): 1580-1596, 2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37335918

RESUMEN

Brassinosteroids play an essential role in promoting skotomorphogenesis, yet the underlying mechanisms remain unknown. Here we report that a plant-specific BLISTER (BLI) protein functions as a positive regulator of both BR signaling and skotomorphogenesis in Arabidopsis (Arabidopsis thaliana). We found that the glycogen synthase kinase 3 (GSK3)-like kinase BRASSINOSTEROID INSENSITIVE2 interacts with and phosphorylates BLI at 4 phosphorylation sites (Ser70, Ser146, Thr256, and Ser267) for degradation; in turn, BR inhibits degradation of BLI. Specifically, BLI cooperates with the BRASSINAZOLE RESISTANT1 (BZR1) transcription factor to facilitate the transcriptional activation of BR-responsive genes. Genetic analyses indicated that BLI is essentially required for BZR1-mediated hypocotyl elongation in the dark. Intriguingly, we reveal that BLI and BZR1 orchestrate the transcriptional expression of gibberellin (GA) biosynthetic genes to promote the production of bioactive GAs. Our results demonstrate that BLI acts as an essential regulator of Arabidopsis skotomorphogenesis by promoting BR signaling and GA biosynthesis.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Fosforilación , Glucógeno Sintasa Quinasa 3/genética , Brasinoesteroides/metabolismo , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo
14.
Toxicol Appl Pharmacol ; 487: 116960, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38735592

RESUMEN

BACKGROUND: The intestinal metabolites are involved in the initiation, progression and metastasis of colorectal cancer (CRC). They are a potential source of agents for cancer therapy. Our previous study identified altered faecal metabolites between CRC patients and healthy volunteers. However, no specific metabolite was clearly illustrated for CRC therapy. RESULTS: We found that the level of xylulose was lower in the stools of CRC patients than in those of healthy volunteers. Xylulose inhibited cell growth without affecting the cell cycle by inducing apoptosis in CRC cells, which was evidenced by increased expression of the proapoptotic proteins C-PARP and C-Caspase3 and decreased expression of the antiapoptotic protein BCL-2 in CRC cells. Mechanistically, xylulose reduced the activity of the MAPK signalling pathway, represented by reduced phosphorylation of JNK, ERK, and P38. Furthermore, an ALI model was used to show the tumour killing ability of xylulose on human CRC spheres, as well as human colorectal adenoma (AD) spheres. CONCLUSION: Xylulose inhibits CRC growth by inducing apoptosis through attenuation of the MAPK signalling pathway. These results suggest that xylulose may serve as an effective agent for CRC therapy.


Asunto(s)
Apoptosis , Neoplasias Colorrectales , Sistema de Señalización de MAP Quinasas , Xilulosa , Humanos , Apoptosis/efectos de los fármacos , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Xilulosa/farmacología , Xilulosa/metabolismo , Masculino , Animales , Femenino , Proliferación Celular/efectos de los fármacos , Heces/química , Persona de Mediana Edad , Línea Celular Tumoral , Antineoplásicos/farmacología , Células HT29 , Anciano
15.
Reprod Biol Endocrinol ; 22(1): 24, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38373962

RESUMEN

BACKGROUND: Polycystic ovary syndrome (PCOS) is one of the most common reproductive endocrine disorders in females of childbearing age. Various types of ovarian cells work together to maintain normal reproductive function, whose discordance often takes part in the development and progression of PCOS. Understanding the cellular heterogeneity and compositions of ovarian cells would provide insight into PCOS pathogenesis, but are, however, not well understood. Transcriptomic characterization of cells isolated from PCOS cases have been assessed using bulk RNA-seq but cells isolated contain a mixture of many ovarian cell types. METHODS: Here we utilized the reference scRNA-seq data from human adult ovaries to deconvolute and estimate cell proportions and dysfunction of ovarian cells in PCOS, by integrating various granulosa cells(GCs) transcriptomic data. RESULTS: We successfully defined 22 distinct cell clusters of human ovarian cells. Then after transcriptome integration, we obtained a gene expression matrix with 13,904 genes within 30 samples (15 control vs. 15 PCOS). Subsequent deconvolution analysis revealed decreased proportion of small antral GCs and increased proportion of KRT8high mural GCs, HTRA1high cumulus cells in PCOS, especially increased differentiation from small antral GCs to KRT8high mural GCs. For theca cells, the abundance of internal theca cells (TCs) and external TCs was both increased. Less TCF21high stroma cells (SCs) and more STARhigh SCs were observed. The proportions of NK cells and monocytes were decreased, and T cells occupied more in PCOS and communicated stronger with inTCs and exTCs. In the end, we predicted the candidate drugs which could be used to correct the proportion of ovarian cells in patients with PCOS. CONCLUSIONS: Taken together, this study provides insights into the molecular alterations and cellular compositions in PCOS ovarian tissue. The findings might contribute to our understanding of PCOS pathophysiology and offer resource for PCOS basic research.


Asunto(s)
Síndrome del Ovario Poliquístico , Adulto , Femenino , Humanos , Síndrome del Ovario Poliquístico/metabolismo , Transcriptoma , Células de la Granulosa/metabolismo , Perfilación de la Expresión Génica , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética
16.
BMC Cancer ; 24(1): 737, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38879516

RESUMEN

BACKGROUND: Bladder cancer (BC) is among the most prevalent malignant urothelial tumors globally, yet the prognosis for patients with muscle-invasive bladder cancer (MIBC) remains dismal, with a very poor 5-year survival rate. Consequently, identifying more effective and less toxic chemotherapeutic alternatives is critical for enhancing clinical outcomes for BC patients. Isorhapontigenin (ISO), a novel stilbene isolated from a Gnetum found in certain provinces of China, has shown potential as an anticancer agent due to its diverse anticancer activities. Despite its promising profile, the specific anticancer effects of ISO on BC and the underlying mechanisms are still largely unexplored. METHODS: The anchorage-independent growth, migration and invasion of BC cells were assessed by soft agar and transwell invasion assays, respectively. The RNA levels of SOX2, miR-129 and SNHG1 were quantified by qRT-PCR, while the protein expression levels were validated through Western blotting. Furthermore, methylation-specific PCR was employed to assess the methylation status of the miR-129 promoter. Functional assays utilized siRNA knockdown, plasmid-mediated overexpression, and chemical inhibition approaches. RESULTS: Our study demonstrated that ISO treatment significantly reduced SNHG1 expression in a dose- and time-dependent manner in BC cells, leading to the inhibition of anchorage-independent growth and invasion in human basal MIBC cells. This effect was accompanied by the downregulation of MMP-2 and MMP-9 and the upregulation of the tumor suppressor PTEN. Further mechanistic investigations revealed that SOX2, a key upstream regulator of SNHG1, played a crucial role in mediating the ISO-induced transcriptional suppression of SNHG1. Additionally, we found that ISO treatment led to a decrease in DNMT3b protein levels, which in turn mediated the hypomethylation of the miR-129 promoter and the subsequent suppression of SOX2 mRNA 3'-UTR activity, highlighting a novel pathway through which ISO exerts its anticancer effects. CONCLUSIONS: Collectively, our study highlights the critical role of SNHG1 downregulation as well as its upstream DNMT3b/miR-129/SOX2 axis in mediating ISO anticancer activity. These findings not only elucidate the mechanism of action of ISO but also suggest novel targets for BC therapy.


Asunto(s)
ADN (Citosina-5-)-Metiltransferasas , ADN Metiltransferasa 3B , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , ARN Largo no Codificante , Estilbenos , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/metabolismo , ARN Largo no Codificante/genética , Línea Celular Tumoral , Estilbenos/farmacología , Estilbenos/uso terapéutico , Regulación hacia Abajo/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , ADN (Citosina-5-)-Metiltransferasas/genética , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Invasividad Neoplásica , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Metilación de ADN/efectos de los fármacos , MicroARNs/genética
17.
Bioorg Chem ; 146: 107308, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38531151

RESUMEN

Genome mining of the Actinomycete Crossiella cryophila facilitated the discovery of a minimal terpenoid biosynthetic gene cluster of cry consisting of a class I terpene cyclase CryA and a CYP450 monooxygenase CryB. Heterologous expression of cry allowed the isolation and characterization of two new sesquiterpenoids, ent-viridiflorol (1) and cryophilain (2). Notably, cryophilain (2) possesses a 5/7/3-fused tricyclic skeleton bearing a distinctive bridgehead hydroxy group. The combined in vivo and in vitro experiments revealed that CryA, the first ent-viridiflorol terpene cyclase, catalyzes farnesyl diphosphate to form the 5/7/3 sesquiterpene core scaffold and P450 CryB serves as a tailoring enzyme responsible for installing a hydroxy group at the bridgehead carbon.


Asunto(s)
Actinobacteria , Actinomycetales , Sesquiterpenos , Terpenos , Sesquiterpenos/metabolismo , Actinobacteria/genética , Actinobacteria/metabolismo , Actinomycetales/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo
18.
J Nanobiotechnology ; 22(1): 154, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38581017

RESUMEN

The combination of immune checkpoint inhibitors and immunogenic cell death (ICD) inducers has become a promising strategy for the treatment of various cancers. However, its efficacy remains unmet because of the dense stroma and defective vasculatures in the tumor microenvironment (TME) that restricts the intratumoral infiltration of cytotoxic T lymphocytes (CTLs). Herein, cancer-associated fibroblasts (CAFs)-targeted nanoemulsions are tailored to combine the ICD induction and the TME reprogramming to sensitize checkpoint blockade immunotherapy. Melittin, as an ICD inducer and an antifibrotic agent, is efficiently encapsulated into the nanoemulsion accompanied by a nitric oxide donor to improve its bioavailability and tumor targeting. The nanoemulsions exhibited dual functionality by directly inducing direct cancer cell death and enhancing the tumoral immunogenicity, while also synergistically reprogramming the TME through reversing the activated CAFs, decreasing collagen deposition and restoring tumor vessels. Consequently, these nanemulsions successfully facilitated the CTLs infiltration and suppressing the recruitment of immunosuppressive cells. A combination of AE-MGNPs and anti-CTLA-4 antibody greatly elicited a striking level of antitumor T-cell response to suppress tumor growth in CAFs-rich colorectal tumor models. Our work emphasized the integration of the ICD induction with simultaneous modulation of the TME to enhance the sensitivity of patients to checkpoint blockade immunotherapy.


Asunto(s)
Antineoplásicos , Neoplasias Colorrectales , Neoplasias , Humanos , Microambiente Tumoral , Inhibidores de Puntos de Control Inmunológico/farmacología , Antineoplásicos/farmacología , Neoplasias/tratamiento farmacológico , Inmunoterapia , Línea Celular Tumoral
19.
Drug Resist Updat ; 71: 101002, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37678078

RESUMEN

Adenocarcinoma is a common type of malignant tumor, originating from glandular epithelial cells in various organs, such as pancreas, breast, lung, stomach, colon, rectus, and prostate. For patients who lose the opportunity for radical surgery, medication is available to provide potential clinical benefits. However, drug resistance is a big obstacle to obtain desired clinical prognosis. In this review, we provide a summary of treatment strategies and drug resistance mechanisms in adenocarcinoma of different organs, including pancreatic cancer, gastric adenocarcinoma, colorectal adenocarcinoma, lung adenocarcinoma, and prostate cancer. Although the underlying molecular mechanisms involved in drug resistance of adenocarcinoma vary from one organ to the other, there are several targets that are universal for drug resistance in adenocarcinoma, and targeting these molecules could potentially reverse drug resistance in the treatment of adenocarcinomas.


Asunto(s)
Adenocarcinoma , Neoplasias Colorrectales , Neoplasias Pancreáticas , Neoplasias de la Próstata , Masculino , Humanos , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/genética
20.
Am J Perinatol ; 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38531377

RESUMEN

OBJECTIVE: Our objective was to evaluate the quality of obstetrical ultrasound images obtained with coconut oil compared with commercial ultrasound gel and to assess patient acceptability. STUDY DESIGN: This was a randomized two-period crossover study in which 40 pregnant patients had standard biometry images obtained with both coconut oil and commercial ultrasound gel during their growth or anatomy ultrasound. All images were then rated by two blinded maternal-fetal medicine physicians on quality, resolution, and detail using a 0 to 100 scale. Contrasts obtained from linear mixed models were used to estimate the differences in image parameters between the agents. Participant experience was evaluated with an acceptability survey which included five items measured on a five-point Likert scale. RESULTS: Image quality, as rated by physicians, was found to be equivalent between commercial ultrasound gel and coconut oil. Additionally, there was not a statistically significant difference in image resolution or detail between the two coupling agents. The overall patient experience was significantly lower for commercial ultrasound gel when compared with coconut oil (mean difference = - 5.48, 95% confidence interval = [-6.89, -4.06]). CONCLUSION: Ultrasound images collected with coconut oil as the coupling agent are equivalent in quality to those collected using commercial ultrasound gel. Patients also preferred the use of coconut oil during their ultrasound, making its use a possible way to improve the patient ultrasound experience. Coconut oil has the potential as an alternative coupling agent that could significantly increase access to ultrasound use in resource-limited settings. KEY POINTS: · Coconut oil produces quality images during obstetrical ultrasounds.. · Patients prefer the use of coconut oil to standard ultrasound gel during obstetrical ultrasounds.. · Coconut oil is a coupling agent that could increase ultrasound use in resource-limited settings..

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