Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 90
Filtrar
1.
Cell Biochem Biophys ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39283585

RESUMEN

Recently, numerous studies have revealed the participation of circular RNAs (circRNAs) in cancer progression. Likewise, this research focused on circRNAs in hepatocellular carcinoma (HCC). A lowly expressed circRNA hsa_circ_0072309 in HCC was screened by analyzing the circRNA microarray GSE242797 and GSE216115 and identified in clinical specimens and cells. Subsequently, CCK-8, colony formation, and transwell assays were performed. The results revealed that hsa_circ_0072309 overexpression suppressed HCC cell proliferation, migration, invasion, and sorafenib resistance, whereas its suppression showed opposite results. Mechanistic investigation found an interaction between hsa_circ_0072309 and its host gene leukemia inhibitory factor receptor (LIFR) in HCC. We found that LIFR overexpression promoted the hsa_circ_0072309 formation. In turn, hsa_circ_0072309 recruited the E1A binding protein p300 to promote the enrichment of H3K27 acetylation (H3K27ac) in the LIFR enhancer, thus transcriptionally promoting LIFR expression. To conclude, we revealed a hsa_circ_0072309/LIFR regulatory loop in HCC, which may provide a potential target for HCC treatment.

2.
Curr Med Chem ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39252620

RESUMEN

Lung cancer is the second malignant tumor in the world and is the most prevalent malignant tumor of the respiratory system. In lung cancer, the P2X7 receptor (P2X7R) is an important purinergic receptor. P2X7R is a class of ionotropic adenosine triphosphate (ATP)-gated receptors, which exists in many kinds of immune tissues and cells and is involved in tumorigenesis and progression. P2X7R is closely related to lung cancer and is expressed at higher levels in lung cancer than in normal lung tissue. P2X7R plays a critical regulatory function in lung cancer invasion and migration through multiple mechanisms of action and affects the proliferation and apoptosis of cancer cells in the lung. Antagonists of P2X7R can block its function, which in turn has a significant inhibitory effect on lung cancer cell development and progression. This paper details a comprehensive overview of the structure and function of P2X7R. It focuses on the impact and treatment potential of P2X7R in lung cancer invasion, migration, proliferation, and apoptosis, providing new ideas and a new basis for clinical lung cancer treatment and prognosis.

3.
J Mol Histol ; 55(5): 927-936, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39160363

RESUMEN

Hepatocellular carcinoma (HCC) has a high mortality rate, and the identification of early prognostic markers is crucial for improving patient outcomes. This study aimed to investigate the correlation between the expression of Histocompatibility Minor 13 (HM13) and the prognosis of HCC patients. HM13 protein expression was assessed in HCC tissues and cells through immunohistochemistry (IHC), quantitative reverse transcription PCR (qRT-PCR), and western blot. The relationship between HM13 expression and clinicopathological data of HCC was evaluated. Bioinformatics analyses, including Gene Expression Omnibus (GEO) database, Gene Expression Profiling Interactive Analysis (GEPIA), and Kaplan-Meier plotter (K-M plotter), were employed to analyze HM13 expression and its association with patient survival. HM13 was significantly overexpressed in HCC tissues and cells compared to normal controls. IHC revealed that HM13 protein was primarily localized in the cytoplasm and highly expressed in HCC tissues. Interestingly, patients with high HM13 expression had significantly poorer overall survival (OS), progression-free survival (PFS), recurrence-free survival (RFS), and disease-specific survival (DSS) than those with low expression. HM13 expression was associated with Edmondson grade, metastasis, microvascular invasion, and alpha-fetoprotein (AFP) levels. Multivariate analysis identified HM13 as an independent prognostic factor for poor OS in HCC. HM13 was markedly overexpressed in HCC and correlated with poor prognosis, suggesting its potential as a promising biomarker for early prognostic detection in HCC patients.


Asunto(s)
Biomarcadores de Tumor , Carcinoma Hepatocelular , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/diagnóstico , Femenino , Masculino , Pronóstico , Persona de Mediana Edad , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Estimación de Kaplan-Meier , Inmunohistoquímica
4.
Purinergic Signal ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39039304

RESUMEN

Breast cancer is a common malignant tumor, whose incidence is increasing year by year, and it has become the malignant tumor with the highest incidence rate in women. Purine ligand-gated ion channel 7 receptor (P2X7R) is a cation channel receptor with Adenosine triphosphate ( ATP) as a ligand, which is widely distributed in cells and tissues, and is closely related to tumorigenesis and progression. P2X7R plays an important role in cancer by interacting with ATP. Studies have shown that P2X7R is up-regulated in breast cancer and can promote tumor invasion and metastasis by activating the protein kinase B (AKT) signaling pathway, promoting epithelial-mesenchymal transition (EMT), controlling the generation of extracellular vesicle (EV), and regulating the expression of the inflammatory protein cyclooxygenase 2 (COX-2). Furthermore, P2X7R was proven to play an essential role in the proliferation and apoptosis of breast cancer cells. Recently, inhibitors targeting P2X7R have been found to inhibit the progression of breast cancer. Natural P2X7R antagonists, such as rhodopsin, and the isoquinoline alkaloid berberine, have also been shown to be effective in inhibiting breast cancer progression. In this article, we review the research progress of P2X7R and breast cancer intending to provide new targets and directions for breast cancer treatment.

5.
Artículo en Inglés | MEDLINE | ID: mdl-39073415

RESUMEN

In the course of clinical treatment for anti-tumor, the combination of traditional Chinese medicine (TCM) and other treatment schemes can reduce toxicity and increase efficiency. The purpose of this paper is to find out the key TCM and effective components for the treatment of non-small cell lung cancer (NSCLC) and analyze its therapeutic mechanism by analyzing the prescription of TCM combined with chemotherapy for NSCLC. Firstly, the prescriptions of TCM in the randomized controlled trials combined with chemotherapy for NSCLC were collected, and the core TCM was screened by frequency statistics, association rule analysis, and cluster analysis. Then, the intersection targets of the potential effects of NSCLC and core Chinese medicine were collected, and PPI analysis and enrichment analysis were performed on the intersection targets to screen the core targets, components, and pathways. The core components were verified by molecular docking and cell experiments. In this study, 269 prescriptions were collected, among which the frequency of medication for Astragalus membranaceus (HQ, in Chinese), Wolfiporia cocos (FL, in Chinese), and Atractylodes macrocephala (BZ, in Chinese) was over 100. Association rule analysis showed that they were highly correlated and clustered into the same category in cluster analysis. Their core components were quercetin, kaempferol, and isorhamnetin. The molecular docking results of the core components with the core targets AKT1 and EGFR obtained by PPI network analysis showed that they could bind stably. KEGG analysis screened 110 pathways including PI3K-Akt; the results of CCK-8 showed that quercetin, kaempferol, and isorhamnetin could effectively inhibit the proliferation of A549 cells, and isorhamnetin had the best inhibitory effect. Isorhamnetin can inhibit the migration and invasion of A549 cells, induce apoptosis and G1 phase arrest, and decrease the expression of P-PI3K and P-AKT in A549 cells. In a word, the key TCM for the treatment of NSCLC includes HQ, FL, and BZ. and its key components quercetin, kaempferol, and isorhamnetin have potential therapeutic effects on NSCLC according to the research results.

6.
J Med Chem ; 67(15): 12835-12854, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39026395

RESUMEN

Substituting hydrogen with deuterium in drug molecules is an appealing bioisosteric strategy for the generation of novel chemical entities in drug development. Optimizing lead compounds through deuteration has proven to be challenging and unpredictable, particularly for compounds with multiple metabolic sites. This study presents the pioneering achievement of substituting up to 19 hydrogen atoms with deuterium on 1,4-benzodiazepine-2,5-dione derivatives, shedding light on the structure-metabolism relationship and the impact of multiple deuterations on drug-like properties. Notably, the deuterated compound 3f exhibited remarkable antitumor activity in vivo and demonstrated favorable drug-like properties as a drug candidate.


Asunto(s)
Antineoplásicos , Deuterio , Deuterio/química , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Animales , Humanos , Relación Estructura-Actividad , Línea Celular Tumoral , Ratones , Benzodiazepinas/química , Benzodiazepinas/farmacología , Benzodiazepinas/síntesis química
7.
Adv Healthc Mater ; : e2400780, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850154

RESUMEN

Cell encapsulation technology, crucial for advanced biomedical applications, faces challenges in existing microfluidic and electrospray methods. Microfluidic techniques, while precise, can damage vulnerable cells, and conventional electrospray methods often encounter instability and capsule breakage during high-throughput encapsulation. Inspired by the transformation of the working state from unstable dripping to stable jetting triggered by local electric potential, this study introduces a superimposed electric field (SEF)-enhanced electrospray method for cell encapsulation, with improved stability and biocompatibility. Utilizing stiffness theory, the stability of the electrospray, whose stiffness is five times stronger under conical confinement, is quantitatively analyzed. The SEF technique enables rapid, continuous production of ≈300 core-shell capsules per second in an aqueous environment, significantly improving cell encapsulation efficiency. This method demonstrates remarkable potential as exemplified in two key applications: (1) a 92-fold increase in human-derived induced pluripotent stem cells (iPSCs) expansion over 10 d, outperforming traditional 2D cultures in both growth rate and pluripotency maintenance, and (2) the development of liver capsules for steatosis modeling, exhibiting normal function and biomimetic lipid accumulation. The SEF-enhanced electrospray method presents a significant advancement in cell encapsulation technology. It offers a more efficient, stable, and biocompatible approach for clinical transplantation, drug screening, and cell therapy.

8.
Front Psychiatry ; 15: 1392958, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38751414

RESUMEN

Background: Pediatric cerebral palsy (CP) is a non-progressive brain injury syndrome characterized by central motor dysfunction and insufficient brain coordination ability. The etiology of CP is complex and often accompanied by diverse complications such as intellectual disability and language disorders, making clinical treatment difficult. Despite the availability of pharmacological interventions, rehabilitation programs, and spasticity relief surgery as treatment options for CP, their effectiveness is still constrained. Electroacupuncture (EA) stimulation has demonstrated great improvements in motor function, but its comprehensive, objective therapeutic effects on pediatric CP remain to be clarified. Methods: We present a case of a 5-year-old Chinese female child who was diagnosed with CP at the age of 4. The patient exhibited severe impairments in motor, language, social, and cognitive functions. We performed a 3-month period of EA rehabilitation, obtaining resting state functional magnetic resonance imaging (rs-fMRI) of the patient at 0 month, 3 months and 5 months since treatment started, then characterized brain functional connectivity patterns in each phase for comparison. Results: After a 12-month follow-up, notable advancements were observed in the patient's language and social symptoms. Changes of functional connectivity patterns confirmed this therapeutic effect and showed specific benefits for different recovery phase: starting from language functions then modulating social participation and other developmental behaviors. Conclusion: This is a pioneering report demonstrating the longitudinal effect of EA stimulation on functional brain connectivity in CP patients, suggesting EA an effective intervention for developmental disabilities (especially language and social dysfunctions) associated with pediatric CP.

9.
J Cancer Res Ther ; 20(2): 625-632, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38687933

RESUMEN

OBJECTIVE: To establish a multimodal model for distinguishing benign and malignant breast lesions. MATERIALS AND METHODS: Clinical data, mammography, and MRI images (including T2WI, diffusion-weighted images (DWI), apparent diffusion coefficient (ADC), and DCE-MRI images) of 132 benign and breast cancer patients were analyzed retrospectively. The region of interest (ROI) in each image was marked and segmented using MATLAB software. The mammography, T2WI, DWI, ADC, and DCE-MRI models based on the ResNet34 network were trained. Using an integrated learning method, the five models were used as a basic model, and voting methods were used to construct a multimodal model. The dataset was divided into a training set and a prediction set. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of the model were calculated. The diagnostic efficacy of each model was analyzed using a receiver operating characteristic curve (ROC) and an area under the curve (AUC). The diagnostic value was determined by the DeLong test with statistically significant differences set at P < 0.05. RESULTS: We evaluated the ability of the model to classify benign and malignant tumors using the test set. The AUC values of the multimodal model, mammography model, T2WI model, DWI model, ADC model and DCE-MRI model were 0.943, 0.645, 0.595, 0.905, 0.900, and 0.865, respectively. The diagnostic ability of the multimodal model was significantly higher compared with that of the mammography and T2WI models. However, compared with the DWI, ADC, and DCE-MRI models, there was no significant difference in the diagnostic ability of these models. CONCLUSION: Our deep learning model based on multimodal image training has practical value for the diagnosis of benign and malignant breast lesions.


Asunto(s)
Neoplasias de la Mama , Aprendizaje Profundo , Mamografía , Imagen Multimodal , Humanos , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Femenino , Diagnóstico Diferencial , Persona de Mediana Edad , Mamografía/métodos , Adulto , Estudios Retrospectivos , Imagen Multimodal/métodos , Anciano , Imagen por Resonancia Magnética/métodos , Curva ROC , Interpretación de Imagen Asistida por Computador/métodos , Imagen de Difusión por Resonancia Magnética/métodos , Mama/diagnóstico por imagen , Mama/patología
10.
Adv Sci (Weinh) ; 11(23): e2401611, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38509850

RESUMEN

Cell mechanotransduction signals are important targets for physical therapy. However, current physiotherapy heavily relies on ultrasound, which is generated by high-power equipment or amplified by auxiliary drugs, potentially causing undesired side effects. To address current limitations, a robotic actuation-mediated therapy is developed that utilizes gentle mechanical loads to activate mechanosensitive ion channels. The resulting calcium influx precisely regulated the expression of recombinant tumor suppressor protein and death-associated protein kinase, leading to programmed apoptosis of cancer cell line through caspase-dependent pathway. In stark contrast to traditional gene therapy, the complete elimination of early- and middle-stage tumors (volume ≤ 100 mm3) and significant growth inhibition of late-stage tumor (500 mm3) are realized in tumor-bearing mice by transfecting mechanogenetic circuits and treating daily with quantitative robotic actuation in a form of 5 min treatment over the course of 14 days. Thus, this massage-derived therapy represents a quantitative strategy for cancer treatment.


Asunto(s)
Mecanotransducción Celular , Neoplasias , Robótica , Animales , Ratones , Mecanotransducción Celular/genética , Robótica/métodos , Neoplasias/terapia , Neoplasias/genética , Neoplasias/metabolismo , Línea Celular Tumoral , Humanos , Modelos Animales de Enfermedad , Apoptosis/genética
11.
Front Oncol ; 13: 1243126, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38044991

RESUMEN

Purpose: To evaluate the diagnostic performance of a deep learning model based on multi-modal images in identifying molecular subtype of breast cancer. Materials and methods: A total of 158 breast cancer patients (170 lesions, median age, 50.8 ± 11.0 years), including 78 Luminal A subtype and 92 non-Luminal A subtype lesions, were retrospectively analyzed and divided into a training set (n = 100), test set (n = 45), and validation set (n = 25). Mammography (MG) and magnetic resonance imaging (MRI) images were used. Five single-mode models, i.e., MG, T2-weighted imaging (T2WI), diffusion weighting imaging (DWI), axial apparent dispersion coefficient (ADC), and dynamic contrast-enhanced MRI (DCE-MRI), were selected. The deep learning network ResNet50 was used as the basic feature extraction and classification network to construct the molecular subtype identification model. The receiver operating characteristic curve were used to evaluate the prediction efficiency of each model. Results: The accuracy, sensitivity and specificity of a multi-modal tool for identifying Luminal A subtype were 0.711, 0.889, and 0.593, respectively, and the area under the curve (AUC) was 0.802 (95% CI, 0.657- 0.906); the accuracy, sensitivity, and AUC were higher than those of any single-modal model, but the specificity was slightly lower than that of DCE-MRI model. The AUC value of MG, T2WI, DWI, ADC, and DCE-MRI model was 0.593 (95%CI, 0.436-0.737), 0.700 (95%CI, 0.545-0.827), 0.564 (95%CI, 0.408-0.711), 0.679 (95%CI, 0.523-0.810), and 0.553 (95%CI, 0.398-0.702), respectively. Conclusion: The combination of deep learning and multi-modal imaging is of great significance for diagnosing breast cancer subtypes and selecting personalized treatment plans for doctors.

12.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 35(10): 1070-1073, 2023 Oct.
Artículo en Chino | MEDLINE | ID: mdl-37873712

RESUMEN

OBJECTIVE: To explore the feasibility of snuff pot arterial pressure measurement for patients undergoing routine elective surgery during anesthesia. METHODS: A prospective randomized controlled trial was conducted. Patients undergoing elective surgery admitted to the Handan Hospital of Traditional Chinese Medicine from June 1, 2020 to June 1, 2022 were enrolled. Patients who needed arterial pressure measurement for hemodynamic monitoring were randomly divided into routine radial artery puncture group and snuff pot artery puncture group with their informed consent. The patients in the routine radial artery puncture group were placed a catheter at the styloid process of the patient's radius to measure pressure. In the snuff pot artery puncture group, the snuff pot artery, that was, the radial fossa on the back of the hand (snuff box), was selected to conduct the snuff pot artery puncture and tube placement for pressure measurement. The indwelling time of arterial puncture catheter, arterial blood pressure, and complications of puncture catheterization of patients in the two groups were observed. Multivariate Logistic regression analysis was used to screen the relevant factors that affect the outcome of arterial catheterization. RESULTS: Finally, a total of 252 patients were enrolled, of which 130 patients received routine radial artery puncture and 122 patients received snuff pot artery puncture. There was no statistically significant difference in general information such as gender, age, body mass index (BMI), and surgical type of patients between the two groups. There was no significant difference in the indwelling time of artery puncture catheter between the routine radial artery puncture group and the snuff pot artery puncture group (minutes: 3.4±0.3 vs. 3.6±0.3, P > 0.05). The systolic blood pressure (SBP) and the diastolic blood pressure (DBP) measured in the snuff pot artery puncture group were significantly higher than those in the conventional radial artery puncture group [SBP (mmHg, 1 mmHg ≈ 0.133 kPa): 162.3±14.3 vs. 156.6±12.5, DBP (mmHg): 85.3±12.6 vs. 82.9±11.3, both P < 0.05]. There was no statistically significant difference in the incidence of complications such as arterial spasm, arterial occlusion, and pseudoaneurysm formation between the two groups. However, the incidence of hematoma formation in the snuff pot artery puncture group was significantly lower than that in the conventional radial artery puncture group (2.5% vs. 4.6%, P < 0.05). Based on the difficulty of arterial puncture, multivariate Logistic regression analysis showed that gender [odds ratio (OR) = 0.643, 95% confidence interval (95%CI) was 0.525-0.967], age (OR = 2.481, 95%CI was 1.442-4.268) and BMI (OR = 0.786, 95%CI was 0.570-0.825) were related factors that affect the outcome of arterial catheterization during anesthesia in patients undergoing elective surgery (all P < 0.05). CONCLUSIONS: Catheterization through the snuff pot artery can be a new and feasible alternative to conventional arterial pressure measurement.


Asunto(s)
Cateterismo Periférico , Tabaco sin Humo , Humanos , Presión Arterial/fisiología , Estudios de Factibilidad , Arteria Radial/fisiología , Estudios Prospectivos , Punciones
13.
Biomaterials ; 302: 122323, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37717405

RESUMEN

Cancer stem cells (CSCs) are crucial for tumorigenesis, metastasis, and therapy resistance in esophageal squamous cell carcinoma (ESCC). To further elucidate the mechanism underlying characteristics of CSCs and develop CSCs-targeted therapy, an efficient culture system that could expand and maintain CSCs is needed. CSCs reside in a complex tumor microenvironment, and three-dimensional (3D) culture systems of biomimetic scaffolds are expected to better support the growth of CSCs by recapitulating the biophysical properties of the extracellular matrix (ECM). Here, we established gelatin-based 3D biomimetic scaffolds mimicking the stiffness and collagen content of ESCC, which could enrich ESCC CSCs efficiently. Biological changes of ESCC cells laden in scaffolds with three different viscoelasticity emulating physiological stiffness of esophageal tissues were thoroughly investigated in varied aspects such as cell morphology, viability, cell phenotype markers, and transcriptomic profiling. The results demonstrated the priming effects of viscoelasticity on the stemness of ESCC. The highly viscous scaffolds (G': 6-403 Pa; G'': 2-75 Pa) better supported the enrichment of ESCC CSCs, and the TGF-beta signaling pathway might be involved in regulating the stemness of ESCC cells. Compared to two-dimensional (2D) cultures, highly viscous scaffolds significantly promoted the clonal expansion of ESCC cells in vitro and tumor formation ability in vivo. Our findings highlight the crucial role of biomaterials' viscoelasticity for the 3D culture of ESCC CSCs in vitro, and this newly-established culture system represents a valuable platform to support their growth, which could facilitate the CSCs-targeted therapy in the future.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/metabolismo , Carcinoma de Células Escamosas de Esófago/patología , Carcinoma de Células Escamosas de Esófago/terapia , Gelatina/farmacología , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Biomimética , Línea Celular Tumoral , Células Madre Neoplásicas/patología , Microambiente Tumoral
14.
Front Microbiol ; 14: 1231503, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37601380

RESUMEN

Pancreatic cancer is a devastating disease with a high mortality rate and a lack of effective therapies. The challenges associated with early detection and the highly aggressive nature of pancreatic cancer have limited treatment options, underscoring the urgent need for better disease-modifying therapies. Peptide-based biotherapeutics have become an attractive area of research due to their favorable properties such as high selectivity and affinity, chemical modifiability, good tissue permeability, and easy metabolism and excretion. Phage display, a powerful technique for identifying peptides with high affinity and specificity for their target molecules, has emerged as a key tool in the discovery of peptide-based drugs. Phage display technology involves the use of bacteriophages to express peptide libraries, which are then screened against a target of interest to identify peptides with desired properties. This approach has shown great promise in cancer diagnosis and treatment, with potential applications in targeting cancer cells and developing new therapies. In this comprehensive review, we provide an overview of the basic biology of phage vectors, the principles of phage library construction, and various methods for binding affinity assessment. We then describe the applications of phage display in pancreatic cancer therapy, targeted drug delivery, and early detection. Despite its promising potential, there are still challenges to be addressed, such as optimizing the selection process and improving the pharmacokinetic properties of phage-based drugs. Nevertheless, phage display represents a promising approach for the development of novel targeted therapies in pancreatic cancer and other tumors.

15.
Org Lett ; 25(30): 5650-5655, 2023 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-37490590

RESUMEN

Modification of organic molecules with fluorine functionalities offers a critical approach to develop new pharmaceuticals. Here, we report a multienzyme strategy for biocatalytic fluoroalkylation using S-adenosyl-l-methionine (SAM)-dependent methyltransferases (MTs) and fluorinated SAM cofactors prepared from ATP and fluorinated l-methionine analogues by an engineered human methionine adenosyltransferase hMAT2AI322A. This work introduces the first example of biocatalytic 3,3-difluoroallylation. Importantly, this strategy can be applied to late-stage site-selective fluoroalkylation of complex molecule vancomycin with conversions up to 99%.


Asunto(s)
Metionina , S-Adenosilmetionina , Humanos , Metionina/metabolismo , S-Adenosilmetionina/metabolismo , Metiltransferasas/metabolismo , Racemetionina , Biocatálisis
16.
J Vis Exp ; (197)2023 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-37486127

RESUMEN

Researchers in the cell and gene therapy (CGT) industry have long faced a formidable challenge in the efficient and large-scale expansion of cells. To address the primary shortcomings of the two-dimensional (2D) planar culturing system, we innovatively developed an automated closed industrial scale cell production (ACISCP) platform based on a GMP-grade, dissolvable, and porous microcarrier for the 3D culture of adherent cells, including human mesenchymal stem/stromal cells (hMSCs), HEK293T cells, and Vero cells. To achieve large-scale expansion, a two-stage expansion was conducted with 5 L and 15 L stirred-tank bioreactors to yield 1.1 x 1010 hMSCs with an overall 128-fold expansion within 9 days. The cells were harvested by completely dissolving the microcarriers, concentrated, washed and formulated with a continuous-flow centrifuge-based cell processing system, and then aliquoted with a cell filling system. Compared with 2D planar culture, there are no significant differences in the quality of hMSCs harvested from 3D culture. We have also applied these dissolvable porous microcarriers to other popular cell types in the CGT sector; specifically, HEK293T cells and Vero cells have been cultivated to peak cell densities of 1.68 x 107 cells/mL and 1.08 x 107 cells/mL, respectively. This study provides a protocol for using a bioprocess engineering platform harnessing the characteristics of GMP-grade dissolvable microcarriers and advanced closed equipment to achieve the industrial-scale manufacturing of adherent cells.


Asunto(s)
Técnicas de Cultivo de Célula , Células Madre Mesenquimatosas , Animales , Chlorocebus aethiops , Humanos , Técnicas de Cultivo de Célula/métodos , Células HEK293 , Porosidad , Células Vero , Reactores Biológicos , Proliferación Celular , Diferenciación Celular
17.
Chembiochem ; 24(17): e202300342, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37357819

RESUMEN

Nucleoside natural products show diverse biological activities and serve as leads for various application purposes, including human and veterinary medicine and agriculture. Studies in the past decade revealed that these nucleosides are biosynthesized through divergent mechanisms, in which early steps of the pathways can be classified into two types (C5' oxidation and C5' radical extension), while the structural diversity is created by downstream tailoring enzymes. Based on this biosynthetic logic, we investigated the genome mining discovery potentials of these nucleosides using the two enzymes representing the two types of C5' modifications: LipL-type α-ketoglutarate (α-KG) and Fe-dependent oxygenases and NikJ-type radical S-adenosyl-L-methionine (SAM) enzymes. The results suggest that this approach allows discovery of putative nucleoside biosynthetic gene clusters (BGCs) and the prediction of the core nucleoside structures. The results also revealed the distribution of these pathways in nature and implied the possibility of future genome mining discovery of novel nucleoside natural products.


Asunto(s)
Productos Biológicos , Nucleósidos , Humanos , Nucleósidos/química , Productos Biológicos/química , Oxidación-Reducción , Vías Biosintéticas/genética
18.
Biomaterials ; 298: 122111, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37141647

RESUMEN

Hematopoietic stem cells (HSCs) are adult multipotential stem cells with the capacity to differentiate into all blood cells and immune cells, which are essential for maintaining hematopoietic homeostasis throughout the lifespan and reconstituting damaged hematopoietic system after myeloablation. However, the clinical application of HSCs is hindered by the imbalance of its self-renewal and differentiation during in vitro culture. Considering the fact that HSC fate is uniquely determined by natural bone marrow microenvironment, various elaborate cues in this hematopoietic micro-niche provide an excellent reference for the regulation of HSCs. Inspired by the bone marrow extracellular matrix (ECM) network, we designed degradable scaffolds by orchestrating the physical parameters to investigate the decoupling effects of Young's modulus and pore size of three-dimensional (3D) matrix materials on the fate of hematopoietic stem and progenitor cells (HSPCs). We ascertained that the scaffold with larger pore size (80 µm) and higher Young's modulus (70 kPa) was more favorable for HSPCs proliferation and the maintenance of stemness related phenotypes. Through in vivo transplantation, we further validated that scaffolds with higher Young's modulus were more propitious in maintaining the hematopoietic function of HSPCs. We systematically screened an optimized scaffold for HSPC culture which could significantly improve the cell function and self-renewal ability compared with traditional two-dimensional (2D) culture. Together, these results indicate the important role of biophysical cues in regulating HSC fate and pave the way for the parameter design of 3D HSC culture system.


Asunto(s)
Señales (Psicología) , Células Madre Hematopoyéticas , Médula Ósea , Hematopoyesis , Diferenciación Celular , Nicho de Células Madre
19.
J Dairy Sci ; 106(6): 4366-4379, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37059660

RESUMEN

Misregulation of spermatogenesis transcription factors (TF) in hybrids can lead to misexpression, which is a mechanism for hybrid male sterility (HMS). We used dzo (male offspring of Bos taurus ♂ × Bos grunniens ♀) in bovines to investigate the relationship of the key TF with HMS via RNA sequencing and assay for transposase-accessible chromatin with high-throughput sequencing analyses. RNA sequencing showed that the widespread misexpression in dzo was associated with spermatogenesis-related genes and somatic or progenitor genes. The transition from leptotene or zygotene spermatocytes to pachytene spermatocytes may be the key stage for meiosis arrest in dzo. The analysis of TF-binding motif enrichment revealed that the male meiosis-specific master TF MYB proto-oncogene like 1 (MYBL1, known as A-MYB) motif was enriched on the promoters of downregulated pachytene spermatocyte genes in dzo. Assay for transposase-accessible chromatin with high-throughput sequencing revealed that TF-binding sites for MYBL1, nuclear transcription factor Y, and regulatory factor X were enriched in the low-chromatin accessibility region of dzo. The target genes of the MYBL1-binding motif were associated with meiosis-specific genes and significantly downregulated in dzo testis. The transcription factor MYBL1 may be the candidate master regulator for pachytene spermatocyte genes dysregulated in interspecific HMS dzo. This study reported that a few upstream TF regulation changes might exert a cascading effect downstream in a regulatory network as a mechanism for HMS.


Asunto(s)
Espermatocitos , Factores de Transcripción , Bovinos , Masculino , Animales , Espermatocitos/fisiología , Factores de Transcripción/genética , Espermatogénesis , Testículo , Cromatina
20.
Nat Commun ; 14(1): 2207, 2023 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-37072407

RESUMEN

Limited numbers of available hematopoietic stem cells (HSCs) limit the widespread use of HSC-based therapies. Expansion systems for functional heterogenous HSCs remain to be optimized. Here, we present a convenient strategy for human HSC expansion based on a biomimetic Microniche. After demonstrating the expansion of HSC from different sources, we find that our Microniche-based system expands the therapeutically attractive megakaryocyte-biased HSC. We demonstrate scalable HSC expansion by applying this strategy in a stirred bioreactor. Moreover, we identify that the functional human megakaryocyte-biased HSCs are enriched in the CD34+CD38-CD45RA-CD90+CD49f lowCD62L-CD133+ subpopulation. Specifically, the expansion of megakaryocyte-biased HSCs is supported by a biomimetic niche-like microenvironment, which generates a suitable cytokine milieu and supplies the appropriate physical scaffolding. Thus, beyond clarifying the existence and immuno-phenotype of human megakaryocyte-biased HSC, our study demonstrates a flexible human HSC expansion strategy that could help realize the strong clinical promise of HSC-based therapies.


Asunto(s)
Biomimética , Megacariocitos , Humanos , Células Madre Hematopoyéticas , Antígenos CD34 , Antígenos Comunes de Leucocito
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA