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1.
Curr Res Food Sci ; 9: 100824, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39263207

RESUMEN

In recent years, there has been a burgeoning interest in the utilization of microbial exopolysaccharides (EPS) because of the added advantage of their renewable, biocompatible, and biodegradable nature in addition to intended applications. The endowed properties of bacterial EPS make them valuable candidates for a wide array of industrial applications. Modification of native EPS is known to enhance various physico-chemical and functional properties. Various modifications such as physical, chemical, biological, and enzymatic modifications were practiced improving the bioactivity of EPS. This paper comprehensively aims to review the most recent chemical modification techniques employed to modify the physico-chemical and functional changes of bacterial EPS in comparison with the unmodified forms. Chemical modification entails strategic alterations to the structure and properties of EPS through various synthetic and semi-synthetic methodologies. Emphasis is given to the antioxidant potential and functional role of these EPS derivatives in human health. Antioxidant properties reveal a significant augmentation in activity compared to their native counterparts. Such enhancement holds a strong promise for potential benefits and therapeutic applications. Chemical derivatives of EPS with overwhelming functional benefits could surely encourage EPS application, particularly as potential hydrocolloids in industrial and biomedical contexts.

2.
ACS Biomater Sci Eng ; 10(4): 2510-2522, 2024 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-38466622

RESUMEN

Theranostic systems, which integrate therapy and diagnosis into a single platform, have gained significant attention as a promising approach for noninvasive cancer treatment. The field of image-guided therapy has revolutionized real-time tumor detection, and within this domain, plasmonic nanostructures have garnered significant attention. These structures possess unique localized surface plasmon resonance (LSPR), allowing for enhanced absorption in the near-infrared (NIR) range. By leveraging the heat generated from plasmonic nanoparticles upon NIR irradiation, target cancer cells can be effectively eradicated. This study introduces a plasmonic gold dogbone-nanorattle (AuDB NRT) structure that exhibits broad absorption in the NIR region and demonstrates a photothermal conversion efficiency of 35.29%. When exposed to an NIR laser, the AuDB NRTs generate heat, achieving a maximum temperature rise of 38 °C at a concentration of 200 µg/mL and a laser power density of 3 W/cm2. Additionally, the AuDB NRTs possess intrinsic electromagnetic hotspots that amplify the signal of a Raman reporter molecule, making them an excellent probe for surface-enhanced Raman scattering-based bioimaging of cancer cells. To improve the biocompatibility of the nanorattles, the AuDB NRTs were conjugated with mPEG-thiol and successfully encapsulated into cationic dextrin nanoparticles (CD NPs). Biocompatibility tests were performed on HEK 293 A and MCF-7 cell lines, revealing high cell viability when exposed to AuDB NRT-CD NPs. Remarkably, even at a low laser power density of 1 W/cm2, the application of the NIR laser resulted in a remarkable 80% cell death in cells treated with a nanocomposite concentration of 100 µg/mL. Further investigation elucidated that the cell death induced by photothermal heat followed an apoptotic mechanism. Overall, our findings highlight the significant potential of the prepared nanocomposite for cancer theranostics, combining effective photothermal therapy along with the ability to image cancer cells.


Asunto(s)
Nanocompuestos , Nanopartículas , Neoplasias , Humanos , Oro/farmacología , Oro/química , Dextrinas , Nanomedicina Teranóstica/métodos , Células HEK293 , Nanopartículas/uso terapéutico , Neoplasias/terapia
3.
RSC Chem Biol ; 5(3): 249-261, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38456040

RESUMEN

Intracellular protein delivery shows promise as a selective and specific approach to cancer therapy. However, a major challenge is posed by delivering proteins into the target cells. Despite the development of nanoparticle (NP)-based approaches, a versatile and biocompatible delivery system that can deliver active therapeutic cargo into the cytosol while escaping endosome degradation remains elusive. In order to overcome these challenges, a polymeric nanocarrier was prepared using cationic dextrin (CD), a biocompatible and biodegradable polymer, to encapsulate and deliver cytochrome C (Cyt C), a therapeutic protein. The challenge of endosomal escape of the nanoparticles was addressed by co-delivering the synthesized NP construct with chloroquine, which enhances the endosomal escape of the therapeutic protein. No toxicity was observed for both CD NPs and chloroquine at the concentration tested in this study. Spectroscopic investigations confirmed that the delivered protein, Cyt C, was structurally and functionally active. Additionally, the delivered Cyt C was able to induce apoptosis by causing depolarization of the mitochondrial membrane in HeLa cells, as evidenced by flow cytometry and microscopic observations. Our findings demonstrate that an engineered delivery system using CD NPs is a promising platform in nanomedicine for protein delivery applications.

4.
Sci Total Environ ; 921: 171051, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38382616

RESUMEN

Glyphosate (Gly) is a massively utilized toxic herbicide exceeding its statutory restrictions, causing adverse environmental and health impacts. Engineered nanomaterials, even though are integral to remediate Gly, their practical use is limited due to time and energy driven purifications, and negative environmental impacts. Here, a 3D wide area (~1.6 ± 0.4 cm2) Cu2O nanoparticle supported biotemplate is designed using fish-scale wastes as a sustainable approach for the ultra-efficient and selective hand-remediation of Gly from real-time samples from agro-farms. While the innate metal binding and reducing ability of collagenous scales aided self-synthesis cum grafting of Cu2O, the selective binding potential of Cu2O to Gly facilitated its hand-retrieval; as assessed using optical characterizations, Fourier transform infrared spectroscopy, thermogravimetric analysis and liquid chromatography mass spectrometry. Optimization studies revealed extractions of diverse pay-loads of Gly between 0.1 µg/mL to 40 µg/mL per 80 mg biotemplate grafted with ~6.354 µg of sub-5 nm Cu2O and was exponential to the number of Cu2O@biotemplates. Even though pH and surfactant didn't have any impact on the adsorption of Gly to the Cu2O@biotemplates, increase in the ionic strength led to a drastic increase in the adsorption. Density function theory simulations unveiled the involvement of phosphonic and carboxylic groups of Gly for interaction with Cu2O with a bond length of 1.826 Å and 1.833 Å, respectively. Overall, our sustainably generated, cost-efficient, hand-retrievable Cu2O supported biotemplate can be generalized to extract diverse organophosphorus toxins from agro-farms and other sewage embodiments. SYNOPSIS: Glyphosate is an excessively applied herbicide with potent health hazards and carcinogenicity. Thus, a hand removable Cu2O-supported biotemplate to selectively and efficiently remediate glyphosate from irrigation water is developed.


Asunto(s)
Glifosato , Herbicidas , Animales , Herbicidas/química , Agua , Tensoactivos , Bioingeniería
5.
RNA Biol ; 21(1): 1-14, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38329136

RESUMEN

In recent years, advances in biomedicine have revealed an important role for post-transcriptional mechanisms of gene expression regulation in pathologic conditions. In cancer in general and leukaemia specifically, RNA binding proteins have emerged as important regulator of RNA homoeostasis that are often dysregulated in the disease state. Having established the importance of these pathogenetic mechanisms, there have been a number of efforts to target RNA binding proteins using oligonucleotide-based strategies, as well as with small organic molecules. The field is at an exciting inflection point with the convergence of biomedical knowledge, small molecule screening strategies and improved chemical methods for synthesis and construction of sophisticated small molecules. Here, we review the mechanisms of post-transcriptional gene regulation, specifically in leukaemia, current small-molecule based efforts to target RNA binding proteins, and future prospects.


Asunto(s)
Neoplasias Hematológicas , Leucemia , Humanos , Regulación de la Expresión Génica , ARN/genética , Neoplasias Hematológicas/genética , Leucemia/genética , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo
6.
Blood Adv ; 8(2): 261-275, 2024 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-38048400

RESUMEN

ABSTRACT: RNA-binding proteins (RBPs) are emerging as a novel class of therapeutic targets in cancer, including in leukemia, given their important role in posttranscriptional gene regulation, and have the unexplored potential to be combined with existing therapies. The RBP insulin-like growth factor 2 messenger RNA-binding protein 3 (IGF2BP3) has been found to be a critical regulator of MLL-AF4 leukemogenesis and represents a promising therapeutic target. Here, we study the combined effects of targeting IGF2BP3 and menin-MLL interaction in MLL-AF4-driven leukemia in vitro and in vivo, using genetic inhibition with CRISPR-Cas9-mediated deletion of Igf2bp3 and pharmacologic inhibition of the menin-MLL interaction with multiple commercially available inhibitors. Depletion of Igf2bp3 sensitized MLL-AF4 leukemia to the effects of menin-MLL inhibition on cell growth and leukemic initiating cells in vitro. Mechanistically, we found that both Igf2bp3 depletion and menin-MLL inhibition led to increased differentiation in vitro and in vivo, seen in functional readouts and by gene expression analyses. IGF2BP3 knockdown had a greater effect on increasing survival and attenuating disease than pharmacologic menin-MLL inhibition with small molecule MI-503 alone and showed enhanced antileukemic effects in combination. Our work shows that IGF2BP3 is an oncogenic amplifier of MLL-AF4-mediated leukemogenesis and a potent therapeutic target, providing a paradigm for targeting leukemia at both the transcriptional and posttranscriptional level.


Asunto(s)
Leucemia , Proteína de la Leucemia Mieloide-Linfoide , Humanos , Proteína de la Leucemia Mieloide-Linfoide/genética , Proteína de la Leucemia Mieloide-Linfoide/metabolismo , Leucemia/tratamiento farmacológico , Leucemia/genética , Leucemia/metabolismo , Factores de Transcripción , Diferenciación Celular , Proteínas de Fusión Oncogénica/genética
7.
J Mater Chem B ; 11(43): 10418-10432, 2023 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-37877327

RESUMEN

Medical implants are frequently used in medicine and reconstructive surgery to treat various pathological and anatomical conditions. However, over time, biofilm formation on the surface of these implants can cause recurrent infections and subsequent inflammatory responses in the host, resulting in tissue damage, necrosis, and re-hospitalization. To address these implant-associated infections, the best approach is to create antimicrobial coatings. Here, we report the fabrication of a biocompatible, non-leaching, and contact-based antibacterial coating for implants using quaternary pullulan functionalized MoS2 (MCP) glycosheets. The cationic MCP glycosheets were coated on the surfaces of polydopamine-modified stainless steel and polyvinyl fluoride substrates through a simple process of electrostatic interaction. The developed coating showed excellent antibacterial activity (>99.5%) against E. coli and S. aureus that remained stable over 30 days without leaching out of the substrates and retained its antibacterial activity. MCP-coated implants did not induce any acute or sub-chronic toxicity to mammalian cells, both in vitro and in vivo. Furthermore, MCP coating prevented S. aureus colonization on stainless steel implants in a mouse model of implant-associated infection. The MCP coating developed in this study represents a simple, safe, and effective antibacterial coating for preventing implant-associated infections.


Asunto(s)
Molibdeno , Staphylococcus aureus , Ratones , Animales , Molibdeno/farmacología , Escherichia coli , Acero Inoxidable , Biopelículas , Antibacterianos/farmacología , Mamíferos
8.
Cancers (Basel) ; 15(18)2023 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-37760460

RESUMEN

BACKGROUND: Although IGF2BP3 has been implicated in tumorigenesis and poor outcomes in multiple cancers, its role in soft-tissue sarcoma (STS) remains unknown. Preliminary data have suggested an association with IGF2BP3 expression among patients with well-differentiated/dedifferentiated liposarcoma (WD/DD LPS), a disease where molecular risk stratification is lacking. METHODS: We examined the survival associations of IGF2BP3 via univariate and multivariate Cox regression in three unique datasets: (1) the Cancer Genome Atlas (TCGA), (2) an in-house gene microarray, and (3) an in-house tissue microarray (TMA). A fourth dataset, representing an independent in-house TMA, was used for validation. RESULTS: Within the TCGA dataset, IGF2BP3 expression was a poor prognostic factor uniquely in DD LPS (OS 1.6 vs. 5.0 years, p = 0.009). Within the microarray dataset, IGF2BP3 expression in WD/DD LPS was associated with worse survival (OS 7.7 vs. 21.5 years, p = 0.02). IGF2BP3 protein expression also portended worse survival in WD/DD LPS (OS 3.7 vs. 13.8 years, p < 0.001), which was confirmed in our validation cohort (OS 2.7 vs. 14.9 years, p < 0.001). In the multivariate model, IGF2BP3 was an independent risk factor for OS, (HR 2.55, p = 0.034). CONCLUSION: IGF2BP3 is highly expressed in a subset of WD/DD LPS. Across independent datasets, IGF2BP3 is also a biomarker of disease progression and worse survival.

9.
J Exp Clin Cancer Res ; 42(1): 231, 2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37670323

RESUMEN

BACKGROUND: Acute lymphoblastic leukemia (ALL) is the most common pediatric hematological malignancy, with ETV6::RUNX1 being the most prevalent translocation whose exact pathogenesis remains unclear. IGF2BP1 (Insulin-like Growth Factor 2 Binding Protein 1) is an oncofetal RNA binding protein seen to be specifically overexpressed in ETV6::RUNX1 positive B-ALL. In this study, we have studied the mechanistic role of IGF2BP1 in leukemogenesis and its synergism with the ETV6::RUNX1 fusion protein. METHODS: Gene expression was analyzed from patient bone marrow RNA using Real Time RT-qPCR. Knockout cell lines were created using CRISPR-Cas9 based lentiviral vectors. RNA-Seq and RNA Immunoprecipitation sequencing (RIP-Seq) after IGF2BP1 pulldown were performed using the Illumina platform. Mouse experiments were done by retroviral overexpression of donor HSCs followed by lethal irradiation of recipients using a bone marrow transplant model. RESULTS: We observed specific overexpression of IGF2BP1 in ETV6::RUNX1 positive patients in an Indian cohort of pediatric ALL (n=167) with a positive correlation with prednisolone resistance. IGF2BP1 expression was essential for tumor cell survival in multiple ETV6::RUNX1 positive B-ALL cell lines. Integrated analysis of transcriptome sequencing after IGF2BP1 knockout and RIP-Seq after IGF2BP1 pulldown in Reh cell line revealed that IGF2BP1 targets encompass multiple pro-oncogenic signalling pathways including TNFα/NFκB and PI3K-Akt pathways. These pathways were also dysregulated in primary ETV6::RUNX1 positive B-ALL patient samples from our center as well as in public B-ALL patient datasets. IGF2BP1 showed binding and stabilization of the ETV6::RUNX1 fusion transcript itself. This positive feedback loop led to constitutive dysregulation of several oncogenic pathways. Enforced co-expression of ETV6::RUNX1 and IGF2BP1 in mouse bone marrow resulted in marrow hypercellularity which was characterized by multi-lineage progenitor expansion and strong Ki67 positivity. This pre-leukemic phenotype confirmed their synergism in-vivo. Clonal expansion of cells overexpressing both ETV6::RUNX1 and IGF2BP1 was clearly observed. These mice also developed splenomegaly indicating extramedullary hematopoiesis. CONCLUSION: Our data suggest a combined impact of the ETV6::RUNX1 fusion protein and RNA binding protein, IGF2BP1 in activating multiple oncogenic pathways in B-ALL which makes IGF2BP1 and these pathways as attractive therapeutic targets and biomarkers.


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Animales , Ratones , Subunidad alfa 2 del Factor de Unión al Sitio Principal , Ratones Noqueados , Fosfatidilinositol 3-Quinasas , Proteína ETS de Variante de Translocación 6
10.
ACS Appl Bio Mater ; 6(10): 3946-3958, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37698377

RESUMEN

Primary bone tumors such as Ewing sarcoma, osteosarcoma, and chondrosarcoma, secondary bone tumors developed from progressive malignancies, and metastasized bone tumors are more prevalent and studied descriptively through biology and medical research. Less than 0.2% of cancer diagnoses are caused by rare bone-originating tumors, which despite being rare are particularly difficult due to their high death rates and substantial disease burden. A giant cell tumor of bone (GCTB) is an intramurally invasive but rare and benign type of bone tumor, which seldom metastasizes. The most often prescribed medication for GCTB is Denosumab, a RANKL (receptor activator of nuclear factor κB ligand) inhibitor. Because pharmaceutical drug companies rely on two-dimensional and animal models, current approaches for investigating the diverse nature of tumors are insufficient. Cell line based medication effectiveness and toxicity studies cannot predict tumor response to antitumor medicines. It has already been investigated in detail why molecular pathways do not reproduce in vitro, a phenomenon known as flat biology. Due to physiological differences between human beings and animals, animal models do not succeed in identifying side effects of the treatment, emulating metastatic growth, and establishing the link between cancer and the immune system. This review summarizes and discusses GCTB, the disease, its cellular composition, various bone tumor models, and their properties and utilization in research. As a result, this study delves deep into in vitro testing, which is vital for scientists and physicians in various fields, including pharmacology, preclinical investigations, tissue engineering, and regenerative medicine.

11.
ACS Appl Mater Interfaces ; 15(33): 39081-39098, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37566573

RESUMEN

Recent developments in nanomaterials with programmable optical responses and their capacity to modulate the photothermal effect induced by an extrinsic source of light have elevated plasmonic photothermal therapy (PPTT) to the status of a favored treatment for a variety of malignancies. However, the low penetration depth of near-infrared-I (NIR-I) lights and the need to expose the human body to a high laser power density in PPTT have restricted its clinical translation for cancer therapy. Most nanostructures reported to date exhibit limited performance due to (i) activity only in the NIR-I region, (ii) the use of intense laser, (iii) need of large concentration of nanomaterials, or (iv) prolonged exposure times to achieve the optimal hyperthermia state for cancer phototherapy. To overcome these shortcomings in plasmonic nanomaterials, we report a bimetallic palladium nanocapsule (Pd Ncap)─with a solid gold bead as its core and a thin, perforated palladium shell─with extinction both in the NIR-I as well as the NIR-II region for PPTT applications toward cancer therapy. The Pd Ncap demonstrated exceptional photothermal stability with a photothermal conversion efficiency of ∼49% at the NIR-II (1064 nm) wavelength region at a very low laser power density of 0.5 W/cm2. The nanocapsules were further surface-functionalized with Herceptin (Pd Ncap-Her) to target the breast cancer cell line SK-BR-3 and exploited for in vitro PPTT applications using NIR-II light. Pd Ncap-Her caused more than 98% cell death at a concentration of just 50 µg/mL and a laser power density of 0.5 W/cm2 with an output power of only 100 mW. Flow cytometric and microscopic analyses revealed that Pd Ncap-Her-induced apoptosis in the treated cancer cells during PPTT. Additionally, Pd Ncaps were found to have reactive oxygen species (ROS) scavenging ability, which can potentially reduce the damage to cells or tissues from ROS produced during PPTT. Also, Pd Ncap demonstrated excellent in vivo biocompatibility and was highly efficient in photothermally ablating tumors in mice. With a high photothermal conversion and killing efficiency at very low nanoparticle concentrations and laser power densities, the current nanostructure can operate as an effective phototherapeutic agent for the treatment of different cancers with ROS-protecting ability.


Asunto(s)
Hipertermia Inducida , Nanocápsulas , Nanopartículas , Neoplasias , Humanos , Femenino , Animales , Ratones , Fototerapia , Paladio/farmacología , Paladio/química , Terapia Fototérmica , Especies Reactivas de Oxígeno , Neoplasias/terapia , Nanopartículas/química , Línea Celular Tumoral
12.
Biotechnol Bioeng ; 120(8): 2117-2132, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37366303

RESUMEN

Among several types of brain cancers, glioblastoma multiforme (GBM) is a terminal and aggressive disease with a median survival of 15 months despite the most intensive surgery and chemotherapy. Preclinical models that accurately reproduce the tumor microenvironment are vital for developing new therapeutic alternatives. Understanding the complicated interactions between cells and their surroundings is essential to comprehend the tumor's microenvironment, however the monolayer cell culture approach falls short. Numerous approaches are used to develop GBM cells into tumor spheroids, while scaffold-based spheroids provides the opportunity to investigate the synergies between cells as well as cells and the matrix. This review summarizes the development of various scaffold-based GBM spheroid models and the prospective for their use as drug testing systems.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Evaluación Preclínica de Medicamentos , Estudios Prospectivos , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Microambiente Tumoral , Línea Celular Tumoral , Esferoides Celulares/patología
13.
Cell Biol Int ; 47(7): 1229-1246, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36934421

RESUMEN

Mutations in the form of insertions and deletions (INDEL) in the calreticulin gene lead to essential thrombocythemia (ET) which is characterized by the formation of thrombosis. However, the connection between calreticulin INDEL and ET remains largely elusive. Through combined molecular dynamics simulation, clustered regularly interspaced short palindromic repeats (CRISPR) and calcium imaging studies on the wild type and mutated isoforms of calreticulin, the mechanism underlying the calreticulin INDEL induced ET was investigated at the molecular level. Our results demonstrate that mutations in exon-9 could lead to significant conformational variations of calreticulin structure and thereby reducing its interaction with calcium ions due to decreased electrostatic contributions. The consequence of mutations on calreticulin's structural integrity was revealed by identifying the key residues and their roles in calcium binding. Furthermore, mutations implemented by CRISPR-Cas9 in exon-9 showed diminished calcium signaling in HEK-293T cells, which agree well with our in-silico findings. The current study might help in understanding the variations of molecular interactions between calreticulin's exon-9 and calcium ions during physiological and pathological conditions. The results might also provide useful information for designing novel therapeutic approaches targeting ET.


Asunto(s)
Señalización del Calcio , Calreticulina , Trastornos Mieloproliferativos , Trombocitemia Esencial , Humanos , Calcio/metabolismo , Calreticulina/genética , Calreticulina/metabolismo , Mutación , Trastornos Mieloproliferativos/patología , Neoplasias , Trombocitemia Esencial/patología
14.
Food Chem ; 405(Pt A): 134798, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-36370564

RESUMEN

This study involves the preparation of PLA/PBAT composite blend films incorporated with TiO2 and varying concentrations of cinnamon essential oil. The films were characterised for optical and mechanical properties, chemical composition, thermo-stability, surface hydrophobicity, inhibition of biofilm formation, anti-microbial efficiency against S. aureus and E. coli, and application on cheese. The thickness of the films increased with the increase in cinnamon oil concentration along with the water contact angle degree and highest UV-barrier properties with the PLA-PBAT-TiO2-7 %Cinn film. The best anti-bacterial activity was seen in the PLA-PBAT-TiO2-7 %Cinn film against S. aureus and E. coli. The cheese packed in PLA-PBAT-TiO2-7 %Cinn film has shown the least weight loss and enhanced antibacterial activity against E. coli for 12 days of storage. The use of cinnamon oil-loaded TiO2 incorporated in films showed positive effects on the shelf life, quality, and safety of a food product and has a high potential for use commercially.


Asunto(s)
Queso , Nanocompuestos , Aceites Volátiles , Cinnamomum zeylanicum/química , Aceites Volátiles/farmacología , Embalaje de Alimentos , Staphylococcus aureus , Escherichia coli , Poliésteres/química , Nanocompuestos/química , Antibacterianos/farmacología , Antibacterianos/química
15.
Leukemia ; 36(1): 68-79, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34321607

RESUMEN

Despite recent advances in therapeutic approaches, patients with MLL-rearranged leukemia still have poor outcomes. Here, we find that the RNA-binding protein IGF2BP3, which is overexpressed in MLL-translocated leukemia, strongly amplifies MLL-Af4-mediated leukemogenesis. Deletion of Igf2bp3 significantly increases the survival of mice with MLL-Af4-driven leukemia and greatly attenuates disease, with a minimal impact on baseline hematopoiesis. At the cellular level, MLL-Af4 leukemia-initiating cells require Igf2bp3 for their function in leukemogenesis. At the molecular level, IGF2BP3 regulates a complex posttranscriptional operon governing leukemia cell survival and proliferation. IGF2BP3-targeted mRNA transcripts include important MLL-Af4-induced genes, such as those in the Hoxa locus, and the Ras signaling pathway. Targeting of transcripts by IGF2BP3 regulates both steady-state mRNA levels and, unexpectedly, pre-mRNA splicing. Together, our findings show that IGF2BP3 represents an attractive therapeutic target in this disease, providing important insights into mechanisms of posttranscriptional regulation in leukemia.


Asunto(s)
Carcinogénesis/patología , Proteínas de Unión al ADN/genética , Regulación Leucémica de la Expresión Génica , N-Metiltransferasa de Histona-Lisina/genética , Leucemia Experimental/patología , Proteína de la Leucemia Mieloide-Linfoide/genética , Proteínas Nucleares/genética , Proteínas de Fusión Oncogénica/genética , Proteínas de Unión al ARN/fisiología , Animales , Apoptosis , Carcinogénesis/genética , Carcinogénesis/metabolismo , Proliferación Celular , Femenino , Leucemia Experimental/etiología , Leucemia Experimental/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados
16.
FEBS J ; 289(12): 3393-3415, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-33866670

RESUMEN

The mammalian sirtuin family consists of seven proteins, three of which (SIRT3, SIRT4, and SIRT5) localise specifically within mitochondria and preserve mitochondrial function and homeostasis. Mitochondrial sirtuins are involved in diverse functions such as deacetylation, ADP-ribosylation, demalonylation and desuccinylation, thus affecting various aspects of cell fate. Intriguingly, mitochondrial sirtuins are able to manage these delicate processes with accuracy mediated by crosstalk between the nucleus and mitochondria. Previous studies have provided ample information about their substrates and targets, whereas less is known about their role in cancer and stem cells. Here, we review and discuss recent advances in our understanding of the structural and functional properties of mitochondrial sirtuins, including their targets in cancer and stem cells. These advances could help to improve the understanding of their interplay with signalling cascades and pathways, leading to new avenues for developing novel drugs for sirtuin-related disease treatments. We also highlight the complex network of mitochondrial sirtuins in cancer and stem cells, which may be important in deciphering the molecular mechanism for their activation and inhibition.


Asunto(s)
Neoplasias , Sirtuinas , Animales , Mamíferos/metabolismo , Mitocondrias/metabolismo , Proteínas Mitocondriales/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Sirtuinas/genética , Sirtuinas/metabolismo , Células Madre/metabolismo
17.
Langmuir ; 37(36): 10818-10826, 2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34470217

RESUMEN

Direct visualization of the dynamic events in lysosomes during drug-mediated programmed cell death (apoptosis) is a great challenge. This is due to the lack of resolving power of a conventional microscope and also the unavailability of a suitable multimodal probe that simultaneously can carry the drug with high loading capacity and ensure its specific internalization into lysosomes. In this work, using super-resolution microscopy, we observed the lysosomal expansion during apoptosis that was treated with epigallocatechin gallate (EGCG) conjugated to bovine serum albumin (BSA). Albumin protein is known to internalize into lysosomes via endocytosis, thus helping in the specific delivery of EGCG to the lysosomal compartment. The conjugation of EGCG to BSA not only helped in increasing the killing efficiency of cancer cells but it also reduces the side effects and produces minimal reactive oxygen species. The decrease in local viscosity helped in lysosomal expansion during apoptosis.


Asunto(s)
Catequina , Microscopía , Apoptosis , Catequina/análogos & derivados , Lisosomas , Especies Reactivas de Oxígeno
18.
Sci Rep ; 11(1): 13158, 2021 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-34162911

RESUMEN

Post-transcriptional gene regulation, including that by RNA binding proteins (RBPs), has recently been described as an important mechanism in cancer. We had previously identified a set of RBPs that were highly dysregulated in B-cell acute lymphoblastic leukemia (B-ALL) with MLL translocations, which carry a poor prognosis. Here, we sought to functionally characterize these dysregulated RBP genes by performing a focused CRISPR dropout screen in B-ALL cell lines, finding dependencies on several genes including EIF3E, EPRS and USO1. Validating our findings, CRISPR/Cas9-mediated disruption of USO1 in MLL-translocated B-ALL cells reduced cell growth, promoted cell death, and altered the cell cycle. Transcriptomic analysis of USO1-deficient cells revealed alterations in pathways related to mTOR signaling, RNA metabolism, and targets of MYC. In addition, USO1-regulated genes from these experimental samples were significantly and concordantly correlated with USO1 expression in primary samples collected from B-ALL patients. Lastly, we found that loss of Uso1 inhibited colony formation of MLL-transformed in primary bone marrow cells from Cas9-EGFP mice. Together, our findings demonstrate an approach to performing focused sub-genomic CRISPR screens and highlight a putative RBP vulnerability in MLL-translocated B-ALL, thus identifying potential therapeutic targets in this disease.


Asunto(s)
Sistemas CRISPR-Cas , Proteínas de la Matriz de Golgi/fisiología , Proteína de la Leucemia Mieloide-Linfoide/fisiología , Proteínas de Neoplasias/fisiología , Proteínas de Fusión Oncogénica/fisiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas de Transporte Vesicular/fisiología , Animales , Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Regulación Leucémica de la Expresión Génica , Genes Reporteros , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Proteínas de la Matriz de Golgi/genética , Homeostasis , Humanos , Ratones , Ratones Endogámicos C57BL , Proteína de la Leucemia Mieloide-Linfoide/genética , Proteínas de Neoplasias/genética , Proteínas de Fusión Oncogénica/genética , Procesamiento Postranscripcional del ARN , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Transgenes , Translocación Genética , Ensayo de Tumor de Célula Madre , Proteínas de Transporte Vesicular/genética
19.
Mar Drugs ; 19(6)2021 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-34071764

RESUMEN

This study aims to explore novel extraction technologies (ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), ultrasound-microwave-assisted extraction (UMAE), hydrothermal-assisted extraction (HAE) and high-pressure-assisted extraction (HPAE)) and extraction time post-treatment (0 and 24 h) for the recovery of phytochemicals and associated antioxidant properties from Fucus vesiculosus and Pelvetia canaliculata. When using fixed extraction conditions (solvent: 50% ethanol; extraction time: 10 min; algae/solvent ratio: 1/10) for all the novel technologies, UAE generated extracts with the highest phytochemical contents from both macroalgae. The highest yields of compounds extracted from F. vesiculosus using UAE were: total phenolic content (445.0 ± 4.6 mg gallic acid equivalents/g), total phlorotannin content (362.9 ± 3.7 mg phloroglucinol equivalents/g), total flavonoid content (286.3 ± 7.8 mg quercetin equivalents/g) and total tannin content (189.1 ± 4.4 mg catechin equivalents/g). In the case of the antioxidant activities, the highest DPPH activities were achieved by UAE and UMAE from both macroalgae, while no clear pattern was recorded in the case of FRAP activities. The highest DPPH scavenging activities (112.5 ± 0.7 mg trolox equivalents/g) and FRAP activities (284.8 ± 2.2 mg trolox equivalents/g) were achieved from F. vesiculosus. Following the extraction treatment, an additional storage post-extraction (24 h) did not improve the yields of phytochemicals or antioxidant properties of the extracts.


Asunto(s)
Antioxidantes/aislamiento & purificación , Técnicas de Química Analítica/métodos , Phaeophyceae/química , Fitoquímicos/aislamiento & purificación , Polifenoles/aislamiento & purificación , Antioxidantes/análisis , Antioxidantes/química , Fucus/química , Calor , Microondas , Fitoquímicos/análisis , Fitoquímicos/química , Polifenoles/análisis , Polifenoles/química , Presión , Ondas Ultrasónicas , Agua
20.
ACS Appl Mater Interfaces ; 13(11): 12912-12927, 2021 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-33715350

RESUMEN

The current pandemic caused by SARS-CoV-2 has seen a widespread use of personal protective equipment, especially face masks. This has created the need to develop better and reusable protective masks with built-in antimicrobial, self-cleaning, and aerosol filtration properties to prevent the transmission of air-borne pathogens such as the coronaviruses. Herein, molybdenum disulfide (MoS2) nanosheets are used to prepare modified polycotton fabrics having excellent antibacterial activity and photothermal properties. Upon sunlight irradiation, the nanosheet-modified fabrics rapidly increased the surface temperature to ∼77 °C, making them ideal for sunlight-mediated self-disinfection. Complete self-disinfection of the nanosheet-modified fabric was achieved within 3 min of irradiation, making the fabrics favorably reusable upon self-disinfection. The nanosheet-modified fabrics maintained the antibacterial efficiency even after 60 washing cycles. Furthermore, the particle filtration efficiency of three-layered surgical masks was found to be significantly improved through incorporation of the MoS2-modified fabric as an additional layer of protective clothing, without compromising the breathability of the masks. The repurposed surgical masks could filter out around 97% of 200 nm particles and 96% of 100 nm particles, thus making them potentially useful for preventing the spread of coronaviruses (120 nm) by trapping them along with antibacterial protection against other airborne pathogens.


Asunto(s)
Antiinfecciosos/química , Disulfuros/química , Molibdeno/química , Nanoestructuras/química , Equipo de Protección Personal , Reciclaje , Antiinfecciosos/farmacología , COVID-19/prevención & control , COVID-19/virología , Escherichia coli/efectos de los fármacos , Escherichia coli/metabolismo , Glutatión/química , Humanos , Nanoestructuras/toxicidad , Oxidación-Reducción , Tamaño de la Partícula , Especies Reactivas de Oxígeno/metabolismo , SARS-CoV-2/aislamiento & purificación , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/metabolismo , Luz Solar , Temperatura
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