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1.
ACS Appl Mater Interfaces ; 16(7): 8538-8553, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38343191

RESUMO

Large osseous void, postsurgical neoplastic recurrence, and slow bone-cartilage repair rate raise an imperative need to develop functional scaffold in clinical osteosarcoma treatment. Herein, a bionic bilayer scaffold constituting croconaine dye-polyethylene glycol@sodium alginate hydrogel and poly(l-lactide)/hydroxyapatite polymer matrix is fabricated to simultaneously achieve a highly efficient killing of osteosarcoma and an accelerated osteochondral regeneration. First, biomimetic osteochondral structure along with adequate interfacial interaction of the bilayer scaffold provide a structural reinforcement for transverse osseointegration and osteochondral regeneration, as evidenced by upregulated specific expressions of collagen type-I, osteopontin, and runt-related transcription factor 2. Meanwhile, thermal ablation of the synthesized nanoparticles and mitochondrial dysfunction caused by continuously released hydroxyapatite induce residual tumor necrosis synergistically. To validate the capabilities of inhibiting tumor growth and promoting osteochondral regeneration of our proposed scaffold, a novel orthotopic osteosarcoma model simulating clinical treatment scenarios of bone tumors is established on rats. Based on amounts of in vitro and in vivo results, an effective killing of osteosarcoma and a suitable osteal-microenvironment modulation of such bionic bilayer composite scaffold are achieved, which provides insightful implications for photonic hyperthermia therapy against osteosarcoma and following osseous tissue regeneration.


Assuntos
Hipertermia Induzida , Osteossarcoma , Ratos , Animais , Alicerces Teciduais/química , Biônica , Materiais Biocompatíveis/química , Durapatita/química , Regeneração Óssea , Osteossarcoma/terapia , Microambiente Tumoral
3.
J Immunother Cancer ; 10(10)2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36283735

RESUMO

Downregulation of MHC class I (MHCI) molecules on tumor cells is recognized as a resistance mechanism of cancer immunotherapy. Given that MHCI molecules are potent regulators of immune responses, we postulated that the expression of MHCI by tumor cells influences systemic immune responses. Accordingly, mice-bearing MHCI-deficient tumor cells showed reduced tumor-associated extramedullary myelopoiesis in the spleen. Depletion of natural killer (NK) cells abrogated these differences, suggesting an integral role of immune-regulatory NK cells during tumor progression. Cytokine-profiling revealed an upregulation of TNF-α by NK cells in tumors and spleen in mice-bearing MHCI expressing tumors, and inhibition of TNF-α enhanced host myelopoiesis in mice receiving adoptive transfer of tumor-experienced NK cells. Our study highlights a critical role of NK cells beyond its identity as a killer lymphocyte and more importantly, the potential host responses to a localized tumor as determined by its MHCI expression.


Assuntos
Mielopoese , Neoplasias , Camundongos , Animais , Fator de Necrose Tumoral alfa , Células Matadoras Naturais , Antígenos de Histocompatibilidade Classe I
4.
Adv Mater ; 34(36): e2202044, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35785450

RESUMO

Engineering a proper immune response following biomaterial implantation is essential to bone tissue regeneration. Herein, a biomimetically hierarchical scaffold composed of deferoxamine@poly(ε-caprolactone) nanoparticles (DFO@PCL NPs), manganese carbonyl (MnCO) nanosheets, gelatin methacryloyl hydrogel, and a polylactide/hydroxyapatite (HA) matrix is fabricated to augment bone repair by facilitating the balance of the immune system and bone metabolism. First, a 3D printed stiff scaffold with a well-organized gradient structure mimics the cortical and cancellous bone tissues; meanwhile, an inside infusion of a soft hydrogel further endows the scaffold with characteristics of the extracellular matrix. A Fenton-like reaction between MnCO and endogenous hydrogen peroxide generated at the implant-tissue site triggers continuous release of carbon monoxide and Mn2+ , thus significantly lessening inflammatory response by upregulating the M2 phenotype of macrophages, which also secretes vascular endothelial growth factor to induce vascular formation. Through activating the hypoxia-inducible factor-1α pathway, Mn2+ and DFO@PCL NP further promote angiogenesis. Moreover, DFO inhibits osteoclast differentiation and synergistically collaborates with the osteoinductive activity of HA. Based on amounts of data in vitro and in vivo, strong immunomodulatory, intensive angiogenic, weak osteoclastogenic, and superior osteogenic abilities of such an osteoimmunity-regulating scaffold present a profound effect on improving bone regeneration, which puts forward a worthy base and positive enlightenment for large-scale bone defect repair.


Assuntos
Células-Tronco Mesenquimais , Alicerces Teciduais , Regeneração Óssea , Durapatita/química , Gelatina , Hidrogéis/metabolismo , Metacrilatos , Osteogênese , Engenharia Tecidual , Alicerces Teciduais/química , Fator A de Crescimento do Endotélio Vascular/metabolismo
5.
Proc Natl Acad Sci U S A ; 117(44): 27556-27565, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33077599

RESUMO

Tumor-associated macrophages (TAMs) continuously fine tune their immune modulatory properties, but how gene expression programs coordinate this immune cell plasticity is largely unknown. Selective mRNA translation, controlled by MNK1/MNK2 and mTOR pathways impinging on eIF4E, facilitates reshaping of proteomes without changes in abundance of corresponding mRNAs. Using polysome profiling developed for small samples we show that, during tumor growth, gene expression in TAMs is predominately modulated via mRNA-selective changes in translational efficiencies. These alterations in gene expression paralleled accumulation of antiinflammatory macrophages with augmented phosphorylation of eIF4E, a target of the MNK1 and MNK2 kinases, known to selectively modulate mRNA translation. Furthermore, suppression of the MNK2, but not the mTOR signaling pathway, reprogrammed antiinflammatory macrophages toward a proinflammatory phenotype with the ability to activate CD8+ T cells. Thus, selective changes of mRNA translation depending on MNK2 signaling represents a key node regulating macrophage antiinflammatory functions.


Assuntos
Macrófagos/imunologia , Neoplasias/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Técnicas de Cocultura , Modelos Animais de Doenças , Fator de Iniciação 4E em Eucariotos/genética , Fator de Iniciação 4E em Eucariotos/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/imunologia , Técnicas de Silenciamento de Genes , Humanos , Células MCF-7 , Macrófagos/metabolismo , Camundongos , Camundongos Transgênicos , Naftiridinas/farmacologia , Neoplasias/genética , Neoplasias/patologia , Fosforilação/genética , Fosforilação/imunologia , Cultura Primária de Células , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Evasão Tumoral/genética
6.
Artigo em Chinês | MEDLINE | ID: mdl-21033150

RESUMO

OBJECTIVE: To investigate the level of occupational exposure to 5-fluorouracil (5-Fu) in the pharmacy intravenous admixture service (PIVAS) of a hospital, and identify the sources of 5-Fu contamination. METHODS: The 5-Fu concentrations in air, on the surface of different areas in PIVAS and personal protective equipments were detected using UV-vis spectrophotometry. RESULTS: The 5-Fu in air could not be detected. The 5-Fu concentrations on five different surfaces of biological safety cabinets were (22.00 +/- 6.35), (13.99 +/- 2.46), (14.13 +/- 0.72), (7.25 +/- 1.19) and (9.87 +/- 1.23) ng/cm2, respectively, which were significantly higher than those [(3.14 +/- 0.04), (5.43 +/- 0.65), (2.26 +/- 0.17), (2.26 +/- 0.17) and (3.63 +/- 0.46) ng/cm2] of corresponding controls (P < 0.05 or P < 0.01). The 5-Fu concentrations of the floor under cabinets [(18.19 +/- 5.22) ng/cm2], the floor in front of cabinets [(10.25 +/- 2.57)ng/cm2], the office floor [(11.64 +/- 2.53) ng/cm2], the terrace floor [(99.89 +/- 14.06 ) ng/cm2], the floor beside trash can in dressing room [(24.54 +/- 0.23) ng/cm2] were significantly higher than those of control [(3.36 +/- 0.11 ) ng/cm2] (P < 0.05 or P < 0.01). The 5-Fu concentrations of the tables in preparation room [(7.22 +/- l.04) ng/cm2] and the tables in office [(11.81 +/- 1.18) ng/cm2] were significantly higher than those of control [(5.56 +/- 0.14) ng/cm2] (P < 0.05 or P < 0.01). The 5-Fu concentrations of the indoor handle in preparation room were significantly higher than those of controls (P < 0.05 or P < 0.01). 5-Fu concentrations on the surfaces of outdoor handle and floor beside door in preparation room were not significantly increased compared with controls (P > 0.05). The 5-Fu concentrations on the surfaces of infusion bags, transfer box, transfer trays were significantly higher than those of controls (P < 0.05). The differences of 5-Fu concentrations between outer and inner masks and controls were not significant (P > 0.05). The 5-Fu concentrations of gloves of preparing and checking staffs were significantly higher than those of controls (P < 0.05 or P < 0.01). CONCLUSION: The preparing and checking process of 5-Fu and the treatment of medical wastes are major sources of 5-Fu contamination.


Assuntos
Antineoplásicos/análise , Fluoruracila/análise , Exposição Ocupacional , Vias de Administração de Medicamentos , Humanos , Serviço de Farmácia Hospitalar
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