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1.
Int J Nanomedicine ; 19: 2755-2772, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525008

RESUMO

Purpose: The drug resistance and low response rates of immunotherapy limit its application. This study aimed to construct a new nanoparticle (CaCO3-polydopamine-polyethylenimine, CPP) to effectively deliver interleukin-12 (IL-12) and suppress cancer progress through immunotherapy. Methods: The size distribution of CPP and its zeta potential were measured using a Malvern Zetasizer Nano-ZS90. The morphology and electrophoresis tentative delay of CPP were analyzed using a JEM-1400 transmission electron microscope and an ultraviolet spectrophotometer, respectively. Cell proliferation was analyzed by MTT assay. Proteins were analyzed by Western blot. IL-12 and HMGB1 levels were estimated by ELISA kits. Live/dead staining assay was performed using a Calcein-AM/PI kit. ATP production was detected using an ATP assay kit. The xenografts in vivo were estimated in C57BL/6 mice. The levels of CD80+/CD86+, CD3+/CD4+ and CD3+/CD8+ were analyzed by flow cytometry. Results: CPP could effectively express EGFP or IL-12 and increase ROS levels. Laser treatment promoted CPP-IL-12 induced the number of dead or apoptotic cell. CPP-IL-12 and laser could further enhance CALR levels and extracellular HMGB1 levels and decrease intracellular HMGB1 and ATP levels, indicating that it may induce immunogenic cell death (ICD). The tumors and weights of xenografts in CPP-IL-12 or laser-treated mice were significantly reduced than in controls. The IL-12 expression, the CD80+/CD86+ expression of DC from lymph glands, and the number of CD3+/CD8+T or CD3+/CD4+T cells from the spleen increased in CPP-IL-12-treated or laser-treated xenografts compared with controls. The levels of granzyme B, IFN-γ, and TNF-α in the serum of CPP-IL-12-treated mice increased. Interestingly, CPP-IL-12 treatment in local xenografts in the back of mice could effectively inhibit the growth of the distant untreated tumor. Conclusion: The novel CPP-IL-12 could overexpress IL-12 in melanoma cells and achieve immunotherapy to melanoma through inducing ICD, activating CD4+ T cell, and enhancing the function of tumor-reactive CD8+ T cells.


Assuntos
Proteína HMGB1 , Melanoma , Humanos , Camundongos , Animais , Interleucina-12 , Linfócitos T CD8-Positivos , Melanoma/terapia , Melanoma/metabolismo , Proteína HMGB1/metabolismo , Morte Celular Imunogênica , Camundongos Endogâmicos C57BL , Proliferação de Células , Linfócitos T CD4-Positivos , Trifosfato de Adenosina/metabolismo
2.
Nat Commun ; 15(1): 2677, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538591

RESUMO

α-Synuclein forms amyloid fibrils that are critical in the progression of Parkinson's disease and serves as the pathological hallmark of this condition. Different posttranslational modifications have been identified at multiple sites of α-synuclein, influencing its conformation, aggregation and function. Here, we investigate how disease-related phosphorylation and O-GlcNAcylation at the same α-synuclein site (S87) affect fibril structure and neuropathology. Using semi-synthesis, we obtained homogenous α-synuclein monomer with site-specific phosphorylation (pS87) and O-GlcNAcylation (gS87) at S87, respectively. Cryo-EM revealed that pS87 and gS87 α-synuclein form two distinct fibril structures. The GlcNAc situated at S87 establishes interactions with K80 and E61, inducing a unique iron-like fold with the GlcNAc molecule on the iron handle. Phosphorylation at the same site prevents a lengthy C-terminal region including residues 73 to 140 from incorporating into the fibril core due to electrostatic repulsion. Instead, the N-terminal half of the fibril (1-72) takes on an arch-like fibril structure. We further show that both pS87 and gS87 α-synuclein fibrils display reduced neurotoxicity and propagation activity compared with unmodified α-synuclein fibrils. Our findings demonstrate that different posttranslational modifications at the same site can produce distinct fibril structures, which emphasizes link between posttranslational modifications and amyloid fibril formation and pathology.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Humanos , alfa-Sinucleína/metabolismo , Fosforilação , Doença de Parkinson/patologia , Processamento de Proteína Pós-Traducional , Amiloide/metabolismo , Ferro
3.
Commun Biol ; 7(1): 215, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383737

RESUMO

Blocking immune checkpoint CD47/SIRPα is a useful strategy to engineer macrophages for cancer immunotherapy. However, the roles of CD47-related noncoding RNA in regulating macrophage phagocytosis for lung cancer therapy remain unclear. This study aims to investigate the effects of long noncoding RNA (lncRNA) on the phagocytosis of macrophage via CD47 and the proliferation of non-small cell lung cancer (NSCLC) via TIPRL. Our results demonstrate that lncRNA KCTD21-AS1 increases in NSCLC tissues and is associated with poor survival of patients. KCTD21-AS1 and its m6A modification by Mettl14 promote NSCLC cell proliferation. miR-519d-5p gain suppresses the proliferation and metastasis of NSCLC cells by regulating CD47 and TIPRL. Through ceRNA with miR-519d-5p, KCTD21-AS1 regulates the expression of CD47 and TIPRL, which further regulates macrophage phagocytosis and cancer cell autophagy. Low miR-519d-5p in patients with NSCLC corresponds with poor survival. High TIPRL or CD47 levels in patients with NSCLC corresponds with poor survival. In conclusion, we demonstrate that KCTD21-AS1 and its m6A modification promote NSCLC cell proliferation, whereas miR-519d-5p inhibits this process by regulating CD47 and TIPRL expression, which further affects macrophage phagocytosis and cell autophagy. This study provides a strategy through miR-519-5p gain or KCTD21-AS1 depletion for NSCLC therapy by regulating CD47 and TIPRL.


Assuntos
Adenina , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Humanos , Adenina/análogos & derivados , Autofagia/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Antígeno CD47/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Peptídeos e Proteínas de Sinalização Intracelular , Neoplasias Pulmonares/patologia , Macrófagos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Fagocitose , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
4.
Adv Mater ; 36(16): e2308155, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38295870

RESUMO

Following the success of the dendritic cell (DC) vaccine, the cell-based tumor vaccine shows its promise as a vaccination strategy. Except for DC cells, targeting other immune cells, especially myeloid cells, is expected to address currently unmet clinical needs (e.g., tumor types, safety issues such as cytokine storms, and therapeutic benefits). Here, it is shown that an in situ injected macroporous myeloid cell adoptive scaffold (MAS) not only actively delivers antigens (Ags) that are triggered by scaffold-infiltrating cell surface thiol groups but also releases granulocyte-macrophage colony-stimulating factor and other adjuvant combos. Consequently, this promotes cell differentiation, activation, and migration from the produced monocyte and DC vaccines (MASVax) to stimulate antitumor T-cell immunity. Neoantigen-based MASVax combined with immune checkpoint blockade induces rejection of established tumors and long-term immune protection. The combined depletion of immunosuppressive myeloid cells further enhances the efficacy of MASVax, indicating the potential of myeloid cell-based therapies for immune enhancement and normalization treatment of cancer.


Assuntos
Vacinas Anticâncer , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Vacinação , Engenharia Celular , Células Mieloides , Células Dendríticas
5.
J Biol Chem ; 300(3): 105667, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272228

RESUMO

The aggregation of α-Synuclein (α-Syn) into amyloid fibrils is the hallmark of Parkinson's disease. Under stress or other pathological conditions, the accumulation of α-Syn oligomers is the main contributor to the cytotoxicity. A potential approach for treating Parkinson's disease involves preventing the accumulation of these α-Syn oligomers. In this study, we present a novel mechanism involving a conserved group of disorderly proteins known as small EDRK-rich factor (SERF), which promotes the aggregation of α-Syn through a cophase separation process. Using diverse methods like confocal microscopy, fluorescence recovery after photobleaching assays, solution-state NMR spectroscopy, and Western blot, we determined that the N-terminal domain of SERF1a plays a role in the interactions that occur during cophase separation. Within these droplets, α-Syn undergoes a gradual transformation from solid condensates to amyloid fibrils, while SERF1a is excluded from the condensates and dissolves into the solution. Notably, in vivo experiments show that SERF1a cophase separation with α-Syn significantly reduces the deposition of α-Syn oligomers and decreases its cellular toxicity under stress. These findings suggest that SERF1a accelerates the conversion of α-Syn from highly toxic oligomers to less toxic fibrils through cophase separation, thereby mitigating the biological damage of α-Syn aggregation.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Humanos , alfa-Sinucleína/química , alfa-Sinucleína/metabolismo , Amiloide/química , Doença de Parkinson/metabolismo , Separação de Fases , Agregados Proteicos , Agregação Patológica de Proteínas/metabolismo , Fatores de Transcrição , Antígenos de Grupos Sanguíneos/química , Antígenos de Grupos Sanguíneos/metabolismo , Células HeLa , Eletricidade Estática
6.
Rev Esp Enferm Dig ; 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38235649

RESUMO

A 65-year-old woman was diagnosed with an exogenous submucosal tumor located in the fornix of the stomach, on the basis of the endoscopic ultrasound and enhanced CT findings. She refused surgery and referred for EFTR. It is difficult to perform EFTR at the gastric fornix and suture the large surgical defect. Therefore, we created technique of triangular pulley traction combined with pre-closure.

7.
Biomed Pharmacother ; 170: 115936, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38039755

RESUMO

Isogarcinol (ISO), a cytotoxic polycyclic polyprenylated acylphloroglucinol isolated from the edible fruits of Garcinia multiflora. However, synergistic combination of ISO and dexamethasone (DEX) to overcome leukemia glucocorticoid resistance has never been investigated. Therefore, in this study, the effects of ISO in combination with DEX was conducted on leukemia in vivo and glucocorticoid resistance in vitro. As a result, the combination of the two compounds could efficiently inhibit leukemia progression in mice and reverse DEX resistance in acute lymphoblastic leukemia (ALL) Jurkat cells. Significantly, our findings indicated that c-Myc may be a potential target of ISO, as it is involved in cell cycle arrest and apoptosis by the combination of ISO and DEX in Jurkat cells. Furthermore, western blot analysis revealed that ISO and DEX inhibits the PI3K/Akt/mTOR signaling pathway and promotes the nuclear translocation of glucocorticoid receptor (GR), which activates target genes NR3C1 and TSC22D3, leading to apoptosis in Jurkat cells. Hence, our results suggest that ISO, as a safe and effective food-derived agent, can enhance the anti-leukemia effects of DEX.


Assuntos
Garcinia , Leucemia-Linfoma Linfoblástico de Células Precursoras , Animais , Camundongos , Glucocorticoides/farmacologia , Receptores de Glucocorticoides/metabolismo , Dexametasona/farmacologia , Frutas , Fosfatidilinositol 3-Quinases , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Apoptose
8.
ACS Appl Mater Interfaces ; 15(51): 59165-59174, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38100370

RESUMO

Immunotherapy is known to be a promising strategy in the clinical treatment of malignant tumors, but it has received generally low response rates in various tumors because of the poor immunogenicity and multiple immunosuppressive microenvironments. A self-delivery photodynamic re-educator, denoted as CCXB, is synthesized through the self-assembly of chlorine e6 (Ce6) and celecoxib (CXB). As a carrier-free nanomedicine, CCXB shows a high drug loading rate, improved water stability, superior cellular uptake, and tumor accumulation capability. In comparison with free Ce6, CCXB triggers much stronger photodynamic therapy (PDT) to reduce the proliferation of breast cancer cells and activates robust immune responses via the induction of immunogenic cell death (ICD). Better yet, CXB-mediated cyclooxygenase 2 (COX-2) inhibition can decrease the level of synthesis of prostaglandin E2 (PGE2) to further improve immunosuppressive microenvironments. With the increase of cytotoxic T lymphocytes (CTLs) and decrease of regulatory T cells (Tregs) in tumor, in vivo antitumor immunity is significantly amplified to inhibit the metastasis of breast cancer. This study sheds light on developing drug codelivery systems with collaborative mechanisms for immunotherapy of metastatic tumors.


Assuntos
Neoplasias da Mama , Nanopartículas , Fotoquimioterapia , Humanos , Feminino , Morte Celular Imunogênica , Neoplasias da Mama/patologia , Imunoterapia , Linfócitos T Citotóxicos , Imunossupressores/farmacologia , Linhagem Celular Tumoral , Fármacos Fotossensibilizantes/farmacologia , Microambiente Tumoral
9.
Gynecol Endocrinol ; 39(1): 2276167, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37931646

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) was known as the common endocrine disease in women, featured as hyperandrogenism, ovulation disorders, etc. Fat mass and obesity-associated protein (FTO), a m6A demethylase, is abnormal in the occurrence of ovarian diseases. However, the mechanism of FTO in the pathogenesis of PCOS is still unclear. METHODS: The level of FTO in clinical samples, PCOS rat with hyperandrogenism and granulosa cells (GCs) lines effected by DHT were investigated by ELISA, qRT-PCR, WB, and IHC, while m6A RNA methylation level was studied by m6A Colorimetric and androgen level was tested through ELISA. Changes in steroid hormone synthetase and androgen receptor (AR)/prostate-specific antigen (PSA) levels in vitro were visualized by WB after transient transfection silenced FTO. The effect of DHT combined with FTO inhibitor meclofenamic acid (MA) on FTO, AR/PSA, and AKT phosphorylation were also demonstrated by WB. The co-localization of FTO and AR in KGN cells was analyzed by confocal microscopy, and the physiological interaction between FTO and AR was studied by Co-IP assay. The effect of FTO-specific inhibitor MA, AKT phosphorylation inhibitor LY294002, and the combined them on GCs proliferation and cell cycle were evaluated by drug combination index, EDU assay, and flow cytometry analysis. RESULTS: FTO expression was upregulated in follicular fluid and GCs in PCOS patients clinically. The high FTO expression in patients was negative with the level of m6A, but positive with the level of androgen. The upregulation of FTO was accompanied with a decrease in the level of m6A in PCOS rat with hyperandrogenism. Dihydrotestosterone (DHT) promoted the FTO expression and inhibited m6A content as a dose-dependent way in vitro. In contrast, suppression of FTO with siRNA attenuated the expression of steroid hormone synthetase such as CYP11A1, CYP17A1, HSD11B1, HSD3B2 except CYP19A1 synthetase, ultimately inducing the decrease of androgen level. Suppression of FTO also decreased the biological activity of androgen through downregulation AR/PSA. MA treatment as the specific FTO antagonist decreased cell survival in time- and dose-dependent way in GCs lines. Correspondingly, MA treatment decreased the expression of FTO, AR/PSA expression, and AKT phosphorylation in the presence of DHT stimulation. Additionally, we also speculate there is a potential relation between FTO and AR according to FTO was co-localized and interacted with AR in KGN cells. Compared with AKT phosphorylation inhibitor LY294002 or MA alone, LY294002 combined with MA synergistically inhibited cell survival and increased G2/M phase arrest in GC line. CONCLUSIONS: We first evaluated the correlation of FTO and m6A in PCOS clinically, and further explored the mechanism between FTO and hyperandrogenism in PCOS animal and cell models. These findings contributed the potential therapy by targeting the FTO for hyperandrogenism in PCOS.


Assuntos
Hiperandrogenismo , Síndrome do Ovário Policístico , Animais , Feminino , Humanos , Ratos , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Androgênios/metabolismo , Di-Hidrotestosterona/metabolismo , Células da Granulosa/metabolismo , Hiperandrogenismo/complicações , Ligases/metabolismo , Síndrome do Ovário Policístico/complicações , Antígeno Prostático Específico/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
10.
J Med Chem ; 66(18): 13266-13279, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37676021

RESUMO

Protein or peptide cancer vaccines usually include immune potentiators, so-called adjuvants. However, it remains challenging to identify structurally simple, chemically accessible synthetic molecules that are effective and safe as vaccine adjuvant. Here, we present cholicamideß (6), a self-assembling small-molecule vaccine adjuvant with an improved toxicity profile and proven efficacy in vivo. We demonstrate that cholicamideß (6), which is less cytotoxic than its parent compound, forms virus-like particles to potently activate dendritic cells with the concomitant secretion of cytokines. When combined with a peptide antigen, cholicamideß (6) potentiated the antigen presentation on dendritic cells to induce antigen-specific T cells. As a therapeutic cancer vaccine adjuvant in mice, a mixture of cholicamideß (6) and a peptide antigen protected mice from the challenges of malignant cancer cells without overt toxicity. Cholicamideß (6) may offer a translational opportunity as an unprecedented class of small-molecule cancer vaccine adjuvants.


Assuntos
Vacinas Anticâncer , Neoplasias , Animais , Camundongos , Vacinas Anticâncer/uso terapêutico , Adjuvantes de Vacinas , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/química , Linfócitos T , Adjuvantes Farmacêuticos , Vacinas de Subunidades Antigênicas , Peptídeos , Células Dendríticas
12.
ACS Appl Bio Mater ; 6(7): 2816-2825, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37326439

RESUMO

Inflammation activation is accompanied by tumor growth, migration, and differentiation. Photodynamic therapy (PDT) can trigger an inflammatory response to cause negative feedback of tumor inhibition. In this paper, a feedback-elevated antitumor amplifier is developed by constructing self-delivery nanomedicine for PDT and cascade anti-inflammation therapy. Based on the photosensitizer chlorin e6 (Ce6) and COX-2 inhibitor indomethacin (Indo), the nanomedicine is prepared via molecular self-assembly technology without additional drug carriers. It is exciting that the optimized nanomedicine (designated as CeIndo) possesses favorable stability and dispersibility in the aqueous phase. Moreover, the drug delivery efficiency of CeIndo is significantly improved, which could be effectively accumulated at the tumor site and internalized by tumor cells. Importantly, CeIndo not only exhibits a robust PDT efficacy on tumor cells but also drastically decreases the PDT-induced inflammatory response in vivo, resulting in feedback-elevated tumor inhibition. By virtue of the synergistic effect of PDT and cascade inflammation suppression, CeIndo tremendously reduces tumor growth and leads to a low side effect. This study presents a paradigm for the development of codelivery nanomedicine for enhanced tumor therapy through inflammation suppression.


Assuntos
Fotoquimioterapia , Humanos , Fotoquimioterapia/efeitos adversos , Fotoquimioterapia/métodos , Nanomedicina , Retroalimentação , Linhagem Celular Tumoral , Fármacos Fotossensibilizantes/farmacologia , Inflamação/tratamento farmacológico
13.
Zhen Ci Yan Jiu ; 48(5): 515-8, 2023 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-37247867

RESUMO

Acupoint Dubi(ST35), one of the commonly used acupuncture points in clinical practice, has long been equated as the acupoint Waixiyan(EX-LE5) in the academic community. By referring to the location of ST35 elaborated in the relevant literature in the ancient and modern times, we analyze the evolution of its position and expound its clinical significance of the correct positioning in the present paper. We think that under posture of knee flexion, the position of ST35 should be between the lower edge of the patella and the upper tip of the tibia, at the midpoint of the patella ligament.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Relevância Clínica , Tíbia
14.
Front Psychol ; 14: 1093875, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37020914

RESUMO

Background: Understanding the compliance of infected individuals and the psychological process underlying compliance during pandemics is important for preventing and controlling the spread of pathogens. Our study investigated whether fundamental social motives mediate the relationship between having infectious disease and compliance. Methods: An online survey was conducted in March 2020, during the severe phase of the COVID-19 outbreak in China to collect data from 15,758 participants. The survey comprised self-report questionnaires with items pertaining to current symptoms (COVID-19 symptoms, other symptoms or no symptoms), the Fundamental Social Motive Inventory, and measures of compliance. Correlation analysis, linear regression analysis, and structural equation model were used for data analysis. Results: The participants with COVID-19 symptoms had lower levels of compliance than those without symptoms, and their lower compliance was caused by a decrease in disease avoidance (indirect effect = -0.058, 95% CI = [-0.061, -0.056]) and familial motives (indirect effect = -0.113, 95% CI = [-0.116, -0.062]). Whereas exclusion concern (indirect effect = 0.014, 95% CI = [0.011, 0.017]) suppressed the effects of COVID-19 symptoms on compliance, the effect disappeared in the multiple mediation model, while those of disease avoidance and familial motives remained. Conclusion: Our findings emphasize the critical role of disease avoidance and familial motives in promoting compliance with public health norms during pandemics and suggest that enhancing these motives may serve as an effective intervention strategy to mitigate noncompliance among potentially infected individuals.

15.
World J Clin Cases ; 11(6): 1426-1433, 2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36926119

RESUMO

BACKGROUND: Primary malignant melanoma of the esophagus (PMME) is a rare malignant disease whose clinical and molecular pathological features, origin and pathogenesis, diagnosis and treatment have not been elucidated. CASE SUMMARY: In this paper, we report a case of a 73-year-old male with PMME. The patient complained of progressive dysphagia accompanied by substantial weight loss. Gastroscopy revealed a purple black bulging-type mass in the lower esophagus with easy bleeding on contact and scattered satellite lesions in the stomach. Histopathological biopsy revealed melanocytes in the esophageal mucosa. Physical examination and multidisciplinary consultation led to diagnostic exclusion of melanoma originating in other organs, such as the skin. Through this case report and literature review, we aimed to describe the clinical and molecular pathological features of PMME and summarize possible pathways of pathogenesis as well as cutting-edge therapeutic advances. CONCLUSION: PMME is a rare malignancy of the esophagus with a poor prognosis. Clinicians should raise their awareness and be able to identify early lesions.

16.
ACS Chem Neurosci ; 14(7): 1220-1225, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36939323

RESUMO

Tau plays a major role in Alzheimer's disease (AD) and several other neurodegenerative diseases. Tau undergoing liquid-liquid phase separation (LLPS) performs specific physiological functions, induces pathological processes, and contributes to neurodegeneration. Regulating Tau phase separation helps maintain physiological functions of Tau and inhibits pathological aggregation. Here, we show that the 14-3-3 zeta isoform (14-3-3ζ) participates in Tau LLPS. 14-3-3ζ can undergo co-phase separation with WT Tau, participate in and stabilize Tau droplets, and inhibit Tau droplet-driven tubulin assembly. On the other hand, 14-3-3ζ disrupts the LLPS of phosphorylated and glycated Tau, thereby inhibiting the amyloid aggregation initiated by LLPS.


Assuntos
Doença de Alzheimer , Proteínas tau , Humanos , Proteínas tau/metabolismo , Proteínas 14-3-3/metabolismo , Doença de Alzheimer/patologia , Isoformas de Proteínas
17.
Adv Mater ; 35(14): e2211009, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36660910

RESUMO

The development of photochemical self-healing polymers faces the the following bottlenecks: i) only the surface cracks can be restored and ii) materials' mechanical properties are lower. To break these bottlenecks, cross-linked poly(urethane-dithiocarbamate)s carrying photo-reversible dithiocarbamate bonds covalently linked to indole chromophores and benzyl groups are designed. The conjugated structure of the chromophore and benzyl enhances the addition reactivity of thiocarbonyl moiety and facilitates photo-cleavage of CS bond, so that transfer of the created radicals among dithiocarbamate linkages is promoted. Accordingly, reshuffling of the reversibly cross-linked networks via dynamic exchange between the activated dithiocarbamates is enabled in both surface layer and the interior upon exposure to the low-intensity ultraviolet (UV) light from the sun. It is found that the damages up to a centimeter below the surface can be effectively recovered in the sunshine, which greatly exceeds the maximum penetration distance of UV light (hundreds of microns). Besides, tensile strength and failure strain of the poly(urethane-dithiocarbamate) are superior to the reported photo-reversible polymers, achieving the record-high 33.8 MPa and 782.0% owing to the wide selectivity of soft/hard blocks, multiple interactions, and appropriate cross-linking architecture. The present work provides a novel paradigm of photo self-healing polymers capable of re-bonding cracks even out of the reach of the illumination.

18.
J Pept Sci ; 29(3): e3454, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36181422

RESUMO

Considering the fact that site-selective late-stage diversification of peptides and proteins remains a challenge for biochemistry, strategies targeting low-abundance natural amino acids need to be further developed. As an extremely oxidation-sensitive and low-abundance amino acid, methionine emerges as a promising target for chemo- and site-selective modification. Herein we report an efficient and highly selective modification on methionine residues by one-pot O- and N-transfer reaction, generating sulfoximine-modified peptides with near-perfect conversion within 10 min. Moreover, the great tolerance to other natural amino acids has been demonstrated in reactions with various peptide substrates. To demonstrate the generality of this protocol, we have modified natural peptides and obtained sulfoximination products with high conversion rates. This methodology provides a novel strategy as the expansion of the methionine-based peptide functionalization toolbox.


Assuntos
Metionina , Proteínas , Metionina/química , Metionina/metabolismo , Proteínas/química , Peptídeos/química , Racemetionina/metabolismo , Estresse Oxidativo
19.
Biomater Sci ; 11(1): 162-169, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36398488

RESUMO

Tumor cells activate DNA repair pathways to combat the oxidative damage induced by reactive oxygen species (ROS), contributing to their resistance to photodynamic therapy (PDT). Herein, a self-delivery photodynamic sensitizer is developed to enhance oxidative damage by blocking the DNA repair pathway through poly(ADP-ribose) polymerase (PARP) inhibition. Specifically, the photodynamic sensitizer (CeOla) is constructed based on the self-assembly of the photosensitizer chlorine e6 (Ce6) and the PARP inhibitor olaparib (Ola). Of note is that carrier free CeOla has a high drug content and favorable water stability, which could be effectively internalized by tumor cells for robust PDT upon light irradiation. Moreover, CeOla could inhibit the activation of PARP, promote the upregulation of γ-H2AX and reduce the expression of Rad51, thereby blocking the DNA repair pathway to sensitize tumor cells for PDT. As a consequence, the self-delivery CeOla greatly promotes the tumor cell apoptosis and shows a high antitumor performance with low side effects. It serves as a novel platform for the development of self-delivery nanomedicine to overcome oxidative resistance in tumor treatment.


Assuntos
Antineoplásicos , Fotoquimioterapia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Antineoplásicos/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Dano ao DNA , Poli(ADP-Ribose) Polimerases/metabolismo , Linhagem Celular Tumoral
20.
Front Oncol ; 12: 1032850, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387210

RESUMO

Long non-coding RNAs (lncRNAs) modulate cell proliferation, cycle, and apoptosis. However, the role of lncRNA-WFDC21P in the tumorigenesis of triple-negative breast cancer (TNBC) remains unclear. Results of this study demonstrated that WFDC21P levels significantly increased in TNBC, which was associated with the poor survival of patients. WFDC21P overexpression significantly promoted TNBC cell proliferation and metastasis. WFDC21P interacted with miR-628-5p, which further suppressed cell proliferation and metastasis by negatively regulating Smad3-related gene expression. Recovery of miR-628-5p weakened the roles of WFDC21P in promoting the growth and metastasis of TNBC cells. Moreover,N6-methyladenosine (m6A) modification upregulated WFDC21P expression in the TNBC cells. WFDC21P and its m6A levels were increased after methyltransferase like 3 (METTL3) overexpression but reduced after METTL3 silencing. The proliferation and metastasis of TNBC cells were promoted by METTL3 overexpression but suppressed by METTL3 silencing. This study demonstrated the vital roles of WFDC21P and its m6A in regulating the proliferation and metastasis of TNBC cells via the WFDC21P/miR-628/SMAD3 axis.

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