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1.
Nat Commun ; 15(1): 3669, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38693119

RESUMO

Oncolytic viruses (OVs) show promise as a cancer treatment by selectively replicating in tumor cells and promoting antitumor immunity. However, the current immunogenicity induced by OVs for tumor treatment is relatively weak, necessitating a thorough investigation of the mechanisms underlying its induction of antitumor immunity. Here, we show that HSV-1-based OVs (oHSVs) trigger ZBP1-mediated PANoptosis (a unique innate immune inflammatory cell death modality), resulting in augmented antitumor immune effects. Mechanistically, oHSV enhances the expression of interferon-stimulated genes, leading to the accumulation of endogenous Z-RNA and subsequent activation of ZBP1. To further enhance the antitumor potential of oHSV, we conduct a screening and identify Fusobacterium nucleatum outer membrane vesicle (Fn-OMV) that can increase the expression of PANoptosis execution proteins. The combination of Fn-OMV and oHSV demonstrates potent antitumor immunogenicity. Taken together, our study provides a deeper understanding of oHSV-induced antitumor immunity, and demonstrates a promising strategy that combines oHSV with Fn-OMV.


Assuntos
Fusobacterium nucleatum , Herpesvirus Humano 1 , Terapia Viral Oncolítica , Vírus Oncolíticos , Proteínas de Ligação a RNA , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 1/genética , Vírus Oncolíticos/genética , Vírus Oncolíticos/imunologia , Animais , Humanos , Terapia Viral Oncolítica/métodos , Camundongos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/imunologia , Linhagem Celular Tumoral , Fusobacterium nucleatum/imunologia , Neoplasias/terapia , Neoplasias/imunologia , Feminino , Imunidade Inata , Camundongos Endogâmicos BALB C
2.
Nat Commun ; 15(1): 3254, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627395

RESUMO

The past century has witnessed a large number of reports on the Z/E isomerization of alkenes. However, the vast majority of them are still limited to the isomerization of di- and tri-substituted alkenes. The stereospecific Z/E isomerization of tetrasubstituted alkenes remains to be an underdeveloped area, thus lacking in a stereodivergent synthesis of axially chiral alkenes. Herein we report the atroposelective synthesis of tetrasubstituted alkene analogues by asymmetric allylic substitution-isomerization, followed by their Z/E isomerization via triplet energy transfer photocatalysis. In this regard, the stereodivergent synthesis of axially chiral N-vinylquinolinones is achieved efficiently. Mechanistic studies indicate that the benzylic radical generation and distribution are two key factors for preserving the enantioselectivities of axially chiral compounds.

3.
ACS Chem Biol ; 19(5): 1040-1044, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38620022

RESUMO

Cysteine conjugation is widely used to constrain phage displayed peptides for the selection of cyclic peptides against specific targets. In this study, the nontoxic Bi3+ ion was used as a cysteine conjugation reagent to cross-link peptide libraries without compromising phage infectivity. We constructed a randomized 3-cysteine peptide library and cyclized it with Bi3+, followed by a selection against the maltose-binding protein as a model target. Next-generation sequencing of selection samples revealed the enrichment of peptides containing clear consensus sequences. Chemically synthesized linear and Bi3+ cyclized peptides were used for affinity validation. The cyclized peptide showed a hundred-fold better affinity (0.31 ± 0.04 µM) than the linear form (39 ± 6 µM). Overall, our study proved the feasibility of developing Bi3+ constrained bicyclic peptides against a specific target using phage display, which would potentially accelerate the development of new peptide-bismuth bicycles for therapeutic or diagnostic applications.


Assuntos
Biblioteca de Peptídeos , Peptídeos Cíclicos , Peptídeos Cíclicos/química , Cisteína/química , Proteínas Ligantes de Maltose/metabolismo , Proteínas Ligantes de Maltose/química , Proteínas Ligantes de Maltose/genética , Ciclização , Peptídeos/química , Sequência de Aminoácidos
4.
Am J Cancer Res ; 13(10): 4888-4902, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37970340

RESUMO

Based on its absence in normal tissues and its role in tumorigenesis and tumor progression, insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3), a reader of N6-methyladenosine (M6A) on RNA, represents a putative valuable and specific target for some cancer therapy. In this study, we performed bioinformatic analysis and immunohistochemistry (IHC) to find that IGF2BP3 was highly expressed in tumor epithelial cells and fibroblasts of ovarian cancer (OC), and was associated with poor prognosis, metastasis, and chemosensitivity in OC patients. In particular, we discovered that knockdown IGF2BP3 expression inhibited the malignant phenotype of OC cell lines by decreasing the protein levels of c-MYC, VEGF, CDK2, CDK6, and STAT1. To explore the feasibility of IGF2BP3 as a therapeutic target for OC, a small molecular AE-848 was designed and screened by molecular operating environment (MOE), which not only could duplicate the above results of knockdown assay but also reduced the expression of c-MYC in M2 macrophages and tumor-associated macrophages and promoted the cytokine IFN-γ and TNF-α secretion. The pharmacodynamic models of two kinds of OC bearing animals were suggested that systemic therapy with AE-848 significantly inhibited tumor growth by reducing the expression of tumor-associated antigen (c-MYC/VEGF/Ki67/CDK2) and improving the anti-tumor effect of macrophages. These results suggest that AE-848 can inhibit the growth and progression of OC cells by disrupting the stability of the targeted mRNAs of IGF2BP3 and may be a targeted drug for OC treatment.

5.
Antioxidants (Basel) ; 12(9)2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37759980

RESUMO

As the organ with the largest contact area with the outside world, the intestine is home to a large number of microorganisms and carries out the main functions of food digestion, absorption, and metabolism. Therefore, there is a very active metabolism of substances and energy in the gut, which is easily attacked by oxygen free radicals. What is more, oxidative stress can gradually and slowly cause very serious damage to the gut. Hence, maintaining redox balance is essential for maintaining environmental balance in the gut. Our previous studies have demonstrated that the extract of Sonchus brachyotus DC. (SBE) has been shown to be capable of repairing oxidative damage, while it has not been demonstrated that it can prevent oxidative stress or how it develops. In this work, we investigated the prevention of oxidative stress and its mechanism in SBE based on the H2O2-induced oxidative damage model in Caco-2 cells; the results indicate that SBE can reduce the contents of ROS and MDA and increase the activities of SOD and CAT in preventing oxidative stress. Then, at the mRNA and protein level, SBE can up-regulate and down-regulate the expression of related genes (NFE2L2, KEAP1, HMOX1, NQO1, SOD1, CAT, and GPX1) and proteins involved in the Nrf2-Keap1-ARE signaling pathway. In conclusion, SBE plays a preventive role in oxidative stress through the Nrf2-Keap1-ARE signaling pathway.

6.
BMC Infect Dis ; 23(1): 590, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37697258

RESUMO

BACKGROUND: Vitamin B6 is an essential water-soluble vitamin for humans. It is often used to prevent a variety of neuropathies, relieve vomiting, and relieve symptoms such as hand and foot neuritis. AIM: To evaluate whether vitamin B6 can alleviate the adverse reactions caused by the quadruple anti-Helicobacter pylori treatment regimen containing minocycline and metronidazole. METHODS: In this randomized controlled trial, 280 patients with H. pylori infection were randomly placed into one of two treatment groups-the conventional treatment group and the vitamin B6 supplement treatment group-for 2 weeks. The primary endpoint was the total incidence of adverse reactions up to 2 weeks after treatment initiation. The study was designed according to CONSORT Medicinal Interventions. And it was registered with Chinese Clinical Trial Registry under the number ChiCTR2100053833. RESULTS: In terms of efficacy, vitamin B6 does not affect the efficacy of conventional regimen. In the vitamin B6 supplement treatment group, the incidence of adverse reactions was 56.92%, which was significantly lower than the 74.62% observed in the conventional treatment group. In addition, the severity of adverse reactions was also significantly reduced. The proportion of moderate to severe central nervous system symptoms decreased from 58.7 to 14.63%. And, the proportion of moderate to severe gastrointestinal reactions decreased from 33.33 to 0%. We speculate that the mechanism of vitamin B6 of reducing adverse reaction may be related to the production of GABA in the brain. CONCLUSIONS: Vitamin B6 can alleviate adverse reactions of the quadruple anti-H. pylori regimen containing minocycline and metronidazole.


Assuntos
Helicobacter pylori , Vitamina B 6 , Humanos , Vitamina B 6/uso terapêutico , Metronidazol/efeitos adversos , Minociclina , Protocolos Clínicos , Vitaminas
7.
J Am Chem Soc ; 145(32): 17689-17699, 2023 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-37550880

RESUMO

Covalent organic frameworks (COFs) have emerged as a promising class of crystalline porous materials for cancer phototherapy, due to their exceptional characteristics, including light absorption, biocompatibility, and photostability. However, the aggregation-caused quenching effect and apoptosis resistance often limit their therapeutic efficacy. Herein, we demonstrated for the first time that linking luminogens with aggregation-induced emission effect (AIEgens) into COF networks via vinyl linkages was an effective strategy to construct nonmetallic pyroptosis inducers for boosting antitumor immunity. Mechanistic investigations revealed that the formation of the vinyl linkage in the AIE COF endowed it with not only high brightness but also strong light absorption ability, long lifetime, and high quantum yield to favor the generation of reactive oxygen species for eliciting pyroptosis. In addition, the synergized system of the AIE COF and αPD-1 not only effectively eradicated primary and distant tumors but also inhibited tumor recurrence and metastasis in a bilateral 4T1 tumor model.


Assuntos
Estruturas Metalorgânicas , Fotoquimioterapia , Piroptose , Apoptose , Carbono , Cloreto de Polivinila
8.
Cancer Lett ; 568: 216293, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37392991

RESUMO

Tertiary lymphoid structures (TLSs) are organized aggregates of lymphocytes and antigen-presenting cells that develop in non-lymphoid tissues during chronic inflammation, resembling the structure and features of secondary lymphoid organs. Numerous studies have shown that TLSs may be an important source of antitumor immunity within solid tumors, facilitating T cell and B cell differentiation and the subsequent production of antitumor antibodies, which are beneficial for cancer prognosis and responses to immunotherapy. The formation of TLSs relies on the cytokine signaling network between heterogeneous cell populations, such as stromal cells, lymphocytes and cancer cells. The coordinated action of various cytokines drives the complex process of TLSs development. In this review, we will comprehensively describe the mechanisms by which various cytokines regulate TLS formation and function, and the recent advancements and therapeutic potential of exploiting these mechanisms to induce intratumoral TLSs as an emerging immunotherapeutic approach or to enhance existing immunotherapy.


Assuntos
Neoplasias , Estruturas Linfoides Terciárias , Humanos , Citocinas , Estruturas Linfoides Terciárias/patologia , Neoplasias/patologia , Imunoterapia , Anticorpos , Prognóstico , Microambiente Tumoral
9.
Head Neck ; 45(9): 2161-2172, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37466293

RESUMO

BACKGROUND: Cysteine-rich protein 2 (CSRP2) is discovered as oncogene. The study aims to investigate the clinical significance and potential mechanism of CSRP2 in head and neck squamous cell carcinoma (HNSCC). METHODS: CSRP2 expression was explored by immunohistochemistry tissue microarrays and Western blotting in HNSCC. The effect of CSRP2 on the cancer stemness and epithelial-to-mesenchymal transition (EMT) of HNSCC cells was investigated by sphere formation, wound healing, and transwell assays. The vitro and vivo experiments revealed that CSRP2 modulated cancer stemness and EMT phenotypes in HNSCC. RESULTS: CSRP2 was overexpressed in HNSCC patients and presented poor prognosis. CSRP2 knockdown inhibited the migration and invasion ability of the HNSCC cells. And CSRP2 expression was closely associated with CSCs markers, EMT-transcription factor, new oncoprotein, and immune checkpoint. CONCLUSION: The overexpression of CSRP2 indicates poor prognosis and plays a key role in maintaining the cancer cell stemness and EMT.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/genética , Fatores de Transcrição/genética , Fenótipo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Movimento Celular , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Proteínas Musculares/farmacologia , Proteínas Nucleares/genética , Proteínas com Domínio LIM/genética
10.
Mol Ther ; 31(7): 2154-2168, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-36869589

RESUMO

Immune checkpoint blockade (ICB) treatment has demonstrated excellent medical effects in oncology, and it is one of the most sought after immunotherapies for tumors. However, there are several issues with ICB therapy, including low response rates and a lack of effective efficacy predictors. Gasdermin-mediated pyroptosis is a typical inflammatory death mode. We discovered that increased expression of gasdermin protein was linked to a favorable tumor immune microenvironment and prognosis in head and neck squamous cell carcinoma (HNSCC). We used the mouse HNSCC cell lines 4MOSC1 (responsive to CTLA-4 blockade) and 4MOSC2 (resistant to CTLA-4 blockade) orthotopic models and demonstrated that CTLA-4 blockade treatment induced gasdermin-mediated pyroptosis of tumor cells, and gasdermin expression positively correlated to the effectiveness of CTLA-4 blockade treatment. We found that CTLA-4 blockade activated CD8+ T cells and increased the levels of interferon γ (IFN-γ) and tumor necrosis factor α (TNF-α) cytokines in the tumor microenvironment. These cytokines synergistically activated the STAT1/IRF1 axis to trigger tumor cell pyroptosis and the release of large amounts of inflammatory substances and chemokines. Collectively, our findings revealed that CTLA-4 blockade triggered tumor cells pyroptosis via the release of IFN-γ and TNF-α from activated CD8+ T cells, providing a new perspective of ICB.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias de Cabeça e Pescoço , Camundongos , Animais , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Antígeno CTLA-4 , Fator de Necrose Tumoral alfa/metabolismo , Piroptose , Gasderminas , Citocinas/metabolismo , Interferon gama/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Microambiente Tumoral
11.
Oral Oncol ; 138: 106331, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36753904

RESUMO

OBJECTIVES: CD103+CD8+T cells is a subtype of T cells with excellent tumor killing ability and it could response to immune checkpoint blockade therapy in several types of cancer, but the phenotype, role and molecular mechanism CD103+CD8+T cells in the OSCC still unclear. MATERIALS AND METHODS: The distribution and phenotype of CD103+CD8+T cells were investigated by performing multiplexed immunohistochemistry on human OSCC tissue microarray and flow cytometric analysis of fresh OSCC tumor-infiltrating lymphocytes (TILs). By in vivo use of anti-CD103 monoclonal antibody (mAb) in the 4MOSC1 tumor-bearing mouse model, CD103+CD8+T cell infiltration and cytotoxicity was clarified. RESULTS: The majority of CD8+T cells in both human and animal OSCC intra-tumoral region were CD103+CD8+T cells with high expression levels of cytotoxic molecules, which can be impaired by CD103 blockade. In addition, combined use of anti-CD103 mAb with anti-CTLA-4 mAb displayed impaired immune checkpoint blockade therapy efficiency. CONCLUSION: CD103+CD8+T cells are the major intra-tumoral subset of CD8+T cells in both animal and human OSCC, and that CD103+CD8+T cells demonstrate remarkable tumor-infiltrating and tumor-killing properties, thereby CD103+CD8+T cells may critical for anti-CTLA-4 immunotherapy in OSCC.


Assuntos
Inibidores de Checkpoint Imunológico , Neoplasias Bucais , Humanos , Animais , Camundongos , Neoplasias Bucais/metabolismo , Linfócitos T CD8-Positivos , Fenótipo , Imunoterapia , Linfócitos do Interstício Tumoral
12.
Chem Commun (Camb) ; 59(7): 932-935, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36597866

RESUMO

Glutathione-responsive nanogels (CDNPs) crosslinked via crosslinker DBHD with the BRAF inhibitor dabrafenib and the COX2 inhibitor celecoxib were fabricated. The CDNPs can effectively induce tumor cell pyroptosis to activate robust antitumor immunity. Additionally, CDNPs combined with αPD-1 antibody greatly inhibited tumor growth in a melanoma mouse model with a prolonged survival time.


Assuntos
Inibidores de Ciclo-Oxigenase 2 , Melanoma , Camundongos , Animais , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/uso terapêutico , Nanogéis , Piroptose , Melanoma/tratamento farmacológico , Inibidores de Proteínas Quinases , Bioengenharia , Imunoterapia , Oximas , Mutação
13.
Adv Healthc Mater ; 12(7): e2202135, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36479643

RESUMO

Pyroptosis is demonstrated to trigger antitumor immunity and represents a promising new strategy to potentiate cancer immunotherapy. The number of potent pyroptosis inducers, however, is limited and without tumor-targeting capability, which inevitably causes damage in normal tissues. Herein, a small molecular prodrug of paclitaxel-oxaliplatin is rationally synthesized, which can be covalently self-assembled with diselenide-containing cross-linking (Dse11), producing a diselenide nanoprodrug (DSe@POC) to induce pyroptosis for the first time. The diselenide bonds within DSe@POC can be split by high glutathione in the tumor microenvironment (TME) and reactive oxygen species induced by photodynamic therapy, thus possessing excellent TME on-target effects. Additionally, DSe@POC is able to elicit intense pyroptosis to remodel the immunostimulated TME and trigger a robust immune response. Furthermore, combined αPD-1 therapy effectively inhibits the growth of remote tumors through the abscopal effect, amplifies a long-term immune memory response to reject rechallenged tumors, and prolongs survival. Collectively, DSe@POC, as the first TME dual-responsive diselenide-based pyroptosis inducer, will open up an attractive approach for cancer immunotherapy.


Assuntos
Neoplasias , Pró-Fármacos , Humanos , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Piroptose , Paclitaxel/farmacologia , Imunoterapia , Neoplasias/tratamento farmacológico , Microambiente Tumoral
14.
Oral Dis ; 29(1): 175-187, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34651389

RESUMO

OBJECTIVE: Adenoid cystic carcinoma (AdCC) and mucoepidermoid carcinoma (MEC) are the two most frequent malignancies of salivary glands. This study aims to explore the expression and migration of LAG3, TIM3, and A2aR in AdCC and MEC, and the potential relationship with oncogenic signaling molecules and immunosuppressive cytokines. MATERIALS AND METHODS: Custom made human salivary gland tissue microarrays included 81 AdCCs, 52 MECs, 76 normal salivary glands (NSG), and 14 pleomorphic adenoma (PMA) samples. Immunohistochemical analysis of lymphocyte activation gene 3 (LAG3), T-cell immunoglobulin and mucin domain-containing protein 3 (TIM3), adenosine 2a receptor (A2aR), oncogenic phosphorylated S6 kinase (p-S6) and ERK1/2 (p-ERK1/2 ), and TGF-ß1 was performed with salivary gland tissue microarrays of human samples. The correlation of the immunostaining was analyzed based on a digital pathological system, and data were evaluated by hierarchical cluster. Further in vitro studies of knockdown immune checkpoints LAG3, TIM3, and A2aR were carried out by siRNA transfection. RESULTS: The expression levels of LAG3, TIM3, and A2aR were remarkably increased in AdCC and MEC, compared with NSG and PMA samples, but were independent of pathology grade. They were closely correlated with TGF-ß1, slightly related to p-ERK1/2 and p-S6. After the knockdown of immune checkpoints LAG3, TIM3, and A2aR, the migration of SACC-LM cell line was significantly reduced. CONCLUSIONS: These results suggested that LAG3, TIM3, and A2aR are overexpressed in AdCC and MEC, may promote migration of SACC-LM cell and correlated with TGF-ß1 and oncogenic signaling pathways.


Assuntos
Adenoma Pleomorfo , Carcinoma Adenoide Cístico , Carcinoma Mucoepidermoide , Neoplasias das Glândulas Salivares , Humanos , Adenoma Pleomorfo/genética , Carcinoma Adenoide Cístico/genética , Carcinoma Mucoepidermoide/genética , Receptor Celular 2 do Vírus da Hepatite A/genética , Neoplasias das Glândulas Salivares/patologia , Proteína do Gene 3 de Ativação de Linfócitos/genética , Receptor A2A de Adenosina/genética
15.
BMC Microbiol ; 22(1): 321, 2022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-36581836

RESUMO

BACKGROUND: Helicobacter pylori (H. pylori) infection is associated with remodeling of gut microbiota. Many studies have found H. pylori infection and eradication therapy can alter the gut microbiota. However, few studies explored the impact of eradication therapy containing minocycline and metronidazole on gut microbiota. AIM: The objective of the present study was to explore the changes of gut microbiota after H. pylori infection. Besides, learn more about the dynamic changes of gut microbiota during different stages of eradication treatment containing minocycline, metronidazole, bismuth agents and proton pump inhibitors. METHODS: Sixty stool samples from the patients with H. pylori infection before eradication, 14 and 42 days after eradication, and ten stool samples from non-infected individuals were collected. Subsequently, we performed 16S rRNA gene amplicon sequencing to analyze these samples, and the results were evaluated by using alpha diversity, beta diversity and microbial composition analyses. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States was also used to predict the metabolic pathways according to the Kyoto Encyclopedia of Genes and Genomes database. RESULTS: The alpha and beta diversity of the microbiota changed significantly in H. pylori infected individuals, but returned to baseline 42 days after eradication therapy. At the genus level, the abundances of Bacteroidetes, [Ruminococcus]_gnavus_group, Ruminococcaceae_Incertae_Sedis, Tuzzrealla, Butyricicoccus were significantly lower in the H. pylori infected group. Bacterial abundance was also dynamically changing during eradication treatment. In addition, PICRUST analysis found the levels of uronic acid metabolism, uncharacterized transport system, and biosynthesis of unsaturated fatty acids were higher in H. pylori infected individuals than in the non-infected group. CONCLUSIONS: Intestinal microbiota diversity, composition, functional predictions altered significantly after H. pylori infection, and gradually returned to healthy control levels after the application of eradication therapy containing minocycline and metronidazole in one month and a half.


Assuntos
Microbioma Gastrointestinal , Infecções por Helicobacter , Helicobacter pylori , Humanos , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Metronidazol/farmacologia , Metronidazol/uso terapêutico , Minociclina/farmacologia , Minociclina/uso terapêutico , Helicobacter pylori/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , RNA Ribossômico 16S/genética , Filogenia , Quimioterapia Combinada
16.
Proc Natl Acad Sci U S A ; 119(40): e2200835119, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36161936

RESUMO

Ice cores from alpine glaciers are unique archives of past global and regional climate conditions. However, recovering climate records from these ice cores is often hindered by the lack of a reliable chronology, especially in the age range of 100 to 500 anni (a) for which radiometric dating has not been available so far. We report on radiometric 39Ar dating of an ice core from the Tibetan Plateau and the construction of a chronology covering the past 1,300 a using the obtained 39Ar ages. This is made possible by advances in the analysis of 39Ar using the laser-based detection method atom trap trace analysis, resulting in a twofold increase in the upper age limit of 39Ar dating. By measuring the anthropogenic 85Kr along with 39Ar we quantify and correct modern air contamination, thus removing a major systematic uncertainty of 39Ar dating. Moreover, the 85Kr data for the top part of the ice core provide information on firn processes, including the age difference between the ice and its enclosed gas. This first application of 39Ar and 85Kr to an ice core facilitates further ice cores from nonpolar glaciers to be used for recovering climate records of the Common Era, a period including pronounced anomalies such as the Little Ice Age and the Medieval Warm Period.


Assuntos
Camada de Gelo , Datação Radiométrica , Clima , Mudança Climática , Datação Radiométrica/métodos , Tibet
17.
Chem Biol Interact ; 368: 110197, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36174736

RESUMO

Carboxylesterases 1A (CES1A) is a key enzyme responsible for the hydrolytic metabolism of a great deal of endogenous and exogenous substrates bearing ester- or amide-bond(s). This study aimed to decipher the species difference in CES1A-mediated hydrolytic metabolism by using a newly developed bioluminescence CES1A sensor (termed NLMe) as the probe substrate, while the liver microsomes from six different mammalian species (human, cynomolgus monkey, dog, minipig, rat and mouse) were used as the enzyme sources. Metabolite profiling demonstrated that all tested liver microsomes from various species could catalyze NLMe hydrolysis, but significant difference in hydrolytic rate was observed. Kinetic plots of NLMe hydrolysis in liver microsomes from different species showed that the inherent clearance rates (Clint) of NLMe in human liver microsomes (HLM), cynomolgus monkey liver microsomes (CyLM), and pig liver microsome (PLM) were comparable, while the Clint values of NLMe in dog liver microsomes (DLM), mouse liver microsomes (MLM), and rat liver microsomes (RLM) were relatively small. Moreover, chemical inhibition assays showed that NLMe hydrolysis in all tested liver microsomes could be competently inhibited by BNPP (a potent broad-spectrum inhibitor of CES), but CUA (a selective inhibitor of human CES1A) only inhibited NLMe hydrolysis in human liver microsomes and dog liver microsomes. In summary, the species differences in CES1A-catalyzed NLMe hydrolysis were carefully investigated from the views of the similarities in metabolite profile, hydrolytic kinetics and inhibitor response. All these findings provide new insights into the species differences in CES1A-mediated hydrolytic metabolism and suggest that it is necessary for the pharmacologists to choose appropriate animal models to replace humans for evaluating the in vivo effects of CES1A inhibitors.


Assuntos
Hidrolases de Éster Carboxílico , Microssomos Hepáticos , Animais , Cães , Humanos , Camundongos , Ratos , Hidrolases de Éster Carboxílico/metabolismo , Hidrólise , Macaca fascicularis/metabolismo , Mamíferos/metabolismo , Microssomos Hepáticos/metabolismo , Especificidade da Espécie , Suínos , Porco Miniatura/metabolismo
18.
Int Immunopharmacol ; 111: 109113, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35944462

RESUMO

Epigenetic alterations, including DNA methylation, play crucial roles in the tumor. Epigenetic drugs like DNA methyltransferase-1 (DNMT1) inhibitors have been exhibited positive effects in cancer treatment. However, the role of DNMT1 in oral squamous cell carcinoma (OSCC) is less clearly described. What is more, the effects on the immune microenvironment of DNMT1 have not become appreciated. In this research, we determine the expression levels of DNMT1 and the association of prognosis by analyzing human OSCC tissue microarrays. Two different types of immunocompetent mouse OSCC models were established to explore the effects of DNMT1 inhibitor on the tumor microenvironment(TME). We identified DNMT1 was highly expressed both in human and mouse OSCC tissues. The expression levels of DNMT1 was also correlated with the immunosuppressive molecules and tumor-promoter such as VISTA, PD-L1, B7-H4, and PAK2, indicating a worse prognosis. Of particular concern is that DNMT1 inhibition improved TME and delayed tumor growth by decreasing myeloid-derived suppressor cells (MDSCs) and increasing tumor-infiltrating T cells. Our data suggests that DNMT1 play a key role in OSCC and has a possible immunotherapeutic marker treatment.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Animais , Carcinoma de Células Escamosas/genética , Metilação de DNA , Neoplasias de Cabeça e Pescoço/genética , Humanos , Camundongos , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/genética , Neoplasias Bucais/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Microambiente Tumoral
19.
Adv Sci (Weinh) ; 9(26): e2203353, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35869614

RESUMO

Effective pyroptosis induction is a promising approach to potentiate cancer immunotherapy. However, the actual efficacy of the present pyroptosis inducers can be weakened by successive biological barriers. Here, a cascaded pH-activated supramolecular nanoprodrug (PDNP) with a stepwise size shrinkage property is developed as a pyroptosis inducer to boost antitumor immune response. PDNPs comprise multiple poly(ethylene glycol) (PEG) and doxorubicin (DOX) drug-polymer hybrid repeating blocks conjugated by ultra-pH-sensitive benzoic imine (bzi) and hydrazone (hyd) bonds. The PEG units endow its "stealth" property and ensure sufficient tumor accumulation. A sharp switch in particle size and detachment of PEG shielding can be triggered by the acidic extracellular pH to achieve deep intratumor penetration. Following endocytosis, second-stage size switching can be initiated by more acidic endolysosomes, and PDNPs disassociate into ultrasmall cargo to ensure accurate intracellular delivery. The cascaded pH activation of PDNPs can effectively elicit gasdermin E (GSDME)-mediated pyroptosis to enhance the immunological response. In combination with anti-PD-1 antibody, PDNPs can amplify tumor suppression and extend the survival of mice, which suggests a powerful immune adjuvant and pave the way for high-efficiency immune checkpoint blockade therapy.


Assuntos
Neoplasias , Pró-Fármacos , Animais , Doxorrubicina/química , Doxorrubicina/farmacologia , Camundongos , Polietilenoglicóis/química , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Piroptose
20.
Adv Mater ; 34(42): e2204034, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35728795

RESUMO

Immunotherapy is one of the most promising clinical modalities for the treatment of malignant tumors and has shown excellent therapeutic outcomes in clinical settings. However, it continues to face several challenges, including long treatment cycles, high costs, immune-related adverse events, and low response rates. Thus, it is critical to predict the response rate to immunotherapy by using imaging technology in the preoperative and intraoperative. Here, the latest advances in nanosystem-based biomaterials used for predicting responses to immunotherapy via the imaging of immune cells and signaling molecules in the immune microenvironment are comprehensively summarized. Several imaging methods, such as fluorescence imaging, magnetic resonance imaging, positron emission tomography imaging, ultrasound imaging, and photoacoustic imaging, used in immune predictive imaging, are discussed to show the potential of nanosystems for distinguishing immunotherapy responders from nonresponders. Nanosystem-based biomaterials aided by various imaging technologies are expected to enable the effective prediction and diagnosis in cases of tumors, inflammation, and other public diseases.


Assuntos
Materiais Biocompatíveis , Neoplasias , Humanos , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Imunoterapia/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Imageamento por Ressonância Magnética , Fatores Imunológicos , Imunidade , Microambiente Tumoral
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