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1.
Rev Sci Instrum ; 95(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38832851

RESUMO

The widespread use of deep learning in processing point cloud data promotes the development of neural networks designed for point clouds. Point-based methods are increasingly becoming the mainstream in point cloud neural networks due to their high efficiency and performance. However, most of these methods struggle to balance both the geometric and semantic space of the point cloud, which usually leads to unclear local feature aggregation in geometric space and poor global feature extraction in semantic space. To address these two defects, we propose a bilateral feature fusion module capable of combining geometric and semantic data from the point cloud to enhance local feature extraction. In addition, we propose an offset vector attention module for better extraction of global features from point clouds. We provide specific ablation studies and visualizations in the article to validate our key modules. Experimental results show that the proposed method performs superior in both point cloud classification and segmentation tasks.

2.
Cell Death Discov ; 10(1): 238, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762529

RESUMO

Esophageal cancer is a common type of cancer that poses a significant threat to human health. While the pro-inflammatory cytokine IL-1ß has been known to contribute to the development of various types of tumors, its role in regulating esophageal cancer progression has not been extensively studied. Our studies found that the expression of IL-1ß and FOXO3A was increased in esophageal squamous cell carcinoma (ESCC). IL-1ß not only increased the proliferation, migration, and invasion of two ESCC cell lines but also promoted tumor growth and metastasis in nude mice. We also observed that IL-1ß and FOXO3A regulated the process of epithelial-mesenchymal transition (EMT) and autophagy. The PI3K/AKT pathway was found to be involved in the changes of FOXO3A with the expression level of IL-1ß. The AKT agonist (SC79) reversed the reduction of FOXO3A expression caused by the knockdown of IL-1ß, indicating that IL-1ß plays a role through the PI3K/AKT/FOXO3A pathway. Furthermore, the knockdown of FOXO3A inhibited ESCC development and attenuated the pro-cancer effect of overexpressed IL-1ß. Targeting IL-1ß and FOXO3A may be potentially valuable for the diagnosis and treatment of ESCC.

3.
Bioorg Med Chem Lett ; 95: 129493, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37793497

RESUMO

Auristatins-glucuronide conjugates designed targeting the ß-Glucuronidase in tumor microenvironment were synthesized and evaluated on stabilities, the release of auristatins and the antitumor activities in this study. Conjugates 20 and 21 showed remarkable stabilities in phosphate buffer and bovine serum solution, and excellent selectivity between the in vitro antiproliferative activities against ß-glucuronidase pretreated and untreated cancer cells (IC50 = 5.7 nM âˆ¼ 9.7 nM, IC50 (-Enz) > 1 µM). Furthermore, conjugate 20 showed potent antitumor efficacy in HCT-116 xenograft mouse model without inducing side effects.


Assuntos
Glucuronidase , Glucuronídeos , Camundongos , Humanos , Animais , Glucuronídeos/farmacologia , Microambiente Tumoral , Oligopeptídeos/farmacologia
4.
J Org Chem ; 88(15): 11122-11129, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37470346

RESUMO

Three new germacranolide sesquiterpene lactones (SLs), strochunolides A-C (1-3, respectively), and a new guaianolide SL, strochunolide D (4), were isolated from Strobocalyx chunii and structurally characterized. Compound 1 is the first example of a dihomo-germacranolide SL, characterized by an unprecedented 6/10/5 tricyclic scaffold incorporating an additional fused δ-lactone C-ring. The structure of a known germacranolide SL, spicatolide C (5), was revised as its 8-epimer. Compound 3 exhibited potent in vitro cytotoxic activity against the HL-60 cell line, with an IC50 value of 0.18 ± 0.01 µM.


Assuntos
Antineoplásicos , Asteraceae , Sesquiterpenos , Humanos , Antineoplásicos/química , Lactonas/farmacologia , Lactonas/química , Sesquiterpenos/farmacologia , Sesquiterpenos/química
5.
J Med Chem ; 66(10): 7016-7037, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37184921

RESUMO

A novel series of benzamide derivatives were successively designed and synthesized prepared from the pyridazinone scaffold. Among them, (S)-17b, demonstrated potent inhibitory activity in vitro toward human class I HDAC isoforms and human myelodysplastic syndrome (SKM-1) cell line. Also, (S)-17b strongly increased the intracellular level of acetyl-histone H3 and P21 simultaneously and effectively induced G1 cell cycle arrest and apoptosis. Through oral dosing in SKM-1 xenograft models, (S)-17b exhibited excellent in vivo antitumor activity. In addition, compound (S)-17b showed better antitumor efficacy on mouse models with intact immune system than those with thymus deficiencies. Furthermore, this compound displayed a favorable pharmacokinetic profile in ICR mice and SD rat, respectively, minimal metabolic property differences among hepatocytes from five species, and a low inhibition upon the human ether-a-go-go (hERG) channel with an IC50 value of 34.6 µΜ. This novel compound (S)-17b may serve as a new drug candidate for further investigation.


Assuntos
Antineoplásicos , Inibidores de Histona Desacetilases , Camundongos , Humanos , Ratos , Animais , Inibidores de Histona Desacetilases/uso terapêutico , Inibidores de Histona Desacetilases/farmacocinética , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacocinética , Ratos Sprague-Dawley , Camundongos Endogâmicos ICR , Modelos Animais de Doenças , Benzamidas/farmacologia , Proliferação de Células , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Apoptose , Relação Estrutura-Atividade
6.
Cell Death Dis ; 14(3): 230, 2023 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-37002211

RESUMO

Non-small cell lung cancer (NSCLC) is one of the most threatening malignancies to human health and life. In most cases, patients with NSCLC are already at an advanced stage when they are diagnosed. In recent years, lung cancer has made great progress in precision therapy, but the efficacy of immunotherapy is unstable, and its response rate varies from patient to patient. Several biomarkers have been proposed to predict the outcomes of immunotherapy, such as programmed cell death-ligand 1 (PD-L1) expression and tumor mutational burden (TMB). Nevertheless, the detection assays are invasive and demanding on tumor tissue. To effectively predict the outcomes of immunotherapy, novel biomarkers are needed to improve the performance of conventional biomarkers. Liquid biopsy is to capture and detect circulating tumor cells (CTCs), circulating tumor DNA (ctDNA) and exosomes in body fluids, such as blood, saliva, urine, pleural fluid and cerebrospinal fluid as samples from patients, so as to make analysis and diagnosis of cancer and other diseases. The application of liquid biopsy provides a new possible solution, as it has several advantages such as non-invasive, real-time dynamic monitoring, and overcoming tumor heterogeneity. Liquid biopsy has shown predictive value in immunotherapy, significantly improving the precision treatment of lung cancer patients. Herein, we review the application of liquid biopsy in predicting the outcomes of immunotherapy in NSCLC patients, and discuss the challenges and future directions in this field.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Biópsia Líquida , Imunoterapia , Biomarcadores Tumorais/metabolismo , Antígeno B7-H1/metabolismo
7.
J Nat Prod ; 86(1): 209-221, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36583957

RESUMO

Continued efforts to expand the structural diversity of dichapetalins and explore further the cytotoxic structure-activity relationships have led to the isolation of 17 undescribed analogues, dichapelonins A-Q (1-17), and three known compounds (18-20) from the twigs of Dichapetalum longipetalum. Compounds 1-17 comprise five compound classes as classified by varied C6-C2 conjugates at the A ring of the 13,30-cyclodammarane skeleton, and their structures were determined by spectroscopic data analysis, experimental electronic circular dichroism measurements, and X-ray crystallography. Biological tests revealed compounds 1-7 with a phenyl-butadiene appendage to be the most potent cytotoxic compound type of those evaluated.


Assuntos
Antineoplásicos , Estrutura Molecular , Antineoplásicos/farmacologia , Relação Estrutura-Atividade
8.
Mol Carcinog ; 62(2): 122-134, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36193884

RESUMO

New diagnostic and therapeutic strategies are urgently needed to improve the prognosis of patients with esophageal squamous cell carcinoma (ESCC), which has high morbidity and mortality. Bioinformatics analysis revealed that cell cycle regulation related molecular G2 and S phase-expressed-1 (GTSE1) was dysregulated in ESCC. In this study, the ectopic expression of GTSE1 was verified in ESCC patients' tissues and cell lines. After overexpression or knockdown of GTSE1 using lentiviral transfection, the effects of GTSE1 on the proliferation, migration, invasion, and apoptosis of ESCC cells were detected. The contribution of GTSE1 in inducing chromosomal missegregation in cells leading to chromosome instability (CIN) has been described. Long-term existence of CIN can increase reactive oxygen species (ROS) generation in ESCC cells, followed by inhibition of apoptosis by activating the c-Jun N-terminal kinase (JNK) signaling pathway, and this inhibition could be relieved after treatment with JNK inhibitor. In vivo experiments, we also confirmed the tumor-promoting effect and mechanism of GTSE1 in ESCC using nude mice model. In this study, we demonstrated that GTSE1 induces CIN in ESCC cells, and increases intracellular ROS production, which leads to cellular oxidative stress, contributes to the activation of the JNK signaling pathway, and thereby inhibits apoptosis leading to ESCC tumorigenesis.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Animais , Camundongos , Apoptose , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Instabilidade Cromossômica , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/metabolismo , Sistema de Sinalização das MAP Quinases , Camundongos Nus , Espécies Reativas de Oxigênio/metabolismo , Fase S , Humanos
9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(5): 1343-1347, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36208233

RESUMO

OBJECTIVE: To investigate the effects of curcumin on the proliferation, apoptosis, and cell cycle of human acute myeloid leukemia cell line K562. METHODS: MTT method was used to detect the proliferation inhibition of logarithmic growth phase human acute myeloid leukemia K562 cells, flow cytometry was used to detect the cell cycle, Annexin V-FITC was used to detect the apoptosis rate, and real-time fluorescent quantitative PCR and Western blot were used to detect the expression of Bax, BCL-2 and caspase-3 mRNA and protein, respectively. RESULTS: The inhibition rate of cell proliferation in curcumin 10, 20, and 40 µmol/L group for 24 h and 48 h were higher than that in the control group (curcumin 0 µmol/L), and the cell proliferation inhibition rate was concentration-time dependent (r=0.879, r=0.914). The proportion of G0/G1 cells and apoptosis rate of K562 cells in the curcumin 10, 20, and 40 µmol/L group were higher than those in the control group, and showed drug concentration dependent (r=0.856, r=0.782). The expression of Bax and Caspase-3 mRNA in the curcumin 10, 20, and 40 µmol/L group was higher, while BCL-2 mRNA was lower than those in the control group, and showed drug concentration dependent (r=0.861, r=0.748, r=-0.817). The gray value of Bax protein expression in the curcumin 10, 20, and 40 µmol/L group was higher than that in the control group, while the gray value of BCL-2 and Caspase-3 protein expression was lower than that in the control group, and showed drug concentration dependent (r=0.764, r=-0.723, r=-0.831). CONCLUSION: Curcumin can inhibit the proliferation of human acute myeloid leukemia cell line K562 cells, block the cell cycle at G0/G1 phase, promote cell apoptosis, and induce apoptosis by regulating Bax, BCL-2, and Caspase-3.


Assuntos
Curcumina , Leucemia Mieloide Aguda , Apoptose , Caspase 3/metabolismo , Ciclo Celular , Proliferação de Células , Curcumina/farmacologia , Humanos , Células K562 , Leucemia Mieloide Aguda/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/metabolismo , Proteína X Associada a bcl-2/farmacologia
10.
Anal Cell Pathol (Amst) ; 2022: 7005328, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36046597

RESUMO

Objective: To investigate the expression of ATPase family AAA domain-containing protein 2 (ATAD2) and kinesin family member 4A (KIF4A) in esophageal squamous cell carcinoma (ESCC) tissues and their association with clinicopathological features and to explore the role of ATAD2 in regulating KIF4A expression and biological functions in ESCC cells and the effect of aspirin on their expression. Methods: The mRNA and protein expression of ATAD2 and KIF4A in the tissues of patients with ESCC were measured by RT-qPCR and immunohistochemistry, and the correlation between the expression of mRNA and clinicopathological characteristics was analyzed. Western blot and RT-qPCR were used to detect the interference efficiency and KIF4A expression after si-ATAD2 transfection in EC109 and KYSE30 cells. CCK-8 and Transwell assay were performed to investigate the effects of ATAD2 and aspirin on proliferation, migration, and invasion of ESCC cells. The effect of aspirin on the expression of ATAD2 and KIF4A in ESCC cells was measured by RT-qPCR and Western blot. Results: The expression of ATAD2 and KIF4A was upregulated in ESCC tissues, and both were correlated with the differentiation grades and lymph node metastasis. Knockdown of ATAD2 in ESCC cells significantly inhibited cell proliferation, migration, and invasion. Compared to the negative control group, the proliferation, migration, and invasion ability of ESCC cells in the aspirin-treated groups were decreased, and the expression of ATAD2 and KIF4A in ESCC cells was decreased after treating with aspirin for 48 h. Conclusion: The expression levels of ATAD2 and KIF4A are elevated in ESCC. ATAD2 promotes proliferation, migration, and invasion of ESCC cells by regulating KIF4A. Aspirin can inhibit the malignant behavior of ESCC cells by downregulating ATAD2 and KIF4A.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , ATPases Associadas a Diversas Atividades Celulares/genética , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Aspirina/farmacologia , Aspirina/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Cinesinas/genética , Invasividade Neoplásica/genética , RNA Mensageiro
11.
BMC Cancer ; 22(1): 888, 2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-35964022

RESUMO

BACKGROUND: Histocompatibility minor 13 (HM13) is a signal sequence stubbed intramembrane cleavage catalytic protein that is essential for cell signaling, intracellular communication, and cancer. However, the expression of HM13 and its prognostic value, association with tumor-infiltrating immune cells (TIICs) in the microenvironment, and potential to predict immunotherapeutic response in HCC are unknown. METHODS: The HM13 expression, clinicopathology analysis, and its influence on survival were analyzed in multiple public databases and further verified in collected HCC and normal tissues by qRT-PCR and immunohistochemistry staining assay (IHC). Furthermore, the lentivirus vector encoding HM13-shRNA to manipulate HM13 expression was selected to investigate whether HM13 could influence the malignant growth and metastasis potential of HCC cells. Finally, significant impacts of HM13 on the HCC tumor microenvironment (TME) and reaction to immune checkpoint inhibitors were analyzed. RESULTS: Upregulated HM13 was substantially correlated with poor prognosis in patients with HCC, and could facilitate the proliferation and migratory potential of HCC cells. Additionally, patients with high HM13 expression might be more sensitive to immunotherapy. CONCLUSIONS: HM13 might be a prognostic biomarker and potential molecular therapeutic target for HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/terapia , Humanos , Fatores Imunológicos , Imunoterapia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/terapia , Prognóstico , Microambiente Tumoral/genética
12.
Eur J Med Chem ; 236: 114259, 2022 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-35395439

RESUMO

Novel pyrrolopyridone BET degraders were designed and synthesized based on the binding mode between the pyrrolopyridone BET inhibitor with the BRD4 protein. The potent degraders on MV-4-11 cells were discovered through structure-activity relationship study. Modification of warhead on pyrrolopyridone BET degraders significantly regulates BRD4 isoform (long and short) protein degradation, which induces differential cell cycle arrest and apoptosis on MV-4-11 cells. Docking study revealed that the fine structural modification of BET degraders may bind with the BD domain of BRD4 protein to engage various surface areas that bind with CRBN.


Assuntos
Antineoplásicos , Proteínas Nucleares , Antineoplásicos/farmacologia , Proteínas de Ciclo Celular , Proteínas Nucleares/metabolismo , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo
13.
Phytochemistry ; 198: 113142, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35231502

RESUMO

A chemical investigation on the aerial parts of Euphorbia neriifolia led to the identification of thirteen undescribed diterpenoids, phorneroids A-M, including ent-abietane (A-D), ent-kaurane (E-G), ent-atisane (H-K), and ent-isopimarane (L and M) types, together with three known compounds. Phorneroid A represents the first example of 8-spiro-fused 9,10-seco-ent-abietane diterpenoid lactone featuring a unique 6/5/6/5 spirocyclic framework. Biological assays showed that some of the compounds displayed moderate cytotoxicity against two human tumor cell lines, A549 and HL-60.


Assuntos
Diterpenos do Tipo Caurano , Diterpenos , Euphorbia , Linhagem Celular Tumoral , Diterpenos/química , Diterpenos/farmacologia , Diterpenos do Tipo Caurano/química , Euphorbia/química , Estrutura Molecular
14.
Environ Sci Pollut Res Int ; 29(38): 57261-57276, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35349062

RESUMO

Endocrine disrupting compounds (EDCs), such as bisphenol A (BPA) and 17α-ethynylestradiol (EE2), have increasingly negative effects on human and wildlife health. In this study, the biogenic Mn oxides (BMOs) generated by Bacillus sp. WH4 were characterized, and the removal effects and reaction kinetics of BPA and EE2 by BMOs under different pH values, initial organic concentrations, and dosages of BMOs were discussed. The results showed that the formation of BMOs was extracellular process, and Mn(II) was oxidized to Mn(III) and Mn(IV) with 23.56% and 76.44%, respectively. The degradation processes of BPA and EE2 by BMOs followed first-order reaction kinetics, and the removal effect decreased with increasing initial BPA/EE2 concentrations and increased with increasing dosages of BMOs. However, the removal effect of BPA by BMOs decreased and then increased with increasing pH, while the removal effect of EE2 by BMOs decreased with increasing pH. Under optimal conditions, the removal efficiency of BPA and EE2 exceeded 98.2% and 94.3%, respectively. Additionally, this study showed that BMOs degraded BPA by coupling, oxidative condensation, substitution, and elimination reactions to obtain sixteen intermediate products and EE2 by substitution and elimination reactions to obtain seven intermediate products.


Assuntos
Bacillus , Óxidos , Bacillus/metabolismo , Compostos Benzidrílicos/química , Etinilestradiol/química , Humanos , Óxidos/metabolismo , Fenóis/química
15.
Genes Genomics ; 44(5): 603-615, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35305241

RESUMO

BACKGROUND: Differential diagnosis of Crohn's disease (CD) and intestinal tuberculosis (ITB) is still difficult in clinical pratice. DNA methylation has been considered as a favorable area for biomarker exploration and identification. OBJECTIVE: The purpose of the current study was to evaluate DNA methylation changes between CD and ITB. METHODS: We performed a genome-wide association study to identify differentially methylated positions (DMPs), including 8 CD patients (before the initial of biologics or immunomodulators), 6 ITB patients, and 8 healthy controls (HCs), in whole blood DNA using the Infinium HumanMethylation850 BeadChip. RESULTS: Patients in the CD group and ITB group were all observed with hypo-methylated changes compared with HCs. However, the CD group overlaps with the ITB group in DNA methylation, suggesting a stable epigenetic profile between the two diseases. The pathway enrichment analysis showed the alternation in inflammation-related pathway, immune system, and signal transduction. Focused on the DMPs located in the promoter region, further analysis indicated hypermethylation of cg03122532 (5'UTR of KCNJ15) could be a potential CD-specific biomarker. CONCLUSIONS: We identified specific differential methylation loci related to CD and ITB in blood DNA. DNA metylation as a important epigenetic modification could contribute to the pathogenesis study and biomarker exploration of the diseases.


Assuntos
Doença de Crohn , Enterite , Tuberculose Gastrointestinal , Biomarcadores , Doença de Crohn/diagnóstico , Doença de Crohn/genética , DNA , Metilação de DNA/genética , Estudo de Associação Genômica Ampla , Humanos , Tuberculose Gastrointestinal/diagnóstico , Tuberculose Gastrointestinal/genética
16.
ACS Omega ; 7(3): 3052-3059, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35097299

RESUMO

Twelve new members (1-12) of the dolabellane family, co-occurring with three related known diterpenoids (13-15), were isolated from the Xisha soft coral Clavularia viridis. Their structures were determined by extensive spectroscopic analysis, modified Mosher's method, and X-ray diffraction analysis. Clavuperoxylides A (3) and B (4) represent the first examples of dolabellanes containing peroxyl groups, especially the novel peroxide bridge in 4, whereas clavufuranolides A-C (9-11) are the first example of dolabellane diterpenoids comprising a tetrahydrofuran ring. The possible biogenetic relationship of all the isolates was proposed. In bioassay, several compounds exhibited considerable cytotoxicity against A549 and P388 cell lines. Compound 7 exhibited inhibitory activity against protein tyrosine phosphatases 1B (PTP1B), an anti-diabetic target, representing the first report of PTP1B inhibitory activity for dolabellane diterpenoids.

17.
J Nat Prod ; 84(11): 2971-2980, 2021 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-34762434

RESUMO

Fifteen new labdane-type diterpenoids, sublyratins A-O (1-15), along with four known analogues (16-19) were isolated from the aerial parts of Croton sublyratus. Their structural assignments were challenging due to the stereoisomeric features evident and were achieved by analyzing comprehensively the spectroscopic data and electronic circular dichroism spectra and using X-ray crystallographic analysis. Compounds 9 and 16-18 displayed cytotoxic activity against the HL-60 cell line with IC50 values of 1.5-2.8 µM.


Assuntos
Croton/química , Diterpenos/isolamento & purificação , Células A549 , Antineoplásicos Fitogênicos/isolamento & purificação , Diterpenos/química , Diterpenos/farmacologia , Células HL-60 , Humanos
18.
Front Immunol ; 12: 697725, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804004

RESUMO

The intestinal mucosal immune environment requires multiple immune cells to maintain homeostasis. Although intestinal B cells are among the most important immune cells, little is known about the mechanism that they employ to regulate immune homeostasis. In this study, we found that CD11b+ B cells significantly accumulated in the gut lamina propria and Peyer's patches in dextran sulfate sodium-induced colitis mouse models and patients with ulcerative colitis. Adoptive transfer of CD11b+ B cells, but not CD11b-/- B cells, effectively ameliorated colitis and exhibited therapeutic effects. Furthermore, CD11b+ B cells were found to produce higher levels of IgA than CD11b- B cells. CD11b deficiency in B cells dampened IgA production, resulting in the loss of their ability to ameliorate colitis. Mechanistically, CD11b+ B cells expressed abundant TGF-ß and TGF-ß receptor II, as well as highly activate phosphorylated Smad2/3 signaling pathway, consequently promoting the class switch to IgA. Collectively, our findings demonstrate that CD11b+ B cells are essential intestinal suppressive immune cells and the primary source of intestinal IgA, which plays an indispensable role in maintaining intestinal homeostasis.


Assuntos
Linfócitos B/imunologia , Antígeno CD11b/imunologia , Colite Ulcerativa/imunologia , Colite/imunologia , Imunoglobulina A Secretora/imunologia , Nódulos Linfáticos Agregados/imunologia , Transferência Adotiva , Animais , Linfócitos B/patologia , Antígeno CD11b/genética , Colite/induzido quimicamente , Colite/patologia , Colite Ulcerativa/patologia , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Humanos , Switching de Imunoglobulina , Mucosa Intestinal/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nódulos Linfáticos Agregados/patologia , Transdução de Sinais , Proteína Smad2/metabolismo
19.
Bioorg Med Chem Lett ; 51: 128355, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34508844

RESUMO

Plocabulin, a marine natural polyketide isolated from the sponge Lithoplocamia lithistoides, is a novel and potent microtubule-destabilizing agent. Guided by the reported binding mode, several new analogs of plocabulin have been designed through removing the right aliphatic chain and further modifying on the carbamate group and the enamide unit. The preliminary results indicate that the right aliphatic chain in plocabulin is allowed to remove with a little loss of activity, the carbamate group plays a role in the activity, and particularly, the enamide unit has an important effect on the activity. This new finding will aid the design of novel potent tubulin-binding agents based on plocabulin.


Assuntos
Antineoplásicos/farmacologia , Policetídeos/farmacologia , Pironas/farmacologia , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Policetídeos/síntese química , Policetídeos/química , Pironas/síntese química , Pironas/química , Relação Estrutura-Atividade , Moduladores de Tubulina/síntese química , Moduladores de Tubulina/química
20.
Chem Sci ; 12(28): 9831-9838, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34349957

RESUMO

Chemical studies on Dichapetalum gelonioides have afforded 18 highly modified complex triterpenoids belonging to four compound classes as defined by the newly adapted functional motifs associated with the A ring of the molecules. Their structures were determined by solid data acquired by diverse methods. The biosynthetic pathway for the four compound classes was rationalized via cascade modifications involving diverse chemical events. The subsequent biomimetic syntheses afforded all the desired products, including compounds 16 and 19 that were not obtained in our purification, which validated the proposed biosynthetic pathway. Besides, some compounds exhibited strong cytotoxic activities, especially 2 and 4 showed nanomolar potency against the NAMALWA tumor cell line, and a gross structure-activity relationship (SAR) of these compounds against the tested tumor cell lines was delineated.

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