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1.
Int J Mol Sci ; 24(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37894759

RESUMO

Monitoring the microenvironment within specific cellular regions is crucial for a comprehensive understanding of life events. Fluorescent probes working in different ranges of pH regions have been developed for the local imaging of different pH environments. Especially, rhodamine-based fluorescent pH probes have been of great interest due to their ON/OFF fluorescence depending on the spirolactam ring's opening/closure. By introducing the N-alkyl-hydroxamic acid instead of the alkyl amines in the spirolactam of rhodamine, we were able to tune the pH range where the ring opening and closing of the spirolactam occurs. This six-membered cyclic hydroxamate spirolactam ring of rhodamine B proved to be highly fluorescent in acidic pH environments. In addition, we could monitor pH changes of lysosomes in live cells and zebrafish.


Assuntos
Corantes Fluorescentes , Peixe-Zebra , Animais , Concentração de Íons de Hidrogênio , Rodaminas , Lisossomos
2.
Bioorg Med Chem Lett ; 57: 128504, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34922027

RESUMO

Two new fusicoccane-type diterpenoids, streptooctatins A (1) and B (2), together with a known compound cyclooctatin (3) were isolated from Streptomyces sp. KCB17JA11. The structures of 1 and 2 were determined by analyzing spectroscopic and spectrometric data from 1D and 2D NMR and HRESIMS experiments. Compounds 1 and 2 induced EGFP-LC3 puncta indicating autophagic activities against HeLa cells without cytotoxicity.


Assuntos
Autofagia/efeitos dos fármacos , Diterpenos/farmacologia , Streptomyces/química , Diterpenos/química , Diterpenos/isolamento & purificação , Células HeLa , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Estrutura Molecular , Estereoisomerismo
3.
J Nat Prod ; 85(10): 2445-2453, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-36197044

RESUMO

A new secondary metabolite, ulleungdolin (1), was isolated from the co-culture of an actinomycete, Streptomyces sp. 13F051, and a fungus, Leohumicola minima 15S071. Based on the NMR, UV, and MS data, it was deduced that the planar structure of 1 comprised an isoindolinone (IsoID) with an octanoic acid, a tripeptide, and a sugar. The tripeptide has the unprecedented amino acids norcoronamic acid, 3-hydroxy-glutamine, and 4-hydroxy-phenylglycine and is linked by a C-N bond with IsoID. The absolute configurations were determined by chemical derivatization, extensive spectroscopic methods, and electronic circular dichroism calculations and supported by bioinformatic analyses. Bioactivity evaluation studies indicated that 1 had an antimigration effect on MDA-MB-231 breast cancer cells.


Assuntos
Ascomicetos , Policetídeos , Streptomyces , Streptomyces/química , Policetídeos/farmacologia , Policetídeos/química , Técnicas de Cocultura , Estrutura Molecular , Peptídeos
4.
J Nat Prod ; 84(9): 2420-2426, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34455777

RESUMO

Three new trichostatin analogues, ulleunganilines A-C (1-3), and seven known trichostatins (4-10) were isolated from cultures of Streptomyces sp. 13F051. NMR, UV, and MS data indicated that the planar structures of 1-3 consisted of modified side chains in the trichostatic acid moiety. The absolute configuration of the 2,4-dimethyl-branched carbon chains in 1 and 2 was determined by the PGME method, while the amino acid group in 3 was identified by advanced Marfey's method. Based on the structure of the modified side chains, the origin of 1-3 is proposed. Further experiments indicated that 1 and 3 displayed moderate histone deacetylase inhibitory activity, suggesting that not only the hydroxamate group but also the N,N-dimethyl group were essential for the inhibitory activity.


Assuntos
Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Linhagem Celular Tumoral , Inibidores de Histona Desacetilases/isolamento & purificação , Humanos , Ácidos Hidroxâmicos/isolamento & purificação , Estrutura Molecular , República da Coreia , Microbiologia do Solo , Streptomyces/química
5.
J Adv Nurs ; 77(2): 608-621, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33222278

RESUMO

AIMS: To identify the components of transition programs for the successful transition of adolescents and young adults with spina bifida and to synthesize the literature findings on the transition outcomes of the programs. DESIGN: Mixed-methods systematic review. DATA SOURCES: PubMed, CINAHL, PsycINFO, and Web of Science (January 2010-June 2019). REVIEW METHODS: The methodological quality was appraised using the Mixed Methods Appraisal Tool and Cochrane Risk of Bias Tool. Extracted data were summarized as tables. For data synthesis, a sequential explanatory design was used. RESULTS: Eight studies were selected. The main components of the transition programs identified the participants' characteristics and intervention strategies. Quantitative studies reported only positive transition outcomes, including independence and satisfaction with social support and transition experience, whereas negative outcomes such as negative experiences communicating with providers and uncertainty were further reported in qualitative studies. CONCLUSION: For development and implementation of a successful transition program, it is necessary to assess the characteristics and needs of the participants and incorporate their needs with input from parents and trained healthcare providers. IMPACT: When planning transition programs, a comprehensive effort that encompasses program development, implementation, and evaluation, based on developmental tasks and long-term perspectives, is needed. Transition program that reflect the cultural characteristics of Eastern and developing countries are needed.


Assuntos
Disrafismo Espinal , Cuidado Transicional , Adolescente , Pessoal de Saúde , Humanos , Pais , Pesquisa Qualitativa , Apoio Social , Adulto Jovem
6.
Chembiochem ; 21(16): 2253-2258, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32212411

RESUMO

Xylaria species are prolific natural product producers. Here, we report the characterization of a new glycosylated incisterol derivative, called xyloneside A (1) and two known lignans (2 and 3) from the ascomycetous Xylaria sp. FB. The structure of xyloneside A (1) was determined by 1D and 2D NMR spectroscopy, high-resolution electrospray ionization mass spectrometry and electronic circular dichroism measurements. Xyloneside A is composed of a 1,2,3,4,5,10,19-heptanorergosterane skeleton and a ß-D-mannopyranose moiety. This is the first report of an incisterol derivative from an Ascomycete. The biological effects of the isolated metabolites on cytotoxicity, autophagy, cell-migration, and angiogenesis were evaluated.


Assuntos
Antineoplásicos/química , Xylariales/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Glicosilação , Humanos
7.
Bioorg Med Chem Lett ; 30(7): 127005, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32046902

RESUMO

Two new macrolide metabolites of the hygrolidin family, catenulisporidins A and B (1 and 2), together with a known compound hygrolidin (3), were isolated from the culture broth of the rare actinobacterium Catenulispora sp. KCB13F192. Their structures were elucidated on the basis of HRESIMS spectrometric and NMR spectroscopic analyses. Catenulisporidins A and B are the first example of natural hygrolidin and bafilomycin derivatives featuring a modified macrolide ring, and catenulisporidin A possesses a tetrahydrofuran ring through an ether linkage between C-7 and C-10. In cell-based fluorescent imaging and immunoblot assays, the three compounds were shown to inhibit autophagic flux in HeLa cells.


Assuntos
Macrolídeos/farmacologia , Actinobacteria/química , Autofagia/efeitos dos fármacos , Células HeLa , Humanos , Macrolídeos/química , Macrolídeos/isolamento & purificação , Estrutura Molecular
8.
J Enzyme Inhib Med Chem ; 34(1): 1481-1488, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31423846

RESUMO

Indoleamine 2,3-dioxygenase 1 (IDO1), a tryptophan catabolising enzyme, is known as a tumour cell survival factor that causes immune escape in several types of cancer. Flavonoids of Sophora flavescens have a variety of biological benefits for humans; however, cancer immunotherapy effect has not been fully investigated. The flavonoids (1-6) isolated from S. flavescens showed IDO1 inhibitory activities (IC50 4.3-31.4 µM). The representative flavonoids (4-6) of S. flavescens were determined to be non-competitive inhibitors of IDO1 by kinetic analyses. Their binding affinity to IDO1 was confirmed using thermal stability and surface plasmon resonance (SPR) assays. The molecular docking analysis and mutagenesis assay revealed the structural details of the interactions between the flavonoids (1-6) and IDO1. These results suggest that the flavonoids (1-6) of S. flavescens, especially kushenol E (6), as IDO1 inhibitors might be useful in the development of immunotherapeutic agents against cancers.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Sophora/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Células HeLa , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Modelos Moleculares , Estrutura Molecular , Mutagênese Sítio-Dirigida , Relação Estrutura-Atividade , Células Tumorais Cultivadas
9.
J Pediatr Nurs ; 47: e36-e44, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31036384

RESUMO

PURPOSE: This study aimed to determine the needs of children with spina bifida (SB) and their families from their parents' perspective in South Korea. DESIGN AND METHODS: This was a convergent mixed methods study design. From December 2016 to February 2017, parents of children with SB participated in a quantitative prospective observational study (N = 164), using the Family Needs Assessment Tool. Qualitative focus group interviews were conducted, according to three developmental stages (N = 15) in May 2017. Integrated analyses were conducted jointly by merging the quantitative and qualitative findings. RESULTS: Quantitative findings revealed very high parental needs in three assessment domains: information, healthcare service/program, and difficulties related to healthcare. Ten qualitative themes were identified in these 3 domains. Quantitative and qualitative methods enabled more extensive findings. Comparison and merging of the data resulted in six confirmed and four expanded findings. In particular, we identified the need for a child-focused self-management program, a bladder/bowel disability awareness program, welfare policies, and partnership with healthcare professionals as the expanded findings. CONCLUSION: This mixed method study provided empirical evidence to help better understand the complex needs of parents of children with SB. PRACTICE IMPLICATIONS: When developing and providing healthcare education and service to families of children with SB, especially, in countries where SB educational programs have not been established yet, it is important to develop them based on their own needs, which may vary based on the child's developmental stage and socio-cultural characteristics.


Assuntos
Avaliação das Necessidades , Pais/educação , Disrafismo Espinal/enfermagem , Adulto , Criança , Pré-Escolar , Feminino , Grupos Focais , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , República da Coreia , Inquéritos e Questionários
10.
J Nat Prod ; 81(10): 2205-2211, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30251851

RESUMO

The advances of genomic sequence analyses and genome mining tools have enabled the exploration of untapped microbial natural products. Through genome mining studies to discover cryptic natural products, we found biosynthetic genes encoding a new lasso peptide in the genome sequence of a soil bacterium, Streptomyces sp. KCB13F003 isolated from Ulleung Island (a small volcanic island), Korea. The production and purification of the encoded peptide, named ulleungdin, were achieved by optimizing the culture conditions followed by LC-MS-targeted isolation. Structure elucidation was performed by NMR spectroscopic and MS spectrometric analyses and chemical means (Marfey's and GITC derivatizations), proving ulleungdin to be a new 15-mer class II lasso peptide with a threaded structure. Biological evaluation with the cell invasion assay and time-lapse cell tracking analysis revealed that ulleungdin has significant inhibitory activities against cancer cell invasion and migration.


Assuntos
Movimento Celular/efeitos dos fármacos , Mineração de Dados/métodos , Genômica/métodos , Neoplasias/tratamento farmacológico , Peptídeos/farmacologia , Células A549 , Fermentação , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Invasividade Neoplásica , Neoplasias/patologia , Peptídeos/química , República da Coreia , Streptomyces/química
11.
J Nat Prod ; 81(4): 806-810, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29513529

RESUMO

Two new cyclic peptides, pentaminomycins A (1) and B (2), were isolated from cultures of Streptomyces sp. RK88-1441. Based on the interpretation of the NMR, UV, IR, and MS data, the planar structures of 1 and 2 were elucidated as cyclic pentapeptides with a modified amino acid residue, N5-hydroxyarginine (N5-OH-Arg). The absolute configurations of the constituent amino acid residues were determined by the advanced Marfey's method. Localization of l- and d-amino acids in the sequence was ascertained by chiral analysis of the fragment peptide obtained from a partial hydrolysate; amino acids were identified by LC-MS. Pentaminomycin A (1) reduced α-MSH-stimulated melanin synthesis by suppressing the expression of melanogenic enzymes including tyrosinase, tyrosinase-related protein-1 (TRP-1), and tyrosinase-related protein-2 (TRP-2).


Assuntos
Peptídeos Cíclicos/química , Streptomyces/química , Arginina/química , Cromatografia Líquida/métodos , Ressonância Magnética Nuclear Biomolecular/métodos , Espectrometria de Massas em Tandem/métodos
12.
J Nat Prod ; 81(9): 2004-2009, 2018 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-30207722

RESUMO

A chemical investigation of a culture extract from a soil-derived Streptomyces sp. RK88-1441 led to the isolation and characterization of two new glycosylated anthraquinones, aturanosides A (1) and B (2), and a new anthraquinone derivative, aturanocin (3). The structures of these compounds were elucidated by detailed NMR and MS spectroscopic analyses. The absolute configurations of the sugar units, based on the magnitudes of the coupling constants, ROESY correlations, and chemical derivatization, from 1 and 2 are 6- O-[ N-acetyl-α-d-glucosamino-(1→2)-α-l-rhamnoside] and 6- O-α-l-rhamnoside, respectively. Compounds 1 and 2 showed no cytotoxicity against human umbilical vein endothelial cells (HUVECs), but significantly suppressed vascular endothelial growth factor (VEGF)-induced tube formation and invasion of HUVECs. The down-regulation of both the phosphorylation of VEGF receptor 2 and the expression of vascular endothelial cadherin at the protein level were also observed.


Assuntos
Inibidores da Angiogênese/isolamento & purificação , Antraquinonas/isolamento & purificação , Microbiologia do Solo , Streptomyces/metabolismo , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Antraquinonas/química , Antraquinonas/farmacologia , Células Cultivadas , Glicosídeos/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Espectroscopia de Ressonância Magnética
13.
J Nat Prod ; 80(5): 1378-1386, 2017 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-28406643

RESUMO

A bioassay-guided investigation in conjunction with chemical screening led to the isolation of three new glycosides, ulleungoside (1), 2-methylaminobenzoyl 6-deoxy-α-l-talopyranoside (2), and naphthomycinoside (3), along with three known secondary metabolites (5-7) from Streptomyces sp. KCB13F030. Their structures were elucidated by detailed NMR and MS spectroscopic analyses. Absolute configurational analysis of the sugar units based on the magnitudes of the coupling constants, NOESY correlations, chemical derivatization, and optical rotation measurements revealed that compounds 1-3 and 5 incorporate the rare deoxyhexose 6-deoxy-α-l-talopyranose. The absolute configuration of a polyketide extender unit of 3 was determined by applying the J-based configuration analysis and modified Mosher's method. Ulleungoside (1) and naphthomycin A (7) showed in vitro inhibitory effects against indoleamine 2,3-dioxygenase activity. Further bioevaluation revealed that compounds 1 and 7 had moderate antiproliferative activities against several cancer cell lines, and compounds 5 and 6, which are members of the piericidin family, induced autophagosome accumulation.


Assuntos
Glicosídeos/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Indolamina-Pirrol 2,3,-Dioxigenase/química , Indolamina-Pirrol 2,3,-Dioxigenase/isolamento & purificação , Naftoquinonas/química , Naftoquinonas/isolamento & purificação , Policetídeos/química , Streptomyces/química , ortoaminobenzoatos/química , Bioensaio , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Naftoquinonas/farmacologia , Ressonância Magnética Nuclear Biomolecular , Policetídeos/isolamento & purificação , Policetídeos/farmacologia , ortoaminobenzoatos/isolamento & purificação , ortoaminobenzoatos/farmacologia
14.
J Nat Prod ; 80(11): 3025-3031, 2017 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-29083895

RESUMO

Analysis of the genome sequence of Streptomyces sp. KCB13F003 showed the presence of a cryptic gene cluster encoding flavin-dependent halogenase and nonribosomal peptide synthetase. Pleiotropic approaches using multiple culture media followed by LC-MS-guided isolation and spectroscopic analysis enabled the identification of two new chlorinated cyclic hexapeptides, ulleungmycins A and B (1 and 2). Their structures, including absolute configurations, were determined by 1D and 2D NMR techniques, advanced Marfey's analysis, and GITC derivatization. The new peptides, featuring unusual amino acids 5-chloro-l-tryptophan and d-homoleucine, exhibited moderate antibacterial activities against Gram-positive pathogenic bacteria including methicillin-resistant and quinolone-resistant Staphylococcus aureus.


Assuntos
Peptídeos Cíclicos/isolamento & purificação , Streptomyces/química , Sequência de Aminoácidos , Antibacterianos/química , Cromatografia Líquida , Flavinas/metabolismo , Genômica , Bactérias Gram-Positivas/efeitos dos fármacos , Hidrocarbonetos Clorados , Resistência a Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Oxirredutases/metabolismo , Peptídeo Sintases/metabolismo , Peptídeos Cíclicos/química , Infecções Estafilocócicas , Staphylococcus aureus/efeitos dos fármacos , Streptomyces/genética , Triptofano/metabolismo
15.
Mar Drugs ; 14(4)2016 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-27049393

RESUMO

Salterns, one of the most extreme natural hypersaline environments, are a rich source of halophilic and halotolerant microorganisms, but they remain largely underexplored ecological niches in the discovery of bioactive secondary metabolites. In continued efforts to investigate the metabolic potential of microbial populations from chemically underexplored sites, three new lipopeptides named iturin F1, iturin F2 and iturin A9 (1-3), along with iturin A8 (4), were isolated from Bacillus sp. KCB14S006 derived from a saltern. The structures of the isolated compounds were established by 1D-, 2D-NMR and HR-ESIMS, and their absolute configurations were determined by applying advanced Marfey's method and CD spectroscopy. All isolates exhibited significant antifungal activities against various pathogenic fungi and moderate cytotoxic activities toward HeLa and src(ts)-NRK cell lines. Moreover, in an in vitro enzymatic assay, compound 4 showed a significant inhibitory activity against indoleamine 2,3-dioxygenase.


Assuntos
Bacillus/química , Bacillus/metabolismo , Lipopeptídeos/química , Lipopeptídeos/farmacologia , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Linhagem Celular Tumoral , Fungos/efeitos dos fármacos , Células HeLa , Humanos , Espectroscopia de Ressonância Magnética/métodos
16.
Arch Pharm Res ; 47(3): 272-287, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38416389

RESUMO

Gymnopilus orientispectabilis, also known as "big laughter mushroom," is a hallucinogenic poisonous mushroom that causes excessive laughter upon ingestion. From the fruiting bodies of G. orientispectabilis, eight lanostane-type triterpenoids (1-8), including seven novel compounds: gymnojunols A-G (2-8), were isolated. The chemical structures of these new compounds (2-8) were determined by analyzing their 1D and 2D NMR spectra and HR-EISMS, and their absolute configurations were unambiguously assigned by quantum chemical ECD calculations and a computational method coupled with a statistical procedure (DP4+). Upon evaluating autophagic activity, compounds 2, 6, and 7 increased LC3B-II levels in HeLa cells to a similar extent as bafilomycin, an autophagy inhibitor. In contrast, compound 8 decreased the levels of both LC3B-I and LC3B-II, and a similar effect was observed following treatment with rapamycin, an autophagy inducer. Our findings provide experimental evidence for new potential autophagy modulators in the hallucinogenic poisonous mushroom G. orientispectabilis.


Assuntos
Agaricales , Venenos , Triterpenos , Humanos , Triterpenos/farmacologia , Triterpenos/química , Venenos/análise , Estrutura Molecular , Células HeLa , Agaricales/química , Carpóforos/química
17.
ACS Appl Bio Mater ; 5(5): 2232-2239, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35446530

RESUMO

Acetylcholinesterase (AChE) is a pivotal enzyme that is closely related with multiple neurological diseases, such as brain disorders or alterations in the neurotransmission and cancer. The development of convenient methods for imaging AChE activity in biological samples is very important to understand its mechanisms and functions in a living system. Herein, a fluorescent probe exhibiting emission in the near-infrared (NIR) region is developed to detect AChE and visualize biological AChE activities. This probe exhibits a quick response time, reasonable detection limit, and a large Stokes shift accompanied by the NIR emission. The probe has much better reactivity toward AChE than butyrylcholinesterase, which is one of the significant interfering substances. The outstanding specificity of the probe is proved by cellular imaging AChE activity and successful mapping in different regions of zebrafish. Such an effective probe can greatly contribute to ongoing efforts to design emission probes that have distinct properties to assay AChE in biological systems.


Assuntos
Acetilcolinesterase , Peixe-Zebra , Animais , Butirilcolinesterase , Corantes Fluorescentes , Imagem Óptica
18.
Life (Basel) ; 12(2)2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35207525

RESUMO

Programmed cell death ligand 1 (PD-L1) is an immune checkpoint molecule that inhibits immune responses. The physiological and prognostic role of the PD-L1 signaling pathway in the oral maxillofacial region is unclear. This study aimed to investigate the role of PD-L1 in the progression of oral squamous cell carcinoma (OSCC). Furthermore, clinicopathological factors related to PD-L1 expression were examined in patients with OSCC through immunohistochemistry (IHC) of tissue sections and through an in vitro study in OSCC cells. The medical records, radiographic findings, and mortality referrals of 81 patients obtained from the National Statistical Office were reviewed. IHC was performed on tissue specimens of these patients to determine the expression levels of PD-L1, which showed significant statistical differences based on age, tumor size, TNM stage, cervical lymph node metastasis, and locoregional recurrence. Patients with a high PD-L1 expression had significantly poorer survival rates. Multivariate analysis using the Cox proportional model confirmed the high relative risk ratio for high PD-L1 expression, TNM stage, and neck node metastasis, all of which were significantly associated with a poor prognosis in patients with OSCC. The in vitro study showed that SAS and YD38 cells transfected with PD-L1 siRNA had significantly increased apoptosis, reduced proliferative capacity, and tumorigenicity.

19.
J Microbiol Biotechnol ; 32(3): 302-306, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35058400

RESUMO

A chemical investigation of a culture extract from Streptomyces sp. RK85-270 led to the isolation and characterization of two new oxindoles, RK-270D (1) and E (2). The structures of 1 and 2 were determined by analyzing spectroscopic and spectrometric data from 1D and 2D NMR and High-resolution electrospray ionization mass spectrometry (HRESIMS) experiments. Compound 1 exhibited anti-angiogenic activities against human umbilical vein endothelial cells (HUVECs) without cytotoxicity. Results of Western blot analysis revealed that 1 inhibits VEGF-induced angiogenesis in the HUVECs via VEGFR2/ p38 MAPK-mediated pathway.


Assuntos
Streptomyces , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Oxindóis/metabolismo , Oxindóis/farmacologia
20.
Eur J Pharmacol ; 923: 174938, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35381263

RESUMO

Kurarinone (KR), a naturally occurring flavonoid in Sophora flavescens Aiton and a traditional herbal medicine, reportedly has anti-cancer activity against various cancer types both in vitro and in vivo. However, the cellular mechanism of KR remains unknown. Therefore, we aimed to elucidate the mechanism of cell cycle arrest induced by KR in human colorectal cancer cells. KR not only reduced cell proliferation but also induced G0/G1 arrest of colorectal cancer cell lines. The results of western blotting analysis showed that KR reduced the protein levels of cyclin D1/D3 and CDK4/6 by downregulating signaling proteins such as K-RAS, c-MYC, and p-extracellular signal-regulated kinase. Additionally, KR arrested the cell cycle in the G0/G1 phase in a p53-independent manner, and decreased the protein level of K-RAS by proteasomal degradation dependent on WDR76, an E3 ubiquitin ligase. From these results, we propose that KR could be a potent anti-cancer agent, acting through the degradation of K-RAS dependent on WDR76, regardless of the p53 status.


Assuntos
Proteínas de Ciclo Celular , Neoplasias Colorretais , Proteínas de Ligação a DNA , Flavonoides , Apoptose , Ciclo Celular , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Proteínas de Ligação a DNA/metabolismo , Flavonoides/farmacologia , Pontos de Checagem da Fase G1 do Ciclo Celular , Humanos , Proteínas Proto-Oncogênicas p21(ras) , Proteína Supressora de Tumor p53/metabolismo
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