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1.
Math Biosci Eng ; 21(2): 2024-2049, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38454673

RESUMO

Accurate classification and segmentation of polyps are two important tasks in the diagnosis and treatment of colorectal cancers. Existing models perform segmentation and classification separately and do not fully make use of the correlation between the two tasks. Furthermore, polyps exhibit random regions and varying shapes and sizes, and they often share similar boundaries and backgrounds. However, existing models fail to consider these factors and thus are not robust because of their inherent limitations. To address these issues, we developed a multi-task network that performs both segmentation and classification simultaneously and can cope with the aforementioned factors effectively. Our proposed network possesses a dual-branch structure, comprising a transformer branch and a convolutional neural network (CNN) branch. This approach enhances local details within the global representation, improving both local feature awareness and global contextual understanding, thus contributing to the improved preservation of polyp-related information. Additionally, we have designed a feature interaction module (FIM) aimed at bridging the semantic gap between the two branches and facilitating the integration of diverse semantic information from both branches. This integration enables the full capture of global context information and local details related to polyps. To prevent the loss of edge detail information crucial for polyp identification, we have introduced a reverse attention boundary enhancement (RABE) module to gradually enhance edge structures and detailed information within polyp regions. Finally, we conducted extensive experiments on five publicly available datasets to evaluate the performance of our method in both polyp segmentation and classification tasks. The experimental results confirm that our proposed method outperforms other state-of-the-art methods.


Assuntos
Neoplasias do Colo , Aprendizagem , Humanos , Neoplasias do Colo/diagnóstico por imagem , Fontes de Energia Elétrica , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Semântica
2.
Molecules ; 28(3)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36770929

RESUMO

Prostate adenocarcinoma (PRAD) is the most frequent malignancy, and is the second leading cause of death due to cancer in men. Thus, new prognostic biomarkers and drug targets for PRAD are urgently needed. As we know, nuclear receptor Nur77 is important in cancer development and changes in the tumor microenvironment; whereas, the function of Nur77 in PRAD remains to be elucidated. The TCGA database was used to explore the Nur77 expression and its role in the prognosis of PRAD. It was shown that Nur77 was down regulated in PRAD, and low Nur77 expression was correlated with advanced clinical pathologic characteristics (high grade, histological type, age) and poor prognosis. Furthermore, key genes screening was examined by univariate Cox analysis and Kaplan-Meier survival. Additionally, Nur77 was closely related to immune infiltration and some anti-tumor immune functions. The differentially expressed genes (DEGs) were presented by protein-protein interaction (PPI) network analysis. Therefore, the expression level of Nur77 might help predict the survival of PRAD cases, which presents a new insight and a new target for the treatment of PRAD. In vitro experiments verified that natural product malayoside targeting Nur77 exhibited significant therapeutic effects on PRAD and largely induced cell apoptosis by up-regulating the expression of Nur77 and its mitochondrial localization. Taken together, Nur77 is a prognostic biomarker for patients with PRAD, which may refresh the profound understanding of PRAD individualized treatment.


Assuntos
Adenocarcinoma , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares , Neoplasias da Próstata , Humanos , Masculino , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Biomarcadores , Prognóstico , Próstata , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Microambiente Tumoral/genética , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética
3.
Fitoterapia ; 162: 105288, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36058473

RESUMO

A new pentacyclic triterpenoid, 2-hydroxy-1-ene-hydroxyhopanone (19), and a new benzoxepin-5-one, 3-(4-methyl-3-penten-1-yl)-6-hydroxy-9-methoxy-2H-1-benzoxepin-5-one (25), along with 26 known compounds (1-18, 20-24, 26-28), were isolated from the roots of Arnebia euchroma (Royle) Johnst. The structures of the new compounds were elucidated by extensive spectroscopic analyses. The absolute configurations of shikonofurans 9-13 were determined by quantum chemical ECD calculations and CD spectra comparison for the first time. Pharmacological study revealed that naphthoquinones 1-5, 7, and 8 had obvious cytotoxicity toward human lung adenocarcinoma A549 cell line. Meanwhile, the hypoglycemic and lipid-lowering effects of isolated compounds were assessed by checking their inhibitory effects on key enzymes regulating glucose and lipid metabolism. Results showed that compounds 1, 3, 5, 6, 8, 18, and 19 could inhibit the activity of ATP-citrate lyase (ACL); compound 7 could inhibit the activity of acetyl-CoA carboxylase (ACC1); while compounds 8 and 19 showed inhibitory effects on protein tyrosine phosphatase 1B (PTP1B). Among them, the naphthoquinone 6, steroid 18, and triterpenoid 19 showed moderate inhibitory effects on ACL and PTP1B, but didn't exhibit obvious cytotoxicity. This study demonstrated that compounds 6, 18, and 19 show great promising for the development of new agents for the treatment of metabolic diseases.


Assuntos
Benzoxepinas , Boraginaceae , Naftoquinonas , Triterpenos , Acetil-CoA Carboxilase/metabolismo , Trifosfato de Adenosina/metabolismo , Benzoxepinas/metabolismo , Boraginaceae/química , Glucose/metabolismo , Humanos , Hipoglicemiantes/farmacologia , Lipídeos , Estrutura Molecular , Naftoquinonas/química , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Triterpenos/metabolismo
4.
J Org Chem ; 87(19): 13270-13279, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36131357

RESUMO

Five new unusual citrinin-derived alkaloids with a tetracyclic core, citrinidines A-E (1-5), two new amide alkaloids, methyl (2S,8E)-1'-(2-methyl-3-oxodec-8-enamido) butanoate (6) and (2S,8E)-2-methyl-3-oxodec-8-enamide (7), a new unusual citrinin trimer, tricitrinol C (8), a new citrinin acetal-ketal derivative, citrininol (9), together with four known citrinin monomers (10-13), and three known citrinin dimers (14-16), were isolated from the fermentation of hydrothermal vent-associated fungus Penicillium citrinum TW132-59. Their structures were unambiguously determined by nuclear magnetic resonance (NMR), mass spectrometry, Mosher's method, 13C NMR calculation in combination with DP4+, and ECD calculations. A plausible biosynthetic pathway of all new compounds (1-9) was proposed. Citrinin trimer (8) exhibited potent cytotoxicity activity with an IC50 value of 1.34 ± 0.11 µM, and compounds 1 and 15 showed moderate cytotoxicity with IC50 values of 17.50 ± 1.43 and 9.45 ± 0.55 µM, respectively, against A549 cell line.


Assuntos
Alcaloides , Antineoplásicos , Citrinina , Fontes Hidrotermais , Penicillium , Acetais , Alcaloides/química , Alcaloides/farmacologia , Amidas , Antineoplásicos/química , Citrinina/química , Citrinina/farmacologia , Fungos , Estrutura Molecular , Penicillium/química
5.
Acta Pharm Sin B ; 12(3): 1339-1350, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35530159

RESUMO

DNA damage response (DDR) is a highly conserved genome surveillance mechanism that preserves cell viability in the presence of chemotherapeutic drugs. Hence, small molecules that inhibit DDR are expected to enhance the anti-cancer effect of chemotherapy. Through a recent chemical library screen, we identified shikonin as an inhibitor that strongly suppressed DDR activated by various chemotherapeutic drugs in cancer cell lines derived from different origins. Mechanistically, shikonin inhibited the activation of ataxia telangiectasia mutated (ATM), and to a lesser degree ATM and RAD3-related (ATR), two master upstream regulators of the DDR signal, through inducing degradation of ATM and ATR-interacting protein (ATRIP), an obligate associating protein of ATR, respectively. As a result of DDR inhibition, shikonin enhanced the anti-cancer effect of chemotherapeutic drugs in both cell cultures and in mouse models. While degradation of ATRIP is proteasome dependent, that of ATM depends on caspase- and lysosome-, but not proteasome. Overexpression of ATM significantly mitigated DDR inhibition and cell death induced by shikonin and chemotherapeutic drugs. These novel findings reveal shikonin as a pan DDR inhibitor and identify ATM as a primary factor in determining the chemo sensitizing effect of shikonin. Our data may facilitate the development of shikonin and its derivatives as potential chemotherapy sensitizers through inducing ATM degradation.

6.
Bioengineered ; 13(3): 7238-7252, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35266447

RESUMO

As a staple chemotherapy medicine, cisplatin (DDP) is extensively applied in cancer patients, but its drug resistance is limited. Numerous studies have elucidated that long non-coding RNA (lncRNA) performs as a pivotal agent in osteosarcoma (OS). Nevertheless, lncRNA long intergenic non-coding 00641 (LINC00641)'s functions in DDP resistance for OS remain obscure. The purpose of this study was to investigate the effect and mechanism of LINC00641 on drug resistance of OS. The tissues of both clinical cancer patients and the normal control were gathered. Detection of LINC00641, microRNA-320d (miR-320d) and myeloid cell leukemia-1 (MCL1) was conducted. After the selection of OS cell lines, the detection of cell advancement was applied. Series of experiments were conducted to verify the interaction of LINC00641, miR-320d and MCL1. Xenografted tumor model in vivo was utilized to determine the function of LINC00641. The data displayed, LINC00641 was prominently elevated in OS tissues and cells, especially in DDP-resistant tumors and cell lines. Knock-down LINC00641 was able to attenuate progression of DDP-resistant OS cells thus dampening their drug resistance toward DDP. Moreover, knock-downing LINC00641 gene was also able to manifest antagonism toward DDP-resistance in vivo. On the grounds of bioinformatics prediction, a direct binding of LINC00641 with miR-320d existed, whose target was MCL1. Meanwhile, LINC00641 modulated MCL1 via targeting miR-320d. Additionally, repressive LINC00641 blocked MCL1 via emulative interaction with miR-320d, thus expediting DDP-sensitivity of OS cells. All in all, it is found that LINC00641 is available to escalate drug resistance of DDP-resistant OS cells via mediation of miR-320d/MCL1 axis.


Assuntos
Neoplasias Ósseas , Leucemia , MicroRNAs , Osteossarcoma , RNA Longo não Codificante , Apoptose , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , MicroRNAs/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Células Mieloides/metabolismo , Células Mieloides/patologia , Osteossarcoma/tratamento farmacológico , Osteossarcoma/genética , Osteossarcoma/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
7.
Bioengineered ; 13(3): 7351-7366, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35264070

RESUMO

Osteosarcoma is a common bone malignancy in children and adolescents. Chemotherapeutic drug resistance is the major factor impacting the surgical outcome and prognosis of patients with osteosarcoma. This investigation assessed the role and mechanism of circular RNA_ANKIB1 in the development of osteosarcoma. The circular RNA (circ) _ANKIB1, microRNA (miR)-26b-5p, enhancer of zeste homolog 2 (EZH2) expression in OS samples was investigated through RT-qPCR. The EZH2, multidrug resistance protein 1 (MRP1), P-gp, and lipoprotein receptor-related protein (LRP) protein expressions were analyzed through western blot. The association between circ_ANKIB1 and the occurrence of clinic-pathological features in OS patients was assessed; the circular features of circ_ANKIB1 were analyzed. The hFOB1.19, KHOS, U2-OS OS cells were used to study the semi-inhibitory concentration IC50 of Doxorubicin (DXR)-resistant cells, clone formation, invasion, and apoptosis. The luciferase assay was used to study the binding of circ-ANKIB1 with miR-26b-5p and the targeting of miR-26b-5p with EZH2. In vivo experiments were performed via subcutaneous tumorigenic experiments. MiR-26b-5p in OS tissues and cells and DXR-resistant OS tissues and cells was silenced while circ_ANKIB1 and EZH2 were elevated. Circ_ANKIB1 silencing elevated miR-26b-5p, repressed EZH2, MRP1, P-gp, LRP, IC50, and elevated OS advancement. Circ_ANKIB1 bind miR-26b-5p. Reduced miR-26b-5p revered the influence of silencing circ_ANKIB1 on DXR resistant OS cells. MiR-26b-5p targeted EZH2, and EZH2 elevation reversed the impact of increasing miR-26b-5p on DXR resistant cells. Circ_ANKIB1 silencing suppressed DXR-resistant OS cells in vivo. In conclusion, Circ_ANKIB1 binds miR-26b-5p and modulates EZH2 to accelerate the chemo-resistance of osteosarcoma.


Assuntos
Neoplasias Ósseas , MicroRNAs , Osteossarcoma , Adolescente , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Criança , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Humanos , MicroRNAs/metabolismo , Osteossarcoma/metabolismo , RNA Circular/genética
8.
Nat Commun ; 13(1): 360, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35042897

RESUMO

Human 53BP1 is primarily known as a key player in regulating DNA double strand break (DSB) repair choice; however, its involvement in other biological process is less well understood. Here, we report a previously uncharacterized function of 53BP1 at heterochromatin, where it undergoes liquid-liquid phase separation (LLPS) with the heterochromatin protein HP1α in a mutually dependent manner. Deletion of 53BP1 results in a reduction in heterochromatin centers and the de-repression of heterochromatic tandem repetitive DNA. We identify domains and residues of 53BP1 required for its LLPS, which overlap with, but are distinct from, those involved in DSB repair. Further, 53BP1 mutants deficient in DSB repair, but proficient in LLPS, rescue heterochromatin de-repression and protect cells from stress-induced DNA damage and senescence. Our study suggests that in addition to DSB repair modulation, 53BP1 contributes to the maintenance of heterochromatin integrity and genome stability through LLPS.


Assuntos
Heterocromatina/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo , Animais , Linhagem Celular , Núcleo Celular/metabolismo , Homólogo 5 da Proteína Cromobox/metabolismo , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Camundongos Knockout , Mutação/genética , Domínios Proteicos , Estresse Fisiológico , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/química
9.
Bioorg Med Chem ; 54: 116589, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34971877

RESUMO

Recently, we demonstrated potential anti-inflammatory effects of sorbicillinoids isolated from marine fungi. Here, we report the synthesis of a series of new sorbicillinoid analogues and assessed their anti-inflammatory activities. Our results reveal that side chain substitution with (E)-2-butenoyl, (E)-3-(4-fluorophenyl)-2-propenoyl, and (E)-3-(3,4,5-trimethoxyphenyl)-2-propenoyl significantly enhanced the inhibitory effects of the derivatives on nitric oxide (NO) production and inducible NO synthesis (iNOS) expression stimulated by lipopolysaccharides (LPS) in mouse macrophage. Further chemical derivatization shows that the monomethylresorcinol skeleton worked better than the dimethylresorcinol skeleton in inhibiting LPS-induced inflammatory response in cultured cells. Among the 29 synthesized sorbicillinoid analogues, compounds 4b and 12b exhibited the strongest anti-inflammatory activities, holding the promise of being developed into lead compounds that can be explored as potent anti-inflammation agents.


Assuntos
Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Animais , Anti-Inflamatórios não Esteroides , Produtos Biológicos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cicloexanonas , Relação Dose-Resposta a Droga , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Estrutura Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Relação Estrutura-Atividade
10.
Bioorg Med Chem ; 54: 116581, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34968813

RESUMO

In order to study the structure-activity relationship (SAR) of C21-steroidal glycosides toward human cancer cell lines and explore more potential anticancer agents, a series of 3ß-O-neoglycosides of caudatin and its analogues were synthesized. The results revealed that most of peracetylated 3ß-O-monoglycosides demonstrated moderate to significant antiproliferative activities against four human cancer cell lines (MCF-7, HCT-116, HeLa, and HepG2). Among them, 3ß-O-(2,3,4-tri-O-acetyl-ß-L-glucopyranosyl)-caudatin (2k) exhibited the highest antiproliferative activity aganist HepG2 cells with an IC50 value of 3.11 µM. Mechanical studies showed that compound 2k induced both apoptosis and cell cycle arrest at S phase in a dose dependent manner. Overall, these present findings suggested that glycosylation is a promising scaffold to improve anticancer activity for naturally occurring C21-steroidal aglycones, and compound 2k represents a potential anticancer agent deserved further investigation.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas
11.
Chem Biodivers ; 18(7): e2100229, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34085751

RESUMO

Marine derived fungus has gained increasing ground in the discovery of novel lead compounds with potent biological activities including anti-inflammation. Here, we first report the characterization of one new sorbicillinoid (1) and fourteen known compounds (2-15) from the ethyl acetate (AcOEt) extract of a cultured mangrove derived fungus Penicillium sp. DM815 by UV, IR, HR ESI-Q-TOF MS, and NMR spectra. We then evaluated the anti-inflammatory effects of eleven sorbicillinoids (1-11) using cultured macrophage RAW264.7 cells. The results show that compound 9, and to a lesser degree compound 5, significantly inhibited the Gram-negative bacteria lipopolysaccharide (LPS)-induced upregulation of the inducible nitric oxide synthase (iNOS). Consistently, compounds 5 and 9 significantly reduced the level of nitric oxide (NO), the product of iNOS, induced by LPS. We further show that these two compounds dose-dependently inhibited LPS-triggered iNOS expression and NO production, but had no effect on proliferation of RAW264.7 cells in the presence of LPS. In conclusion, our study identifies novel and known sorbicillinoids as potent anti-inflammatory agents, holding the promise of developing novel anti-inflammation treatment in the future.


Assuntos
Anti-Inflamatórios/farmacologia , Penicillium/química , Rhizophoraceae/microbiologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Células RAW 264.7 , Staphylococcus aureus/efeitos dos fármacos
12.
Biochem Pharmacol ; 190: 114622, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34043967

RESUMO

Lung cancer is the leading cause of cancer deaths in the world. Non-small cell lung cancer (NSCLC), with poor prognosis and resistance to chemoradiotherapy, is the most common histological type of lung cancer. Therefore, it is necessary to develop new and more effective treatment strategy for NSCLC. Nur77, an orphan member of the nuclear receptor superfamily, induces apoptosis in cancer cells including NSCLC cells, by high expression and translocation to mitochondria. Small molecules trigger expression and mitochondrial localization of Nur77 may be an ideal anti-cancer drug candidate. Here, we report malayoside, a cardiac glycoside in the extract of Antiaris toxicaria Lesch., had different sensitivities to NSCLC cells. Malayoside induced apoptosis in NCI-H460 cells. Meanwhile, malayoside induced Nur77 expression and mitochondrial localization, and its induction of apoptosis was Nur77-dependent. To investigate the molecular mechanism of malayoside inducing Nur77 and apoptosis, we found that malayoside activated MAPK signaling pathway, including both ERK and p38 phosphorylation. The suppression of MAPK signaling activation inhibited the expression of Nur77 and apoptosis induced by malayoside. Our studies in nude mice showed that malayside potently inhibited the growth of tumor cells in vivo. Furthermore, the anti-cancer effect of malayosidwas in vivo was also related to the elevated expression of Nur77, p-ERK, and p-p38 proteins. Our results suggest that malayoside possesses an anti-NSCLC activity in vitro and in vivo mainly via activation of MAPK-Nur77 signaling pathway, indicating that malayoside is a promising chemotherapeutic candidate for NSCLC.


Assuntos
Antiaris/química , Apoptose/efeitos dos fármacos , Glicosídeos Cardíacos/farmacologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Animais , Carcinoma Pulmonar de Células não Pequenas , Glicosídeos Cardíacos/química , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Nus , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Fitoterapia , Transporte Proteico/efeitos dos fármacos
13.
J Mol Histol ; 52(2): 279-288, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33532936

RESUMO

MicroRNA-27a (miR-27a) modulates osteogenic differentiation (OD); however, the mechanism by which it influences osteoclastic activity in the glucocorticoid (GC)-elicited osteoporotic bone is still unclear. Bone marrow was obtained from the proximal femur of patients (n = 3) with a femoral neck fracture and those (n = 3) with steroid-related osteonecrosis of the femoral head (ONFH). GC was applied to an established ONFH cell model from human bone marrow mesenchymal stem cells (hBMSCs). The miR-27a expression profiles were found to be downregulated in ONFH samples and GC-induced hBMSCs using microarray analysis and real-time quantitative polymerase chain reaction, whereas the OD capacity of hBMSCs was significantly reduced in the GC group compared with the control group. Subsequent transfection of an miR-27a mimic in hBMSCs revealed that the OD capacity of cells was remarkably strengthened in the GC group compared with the miR-control group. Bioinformatics software (TargetScan) predicted that phosphoinositide 3-kinase (PI3K) might be a potential miR-27a target, which was indicated by dual-luciferase reporter assay. Compared with the control group, the GC group exhibited a significantly downregulated protein expression level of PI3K and its downstream protein kinase B (Akt) and mammalian target of rapamycin (mTOR) expression. Furthermore, administration of 10 µM 740 Y-P, a cell-permeable phosphopeptide activator of PI3K, to hBMSCs increased the expression of Akt and mTOR. Treatment with 740 Y-P reversed the effect of miR-27a on OD in hBMSCs. In conclusion, miR-27a is thought to relieve ONFH and the OD repression in GC-induced hBMSCs by targeting the PI3K/Akt/mTOR pathway.


Assuntos
Glucocorticoides/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células Cultivadas , Humanos , MicroRNAs/genética , Fosfatidilinositol 3-Quinases/genética
14.
Fitoterapia ; 149: 104833, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33460724

RESUMO

Naturally occurring C21-steroidal aglycones from Cynanchum exhibit significant antitumor effects. To expand the chemical diversity and get large scale C21-steroidal aglycones, the extracts of the roots of Cynanchum otophyllum were treated with 5% HCl in aqueous and the resulting hydrolysate was investigated. Nine new C21-steroidal aglycones (1-9) namely cynotogenins A-I, along with seventeen known analogous (10-26), were isolated from the hydrolysate. The structures of compounds 1-9 were elucidated by spectroscopic analysis (IR, HR-ESI-MS, 1D and 2D NMR) and comparison of observed spectroscopic data with those of reported in the literature. Aglycones 2-5 with rare cis-cinnamoyl group as well as 8 and 9 with 5ß,6ß-epoxy group were found from the genus of Cynanchum for the first time. The cytotoxicities of compounds 1-26 toward human cancer HeLa, H1299, HepG2, and MCF-7 cells were evaluated and preliminary structure-activity relationship (SAR) was discussed. Moreover, compound 20 inhibits HepG2 cell apoptosis and induces of G0/G1 phase arrest in a dose dependent manner.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Cynanchum/química , Esteroides/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , China , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Raízes de Plantas/química , Esteroides/isolamento & purificação , Relação Estrutura-Atividade
15.
Mar Drugs ; 18(11)2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33233743

RESUMO

Deep-sea fungi have become a new arsenal for the discovery of leading compounds. Here five new ophiobolins 1-5, together with six known analogues 6-11, obtained from a deep-sea derived fungus WHU0154. Their structures were determined by analyses of IR, HR-ESI-MS, and NMR spectra, along with experimental and calculated electronic circular dichroism (ECD) analysis. Pharmacological studies showed that compounds 4 and 6 exhibited obvious inhibitory effects on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in murine macrophage RAW264.7 cells. Mechanical study revealed that compound 6 could inhibit the inducible nitric oxide synthase (iNOS) level in LPS-stimulated RAW264.7 cells. In addition, compounds 6, 9, and 10 could significantly inhibit the expression of cyclooxygenase 2 (COX 2) in LPS-induced RAW264.7 cells. Preliminary structure-activity relationship (SAR) analyses revealed that the aldehyde group at C-21 and the α, ß-unsaturated ketone functionality at A ring in ophiobolins were vital for their anti-inflammatory effects. Together, the results demonstrated that ophiobolins, especially for compound 6, exhibited strong anti-inflammatory effects and shed light on the discovery of ophiobolins as new anti-inflammatory agents.


Assuntos
Anti-Inflamatórios/farmacologia , Aspergillus/metabolismo , Macrófagos/efeitos dos fármacos , Sesterterpenos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Ciclo-Oxigenase 2/metabolismo , Sedimentos Geológicos/microbiologia , Macrófagos/metabolismo , Camundongos , Estrutura Molecular , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Metabolismo Secundário , Sesterterpenos/isolamento & purificação , Relação Estrutura-Atividade
16.
Biochem Pharmacol ; 182: 114226, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32976831

RESUMO

Successful drug repurposing relies on the understanding of molecular mechanisms of the target compound. Cardiac glycosides have demonstrated potent anticancer activities; however, the pharmacological mechanisms underlying their anticancer effects remained elusive, which has restricted their further development in cancer treatment. A bottleneck is the lack of comprehensive understanding about genes and signaling pathways that are altered at the early stage of drug treatment, which is key to understand how they inhibit cancer. To address this issue, we first investigated the anticancer effects of a panel of 68 naturally isolated cardiac glycosides. Our results illustrate critical structure activity relationship of these compounds on cancer cell survival. We confirmed the anticancer effect of cardiac glycoside in mouse tumor xenografts. Through RNA sequencing, quantitative PCR and immunoblotting, we show that cardiac glycoside first activated autophagy and then induced apoptosis. Further activating autophagy by rapamycin or inhibiting apoptosis by caspase inhibitor mitigated cardiac glycoside-induced cell death, whereas inhibiting autophagy by RNA interference-mediated depletion of critical autophagy genes enhanced cell death. While depletion of Na/K-ATPase, the protein target of cardiac glycosides, by RNA interference inhibited both autophagy activation and apoptosis induction by cardiac glycoside, expression of human, but not rodent Na/K-ATPase, increased cell sensitivity to cardiac glycoside. In conclusion, our analyses reveal sequential activation of autophagy and apoptosis during early stages of cardiac glycoside treatment and indicate the importance of Na/K-ATPase in their anticancer effects.


Assuntos
Antineoplásicos/uso terapêutico , Glicosídeos Cardíacos/uso terapêutico , Neoplasias/enzimologia , ATPase Trocadora de Sódio-Potássio/biossíntese , Células A549 , Animais , Antineoplásicos/farmacologia , Glicosídeos Cardíacos/farmacologia , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Indução Enzimática/efeitos dos fármacos , Indução Enzimática/fisiologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
17.
Cell Biol Int ; 44(12): 2532-2540, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32869899

RESUMO

Osteogenic differentiation (OD) of bone marrow mesenchymal stem cells (BMSCs) is critically important for mitigation of osteoporosis. Glucocorticoids (GCs) are extensively used for treating chronic inflammation, although long-term exposure to GCs is capable of triggering osteoporosis. microRNAs (miRNAs) have been reported to play a critical role in bone diseases. In the present study, we treated BMSCs with dexamethasone (DEX) during OD to stimulate GC-mediated osteoporosis. Microarray and quantitative polymerase chain reaction (Q-PCR) assays demonstrated that miR-199a was upregulated during OD of BMSCs, while DEX treatment caused a significant reduction in miR-199a. Alkaline phosphatase (ALP) activity, Alizarin red (AR) staining, and Q-PCR were applied to assess the role of miRNA-199a overexpression in DEX-triggered OD inhibition. miR-199a was able to rescue OD and ALP activity, which were inhibited by DEX. Additionally, we observed that ALP, BMP2, COL1A1, and Runx2 were increased after transfection of miRNA-199a mimics. Furthermore, we confirmed that miRNA-199a facilitates OD of BMSCs through direct inhibition of Klotho protein and messenger RNA expression affecting the downstream fibroblast growth factor receptor 1/extracellular-signal-regulated kinase and Janus kinase 1/signal transducer and activator of transcription 1 pathways. This study indicates that miR-199a plays a critical role in preventing GC-mediated osteoblast differentiation and may function as a promising miRNA biomarker for osteoporosis.


Assuntos
Glucuronidase/metabolismo , MicroRNAs/genética , Osteogênese/genética , Animais , Células da Medula Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Dexametasona/efeitos adversos , Dexametasona/farmacologia , Feminino , Glucocorticoides/metabolismo , Glucocorticoides/farmacologia , Proteínas Klotho , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/metabolismo , Osteoblastos/metabolismo , Osteogênese/efeitos dos fármacos , Osteoporose/metabolismo , Ratos , Ratos Sprague-Dawley
18.
Cancer Lett ; 493: 80-90, 2020 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-32814087

RESUMO

Kirsten rat sarcoma virus oncogene homolog (KRAS) mutant lung cancer remains a challenge to cure and chemotherapy is the current standard treatment in the clinic. Hence, understanding molecular mechanisms underlying the sensitivity of KRAS mutant lung cancer to chemotherapy could help uncover unique strategies to treat this disease. Here we report a compound library screen and identification of cardiac glycosides as agents that selectively enhance the in vitro and in vivo effects of chemotherapy on KRAS mutant lung cancer. Quantitative mass spectrometry reveals that cardiac glycosides inhibit DNA double strand break (DSB) repair through suppressing the expression of UHRF1, an important DSB repair factor. Inhibition of UHRF1 by cardiac glycosides was mediated by specific suppression of the oncogenic KRAS pathway. Overexpression of UHRF1 rescued DSB repair inhibited by cardiac glycosides and depletion of UHRF1 mitigated cardiac glycoside-enhanced chemotherapeutic drug sensitivity in KRAS mutant lung cancer cells. Our study reveals a targetable dependency on UHRF1-stimulated DSB repair in KRAS mutant lung cancer in response to chemotherapy.


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Glicosídeos Cardíacos/administração & dosagem , Reparo do DNA/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Ubiquitina-Proteína Ligases/metabolismo , Células A549 , Animais , Glicosídeos Cardíacos/farmacologia , Linhagem Celular Tumoral , Regulação para Baixo , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Tratamento Farmacológico , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Espectrometria de Massas , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Exp Cell Res ; 396(1): 112243, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32835658

RESUMO

It is challenging to rapidly identify immune responses that reflect the state and capability of immune cells due to complex heterogeneity of immune cells and their plasticity to pathogens and modulating molecules. Thus, high-throughput and easy-to-use cell culture and analysis platforms are highly desired for characterizing complex immune responses and elucidating their underlying mechanisms as well. In response to this need, we have developed a micropillar chip and a 384-pillar plate, printed mouse macrophage, RAW 264.7 cell line in alginate on the pillar plate platforms, and established multiplex cell-based assays to rapidly measure cell viability, expression of cell surface markers, and secretion of cytokines upon stimulation with model compound, lipopolysaccharide (LPS), as well as synthetic N-glycan polymers that mimic native glycoconjugates and could bind to lectin receptors on RAW 264.7 cells. Interestingly, changes in RAW 264.7 cell viability, expression levels of cell surface makers, and release of cytokines measured from the pillar plate platforms in the presence and absence of LPS were well correlated with those obtained from their counterpart, the 96-well plate with 2D-cultured macrophages. With this approach, we identified that α2,3-linked N-sialyllactose polymer has significant macrophage modulation activity among the N-glycan polymers tested. Therefore, we successfully demonstrated that our pillar plate platforms with 3D-cultured macrophages can streamline immune cell imaging and analysis in high throughput in response to compound stimulation. We envision that the pillar plate platforms could potentially be used for rapid characterization of immune cell responses and for screening immune cell-modulating molecules.


Assuntos
Técnicas de Cultura de Células , Glicoconjugados/farmacologia , Ensaios de Triagem em Larga Escala , Lactose/análogos & derivados , Alginatos/química , Animais , Biomarcadores/análise , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultura/química , Expressão Gênica , Glicoconjugados/síntese química , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Lactose/síntese química , Lactose/farmacologia , Lipopolissacarídeos/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Camundongos , Polimerização , Ligação Proteica , Células RAW 264.7 , Receptores Mitogênicos/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/imunologia
20.
Front Pharmacol ; 11: 1088, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32765281

RESUMO

[This corrects the article DOI: 10.3389/fphar.2020.00861.].

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