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1.
Mol Carcinog ; 63(2): 314-325, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37937915

RESUMO

Protein kinase B (AKT) plays a pivotal in regulating cell migration, proliferation, apoptosis, and survival, making it a prominent target for anticancer therapy. While the kinase activity of AKT has been extensively explored, its dephosphorylation have largely remained uncharted. Herein, we aimed to unravel the molecular mechanisms governing AKT dephosphorylation, with a specific emphasis on dual-specificity phosphatases DUSP22. Our investigation sought to shed light on the potential of DUSP22 as a potential therapeutic target for non-small cell lung cancer (NSCLC). To determine the expression level of DUSP22 in NSCLC cell lines, the gene expression profiling interactive analysis (GEPIA) and Oncomine database were searched. Additionally, the effect of DUSP22 on patient survival was analyzed with Kaplan-Meier database. Antitumor effects of DUSP22 were tested in A549 and H1299 cell lines. Experiments are based on: (1) cell viability determined by the cell counting kit-8 assay and colony-formation assay; (2) cell migratory ability assessed through the scratch assay and the transwell migration assay; (3) the mechanism behind the antitumor effects of DUSP22 dissected with co-immunoprecipitation (Co-IP) and in vitro kinase assays. Our study revealed a significant downregulation of DUSP22 in both NSCLC cell lines and tissues. Meanwhile, survival rate analysis results demonstrated that reduced DUSP22 expression was correlated with poorer overall survival in lung cancer patients. Moreover, DUSP22 exhibited an inhibitory effect on the cell viability and migratory capacity of A549 and H1299 cells. This inhibition was accompanied by the decrease in the phosphorylation of AKT and p38. Mechanistically, the phosphatase domain of DUSP22 interacted with AKT, resulting in the inhibition of AKT phosphorylation. This inhibitory effect was contingent upon the phosphatase activity of DUSP22. These findings provide compelling evidence that DUSP22 directly interacted with AKT, leading to the dephosphorylation of AKT at S473 and T308 residues, ultimately curbing the proliferation and migration of lung cancer cells. Additionally, our results also highlight a preclinical rationale for utilizing DUSP22 as a prognostic marker in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Fosfatases de Especificidade Dupla/genética , Fosfatases de Especificidade Dupla/metabolismo , Neoplasias Pulmonares/patologia , Fosfatases da Proteína Quinase Ativada por Mitógeno/genética , Fosfatases da Proteína Quinase Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
2.
Bioresour Technol ; 377: 128935, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36958683

RESUMO

This study aimed to elucidate the multiple strategies employed by anaerobes during granulation in a laboratory upflow anaerobic sludge blanket reactor, based on microbial succession and interactions. The anaerobic granulation process featured staged dominance of microbial genera, corresponding well with the environmental traits. Across the stages (selection, seeding, expansion, and maturation), chemotaxis attraction of nitrogen and/or carbon sources and flagellar motion were the primary strategy of microbial assembly. The second messengers - cyclic adenosine and guanosine monophosphates - partially regulated the agglomeration of filamentous Euryachaeota and Chloroflexi as the inner cores, while quorum sensing mediated the expansion of granules prior to maturation. Antagonism or competition governed the interactions within the phylogenetic molecular ecological network during sludge granulation, which were largely driven by the low-abundance (<1%) taxa. These new insights suggest that better engineering solutions to enhance chemotaxis attraction and species selection could achieve more efficient anaerobic granular sludge processes.


Assuntos
Reatores Biológicos , Esgotos , Anaerobiose , Filogenia , Bactérias Anaeróbias
3.
Sci Rep ; 12(1): 14303, 2022 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-35995961

RESUMO

Many sediment attributes have been proposed as proxies for determining salinity conditions under which sediment is deposited, and six attributes (Sr/Ba-HAc, Sr/Ba-NH4Ac, δ13Corg, C/N, and the relative abundances and concentrations of dinoflagellate cysts) are compared here. In this paper, sediment attributes from the Fraser River Delta, Canada and surrounding coastal areas are compared by depositional position along the fluvial-to-marine transition, by salinity, and by sedimentological characteristics. Along the fluvial-to-marine transition, most attributes exhibit distinct trends between parts of the river that experience sustained marine water (saltwater) influence over seasonal and tidal timeframes, and parts that experience only freshwater or periodic saltwater influence. No attributes are reliable indicators of depositional position where saltwater incursion is short lived or where water is fresh. Where marine influence is sustained, Sr/Ba-HAc and Sr/Ba-NH4Ac are the most reliable positional indicators along the fluvial-to-marine transition. When compared strictly to salinity, Sr/Ba-HAc, Sr/Ba-NH4Ac, and δ13Corg all correlate predictably except in delta front and prodelta settings. Our data show that all six sediment attributes are heavily impacted by river-derived sedimentation, and it is not appropriate to compare values from strongly river-influenced settings (e.g., deltas) with those from weakly river-influenced settings (e.g., bays and estuaries).


Assuntos
Rios , Salinidade , Canadá , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Água
4.
FASEB J ; 35(10): e21923, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34551143

RESUMO

Our recent studies have shown that haspin, a protein kinase imperative for mitosis, is engaged in the interphase progression of HeLa and U2OS cancer cells. In this investigation, we employed the Fucci reporter system and time-lapse imaging to examine the impact of haspin gene silencing on cell cycle progressions at a single-cell level. We found that the loss of haspin induced multiple cell cycle defects. Specifically, the S/G2 duration was greatly prolonged by haspin gene depletion or inhibition in synchronous HeLa cells. Haspin gene depletion in asynchronous HeLa and U2OS cells led to a similarly protracted S/G2 phase, followed by mitotic cell death or postmitotic G1 arrest. In addition, haspin deficiency resulted in robust induction of the p21CIP1/WAF1 checkpoint protein, a target of the p53 activation. Also, co-depleting haspin with either p21 or p53 could rescue U2OS cells from postmitotic G1 arrest and partially restore their proliferation. These results substantiate the haspin's capacity to regulate interphase and mitotic progression, offering a broader antiproliferative potential of haspin loss in cancer cells.


Assuntos
Ciclo Celular , Proliferação de Células , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Neoplasias/patologia , Proteínas Serina-Treonina Quinases/deficiência , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Corantes Fluorescentes , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Fase G2/efeitos dos fármacos , Humanos , Interfase/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mitose/efeitos dos fármacos , Neoplasias/genética , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Fase S/efeitos dos fármacos , Tubercidina/análogos & derivados , Tubercidina/farmacologia , Proteína Supressora de Tumor p53/genética , Ubiquitinação , Regulação para Cima/efeitos dos fármacos
5.
J Cell Physiol ; 235(5): 4508-4519, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31625162

RESUMO

Haspin (Haploid Germ Cell-Specific Nuclear Protein Kinase) is a serine/threonine kinase pertinent to normal mitosis progression and mitotic phosphorylation of histone H3 at threonine 3 in mammalian cells. Different classes of small molecule inhibitors of haspin have been developed and utilized to investigate its mitotic functions. We report herein that applying haspin inhibitor CHR-6494 or 5-ITu at the G1/S boundary could delay mitotic entry in synchronized HeLa and U2OS cells, respectively, following an extended G2 or the S phase. Moreover, late application of haspin inhibitors at S/G2 boundary is sufficient to delay mitotic onset in both cell lines, thereby, indicating a direct effect of haspin on G2/M transition. A prolonged interphase duration is also observed with knockdown of haspin expression in synchronized and asynchronous cells. These results suggest that haspin can regulate cell cycle progression at multiple stages at both interphase and mitosis.


Assuntos
Ciclo Celular/efeitos dos fármacos , Ciclo Celular/fisiologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Indazóis/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Piridazinas/farmacologia , Tubercidina/análogos & derivados , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mitose , Proteínas Serina-Treonina Quinases/genética , Tubercidina/farmacologia
6.
Int J Syst Evol Microbiol ; 69(11): 3318-3325, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30422104

RESUMO

Two isolates of heterotrophic, facultatively anaerobic, marine bacteria, designated DM1 and DM2T, were recovered from a lagoon sediment sample of Dongsha Island, Taiwan. Cells were Gram-reaction-negative rods. Nearly all of the cells were non-motile and non-flagellated during the late exponential to early stationary phase of growth, while a few of the cells exhibited motility with monotrichous flagellation. The two isolates required NaCl for growth and grew optimally at about 30 °C, 2-3 % NaCl and pH 7-8. They grew aerobically and could achieve anaerobic growth by fermenting d-glucose or other carbohydrates with production of acids and the gases, including CO2 and H2. Ubiquinone Q-8 was the only respiratory quinone. Cellular fatty acids were predominated by C16 : 0, C18 : 1ω7c and C16 : 1ω7c. The major polar lipid was phosphatidylethanolamine. Strains DM1 and DM2T had DNA G+C contents of 52.0 and 51.8 mol%, respectively, as determined by HPLC analysis. Phylogenetic analyses based on 16S rRNA gene sequences clearly indicated that the two isolates formed a distinct genus-level lineage in the family Aeromonadaceae of the class Gammaproteobacteria and was an outgroup with respect to a stable supragenic clade comprising species of the genera Oceanimonas, Oceanisphaera and Zobellella. The phylogenetic data and those from chemotaxonomic, physiological and morphological characterizations support the establishment of a novel species and genus inside the family Aeromonadaceae, for which the name Dongshaea marina gen. nov., sp. nov. is proposed. The type strain is DM2T (=BCRC 81069T=JCM 32096T).


Assuntos
Aeromonadaceae/classificação , Sedimentos Geológicos/microbiologia , Glucose/metabolismo , Filogenia , Água do Mar/microbiologia , Aeromonadaceae/isolamento & purificação , Anaerobiose , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fermentação , Gases , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Taiwan , Ubiquinona/química
7.
J Cell Physiol ; 233(12): 9563-9574, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29943823

RESUMO

A diverse array of biological processes are under circadian controls. In mouse skin, ultraviolet ray (UVR)-induced apoptosis and DNA damage responses are time-of-day dependent, which are controlled by core clock proteins. This study investigates the roles of clock proteins in regulating UVB responses in human keratinocytes (HKCs). We found that the messenger RNA expression of brain and muscle ARNT-like 1 (BMAL1) and circadian locomotor output cycles kaput (CLOCK) genes is altered by low doses (5 mJ/cm2 ) of UVB in the immortalized HaCat HKCs cell line. Although depletion of BMAL1 or CLOCK has no effect on the activation of Rad3-related protein kinases-checkpoint kinase 1-p53 mediated DNA damage checkpoints, it leads to suppression of UVB-stimulated apoptotic responses, and downregulation of UVB-elevated expression of DNA damage marker γ-H2AX and cell cycle inhibitor p21. Diminished apoptotic responses are also observed in primary HKCs depleted of BMAL1 or CLOCK after UVB irradiation. While CLOCK depletion shows a suppressive effect on UVB-induced p53 protein accumulation, depletion of either clock gene triggers early keratinocyte differentiation of HKCs at their steady state. These results suggest that UVB-induced apoptosis and DNA damage responses are controlled by clock proteins, but via different mechanisms in the immortalized human adult low calcium temperature and primary HKCs. Given the implication of UVB in photoaging and photocarcinogenesis, mechanistic elucidation of circadian controls on UVB effects in human skin will be critical and beneficial for prevention and treatment of skin cancers and other skin-related diseases.


Assuntos
Fatores de Transcrição ARNTL/metabolismo , Apoptose/efeitos da radiação , Proteínas CLOCK/metabolismo , Dano ao DNA , Queratinócitos/metabolismo , Queratinócitos/efeitos da radiação , Raios Ultravioleta , Fatores de Transcrição ARNTL/genética , Proteínas CLOCK/genética , Diferenciação Celular/efeitos da radiação , Linhagem Celular , Proliferação de Células/genética , Proliferação de Células/efeitos da radiação , Relação Dose-Resposta à Radiação , Regulação da Expressão Gênica , Histonas/metabolismo , Humanos , Queratinócitos/citologia
8.
J Cancer ; 8(15): 2933-2943, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28928884

RESUMO

Background: Melanoma is a heterogeneous malignancy that presents an immense challenge in therapeutic development. Recent approaches targeting the oncogenic MAP kinase pathways have shown tremendous improvement in the overall survival of patients with advanced melanoma. However, there is still an urgent need for identification of new strategies to overcome drug resistances and to improve therapeutic efficacy. Haspin (Haploid Germ Cell-Specific Nuclear Protein Kinase) belongs to a selected group of mitotic kinases and is required for normal mitosis progression. In contrast to inhibitors of other mitotic kinases, anti-tumor potential of haspin inhibitors has not been well explored. Herein, we aim to examine effects of CHR-6494, a small molecule inhibitor of haspin, in melanoma cells. Methods: Anti-tumor activities of the haspin inhibitor CHR-6494 were tested in a number of melanoma cell lines either as a single agent or in combination with the MEK inhibitor Trametinib (GSK1120212). Experiments are based on: 1) Cell viability determined by the crystal violet staining assay; 2) apoptotic responses measured by the caspase 3/7 activity assay and western blot analysis for the level of cleaved PARP (Poly ADP-Ribose Polymerase); 3) cell cycle analysis conducted using flow cytometry; and 4) cell migratory ability assessed by the scratch assay and the transwell migration assay. Results: We have found that CHR-6494 alone elicits a dose dependent inhibitory effect on the viability of several melanoma cell lines. This growth inhibition is accompanied by an increase in apoptotic responses. More importantly, CHR-6494 appears to synergize with the MEK inhibitor Trametinib in suppressing cell growth and enhancing apoptosis in both wild type and BRAFV600E mutant melanoma cell lines. Administering of these two small molecules as a combination is also capable of suppressing cell migration to a greater extent than the individual agent. Conclusion: These results suggest that haspin can be considered as a viable anti-melanoma target, and that concomitant inhibition of haspin and MEK activities with small molecules could represent a novel therapeutic strategy with improved efficacy for treatment of melanoma.

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