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1.
J Transl Med ; 22(1): 769, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143573

RESUMO

BACKGROUND: Although immune checkpoint inhibitors (ICIs) have revolutionized the landscape of cancer treatment, only a minority of colorectal cancer (CRC) patients respond to them. Enhancing tumor immunogenicity by increasing major histocompatibility complex I (MHC-I) surface expression is a promising strategy to boost the antitumor efficacy of ICIs. METHODS: Dual luciferase reporter assays were performed to find drug candidates that can increase MHC-I expression. The effect of nilotinib on MHC-I expression was verified by dual luciferase reporter assays, qRT-PCR, flow cytometry and western blotting. The biological functions of nilotinib were evaluated through a series of in vitro and in vivo experiments. Using RNA-seq analysis, immunofluorescence assays, western blotting, flow cytometry, rescue experiments and microarray chip assays, the underlying molecular mechanisms were investigated. RESULTS: Nilotinib induces MHC-I expression in CRC cells, enhances CD8+ T-cell cytotoxicity and subsequently enhances the antitumor effects of anti-PDL1 in both microsatellite instability and microsatellite stable models. Mechanistically, nilotinib promotes MHC-I mRNA expression via the cGAS-STING-NF-κB pathway and reduces MHC-I degradation by suppressing PCSK9 expression in CRC cells. PCSK9 may serve as a potential therapeutic target for CRC, with nilotinib potentially targeting PCSK9 to exert anti-CRC effects. CONCLUSION: This study reveals a previously unknown role of nilotinib in antitumor immunity by inducing MHC-I expression in CRC cells. Our findings suggest that combining nilotinib with anti-PDL1 therapy may be an effective strategy for the treatment of CRC.


Assuntos
Neoplasias Colorretais , Pirimidinas , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/metabolismo , Humanos , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe I/genética , Camundongos , Instabilidade de Microssatélites/efeitos dos fármacos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Transdução de Sinais/efeitos dos fármacos
2.
Biochemistry ; 61(7): 575-582, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35285625

RESUMO

Human phosphoribosylaminoimidazole carboxylase phosphoribosylaminoimdiazole succinocarboxamide synthetase (PAICS) is a dual activity enzyme catalyzing two consecutive reactions in de novo purine nucleotide synthesis. Crystallographic structures of recombinant human PAICS suggested the channeling of 4-carboxy-5-aminoimidazole-1-ribose-5'-phosphate (CAIR) between two active sites of PAICS, while a prior work of an avian PAICS suggested otherwise. Here, we present time-course mass spectrometric data supporting the channeling of CAIR between domains of recombinant human PAICS. Time-course mass spectral analysis showed that CAIR added to the bulk solution (CAIRbulk) is decarboxylated and re-carboxylated before the accumulation of succinyl-5-aminoimidazole-4-carboxamide-1-ribose-5'-phosphate (SAICAR). An experiment with 13C-bicarbonate showed that SAICAR production was proportional to re-carboxylated CAIR instead of total CAIR or CAIRbulk. This result indicates that the SAICAR synthase domain selectively uses enzyme-made CAIR over CAIRbulk, which is consistent with the channeling model. This channeling between PAICS domains may be a part of a larger channeling process in de novo purine nucleotide synthesis.


Assuntos
Bicarbonatos , Carboxiliases , Peptídeo Sintases , Carboxiliases/química , Domínio Catalítico , Humanos , Enzimas Multifuncionais/química , Peptídeo Sintases/química
3.
Mol Biol Rep ; 49(6): 4281-4292, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35262820

RESUMO

BACKGROUND: The emergence of nonresponse or resistance to traditional chemotherapeutic agents is one of the main challenges of colorectal cancer (CRC) therapies. Thus, novel therapeutic drugs that can improve the clinical outcomes of CRC patients are urgently needed. The purpose of this study was to investigate the effects and mechanisms of pyrimethamine in CRC. METHODS AND RESULTS: In this study, we assessed the role of pyrimethamine on CRC cell growth by cell counting kit-8 and colony formation assays. Cell cycle distribution and cellular senescence were determined by flow cytometry and senescence-associated ß-galactosidase staining respectively. RNA-seq analysis and western blotting were used to investigate the potential pathways of pyrimethamine in CRC development. Moreover, animal experiments were performed to evaluate the effect of pyrimethamine in vivo. Our results demonstrated that pyrimethamine could inhibit cell growth by inducing S phase arrest followed by cellular senescence in CRC cells, and the p38MAPK-p53 axis was probably involved in that effect. In addition, pyrimethamine could also boost CD8+ T-cell mediated cytotoxicity and exert antitumor activity in vivo. CONCLUSION: These results indicated that pyrimethamine may be a promising candidate agent for CRC treatment.


Assuntos
Neoplasias Colorretais , Pirimetamina , Animais , Apoptose , Linfócitos T CD8-Positivos , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Senescência Celular , Neoplasias Colorretais/metabolismo , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Linfócitos T/metabolismo
4.
Biol Pharm Bull ; 45(9): 1238-1245, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36047191

RESUMO

Despite advances in colorectal cancer (CRC) treatment, most advanced CRC patients who experience disease progression after chemotherapy, targeted therapy, and immunotherapy face a situation in which there is no available medicine. Thus, new therapeutic drugs for CRC are urgently needed. Studies have shown that cholesteryl ester transfer protein (CETP) has a vital role in tumor development and is a possible target for CRC therapy. We found that Evacetrapib, a CETP inhibitor, suppressed CRC cell growth by inhibiting the Wnt/ß-catenin signaling pathway and activating the c-Jun NH2-terminal kinase (JNK) signaling pathway in CRC. Therefore, Evacetrapib displays an anti-cancer effect and is a possible option for treating CRC.


Assuntos
Neoplasias Colorretais , Via de Sinalização Wnt , Benzodiazepinas , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Sistema de Sinalização das MAP Quinases , beta Catenina/metabolismo
5.
J Clin Lab Anal ; 34(3): e23086, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31713278

RESUMO

BACKGROUND: This study aimed to investigate circular RNA-mitochondrial tRNA translation optimization 1 (circ-MTO1) expression in tumor tissue and its correlation with clinical characteristics and survival profiles, as well as its effect on cancer cell functions in prostate cancer. METHODS: A total of 298 primary prostate cancer patients were included. Reverse transcription-quantitative polymerase chain reaction was conducted to evaluate circ-MTO1 expression in tumor tissue and paired adjacent tissue. Disease-free survival (DFS) and overall survival (OS) were recorded. In in vitro experiment, prostate cancer cells were transfected with circ-MTO1 over-expression and negative-control over-expression plasmids. Then cell proliferation, cell invasion and miR-630 as well as miR-17-5p expressions in prostate cancer cells were detected. RESULTS: Circular RNA-mitochondrial tRNA translation optimization 1 expression was downregulated in tumor tissue compared with paired adjacent tissue (P < .001) in patients with prostate cancer. Circ-MTO1 high expression in tumor tissue was correlated with decreased pathological T stage (P = .001) as well as lower pathological N stage (P = .020). As for survival profiles, the DFS (P = .006) and OS (P = .018) were both longer in patients who had circ-MTO1 high expression compared with patients who had circ-MTO1 low expression. In addition, circ-MTO1 high expression independently predicted favorable DFS and OS. Besides, further in vitro experiments illustrated that circ-MTO1 inhibited proliferation (P < .05) and invasion (P < .05) as well as downregulated miR-17-5p expression in prostate cancer cells (P < .05). CONCLUSION: Circ-MTO1 correlates with decreased pathological T/N stage and favorable survival profiles, and it also inhibits cell proliferation, invasion as well as miR-17-5p expression in prostate cancer.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , RNA Circular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Intervalo Livre de Doença , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , RNA Circular/genética
6.
Accid Anal Prev ; 205: 107682, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38936321

RESUMO

Street space plays a critical role in pedestrian safety, but the influence of fine-scale street environment features has not been sufficiently understood. To analyze the effect of the street environment at the link level, it is essential to account for the spatial variation of pedestrian exposure across street links, which is challenging due to the lack of detailed pedestrian flow data. To address these issues, this study proposes to extract link-level pedestrian exposure from spatially ubiquitous street view images (SVIs) and investigate the impact of fine-scale street environment on pedestrian crash risks, with a particular focus on pedestrian facilities (e.g., crossing and sidewalk design). Both crash frequency and severity are analyzed at the link level, with the latter incorporating two distinct aggregation metrics: maximum severity and medium severity. Using Hong Kong as a case study, the results show that the link-level pedestrian exposure extracted from SVIs can lead to better model fit than alternative zone-level measurements. Specifically, higher pedestrian exposure is found to increase the total pedestrian crash frequency, while reducing the risk of serious injuries or fatalities, confirming the "safety in numbers" effect for pedestrians. Pedestrian facilities are also shown to influence pedestrian crash frequency and severity in different ways. The presence of crosswalks can increase crash frequency, but denser crosswalk design mitigates this effect. In addition, two-side sidewalks can increase crash frequency, while the absence of sidewalks leads to higher risks of crash severity. These findings highlight the importance of fine-scale street environment and pedestrian facility design for pedestrian safety.


Assuntos
Acidentes de Trânsito , Planejamento Ambiental , Pedestres , Humanos , Acidentes de Trânsito/estatística & dados numéricos , Acidentes de Trânsito/prevenção & controle , Pedestres/estatística & dados numéricos , Hong Kong , Segurança , Caminhada/lesões , Ambiente Construído
7.
Research (Wash D C) ; 7: 0453, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39145116

RESUMO

Flexible epidermal electrodes hold substantial promise in realizing human electrophysiological information collections. Conventional electrodes exhibit certain limitations, including the requirement of skin pretreatment, reliance on external object-assisted fixation, and a propensity of dehydration, which severely hinder their applications in medical diagnosis. To tackle those issues, we developed a hydrogel electrode with both transcutaneous stimulation and neural signal acquisition functions. The electrode consists of a composite conductive layer (CCL) and adhesive conductive hydrogel (ACH). The CCL is designed as a laminated structure with high conductivity and charge storage capacity (CSC). Based on the optimization of Hoffmeister effect, the ACH demonstrates excellent electrical (resistivity of 3.56 Ω·m), mechanical (tensile limit of 1,650%), and adhesion properties (peeling energy of 0.28 J). The utilization of ACH as electrode/skin interface can reduce skin contact impedance and noise interference and enhance the CSC and charge injection capacity of electrodes. As a proof of concept, peripheral nerve conduction studies were performed on human volunteers to evaluate the as-fabricated hydrogel electrodes. Compared with the commercial electrodes, our hydrogel electrodes achieved better signal continuity and lower distortion, higher signal-to-noise ratio (~35 dB), and lower stimulation voltages (up to 27% lower), which can improve the safety and comfort of nerve conduction studies.

8.
Front Microbiol ; 15: 1366021, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577687

RESUMO

4-Hydroxy-2,5-dimethyl-3 (2H)-furanone (HDMF) is widely used in the food industry as a spice and flavoring agent with high market demand. In this study, fructose-1,6-bisphosphate aldolase (FBA) and triose phosphate isomerase (TPI) were overexpressed in Zygosaccharomyces rouxii in the form of single and double genes, respectively, via electroporation. High-yield HDMF-engineered yeast strains were constructed by combining the analysis of gene expression levels obtained by real-time fluorescence quantitative PCR technology and HDMF production measured by HPLC. The results showed that there was a significant positive correlation between the production of HDMF and the expression levels of the FBA and TPI genes in yeast; the expression levels of the FBA and TPI genes were also positively correlated (p < 0.05). Compared with the wild type (WT), the engineered strains F10-D, T17-D, and TF15-A showed marked increases in HDMF production and FBA and TPI gene expression (p < 0.05) and exhibited great genetic stability with no obvious differences in biomass or colony morphology. In addition, the exogenous addition of d-fructose promoted the growth of Z. rouxii. Among the engineered strains, when fermented in YPD media supplemented with d-fructose for 5 days, TF15-A (overexpressing the FBA and TPI genes) generated the highest HDMF production of 13.39 mg/L, which is 1.91 times greater than that of the wild-type strain. The results above indicated that FBA and TPI, which are key enzymes involved in the process of HDMF biosynthesis by Z. rouxii, positively regulate the synthesis of HDMF at the transcriptional level. d-fructose can be used as a precursor for the biosynthesis of HDMF by engineered yeast in industrial production.

9.
Food Sci Nutr ; 12(6): 4435-4442, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38873477

RESUMO

4-Hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF) is a flavor compound widely found in natural products and is used in food as a flavor-enhancing agent. Quinone oxidoreductase (QOR) was verified as a key enzyme to synthesize HDMF in strawberry, while its impact on HDMF production by Zygosaccharomyces rouxii was still unknown. The QOR gene was cloned and overexpressed in Z. rouxii, and its impact on HDMF production by Z. rouxii was then further analyzed. At the same time, it is expected to obtain engineered strains of Z. rouxii with high HDMF production. The results showed that the engineered strains of Z. rouxii exhibit different levels of QOR gene expression and HDMF production; among them, the QOR6 strain exhibiting the highest gene expression level and HDMF production was named as ZrQOR. The HDMF production of the ZrQOR strain was significantly higher than that of wild-type Z. rouxii at 3 and 5 days of culture, with 1.41-fold and 1.08-fold increases, respectively. At 3 days of fermentation, the highest HDMF yield of ZrQOR strain was obtained (2.75 mg/L), 2 days ahead of the reported highest HDMF production by Z. rouxii. At 3, 5, and 7 days, QOR gene expression was 4.8-fold, 3.3-fold, and 5.6-fold higher in the ZrQOR strain than in the wild-type Z. rouxii, respectively. Therefore, overexpression of the QOR gene facilitates HDMF synthesis. The genetic stability of the 0-20 generation ZrQOR strain was stable, and there was no significant difference in colony shape, QOR expression, or HDMF production compared to the wild type. In this study, the genetic engineering Z. rouxii strain was used to improve HDMF production. This research has laid the groundwork for further industrial production of HDMF via microbial synthesis.

10.
Adv Mater ; : e2308831, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37906182

RESUMO

Peripheral neuropathy characterized by rapidly increasing numbers of patients is commonly diagnosed via analyzing electromyography signals obtained from stimulation-recording devices. However, existing commercial electrodes have difficulty in implementing conformal contact with skin and gentle detachment, dramatically impairing stimulation/recording performances. Here, this work develops on-skin patches with polyaspartic acid-modified dopamine/ethyl-based ionic liquid hydrogel (PDEH) as stimulation/recording devices to capture electromyography signals for the diagnosis of peripheral neuropathy. Triggered by a one-step electric field treatment, the hydrogel achieves rapid and wide-range regulation of adhesion and substantially strengthened mechanical performances. Moreover, hydrogel patches assembled with a silver-liquid metal (SLM) layer exhibit superior charge injection and low contact impedance, capable of capturing high-fidelity electromyography. This work further verifies the feasibility of hydrogel devices for accurate diagnoses of peripheral neuropathy in sensory, motor, and mixed nerves. For various body parts, such as fingers, the elderly's loose skin, hairy skin, and children's fragile skin, this work regulates the adhesion of PDEH-SLM devices to establish intimate device/skin interfaces or ensure benign removal. Noticeably, hydrogel patches achieve precise diagnoses of nerve injuries in these clinical cases while providing extra advantages of more effective stimulation/recording performances. These patches offer a promising alternative for the diagnosis and rehabilitation of neuropathy in future.

11.
Front Public Health ; 10: 862598, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35419331

RESUMO

It is difficult to study the intestinal damage induced by space radiation to astronauts directly, and few prediction models exist. However, we can simulate it in patients with pelvic tumor radiotherapy (RT). Radiation-induced intestinal injury (RIII) is common in cancer patients who receieved pelvic and abdominal RT. We dynamically analyzed gut microbiota and metabolites alterations in 17 cervical and endometrial cancer patients after pelvic RT. In patients who later developed grade 2 RIII, dysbiosis of gut microbiota and metabolites were observed. Univariate analysis showed that Erysipelatoclostridium and ptilosteroid A were related to the occurrence of grade 2 RIII. Notably, a strong positive correlation between gut bacteria Erysipelatoclostridium relative abundance and gut metabolite ptilosteroid A expression was found. Furthermore, combinations of Erysipelatoclostridium and ptilosteroid A could provide good diagnostic markers for grade 2 RIII. In conclusion, gut bacteria Erysipelatoclostridium and its related metabolite ptilosteroid A may collaboratively predict RIII, and could be diagnostic biomarkers for RIII and space radiation injury.


Assuntos
Microbioma Gastrointestinal , Lesões por Radiação , Bactérias , Disbiose/microbiologia , Humanos , Pregnanos
13.
Sci Rep ; 7(1): 8154, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28811627

RESUMO

The response of tropical cyclone (TC) destructive potential to global warming is an open issue. A number of previous studies have ignored the effect of TC size change in the context of global warming, which resulted in a significant underestimation of the TC destructive potential. The lack of reliable and consistent historical data on TC size limits the confident estimation of the linkage between the observed trend in TC size and that in sea surface temperature (SST) under the background of global climate warming. A regional atmospheric model is used in the present study to investigate the response of TC size and TC destructive potential to increases in SST. The results show that a large-scale ocean warming can lead to not only TC intensification but also TC expansion. The TC size increase in response to the ocean warming is possibly attributed to the increase in atmospheric convective instability in the TC outer region below the middle troposphere, which facilitates the local development of grid-scale ascending motion, low-level convergence and the acceleration of tangential winds. The numerical results indicate that TCs will become stronger, larger, and unexpectedly more destructive under global warming.

14.
Oncol Lett ; 9(5): 2353-2360, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26137070

RESUMO

Pancreatic cancer is one of the most frequently occurring malignancies worldwide and it is the fourth most common cause of cancer-associated mortality in Western countries. Thalidomide (THD) plays an important role in tumor therapy, as it is able to promote early stage apoptosis and inhibit the process of angiogenesis. The present study evaluated the ability of the combination of THD and gemcitabine (GEM) to inhibit the growth of the pancreatic cancer SW-1990 cell line in vitro and in vivo. Early apoptosis in the SW-1990 cells was detected by the Annexin V/propidium iodide double staining method, the level of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (Bax) were detected by reverse transcription-polymerase chain reaction (RT-PCR) and western blot analysis. In addition, the expression of vascular endothelial growth factor in transplanted tumor tissue was measured by RT-PCR, immunohistochemistry and western blot analysis. Cluster of differentiation 34 positivity was considered to indicate the microvessel density. Subsequent to treatment with THD and GEM alone or in combination, it was found that the expression of Bax was upregulated, while the expression of Bcl-2 was downregulated, and the growth of SW-1990 cells and transplanted tumors in nude mice was evidently inhibited. The administration of THD in combination with GEM may demonstrate a potent antitumor effect that increases with increasing dose. The mechanism behind the antitumor effect may be associated with the inhibition of tumor angiogenesis and induction of the apoptosis pathway.

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