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1.
Cell Death Discov ; 10(1): 373, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39174498

RESUMO

Nuclear regulation has potential in cancer therapy, with the nuclear pore complex (NPC) serving as a critical channel between the nucleus and cytoplasm, playing a role in regulating various biological processes and cancer. DNA methylation, an epigenetic modification mediated by DNA methyltransferases (DNMTs), influences gene expression and cell differentiation, and is crucial for the development and progression of tumor cells. Gliomas are the most common primary brain tumors, with glioblastoma being particularly aggressive, characterized by invasiveness, migration capability, and resistance to conventional treatments, resulting in poor prognosis. Our study revealed that the expression level of NUP37 affects the proliferation and invasion of glioma cells, and that the overexpression of DNMT1 can alleviate the adverse effects caused by NUP37 depletion. These findings suggest that NUP37 promotes the proliferation and invasion of glioma cells through its interaction with DNMT1.

2.
Cell Mol Life Sci ; 81(1): 247, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829550

RESUMO

BACKGROUND: The high degree of intratumoral genomic heterogeneity is a major obstacle for glioblastoma (GBM) tumors, one of the most lethal human malignancies, and is thought to influence conventional therapeutic outcomes negatively. The proneural-to-mesenchymal transition (PMT) of glioma stem cells (GSCs) confers resistance to radiation therapy in glioblastoma patients. POLD4 is associated with cancer progression, while the mechanisms underlying PMT and tumor radiation resistance have remained elusive. METHOD: Expression and prognosis of the POLD family were analyzed in TCGA, the Chinese Glioma Genome Atlas (CGGA) and GEO datasets. Tumorsphere formation and in vitro limiting dilution assay were performed to investigate the effect of UCHL3-POLD4 on GSC self-renewal. Apoptosis, TUNEL, cell cycle phase distribution, modification of the Single Cell Gel Electrophoresis (Comet), γ-H2AX immunofluorescence, and colony formation assays were conducted to evaluate the influence of UCHL3-POLD4 on GSC in ionizing radiation. Coimmunoprecipitation and GST pull-down assays were performed to identify POLD4 protein interactors. In vivo, intracranial xenograft mouse models were used to investigate the molecular effect of UCHL3, POLD4 or TCID on GCS. RESULT: We determined that POLD4 was considerably upregulated in MES-GSCs and was associated with a meagre prognosis. Ubiquitin carboxyl terminal hydrolase L3 (UCHL3), a DUB enzyme in the UCH protease family, is a bona fide deubiquitinase of POLD4 in GSCs. UCHL3 interacted with, depolyubiquitinated, and stabilized POLD4. Both in vitro and in vivo assays indicated that targeted depletion of the UCHL3-POLD4 axis reduced GSC self-renewal and tumorigenic capacity and resistance to IR treatment by impairing homologous recombination (HR) and nonhomologous end joining (NHEJ). Additionally, we proved that the UCHL3 inhibitor TCID induced POLD4 degradation and can significantly enhance the therapeutic effect of IR in a gsc-derived in situ xenograft model. CONCLUSION: These findings reveal a new signaling axis for GSC PMT regulation and highlight UCHL3-POLD4 as a potential therapeutic target in GBM. TCID, targeted for reducing the deubiquitinase activity of UCHL3, exhibited significant synergy against MES GSCs in combination with radiation.


Assuntos
Células-Tronco Neoplásicas , Tolerância a Radiação , Ubiquitina Tiolesterase , Humanos , Ubiquitina Tiolesterase/metabolismo , Ubiquitina Tiolesterase/genética , Tolerância a Radiação/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/efeitos da radiação , Animais , Camundongos , Linhagem Celular Tumoral , Glioma/patologia , Glioma/genética , Glioma/radioterapia , Glioma/metabolismo , Apoptose/genética , Apoptose/efeitos da radiação , Ubiquitinação , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Camundongos Nus , Fenótipo , Regulação Neoplásica da Expressão Gênica , Prognóstico
3.
Opt Express ; 31(16): 25598-25612, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710442

RESUMO

To meet the demand of flexible access for high-precision synchronization frequency, we demonstrate multi-node stable radio frequency (RF) dissemination over a long-distance optical fiber. Stable radio frequency signals can be extracted at any node along the optical fiber, not just at the endpoint. The differential mixing structure (DMS) is employed to avoid the frequency harmonic leakage and enhance the precision. The phase-locked loop (PLL) provides frequency reference for the DMS while improving the signal to noise ratio (SNR) of dissemination signal. We measure the frequency instability of multi-node stable frequency dissemination system (MFDS) at different locations along the 2,000 km optical fiber. The measured short-term instability with average time of 1 s are 1.90 × 10-14 @ 500 km, 2.81 × 10-14 @ 1,000 km, 3.46 × 10-14 @ 1,500 km, and 3.84 × 10-14 @ 2,000 km respectively. The long-term instability with average time of 10,000 s are basically the same at any position of the optical fiber, which is about (6.24 ± 0.05) × 10-17. The resulting instability is sufficient for the propagation of precision active hydrogen masers.

4.
Pathol Res Pract ; 234: 153911, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35489125

RESUMO

BACKGROUND: Pancreatic cancer (PC) is one of the most malignant solid tumors and its 5-year survival rate remains poor. Although immunotherapy has achieved certain therapeutic efficacy in some clinical trials, such treatment still shows low responses and overall remission rate. Therefore, it is urgently necessary to dissect the tumor microenvironment and optimize the immunotherapeutic strategies against this malignancy. METHODS: Using the multi-color immunohistochemistry assay, we investigated the expressions of B7-H3, B7-H4, HHLA2, CD8, and CD68 in 63 cases of PC tissues in a tissue microarray. Moreover, we analyzed immunolocalization features, clinical associations and prognostic values of these molecules. RESULTS: The expressions of B7-H3, B7-H4, and HHLA2 could be detected in cytokeratin staining positive (CK+) cancer epithelial cells, CD68+tumor-associated macrophages (TAMs), and even other cells defined as CK-CD8-CD68-. Higher expression of B7-H3 in tumor cells could predict a better survival of the PC patients. A positive correlation was found between the expressions of B7-H3 and HHLA2 in tumor cells, while there was a negative correlation between the expressions of B7-H4 and HHLA2 in tumor cells. A positive correlation was found between the expressions of B7-H3 and B7-H4 or HHLA2 in CD68+TAMs, but not B7-H4 and HHLA2. Tumor-infiltrating CD8+T cells in combination with CD68+TAMs could serve as an important predictor for the postoperative prognosis of PC patients. Higher expression of B7-H3, or HHLA2 in CD68+TAMs could serve as an important predictor for poorer prognosis of PC patients. Patients with B7-H3lowB7-H4low, B7-H3lowHHLA2low, or B7-H4lowHHLA2low on CD68+TAMs could have a better postoperative prognosis compared with the other sub-populations in the combinational analysis. CONCLUSIONS: Taken together, our study indicated variable expressions and prognostic values of B7-H3, B7-H4, and HHLA2, in human PC tissues, and demonstrated that these co-stimulator molecules expressed by CD68+TAMs could be used as important bio-markers for the prognostic prediction of PC patients. Moreover, these results supported that the evaluation of these markers could be used as essential candidate targets for immunotherapy against PC.


Assuntos
Linfócitos do Interstício Tumoral , Neoplasias Pancreáticas , Biomarcadores Tumorais/metabolismo , Humanos , Imunoglobulinas , Imuno-Histoquímica , Linfócitos do Interstício Tumoral/patologia , Neoplasias Pancreáticas/patologia , Prognóstico , Microambiente Tumoral , Neoplasias Pancreáticas
5.
Front Oncol ; 11: 754834, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660323

RESUMO

Long non-coding RNAs (lncRNAs) play important roles in various biological processes and human diseases, including cancer. In this study, we demonstrated a regulatory relationship between lncRNA GRIK1-AS1 and miR-375/IFIT2 axis in gastric cancer. Our results show a decreased expression of GRIK1-AS1 in gastric cancer tissues compared to adjacent normal gastric tissues. Gastric cell lines also have reduced levels of GRIK1-AS1 compared to gastric epithelial cell line GES-1. Ectopic expression of GRIK1-AS1 in gastric cancer cell lines significantly inhibits cellular viability, migration, and invasion. RNA-pull down and the luciferase activity assays show that GRIK1-AS1 mainly interacts specifically with miR-375. We further demonstrate a negatively regulatory relationship between lncRNA GRIK1-AS1 and miR-375. We discovered that IFIT2 was one of the direct key downstream target genes of miR-375, and established the important role of the GRIK1-AS1/miR-375/IFIT2 axis in the progression of gastric cancer. Taken together, our results revealed a novel mechanism of GRIK1-AS1 as a sponge to miR-375 that impacts gastric cancer progression via modulating target mRNA IFIT2 translation, and as a result, opens a new strategy to future GRIK1-AS1 based therapeutic development.

6.
Pathol Res Pract ; 216(2): 152778, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31831299

RESUMO

BACKGROUND: miRNA was recently detected as tumor suppressor or inducer in various cancers including gliomas. Due to the abnormal expression of miR-4262 in glioma cancer, we supposed that miR-4262 made efforts in proliferation and migration in glioma cancer. METHODS: CCK-8, Transwell migration Assay and Wound-healing assay were appraisal assays for cell proliferation and migration. qRT-PCR and western blot were performed to test the expression of miR-4262, MMP2, MMP13 and LATS1 in glioma cancers tissues and cancer cells. The targeting detection between miR-4262 and LATS1 was detected by luciferase reporter assay. RESULTS: miR-4262 expression was dramatically higher in glioma tumor tissues than in para-tumor control. Inhibition of miR-4262 in glioma cancer cells prominently inhibited cell proliferation and migration. Mechanically, downregulation of miR-4262 inhibited expression of matrix metalloproteinase (MMP) -2, -13. In addition, miR-4262 directly and negatively modulated expression of large tumor suppressor 1 (LATS1). Moreover, we discovered that overexpression of LATS1 could reverse the effects of miR-4262 on cell proliferation and migration, as well as the production of MMP-2, -13. CONCLUSIONS: In glioma cancer, miR-4262 regulated cell proliferation and migration mediated by LATS1. This indicated that miR-4262 is a tumor inducer in glioma cancer and may be a feasible target for glioma therapy.


Assuntos
Regulação Neoplásica da Expressão Gênica , Glioma/genética , MicroRNAs/genética , Proteínas Serina-Treonina Quinases/metabolismo , Adulto , Idoso , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Biologia Computacional , Progressão da Doença , Regulação para Baixo , Feminino , Glioma/patologia , Humanos , Masculino , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Pessoa de Meia-Idade , Proteínas Serina-Treonina Quinases/genética , Regulação para Cima
7.
Opt Express ; 27(26): 38109-38115, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31878582

RESUMO

We demonstrate a radio frequency (RF) phase-stable transmission over fiber based on microwave photonic phase shifter. In the proposed system, both assistant RF signals are applied to drive two arms of a dual-drive Mach-Zehnder modulator (DMZM), respectively. An optical bandpass filter is followed to filter out the first-order sideband of optical modulated signal. Due to the phase independence between two optical sidebands, the phase perturbation caused by fiber-length variations can be compensated automatically via controlling the direct-current bias voltage of the DMZM. We have performed RF transfer in a 155 km single-mode fiber with a frequency instability of 3.05 × 10-17 at 10,000 s averaging time.

8.
Opt Express ; 26(19): 24479-24486, 2018 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-30469564

RESUMO

In this paper, we propose an active-compensation stable radio frequency (RF) transmission scheme based on a high-performance phase lock loop (PLL). In our PLL, a new structure for phase-detection is designed with only one standard RF signal to obtain a simple structure with no interference from other signals. In addition, different optical wavelengths carrying the same RF signal are utilized in the two directions to suppress Rayleigh scattering. The low phase noise homemade bi-directional erbium doped fiber amplifier (EDFA) module is used to reduce signal-to-noise ratio (SNR) deterioration. Hence, the transmission distance is greatly improved. The effects of polarization mode dispersion and phase noise produced by the EDFA on the transmission distance are discussed. Ultimately, a stable RF signal with 2.4 GHz transmitted over a 1007 km fiber link is obtained. The experimental results demonstrate that frequency instabilities of 1.2×10- 13 at 1s and 5.1×10- 16 at 20000s. Therefore, the system can be used for atomic clocks comparisons and provides frequency standard for time transfer systems over a long-haul fiber.

9.
EBioMedicine ; 28: 105-113, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29396299

RESUMO

BACKGROUND: In the present study, we aimed to investigate the role of epidermal growth factor receptor (EGFR) pathway in the up-regulation of programmed death ligand-1 (PD-L1) caused by radiotherapy (RT). MATERIALS AND METHODS: Tissue microarrays (TMA) consisting of glioma cancer specimens from 64 patients were used to examine the correlation between PD-L1 and EGFR levels. Furthermore, we performed in vitro experiments to assess the role of EGFR pathway in RT-upregulated PD-L1 expression using human glioma cell lines U87 and U251. RESULTS: Our data demonstrated that the PD-L1 expression was significantly correlated with EGFR expression in glioma specimens (χ2=5.00, P=0.025). The expressions of PD-L1 at the protein and mRNA levels were both significantly up-regulated by RT (P<0.05). The expressions of phosphorylated EGFR and janus kinase 2 (JAK2) were also induced by RT (P<0.05). Besides, inhibition of EGFR pathway could abrogate the RT-triggered PD-L1 up-regulation (P>0.05). The combination of RT with EGFR inhibitor exhibited the same effect on antitumor immune response compared with the combination of RT with PD-L1 neutralizing antibody (Ab). CONCLUSIONS: RT could up-regulate the PD-L1 expression through the pathways downstream of EGFR in glioma.


Assuntos
Antígeno B7-H1/genética , Receptores ErbB/metabolismo , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/radioterapia , Regulação para Cima/genética , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Feminino , Glioma/imunologia , Glioma/patologia , Humanos , Evasão da Resposta Imune/efeitos da radiação , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Regulação para Cima/efeitos da radiação
10.
Oncotarget ; 8(23): 37435-37447, 2017 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-28415577

RESUMO

B7-H6, a new member of B7-family ligand, also known as NCR3LG1, plays an important role in NK cells mediated immune responses. Many studies have shown that it is highly expressed in various human cancers, and its expression levels are significantly associated with cancer patients' clinicopathological parameters and postoperative prognoses. But, still the exact role of B7-H6 expression in human glioma remains elusive. In the present study, we have characterized the B7-H6 expression in the human glioma tissues as well as glioma cell lines, U87 and U251. We observed that B7-H6 was highly expressed in the human glioma tissues, and its expression was significantly associated with cancer progression. By using the RNA interference technology, we successfully ablated B7-H6 expression in human glioma cell lines to further study its contribution towards various biological features of this malignancy. Our study identified that the B7-H6 knockdown in U87 and U251 glioma cells significantly suppressed cell proliferation, migration, invasion, and enhanced apoptosis along with induction of cell cycle arrest. It thus suggested that B7-H6 play an important role in the regulation of the biological behavior of these glioma cells. However, the detailed mechanism of B7-H6 mediated regulation of glioma cancer cell transformation and its prognostic value merits further investigation.


Assuntos
Antígenos B7/genética , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Apoptose/genética , Antígenos B7/metabolismo , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Feminino , Glioma/metabolismo , Glioma/patologia , Humanos , Masculino , Prognóstico , Interferência de RNA , Análise de Sobrevida
11.
Opt Express ; 24(20): 23376-23382, 2016 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-27828400

RESUMO

We propose and experimentally demonstrate a stable radio frequency (RF) phase dissemination scheme for a long-haul optical fiber loop link based on frequency mixing. Using a single optical source in both directions of the loop link, additional timing jitter caused by group velocity dispersion (GVD) can be eliminated. Impressive scalability provided by the optical link ensures that arbitrary-access node can obtain an RF signal with a stabilized phase to meet the requirements of multiple users. In our experiment, a 2.4 GHz RF signal is distributed to arbitrary points along a 100 km fiber-optic loop link steadily. Stabilities of the recovered signals from two accessing nodes are recorded. The root-mean-square (RMS) phase jitter of the received signal at either accessing node is reduced from 1.87 rad to no more than 0.027 rad during 1800-second measuring time.

12.
Neurol Sci ; 37(2): 219-26, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26466586

RESUMO

A growing body of evidence suggests that inflammation plays a crucial role in cerebral aneurysm initiation, progression, and rupture. High-mobility group box 1 (HMGB1) is a non-histone nuclear protein that can serve as an alarmin to drive the pathogenesis of inflammatory disease. The purpose of this study was to investigate the expression of HMGB1 in the wall of ruptured and unruptured human cerebral aneurysms. Human cerebral aneurysms (25 ruptured and 16 unruptured) were immunohistochemically stained for HMGB1. As controls, four specimens of the middle cerebral arteries obtained at autopsy were also immunostained. Immunofluorescence double staining was used to determine HMGB1 cellular distribution. HMGB1 was nearly undetectable in the controls. All aneurysm tissues stained positive for HMGB1 monoclonal antibody, and expression of HMGB1 was more abundant in ruptured aneurysm tissue than unruptured aneurysms (p < 0.05). Furthermore, the expression of HMGB1 had no correlation with aneurysm size and time resected after the rupture. HMGB1 nuclear immunoreactivity was co-localized with immunoreactivity of CD3 in T lymphocytes, CD20 in B lymphocytes, CD68 in macrophages, α-SMA in smooth muscle cells, and CD31 in endothelial cells. Cytoplasmic HMGB1 localization was also detected in macrophages and T lymphocytes. Taken together, HMGB1 is expressed in the wall of human cerebral aneurysms and is more abundant in ruptured aneurysms than in unruptured ones. These data indicate a possible role of HMGB1 in the pathophysiology of human cerebral aneurysms.


Assuntos
Aneurisma Roto/metabolismo , Proteína HMGB1/metabolismo , Aneurisma Intracraniano/metabolismo , Actinas/metabolismo , Adolescente , Adulto , Idoso , Antígenos CD/metabolismo , Células Endoteliais/metabolismo , Feminino , Humanos , Linfócitos/metabolismo , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Miócitos de Músculo Liso/metabolismo , Regulação para Cima , Adulto Jovem
13.
Brain Res ; 1622: 270-8, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26151898

RESUMO

BACKGROUND: Subarachnoid hemorrhage (SAH) is one of the life-threatening diseases with high morbidity and mortality rates. SUMO-specific proteases 3 (SENP3), a member of the small ubiquitin-like modifier specific protease family, was identified as an isopeptidase that deconjugates SUMOylation (The covalent modification by SUMO) of modified protein substrates. It is reported that SUMO-2/3 conjugation, a member of SUMOylation, presented neuroprotection. The study aimed to evaluate the expression of SENP3 and to explore its potential role in SAH. MATERIALS AND METHODS: A total of 108 Sprague Dawley (SD) rats were randomly divided into 2 parts experiment and 9 subgroups (part 1:Sham group, SAH group, SAH+NAC group, SAH+vehicle group; part 2: Sham group, SAH group, SAH+lv-SENP3 group, SAH+lv-null group, SAH+NS group). 7 days before SAH, lentivirus was administrated into rats׳ left lateral ventricle to down-regulate SENP3. Experimental SAH was imitated by injection with 0.3ml nonheparinized autoblood into the prechiasmatic cistern. MDA levels, SOD activities, and GSH contents were detected to evaluate oxidative stress level. SENP3 and cleaved caspase 3 were detected by western blot, apoptosis was observed by TUNEL staining. RESULTS: High oxidative stress level following SAH induced rising of SENP3. And inhibition of SENP3 by lentivirus induces suppression of apoptosis in experimental subarachnoid hemorrhage in rats. CONCLUSION: When SENP3 accumulated by high oxidative stress, caspase 3 activated subsequently. And it leads to more severe apoptosis than physiological.


Assuntos
Apoptose/fisiologia , Endopeptidases/metabolismo , Estresse Oxidativo/fisiologia , Hemorragia Subaracnóidea/fisiopatologia , Animais , Apoptose/genética , Caspase 3/metabolismo , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Modelos Animais de Doenças , Endopeptidases/genética , Vetores Genéticos , Glutationa/metabolismo , Lentivirus/genética , Masculino , Malondialdeído/metabolismo , Neurônios/patologia , Neurônios/fisiologia , Estresse Oxidativo/genética , RNA Interferente Pequeno , Distribuição Aleatória , Ratos Sprague-Dawley , Hemorragia Subaracnóidea/patologia , Hemorragia Subaracnóidea/terapia , Superóxido Dismutase/metabolismo
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