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1.
Aging (Albany NY) ; 12(9): 7761-7773, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32355035

RESUMO

Glioma is the most prevalent tumor of the central nervous system. To identify differentially expressed miRNAs (DEMs) in gliomas of different grades, bioinformatics analysis was performed. The DEMs between low-grade gliomas (LGGs) and high-grade gliomas (HGGs) were identified by screening the Gene Expression Omnibus and The Cancer Genome Atlas databases using the LIMMA package. Six overlapping DEMs were identified by comparing LGGs and HGGs. Downregulation of miR-1298-3p correlated with poor overall survival rates in glioma patients. Overexpression of miR-1298-3p induced apoptosis of glioma cells and inhibited glioma cell proliferation, migration, and invasion. The basement membrane protein Nidogen-1 (NID1) was identified as a direct binding target of miR-1298-3p in glioma cells. MiR-1298-3p agonist downregulated the NID1 and vimentin levels, but upregulated the level of E-cadherin in glioma cells. Importantly, overexpression of miR-1298-3p induced apoptosis and reduced tumor growth in a mouse xenograft model of glioma. Our results show that miR-1298-3p functions as a tumor suppressor in glioma cells, and suggest that it might serve as a potential biomarker and therapeutic target in glioma patients.

2.
Anal Chem ; 92(11): 7404-7408, 2020 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-32403919

RESUMO

Synthetic DNAzyme motors or machines hold great potential in the detection of intracellular microRNA (miRNA) and mRNA. However, to make intracellular DNAzyme motors or machines operate efficiently, adding exogenous metal ion cofactors as fuel is imperative, which limits their applications. Here, we reported a Na+-specific DNAzyme-based DNAzyme motor differentiating cell subtypes of nonsmall cell lung cancer by simultaneously sensing intracellular miRNA-21 and miRNA-205. The DNAzyme motor could be fueled by intracellular Na+, which avoids the necessity of adding exogenous cofactors. It could be also designed to detect other miRNAs or mRNAs by changing 12-nt DNA domain. Meanwhile, our DNAzyme motor had high sensitivity, excellent specificity, high biostability, and little cytotoxicity. Therefore, the miRNA-initiated and intracellular Na+-fueled DNAzyme motor can expand the application of DNAzyme motors or machines in sensing miRNA and has potential value in cancer clinical diagnosis and prognosis.

3.
Bioconjug Chem ; 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32463664

RESUMO

Although the extensive clinical use of the ADC trastuzumab-DM1(T-DM1) for human epidermal growth factor receptor 2 (HER2) targeted cancer therapy, many patients who initially respond to T-DM1 treatment eventually met the insufficient efficacy issue, which is partly attributed to the decreased amount of surface HER2 caused by HER2 degradation in target cells. In our study, we have engineered a HER2 targeted DNA aptamer-DM1 conjugate (HApDC) that can maintain the homeostasis of surface HER2 on the target cancer cell. These conclusions are supported by determining the efficient internalization of HApDC into HER2 overexpressed BT474 and SKBR3 cancer cell lines and by identifying the membranal HER2 level on HApDC-treated BT474 cells. Consistent with the impressive in vitro properties of our newly developed anticancer agent, DM1 could precisely be delivered to the tumor tissue in BT474 xenografted mouse models, because of the specific recognition of aptamer. Noteworthy, HApDC exhibited excellent in vivo tumor inhibition function with much lower healthy organ toxicity, compared with the free drug, which might be explained by the persistently targeted DM1 delivery, which is attributed to the remaining HER2 levels on cells.

4.
Neuroscience ; 438: 60-69, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32380270

RESUMO

Excessive expression of vascular endothelial growth factor (VEGF) is a common cause of blood-brain barrier (BBB) breakdown that triggers severe complications following traumatic brain injury (TBI). It has been shown that inhibition of VEGF activities may attenuate cerebral edema in pathological conditions. Vascular endothelial growth inhibitor (VEGI; also known as TNFSF15), a cytokine produced largely by vascular endothelial cells, is capable of downregulating VEGF expression and inhibiting VEGF receptor-2 (VEGFR2) activation. In this study we found that TBI can cause breakdown of BBB and sharp increases of VEGF/VEGI and Angpt2/Angpt1 ratios in the injured tissues. VEGI treatment resulted in a marked decrease of BBB permeability and concomitant restoration of normal ratios of VEGF/VEGI and Angpt2/Angpt1. Consistently, alleviated edema, decreased neuron cell death, and improved neurological functions were observed when the experimental animals were treated with VEGI in the early phase of TBI. Our findings suggest that administration of VEGI recombinant protein at early phases of TBI is beneficial to stabilization of the disease conditions.

5.
Int J Mol Med ; 46(1): 289-299, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32319551

RESUMO

The aim of the present study was to investigate the role of the long non­coding (lnc)RNA PART1 in nucleus pulposus (NP) cells derived from patients with intervertebral disc degeneration (IDD). The level of PART1 in degenerative NP tissues from patients with IDD, bulging and herniated discs was measured by reverse transcription­quantitative PCR (RT­qPCR) analysis. NP cells were isolated from patients with IDD and transfected with siPART1, after which time the growth ability of the NP cells was evaluated by Cell Counting Kit­8 and colony formation assays, and cell apoptosis was measured by flow cytometry. The levels of the cell proliferation marker Ki­67 and the apoptosis marker cleaved caspase­3, and the levels of genes related to extracellular matrix (ECM) synthesis and degradation, were also evaluated by western blotting and RT­qPCR, as appropriate. Bioinformatics methods predicted that miR­93 was sponged by PART1, and matrix metallopeptidase (MMP)2 was targeted by miR­93, which was further confirmed by dual­luciferase reporter assay. The levels of miR­93 and MMP2 were also measured in NP tissues, and further rescue experiments were performed to confirm the role of the PART1/miR­93/MMP2 pathway in NP cells. PART1 was found to be upregulated in degenerative NP tissues, and siPART1 caused an increase in cell growth ability and ECM synthesis, whereas it decreased cell apoptosis and ECM degradation in NP cells. miR­93 was downregulated and MMP2 was upregulated in degenerative NP tissues. Rescue experiments indicated that the effects of miR­93 inhibitor on NP cells were abolished by siPART1, and the effect of miR­93 mimic on NP cells was rescued by MMP2 overexpression. Thus, the results of the present study demonstrated that PART1 may regulate NP cell degeneration through the miR­93/MMP2 pathway. These findings indicate a novel signaling axis in NP cells that may be explored for the treatment of IDD.

6.
J Clin Lab Anal ; : e23336, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32298022

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is associated with an increased cardiovascular disease (CVD) mortality risk. Elevation of cardiac biomarkers in patients with renal dysfunction is ambiguous in the diagnosis of CVD. The purpose of this study was to investigate the associations between estimated glomerular filtration rate (eGFR) and cardiac biomarkers, and the influence of renal dysfunction on the cardiac biomarkers. METHODS: We examined the cross-sectional associations of eGFR with cardiac troponin I (cTnI), creatine kinase (CK), CK-MB, lactic dehydrogenase (LDH), hydroxybutyrate dehydrogenase (HBDH), and brain natriuretic peptide (BNP) in 812 adults and 215 child. Spearman correlation and logistic regression analysis were performed to evaluate the associations. RESULTS: For adults, lower eGFR CKD-EPI had significantly higher cTnI, CK-MB, LDH, HBDH, and BNP. There were negative correlations between eGFRCKD-EPI and cTnI, CK-MB, LDH, HBDH, and BNP. After adjustment for potential confounders, as compared with eGFRCKD-EPI  ≥ 90 mL/min/1.73 m2 , eGFRCKD-EPI  < 60 mL/min/1.73 m2 remained associated with a 2.83 (1.08-7.41) [ratio (95% CI)] times higher cTnI and a 6.50 (2.32-18.22) [ratio (95% CI)] times higher HBDH. For child, lower eGFRSchwartz had significant higher CK and CK-MB. There were negative correlations between eGFRSchwartz and CK, and eGFRSchwartz and CK-MB. After adjustment for potential confounders, as compared with eGFRSchwartz  ≥ 90 mL/min/1.73 m2 , eGFRSchwartz  < 90 mL/min/1.73 m2 revealed no significant higher CVD biomarkers. CONCLUSION: Reduced eGFR is associated with elevated cTnI and HBDH among adults without clinically evident CVD, but not child.

7.
Haematologica ; 105(1): 209-217, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30975909

RESUMO

Coagulopathy often develops soon after acute traumatic brain injury and its cause remains poorly understood. We have shown that injured brains release cellular microvesicles that disrupt the endothelial barrier and induce consumptive coagulopathy. Morphologically intact extracellular mitochondria accounted for 55.2% of these microvesicles, leading to the hypothesis that these extracellular mitochondria are metabolically active and serve as a source of oxidative stress that activates platelets and renders them procoagulant. In testing this hypothesis experimentally, we found that the extracellular mitochondria purified from brain trauma mice and those released from brains subjected to freeze-thaw injury remained metabolically active and produced reactive oxygen species. These extracellular mitochondria bound platelets through the phospholipid-CD36 interaction and induced α-granule secretion, microvesiculation, and procoagulant activity in an oxidant-dependent manner, but failed to induce aggregation. These results define an extracellular mitochondria-induced and redox-dependent intermediate phenotype of platelets that contribute to the pathogenesis of traumatic brain injury-induced coagulopathy and inflammation.

8.
Semin Thromb Hemost ; 46(2): 167-175, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31887759

RESUMO

Traumatic brain injury (TBI) induced coagulopathy remains a significant clinical challenge, with unmet needs for standardizing diagnosis and optimizing treatments. TBI-induced coagulopathy is closely associated with poor outcomes in affected patients. Recent studies have demonstrated that TBI induces coagulopathy, which is mechanistically distinct from the deficient and dilutional coagulopathy found in patients with injuries to the body/limbs and hemorrhagic shock. Multiple causal and disseminating factors have been identified to cause TBI-induced coagulopathy. Among these are extracellular mitochondria (exMTs) released from injured cerebral cells, endothelial cells, and platelets. These circulating exMTs not only express potent procoagulant activity but also promote inflammation, and could remain metabolically active to become a major source of oxidative stress. They activate platelets and endothelial cells to propagate TBI-induced coagulopathy and secondary tissue injury after primary traumatic impact. In this review, we discuss recent advances in our understanding of the role of exMTs in the development of TBI-induced coagulopathy.

9.
Cancer Cell Int ; 19: 326, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827400

RESUMO

Background: Osteosarcoma (OS) is still a disease with high mortality from malignant tumors in children and adolescents. Due to its poor treatment, this study explored the involvement of lncRNA ZFAS1/microRNA-135a (miR-135a)/apurinic/apyrimidinic exonuclease 1 (APEX1) axis in the regulation of OS growth and metastasis. Methods: ZFAS1, miR-135a and APEX1 expression in OS tissues and cells were tested by RT-qPCR and western blot analysis. MG63 cells were transfected with sh-ZFAS1, miR-135a mimic or their controls to unearth theirs functions in the proliferation, colony formation, migration, invasion, cycle entry and apoptosis of MG63 cells by MTT and EdU, colony formation assays, flow cytometry, and Transwell assay, severally. The proliferation related factor (Ki-67, CyclinD1), apoptosis related factor (Bax, Bcl-2) and migration related factor (MMP2, MMP9) protein levels were tested. Tumor volume and weight were detected by subcutaneous tumor xenograft in nude mice. Results: Overexpressed ZFAS1 and APEX1, and down-regulated miR-135a existed in OS tissues and cells. Silenced ZFAS1 or elevated miR-135a inhibited colony formation and proliferation, cycle progression, migration and invasion while promoted apoptosis of MG63 cells. Silenced ZFAS1 or elevated miR-135a suppressed tumor volume and weight of OS in vivo. LncRNA ZFAS1 promoted APEX1 expression by competitively binding with miR-135a. Conclusion: This study indicates that silenced ZFAS1 or up-regulated miR-135a restrained migration, proliferation and invasion and promoted apoptosis of OS MG63 cells. This study provides a possible theoretical basis for studying the regulatory mechanism of ZFAS1/miR-135a/APEX1 signaling axis on the growth and metastasis of OS.

10.
Sci Rep ; 9(1): 16227, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31700055

RESUMO

The complexity of the leaf constitution of foxtail millet (Setaria italica (L.) P. Beauv.) makes it difficult to obtain high-purity cpDNA. Here, we developed a protocol to isolate high-quality cpDNA from foxtail millet and other crops. The new protocol replaces previous tissue grinding and homogenization by enzyme digestion of tiny leaf strips to separate protoplasts from leaf tissue and protects chloroplasts from damage by undue grinding and homogenization and from contamination of cell debris and nuclear DNA. Using the new protocol, we successfully isolated high-quality cpDNAs for whole-genome sequencing from four foxtail millet cultivars, and comparative analysis revealed that they were approximately 27‰ longer than their reference genome. In addition, six cpDNAs of four other species with narrow and thin leaf blades, including wheat (Triticum aestivum L.), maize (Zea may L.), rice (Oryza sativa L.) and sorghum (Sorghum bicolor (L.) Moench), were also isolated by our new protocol, and they all exhibited high sequence identities to their corresponding reference genomes. A maximum-likelihood tree based on the chloroplast genomes we sequenced here was constructed, and the result was in agreement with previous reports, confirming that these cpDNA sequences were available for well-supported phylogenetic analysis and could provide valuable resources for future research.

11.
J Am Chem Soc ; 141(46): 18421-18427, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31584808

RESUMO

Aptamers and antibodies, as molecular recognition probes, play critical roles in cancer diagnosis and therapy. However, their recognition ability is based on target overexpression in disease cells, not target exclusivity, which can cause on-target off-tumor effects. To address the limitation, we herein report a novel strategy to develop a conditional aptamer conjugate which recognizes its cell surface target, but only after selective activation, as determined by characteristics of the disease microenvironment, which, in our model, involve tumor hypoxia. This conditional aptamer is the result of conjugating the aptamer with PEG5000-azobenzene-NHS, which is responsive to hypoxia, here acting as a caging moiety of conditional recognition. More specifically, the caging moiety is unresponsive in the intact conjugate and prevents target recognition. However, in the presence of sodium dithionite or hypoxia (<0.1% O2) or in the tumor microenvironment, the caging moiety responds by allowing conditional recognition of the cell-surface target, thereby reducing the chance of on-target off-tumor effects. It is also confirmed that the strategy can be used for developing a conditional antibody. Therefore, this study demonstrates an efficient strategy by which to develop aptamer/antibody-based diagnostic probes and therapeutic drugs for cancers with a unique hypoxic microenvironment.

12.
Anal Chem ; 91(21): 13349-13354, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31588733

RESUMO

Biomarker receptors on cancer cells can sense and recruit extracellular ligands and ligand-conjugated imaging agents/drugs, providing a critical basis upon which to develop an active tumor-targeting strategy. However, such a strategy can be confounded by both the limited number of cancer biomarker receptors and the inherent heterogeneity of cancer cells. Therefore, we herein report a simple strategy to deploy an exogenous physical label on the surface of cancer cells as an artificial receptor (AR) for active tumor targeting. It can be driven by the tumor extracellular acidic microenvironment to insert into the plasma membrane of cancer cells. Our studies demonstrated that an AR could efficiently sense and recruit the extracellular imaging agent Cy5-streptavidin conjugate to cancer cells, cancer cell spheroids, and an in vivo tumor. Based on the easy synthesis and chemical modification diversity of the peptide, our AR holds promise as a novel tumor-targeted strategy.

13.
Oncol Rep ; 42(6): 2390-2401, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31638257

RESUMO

Glioma patients receiving therapy are at a high risk of relapse and rapid progression and, thus, more effective treatments are required. The aim of the present study was to determine the suppressive role of miR­489 as an alternative therapeutic target for preventing glioma progression. The results of the present study demonstrated that patients with relatively lower levels of expression of miR­489 had more favorable clinical outcomes. Furthermore, miR­489 expression was inversely correlated with p21­activated kinase 5 (PAK5) mRNA expression levels in glioma specimens. A dual luciferase reporter assay revealed that miR­489 suppressed PAK5 expression by directly targeting the PAK5 3'­untranslated region. The effects of miR­489 on cell viability were measured using MTT and Cell Counting Kit­8 assays. The results demonstrated that ectopic expression of miR­489 mimic decreased cell viability by interfering with cyclin D1 and c­Myc signaling. Additionally, the effect of miR­489 on apoptosis was determined using Hoechst 33258 staining and flow cytometry. The results demonstrated that miR­489 decreased the activity of RAF1, reduced Bcl­2 and promoted Bax expression, resulting in increased cell apoptosis. Furthermore, the effect of miR­489 mimic on cellular motility was assessed using migration and invasion assays. miR­489 was shown to abolish the PAK5/RAF1/MMP2 pathway, resulting in decreased cell invasion ability. These results indicated that miR­489 may be involved in PAK5­mediated regulation of glioma progression, demonstrating the potential therapeutic benefits of targeting miR­489 in glioma.


Assuntos
Apoptose , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-raf/metabolismo , Quinases Ativadas por p21/metabolismo , Biomarcadores Tumorais/genética , Proliferação de Células , Glioma/genética , Glioma/metabolismo , Humanos , Invasividade Neoplásica , Prognóstico , Proteínas Proto-Oncogênicas c-raf/genética , Taxa de Sobrevida , Células Tumorais Cultivadas , Quinases Ativadas por p21/genética
14.
Haematologica ; 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31439676

RESUMO

Preeclampsia is a pregnancy-induced condition that impairs mother's health and results in pregnancy termination or premature delivery. Elevated levels of placenta-derived extracellular vesicles in the circulation have been consistently associated with preeclampsia, but whether placenta-derived extracellular vesicles induce preeclampsia or are merely the product of preeclampsia is not known. Guided by a small cohort study of preeclampsia patients, we examined the impact of placenta-derived extracellular vesicles on the pathogenesis of preeclampsia in mouse models. We found that placenta-derived extracellular vesicles were detected in pregnant C56BL/6J mice with a peak level of 3.8+/-0.9x107/ml in 17-18 days post-coitum. However, these pregnant mice developed hypertension and proteinuria only after being infused with these vesicles purified from injured placenta. These injured placenta-released extracellular vesicles disrupted the endothelial integrity and induced vasoconstriction. Enhancing the clearance of extracellular vesicles prevented the development of the extracellular vesicle-induced preeclampsia in mice. Our results demonstrate a causal role of placenta-derived extracellular vesicles in preeclampsia and identify microvesicle clearance as a new therapeutic target for the treatment of this pregnancy-associated complication.

15.
Theranostics ; 9(11): 3262-3279, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244953

RESUMO

The elegant properties of deoxyribonucleic acid (DNA), such as accurate recognition, programmability and addressability, make it a well-defined and promising material to develop various molecular probes, drug delivery carriers and theranostic systems for cancer diagnosis and therapy. In addition, supramolecular chemistry, also termed "chemistry beyond the molecule", is a promising research field that aims to develop functional chemical systems by bringing discrete molecular components together in a manner that invokes noncovalent intermolecular forces, such as hydrophobic interaction, hydrogen bonding, metal coordination, and shape or size matching. Thus, DNA-supramolecule conjugates (DSCs) combine accurate recognition, programmability and addressability of DNA with the greater toolbox of supramolecular chemistry. This review discusses the applications of DSCs in sensing, protein activity regulation, cell behavior manipulation, and biomedicine.

16.
Angew Chem Int Ed Engl ; 58(34): 11661-11665, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-31125154

RESUMO

Polytherapy (or drug combination cancer therapy (DCCT)), targeting multiple mechanisms associated with tumor proliferation, can efficiently maximize therapeutic efficacy, decrease drug dosage, and reduce drug resistance. However, most DCCT strategies cannot coordinate the specific delivery of a drug combination in an accurately tuned ratio into cancer cells. To address these limitations, the present work reports the engineering of circular bivalent aptamer-drug conjugates (cb-ApDCs). The cb-ApDCs exhibit high stability, specific recognition, excellent cellular uptake, and esterase-triggered release. Furthermore, the drug ratios in cb-ApDCs can be tuned for an enhanced synergistic effect without the need for complex chemistry. Therefore, cb-ApDCs provide a promising platform for the development of DCCT strategies for different drug combinations and ratios.

17.
J Cell Biochem ; 120(10): 17472-17480, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31106473

RESUMO

In this study, we aimed to explore the time-course relating to the pathological progression of Cutaneous T-cell lymphoma (CTCL) and to identify the early changes in gene expression. The raw microarray data of CTCL was downloaded from the Gene Expression Omnibus database and a weighted gene coexpression network analysis was performed. A total of 2183 genes that positively correlated with the time course of CTCL development were identified in as part of the turquoise module as well as 1096 genes negatively correlated with the time course of CTCL development, which was identified in the blue module. To better understand the effects of these genes on prognosis, we further performed the Spearman correlation analysis, univariate Cox regression analysis, and Kaplan-Meier survival analysis. We identified 10 differentially expressed genes whose expression was significantly associated with prognosis in patients with CTCL. Our findings can help our understanding of the underlying mechanisms of CTCL as well as the development of novel drugs.

18.
Sci Rep ; 9(1): 4365, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30867435

RESUMO

Mg-7Zn-5Gd-0.6Zr (wt%) alloy strengthened with quasicrystal phase (I-Mg3Zn6Gd phase) is prepared through hot extrusion and subsequent heat treatments. The low temperature (range from 25 °C to 250 °C) superplastic deformation behavior of the as-extruded, aging treated (T5) and solution and aging treated (T6) alloys are investigated. The results reveal that a superior superplastic elongation of 863% is obtained at 250 °C and strain rate of 1.67 × 10-3 s-1 and the elongation of this alloy increases with the increasing tensile temperature. Detailed microstructural analyses show that I-Mg3Zn6Gd phase and W-Mg3Gd2Zn3 phase are crushed into small particles during extrusion. A high density of nanoscale I-phase precipitates after T5 treatment. Dynamic recrystallization occurs in as-extruded Mg-7Zn-5Gd-0.6Zr alloy. The T5-treated Mg-7Zn-5Gd-0.6Zr alloy shows a relatively weak basal texture intensity, a large number fraction of high angle boundaries and a very finer grain structure (3.01 µm). During superplastic deformation, the nanoscale I-phase is slightly elongated and the microstructure is still equiaxed grains. The superplastic mechanism of the alloy is grain boundary sliding (GBS) accommodated by dislocation movement and static recrystallization. The cavity nucleation at the nanoscale I-phase/α-Mg matrix boundaries or grain boundaries and the cavity stringer formation leads to final fracture.

19.
Oncol Rep ; 41(4): 2453-2463, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30816477

RESUMO

Deoxypodophyllotoxin (DPT) is a natural chemical that has been demonstrated to inhibit cellular viability and motility in various cancer cell types. Although previous studies have indicated that programmed cell death and cell cycle arrest are involved in the suppression of glioma development by DPT, the underlying mechanism has not been fully explored. Different methods were used to the elucidate the mechanisms of DPT that inhibit the malignant behavior of glioma cells. Cellular viability was assessed by MTT assay. Relative protein and mRNA expression levels were detected by western blot analysis and reverse transcription­quantitative polymerase chain reaction analyses, respectively. Cell cycle distribution and the apoptosis rate were detected by flow cytometry. Hochest 33258 staining was also performed to detect apoptosis. Transwell assays without and with Matrigel were used to assess migration and invasion abilities, respectively. It was determined that DPT suppressed cellular viability by inducing cell cycle arrest at the G1/S phase by targeting the phosphatidylinositol 4,5­bisphosphate 3­kinase (PI3K)/RAC­α serine/threonine­protein kinase (Akt)­cyclin­dependent kinase inhibitor 1­cyclin­dependent kinase 2/cyclin E signaling cascades. Additionally, DPT significantly enhanced apoptosis by attenuating the PI3K/Akt­mediated suppression of Bcl­2­associated agonist of cell death expression, which was accompanied by an increased apoptosis regulator BAX/apoptosis regulator Bcl­2 ratio. Furthermore, DPT downregulated the invasiveness of glioma cells by hindering PI3K/Akt­matrix metalloproteinase (MMP)9/MMP2 signaling pathways. In conclusion, DPT effectively inhibited the expression of PI3K and downregulated PI3K/Akt­mediated signaling pathways to prevent glioblastoma progression.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Glioblastoma/tratamento farmacológico , Podofilotoxina/análogos & derivados , Transdução de Sinais/efeitos dos fármacos , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Astrócitos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/patologia , Humanos , Invasividade Neoplásica/patologia , Invasividade Neoplásica/prevenção & controle , Fosfatidilinositol 3-Quinases/metabolismo , Podofilotoxina/farmacologia , Podofilotoxina/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sequiviridae/química
20.
Metabolism ; 94: 88-95, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30831144

RESUMO

OBJECTIVE: Low-density lipoprotein cholesterol (LDL-C) is the hallmark of atherosclerotic cardiovascular diseases. The hepatic LDL receptor (LDLR) plays an important role in clearance of circulating LDL-C. PCSK9 facilitates degradation of LDLR in the lysosome and antagonizing PCSK9 has been successfully used in the clinic to reduce blood LDL-C level. Here we identify a new player that modulates LDLR interaction with PCSK9, thus controlling LDLR degradation and cholesterol homeostasis. METHODS: The blood LDL-C and cholesterol levels were analyzed in mice with hepatic deletion of Paqr3 gene. The half-life of LDLR was analyzed in HepG2 cells. The interaction of PAQR3 with LDLR and PCSK9 was analyzed by co-immunoprecipitation and immunofluorescent staining. RESULTS: The blood LDL-C and total cholesterol levels in the mice with hepatic deletion of Paqr3 gene were significantly lower than the control mice after feeding with high-fat diet (p < 0.001 and p < 0.05 respectively). The steady-state level of LDLR protein is elevated by Paqr3 knockdown/deletion and reduced by PAQR3 overexpression. The half-life of LDLR protein is increased by Paqr3 knockdown and accelerated by PAQR3 overexpression. PAQR3 interacts with the ß-sheet domain of LDLR and the P-domain of PCSK9 respectively. In addition, PAQR3 can be localized in early endosomes and colocalized with LDLR, PCSK9 and LDL. Mechanistically, PAQR3 enhances the interaction between LDLR and PCSK9. CONCLUSION: Our study reveals that PAQR3 plays a pivotal role in controlling hepatic LDLR degradation and blood LDL-C level via modulating LDLR-PCSK9 interaction.


Assuntos
Colesterol/sangue , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/metabolismo , Animais , LDL-Colesterol/sangue , Células Hep G2 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fígado/metabolismo , Camundongos , Ligação Proteica/efeitos dos fármacos
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