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1.
Biochem Biophys Res Commun ; 695: 149424, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38169186

RESUMO

Liver cancer is the fourth most lethal cancer, but the treatment options for liver cancer are usually limited. Metabolic reprogramming is a hallmark of malignancy, ensuring activated cell glycolysis and increased macromolecular precursors required for the proliferation and migration of exuberant cancer cells. MicroRNAs (miRNAs) have been reported to participate in cancer metabolic shifts mainly by directly silencing the expression of specific genes. Here, we identified miR-148a-3p as a negative regulator for glycometabolism and cell proliferation in liver cancer. miR-148a-3p directly targets the 3'UTR of transmembrane protein 54 (TMEM54), leading to the significant inhibition of lactate production, glucose consumption, intracellular ATP level and extracellular acidification rate (ECAR), as well as the repression of the proliferation and colony formation ability of liver cancer cells. miR-148a-3p expression is often down-regulated in liver cancer tissues. In addition, there was a negative correlation between the expression levels of miR-148a-3p and TMEM54 in liver cancer tissues. Moreover, the low miR-148a-3p expression levels or high TMEM54 expression levels were associated with poorer prognosis in hepatocellular carcinoma (HCC) patients. Together, these findings support that the miR-148a-3p/TMEM54 regulatory pathway regulates the glycometabolism and cell proliferation in liver cancer, which is a possible target for the diagnosis and treatment of liver cancer.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , MicroRNAs/genética , MicroRNAs/metabolismo
2.
Sensors (Basel) ; 24(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38931813

RESUMO

Electric pylons are crucial components of power infrastructure, requiring accurate detection and identification for effective monitoring of transmission lines. This paper proposes an innovative model, the EP-YOLOv8 network, which incorporates new modules: the DSLSK-SPPF and EMS-Head. The DSLSK-SPPF module is designed to capture the surrounding features of electric pylons more effectively, enhancing the model's adaptability to the complex shapes of these structures. The EMS-Head module enhances the model's ability to capture fine details of electric pylons while maintaining a lightweight design. The EP-YOLOv8 network optimizes traditional YOLOv8n parameters, demonstrating a significant improvement in electric pylon detection accuracy with an average mAP@0.5 value of 95.5%. The effective detection of electric pylons by the EP-YOLOv8 demonstrates its ability to overcome the inefficiencies inherent in existing optical satellite image-based models, particularly those related to the unique characteristics of electric pylons. This improvement will significantly aid in monitoring the operational status and layout of power infrastructure, providing crucial insights for infrastructure management and maintenance.

3.
Alzheimers Dement ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38938161

RESUMO

INTRODUCTION: To investigate the role of a novel type of protein kinase C delta (PKCδ) in the neuroinflammation of Alzheimer's disease (AD). METHODS: We analyzed PKCδ and inflammatory cytokines levels in cerebrospinal fluid (CSF) of AD and normal controls, as well as their correlations. The cellular expression pattern of PKCδ and the effects of PKCδ modulation on microglia-mediated neuroinflammation were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR), western blot, RNA sequencing (RNA-seq), and immunofluorescence staining. RESULTS: PKCδ levels were increased dramatically in the CSF of AD patients and positively correlated with cytokines. PKCδ is expressed mainly in microglia in the brain. Amyloid beta (Aß) stimulation increased PKCδ expression and secretion, which led to upregulation of the nuclear factor kappa B (NF-κB) pathway and overproduction of proinflammatory cytokines. Downregulation or inhibition of PKCδ attenuated Aß-induced microglial responses and improved cognitive function in an AD mouse model. DISCUSSION: Our study identifies PKCδ as a potential biomarker and therapeutic target for microglia-mediated neuroinflammation in AD. HIGHLIGHTS: Protein kinase C delta (PKCδ) levels increase in cerebrospinal fluid (CSF) of patients with Alzheimer's disease (AD), and positively correlate with elevated inflammatory cytokines in human subjects. PKCδ is expressed mainly in microglia in vivo, whereas amyloid beta (Aß) stimulation increases PKCδ expression and secretion, causing upregulation of the nuclear factor kappa B (NF-κB) pathway and production of inflammatory cytokines. Downregulation or inhibition of PKCδ attenuates Aß-enhanced NF-κB signaling and cytokine production in microglia and improves cognitive function in AD mice. PKCδ serves as a potential biomarker and therapeutic target for microglia-mediated neuroinflammation in AD.

4.
J Neurosci ; 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35944999

RESUMO

Conversion of astroglia into functional neurons has been considered as a promising therapeutic strategy for neurodegenerative diseases. Recent studies reported that downregulation of the RNA binding protein, PTBP1, converts astrocytes into neurons in situ in multiple mouse brain regions, consequently improving pathological phenotypes associated with Parkinson's disease, RGC loss, and aging. Here, we demonstrate that PTBP1 downregulation using an astrocyte specific AAV-mediated shRNA system fails to convert hippocampal astrocytes into neurons in both male and female WT, and ß-amyloid (5×FAD) and tau (PS19) Alzheimer's disease (AD) mouse models, and fails to reverse synaptic/cognitive deficits and AD-associated pathology in male mice. Similarly, PTBP1 downregulation cannot convert astrocytes into neurons in the striatum and substantia nigra in both male and female WT mice. Together, our study suggests that cell fate conversion strategy for neurodegenerative disease therapy through manipulating one single gene, such as PTBP1, warrants more rigorous scrutiny.Significance Statement:Our results do not support some of the recent extraordinary and revolutionary claims that resident astrocytes can be directly and efficiently converted into neurons. Our study is critical for the field of neural regeneration and degeneration. In addition, our study is financially important because it may prevent other researchers/organizations wasting a vast amount of time and resources on the relevant investigations.

5.
J Neuroinflammation ; 20(1): 134, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37259140

RESUMO

BACKGROUND: Mutations in colony-stimulating factor 1 receptor (CSF1R) are known to cause adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP), which has been recently demonstrated as a primary microgliopathy characterized by cognitive impairment. Although the molecular mechanism underlying CSF1R-mediated microgliopathy remains unclear, therapeutic strategies have generally targeted modulation of microglial function. In particular, the microglial inhibitor, minocycline, has been shown to attenuate learning and memory deficits in several neurodegenerative diseases. The objectives of this study were to investigate the pathogenic mechanisms underlying ALSP and to explore the therapeutic effects of minocycline in an in vivo model of ALSP. We hypothesized that inhibiting microglial activation via minocycline could reverse the behavior and pathological defects in ALSP model mice. METHODS: We generated a Csf1r haploinsufficiency mouse model of ALSP using CRISPR/Cas9 genome editing and conducted electrophysiological recordings of long-term potentiation (LTP) and behavioral tests to validate the recapitulation of clinical ALSP characteristics in 8- to 11-month-old mice. RNA-sequencing was used to explore enriched gene expression in the molecular pathogenesis of ALSP. Microglial activation was assessed by immunofluorescent detection of Iba1 and CD68 in brain sections of male ALSP mice and pro-inflammatory activation and phagocytosis were assessed in Csf1r+/- microglia. Therapeutic effects were assessed by behavioral tests, histological analysis, and morphological examination after four weeks of intraperitoneal injection with minocycline or vehicle control in Csf1r+/- mice and wild-type control littermates. RESULTS: We found that synaptic function was reduced in LTP recordings of neurons in the hippocampal CA1 region, while behavioral tests showed impaired spatial and cognitive memory specifically in male Csf1r+/- mice. Increased activation, pro-inflammatory cytokine production, and enhanced phagocytic capacity were also observed in Csf1r+/- microglia. Treatment with minocycline could suppress the activation of Csf1r+/- microglia both in vitro and in vivo. Notably, the behavioral and pathological deficits in Csf1r+/- mice were partially rescued by minocycline administration, potentially due to inhibition of microglial inflammation and phagocytosis in Csf1r+/- mice. CONCLUSIONS: Our study shows that CSF1R deficiency results in aberrant microglial activation, characterized by a pro-inflammatory phenotype and enhanced phagocytosis of myelin. Our results also indicate that microglial inhibition by minocycline can ameliorate behavioral impairment and ALSP pathogenesis in CSF1R-deficient male mice, suggesting a potential therapeutic target for CSF1R-related leukoencephalopathy. Collectively, these data support that minocycline confers protective effects against CSF1R-related microgliopathy in male ALSP model mice.


Assuntos
Leucoencefalopatias , Minociclina , Masculino , Animais , Camundongos , Minociclina/farmacologia , Minociclina/uso terapêutico , Neuroglia/metabolismo , Leucoencefalopatias/etiologia , Leucoencefalopatias/genética , Encéfalo/metabolismo , Microglia/metabolismo , Receptores de Fator Estimulador de Colônias/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo
6.
J Neuroinflammation ; 19(1): 259, 2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36273158

RESUMO

BACKGROUND: Autoimmune encephalitis (AE) with neuronal surface antibodies (NSAbs) presents pathogenesis mediated by B cell-secreting antibodies. Rituximab is a second-line choice for the treatment for AE with NSAbs, which can cause B cell depletion via targeting CD20. However, the optimal protocol and dosage of rituximab combined with first-line therapy for NSAbs-associated AE remains unclear so far. In this study, we explored the efficacy and safety of low-dose rituximab combined with first-line treatment for NSAbs-associated AE. METHODS: Fifty-nine AE patients with NSAbs were enrolled, and retrospectively divided into common first-line therapy (41 patients) and combined low-dose rituximab (100 mg induction weekly with 3 circles, followed by 100 mg reinfusion every 6 months) with first-line therapy (18 patients). Outcome measures included changes in the Clinical Assessment Scale for Autoimmune Encephalitis (CASE) score (primary endpoint), changes in the modified Rankin Scale (mRS), the Mini-mental State Examination (MMSE), the patient and caregiver Neuropsychiatric Inventory (NPI) score at each visit (baseline, discharge, 6 months, 12 months and last follow-up) between two groups (secondary endpoint), as well as oral prednisone dosage, relapse and adverse effects during follow-up. RESULTS: Compared with traditional first-line therapy group, for primary outcome, CASE scores at last follow-up were significantly improved in combined rituximab group, as well as markedly improving changes of CASE scores between baseline and each visit. While changes of mRS, MMSE and NPI scores, as secondary endpoint, were all markedly accelerating improvement between baseline and each visit, as well as both oral prednisone dosage and relapse were also greatly reduced during follow-up. Meanwhile, longitudinal analysis in combination of rituximab cohort also revealed persistently marked amelioration in a series of scales from baseline even more than 1 year. Moreover, analysis in rituximab subgroup showed no difference in any clinical outcomes between combination with single first-line and with repeated first-line treatment (≥ 2 times), while compared to delayed combination with rituximab (> 3 months), early initiation of combination (≤ 3 months) might achieve better improvements in CASE and MMSE assessment even 1 year later. No rituximab-correlated serious adverse events have been reported in our patients. CONCLUSIONS: Our simplified regimen of combined low-dose rituximab firstly showed significantly accelerating short-term recovery and long-term improvement for AE with NSAbs, in parallel with markedly reduced prednisone dosage and clinical relapses. Moreover, opportunity of protocol showed earlier initiation (≤ 3 months) with better long-term improvement.


Assuntos
Encefalite , Humanos , Rituximab/uso terapêutico , Prednisona , Estudos Retrospectivos , Encefalite/tratamento farmacológico , Encefalite/induzido quimicamente , Recidiva
7.
Hepatology ; 73(5): 1764-1782, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32869873

RESUMO

BACKGROUND AND AIMS: Long noncoding RNAs (lncRNAs) are involved in almost every stage of tumor initiation and progression. Here, we have identified an antisense lncRNA, LINC00624, that arises from the antisense strand of chromo-domain-helicase-DNA-binding protein 1-like (CHD1L), located on chr1q21.1, with significant copy number gain and transcriptional activation of CHD1L and B-cell CLL/lymphoma 9 protein (BCL9), in hepatocellular carcinoma (HCC). APPROACH AND RESULTS: Overexpression of LINC00624 enhances tumor growth and metastasis in vitro and in vivo. Mechanistically, higher levels of LINC00624 strengthen the interaction between histone deacetylase 6 (HDAC6) and tripartite motif containing 28 (TRIM28), which accelerates HDAC6 ubiquitination and degradation. Moreover, LINC00624 binds to the RBCC domain of TRIM28, inhibits trimer formation, and weakens the interaction between TRIM28 and zinc finger protein 354C (ZNF354C). Thus, LINC00624 overexpression disrupts the formation of the HDAC6-TRIM28-ZNF354C transcriptional corepressor complex, resulting in the dissociation of the complex from the promoter of CHD1L and BCL9, thereby removing transcription inhibition. CONCLUSIONS: Our findings suggest that LINC00624 acts as a molecular decoy that sequesters the HDAC6-TRIM28-ZNF354C transcriptional corepressor complex away from the specific genomic loci, and that it can potentially be a therapeutic target in HCC.


Assuntos
Carcinoma Hepatocelular/patologia , Desacetilase 6 de Histona/metabolismo , Neoplasias Hepáticas/patologia , RNA Longo não Codificante/metabolismo , Proteínas Repressoras/metabolismo , Proteína 28 com Motivo Tripartido/metabolismo , Carcinoma Hepatocelular/metabolismo , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/metabolismo , Fatores de Transcrição/metabolismo
8.
BJOG ; 129 Suppl 2: 70-78, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36485065

RESUMO

OBJECTIVE: To explore the impact of the primary treatment sequence (primary debulking surgery, PDS, versus neoadjuvant chemotherapy and interval debulking surgery, NACT-IDS) on post-relapse survival (PRS) and recurrence characteristics of recurrent epithelial ovarian cancer (REOC). DESIGN: Real-world retrospective study. SETTING: Tertiary hospitals in China. POPULATION: A total of 853 patients with REOC at International Federation of Gynaecology and Obstetrics stages IIIC-IV from September 2007 to June 2020. Overall, 377 and 476 patients received NACT-IDS and PDS, respectively. METHODS: Propensity score-based inverse probability of treatment weighting (IPTW) was performed to balance the between-group differences. MAIN OUTCOME MEASURES: Clinicopathological factors related to PRS. RESULTS: The overall median PRS was 29.3 months (95% CI 27.0-31.5 months). Multivariate analysis before and after IPTW adjustment showed that NACT-IDS and residual R1/R2 disease were independent risk factors for PRS (p < 0.05). Patients with diffuse carcinomatosis and platinum-free interval (PFI) ≤ 12 months had a significantly worse PRS (p < 0.001). Logistic regression analysis revealed that NACT-IDS was an independent risk factor for diffuse carcinomatosis (OR 1.36, 95% CI 1.01-1.82, p = 0.040) and PFI ≤ 12 months (OR 1.59, 95% CI 1.08-2.35, p = 0.019). In IPTW analysis, NACT-IDS was still significantly associated with diffuse carcinomatosis (OR 1.29, 95% CI 1.05-1.58, p = 0.015) and PFI ≤ 12 months (OR 1.90, 95% CI 1.52-2.38, p < 0.001). CONCLUSIONS: The primary treatment sequence may affect the PRS of patients with REOC by altering the recurrence pattern and PFI duration.


Assuntos
Neoplasias Ovarianas , Humanos , Feminino , Carcinoma Epitelial do Ovário/patologia , Estudos Retrospectivos , Neoplasias Ovarianas/cirurgia , Neoplasias Ovarianas/tratamento farmacológico , Quimioterapia Adjuvante , Estadiamento de Neoplasias , Recidiva Local de Neoplasia/patologia , Procedimentos Cirúrgicos de Citorredução , Neoplasia Residual
9.
BJOG ; 129 Suppl 2: 60-69, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36485066

RESUMO

OBJECTIVE: To produce high-quality, real-world evidence for oncologists by collating scattered gynaecologic oncology (GO) medical records in China. DESIGN: Retrospective study. SETTING: The National Union of Real-world Gynaecological Oncology Research and Patient Management Platform (NUWA platform). SAMPLE: Patient-centred data pool. METHODS: The NUWA platform integrated inpatient/outpatient clinical, gene and follow-up data. Data of 11 456 patients with ovarian cancer (OC) were collected and processed using 91 345 electronic medical records. Structured and unstructured data were de-identified and re-collated into a patient-centred data pool using a predefined GO data model by technology-aided abstraction. MAIN OUTCOME MEASURES: Recent treatment pattern shifts towards precision medicine for OC in China. RESULTS: Thirteen first-tier hospitals across China participated in the NUWA platform up to 7 December 2021. In total, 3504 (30.59%) patients were followed up by a stand-alone patient management centre. The percentage of patients undergoing breast cancer gene (BRCA) mutation tests increased by approximately six-fold between 2017 and 2018. A similar trend was observed in the administration rate of poly(ADP-ribose) polymerase inhibitors as first-line treatment and second-line treatment after September 2018, when olaparib was approved for clinical use in China. CONCLUSION: The NUWA platform has great potential to facilitate clinical studies and support drug development, regulatory reviews and healthcare decision-making.


Assuntos
População do Leste Asiático , Neoplasias Ovarianas , Feminino , Humanos , Estudos Retrospectivos , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , China
10.
Sensors (Basel) ; 22(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35161558

RESUMO

Strain measurements are vital for monitoring the load-bearing capacity and safety of structures. A common approach is to affix strain gages onto structural surfaces. On the other hand, most aerospace, automotive, civil, and mechanical structures are painted and coated, often with many layers, prior to their deployment. There is an opportunity to design smart and multifunctional paints that can be directly pre-applied onto structural surfaces to serve as a sensing layer among their other layers of functional paints. Therefore, the objective of this study was to design a strain-sensitive paint that can be used for structural monitoring. Carbon nanotubes (CNT) were dispersed in paint by high-speed shear mixing, while paint thinner was employed for adjusting the formulation's viscosity and nanomaterial concentration. The study started with the design and fabrication of the CNT-based paint. Then, the nanocomposite paint's electromechanical properties and its sensitivity to applied strains were characterized. Third, the nanocomposite paint was spray-coated onto patterned substrates to form "Sensing Meshes" for distributed strain monitoring. An electrical resistance tomography (ERT) measurement strategy and algorithm were utilized for reconstructing the conductivity distribution of the Sensing Meshes, where the magnitude of conductivity (or resistivity) corresponded to the magnitude of strain, while strain directionality was determined based on the strut direction in the mesh.


Assuntos
Nanocompostos , Nanotubos de Carbono , Condutividade Elétrica , Pintura , Próteses e Implantes
11.
Hepatology ; 72(5): 1666-1681, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32083756

RESUMO

BACKGROUND AND AIMS: The nuclear factor kappa B (NF-κB) signaling pathway is important for linking inflammation and tumorigenesis. Here, we characterized an NF-κB signaling activation-induced long intergenic noncoding (LINC) RNA in hepatocellular carcinoma (HCC), LINC00665, that contributes to the enhanced cell proliferation of HCC cells both in vitro and in vivo. APPROACH AND RESULTS: LINC00665 physically interacts with the double-stranded RNA (dsRNA)-activated protein kinase (PKR), enhances its activation, and maintains its protein stability by blocking ubiquitin/proteasome-dependent degradation, resulting in a positive feedback regulation of NF-κB signaling in HCC cells. Notably, patients with HCC and higher LINC00665 have poorer outcomes in the clinic. CONCLUSIONS: Our findings indicate that LINC00665 is involved in the NF-κB signaling activation in HCC cells and that the inflammatory LINC00665/PKR/NF-κB loop plays important oncogenic roles in hepatic cancer progression and may be a potential therapeutic target.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , RNA Longo não Codificante/metabolismo , eIF-2 Quinase/genética , Animais , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Estudos de Coortes , Desmetilação do DNA , Conjuntos de Dados como Assunto , Retroalimentação Fisiológica , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Fígado/patologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Estabilidade Proteica , RNA Longo não Codificante/análise , RNA Longo não Codificante/genética , Transdução de Sinais/genética , Análise de Sobrevida , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto , eIF-2 Quinase/metabolismo
12.
Hepatology ; 72(2): 548-568, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31815296

RESUMO

BACKGROUND AND AIMS: Alternative splicing (AS) is a key step that increases the diversity and complexity of the cancer transcriptome. Recent evidence has highlighted that AS has an increasingly crucial role in cancer. Nonetheless, the mechanisms underlying AS and its dysregulation in hepatocellular carcinoma (HCC) remain elusive. Here, we report that the expression of RNA-binding protein p54nrb /non-POU domain-containing octamer-binding protein (NONO) is frequently increased in patients with HCC and is associated with poor outcomes. APPROACH AND RESULTS: Knockdown of NONO significantly abolished liver cancer cell proliferation, migration, and tumor formation. RNA-sequencing revealed that NONO regulates MYC box-dependent interacting protein 1 (or bridging integrator 1 [BIN1]; also known as amphiphysin 2 3P9) exon 12a splicing. In the normal liver, BIN1 generates a short isoform (BIN1-S) that acts as a tumor suppressor by inhibiting the binding of c-Myc to target gene promoters. In HCC, NONO is highly up-regulated and produces a long isoform (BIN1-L, which contains exon 12a) instead of BIN1-S. High levels of BIN1-L promote carcinogenesis by binding with the protein polo-like kinase 1 to enhance its stability through the prevention of ubiquitin/proteasome-dependent cullin 3 degradation. Further analysis revealed that NONO promotes BIN1 exon 12a inclusion through interaction with DExH-box helicase 9 (DHX9) and splicing factor proline and glutamine-rich (SFPQ). Notably, frequent coexpression of DHX9-NONO-SFPQ is observed in patients with HCC. CONCLUSIONS: Taken together, our findings identify the DHX9-NONO-SFPQ complex as a key regulator manipulating the oncogenic splicing switch of BIN1 and as a candidate therapeutic target in liver cancer.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Processamento Alternativo , Carcinogênese , Carcinoma Hepatocelular/genética , Proteínas de Ligação a DNA/fisiologia , Neoplasias Hepáticas/genética , Proteínas Nucleares/genética , Proteínas de Ligação a RNA/fisiologia , Proteínas Supressoras de Tumor/genética , Linhagem Celular Tumoral , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isoformas de Proteínas
13.
Hepatology ; 71(1): 259-274, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31173389

RESUMO

Hepatocellular carcinoma (HCC) is a highly lethal cancer and its underlying etiology remains understudied. The immense diversity and complexity of the cancer transcriptome hold the potential to yield tumor-specific transcripts (TSTs). Here, we showed that hundreds of TSTs are frequently expressed in HCC by an assembling spliced junction analysis of RNA sequencing raw data from approximately 1,000 normal and HCC tissues. Many of the TSTs were found to be unannotated and noncoding RNAs. We observed that intergenic TSTs are generated from transcription initiation sites frequently harboring long terminal repeat (LTR) elements. The strong presence of TSTs indicates significantly poor prognoses in HCC. Functional screening revealed a noncoding TST (termed TST1), which acted as a regulator of HCC cell proliferation and tumorigenesis. TST1 is generated from an LTR12C promoter regulated by DNA methylation and retinoic-acid-related drugs. Additionally, we observed that TSTs may be detected in the blood extracellular vesicles of patients with HCC. Conclusion: Our findings suggest an abundance of TSTs in HCC and their potential in clinical settings. The identification and characterization of TSTs may help toward the development of strategies for cancer diagnosis and treatment.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Transcriptoma , Regulação Neoplásica da Expressão Gênica , Humanos , RNA Neoplásico/análise
14.
Hepatology ; 69(1): 359-375, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30014619

RESUMO

Alternative splicing (AS) is assumed to be a pivotal determinant for the generation of diverse transcriptional variants in cancer. However, the comprehensive dysregulation of AS and the prospective biological and clinical relevance in hepatocellular carcinoma (HCC) remain obscure. Here, we identified and depicted the AS landscape in HCC by performing reference-based assembly of sequencing reads from over 600 RNA sequencing (RNA-seq) libraries. We detected various differentially spliced ASEs across patients covering not only protein-coding genes, but also considerable numbers of noncoding genes. Strikingly, alternative transcription initiation was found to frequently occur in HCC. These differential ASEs were highly related to "cancer hallmarks" and involved in metabolism-related pathways in particular. In addition, 243 differential ASEs were identified as risk predictors for HCC patient survival. The isoform switch of metabolism-related gene UGP2 (UDP-glucose pyrophosphorylase 2) might play an essential role in HCC. We further constructed regulatory networks between RNA-binding protein (RBP) genes and the corresponding ASEs. Further analysis demonstrated that the regulated networks were enriched in a variety of metabolism-related pathways. Conclusion: Differential ASEs are prevalent in HCC, where alternative transcription initiation was found to frequently occur. We found that genes having differential ASEs were significantly enriched in metabolism-related pathways. The expression variations, binding relations, and even mutations of RBP genes largely influenced differential ASEs in HCC.


Assuntos
Processamento Alternativo/fisiologia , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Transcriptoma/fisiologia , Perfilação da Expressão Gênica , Humanos , Células Tumorais Cultivadas
15.
FASEB J ; 33(6): 7213-7224, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30865837

RESUMO

MicroRNAs (miRNAs) crucially modulate fundamental biologic processes such as angiogenesis. In the present study, we focused on the molecular function of miRNA-370-3p (miR-370) in regulating the angiogenic activity of endothelial cells (ECs). Transfection with miR-370 mimic (miR-370m) significantly inhibited the sprouting of human dermal microvascular EC (HDMEC) and HUVEC spheroids and mouse aortic rings, whereas miR-370 inhibitor (miR-370i) promoted sprout formation. Additional in vitro assays demonstrated the pleiotropic inhibitory effects of miR-370m on HDMEC proliferation, migration, and tube formation. Moreover, Matrigel plugs containing miR-370m-transfected HDMECs exhibited a reduced microvessel density after implantation into CD1 nude mice when compared with controls. In contrast, miR-370i exerted proangiogenic effects. Mechanistic analyses revealed that miR-370 directly targets smoothened (SMO) and down-regulates bone morphogenetic protein (BMP)-2 expression in HDMECs. Accordingly, inhibition of SMO by cyclopamine reversed miR-370i-induced HDMEC proliferation and migration. In addition, BMP-2 treatment counteracted miR-370m-suppressed tube formation of HDMECs, whereas blockade of BMP-2 with neutralizing antibody significantly inhibited miR-370i-induced tube formation. Taken together, these novel findings indicate that miR-370 is a potent inhibitor of angiogenesis, which directly targets SMO and BMP-2.-Gu, Y., Becker, V., Zhao, Y., Menger, M. D., Laschke, M. W. miR-370 inhibits the angiogenic activity of endothelial cells by targeting smoothened (SMO) and bone morphogenetic protein (BMP)-2.


Assuntos
Proteína Morfogenética Óssea 2/fisiologia , Células Endoteliais/metabolismo , MicroRNAs/fisiologia , Neovascularização Fisiológica/genética , Receptor Smoothened/fisiologia , Animais , Aorta , Proteína Morfogenética Óssea 2/antagonistas & inibidores , Capilares/citologia , Divisão Celular , Movimento Celular , Células Cultivadas , Células Endoteliais/transplante , Fibroblastos , Células Endoteliais da Veia Umbilical Humana , Humanos , Queratinócitos , Masculino , Camundongos , Camundongos Nus , MicroRNAs/genética , Neovascularização Fisiológica/efeitos dos fármacos , Técnicas de Cultura de Órgãos , Osteoblastos , Interferência de RNA , RNA Interferente Pequeno/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Pele/irrigação sanguínea , Receptor Smoothened/antagonistas & inibidores , Receptor Smoothened/genética , Esferoides Celulares , Transfecção , Alcaloides de Veratrum/farmacologia
16.
Hepatology ; 67(1): 171-187, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28746790

RESUMO

Long noncoding RNAs can serve as oncogenes or tumor suppressors in human cancer; however, their biological functions and underlying mechanism in hepatocarcinogenesis are largely unknown. Here, we report a novel tumor suppressor long noncoding RNA on chromosome 8p12 (termed TSLNC8) that is frequently deleted and down-regulated in hepatocellular carcinoma (HCC) tissues. The loss of TSLNC8 is highly associated with the malignant features of HCC and serves as a prognostic indicator for HCC patients. TSLNC8 significantly suppresses the proliferation and metastasis of HCC cells in vitro and in vivo. TSLNC8 exerts its tumor suppressive activity by competitively interacting with transketolase and signal transducer and activator of transcription 3 (STAT3) and modulating the STAT3-Tyr705 and STAT3-Ser727 phosphorylation levels and STAT3 transcriptional activity, thus resulting in inactivation of the interleukin-6-STAT3 signaling pathway in HCC cells. CONCLUSION: TSLNC8 is a promising prognostic predictor for patients with HCC, and the TSLNC8-transketolase-STAT3 axis is a potential therapeutic target for HCC treatment. (Hepatology 2018;67:171-187).


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/patologia , Interleucina-6/metabolismo , Neoplasias Hepáticas/patologia , RNA Longo não Codificante/metabolismo , Fator de Transcrição STAT3/metabolismo , Análise de Variância , Biópsia por Agulha , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Receptor gp130 de Citocina/metabolismo , Regulação para Baixo , Genes Supressores de Tumor , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/metabolismo , Fosforilação , Projetos Piloto , Prognóstico , Modelos de Riscos Proporcionais , RNA Longo não Codificante/genética , Curva ROC , Fator de Transcrição STAT3/genética , Transdução de Sinais
17.
J Neurosci ; 36(50): 12586-12597, 2016 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-27974614

RESUMO

Hydrocephalus is a brain disorder derived from CSF accumulation due to defects in CSF clearance. Although dysfunctional apical cilia in the ependymal cell layer are causal to the onset of hydrocephalus, mechanisms underlying proper ependymal cell differentiation are largely unclear. SNX27 is a trafficking component required for normal brain function and was shown previously to suppress γ-secretase-dependent amyloid precursor protein and Notch cleavage. However, it was unclear how SNX27-dependent γ-secretase inhibition could contribute to brain development and pathophysiology. Here, we describe and characterize an Snx27-deleted mouse model for the ependymal layer defects of deciliation and hydrocephalus. SNX27 deficiency results in reductions in ependymal cells and cilia density, as well as severe postnatal hydrocephalus. Inhibition of Notch intracellular domain signaling with γ-secretase inhibitors reversed ependymal cells/cilia loss and dilation of lateral ventricles in Snx27-deficient mice, giving strong indication that Snx27 deletion triggers defects in ependymal layer formation and ciliogenesis through Notch hyperactivation. Together, these results suggest that SNX27 is essential for ependymal cell differentiation and ciliogenesis, and its deletion can promote hydrocephalus pathogenesis. SIGNIFICANCE STATEMENT: Down's syndrome (DS) in humans and mouse models has been shown previously to confer a high risk for the development of pathological hydrocephalus. Because we have previously described SNX27 as a component that is consistently downregulated in DS, we present here a robust Snx27-deleted mouse model that produces hydrocephalus and associated ciliary defects with complete penetrance. In addition, we find that γ-secretase/Notch modulation may be a candidate drug target in SNX27-associated hydrocephalus such as that observed in DS. Based on these findings, we anticipate that future study will determine whether modulation of a SNX27/Notch/γ-secretase pathway can also be of therapeutic interest to congenital hydrocephalus.


Assuntos
Diferenciação Celular/fisiologia , Cílios/fisiologia , Epêndima/patologia , Hidrocefalia/genética , Hidrocefalia/patologia , Nexinas de Classificação/fisiologia , Junções Aderentes/patologia , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Animais , Cílios/patologia , Epêndima/citologia , Fibroblastos/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Cultura Primária de Células , Receptores Notch/metabolismo , Nexinas de Classificação/genética
18.
J Neurosci ; 36(30): 7996-8011, 2016 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-27466343

RESUMO

UNLABELLED: Proteolytic generation of amyloidogenic amyloid ß (Aß) fragments from the amyloid precursor protein (APP) significantly contributes to Alzheimer's disease (AD). Although amyloidogenic APP proteolysis can be affected by trafficking through genetically associated AD components such as SORLA, how SORLA functionally interacts with other trafficking components is yet unclear. Here, we report that SNX27, an endosomal trafficking/recycling factor and a negative regulator of the γ-secretase complex, binds to the SORLA cytosolic tail to form a ternary complex with APP. SNX27 enhances cell surface SORLA and APP levels in human cell lines and mouse primary neurons, and depletion of SNX27 or SORLA reduces APP endosome-to-cell surface recycling kinetics. SNX27 overexpression enhances the generation of cell surface APP cleavage products such as soluble alpha-APP C-terminal fragment (CTFα) in a SORLA-dependent manner. SORLA-mediated Aß reduction is attenuated by downregulation of SNX27. This indicates that an SNX27/SORLA complex functionally interacts to limit APP distribution to amyloidogenic compartments, forming a non-amyloidogenic shunt to promote APP recycling to the cell surface. SIGNIFICANCE STATEMENT: Many genes have been identified as risk factors for Alzheimer's disease (AD), and a large proportion of these genes function to limit production or toxicity of the AD-associated amyloid ß (Aß) peptide. Whether and how these genes precisely operate to limit AD onset remains an important question. We identify binding and trafficking interactions between two of these factors, SORLA and SNX27, and demonstrate that SNX27 can direct trafficking of SORLA and the Aß precursor APP to the cell surface to limit the production of Aß. Diversion APP to the cell surface through modulation of this molecular complex may represent a complimentary strategy for future development in AD treatment.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Amiloide/biossíntese , Proteínas de Membrana Transportadoras/metabolismo , Neurônios/metabolismo , Receptores de LDL/metabolismo , Nexinas de Classificação/metabolismo , Frações Subcelulares/metabolismo , Proteínas Amiloidogênicas/metabolismo , Animais , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Feminino , Regulação da Expressão Gênica , Células HEK293 , Humanos , Camundongos , Neurônios/citologia , Ligação Proteica , Transporte Proteico
20.
BMC Cancer ; 17(1): 648, 2017 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-28903735

RESUMO

BACKGROUND: FOXP3 has been discovered to be expressed in tumor cells and participate in the regulation of tumor behavior. Herein, we investigated the clinical relevance and biological significance of FOXP3 expression in human hepatocellular carcinoma (HCC). METHODS: Expression profile of FOXP3 was analyzed using real-time RT-PCR, western blotting and immunofluorescence on HCC cell lines, and immunostaing of a tissue microarray containing of 240 primary HCC samples. The potential regulatory roles of FOXP3 were dissected by an integrated approach, combining biochemical assays, analysis of patient survival, genetic manipulation of HCC cell lines, mouse xenograft tumor models and chromatin immunoprecipitation (ChIP) sequencing. RESULTS: FOXP3 was constitutively expressed in HCC cells with the existence of splice variants (especially exon 3 and 4 deleted, Δ3,4-FOXP3). High expression of FOXP3 significantly correlated with low serum α-fetoprotein (AFP) level, absence of vascular invasion and early TNM stage. Survival analyses revealed that increased FOXP3 expression was significantly associated with better survival and reduced recurrence, and served as an independent prognosticator for HCC patients. Furthermore, FOXP3 could potently suppress the proliferation and invasion of HCC cells in vitro and reduce tumor growth in vivo. However, Δ3,4-FOXP3 showed a significant reduction in the tumor-inhibiting effect. The inhibition of FOXP3 on HCC aggressiveness was acted probably by enhancing the TGF-ß/Smad2/3 signaling pathway. CONCLUSION: Our findings suggest that FOXP3 suppresses tumor progression in HCC via TGF-ß/Smad2/3 signaling pathway, highlighting the role of FOXP3 as a prognostic factor and novel target for an optimal therapy against this fatal malignancy.


Assuntos
Carcinoma Hepatocelular/genética , Fatores de Transcrição Forkhead/genética , Neoplasias Hepáticas/genética , Fator de Crescimento Transformador beta/genética , Idoso , Animais , Carcinoma Hepatocelular/patologia , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Transdução de Sinais/genética , Proteína Smad2/genética , Proteína Smad3/genética , Proteínas Supressoras de Tumor/genética
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