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1.
Cell Death Differ ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778217

RESUMO

Deregulated glucose metabolism termed the "Warburg effect" is a fundamental feature of cancers, including the colorectal cancer. This is typically characterized with an increased rate of glycolysis, and a concomitant reduced rate of the tricarboxylic acid (TCA) cycle metabolism as compared to the normal cells. How the TCA cycle is manipulated in cancer cells remains unknown. Here, we show that O-linked N-acetylglucosamine (O-GlcNAc) regulates the TCA cycle in colorectal cancer cells. Depletion of OGT, the sole transferase of O-GlcNAc, significantly increases the TCA cycle metabolism in colorectal cancer cells. Mechanistically, OGT-catalyzed O-GlcNAc modification of c-Myc at serine 415 (S415) increases c-Myc stability, which transcriptionally upregulates the expression of pyruvate dehydrogenase kinase 2 (PDK2). PDK2 phosphorylates pyruvate dehydrogenase (PDH) to inhibit the activity of mitochondrial pyruvate dehydrogenase complex, which reduces mitochondrial pyruvate metabolism, suppresses reactive oxygen species production, and promotes xenograft tumor growth. Furthermore, c-Myc S415 glycosylation levels positively correlate with PDK2 expression levels in clinical colorectal tumor tissues. This study highlights the OGT-c-Myc-PDK2 axis as a key mechanism linking oncoprotein activation with deregulated glucose metabolism in colorectal cancer.

2.
Lett Appl Microbiol ; 77(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38414284

RESUMO

The most toxic of the ochratoxins is ochratoxin A (OTA), which is primarily produced by species of Aspergillus and Penicillium that can be found in maize, wheat, coffee, red wine, and various grains. OTA induces immunotoxicity, nephrotoxicity, hepatotoxicity, teratogenicity, and carcinogenicity in both animals and humans. Thus, there is a need to identify mycotoxin detoxification agents that can effectively decontaminate OTA. Seeds of basil (Ocimum basilicum L.), chan (Hyptis suaveolens L.), and chia (Salvia hispanica L.) are functional foods capable of eliminating harmful substances. Despite this potential, the impact of these seeds on OTA detoxification remains unclear. This study reveals that milled basil, chan, and chia seeds adsorb significant levels of OTA, with chia demonstrating the highest adsorption capacity, followed by chan and basil seeds showing the least efficiency. Furthermore, milled basil, chan, and chia seeds effectively reduced OTA residues in artificial gastric and intestinal fluids, where they achieved up to 93% OTA adsorption in the former. In addition, these milled seeds were able to remove OTAs from canned, drip, and instant coffee. This study is the first to report the OTA elimination potential of basil, chan, and chia seeds.


Assuntos
Ocratoxinas , Ocimum basilicum , Humanos , Animais , Ocratoxinas/análise , Café/química , Sementes/química
3.
J Cancer Res Clin Oncol ; 150(2): 103, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38400862

RESUMO

PURPOSE: At present, dysfunctional CD8+ T-cells in the nasopharyngeal carcinoma (NPC) tumor immune microenvironment (TIME) have caused unsatisfactory immunotherapeutic effects, such as a low response rate of anti-PD-L1 therapy. Therefore, there is an urgent need to identify reliable markers capable of accurately predicting immunotherapy efficacy. METHODS: Utilizing various algorithms for immune-infiltration evaluation, we explored the role of EIF3C in the TIME. We next found the influence of EIF3C expression on NPC based on functional analyses and RNA sequencing. By performing correlation and univariate Cox analyses of CD8+ Tcell markers from scRNA-seq data, we identified four signatures, which were then used in conjunction with the lasso algorithm to determine corresponding coefficients in the resulting EIF3C-related CD8+ T-cell signature (ETS). We subsequently evaluated the prognostic value of ETS using univariate and multivariate Cox regression analyses, Kaplan-Meier curves, and the area under the receiver operating characteristic curve (AUROC). RESULTS: Our results demonstrate a significant relationship between low expression of EIF3C and high levels of CD8+ T-cell infiltration in the TIME, as well as a correlation between EIF3C expression and progression of NPC. Based on the expression levels of four EIF3C-related CD8+ T-cell marker genes, we constructed the ETS predictive model for NPC prognosis, which demonstrated success in validation. Notably, our model can also serve as an accurate indicator for detecting immunotherapy response. CONCLUSION: Our findings suggest that EIF3C plays a significant role in NPC progression and immune modulation, particularly in CD8+ T-cell infiltration. Furthermore, the ETS model holds promise as both a prognostic predictor for NPC patients and a tool for adjusting individualized immunotherapy strategies.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/terapia , Prognóstico , Imunoterapia , Neoplasias Nasofaríngeas/terapia , Microambiente Tumoral
4.
Mol Pharm ; 21(1): 102-112, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37994899

RESUMO

O-linked-N-acetylglucosaminylation (O-GlcNAcylation) plays a key role in hepatocellular carcinoma (HCC) development, and the inhibition of O-GlcNAcylation has therapeutic potential. To decrease the systemic adverse events and increase targeting, we used sialic acid (SA)-decorated liposomes loaded with OSMI-1, an inhibitor of the O-GlcNAcylation, to further improve the anti-HCC effect. Fifty pairs of HCC tissue samples and the cancer genome atlas database were used to analyze the expression of O-GlcNAc transferase (OGT) and its effects on prognosis and immune cell infiltration. OSMI-1 cells were treated with SA and liposomes. Western blotting, immunofluorescence, cell proliferation assay, flow cytometry, enzyme-linked immunosorbent assay, immunohistochemistry, and tumorigenicity assays were used to investigate the antitumor effect of SA-modified OSMI-1 liposomes in vitro and in vivo. OGT was highly expressed in HCC tissues, negatively correlated with the degree of tumor infiltration of CD8+ and CD4+T cells and prognosis, and positively correlated with the degree of Treg cell infiltration. SA-modified OSMI-1 liposome (OSMI-1-SAL) was synthesized with stable hydrodynamic size distribution. Both in vitro and in vivo, OSMI-1-SAL exhibited satisfactory biosafety and rapid uptake by HCC cells. Compared to free OSMI-1, OSMI-1-SAL had a stronger capacity for suppressing the proliferation and promoting the apoptosis of HCC cells. Moreover, OSMI-1-SAL effectively inhibited tumor initiation and development in mice. OSMI-1-SAL also promoted the release of damage-associated molecular patterns, including anticalreticulin, high-mobility-group protein B1, and adenosine triphosphate, from HCC cells and further promoted the activation and proliferation of the CD8+ and CD4+T cells. In conclusion, the OSMI-1-SAL synthesized in this study can target HCC cells, inhibit tumor proliferation, induce tumor immunogenic cell death, enhance tumor immunogenicity, and promote antitumor immune responses, which has the potential for clinical application in the future.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Camundongos , Animais , Carcinoma Hepatocelular/genética , Lipossomos/farmacologia , Neoplasias Hepáticas/metabolismo , Ácido N-Acetilneuramínico , Proliferação de Células
5.
Antioxidants (Basel) ; 12(9)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37760042

RESUMO

Ferroptosis is an iron-dependent and lipid peroxidation-driven cell death cascade, occurring when there is an imbalance of redox homeostasis in the cell. Nuclear factor erythroid 2-related factor 2 (NFE2L2, also known as NRF2) is key for cellular antioxidant responses, which promotes downstream genes transcription by binding to their antioxidant response elements (AREs). Numerous studies suggest that NRF2 assumes an extremely important role in the regulation of ferroptosis, for its various functions in iron, lipid, and amino acid metabolism, and so on. Many pathological states are relevant to ferroptosis. Abnormal suppression of ferroptosis is found in many cases of cancer, promoting their progression and metastasis. While during tissue damages, ferroptosis is recurrently promoted, resulting in a large number of cell deaths and even dysfunctions of the corresponding organs. Therefore, targeting NRF2-related signaling pathways, to induce or inhibit ferroptosis, has become a great potential therapy for combating cancers, as well as preventing neurodegenerative and ischemic diseases. In this review, a brief overview of the research process of ferroptosis over the past decade will be presented. In particular, the mechanisms of ferroptosis and a focus on the regulation of ferroptosis by NRF2 will be discussed. Finally, the review will briefly list some clinical applications of targeting the NRF2 signaling pathway in the treatment of diseases.

7.
Proc Natl Acad Sci U S A ; 120(13): e2216796120, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36943877

RESUMO

Programmed-death ligand 1 (PD-L1) and its receptor programmed cell death 1 (PD-1) mediate T cell-dependent immunity against tumors. The abundance of cell surface PD-L1 is a key determinant of the efficacy of immune checkpoint blockade therapy targeting PD-L1. However, the regulation of cell surface PD-L1 is still poorly understood. Here, we show that lysosomal degradation of PD-L1 is regulated by O-linked N-acetylglucosamine (O-GlcNAc) during the intracellular trafficking pathway. O-GlcNAc modifies the hepatocyte growth factor-regulated tyrosine kinase substrate (HGS), a key component of the endosomal sorting machinery, and subsequently inhibits its interaction with intracellular PD-L1, leading to impaired lysosomal degradation of PD-L1. O-GlcNAc inhibition activates T cell-mediated antitumor immunity in vitro and in immune-competent mice in a manner dependent on HGS glycosylation. Combination of O-GlcNAc inhibition with PD-L1 antibody synergistically promotes antitumor immune response. We also designed a competitive peptide inhibitor of HGS glycosylation that decreases PD-L1 expression and enhances T cell-mediated immunity against tumor cells. Collectively, our study reveals a link between O-GlcNAc and tumor immune evasion, and suggests strategies for improving PD-L1-mediated immune checkpoint blockade therapy.


Assuntos
Antígeno B7-H1 , Evasão Tumoral , Animais , Camundongos , Antígeno B7-H1/metabolismo , Inibidores de Checkpoint Imunológico/metabolismo , Lisossomos/metabolismo , Linhagem Celular Tumoral
8.
Proc Natl Acad Sci U S A ; 119(10): e2107453119, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35239437

RESUMO

SignificanceEpidermal growth factor receptor (EGFR) is one of the most important membrane receptors that transduce growth signals into cells to sustain cell growth, proliferation, and survival. EGFR signal termination is initiated by EGFR internalization, followed by trafficking through endosomes, and degradation in lysosomes. How this process is regulated is still poorly understood. Here, we show that hepatocyte growth factor regulated tyrosine kinase substrate (HGS), a key protein in the EGFR trafficking pathway, is dynamically modified by a single sugar N-acetylglucosamine. This modification inhibits EGFR trafficking from endosomes to lysosomes, leading to the accumulation of EGFR and prolonged signaling. This study provides an important insight into diseases with aberrant growth factor signaling, such as cancer, obesity, and diabetes.


Assuntos
Endossomos/metabolismo , Lisossomos/metabolismo , Transdução de Sinais , Acilação/genética , Endossomos/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Células Hep G2 , Humanos , Lisossomos/genética , Transporte Proteico/genética
9.
Hepatobiliary Pancreat Dis Int ; 21(1): 41-49, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34600815

RESUMO

BACKGROUND: Accumulating data have suggested that long non-coding RNAs (lncRNAs) play important roles in regulating tumor cell growth. This study was designed to investigate the role of SNHG16 in hepatocellular carcinoma (HCC). METHODS: SNHG16 expression was detected with real-time polymerase chain reaction (PCR). The cutoff value of SNHG16 for tumor-free survival (TFS) was determined with receiver operating characteristic curve analysis. Small interfering RNA was used to inhibit the expression of SNHG16 in HCC cell lines. The biologic behavior of HCC cell was determined with cell viability assay and Transwell assay in vitro. The potential predictive value of SNHG16 on prognosis was analyzed by Kaplan-Meier curves and Cox proportional hazards regression model. RESULTS: SNHG16 expression was upregulated in tumor tissues and HCC cell lines. High expression of SNHG16 was associated with tumor recurrence and poor prognosis after surgery. Multivariate analysis revealed that SNHG16 was an independent prognostic factor for poor recurrence-free survival. Moreover, inhibition of SNHG16 in HepG2, Hep3B, and BEL-7402 cells significantly reduced cell invasiveness and proliferation. Mechanistic analyses indicated that the ECM-receptor interaction pathway was remarkably activated by SNHG16. CONCLUSIONS: SNHG16 might be a promising biomarker for predicting tumor recurrence in HCC patients after surgery and a potential therapeutic target for HCC.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Recidiva Local de Neoplasia/genética , RNA Longo não Codificante/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Superfície Celular
10.
Cells ; 12(1)2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36611819

RESUMO

Metabolic reprogramming, such as alterations in glutamine metabolism or glycolysis, is the hallmark of hepatocellular carcinoma (HCC). However, the underlying mechanisms are still incompletely elucidated. Previous studies have identified that methyltransferase SET and MYND domain-containing protein 2(SMYD2) is responsible for the pathogenesis of numerous types of cancer. Here, we innovatively uncover how SMYD2 regulates glutamine metabolism in HCC cells and promotes HCC progression. We identified that SMYD2 expression is upregulated in HCC tissues, which correlates with unfavorable clinical outcomes. Our in vitro and in vivo results showed that the depletion of SMYD2 inhibits HCC cell growth. Mechanistically, c-Myc methylation by SMYD2 increases its protein stability through the ubiquitin-proteasome system. We showed SMYD2 depletion destabilized c-Myc protein by increasing the conjugated K48-linked polyubiquitin chain. SMYD2 increased c-Myc expression and further upregulated glutaminase1 (GLS1), a crucial enzyme that catalyzes the conversion of glutamine to glutamic acid, in HCC cells. GLS1 plays an important role in SMYD2-mediated HCC progression and glutamine metabolism regulation. The knockdown of SMYD2 inhibited glutamine metabolism in HCC cells and overcame their chemoresistance to sorafenib. Collectively, our findings demonstrated a novel mechanism of how SMYD2 promotes HCC progression by regulating glutamine metabolism through the c-Myc/GLS1signaling, implicating the therapeutic potential of targeting SMYD2 in HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Glutamina/metabolismo , Neoplasias Hepáticas/patologia , Sorafenibe/uso terapêutico , Histona-Lisina N-Metiltransferase/metabolismo
11.
Angew Chem Int Ed Engl ; 60(50): 26128-26135, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34590401

RESUMO

O-linked N-acetylglucosamine (O-GlcNAcylation) is a ubiquitous post-translational modification of proteins that is essential for cell function. Perturbation of O-GlcNAcylation leads to altered cell-cycle progression and DNA damage response. However, the underlying mechanisms are poorly understood. Here, we develop a highly sensitive one-step enzymatic strategy for capture and profiling O-GlcNAcylated proteins in cells. Using this strategy, we discover that flap endonuclease 1 (FEN1), an essential enzyme in DNA synthesis, is a novel substrate for O-GlcNAcylation. FEN1 O-GlcNAcylation is dynamically regulated during the cell cycle. O-GlcNAcylation at the serine 352 of FEN1 disrupts its interaction with Proliferating Cell Nuclear Antigen (PCNA) at the replication foci, and leads to altered cell cycle, defects in DNA replication, accumulation of DNA damage, and enhanced sensitivity to DNA damage agents. Thus, our study provides a sensitive method for profiling O-GlcNAcylated proteins, and reveals an unknown mechanism of O-GlcNAcylation in regulating cell cycle progression and DNA damage response.


Assuntos
Acetilglucosamina/metabolismo , DNA/metabolismo , Endonucleases Flap/metabolismo , Acetilglucosamina/química , Ciclo Celular , DNA/química , Dano ao DNA , Endonucleases Flap/química , Glicosilação , Humanos
12.
Ann Transl Med ; 8(21): 1365, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33313110

RESUMO

BACKGROUND: Previous data have confirmed that disordered long non-coding ribonucleic acid (lncRNA) expression is evident in many cancers and is correlated with tumor progression. The present study aimed to investigate the function of long non-coding RNA00844 (LINC00844) in hepatocellular carcinoma (HCC). METHODS: The expression levels of target genes were detected with real-time polymerase chain reaction (PCR) and western blotting. The biologic function of HCC cells was determined with cell viability assay, colony formation assay, cell cycle analysis, apoptosis detection, and Transwell migration assay in vitro. Tumorigenesis was performed with cell injection in vivo. The relationship between LINC00844 and survival outcomes was determined with the Cox proportional hazards model. A RNA precipitation assay was conducted to reveal the types of LINC00844 that potentially bind with proteins. RESULTS: LINC00844 was found to be significantly decreased in HCC tissue and was correlated with poor tumor characteristics, such as portal vein invasion, high α-fetoprotein (AFP), and a high rate of tumor recurrence. Exotic LINC00844 expression in HCC cell lines significantly suppressed proliferation and migration, as well as invasiveness, whereas LINC00844 deletion had the opposite effect. LINC00844 overexpression significantly inhibited HCC tumorigenesis in vivo. Mechanistic analyses indicated that the mitogen-activated protein kinase (MAPK) signaling pathway was remarkably inactivated by LINC00844. Furthermore, the immunoprecipitation assay verified that LINC00844 can bind to zinc-alpha-2-glycoprotein (AZGP1) and interfere with its translocation. LINC00844 can also promote AZGP1 expression, leading to the suppression of the transforming growth factor-ß1 (TGF-ß1)-extracellular signal-regulated kinase (ERK) pathway. CONCLUSIONS: LINC00844 is a novel anti-oncogene in the development of HCC and a potentially promising therapeutic target in HCC.

13.
Technol Cancer Res Treat ; 19: 1533033820979703, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33308041

RESUMO

BACKGROUND: Novel immunotherapy is one of the options for advanced biliary tract cancer (BTC) patients who are traditionally intolerant to chemotherapy. However, clinical evidence for single immunotherapy with pembrolizumab or nivolumab is limited. The present study assessed the safety and efficiency of the anti-PD-1 antibody, camrelizumab, as monotherapy in patients with unresectable or recurrent BTC. METHODS: A retrospective evaluation was conducted among 4 patients with BTC, including 2 with intrahepatic cholangiocellular carcinoma (ICC), one with extrahepatic bile duct cancer, and one with gallbladder cancer. The patients with unresectable or recurrent BTC were refractory or intolerant to gemcitabine plus cisplatin treatment regimens and received at least one intravenous dose (3 mg/kg) of camrelizumab monotherapy every 3 weeks. Gene sequencing analysis was also performed for biomarker screening. Patient reaction was evaluated according to modified response evaluation criteria in solid tumor (RECIST) version 1.1, progression-free survival (PFS), and toxicity. RESULTS: In this cohort, 1 patient with recurrent ICC had a positive response to treatment, with a substantial tumor size reduction in liver and lung metastases verified using a radiological test after receiving 3 cycles of camrelizumab. The PFS was 4.9 months. The remaining 3 patients showed no response to treatment and experienced disease progression. RNA sequence analysis didn't found high expression on genes that related to PD-L1, microsatellite instability, tumor mutation burden, and DNA mismatch repair in these patients. Grade 3 treatment-related adverse event was observed in 1 patient. CONCLUSIONS: Anti-PD-1 antibody camrelizumab had a manageable safety profile in patients with advanced BTC. This initial assessment of camrelizumab monotherapy provides effective evidence for patients with refractory BTC in biomarker-unselected patients.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Neoplasias do Sistema Biliar/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Neoplasias do Sistema Biliar/diagnóstico , Neoplasias do Sistema Biliar/etiologia , Biomarcadores Tumorais , Feminino , Humanos , Inibidores de Checkpoint Imunológico/administração & dosagem , Inibidores de Checkpoint Imunológico/efeitos adversos , Masculino , Pessoa de Meia-Idade , Prognóstico , Tomografia Computadorizada por Raios X , Resultado do Tratamento
14.
Hepatobiliary Pancreat Dis Int ; 19(3): 252-257, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32205038

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is closely associated with obesity. However, this association could be influenced by the coexisting metabolic abnormalities. This study aimed to investigate the role of obesity and metabolic abnormalities in NAFLD among elderly Chinese. METHODS: A cross-sectional study was performed among elderly residents who took their annual health checkups during 2016 in Keqiao District, Shaoxing, China. RESULTS: A total of 3359 elderly adults were retrospectively included in this study. The overall prevalence of NAFLD was 28.7%. The prevalence of NAFLD were 7.14%, 27.92%, 34.80%, and 61.02% in participants with metabolically healthy normal weight (MHNW), metabolically abnormal normal weight (MANW), metabolically healthy obese (MHO), and metabolically abnormal obese (MAO), respectively. NAFLD patients in MHO group had more unfavorable metabolic profiles than those in MHNW group. Logistic regression analysis showed that sex, body mass index (BMI), fasting blood glucose, and serum uric acid were the risk factors of NAFLD. CONCLUSIONS: Both obesity and metabolic health were significantly associated with NAFLD in elderly Chinese. Screening for obesity and other metabolic abnormalities should be routinely performed for early risk stratification of NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Obesidade/sangue , Obesidade/epidemiologia , Idoso , Glicemia/metabolismo , Pressão Sanguínea , Índice de Massa Corporal , China/epidemiologia , Colesterol/sangue , Estudos Transversais , Jejum , Feminino , Humanos , Hipertrigliceridemia/sangue , Hipertrigliceridemia/epidemiologia , Peso Corporal Ideal , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores Sexuais , Ácido Úrico/sangue , Circunferência da Cintura
15.
Cancer Cell Int ; 19: 179, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31337986

RESUMO

BACKGROUND: Multi-drug resistance is the major cause of chemotherapy failure in hepatocellular carcinoma (HCC). YAP, a critical effector of the Hippo pathway, has been shown to contribute to the progression, metastasis and invasion of cancers. However, the potential role of YAP in mediating drug resistance remains obscure. METHODS: RT-qPCR and western blot were used to assess YAP expression in HCC cell lines. CCK-8 assays, flow cytometry, a xenograft tumour model, immunochemistry and GFP-mRFP-LC3 fusion proteins were utilized to evaluate the effect of YAP on multi-drug resistance, intracellular ROS production and the autophagy of HCC cells in vitro and in vivo. Autophagy inhibitor and rescue experiments were carried out to elucidate the mechanism by which YAP promotes chemoresistance in HCC cells. RESULTS: We found that BEL/FU, a typical HCC cell line with chemoresistance, exhibited overexpression of YAP. Moreover, the inhibition of YAP by shRNA or verteporfin conferred the sensitivity of BEL/FU cells to chemotherapeutic agents through autophagy-related cell death in vitro and in vivo. Mechanistically, YAP silencing significantly enhanced autophagic flux by increasing RAC1-driven ROS, which contributed to the inactivation of mTOR in HCC cells. In addition, the antagonist of autophagy reversed the enhanced effect of YAP silencing on cell death under treatment with chemotherapeutic agents. CONCLUSION: Our findings suggested that YAP upregulation endowed HCC cells with multi-drug resistance via the RAC1-ROS-mTOR pathway, resulting in the repression of autophagy-related cell death. The blockade of YAP may serve as a promising novel therapeutic strategy for overcoming chemoresistance in HCC.

16.
Hepatobiliary Pancreat Dis Int ; 18(3): 223-227, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31056483

RESUMO

BACKGROUND: Lower mean platelet volume (MPV) is an indicator of platelet activity in the setting of tumor development. This study was to assess the relationship between preoperative MPV and survival outcomes of patients with hepatocellular carcinoma (HCC) following liver transplantation (LT). METHODS: The demographic and clinical characteristics of 304 HCC patients following LT were retrieved from an LT database. All the patients were divided into the normal and lower MPV groups according to the median MPV. The factors were first analyzed using a Kaplan-Meier survival analysis, then the factors with P < 0.10 were selected for multivariate Cox regression analysis and were used to define the independent risk factors for poor prognosis. RESULTS: The 1-, 3-, and 5-year tumor free survival was 95.34%, 74.67% and 69.29% in the normal MPV group, respectively, and 95.40%, 59.97% and 42.94% in the lower MPV group, respectively (P < 0.01). No significant difference was observed in post-LT complications between the normal and lower MPV groups. Portal vein tumor thrombosis (PVTT) [hazard ratio (HR = 2.24; 95% confidence interval: 1.46-3.43; P < 0.01) and lower MPV (HR = 1.58; 95% confidence interval: 1.05-2.36; P = 0.03) were identified as independent prognostic risk factors for recipient survival. CONCLUSION: Preoperative lower MPV is a risk indicator of HCC patients survival outcomes after LT.


Assuntos
Plaquetas , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/efeitos adversos , Volume Plaquetário Médio , Recidiva Local de Neoplasia , Adulto , Idoso , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Bases de Dados Factuais , Feminino , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
17.
Acta Biomater ; 86: 363-372, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30660006

RESUMO

It is well known that stealth coating effectively extends the circulation lifetime of nanomaterials in blood, which favors systemic delivery but also limits their cellular internalization and in turn prevents efficient tumor-targeting and accumulation. In this study, we address this dilemma by developing an enzyme-responsive zwitterionic stealth peptide coating capable of responding to matrix metalloproteinase-9 (MMP-9) which is overexpressed in tumor microenvironment. The peptide consists of a cell-penetrating Tat sequence, an MMP-9 cleavable sequence, and a zwitterionic antifouling sequence. Using this coating to protect photothermal gold nanorods (AuNRs), we found that responsive AuNRs showed both satisfactory systemic circulation lifetime and significantly enhanced cellular uptake in tumors, resulting in clearly improved photothermal therapeutic efficacy in mouse models. These results suggest that multifunctional peptide coated AuNRs sensitive to MMP-9 are promising nanomaterials, conferring both extended systemic circulation and enhanced tumor tissue accumulation, for more specific and efficient tumor therapy. STATEMENT OF SIGNIFICANCE: It is well known that stealth coating effectively extends the circulation lifetime of nanomaterials in blood, which favors systemic delivery but also limits their cellular internalization and in turn prevents efficient tumor-targeting and accumulation. In this study, we address this dilemma by developing an enzyme-responsive zwitterionic stealth peptide coating capable of responding to matrix metalloproteinase-9 (MMP-9) which is overexpressed in tumor microenvironment. The peptide consists of a cell-penetrating Tat sequence, an MMP-9 cleavable sequence, and a zwitterionic antifouling sequence. Using this coating to protect photothermal gold nanorods (AuNRs), we found that responsive AuNRs showed both satisfactory systemic circulation lifetime and significantly enhanced cellular uptake in tumors, resulting in clearly improved photothermal therapeutic efficacy in mouse models.


Assuntos
Materiais Revestidos Biocompatíveis/química , Ouro/química , Hipertermia Induzida , Metaloproteinase 9 da Matriz/metabolismo , Nanotubos/química , Neoplasias/terapia , Peptídeos/química , Fototerapia , Animais , Circulação Sanguínea , Morte Celular , Células Hep G2 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Nanotubos/ultraestrutura , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Eletricidade Estática
18.
BMB Rep ; 51(12): 630-635, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30293547

RESUMO

C-X-C motif chemokine ligand 2 (CXCL2) is a small secreted protein that exhibits a structure similar to the proangiogenic subgroup of the CXC chemokine family. Recently, accumulating evidence suggests that chemokines play a pivotal role in cancer progression and carcinogenesis. We examined the expression levels of 7 types of ELR+ CXCLs messenger RNA (mRNA) in 264 clinical samples. We found that CXCL2 expression was stably down-regulated in 94% of hepatocellular carcinoma (HCC) specimens compared with paired adjacent normal liver tissues and some HCC cell lines. Moreover, CXCL2 overexpression profoundly attenuated HCC cell proliferation and growth and induced apoptosis in vitro. In animal studies, we found that overexpressing CXCL2 by lentivirus also apparently inhibited the size and weight of subcutaneous tumours in nude mice. Furthermore, we demonstrated that CXCL2 induced HCC cell apoptosis via both nuclear and mitochondrial apoptosis pathways. Our results indicate that CXCL2 negatively regulates the cell cycle in HCC cells via the ERK1/2 signalling pathway. These results provide new insights into HCC and may ultimately lead to the discovery of innovative therapeutic approaches of HCC. [BMB Reports 2018; 51(12): 630-635].


Assuntos
Apoptose , Carcinoma Hepatocelular/patologia , Proliferação de Células , Quimiocina CXCL2/metabolismo , Neoplasias Hepáticas/patologia , Animais , Carcinoma Hepatocelular/metabolismo , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Quimiocina CXCL2/antagonistas & inibidores , Quimiocina CXCL2/genética , Regulação para Baixo , Feminino , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transdução de Sinais
19.
Ann Clin Lab Sci ; 48(3): 328-332, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29970436

RESUMO

BACKGROUND: CD16+ monocytes have recently shown the ability to inhibit the proliferation of CD4+CD25+Foxp3+ T cells (Tregs). The inhibitory role of Tregs in acute rejection has been described in patients with liver transplantation. However, the role of CD16+ monocytes in the development of allograft rejection after liver transplantation remains unknown. METHODS: Forty-five liver transplant recipients, including 25 acute rejection diagnosed by liver biopsy and clinical symptoms and 20 stable allograft liver function recipients, were collected from January 2007 to September 2015 at our hospitals. To assay the frequencies of CD16+ monocytes and Tregs in blood samples, flow cytometry was performed. RESULTS: Compared with the stable allograft liver function recipients, a significant increase in CD16+ monocytes (19.45±5.25% vs 7.17±1.69%, P<0.001) and decreased Tregs (1.74±0.59% vs 5.53±2.18%, P<0.001) was observed among recipients with acute rejection. CD16+ monocytes were positively correlated with RAI (rejection activity index) (R2=0.84, P<0.001), but negatively correlated with the frequency of Tregs (R2=0.86, P<0.001). CONCLUSIONS: Based on our data, we concluded that CD16+ monocytes might be responsible for the development of acute allograft rejection after liver transplantation, which may be associated with inhibition of Treg cells.


Assuntos
Rejeição de Enxerto/diagnóstico , Hepatopatias/cirurgia , Transplante de Fígado/efeitos adversos , Monócitos/metabolismo , Receptores de IgG/metabolismo , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Proteínas Ligadas por GPI/metabolismo , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Linfócitos T Reguladores/imunologia , Adulto Jovem
20.
Int J Med Sci ; 15(9): 892-899, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30008601

RESUMO

CD8+CD28-T cells (CD8Ts) exert immunosuppressive effects in various autoimmune diseases. The current study was designed to investigate the role of defects in CD8Ts in liver transplantation (LT). The proportion of CD8Ts in peripheral blood was determined by flow cytometry. The mean proportion of CD8Ts was 23.39% in recipients with stable graft function and 16.64% in those with graft dysfunction following LT compared with 19.86% in the healthy cohort. After receiving enhanced immunosuppressive therapy, patients in the rejection group who achieved recovery of graft function showed an increase in the proportion of CD8Ts (from 17.39% to 25.55%), but those in the group with refractory graft dysfunction showed no significant change (12.49% to 10.30%). Furthermore, in the first year after LT, recipients longer removed in time from the LT date exhibited a higher proportion of CD8Ts. Patients benefited most from tacrolimus concentrations of 5-10 ng/ml in the first year after LT and 0-5 ng/ml thereafter. Moreover, the change in the proportion of CD8Ts (ΔCD8Ts) was significantly higher in recipients with stable graft function than in those with graft dysfunction. These results suggest that a high frequency of CD8Ts prevents rejection and contributes to reduce immunosuppressant dosage and even induces tolerance.


Assuntos
Antígenos CD28 , Linfócitos T CD8-Positivos , Rejeição de Enxerto/imunologia , Imunossupressores/administração & dosagem , Transplante de Fígado , Adulto , Linfócitos T CD4-Positivos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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