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1.
Viruses ; 16(7)2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39066313

RESUMO

Hepatitis B surface antigen (HBsAg) is not only the biomarker of hepatitis B virus (HBV) infection and expression activity in hepatocytes, but it also contributes to viral specific T cell exhaustion and HBV persistent infection. Therefore, anti-HBV therapies targeting HBsAg to achieve HBsAg loss are key approaches for an HBV functional cure. In this study, we found that YZH-106, a rupestonic acid derivative, inhibited HBsAg secretion and viral replication. Further investigation demonstrated that YZH-106 promoted the lysosomal degradation of viral L- and M-HBs proteins. A mechanistic study using Biacore and docking analysis revealed that YZH-106 bound directly to the PreS2 domain of L- and M-HBsAg, thereby blocking their entry into the endoplasmic reticulum (ER) and promoting their degradation in cytoplasm. Our work thereby provides the basis for the design of a novel compound therapy to target HBsAg against HBV infection.


Assuntos
Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Lisossomos , Replicação Viral , Humanos , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Antígenos de Superfície da Hepatite B/metabolismo , Lisossomos/metabolismo , Replicação Viral/efeitos dos fármacos , Hepatite B/virologia , Hepatite B/tratamento farmacológico , Antivirais/farmacologia , Proteólise , Células Hep G2 , Hepatócitos/virologia , Hepatócitos/metabolismo , Simulação de Acoplamento Molecular , Ligação Proteica , Precursores de Proteínas
2.
World J Gastrointest Surg ; 16(2): 284-288, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38463359

RESUMO

This editorial discusses the article written by Zheng et al that was published in the latest edition of the World Journal of Gastrointestinal Surgery. Our primary focus is on the causes, location, diagnosis, histological classification, and therapy of ectopic pancreas. Ectopic pancreas refers to the presence of pancreatic tissue that is situated in a location outside its usual anatomical placement, and is not connected to the normal pancreas in terms of blood supply or anatomical structure. Currently, the embryological origin of ectopic pancreas remains uncertain. The most prevalent form of ectopic pancreatic is gastric ectopic pancreas. Endoscopic ultrasonography examination can visualize the morphological characteristics of the ectopic pancreatic lesion and pinpoint its anatomical location. The histological categorization of ectopic pancreas evolves. Endoscopic treatment has been widely advocated in ectopic pancreas.

3.
Cancer Immunol Immunother ; 72(12): 4337-4354, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37932427

RESUMO

The placenta and tumors can exhibit a shared expression profile of proto-oncogenes. The basis of placenta-derived heat shock protein gp96, which induces prophylactic and therapeutic T cell responses against cancer including hepatocellular carcinoma (HCC), remains unknown. Here, we identified the associated long peptides from human placental gp96 using matrix-assisted laser desorption/ionization-time-of-flight and mass spectrometry and analyzed the achieved proteins through disease enrichment analysis. We found that placental gp96 binds to numerous peptides derived from 73 proteins that could be enriched in multiple cancer types. Epitope-harboring peptides from glypican 3 (GPC3) and paternally expressed gene 10 (PEG10) were the major antigens mediating anti-HCC T cell immunity. Molecular docking analysis showed that the GPC3- and PEG10-derived peptides, mainly obtained from the cytotrophoblast layer of the mature placenta, bind to the lumenal channel and client-bound domain of the gp96 dimer. Immunization with bone marrow-derived dendritic cells pulsed with recombinant gp96-GPC3 or recombinant gp96-PEG10 peptide complex induced specific T cell responses, and T cell transfusion led to pronounced growth inhibition of HCC tumors in nude mice. We demonstrated that the chaperone gp96 can capture antigenic peptides as an efficient approach for defining tumor rejection oncoantigens in the placenta and provide a basis for developing GPC3 and PEG10 peptide-based vaccines against HCC. This study provides insight into the underlying mechanism of the antitumor response mediated by embryonic antigens from fetal tissues, and this will incite more studies to identify potential tumor rejection antigens from placenta.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Feminino , Humanos , Camundongos , Gravidez , Antígenos de Neoplasias , Proteínas Reguladoras de Apoptose/metabolismo , Carcinoma Hepatocelular/terapia , Proteínas de Ligação a DNA/metabolismo , Glipicanas , Neoplasias Hepáticas/terapia , Camundongos Nus , Simulação de Acoplamento Molecular , Peptídeos , Placenta/metabolismo , Proteínas de Ligação a RNA
4.
Front Physiol ; 14: 1182755, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37250119

RESUMO

Background: In recent years, identifying players with injury risk through physical fitness assessment has become a hot topic in sports science research. Although practitioners have conducted many studies on the relationship between physical fitness and the likelihood of injury, the relationship between the two remains indeterminate. Consequently, this study utilized machine learning to preliminary investigate the relationship between individual physical fitness tests and injury risk, aiming to identify whether patterns of physical fitness change have an impact on injury risk. Methods: This study conducted a retrospective analysis by extracting the records of 17 young female basketball players from the sport-specific physical fitness monitoring and injury registration database in Fujian Province. Sports-specific physical fitness tests included physical performance, physiological, biochemical, and subjective perceived responses. The data for each player was standardized individually using Z-scores. Synthetic minority over-sampling techniques and edited nearest neighbor algorithms were used to sample the training set to address the negative impact of class imbalance on model performance. Feature extraction was performed on the dataset using linear discriminant analysis, and the prediction model was constructed using the cost-sensitive neural network. Results: The 10 replicate 5-fold stratified cross-validation showed that the lower limb non-contact injury prediction model based on the cost-sensitive neural network had achieved good discrimination and calibration (average Precision: 0.6360; average Recall: 0.8700; average F2-Score: 0.7980; average AUC: 0.8590; average Brier-score: 0.1020), which could be well applied in training practice. According to the attribution analysis, agility and speed were important physical attributes that affect youth female basketball players' non-contact lower limb injury risk. Specifically, there was enhance in the performance of the 1-min double under, accompanied by an increase in urinary ketone and urinary blood levels following the agility test. The 3/4 basketball court sprint performance improved, while urinary protein and RPE levels decreased after the speed test. Conclusion: The sport-specific physical fitness change pattern can impact the lower limb non-contact injury risk of young female basketball players in Fujian Province, specifically in terms of agility and speed. These findings will provide valuable insights for planning athletes' physical training programs, managing fatigue, and preventing injuries.

5.
J Mol Cell Biol ; 15(5)2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-37204028

RESUMO

Alpha-fetoprotein (AFP) is the most widely used biomarker for the diagnosis of hepatocellular carcinoma (HCC). However, a substantial proportion of HCC patients have either normal or marginally increased AFP levels in serum, and the underlying mechanisms are not fully understood. In the present study, we provided in vitro and in vivo evidence that heat shock protein gp96 promoted AFP expression at the transcriptional level in HCC. NR5A2 was identified as a key transcription factor for the AFP gene, and its stability was enhanced by gp96. A further mechanistic study by co-immunoprecipitation, GST pull-down, and molecular docking showed gp96 and the SUMO E3 ligase RanBP2 competitively binding to NR5A2 at the sites spanning from aa 507 to aa 539. The binding of gp96 inhibited SUMOylation, ubiquitination, and subsequent degradation of NR5A2. In addition, clinical analysis of HCC patients indicated that gp96 expression in tumors was positively correlated with serum AFP levels. Therefore, our study uncovered a novel mechanism that gp96 regulates the stability of its client proteins by directly affecting their SUMOylation and ubiquitination. These findings will help in designing more accurate AFP-based HCC diagnosis and progression monitoring approaches.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , alfa-Fetoproteínas , Humanos , alfa-Fetoproteínas/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/patologia , Simulação de Acoplamento Molecular , Receptores Citoplasmáticos e Nucleares/metabolismo , Sumoilação , Ubiquitinação
6.
J Clin Med ; 11(19)2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36233502

RESUMO

This retrospective study investigated the toricity of dual-axis corneal refractive therapy (CRT) orthokeratology lenses and corneal parameters, including flat keratometry (FK), flat eccentricity (e), steep e, corneal astigmatism, and the difference in elevation at 8 mm chord length. We analyzed the right eyes of 143 adolescent patients who underwent ocular examinations, subjective refraction, and corneal topography before CRT lens fitting by trial lens evaluation. After orthokeratology treatment, all patients underwent a topography map with an intact plus power ring and decentration of <1 mm. The mean patient age was 10.7 ± 2.2 years old; 33% were male. The lens toricity range was 25−100 µm. Multiple linear regression analysis showed significant associations between CRT lens toricity and corneal astigmatism (ß = 10.913, t = 3.012, p = 0.003) and the difference in elevation at 8 mm chord length (ß = 0.681, t = 4.049, p < 0.001); no association was found between CRT lens toricity and FK, flat e, or steep e (all p > 0.05). Corneal astigmatism was positively associated with difference in elevation at 8 mm chord length (r = 0.743, p < 0.001, Pearson's correlation), and corneal astigmatism and the difference in elevation at 8 mm chord length were positively associated with CRT lens toricity (r = 0.657 and r = 0.643, respectively; both p < 0.01, Spearman's correlation). These results suggest that difference in elevation at 8 mm chord length can be used to conveniently estimate CRT lens toricity in clinical practice, using the equation Y (CRT lens toricity) = 1.02X (difference in elevation at 8 mm chord length) + 20.3.

7.
Sheng Wu Gong Cheng Xue Bao ; 38(9): 3363-3378, 2022 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-36151806

RESUMO

Breast cancer is the most common tumor in female, which seriously threatens the health of women. Triple-negative breast cancer is a subtype with the worst prognosis because of its special physiological characteristics and lack of targeted drugs. Therefore, it is urgent to develop new targeted treatments to improve the prognosis and survival rate of the patients. Previous studies have shown that heat shock protein gp96 is expressed on the membrane of a variety of cancer cells but not on the normal cells. Cell membrane gp96 levels are closely related to the poor prognosis of breast cancer, which may serve as a new target for breast cancer treatment. Based on the structure of gp96, we designed an α-helical peptide p37 that specifically targeting the ATP binding region of gp96. To improve the stability and decrease the degradation of the peptide, the N-terminus or C-terminus of p37 was coupled to PEG2000 or PEG5000 respectively, and four PEGylated polypeptides were obtained: mPEG2000CY, mPEG5000CY, mPEG2000LC, and mPEG5000LC. The PEGylated polypeptides inhibited the proliferation and invasion of breast cancer cell SK-BR-3, among which mPEG2000CY showed the most significant inhibitory effect. The half-life of mPEG2000CY in vivo was significantly longer than p37, and it effectively inhibited the growth of xenografted tumors of triple-negative breast cancer MDA-MB-231. The results provide a basis for the development of new targeted drugs against breast cancer, especially the triple-negative breast cancer.


Assuntos
Proteínas de Choque Térmico , Neoplasias de Mama Triplo Negativas , Trifosfato de Adenosina , Feminino , Humanos , Peptídeos/farmacologia , Polietilenoglicóis , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
8.
J Immunol ; 208(11): 2558-2572, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35562117

RESUMO

Kupffer cells (KCs), the largest tissue-resident macrophage population in the body, play a central role in maintaining a delicate balance between immune tolerance and immunity in the liver. However, the underlying molecular mechanism remains elusive. In this study, we show that KCs express high levels of miR-146a, which is under control of the PU.1 transcription factor. miR-146a deficiency promoted KCs differentiation toward a proinflammatory phenotype; conversely, miR-146a overexpression suppressed this phenotypic differentiation. We found that hepatitis B virus (HBV) persistence or HBV surface Ag treatment significantly upregulated miR-146a expression and thereby impaired polarization of KCs toward a proinflammatory phenotype. Furthermore, in an HBV carrier mouse model, KCs depletion by clodronate liposomes dramatically promoted HBV clearance and enhanced an HBV-specific hepatic CD8+ T cell and CD4+ T cell response. Consistent with this finding, miR-146a knockout mice cleared HBV faster and elicited a stronger adaptive antiviral immunity than wild-type mice. In vivo IL-12 blockade promoted HBV persistence and tempered the HBV-specific CTL response in the liver of miR-146a knockout mice. Taken together, our results identified miR-146a as a critical intrinsic regulator of an immunosuppressive phenotype in KCs under inflammatory stimuli, which may be beneficial in maintenance of liver homeostasis under physiological condition. Meanwhile, during HBV infection, miR-146a contributed to viral persistence by inhibiting KCs proinflammatory polarization, highlighting its potential as a therapeutic target in HBV infection.


Assuntos
Hepatite B , Tolerância Imunológica , Células de Kupffer , MicroRNAs , Animais , Hepatite B/imunologia , Vírus da Hepatite B , Células de Kupffer/imunologia , Camundongos , Camundongos Knockout , MicroRNAs/genética
9.
Transl Oncol ; 19: 101388, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35259676

RESUMO

Punicalagin, which is derived from pomegranate peel, is reported to exert growth-inhibitory effects against various cancers. However, the underlying mechanisms have not been elucidated. Human papillomavirus (HPV), a major oncovirus, utilizes the host autophagic machinery to support its replication. Here, punicalagin markedly downregulated the levels of the major HPV oncoproteins E6 and E7 in cervical cancer cells through the autophagy-lysosome system. Additionally, punicalagin activated the reactive oxygen species (ROS)-JNK pathway and promoted the phosphorylation of BCL2, which led to the dissociation of BCL2 from BECN1 and the induction of autophagy. Treatment with autophagy and JNK inhibitors or ROS scavengers mitigated the punicalagin-induced degradation of E6 and E7. Moreover, the knockout of ATG5 using the clustered regularly interspaced palindrome repeat/Cas 9 system mitigated the punicalagin-induced downregulation of E6/E7. This indicated that punicalagin-induced degradation of E6 and E7 was dependent on autophagy. The results of in vivo studies demonstrated that punicalagin efficiently inhibits cervical cancer growth. In conclusion, this study elucidated a mechanism of punicalagin-induced autophagic degradation of E6 and E7. It will enable the future applications of punicalagin as a therapeutic for HPV-induced cervical cancer.

10.
iScience ; 24(12): 103445, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34877502

RESUMO

Upregulation and stabilization of Foxp3 expression in Tregs are essential for regulating Treg function and immune homeostasis. In this study, gp96 immunization showed obvious therapeutic effects in a Lyn -/- mouse model of systemic lupus erythematosus. Moreover, gp96 alleviated the initiation and progression of MOG-induced experimental autoimmune encephalomyelitis. Immunization of gp96 increased Treg frequency, expansion, and suppressive function. Gene expression profiling identified the NF-κB family member p65 and c-Rel as the key transcription factors for enhanced Foxp3 expression in Treg by gp96. Mutant gp96 within its Toll-like receptor (TLR) binding domain, TLR2 knockout mice, and mice with cell-specific deletion of MyD88, were used to demonstrate that gp96 activated Tregs and induced Foxp3 expression via a TLR2-MyD88-mediated NF-κB signaling pathway. Taken together, these results show that gp96 immunization restricted antibody-induced and Th-induced autoimmune diseases by integrating Treg expansion and activation, indicating its potential clinical usefulness against autoimmune diseases.

11.
Sheng Wu Gong Cheng Xue Bao ; 37(11): 4036-4046, 2021 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-34841803

RESUMO

N-glycosylation modification, one of the most common protein post-translational modifications, occurs in heat shock protein gp96. The purpose of this study is to investigate the effect of N-glycosylation modification on immunologic function of the recombinant gp96 using the mutant gp96 in N-glycosylation sites. Firstly, wild-type and mutant gp96 proteins were expressed by insect expression system and their glycosylation levels were detected. To determine the effect of N-glycosylation on gp96 antigen presentation function, the IFN-γ+ CD8+ T cells in gp96-immunized mice and secretion level of IFN-γ were examined by flow cytometry and ELISA. The ATPase activity of gp96 was further detected by the ATPase kit. Finally, the effect of N-glycosylation on adjuvant function of gp96 for influenza vaccine was investigated in immunized mice. It was found that total sugar content of mutant recombinant gp96 was reduced by 27.8%. Compared to the wild type recombinant gp96, mutations in N-glycosylation sites resulted in decreased antigen presentation ability and ATPase activity of gp96. Furthermore, influenza vaccine-specific T cell levels induced by mutant gp96 as adjuvant were dramatically reduced compared to those by wild type recombinant gp96. These results demonstrate that N-glycosylation modification is involved in regulation of ATPase activity and antigen presentation function of gp96, thereby affecting its adjuvant function. The results provide the technical bases for development of gp96- adjuvanted vaccines.


Assuntos
Proteínas de Choque Térmico , Vacinas contra Influenza , Adjuvantes Imunológicos , Animais , Linfócitos T CD8-Positivos/metabolismo , Glicosilação , Camundongos
12.
Sheng Wu Gong Cheng Xue Bao ; 37(9): 3042-3060, 2021 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-34622616

RESUMO

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths and the fifth most common cancer worldwide. Clinically therapeutic options for HCC are very limited, and the overall survival rate of patients is very low. Therefore, early diagnosis and treatment of HCC have important impact on overall survival of patients. At present, alpha-fetoprotein (AFP) is one of the most widely used serological markers for HCC. Many evidences have shown that as a specific onco-protein, AFP has great research value in the occurrence, development, diagnosis and treatment of HCC. Here, we briefly introduce the molecular mechanism of AFP in the regulation of HCC occurrence and development, and its role in tumor escape from immune surveillance. We focus on the application of AFP as an important HCC target or carcino-embryonic antigen (CEA) in HCC clinical diagnosis and treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/terapia , Detecção Precoce de Câncer , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/terapia , alfa-Fetoproteínas
14.
Sheng Wu Gong Cheng Xue Bao ; 36(9): 1701-1712, 2020 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-33164449

RESUMO

Toll like receptors (TLRs) are pattern recognition receptors and represent immune receptors in innate immunity. They are very conservative in evolution and extremely important for the survival of organisms. TLRs initiate signal transduction through binding of endogenous or exogenous ligands to activate a series of downstream important gene expression and activation. Studies have shown that regulatory T cells (Tregs) play a central role in maintaining peripheral immune tolerance and preventing transplant rejection. Tregs express certain TLRs, including TLR2, TLR4, TLR5, TLR7, TLR8, and TLR9. Activation of TLRs may directly or indirectly affect (mainly activate) Treg proliferation and immunosuppressive functions, and this regulation is closely related to the occurrence of infection, autoimmune disease and cancer. The heat shock proteins as TLRs ligand molecules play important roles in the regulation of Treg. Therefore, understanding regulatory mechanisms of TLR pathways on Tregs is of great significance for new drug development and targeted therapy. This review introduces how TLR-mediated pathways regulate Tregs' immune function.


Assuntos
Citocinas , Linfócitos T Reguladores , Imunidade Inata , Transdução de Sinais , Receptores Toll-Like/genética
15.
Sci Rep ; 10(1): 12596, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32724151

RESUMO

Liver failure leads to the massive necrosis of hepatocytes, releasing large amounts of intracellular components including damage-associated molecular patterns (DAMPs). We found that extracellular gp96 levels in serum were elevated in patients with chronic hepatitis B infection (CHB) and acute-on-chronic liver failure (ACLF). Meanwhile, the gp96 level positively correlated with hepatic necroinflammation. We employed two mouse liver damage and liver failure models induced by lipopolysaccharide (LPS) plus D-galactosamine (D-Galn), and concanavalin A (ConA) to identify the function of extracellular gp96. As a result, the inhibition of extracellular gp96 by a specific peptide efficiently mitigated both LPS/D-Galn- and ConA-induced liver injury and immune hyperactivation, whereas exogenous gp96 aggravated the symptoms of hepatic injury in mice but not in Kupffer cells-ablated mice. The exposure of Kupffer cells to gp96 induced the secretion of pro-inflammatory cytokines. Collectively, our data demonstrate that gp96 released from necrotic hepatocytes aggravates immune hyperactivation and promotes liver damage and possibly the development of liver failure mainly by activating Kupffer cells.


Assuntos
Doença Hepática Terminal/metabolismo , Falência Hepática Aguda/metabolismo , Glicoproteínas de Membrana/metabolismo , Adulto , Animais , Modelos Animais de Doenças , Doença Hepática Terminal/imunologia , Feminino , Humanos , Falência Hepática Aguda/imunologia , Masculino , Glicoproteínas de Membrana/sangue , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade
16.
PLoS One ; 15(7): e0228302, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32628668

RESUMO

Programmed death ligand 1 (PD-L1) has been recently shown to be a major obstacle to antiviral immunity by binding to its receptor programmed death 1 (PD-1) on specific IFN-γ producing T cells in chronic hepatitis B. Currently, IFN-α is widely used to treat hepatitis B virus (HBV) infection, but its antiviral effect vary greatly and the mechanism is not totally clear. We found that IFN-α/γ induced a marked increase of PD-L1 expression in hepatocytes. Signal and activators of transcription (Stat1) was then identified as a major transcription factor involved in IFN-α/γ-mediated PD-L1 elevation both in vitro and in mice. Blockage of the PD-L1/PD-1 interaction by a specific mAb greatly enhanced HBV-specific T cell activity by the gp96 adjuvanted therapeutic vaccine, and promoted HBV clearance in HBV transgenic mice. Our results demonstrate the IFN-α/γ-Stat1-PD-L1 axis plays an important role in mediating T cell hyporesponsiveness and inactivating liver-infiltrating T cells in the hepatic microenvironment. These data raise further potential interest in enhancing the anti-HBV efficacy of IFN-α and therapeutic vaccines.


Assuntos
Antígeno B7-H1/metabolismo , Vírus da Hepatite B/imunologia , Interferon-alfa/farmacologia , Interferon gama/farmacologia , Fator de Transcrição STAT1/metabolismo , Linfócitos T/imunologia , Regulação para Cima/efeitos dos fármacos , Animais , Anticorpos Monoclonais/uso terapêutico , Antígeno B7-H1/química , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Sítios de Ligação , Linhagem Celular , Hepatite B/tratamento farmacológico , Hepatite B/veterinária , Antígenos de Superfície da Hepatite B/sangue , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Receptor de Morte Celular Programada 1/metabolismo , Regiões Promotoras Genéticas , Fator de Transcrição STAT1/química , Linfócitos T/metabolismo
17.
J Gen Virol ; 100(8): 1241-1252, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31204972

RESUMO

In hepatitis B virus (HBV) infection, the virus produces redundant hepatitis B surface antigen (HBsAg) that plays a key role in driving T-cell tolerance and viral persistence. However, currently available anti-HBV agents have no direct effect on HBsAg transcription and protein expression. In this study, we designed a heat shock protein gp96 inhibitor p37 with the cell penetrating peptide PTD (protein transduction domain of trans-activator of transcription), which mediated p37 internalization into hepatocytes. PTD-p37 effectively suppressed HBsAg expression and viral replication both in vitro and in vivo. We further provide evidence that PTD-p37 suppressed HBV enhancer/promoter activity via p53 upregulation. Moreover, PTD-p37 had antiviral activity against a lamivudine-resistant HBV strain. Considering that suppression of HBsAg expression is a major goal for treatment of HBV infection, our results provide a basis for developing a new therapeutic approaches targeting host factors against viral expression.


Assuntos
Antivirais/farmacologia , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/fisiologia , Hepatite B/genética , Glicoproteínas de Membrana/antagonistas & inibidores , Peptídeos/farmacologia , Proteína Supressora de Tumor p53/genética , Animais , Feminino , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Hepatite B/metabolismo , Hepatite B/virologia , Antígenos de Superfície da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Hepatócitos/virologia , Humanos , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Regiões Promotoras Genéticas/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
18.
Mol Cancer ; 17(1): 113, 2018 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-30068375

RESUMO

BACKGROUND: HER2 gene amplification generates an enormous number of HER2 transcripts, but the global effects on endogenous miRNA targets including HER family members in breast cancer are unexplored. METHODS: We generated a HER2-3'UTR expressing vector to test the tumor-promoting properties in HER2 low expressing T47D and MCF7 cells. Through microarray analysis and real-time PCR analysis we identified genes that were regulated by HER2-3'UTR. Positive and negative manipulation of miRNA expression, response element mutational studies and transcript reporter assays were performed to explore the mechanism of competitive sequestration of miR125a/miRNA125b by HER2 3'UTR. To investigate if trastuzumab-induced upregulation of HER3 is also mediated through miRNA de-repression, we used the CRISPR/cas9 to mutate the endogenous HER2 mRNA in HER2 over-expressing Au565 cells. Finally, we looked at cohorts of breast cancer samples of our own and the TCGA to show if HER2 and HER3 mRNAs correlate with each other. RESULTS: The HER2 3'UTR pronouncedly promoted cell proliferation, colony formation, and breast tumor growth. High-throughput sequencing revealed a significant increase in HER3 mRNA and protein levels by the HER2 3'untranslated region (3'UTR). The HER2 3'UTR harboring a shared miR-125a/b response element induced miR-125a/b sequestration and thus resulted in HER3 mRNA derepression. Trastuzumab treatment upregulated HER3 via elevated HER2 mRNA expression, leading to trastuzumab resistance. Depletion of miR-125a/b enhanced the antitumor activity of trastuzumab. Microarray data from HER2-overexpressing primary breast cancer showed significant elevation of mRNAs for predicted miR-125a/b targets compared to non-targets. CONCLUSIONS: These results suggest that HER2 3'UTR-mediated HER3 upregulation is involved in breast cell transformation, increased tumor growth, and resistance to anti-HER2 therapy. The combinatorial targeting of HER3 mRNA or miR-125a/b may offer an effective tool for breast cancer therapy.


Assuntos
Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos , MicroRNAs/genética , Receptor ErbB-2/genética , Receptor ErbB-3/genética , Regulação para Cima , Regiões 3' não Traduzidas , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Receptor ErbB-3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Trastuzumab , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Mol Ther Nucleic Acids ; 10: 361-375, 2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29499948

RESUMO

The reciprocal interaction between influenza virus and host microRNAs (miRNAs) has been implicated in the regulation of viral replication and host tropism. However, the global roles of the cellular miRNA repertoire and the mechanisms of miRNA-mediated antiviral defense await further elucidation. In this study, we systematically screened 297 cellular miRNAs from human and mouse epithelial cells and identified five inhibitory miRNAs that efficiently inhibited influenza virus replication in vitro and in vivo. Among these miRNAs, hsa-mir-127-3p, hsa-mir-486-5p, hsa-mir-593-5p, and mmu-mir-487b-5p were found to target at least one viral gene segment of both the human seasonal influenza H3N2 and the attenuated PR8 (H1N1) virus, whereas hsa-miR-1-3p inhibited viral replication by targeting the supportive host factor ATP6V1A. Moreover, the number of miRNA binding sites in viral RNA segments was positively associated with the activity of host miRNA-induced antiviral defense. Treatment with a combination of the five miRNAs through agomir delivery pronouncedly suppressed viral replication and effectively improved protection against lethal challenge with PR8 in mice. These data suggest that the highly expressed miRNAs in respiratory epithelial cells elicit effective antiviral defenses against influenza A viruses and will be useful for designing miRNA-based therapies against viral infection.

20.
Oncotarget ; 8(51): 88645-88657, 2017 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-29179464

RESUMO

Dissection and understanding of the molecular pathways driving triple-negative breast cancer (TNBC) are urgently needed to develop efficient tailored therapies. Aside from cell invasion and metastasis, the urokinase-type plasminogen activator receptor (uPAR) has been linked to apoptosis resistance in breast tumors. We explored the mechanism of uPAR-disrupted apoptosis in breast cancer. We found that depletion of uPAR by RNAi increases death receptor 4 (DR4) and death receptor 5 (DR5) expression and triggers TRAIL-induced apoptosis in TNBC cells. The microRNAs miR-17-5p and miR-20a inhibit cell apoptosis via suppression of DR4/DR5. We provide evidence that uPAR enhances miR-17-5p/20a expression through upregulation of c-myc. Blocking miR-17-5p/20a with antagomiRNA suppressed the growth of uPAR-overexpressing breast tumor xenografts in mice. These results indicate that uPAR suppresses cell apoptosis by inhibiting the c-myc-miR-17/5p/20a-DR4/DR5 pathway. Therapy directed at uPAR-induced miR-17/20a is a potential option for breast cancer and TNBC.

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