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1.
J Cell Mol Med ; 28(1): e18064, 2024 01.
Article in English | MEDLINE | ID: mdl-38031653

ABSTRACT

With the increasing incidence of oral cancer in the world, it has become a hotspot to explore the pathogenesis and prevention of oral cancer. It has been proved there is a strong link between periodontal pathogens and oral cancer. However, the specific molecular and cellular pathogenic mechanisms remain to be further elucidated. Emerging evidence suggests that periodontal pathogens-induced epithelial-mesenchymal transition (EMT) is closely related to the progression of oral cancer. Cells undergoing EMT showed increased motility, aggressiveness and stemness, which provide a pro-tumour environment and promote malignant metastasis of oral cancer. Plenty of studies proposed periodontal pathogens promote carcinogenesis via EMT. In the current review, we discussed the association between the development of oral cancer and periodontal pathogens, and summarized various mechanisms of EMT caused by periodontal pathogens, which are supposed to play an important role in oral cancer, to provide targets for future research in the fight against oral cancer.


Subject(s)
Mouth Neoplasms , Porphyromonas gingivalis , Humans , Mouth Neoplasms/pathology , Epithelial-Mesenchymal Transition , Carcinogenesis , Fusobacterium nucleatum
2.
Opt Express ; 32(1): 1003-1009, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38175106

ABSTRACT

We demonstrate a thermoreflectance-based thermometry technique with an ultimate temperature resolution of 60 µK in a 2.6 mHz bandwidth. This temperature resolution was achieved using a 532 nm-wavelength probe laser and a ∼1 µm-thick silicon transducer film with a thermoreflectance coefficient of -4.7 × 10-3 K-1 at room temperature. The thermoreflectance sensitivity reported here is over an order-of-magnitude greater than that of metal transducers, and is comparable to the sensitivity of traditional resistance thermometers. Supporting calculations reveal that the enhancement in sensitivity is due to optical interference in the thin film.

3.
Lipids Health Dis ; 23(1): 321, 2024 Sep 28.
Article in English | MEDLINE | ID: mdl-39342327

ABSTRACT

BACKGROUND: Periodontitis, a persistent inflammatory condition, significantly impairs individuals' overall quality of life. Lymphocyte-to-high-density lipoprotein cholesterol ratio (LHR), monocyte-to-high-density lipoprotein cholesterol ratio (MHR), neutrophil-to-high-density lipoprotein cholesterol ratio (NHR), and platelet-to-high-density lipoprotein cholesterol ratio (PHR) are new convenient and economical biomarkers. However, whether the above high-density lipoprotein-related inflammatory biomarkers are associated with periodontitis has rarely been investigated. Therefore, the research endeavor focused on uncovering potential relationships. METHODS: The research encompassed a diverse and extensive sample, comprising 9,470 participants, selected from the National Health and Nutrition Examination Survey spanning the years 2009 to 2014. The association between high-density lipoprotein-related inflammatory biomarkers and periodontitis was explored utilizing a multivariable logistic regression model with weighted analysis. Additionally, the study employed smoothed curve fitting to explore potential nonlinear relationships. Further stratified analyses and interaction tests were performed. RESULTS: This study indicated no apparent association between MHR and PHR with periodontitis, whereas LHR and NHR demonstrated a statistically significant positive relationship with the prevalence of periodontitis. In the fully adjusted model, participants belonging to the highest tertile of both LHR and NHR showed a notably higher likelihood of having periodontitis compared to those in the lowest tertile (LHR: OR = 1.22, 95% CI: 1.06, 1.39; NHR: OR = 1.27, 95% CI: 1.09, 1.49). Furthermore, smooth curve fitting was employed to investigate the potential nonlinear relationship between LHR, NHR, and periodontitis. The results indicated that there was a significant increase in the occurrence of periodontitis when Log2 (LHR) exceeded 1.01 and Log2(NHR) surpassed 2.16 (Log2(LHR): OR = 1.42; 95% CI: 1.19, 1.69; Log2(NHR): OR = 1.40; 95% CI: 1.15, 1.71). The subgroup analysis revealed that the associations between periodontitis and either LHR or NHR, separately, were more pronounced among individuals under the age of 50 and those without hypertension. CONCLUSIONS: This cross-sectional study revealed a positive relationship between LHR、NHR and periodontitis, particularly when these indicators exceeded their thresholds. LHR and NHR may serve as potential inflammatory markers for identifying periodontitis, thereby facilitating early warning for both patients and dentists, and enabling early intervention in the oral environment. Besides, extensive prospective cohort investigations are essential to confirm and solidify this observation.


Subject(s)
Biomarkers , Inflammation , Nutrition Surveys , Periodontitis , Humans , Periodontitis/blood , Periodontitis/epidemiology , Male , Female , Middle Aged , Adult , Inflammation/blood , Biomarkers/blood , Cholesterol, HDL/blood , Monocytes/metabolism , Neutrophils , Aged , Lymphocytes/metabolism , Lipoproteins, HDL/blood , Cross-Sectional Studies , Blood Platelets/pathology , Logistic Models
4.
Int J Mol Sci ; 25(2)2024 Jan 06.
Article in English | MEDLINE | ID: mdl-38255811

ABSTRACT

Porphyromonas gingivalis (P. gingivalis) is a key pathogen of periodontitis. Increasing evidence shows that P. gingivalis signals to mitochondria in periodontal cells, including gingival epithelial cells, gingival fibroblast cells, immune cells, etc. Mitochondrial dysfunction affects the cellular state and participates in periodontal inflammatory response through the aberrant release of mitochondrial contents. In the current review, it was summarized that P. gingivalis induced mitochondrial dysfunction by altering the mitochondrial metabolic state, unbalancing mitochondrial quality control, prompting mitochondrial reactive oxygen species (ROS) production, and regulating mitochondria-mediated apoptosis. This review outlines the impacts of P. gingivalis and its virulence factors on the mitochondrial function of periodontal cells and their role in periodontitis.


Subject(s)
Mitochondrial Diseases , Periodontitis , Humans , Porphyromonas gingivalis , Mitochondria , Apoptosis
5.
Anal Bioanal Chem ; 408(12): 3185-201, 2016 May.
Article in English | MEDLINE | ID: mdl-27025382

ABSTRACT

Diarylheptanoid A, 5-hydroxy-7-(4'-hydroxy-3'-methoxyphenyl)-1-phenyl-3-heptanone, is a naturally occurring phytochemical ingredient isolated from the rhizome of Alpinia officinarum. In order to confirm the anti-inflammatory activity of diphenylheptane A, we investigated its effects on lipopolysaccharide (LPS)-induced pro-inflammatory mediators, such as nitric oxide (NO), prostaglandin E2 (PGE2), interleukin-1ß (IL-1ß), and tumor necrosis factor α (TNF-α), as well as upstream genes, including the inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear factor κB (NF-κB) p65, p38 mitogen-activated protein kinase (MAPK), and extracellular signal-regulated kinase 1/2 (ERK1/2). Our results have proved the anti-inflammatory property of diphenylheptane A. Based on this finding, an LPS-induced RAW264.7 cell inflammatory model was introduced to evaluate the anti-inflammatory activity associated with glycerophospholipid (GPL) metabolism regulated by diphenylheptane A. We applied ultra-performance liquid chromatography/electrospray ionization-quadruple time of flight-mass spectrometry (UPLC/ESI-QTOF-MS) to the metabolic profiling of GPL synthesis in LPS-stimulated macrophages with the aim of identifying differentially synthesized GPL metabolites. Sixteen GPL metabolites, whose changes were restored to normal level after diphenylheptane A treatment, were further screened to be considered as useful biomarkers of inflammation. Overall, our study revealed for the first time that diphenylheptane A reestablished the production of 16 plasma membrane GPLs to basal level in LPS-activated RAW264.7 cells, suggesting the potential therapeutic property of phytochemical compounds against inflammatory diseases.


Subject(s)
Chromatography, Liquid/methods , Dinoprostone/metabolism , Heptanes/pharmacology , Macrophages/metabolism , Nitric Oxide/metabolism , Spectrometry, Mass, Electrospray Ionization/methods , Animals , Cell Line , Mice
6.
J Hepatol ; 61(4): 832-9, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24845612

ABSTRACT

BACKGROUND & AIMS: The alterations of histone modification may serve as a promising diagnostic biomarker of hepatocellular carcinoma (HCC), but the clinical and mechanistic relatedness of the histone H3 lysine 27 and 4 trimethylation (H3K27me3 and H3K4me3) in HCC remains poorly understood. Here we propose that the combination of H3K27me3 and H3K4me3 is a more precise predictive/prognostic value for outcome of HCC patients. METHODS: We used chromatin immunoprecipitation (ChIP) assays and a ChIP-on-chip screen to analyse HCC. RESULTS: We found that the EZH2 occupancy coincides with the H3K27me3 at promoters and directly silences the transcription of target genes in HCC. The H3K27me3-related gene network of EZH2 contains well-established genes, such as CDKN2A, as well as previously unappreciated genes, including FOXO3, E2F1, and NOTCH2, among others. We further observed independently increasing profiles of H3K27me3 and H3K4me3 at the promoters of certain target genes in HCC specimens. Importantly, Kaplan-Meier analysis reveals that 3-year overall and tumour-free survival rates are dramatically reduced in patients that simultaneously express EZH2 and menin, compared to rates in the EZH2 or menin under expressing patients. Furthermore, an inhibitor of H3K27me3 alone, or in combination with an H3K4me3 inhibitor, effectively blocked the aggressive phenotype of HCC cells. CONCLUSIONS: Our results indicate that a combined analysis of both H3K27me3 and H3K4me3 may serve as powerful diagnostic biomarkers of HCC, and targeting both might benefit anti-HCC therapy.


Subject(s)
Carcinoma, Hepatocellular , Histones , Polycomb Repressive Complex 2/genetics , Proto-Oncogene Proteins/genetics , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Enhancer of Zeste Homolog 2 Protein , Female , Gene Expression Regulation, Neoplastic , Genes, Tumor Suppressor , Histones/analysis , Histones/metabolism , Humans , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Male , Methylation , Middle Aged , Neoplasm Staging , Prognosis , Protein Processing, Post-Translational/genetics
7.
Nucleic Acids Res ; 39(22): e153, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21976726

ABSTRACT

The identification of human cancer-related microRNAs (miRNAs) is important for cancer biology research. Although several identification methods have achieved remarkable success, they have overlooked the functional information associated with miRNAs. We present a computational framework that can be used to prioritize human cancer miRNAs by measuring the association between cancer and miRNAs based on the functional consistency score (FCS) of the miRNA target genes and the cancer-related genes. This approach proved successful in identifying the validated cancer miRNAs for 11 common human cancers with area under ROC curve (AUC) ranging from 71.15% to 96.36%. The FCS method had a significant advantage over miRNA differential expression analysis when identifying cancer-related miRNAs with a fine regulatory mechanism, such as miR-27a in colorectal cancer. Furthermore, a case study examining thyroid cancer showed that the FCS method can uncover novel cancer-related miRNAs such as miR-27a/b, which were showed significantly upregulated in thyroid cancer samples by qRT-PCR analysis. Our method can be used on a web-based server, CMP (cancer miRNA prioritization) and is freely accessible at http://bioinfo.hrbmu.edu.cn/CMP. This time- and cost-effective computational framework can be a valuable complement to experimental studies and can assist with future studies of miRNA involvement in the pathogenesis of cancers.


Subject(s)
MicroRNAs/metabolism , Neoplasms/genetics , Computational Biology , Gene Expression Regulation, Neoplastic , Genes, Neoplasm , Humans , Neoplasms/metabolism , Thyroid Neoplasms/genetics
8.
J Food Sci ; 86(3): 779-791, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33598925

ABSTRACT

Pu-erh tea is believed to be a beneficial beverage for health due to its many kinds of pharmacological effects. Nevertheless, detailed information related to differences in metabolites of Pu-erh raw tea from different geographical origins remains scarce. In this study, 43 elements were found in water-soluble components of Pu-erh raw tea by highly sensitive ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (U-HPLC/Q-TOF-MS). The characteristic groups of 29 metabolites from nondestructive proton nuclear magnetic resonance (1 H-NMR) spectroscopy were assigned. The variables contributed largely to the origin classification, mainly including valine, threonine, chlorogenic acid, quinic acid, epiafzelechin, and gallic acid ester, were screened out by sparse partial least squares discriminant analysis (sPLS-DA) method. This study provided a feasible and rapid technique for distinguishing Pu-erh tea from different areas by 1 H-NMR combined with sPLS-DA.


Subject(s)
Camellia sinensis/classification , Tea/classification , Camellia sinensis/chemistry , Catechin , Chromatography, High Pressure Liquid , Discriminant Analysis , Flavonoids/analysis , Least-Squares Analysis , Magnetic Resonance Spectroscopy , Mass Spectrometry , Plant Extracts/chemistry , Tea/chemistry
9.
Cancer Gene Ther ; 27(7-8): 539-547, 2020 08.
Article in English | MEDLINE | ID: mdl-31383953

ABSTRACT

Several brain tumors is closely related to the disorder of chromatin histone modification, whereas the epigenetic mechanisms of the incidence of highly malignant adult glioma is not yet deeply studied. Deletion or mutation of the MEN1 gene, which encodes the epigenetic regulator menin, specifically induces poorly differentiated neuroendocrine tumors; however, the biological and clinical importance of MEN1 in the nervous system remains poorly understood. Menin expression was robustly activated in 44.4% of adult gliomas. Abnormally high expression of menin was closely related to a shorter median survival time of 20 months, a larger tumor volume and a higher percentage of Ki67 staining. Interestingly, menin expression was also activated in the cytoplasm of tumor cells (38.8%) and was also closely related to the poor prognosis of patients with glioma. Importantly, in a screening of 96 types of small-molecule targeted histone modification regulators, menin inhibitors were found to significantly block the proliferation of adult glioma cells. Our findings confirm that menin is a potential biomarker of poor prognosis in adult gliomas, independent of the WHO grade. Targeting menin may effectively inhibit certain gliomas, and this information provides novel insight into therapeutic strategies for glioma.


Subject(s)
Brain Neoplasms/genetics , Gene Expression Regulation, Neoplastic , Glioma/genetics , Proto-Oncogene Proteins/genetics , Adult , Aged , Brain Neoplasms/metabolism , Female , Glioma/diagnosis , Glioma/metabolism , Humans , Male , Middle Aged , Mutation , Prognosis , Young Adult
10.
Nat Commun ; 11(1): 1009, 2020 02 21.
Article in English | MEDLINE | ID: mdl-32081882

ABSTRACT

The MEN1 gene, a tumor suppressor gene that encodes the protein menin, is mutated at high frequencies in neuroendocrine (NE) tumors; however, the biological importance of this gene in NE-type lung cancer in vivo remains unclear. Here, we established an ATII-specific KrasG12D/+/Men1-/- driven genetically engineered mouse model and show that deficiency of menin results in the accumulation of DNA damage and antagonizes oncogenic Kras-induced senescence and the epithelial-to-mesenchymal transition during lung tumorigenesis. The loss of menin expression in certain human primary lung cancers correlates with elevated NE profiles and reduced overall survival.


Subject(s)
DNA Damage/genetics , Lung Neoplasms/genetics , Neuroendocrine Tumors/genetics , Proto-Oncogene Proteins/deficiency , Proto-Oncogene Proteins/genetics , Animals , Carcinogenesis/genetics , Carcinogenesis/metabolism , Carcinogenesis/pathology , Cell Differentiation , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/metabolism , Cell Transformation, Neoplastic/pathology , Epithelial-Mesenchymal Transition/genetics , Female , Humans , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Male , Mice , Mice, Knockout , Neuroendocrine Tumors/metabolism , Neuroendocrine Tumors/pathology , Prognosis , Proto-Oncogene Proteins p21(ras)/genetics , Signal Transduction
11.
Biochim Biophys Acta Gene Regul Mech ; 1861(2): 117-124, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29413895

ABSTRACT

The expression of insulin-like growth factor 2 (IGF2), a classical imprinting gene, didn't completely correlate with its imprinting profiles in hepatocellular carcinoma (HCC). The mechanistic importance of promoter activity in regulation of IGF2 has not been fully clarified. Here we show that histone 3 lysine 4 trimethylation (H3K4me3) modified by menin-MLL complex of IGF2 promoter contributes to promoter activity of IGF2. The strong binding of menin and abundant H3K4me3 at the DNA demethylated P3/4 promoters were observed in Hep3B cells with the robust expression of IGF2. In IGF2-low-expressing HepG2 cells, menin didn't bind to DNA hypermethylated P3/4 regions; however, menin overexpression inhibited DNA methylation and promoted H3K4me3 at the P3/4 as well as IGF2 expression in HepG2. In addition, the H3K4me3 at P3/4 locus was activated in primary HCC specimens with high IGF2 expression. Furthermore, inhibition of the menin/MLL interaction via MI-2/3 reduced IGF2 expression, inhibited the IGF1R-AKT pathway, and significantly repressed HCC with robust expression of IGF2. Taken together, we conclude that H3K4me3 of P3/4 locus mediated by the menin-MLL complex is a novel epigenetic mechanism for releasing IGF2.


Subject(s)
Epigenesis, Genetic , Gene Expression Regulation, Neoplastic , Genomic Imprinting/genetics , Insulin-Like Growth Factor II/genetics , Promoter Regions, Genetic/genetics , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , DNA Methylation , Hep G2 Cells , Histone-Lysine N-Methyltransferase/genetics , Histone-Lysine N-Methyltransferase/metabolism , Histones/metabolism , Humans , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Lysine/metabolism , Methylation , Myeloid-Lymphoid Leukemia Protein/genetics , Myeloid-Lymphoid Leukemia Protein/metabolism , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism
12.
FEBS J ; 284(9): 1309-1323, 2017 05.
Article in English | MEDLINE | ID: mdl-28304152

ABSTRACT

Subset heterogeneity of the mononuclear phagocyte system (MPS) is controlled by defined transcriptional networks and programs; however, the dynamic establishment of programs that control broad, orchestrated expression of transcription factors (TFs) during the progression of monocyte-into-phagocyte (MP) differentiation remains largely unexplored. By using chromatin immunoprecipitation assays, we show the extensive trimethylation of histone H3 lysine 4 (H3K4me3) as well as histone H3 lysine 27 (H3K27me3) occupancy with broad footprints at the promoters of MP differentiation-related TFs, such as HOXA and FOXO genes, KLF4, IRF8 and others. The rapid repression of HOXA genes was closely associated with the MP differentiation program. H3K4me3 participates in regulating HOXA genes at mild and terminal differentiation periods, while H3K27me3 maintains low-level expression of HOXA genes at phagocytic maintenance periods. Furthermore, the reprogramming of H3K27me3 plays a major role in the up-regulation of KLF4 and FOXO genes during MP differentiation. Importantly, the pharmacological inhibition of H3K4me3 and/or H3K27me3 strikingly promotes the differentiation programs of THP-1 and K562 cells. Together, these findings elucidate mechanisms crucial to the dynamic establishment of epigenetic memory, which is central to the maintenance of the MP differentiation blockade.


Subject(s)
Epigenesis, Genetic , Gene Expression Regulation, Developmental , Histones/metabolism , Macrophages/metabolism , Monocytes/metabolism , Protein Processing, Post-Translational , Transcription Factors/metabolism , Animals , Bone Marrow Cells/cytology , Bone Marrow Cells/enzymology , Bone Marrow Cells/metabolism , Cell Differentiation , Cell Line, Tumor , Cells, Cultured , Chromatin Immunoprecipitation , Forkhead Transcription Factors , Homeodomain Proteins/antagonists & inhibitors , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Humans , Kruppel-Like Factor 4 , Lysine , Macrophages/cytology , Methylation , Mice, Inbred C57BL , Monocytes/cytology , Promoter Regions, Genetic , RNA Interference , Specific Pathogen-Free Organisms , Transcription Factors/antagonists & inhibitors , Transcription Factors/genetics
13.
Oncotarget ; 7(4): 4680-94, 2016 Jan 26.
Article in English | MEDLINE | ID: mdl-26717039

ABSTRACT

Glioblastoma (GBM) is one of the most lethal brain tumors with a short survival time. EGFR amplification and mutation is the most significant genetic signature in GBM. About half of the GBMs with EGFR amplification express a constitutively autophosphorylated variant of EGFR, known as EGFRvIII. Our in vitro data demonstrated further enhanced EGFRvIII activity and tumor cell invasion in the tumor microenvironment of hypoxia plus extracellular matrix (ECM) vitronectin, in which EGFRvIII and integrin ß3 tended to form complexes. The treatment with ITGB3 siRNA or the integrin antagonist cilengetide preferentially interrupted the EGFRvIII/integrin ß3 complex, effectively reduced tumor cell invasion and activation of downstream signaling effectors. Cilengitide is recently failed in Phase III CENTRIC trial in unselected patients with GBM. However, we found that cilengitide demonstrated efficacious tumor regression via inhibition of tumor growth and angiogenesis in EGFRvIII orthotopic xenografts. Bioinformatics analysis emphasized key roles of integrin ß3, hypoxia and vitronectin and their strong correlations with EGFRvIII expression in malignant glioma patient samples in vivo. In conclusion, we demonstrate that EGFRvIII/integrin ß3 complexes promote GBM progression and metastasis in the environment of hypoxia and vitronectin-enrichment, and cilengitide may serve as a promising therapeutics for EGFRvIII-positive GBMs.


Subject(s)
Brain Neoplasms/secondary , ErbB Receptors/metabolism , Glioblastoma/pathology , Hypoxia/pathology , Integrin beta3/metabolism , Tumor Microenvironment , Vitronectin/metabolism , Animals , Apoptosis , Blotting, Western , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Cell Movement , Cell Proliferation , Disease Progression , ErbB Receptors/genetics , Female , Fluorescent Antibody Technique , Gene Expression Regulation, Neoplastic , Glioblastoma/genetics , Glioblastoma/metabolism , Humans , Hypoxia/genetics , Hypoxia/metabolism , Immunoenzyme Techniques , Immunoprecipitation , Integrin beta3/genetics , Mice , Mice, Nude , Microscopy, Fluorescence , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Retrospective Studies , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction , Tumor Cells, Cultured , Vitronectin/genetics , Xenograft Model Antitumor Assays
14.
Neuro Oncol ; 16(9): 1229-43, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24861878

ABSTRACT

BACKGROUND: As a commonly mutated form of the epidermal growth factor receptor, EGFRvIII strongly promotes glioblastoma (GBM) tumor invasion and progression, but the mechanisms underlying this promotion are not fully understood. METHODS: Through gene manipulation, we established EGFRvIII-, wild-type EGFR-, and vector-expressing GBM cells. We used cDNA microarrays, bioinformatics analysis, target-blocking migration and invasion assays, Western blotting, and an orthotopic U87MG GBM model to examine the phenotypic shifts and treatment effects of EGFRvIII expression in vitro and in vivo. Confocal imaging, co-immunoprecipitation, and siRNA assays detected the focal adhesion-associated complex and their relationships to the EGFRvIII/JAK2/STAT3 axis in GBM cells. RESULTS: The activation of JAK2/STAT3 signaling is vital for promoting migration and invasion in EGFRvIII-GBM cells. AG490 or WP1066, the JAK2/STAT3 inhibitors, specifically destroyed EGFRvIII/JAK2/STAT3-related focal adhesions and depleted the activation of EGFR/Akt/FAK and JAK2/STAT3 signaling, thereby abolishing the ability of EGFRvIII-expressing GBM cells to migrate and invade. Furthermore, the RNAi silencing of JAK2 in EGFRvIII-expressing GBM cells significantly attenuated their ability to migrate and invade; however, as a result of a potential EGFRvIII-JAK2-STAT3 activation loop, neither EGFR nor STAT3 knockdown yielded the same effects. Moreover, AG490 or JAK2 gene knockdown greatly suppressed tumor invasion and progression in the U87MG-EGFRvIII orthotopic models. CONCLUSION: Taken together, our data demonstrate that JAK2/STAT3 signaling is essential for EGFRvIII-driven migration and invasion by promoting focal adhesion and stabilizing the EGFRvIII/JAK2/STAT3 axis. Targeting JAK2/STAT3 therapy, such as AG490, may have potential clinical implications for the tailored treatment of GBM patients bearing EGFRvIII-positive tumors.


Subject(s)
Antineoplastic Agents/administration & dosage , Brain Neoplasms/drug therapy , ErbB Receptors/metabolism , Glioblastoma/drug therapy , Signal Transduction/drug effects , Tyrphostins/administration & dosage , Animals , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Cell Line, Tumor , Enzyme Inhibitors/administration & dosage , Focal Adhesions/drug effects , Focal Adhesions/metabolism , Glioblastoma/metabolism , Glioblastoma/pathology , Humans , Janus Kinase 2/metabolism , Mice , Mice, Nude , Neoplasm Invasiveness , STAT3 Transcription Factor/metabolism
15.
Mol Cancer Res ; 12(10): 1388-97, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24916103

ABSTRACT

UNLABELLED: Alterations of polycomb group (PcG) genes directly modulate the trimethylation of histone H3 lysine 27 (H3K27me3) and may thus affect the epigenome of hepatocellular carcinoma (HCC), which is crucial for controlling the HCC cell phenotype. However, the extent of downstream regulation by PcGs in HCC is not well defined. Using cDNA microarray analysis, we found that the target gene network of PcGs contains well-established genes, such as cyclin-dependent kinase inhibitors (CDKN2A), and genes that were previously undescribed for their regulation by PcG, including E2F1, NOTCH2, and TP53. Using chromatin immunoprecipitation assays, we demonstrated that EZH2 occupancy coincides with H3K27me3 at E2F1 and NOTCH2 promoters. Interestingly, PcG repress the expression of the typical tumor suppressor TP53 in human HCC cells, and an increased level of PcG was correlated with the downregulation of TP53 in certain HCC specimens. Unexpectedly, we did not find obvious H3K27me3 modification or an EZH2 binding signal at the TP53 promoters, suggesting that PcG regulates TP53 expression in an H3K27me3-independent manner. Finally, the reduced expression of PcGs effectively blocked the aggressive signature of liver cancer cells in vitro and in vivo. IMPLICATIONS: Taken together, our results establish the functional and mechanistic significance of certain gene regulatory networks that are regulated by PcGs in HCC.


Subject(s)
Carcinoma, Hepatocellular/genetics , Gene Expression Regulation, Neoplastic , Histones/metabolism , Liver Neoplasms/genetics , Lysine/metabolism , Polycomb Repressive Complex 2/metabolism , Repressor Proteins/metabolism , Animals , Carcinoma, Hepatocellular/pathology , Cell Movement , Cell Proliferation , Enhancer of Zeste Homolog 2 Protein , Gene Knockdown Techniques , Humans , Liver Neoplasms/pathology , Methylation , Mice, Nude , Signal Transduction , Transcription, Genetic , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Xenograft Model Antitumor Assays
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