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1.
Phytother Res ; 36(5): 2116-2126, 2022 May.
Article in English | MEDLINE | ID: mdl-35229911

ABSTRACT

The extracts from Psoralea corylifolia Linn. (P. corylifolia) seeds have been shown to display antitumor activity. To date, the prospects of this plant and its active compounds in the treatment of non-small-cell lung cancer (NSCLC) have not been thoroughly studied. In this study, we identified a novel psorachromene compound that displays selective cytotoxic effects on all NSCLC cells tested, including NSCLC cells harboring epidermal growth factor receptor (EGFR) activation mutants (H1975L858R/T790M and H1975-MS35L858R/T790M/C797S ). Psorachromene induces G1 arrest in NSCLC cells harboring wild-type EGFR but induces apoptosis in NSCLC cells harboring activating EGFR mutations. Psorachromene inhibits activated EGFR signaling and kinase activity and suppresses tumor growth of implanted H1975-MS35L858R/T790M/C797S cells in nude mice. Molecular docking analysis revealed that psorachromene could form stronger bonds with mutant EGFR than wild-type EGFR, which might account for the greater cytotoxic effects observed in NSCLC cells harboring activating EGFR mutations (H1975 and H1975-MS35) than wild-type EGFR (A549). In conclusion, it is suggested that psorachromene is an attractive agent to be further explored for its use in the treatment of NSCLC patients harboring EGFR L858R/T790M/C797S.


Subject(s)
Antineoplastic Agents , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Apoptosis , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , ErbB Receptors/genetics , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Mice , Mice, Nude , Molecular Docking Simulation , Mutation , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use
2.
Biomolecules ; 11(9)2021 08 25.
Article in English | MEDLINE | ID: mdl-34572484

ABSTRACT

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are approved treatments for non-small-cell lung cancer (NSCLC) patients harboring activating EGFR mutations. The EGFR C797S mutation is one of the known acquired-resistance mutations to the latest third-generation TKIs. At present, there are no clear options for treating patients who acquire resistance to third-generation TKIs. The acquisition of the EGFR C797S mutation was shown to upregulate the expression of AXL, a receptor tyrosine kinase of the TAM (TYRO3-AXL-MER) family, and the suppression of AXL is effective in reducing the growth of NSCLC cells harboring EGFR C797S. As quercetin was recently shown to inhibit AXL, quercetin may be effective in treating NSCLC cells harboring the EGFR C797S mutation. In this work, the cytotoxic effects of quercetin and its ability to inhibit tumor growth were examined in TKI-resistant NSCLC cells harboring the EGFR C797S mutation. We demonstrated that quercetin exhibited potent cytotoxic effects on NSCLC cells harboring the EGFR C797S mutation by inhibiting AXL and inducing apoptosis. Quercetin inhibited the tumor growth of xenografted NSCLC cells harboring the EGFR C797S mutation and appeared to act synergistically with brigatinib to inhibit of tumor growth in vivo. In summary, herein, we revealed that quercetin is an effective inhibitor for the treatment of non-small-cell lung cancer harboring the EGFR C797S mutation.


Subject(s)
ErbB Receptors/genetics , Lung Neoplasms/genetics , Mutation/genetics , Quercetin/pharmacology , Animals , Apoptosis/drug effects , Autophagy/drug effects , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Clone Cells , Down-Regulation/drug effects , Humans , Lung Neoplasms/pathology , Mice, Inbred BALB C , Mice, Nude , Organophosphorus Compounds/pharmacology , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , Pyrimidines/pharmacology , Quercetin/chemistry , Receptor Protein-Tyrosine Kinases/genetics , Receptor Protein-Tyrosine Kinases/metabolism , Axl Receptor Tyrosine Kinase
3.
Cancer Res ; 81(15): 4094-4109, 2021 08 01.
Article in English | MEDLINE | ID: mdl-34145039

ABSTRACT

ENO1 (α-enolase) expression is significantly correlated with reduced survival and poor prognosis in many cancer types, including lung cancer. However, the function of ENO1 in carcinogenesis remains elusive. In this study, we found that high expression of ENO1 is present in metastatic lung cancer cell lines and malignant tumors and is associated with poor overall survival of patients with lung cancer. Knockdown of ENO1 decreased cancer cell proliferation and invasiveness, whereas overexpression of ENO1 enhanced these processes. Moreover, ENO1 expression promoted tumor growth in orthotopic models and enhanced lung tumor metastasis in tail-vein injection models. These effects were mediated by upregulation of mesenchymal markers N-cadherin and vimentin and the epithelial-to-mesenchymal transition regulator SLUG, along with concurrent downregulation of E-cadherin. Mechanistically, ENO1 interacted with hepatocyte growth factor receptor (HGFR) and activated HGFR and Wnt signaling via increased phosphorylation of HGFR and the Wnt coreceptor LRP5/6. Activation of these signaling axes decreased GSK3ß activity via Src-PI3K-AKT signaling and inactivation of the ß-catenin destruction complex to ultimately upregulate SLUG and ß-catenin. In addition, we generated a chimeric anti-ENO1 mAb (chENO1-22) that can decrease cancer cell proliferation and invasion. chENO1-22 attenuated cancer cell invasion by inhibiting ENO1-mediated GSK3ß inactivation to promote SLUG protein ubiquitination and degradation. Moreover, chENO1-22 prevented lung tumor metastasis and prolonged survival in animal models. Taken together, these findings illuminate the molecular mechanisms underlying the function of ENO1 in lung cancer metastasis and support the therapeutic potential of a novel antibody targeting ENO1 for treating lung cancer. SIGNIFICANCE: This study shows that ENO1 promotes lung cancer metastasis via HGFR and WNT signaling and introduces a novel anti-ENO1 antibody for potential therapeutic use in lung cancer.


Subject(s)
Lung Neoplasms/genetics , Phosphopyruvate Hydratase/metabolism , Proto-Oncogene Proteins c-met/metabolism , Wnt Signaling Pathway/genetics , Animals , Epithelial-Mesenchymal Transition , Female , Humans , Mice , Mice, Inbred NOD , Neoplasm Metastasis
4.
J Control Release ; 324: 482-492, 2020 08 10.
Article in English | MEDLINE | ID: mdl-32497570

ABSTRACT

Lung cancer is the primary cause of cancer-related death worldwide. 85%-90% of cases are non-small cell lung cancer (NSCLC) which characteristically exhibits altered epidermal growth factor receptor (EGFR) signaling is a major driver pathway. Unfortunately, therapeutic outcomes in treating NSCLC are compromised by the emergence of drug resistance in response to EGFR-tyrosine kinase inhibitor (TKI) targeted therapy due to the acquired resistance mutation EGFR T790M or activation of alternative pathways. There is current need for a new generation of TKIs to be developed to treat EGFR-TKI-resistant NSCLC. To overcome the above problems and improve clinical efficacy, nanotechnology with targeting abilities and sustained release has been proposed for EGFR-TKI-resistant NSCLC treatment and has already achieved success in in vitro or in vivo models. In this review, we summarize and illustrate representative nano-formulations targeting EGFR-TKI-resistant NSCLC. The described advances may pave the way to better understanding and design of nanocarriers and multifunctional nanosystems for efficient treatment for drug resistant NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Carcinoma, Non-Small-Cell Lung/drug therapy , Drug Resistance, Neoplasm , ErbB Receptors/genetics , Humans , Lung Neoplasms/drug therapy , Mutation , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use
5.
Oncogenesis ; 9(4): 40, 2020 Apr 22.
Article in English | MEDLINE | ID: mdl-32321917

ABSTRACT

The aberrant subcellular translocation and distribution of epidermal growth factor receptor (EGFR) represent a major yet currently underappreciated cancer development mechanism in non-small cell lung cancer (NSCLC). In this study, we investigated the subcellular interactome of EGFR by using a spectral counting-based approach combined with liquid chromatography-tandem mass spectrometry to understand the associated protein networks involved in the tumorigenesis of NSCLC. A total of 54, 77, and 63 EGFR-interacting proteins were identified specifically in the cytosolic, mitochondrial, and nuclear fractions from a NSCLC cell line, respectively. Pathway analyses of these proteins using the KEGG database shown that the EGFR-interacting proteins of the cytosol and nucleus are involved in the ribosome and spliceosome pathways, respectively, while those of the mitochondria are involved in metabolizing propanoate, fatty acid, valine, leucine, and isoleucine. A selected nuclear EGFR-interacting protein, hnRNP A3, was found to modulate the accumulation of nuclear EGFR. Downregulation of hnRNP A3 reduced the nuclear accumulation of EGFR, and this was accompanied by reduced tumor growth ability in vitro and in vivo. These results indicate that variations in the subcellular translocation and distribution of EGFR within NSCLC cells could affect tumor progression.

6.
J Biomed Sci ; 27(1): 1, 2020 Jan 02.
Article in English | MEDLINE | ID: mdl-31894001

ABSTRACT

It has been more than three decades since the first monoclonal antibody was approved by the United States Food and Drug Administration (US FDA) in 1986, and during this time, antibody engineering has dramatically evolved. Current antibody drugs have increasingly fewer adverse effects due to their high specificity. As a result, therapeutic antibodies have become the predominant class of new drugs developed in recent years. Over the past five years, antibodies have become the best-selling drugs in the pharmaceutical market, and in 2018, eight of the top ten bestselling drugs worldwide were biologics. The global therapeutic monoclonal antibody market was valued at approximately US$115.2 billion in 2018 and is expected to generate revenue of $150 billion by the end of 2019 and $300 billion by 2025. Thus, the market for therapeutic antibody drugs has experienced explosive growth as new drugs have been approved for treating various human diseases, including many cancers, autoimmune, metabolic and infectious diseases. As of December 2019, 79 therapeutic mAbs have been approved by the US FDA, but there is still significant growth potential. This review summarizes the latest market trends and outlines the preeminent antibody engineering technologies used in the development of therapeutic antibody drugs, such as humanization of monoclonal antibodies, phage display, the human antibody mouse, single B cell antibody technology, and affinity maturation. Finally, future applications and perspectives are also discussed.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Autoimmune Diseases/drug therapy , Communicable Diseases/drug therapy , Metabolic Diseases/drug therapy , Neoplasms/drug therapy , Humans , United States , United States Food and Drug Administration
7.
Pediatr Neonatol ; 61(3): 311-317, 2020 06.
Article in English | MEDLINE | ID: mdl-31980413

ABSTRACT

BACKGROUND: Graves disease (GD) is the most common cause of thyrotoxicosis in children and adolescents, accounting for 15% of all thyroid diseases during childhood. Anti-thyroid drugs (ATD) are recommended as the first-line treatment in children and adolescents. However, the remission rate is lower in children than in adults, and the optimal treatment duration and favorable factors associated with remission remain unknown. We aimed to investigate long-term outcomes of pediatric GD patients receiving ATD. METHODS: We retrospectively reviewed medical charts of 396 GD subjects from 1985 to 2017 at MacKay Children's Hospital. Ninety-six patients were excluded from the analyses, including 71 patients followed for less than one year, 6 patients who received radioactive therapy and 19 patients who received surgery. The remaining 300 patients initially treated with ATD and followed up for more than 1 year constituted our study population. RESULTS: The 300 patients comprised 257 (85.7%) females and 43 (14.3%) males. Their median age at diagnosis was 11.6 (range 2.7-17.8) years with 11 patients (3.7%) younger than 5 years. Their median follow-up period was 4.7 (range 1.1-23.9) years. Overall, 122 patients achieved the criteria for discontinuing ATD treatment, and seventy-nine (39.9%) patients achieved remission, with a median follow-up period of 5.3 (range 1.5-20.1) years. Patients in the remission group were more likely to be aged <5 years (remission vs. relapse vs. ongoing ATD; 11.4 vs. 0 vs. 2.6%, P = 0.02), less likely to have a family history of thyroid disease (24.1 vs. 42.1 vs. 52.6%, P = 0.001), and had lower TSH receptor antibody (TRAb) levels (42.8 vs. 53.6 vs. 65.1%, P = 0.02) at the time of diagnosis. CONCLUSION: Long-term ATD remains an effective treatment option for GD in children. Pediatric GD patients aged <5 years, having no family history of thyroid disease and having initial lower TRAb levels were more likely to achieve remission.


Subject(s)
Antithyroid Agents/therapeutic use , Graves Disease/drug therapy , Adolescent , Child , Child, Preschool , Female , Graves Disease/genetics , Humans , Male , Retrospective Studies
8.
ACS Nano ; 12(10): 9894-9902, 2018 10 23.
Article in English | MEDLINE | ID: mdl-30277747

ABSTRACT

Solid tumors characteristically display higher levels of lactate production due to anaerobic metabolism of glucose. Meanwhile, the U.S. Food and Drug Administration (FDA) has approved virotherapy for use in cancer treatment; however systemic administration remains as a particular challenge. Here we report exploitation of tumor lactate production in designing a hypoxia-responsive carrier, self-assembled from hyaluronic acid (HA) conjugated with 6-(2-nitroimidazole)hexylamine, for localized release of recombinant adeno-associated virus serotype 2 (AAV2). The carrier is loaded with lactate oxidase (LOX) and is permeable to small molecules such as the lactate that accumulates in the tumor. Subsequently, LOX oxidizes the lactate to pyruvate inside the carrier, accompanied by internal lowering of oxygen partial pressure. Bioreduction of the 2-nitroimidazole of the HA conjugated with 6-(2-nitroimidazole)hexylamine converts it into a hydrophilic moiety and electrostatically dissociates the carrier and virus. Efficacious and specific delivery was proven by transduction of a photosensitive protein (KillerRed), enabling significant limitation in tumor growth in vivo with photodynamic therapy. An approximate 2.44-fold reduction in tumor weight was achieved after a 2-week course, compared with control groups. Furthermore, conjugation of the AAV2 with iron oxide nanoparticles ("magnetized" AAV2) facilitated magnetic resonance imaging tracking of the virus in vivo. Taken together, the solid tumor microenvironment promotes bioreduction of the lactate-responsive carrier, providing rapid and specific delivery of AAV2 for light-triggered virotherapy via systemic administration.


Subject(s)
Antineoplastic Agents/pharmacology , Lactic Acid/biosynthesis , Lung Neoplasms/drug therapy , Nanoparticles/metabolism , Parvovirinae/metabolism , Photosensitizing Agents/pharmacology , Tumor Microenvironment/drug effects , Animals , Cell Proliferation/drug effects , Cells, Cultured , Dependovirus , HEK293 Cells , Humans , Lactic Acid/chemistry , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Magnetic Resonance Imaging , Mice , Mice, Inbred BALB C , Mice, Nude , Mixed Function Oxygenases/metabolism , Nanoparticles/chemistry , Parvovirinae/isolation & purification , Photochemotherapy
9.
PLoS One ; 11(4): e0154394, 2016.
Article in English | MEDLINE | ID: mdl-27111218

ABSTRACT

Autoimmune thyroid disease (AITD), including Graves disease (GD) and Hashimoto disease (HD), is an organ-specific autoimmune disease with a strong genetic component. Although the cytotoxic T-lymphocyte-associated protein 4 (CTLA4) polymorphism has been reported to be associated with AITD in adults, few studies have focused on children. The aim of our study was to investigate whether the CTLA4 polymorphisms, including -318C/T (rs5742909), +49A/G (rs231775), and CT60 (rs3087243), were associated with GD and HD in Han Chinese adults and children. We studied 289 adult GD, 265 pediatric GD, 229 pediatric HD patients, and 1058 healthy controls and then compared genotype, allele, carrier, and haplotype frequencies between patients and controls. We found that CTLA4 SNPs +49A/G and CT60 were associated with GD in adults and children. Allele G of +49A/G was significantly associated with GD in adults (odds ratio [OR], 1.50; 95% confidence interval [CI], 1.21-1.84; corrected P value [Pc] < 0.001) and children (OR, 1.42; 95% CI, 1.15-1.77; Pc = 0.002). Allele G of CT60 also significantly increased risk of GD in adults (OR, 1.63; 95% CI, 1.27-2.09; Pc < 0.001) and GD in children (OR, 1.58; 95% CI, 1.22-2.04; Pc < 0.001). Significant linkage disequilibrium was found between +49A/G and CT60 in GD and control subjects (D' = 0.92). Our results showed that CTLA4 was associated with both GD and HD and played an equivalent role in both adult and pediatric GD in Han Chinese population.


Subject(s)
CTLA-4 Antigen/genetics , Genetic Predisposition to Disease , Graves Disease/genetics , Hashimoto Disease/genetics , Polymorphism, Single Nucleotide , Adolescent , Adult , Aged , Alleles , Asian People , CTLA-4 Antigen/immunology , Case-Control Studies , Child , Child, Preschool , Female , Gene Expression , Gene Frequency , Graves Disease/ethnology , Graves Disease/immunology , Graves Disease/pathology , Haplotypes , Hashimoto Disease/ethnology , Hashimoto Disease/immunology , Hashimoto Disease/pathology , Heterozygote , Humans , Linkage Disequilibrium , Male , Middle Aged , Odds Ratio , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/pathology
10.
Taiwan J Obstet Gynecol ; 54(5): 572-9, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26522113

ABSTRACT

OBJECTIVE: Most endometrial carcinomas appear to develop from precursors (e.g., endometrial hyperplasia) that progress for several years. Patients who are ultimately diagnosed with carcinoma often present clinically with complaints of abnormal vaginal bleeding years before diagnosis, which offers an opportunity for early diagnosis and curative treatment. The analysis of DNA methylation may be used as a method for detecting endometrial cancer (EC). To test the potential clinical application of this method, we used quantitative methylation analysis of five genes in a full spectrum of endometrial lesions. MATERIALS AND METHODS: This hospital-based, prospective, case-controlled study was conducted on 68 patients, which included patients who had a normal endometrium (n = 18), hyperplasia of the endometrium (n = 24), and EC (n = 26). Methylation levels of the following genes were determined by using real-time methylation-specific polymerase chain reaction (PCR) amplification: zinc finger protein 177 (ZNF177), collagen type XIV α1 (COL14A1), dihydropyrimidinase-like 4 (DPYSL4), homeobox A9 (HOXA9), transmembrane protein with epidermal growth factor-like and two follistatin-like domains 2 (TMEFF2). The methylation index (MI) cutoff values for the different diagnoses were determined to test the sensitivity and specificity of the method and to generate the receiver operating characteristic (ROC) curves. The Mann-Whitney U test was used to test between-group differences in the MI. RESULTS: The MI of the five genes was significantly higher in EC than the MIs in specimens of hyperplasia of endometrium and normal appearance (p < 0.001). The ROC analysis demonstrated that the sensitivity, specificity, and accuracy for detecting EC were 92.3%, 94.4%, and 95.1%, respectively, for ZNF177; 92.3%, 94.4%, and 95.7%, respectively, for COL14A1; 80.8%, 94.4%, and 81.4%, respectively, for HOXA9; 65.4%, 94.4%, and 89.5%, respectively, for TMEFF2; and 61.5%, 94.4%, and 63.3%, respectively, for DPYSL4. The combined testing of ZNF177 and COL14A1 had the best specificity (100%), but compromised sensitivity (88.5%). CONCLUSION: Promoter methylation of ZNF177, COL14A1, HOXA9, DPYSL4, and TMEFF2 genes is a frequent epigenetic event in EC. Furthermore, the epigenetic hypermethylation of TMEFF2 may be a valuable marker for identifying undetected EC within endometrial hyperplasia.


Subject(s)
Carcinogenesis/genetics , DNA, Neoplasm/analysis , Early Detection of Cancer/methods , Endometrial Neoplasms/genetics , Genes, Neoplasm/genetics , Case-Control Studies , DNA Methylation , Endometrial Neoplasms/diagnosis , Female , Humans , Promoter Regions, Genetic , Prospective Studies , ROC Curve , Real-Time Polymerase Chain Reaction , Taiwan
12.
Nat Commun ; 6: 6456, 2015 Mar 05.
Article in English | MEDLINE | ID: mdl-25739372

ABSTRACT

Anticancer therapies are often compromised by nonspecific effects and challenged by tumour environments' inherent physicochemical and biological characteristics. Often, therapeutic effect can be increased by addressing multiple parameters simultaneously. Here we report on exploiting extravasation due to inherent vascular leakiness for the delivery of a pH-sensitive polymer carrier. Tumours' acidic microenvironment instigates a charge reversal that promotes cellular internalization where endosomes destabilize and gene delivery is achieved. We assess our carrier with an aggressive non-small cell lung carcinoma (NSCLC) in vivo model and achieve >30% transfection efficiency via systemic delivery. Rejuvenation of the p53 apoptotic pathway as well as expression of KillerRed protein for sensitization in photodynamic therapy (PDT) is accomplished. A single administration greatly suppresses tumour growth and extends median animal survival from 28 days in control subjects to 68 days. The carrier has capacity for multiple payloads for greater therapeutic response where inter-individual variability can compromise efficacy.


Subject(s)
Apoptosis/physiology , Carcinoma, Non-Small-Cell Lung/therapy , Gene Transfer Techniques , Green Fluorescent Proteins/metabolism , Photochemotherapy/methods , Tumor Microenvironment/physiology , Tumor Suppressor Protein p53/metabolism , Animals , Cell Line, Tumor , Dimethyl Sulfoxide , Endosomes/metabolism , Glutamates , Humans , Hydrogen-Ion Concentration , In Situ Nick-End Labeling , Indoles , Magnetic Resonance Spectroscopy , Mice , Mice, Inbred BALB C
14.
Elife ; 3: e03638, 2014 Jul 16.
Article in English | MEDLINE | ID: mdl-25030911

ABSTRACT

CTP Synthetase (CtpS) is a universally conserved and essential metabolic enzyme. While many enzymes form small oligomers, CtpS forms large-scale filamentous structures of unknown function in prokaryotes and eukaryotes. By simultaneously monitoring CtpS polymerization and enzymatic activity, we show that polymerization inhibits activity, and CtpS's product, CTP, induces assembly. To understand how assembly inhibits activity, we used electron microscopy to define the structure of CtpS polymers. This structure suggests that polymerization sterically hinders a conformational change necessary for CtpS activity. Structure-guided mutagenesis and mathematical modeling further indicate that coupling activity to polymerization promotes cooperative catalytic regulation. This previously uncharacterized regulatory mechanism is important for cellular function since a mutant that disrupts CtpS polymerization disrupts E. coli growth and metabolic regulation without reducing CTP levels. We propose that regulation by large-scale polymerization enables ultrasensitive control of enzymatic activity while storing an enzyme subpopulation in a conformationally restricted form that is readily activatable.


Subject(s)
Carbon-Nitrogen Ligases/metabolism , Cytidine Triphosphate/biosynthesis , Escherichia coli Proteins/metabolism , Escherichia coli/enzymology , Recombinant Fusion Proteins/metabolism , Carbon-Nitrogen Ligases/chemistry , Carbon-Nitrogen Ligases/genetics , Escherichia coli/chemistry , Escherichia coli/genetics , Escherichia coli Proteins/chemistry , Escherichia coli Proteins/genetics , Gene Expression , Kinetics , Models, Molecular , Mutagenesis, Site-Directed , Protein Multimerization , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics
15.
Biochim Biophys Acta ; 1833(12): 3206-3217, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24018208

ABSTRACT

We have reported previously that LIM homeobox transcription factor 1α (LMX1A) is hypermethylated and functions as a metastasis suppressor in cervical cancer cells. However, the regulation of LMX1A in carcinogenesis has not been reported. We aim to clarify whether specificity protein 1 (Sp1) and enhancer of zeste homolog 2 (EZH2) are involved in the regulation of LMX1A in cervical cancer. First we characterized the LMX1A promoter and used overexpression, knockdown, and reporter assays to show that Sp1 increased LMX1A promoter activity. Next, we used site-directed mutagenesis and electrophoresis mobility shift assays (EMSAs) to demonstrate that Sp1-binding sites were important for Sp1-mediated activation of the LMX1A promoter. Chromatin immunoprecipitation data demonstrated that Sp1 could bind directly to the LMX1A promoter and activate endogenous LMX1A expression in cells pretreated with 5-aza-2'-deoxycytidine (5-aza-dC). Knockdown of EZH2 decreased H3K27me3 histone modification but was insufficient to restore LMX1A expression. To explore the effect of EZH2 on the endogenous LMX1A promoter, we treated EZH2-knockdown cells with 5-aza-dC and trichostatin A (TSA) and then depleted the cells of drugs for 3days. H3K14ac was enriched at the LMX1A promoter in EZH2-knockdown cells and LMX1A mRNA was still expressed. Taken together, these data imply that Sp1 may activate LMX1A expression upon oncogenic stress during cervical cancer development. Moreover, suppression of EZH2 may delay resilencing of LMX1A after the removal of 5-aza-dC and TSA.


Subject(s)
LIM-Homeodomain Proteins/genetics , Polycomb Repressive Complex 2/metabolism , Sp1 Transcription Factor/metabolism , Transcription Factors/genetics , Uterine Cervical Neoplasms/genetics , Azacitidine/pharmacology , Base Sequence , Binding Sites , Cell Line, Tumor , Enhancer of Zeste Homolog 2 Protein , Female , Gene Expression Regulation, Neoplastic/drug effects , Gene Knockdown Techniques , Gene Silencing/drug effects , Histone Deacetylase Inhibitors/pharmacology , Histones/metabolism , Humans , LIM-Homeodomain Proteins/metabolism , Methylation/drug effects , Molecular Sequence Data , Promoter Regions, Genetic/genetics , Protein Binding/genetics , Sp1 Transcription Factor/antagonists & inhibitors , Transcription Factors/metabolism
16.
Cell Mol Biol Lett ; 17(4): 542-8, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22893264

ABSTRACT

Dynamic instability is an essential phenomenon in eukaryotic nuclear division and prokaryotic plasmid R1 segregation. Although the molecular machines used in both systems differ greatly in composition, strong similarities and requisite nuances in dynamics and segregation mechanisms are observed. This brief examination of the current literature provides a functional comparison between prokaryotic and eukaryotic dynamically unstable filaments, specifically ParM and microtubules. Additionally, this mini-review should support the notion that any dynamically unstable filament could serve as the molecular machine driving DNA segregation, but these machines possess auxiliary features to adapt to temporal and spatial disparities in either system.


Subject(s)
Chromosome Segregation , Escherichia coli/metabolism , Eukaryota/metabolism , Cell Division , Cytoskeleton/genetics , Escherichia coli/genetics , Eukaryota/genetics , Microtubules/metabolism
17.
Hepatology ; 56(6): 2277-87, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22767186

ABSTRACT

UNLABELLED: Oncogenic activation of the Wnt/ß-catenin signaling pathway is common in hepatocellular carcinoma (HCC). Our recent studies have demonstrated that SRY (sex determining region Y)-box 1 (SOX1) and secreted frizzled-related proteins are concomitantly promoter-hypermethylated, and this might lead to abnormal activation of the Wnt signaling pathway in HCC. SOX1 encodes a transcription factor involved in the regulation of embryonic development and cell fate determination. However, the expression and functional role of SOX1 in HCC remains unclear. In this study, we confirmed via quantitative methylation-specific polymerase chain reaction that SOX1 was frequently downregulated through promoter hypermethylation in HCC cells and tissues. Overexpression of SOX1 by a constitutive or inducible approach could suppress cell proliferation, colony formation, and invasion ability in HCC cell lines, as well as tumor growth in nonobese diabetic/severe combined immunodeficiency mice. Conversely, knockdown of SOX1 by withdrawal of doxycycline could partially restore cell proliferation and colony formation in HCC cells. We used a T cell factor (TCF)-responsive luciferase reporter assay and western blot analysis to prove that SOX1 could regulate TCF-responsive transcriptional activity and inhibit the expression of Wnt downstream genes. Furthermore, we used glutathione S-transferase pull-down, co-immunoprecipitation, and confocal microscopy to demonstrate that SOX1 could interact with ß-catenin but not with the ß-catenin/TCF complex. Moreover, restoration of the expression of SOX1 induces significant cellular senescence in Hep3B cells. CONCLUSION: Our data show that a developmental gene, SOX1, may function as a tumor suppressor by interfering with Wnt/ß-catenin signaling in the development of HCC.


Subject(s)
Carcinoma, Hepatocellular/genetics , Genes, Tumor Suppressor , Liver Neoplasms/genetics , SOXB1 Transcription Factors/genetics , SOXB1 Transcription Factors/metabolism , Wnt Signaling Pathway , Animals , Anti-Bacterial Agents/pharmacology , Antigens, CD , Cadherins/genetics , Cadherins/metabolism , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Cycle Checkpoints , Cell Proliferation , Cyclin D1/genetics , Cyclin D1/metabolism , Cyclin-Dependent Kinase 4/metabolism , Cyclin-Dependent Kinase 6/metabolism , DNA Methylation , Down-Regulation , Doxycycline/pharmacology , Genes, bcl-1 , Genes, myc , Hep G2 Cells , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Mice , Mice, Inbred NOD , Mice, SCID , Proliferating Cell Nuclear Antigen/metabolism , Promoter Regions, Genetic , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins p21(ras)/metabolism , RNA, Messenger/metabolism , SOXB1 Transcription Factors/drug effects , Snail Family Transcription Factors , Transcription Factors/genetics , Transcription Factors/metabolism
18.
J Pediatr Endocrinol Metab ; 21(7): 665-72, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18780601

ABSTRACT

BACKGROUND: The CTLA4 gene is involved in the activity of T cells. AIM: To determine the association between Graves' disease (GD) susceptibility and CT60 polymorphism of the CTLA4 gene. PATIENTS: 189 children with GD and 620 healthy controls. METHODS: We determined the genotype with restriction fragment length polymorphism and compared results. RESULTS: Genotype G/G was significantly associated with GD (odds ratio [OR] = 1.71, 95% confidence interval [CI] 1.20-2.44, Pc = 0.006); however, allele A could reverse its effect. Allele G was significantly more frequent (OR = 1.61, 95% CI 1.18-2.19, Pc = 0.0049) but allele A (OR = 0.62, 95% CI 0.46-0.85, Pc = 0.0049) and phenotype A (OR = 0.58, 95% CI 0.41-0.83, Pc = 0.006) were less frequent in patients with GD than in controls. CONCLUSION: The CT60 SNP was associated with susceptibility to GD. The G allele increased the risk of GD.


Subject(s)
Antigens, CD/genetics , Graves Disease/epidemiology , Graves Disease/genetics , Polymorphism, Genetic/genetics , Adolescent , Adult , Age of Onset , Alleles , CTLA-4 Antigen , Child , Child, Preschool , DNA/biosynthesis , DNA/genetics , Female , Genotype , Humans , Infant , Male , Odds Ratio , Polymorphism, Restriction Fragment Length , Reverse Transcriptase Polymerase Chain Reaction , T-Lymphocytes/metabolism , Taiwan/epidemiology , Thyroid Function Tests , Thyrotropin/blood , Thyroxine/blood
19.
Acta Paediatr Taiwan ; 48(3): 119-24, 2007.
Article in English | MEDLINE | ID: mdl-17912982

ABSTRACT

BACKGROUND: The incidence of type 1 diabetes (T1D) is increasing rapidly worldwide, predominantly in younger individuals. We developed a checklist of all symptoms of T1D reported in the literature and compared the completeness of the recording of symptoms at initial presentation before and after the checklist was adopted. METHODS: We retrospectively reviewed the records of patients newly diagnosed with T1D from January 1, 1979 through September 30, 2006 to assess the presenting features and test the usefulness of a symptom checklist in evaluating the history on presentation. The checklist was incorporated into the records as of October 1, 1994. RESULTS: Of the 304 patients identified, 130 (43%) had checklists in the charts. There were 146 (48%) boys, 98 (32%) who were diagnosed under the age of 6 years, and 198 (65%) presented with diabetic ketoacidosis (DKA). Records with a checklist noted diabetic symptoms that were subtle and easily ignored more often than records without the checklist. As compared with those diagnosed at an older age, patients diagnosed at < or = 6 years were more likely to be male, have DKA and a shorter symptom duration, and report more episodes of preceding viral infection and dyspnea. Patients with DKA also had a shorter symptom duration. CONCLUSIONS: A diabetic symptom checklist was helpful in identifying clinical diabetic symptoms and signs which were otherwise easily ignored. Younger children were more likely to have a shorter symptom duration and a higher incidence of DKA.


Subject(s)
Diabetes Mellitus, Type 1/diagnosis , Adolescent , Child , Child, Preschool , Diabetes Mellitus, Type 1/complications , Diabetic Ketoacidosis/epidemiology , Female , Humans , Male , Retrospective Studies
20.
Acta Paediatr Taiwan ; 47(4): 187-91, 2006.
Article in English | MEDLINE | ID: mdl-17180786

ABSTRACT

BACKGROUND: Type 2 diabetes mellitus (T2DM) in children and adolescents is increasing in incidence worldwide. It is the leading type of newly diagnosed diabetes in Taiwan among school children. T2DM is associated with metabolic syndrome in adults, so we tried to find out if these metabolic disorders are present in children. METHODS: From 1989 to 2003, 22 children and adolescents were diagnosed with T2DM in our hospital. Their ages ranged from 8.8 to 17.0 (11.7+/-2.3) years; 6 of them were boys. We compared their clinical characteristics with those of 42 healthy and 237 obese children and adolescents. Physical examination was performed and plasma glucose and serum cholesterol, triglycerides, uric acid, creatinine, HDL-cholesterol, and insulin levels were measured and LDL-cholesterol was calculated. Demographic and laboratory data were compared among the T2DM, obese and control groups. RESULTS: The female: male ratio among the patients was 2.7: 1; 18% were overweight and 68% obese, and 64% had acanthosis nigricans. There were no significant differences between the T2DM and obese groups in terms of biochemistry profiles except for the higher plasma glucose in the T2DM group. Children with T2DM had higher levels of cholesterol and triglycerides but lower levels of HDL-cholesterol compared with healthy children. Among obese children without T2DM, the levels of glucose, triglycerides, uric acid, insulin, HOMA-IR were higher than in the healthy group, and HDL-cholesterol levels were lower. CONCLUSIONS: Children with T2DM or obesity should be evaluated for metabolic disorders.


Subject(s)
Diabetes Mellitus, Type 2/metabolism , Metabolic Diseases/etiology , Acanthosis Nigricans/etiology , Adolescent , Body Mass Index , Child , Cholesterol, HDL/blood , Female , Humans , Insulin/blood , Insulin Resistance , Male , Obesity/metabolism
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