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1.
Dalton Trans ; 51(40): 15330-15338, 2022 Oct 18.
Article in English | MEDLINE | ID: mdl-36134906

ABSTRACT

Overexpressed HOCl in tumors can behave as an activator for imaging-guided precision therapy. Herein, a new kind of HOCl-activated molecular platform has been developed aiming at the integration of detection, imaging, and anticancer functions. The design strategy uses a five-membered heterocyclic ring to bridge the fluorescent fluorescein part (FL) and the anticancer ferrocene part (Fc). Three derivatives, namely FL-Fc, FL-NP-Fc and FL-TEG-Fc, were designed with different grafted chains on the fluorescein mother to modulate the hydrophilic and biocompatible capacity. In these molecular platforms, the ferrocene unit serves as the fluorescence emission quencher and masked prodrug. These three could respond to HOCl with good selectivity and sensitivity, showing a turn-on fluorescence signal and anticancer efficacy. FL-TEG-Fc with the highest sensitivity (6.5 × 10-6 M) was successfully used for imaging endogenous HOCl in AGS cells, in which it presented strong toxicity IC50 = 9.5 ± 0.3 µM. The mechanistic study revealed that the five-membered heterocyclic ring of FL-TEG-Fc was broken specifically and effectively by HOCl to release strongly fluorescent fluorescein and a bioactive ferrocene derivative; the obtained ferrocene derivative further generated cytotoxic ˙OH through a Fenton-like reaction. This study provides a potential theranostic strategy against HOCl-overexpressing cancers.


Subject(s)
Fluorescent Dyes , Prodrugs , Ferrous Compounds , Fluorescein/pharmacology , Fluorescent Dyes/pharmacology , Hypochlorous Acid , Metallocenes/pharmacology , Prodrugs/pharmacology
2.
Onco Targets Ther ; 13: 3943-3952, 2020.
Article in English | MEDLINE | ID: mdl-32440157

ABSTRACT

PURPOSE: To observe the clinicopathological, immunohistochemical, and molecular genetic features of epithelioid glioblastoma (E-GBM), and identify tumor-associated prognostic factors. PATIENTS AND METHODS: The clinical and radiological data of fifteen cases of E-GBM were collected, and their pathological, immunohistochemical, and molecular features were examined. A 1p/19q analysis via FISH, MGMT promoter methylation by MS-PCR, and IDH1 and BRAF V600E mutation analysis by HRM-PCR were performed. The level of EZH2 expression was valuated by immunohistochemistry in 15 E-GBM cases, and the prognostic factors were analyzed in E-GBM patients. Fifteen non-E-GBM cases were used as a control. RESULTS: The fifteen cases of E-GBM included twelve males and three females, with fourteen cases supratentorially located. Headache was the main symptom. Microscopy revealed that the tumors were composed of epithelioid cells and some rhabdoid cells. The epithelioid and rhabdoid cells displayed focal discohesion, scant intervening neuropil, a distinct cell membrane, eosinophilic cytoplasm, and a laterally positioned nucleus. Most tumors showed high mitosis, zonal necrosis, and microvascular hyperplasia. Immunohistochemical findings included epithelioid cells positive for GFAP, vimentin, nestin, S-100, and INI-1. The molecular findings included no deletions of 1p/19q, EGFR amplifications, or IDH1 mutations in any case, a methylated MGMT promoter in 46.7% (7/15) cases, and a BRAFV600E mutation in 46.7% (7/15) cases. EZH2 overexpression occurred in 60.0% (9/15) of E-GBM cases. E-GBM patients with OS (≤12 months) exhibited extensive necrosis (6/6), EZH2 overexpression (6/6), MGMT promoter unmethylation (5/6), BRAFV600E mutation (3/6), and treatment (surgery4/6). E-GBM patients with OS (>12 months) exhibited focal or limited necrosis, low or negative EZH2 expression, MGMT promoter methylation (2/3), BRAFV600E mutation (3/3), and treatment (surgery+radiotherapy/chemo-radiotherapy, 2/3). CONCLUSION: E-GBM was a rare variant of glioblastoma, with histological epithelioid features and poor prognosis. Extensive necrosis, MGMT promoter unmethylation, EZH2 overexpression, and lack of adjuvant chemo-radiotherapy may indicate a poor prognosis.

3.
Inorg Chem ; 59(13): 9177-9187, 2020 Jul 06.
Article in English | MEDLINE | ID: mdl-32447953

ABSTRACT

By taking advantage of the efficient Förster resonance energy transfer (FRET) between near-infrared (NIR)-responsive lanthanide-doped upconversion nanoparticles (UCNPs) and Fenton reagent ferrocenyl compounds (Fc), a series of Fc-UCNPs was designed by functionalizing NaYF4:Yb,Tm nanoparticles with Fc1-Fc5 via surface-coordination chemistry. Fc-UCNP-Lipo nanosystems were then constructed by encapsulating Fc-UCNP inside liposomes for efficient delivery. Fc-UCNP can effectively release ·OH via a NIR-promoted Fenton-like reaction. In vitro and in vivo studies of Fc1-UCNP-Lipo confirmed the preferential accumulation in a tumor site followed by an enhanced uptake of cancer cells. After cellular internalization, the released Fc1-UCNP can effectively promote ·OH generation for tumor growth suppression. Such a Fc1-UCNP-Lipo nanosystem exhibits advantages such as easy fabrication, low drug dosage, and no ferrous ion release.


Subject(s)
Antineoplastic Agents/therapeutic use , Ferrous Compounds/therapeutic use , Metal Nanoparticles/therapeutic use , Metallocenes/therapeutic use , Neoplasms/drug therapy , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/radiation effects , Cell Line, Tumor , Drug Carriers/chemistry , Female , Ferrous Compounds/chemistry , Ferrous Compounds/radiation effects , Humans , Infrared Rays , Liposomes/chemistry , Metal Nanoparticles/chemistry , Metal Nanoparticles/radiation effects , Metallocenes/chemistry , Metallocenes/radiation effects , Mice, Inbred BALB C , Neoplasms/pathology , Terbium/chemistry , Terbium/radiation effects , Xenograft Model Antitumor Assays , Yttrium/chemistry , Yttrium/radiation effects
4.
Cancer Lett ; 430: 11-24, 2018 08 28.
Article in English | MEDLINE | ID: mdl-29746925

ABSTRACT

Tumor growth is fueled by subset of cells with stem cell properties (Cancer stem cells, CSCs). While persistent activation of Wnt/ß-catenin signaling confers CSC properties, it remains unclear how epigenetic modifications regulate Wnt target genes to dictate their self-renewal. Here, we report a novel Wnt-responsive epigenetic switch for CSC maintenance through activating the stem cell transcription factor ASCL2 in gastric carcinoma (GC). We characterize ASCL2-expressing (ASCL2+) GC cells as a subset of Wnt-responsive CSCs that depend on ASCL2 for self-renewal. High-throughput RNAi screening uncovers that the histone methyltransferase SMYD3 determines H3K4me3 status at the ASCL2 locus to promote ASCL2 expression. Moreover, SMYD3 may be transcriptionally activated by the ß-catenin/TCF4 complex, indicating that the SMYD3-ASCL2 axis may be an integral component of Wnt signaling. Consistently, SMYD3 maintains self-renewal and tumorigenicity of ASCL2+ CSCs largely through inducing ASCL2. Clinically, overexpression of SMYD3 and ASCL2 are associated with malignant progression and poor patient outcomes in GC. Together, these findings define a Wnt-responsive CSC pathway that could be exploited to identify essential regulators of the signaling output, and reveal SMYD3 as an epigenetic target for eliminating CSCs in human cancers.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/genetics , Carcinoma/genetics , Gene Expression Regulation, Neoplastic , Histone-Lysine N-Methyltransferase/metabolism , Stomach Neoplasms/genetics , Basic Helix-Loop-Helix Transcription Factors/metabolism , Carcinogenesis/genetics , Carcinoma/mortality , Carcinoma/pathology , Cell Line, Tumor , Cell Self Renewal/genetics , Epigenesis, Genetic , Female , Gene Knockdown Techniques , Histone-Lysine N-Methyltransferase/genetics , Histones/metabolism , Humans , Male , Middle Aged , Neoplastic Stem Cells/metabolism , RNA, Small Interfering/metabolism , Stomach/pathology , Stomach Neoplasms/mortality , Stomach Neoplasms/pathology , Survival Analysis , Wnt Proteins/metabolism , Wnt Signaling Pathway/genetics , beta Catenin/genetics , beta Catenin/metabolism
5.
Cell Physiol Biochem ; 43(5): 2133-2142, 2017.
Article in English | MEDLINE | ID: mdl-29065410

ABSTRACT

BACKGROUND/AIMS: Neurotensin (NTS), an intestinal hormone, is profoundly implicated in cancer progression through binding its primary receptor NTSR1. The conserved Wnt/ß-Catenin pathway regulates cell proliferation and differentiation via activation of the ß-catenin/T-cell factor (TCF) complex and subsequent modulation of a set of target genes. In this study, we aimed to uncover the potential connection between NTS/NTSR1 signaling and Wnt/ß-Catenin pathway. METHODS: Genetic silencing, pharmacological inhibition and gain-of-function studies as well as bioinformatic analysis were performed to uncover the link between NTS/ NTSR1 signaling and Wnt/ß-Catenin pathway. Two inhibitors were used in vivo to evaluate the efficiency of targeting NTS/NTSR1 signaling or Wnt/ß-Catenin pathway. RESULTS: We found that NTS/NTSR1 induced the activation of mitogen-activated protein kinase (MAPK) and the NF-κB pathway, which further promoted the expression of Wnt proteins, including Wnt1, Wnt3a and Wnt5a. Meanwhile, the mRNA and protein expression levels of NTSR1 were increased by the Wnt pathway activator Wnt3a and decreased by the Wnt inhibitor iCRT3 in glioblastoma cells. Furthermore, pharmacological inhibition of NTS/NTSR1 or Wnt/ß-Catenin signaling suppressed tumor growth in vitro and in vivo. CONCLUSION: These results reveal a positive feedback loop between NTS/NTSR1 and Wnt/ß-Catenin signaling in glioblastoma cells that might be important for tumor development and provide potential therapeutic targets for glioblastoma.


Subject(s)
Glioblastoma/metabolism , Receptors, Neurotensin/metabolism , Wnt Proteins/metabolism , beta Catenin/metabolism , Animals , Apoptosis/genetics , Apoptosis/physiology , Blotting, Western , Cell Proliferation/genetics , Cell Proliferation/physiology , Glioblastoma/genetics , Humans , Mice , Mice, Inbred BALB C , Mice, SCID , Real-Time Polymerase Chain Reaction , Receptors, Neurotensin/genetics , Wnt Proteins/genetics , beta Catenin/genetics
6.
Medicine (Baltimore) ; 96(13): e6478, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28353588

ABSTRACT

RATIONALE: Mucosa-associated lymphoid tissue (MALT) lymphoma is a low grade malignant B cell lymphoma which occurs mainly in the organs having mucosal layer. Though gastrointestinal tract is the most commonly involved extranodal site, primary esophageal MALT lymphoma is very rare with less than 20 cases reported in literature. PATIENT CONCERNS: A 75-year-old man was referred to our hospital for evaluation of dysphagia. Endoscopy revealed a submucosal tumor located in the middle and lower third of esophagus. CT chest and endoscopic ultrasound revealed a 15.5 × 5.9 × 4.0 cm well circumscribed submucosa esophageal tumor. Test for serum antibody against H. pylori was negative. Due to the large tumor size, patient underwent surgical resection. Histological examination showed a submucosal tumor consisting of multiple nodules of varying sizes with intact covering squamous epithelium. The nodules were mainly composed of diffusely and monoclonal proliferating centrocyte-like or monocyte-like cells. Follicular colonizations were observed without lymphoepithelial lesions. The tumor cells were diffusely positive for CD20, PAX-5, Bcl-2 and follicular dendritic cells were positive for CD21, CD23. Monoclonal gene rearrangement was positive for immunoglobulin heavy chain gene, Kappa light chain gene and Lambda light chain gene. DIAGNOSES: Based on these findings, final diagnosis of esophageal MALT lymphoma was made. OUTCOMES: At 8 month follow up, no recurrence or metastases was detected. LESSONS: Esophageal MALT lymphoma is a rare disease with definitive diagnosis possible only after histopathological examination. It carries good prognosis due to low malignant potential.


Subject(s)
Esophageal Mucosa/pathology , Esophageal Neoplasms/pathology , Lymphoma, B-Cell, Marginal Zone/pathology , Aged , Humans , Male
7.
J Zhejiang Univ Sci ; 5(12): 1543-7, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15547962

ABSTRACT

Fe (III)-catalyzed ozonation yielded better degradation rate and extent of COD (Chemical Oxygen Demand) or oxalic acid as compared with oxidation by ozone alone. Two parameters with strong effects on the efficiency of ozonation are pH of the solution and the catalyst (Fe(3+)) dosage. The existence of a critical pH value determining the catalysis of Fe (III) in acid conditions was observed in phenol and oxalic acid systems. The best efficiency of catalysis was obtained at a moderate concentration of the catalyst. A reasonable mechanism of Fe (III)-catalyzed ozonation of phenol was obtained based on the results and literature.


Subject(s)
Bioreactors , Iron/chemistry , Ozone/chemistry , Phenol/chemistry , Phenol/isolation & purification , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Catalysis , Hydrogen-Ion Concentration , Kinetics , Oxalic Acid/chemistry , Oxidation-Reduction
8.
Chemosphere ; 56(10): 889-94, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15268954

ABSTRACT

Electro-coagulation was used to treat refectory wastewater with high oil and grease contents. Different operational conditions were examined, including pH, current density, reaction time, conductivity, electrode distance and inlet concentration. The optimum current density was 10-14 A m(-2) within 30 min depending on the wastewater properties tested. Conductivity had little effect on the treatment efficiency. Although the addition of extra salts (e.g., sodium chloride) to the wastewater did not help increase the pollutant removal efficiency, it could save the power consumption significantly. The COD(Cr) and oil removal efficiency descended with increasing electrode distance. The optimal electrode distance was determined to be 10 mm for this equipment in consideration of the treatment cost and efficiency together. The pH effect on the performance of the electro-coagulation process was not very significant in the range of 3-10. The removal efficiency of oil and COD(Cr) under normal condition exceeded 95% and 75%, respectively.


Subject(s)
Electrocoagulation/methods , Petroleum , Waste Disposal, Fluid/methods , Water Pollutants, Chemical , Electric Conductivity , Electrodes , Hydrogen-Ion Concentration , Time Factors
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