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1.
Cell ; 162(3): 580-92, 2015 Jul 30.
Article in English | MEDLINE | ID: mdl-26213385

ABSTRACT

Although it is known that the centrioles play instructive roles in pericentriolar material (PCM) assembly and that the PCM is essential for proper centriole formation, the mechanism that governs centriole-PCM interaction is poorly understood. Here, we show that ATF5 forms a characteristic 9-fold symmetrical ring structure in the inner layer of the PCM outfitting the proximal end of the mother centriole. ATF5 controls the centriole-PCM interaction in a cell-cycle- and centriole-age-dependent manner. Interaction of ATF5 with polyglutamylated tubulin (PGT) on the mother centriole and with PCNT in the PCM renders ATF5 as a required molecule in mother centriole-directed PCM accumulation and in PCM-dependent centriole formation. ATF5 depletion blocks PCM accumulation at the centrosome and causes fragmentation of centrioles, leading to the formation of multi-polar mitotic spindles and genomic instability. These data show that ATF5 is an essential structural protein that is required for the interaction between the mother centriole and the PCM.


Subject(s)
Activating Transcription Factors/metabolism , Centrioles/metabolism , Centrosome/metabolism , Cytoskeleton/metabolism , Down-Regulation , Genomic Instability , HeLa Cells , Humans , Spindle Apparatus/metabolism , Tubulin/metabolism
2.
Semin Cancer Biol ; 83: 377-383, 2022 08.
Article in English | MEDLINE | ID: mdl-34182142

ABSTRACT

The epigenetic regulation of immune response involves reversible and heritable changes that do not alter the DNA sequence. Though there have been extensive studies accomplished relating to epigenetic changes in cancer cells, recent focus has been shifted on epigenetic-mediated changes in the immune cells including T cells, Macrophages, Natural Killer cells and anti-tumor immune responses. This review compiles the most relevant and recent literature related to the role of epigenetic mechanisms including DNA methylation and histone modifications in immune cells of wide range of cancers. We also include recent research with respect to role of the most relevant transcription factors that epigenetically control the anti-tumor immune response. Finally, a statement of future direction that promises to look forward for strategies to improve immunotherapy in cancer.


Subject(s)
Epigenesis, Genetic , Neoplasms , DNA Methylation , Humans , Immunotherapy , Neoplasms/genetics , Neoplasms/therapy
3.
FASEB J ; 36(4): e22250, 2022 04.
Article in English | MEDLINE | ID: mdl-35294071

ABSTRACT

Combination therapy represents an effective therapeutic approach to overcome hepatocellular cancer (HCC) resistance to immune checkpoint blockade (ICB). Based upon previous work demonstrating that nanoliposome C6-ceramide (LipC6) not only induces HCC apoptosis but also prevents HCC-induced immune tolerance, we now investigate the potential of LipC6 in combination with ICB in HCC treatment. We generated orthotopic HCC-bearing mice, which have typical features in common with human patients, and then treated them with LipC6 in combination with the antibodies (Abs) for programmed cell death protein 1 (PD-1) or cytotoxic T-lymphocyte antigen 4 (CTLA4). The tumor growth was monitored by magnetic resonance imaging (MRI) and the intrahepatic immune profiles were checked by flow cytometry in response to the treatments. Realtime PCR (qPCR) was used to detect the expression of target genes. The results show that LipC6 in combination with anti-CTLA4 Ab, but not anti-PD-1 Ab, significantly slowed tumor growth, enhanced tumor-infiltrating CD8+ T cells, and suppressed tumor-resident CD4+ CD25+ FoxP3+ Tregs. Further molecular investigation indicates that the combinational treatment suppressed transcriptional factor Krüppel-like Factor 2 (KLF2), forkhead box protein P3 (FoxP3), and CTLA4. Our studies suggest that LipC6 in combination with anti-CTLA4 Ab represents a novel therapeutic approach with significant potential in activating anti-HCC immune response and suppressing HCC growth.


Subject(s)
Antineoplastic Agents , Carcinoma, Hepatocellular , Liver Neoplasms , Animals , Antineoplastic Agents/pharmacology , CD8-Positive T-Lymphocytes , CTLA-4 Antigen , Carcinoma, Hepatocellular/metabolism , Ceramides , Forkhead Transcription Factors/metabolism , Humans , Liver Neoplasms/metabolism , Mice
4.
Mol Cancer ; 21(1): 73, 2022 03 12.
Article in English | MEDLINE | ID: mdl-35279152

ABSTRACT

BACKGROUND: Circulating tumor cells (CTCs) are liquid biopsies that represent micrometastatic disease and may offer unique insights into future recurrences in non-small cell lung cancer (NSCLC). Due to CTC rarity and limited stability, no stable CTC-derived xenograft (CDX) models have ever been generated from non-metastatic NSCLC patients directly. Alternative strategies are needed to molecularly characterize CTCs and means of potential future metastases in this potentially curable patient group. METHODS: Surgically resected NSCLC primary tumor tissues from non-metastatic patients were implanted subcutaneously in immunodeficient mice to establish primary tumor patient-derived xenograft (ptPDX) models. CTCs were isolated as liquid biopsies from the blood of ptPDX mice and re-implanted subcutaneously into naïve immunodeficient mice to generate liquid biopsy CTC-derived xenograft (CDX) tumor models. Single cell RNA sequencing was performed and validated in an external dataset of non-xenografted human NSCLC primary tumor and metastases tissues. Drug response testing in CDX models was performed with standard of care chemotherapy (carboplatin/paclitaxel). Blockade of MYC, which has a known role in drug resistance, was performed with a MYC/MAX dimerization inhibitor (10058-F4). RESULTS: Out of ten ptPDX, two (20%) stable liquid biopsy CDX mouse models were generated. Single cell RNA sequencing analysis revealed an additional regenerative alveolar epithelial type II (AT2)-like cell population in CDX tumors that was also identified in non-xenografted NSCLC patients' metastases tissues. Drug testing using these CDX models revealed different treatment responses to carboplatin/paclitaxel. MYC target genes and c-MYC protein were upregulated in the chemoresistant CDX model, while MYC/MAX dimerization blocking could overcome chemoresistance to carboplatin/paclitaxel. CONCLUSIONS: To overcome the lack of liquid biopsy CDX models from non-metastatic NSCLC patients, CDX models can be generated with CTCs from ptPDX models that were originally established from patients' primary tumors. Single cell analyses can identify distinct drug responses and cell heterogeneities in CDX tumors that can be validated in NSCLC metastases tissues. CDX models deserve further development and study to discover personalized strategies against micrometastases in non-metastatic NSCLC patients.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Neoplastic Cells, Circulating , Animals , Carboplatin/pharmacology , Carboplatin/therapeutic use , Carcinogenesis , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Disease Models, Animal , Heterografts , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Mice , Neoplastic Cells, Circulating/pathology , Paclitaxel/pharmacology , Paclitaxel/therapeutic use
5.
Curr Issues Mol Biol ; 44(2): 750-763, 2022 Feb 02.
Article in English | MEDLINE | ID: mdl-35723337

ABSTRACT

Non-small-cell lung cancer (NSCLC) accounts for most cancer-related deaths worldwide. Liquid biopsy by a blood draw to detect circulating tumor cells (CTCs) is a tool for molecular profiling of cancer using single-cell and next-generation sequencing (NGS) technologies. The aim of the study was to identify somatic variants in single CTCs isolated from NSCLC patients by targeted NGS. Thirty-one subjects (20 NSCLC patients, 11 smokers without cancer) were enrolled for blood draws (7.5 mL). CTCs were identified by immunofluorescence, individually retrieved, and DNA-extracted. Targeted NGS was performed to detect somatic variants (single-nucleotide variants (SNVs) and insertions/deletions (Indels)) across 65 oncogenes and tumor suppressor genes. Cancer-associated variants were classified using OncoKB database. NSCLC patients had significantly higher CTC counts than control smokers (p = 0.0132; Mann-Whitney test). Analyzing 23 CTCs and 13 white blood cells across seven patients revealed a total of 644 somatic variants that occurred in all CTCs within the same subject, ranging from 1 to 137 per patient. The highest number of variants detected in ≥1 CTC within a patient was 441. A total of 18/65 (27.7%) genes were highly mutated. Mutations with oncogenic impact were identified in functional domains of seven oncogenes/tumor suppressor genes (NF1, PTCH1, TP53, SMARCB1, SMAD4, KRAS, and ERBB2). Single CTC-targeted NGS detects heterogeneous and shared mutational signatures within and between NSCLC patients. CTC single-cell genomics have potential for integration in NSCLC precision oncology.

6.
Inorg Chem ; 61(8): 3736-3745, 2022 Feb 28.
Article in English | MEDLINE | ID: mdl-35175759

ABSTRACT

Constructing high-quality white organic light-emitting diodes (WOLEDs) remains a big challenge because of high demands on the electroluminescence (EL) performance including high efficiency, excellent spectral stability, and low roll-off simultaneously. To achieve effective energy transfer and trap-assisted recombination in the emissive layer, herein, four Ir(III) phosphors, namely, mOMe-Ir-PI (1), pOMe-Ir-PI (2), mOMe-Ir-PB (3), and pOMe-Ir-PB (4), were strategically designed via simple regulation of the substituent moiety and π conjugation of the chelated ligands. Their photophysical and EL properties were systematically investigated. When these phosphors are employed as doped emitters, the monochromic green organic light-emitting diodes not only exhibit a superior performance with the characteristics of 50.2 cd A-1, 39.2 lm W-1, and 15.1%, but also maintain a negligible roll-off ratio of 0.2% at 1000 cd m-2, which are better than those of commercial green Ir(ppy)2acac and Ir(ppy)3 in the same device configuration. Inspired by these outstanding performances, we successfully fabricated the warm WOLED utilizing 2 as a green component, affording a peak efficiency of 42.0 cd A-1, 29.3 lm W-1, and 18.6% and retaining at 39.9 cd A-1, 23.7 lm W-1, and 17.4% even at 1000 cd m-2. The results herein demonstrate the superiority of the molecular design and propose a simple method toward the development of promising Ir(III) phosphors for high-efficiency WOLEDs.

7.
Angew Chem Int Ed Engl ; 61(10): e202113425, 2022 03 01.
Article in English | MEDLINE | ID: mdl-34962678

ABSTRACT

Ultralong organic phosphorescence (UOP) materials glow persistently in the dark, which offers new exciting possibilities in the fields of anti-counterfeiting, photoelectric devices and biological imaging. However, the development of single-component UOP materials remains a great challenge. Herein, we develop a single component organic supramolecular zipper system with a lifetime up to 0.77 s. Owing to the introduction of a pyrazole ring into the diphenylsulfone group, the "V" shaped molecules were artfully self-assembled into supramolecular zippers via π-π and C-H⋅⋅⋅π interactions, that is not only of significance in highly efficient generation of triplet excitons but also facilitates a Dexter energy transfer process within supramolecular zippers, that are responsible for alleviating radiative and non-radiative deactivation decay of triplet excitons, to finally boost the UOP. This finding not only gives a new set of guidelines for the design of single-component UOP molecules but also reveals the UOP mechanism from a new perspective.

8.
Inorg Chem ; 60(6): 3741-3748, 2021 Mar 15.
Article in English | MEDLINE | ID: mdl-33641331

ABSTRACT

Mechanochromic luminescent (MCL) materials are promising in pressure sensors, security papers, photoelectric devices and optical data recording. Although some kinds of MCL-active iridium(III) complexes with various soft substituent functional ligands (e.g., dendritic carbazole, flexible chains, and Schiff base ligands) were reported, the MCL mechanism is still not clear and mainly ascribes to the physical phase transformations from crystalline state to amorphous state in response to force stimulus at present stage, and deserves further study in order to obtain more intelligent MCL materials. Herein, two new iridium(III) complex isomers are tactfully constructed and show distinctly opposite MCL properties in spite of the same physical phase transformations happening on them. The absolutely out of the ordinary MCL mechanism has been presented on account of molecular level for the first time via the comparative study of photophysical properties based on isomers 1 and 2 with the help of crystal structure analysis, room/low temperature emission spectra, NMR, PXRD, and TD-DFT calculations. All of these results suggest that the emitting state dominated by the triplet charge transfer excited state (3CT) plays a key role in achieving mechanochromic luminescence in iridium(III) complex systems.

9.
Chem Soc Rev ; 49(3): 765-838, 2020 Feb 10.
Article in English | MEDLINE | ID: mdl-31942586

ABSTRACT

The development of metal complexes for optoelectronic applications is a fertile area of research. In contrast to the rigorous development of mononuclear metal complexes, dinuclear species have been less well studied and their fundamental chemistry and applications are under-explored. However, dinuclear species present special properties and functions compared with mononuclear species as a consequence of tuning the bridging ligands, the cyclometalated ligands or the two metal centers. More recently, dinuclear species have enabled important breakthroughs in the fields of OLEDs, photocatalytic water splitting and CO2 reduction, DSPEC, chemosensors, biosensors, PDT, smart materials and so on. Here we present an overview of recent developments of dinuclear metal complexes, their multifunctional properties and their various applications. The relationship between structure and property of dinuclear species and important factors which influence device performance are discussed. Finally, we illustrate some challenges and opportunities for future research into dinuclear metal complexes. This review aims to provide an up-to-date summary and outlook of functional dinuclear metal complexes and to stimulate more researchers to contribute to this exciting interdisciplinary field.

10.
Int J Mol Sci ; 22(20)2021 Oct 13.
Article in English | MEDLINE | ID: mdl-34681695

ABSTRACT

Dietary change leads to a precipitous increase in non-alcoholic fatty liver disease (NAFLD) from simple steatosis to the advanced form of non-alcoholic steatohepatitis (NASH), affecting approximately 25% of the global population. Although significant efforts greatly advance progress in clarifying the pathogenesis of NAFLD and identifying therapeutic targets, no therapeutic agent has been approved. Astaxanthin (ASTN), a natural antioxidant product, exerts an anti-inflammation and anti-fibrotic effect in mice induced with carbon tetrachloride (CCl4) and bile duct ligation (BDL); thus, we proposed to further investigate the potential effect of ASTN on a diet-induced mouse NASH and liver fibrosis, as well as the underlying cellular and molecular mechanisms. By treating pre-development of NASH in mice induced with a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD), we have demonstrated that oral administration ASTN preventively ameliorated NASH development and liver fibrosis by modulating the hepatic immune response, liver inflammation, and oxidative stress. Specifically, ASTN treatment led to the reduction in liver infiltration of monocyte-derived macrophages, hepatic stellate cell (HSC) activation, oxidative stress response, and hepatocyte death, accompanied by the decreased hepatic gene expression of proinflammatory cytokines such as TNF-α, TGF-ß1, and IL-1ß. In vitro studies also demonstrated that ASTN significantly inhibited the expression of proinflammatory cytokines and chemokine CCL2 in macrophages in response to lipopolysaccharide (LPS) stimulation. Overall, in vivo and in vitro studies suggest that ASTN functions as a promising therapeutic agent to suppress NASH and liver fibrosis via modulating intrahepatic immunity.


Subject(s)
Non-alcoholic Fatty Liver Disease/drug therapy , Animals , Chemokine CCL2/metabolism , Cytokines/metabolism , Diet, High-Fat , Disease Models, Animal , Fibroblast Growth Factor 2/metabolism , Hepatic Stellate Cells/cytology , Hepatic Stellate Cells/metabolism , Lipopolysaccharides/pharmacology , Liver/metabolism , Liver/pathology , Liver Cirrhosis/chemically induced , Liver Cirrhosis/prevention & control , Macrophages/cytology , Macrophages/drug effects , Macrophages/immunology , Macrophages/metabolism , Male , Mice , Mice, Inbred C57BL , Non-alcoholic Fatty Liver Disease/pathology , Oxidative Stress/drug effects , RAW 264.7 Cells , Xanthophylls/pharmacology , Xanthophylls/therapeutic use
11.
Int J Mol Sci ; 22(13)2021 Jul 04.
Article in English | MEDLINE | ID: mdl-34281260

ABSTRACT

Males have a higher risk for cardiovascular diseases (CVDs) than females. Ambient fine particulate matter (PM) exposure increases CVD risk with increased reactive oxygen species (ROS) production and oxidative stress. Endothelial progenitor cells (EPCs) are important to vascular structure and function and can contribute to the development of CVDs. The aims of the present study were to determine if sex differences exist in the effect of PM exposure on circulating EPCs in mice and, if so, whether oxidative stress plays a role. Male and female C57BL/6 mice (8-10 weeks old) were exposed to PM or a vehicle control for six weeks. ELISA analysis showed that PM exposure substantially increased the serum levels of IL-6 and IL-1ß in both males and females, but the concentrations were significantly higher in males. PM exposure only increased the serum levels of TNF-α in males. Flow cytometry analysis demonstrated that ROS production was significantly increased by PM treatment in males but not in females. Similarly, the level of circulating EPCs (CD34+/CD133+ and Sca-1+/Flk-1+) was significantly decreased by PM treatment in males but not in females. Antioxidants N-acetylcysteine (NAC) effectively prevented PM exposure-induced ROS and inflammatory cytokine production and restored circulating EPC levels in male mice. In sharp contrast, circulating EPC levels remained unchanged in female mice with PM exposure, an effect that was not altered by ovariectomy. In conclusion, PM exposure selectively decreased the circulating EPC population in male mice via increased oxidative stress without a significant impact on circulating EPCs in females independent of estrogen.


Subject(s)
Endothelial Progenitor Cells/drug effects , Endothelial Progenitor Cells/metabolism , Particulate Matter/toxicity , Acetylcysteine/pharmacology , Animals , Antioxidants/pharmacology , Apoptosis/drug effects , Cardiovascular Diseases/etiology , Cardiovascular Diseases/metabolism , Cytokines/blood , Endothelial Progenitor Cells/pathology , Estrogens/metabolism , Female , Inflammation Mediators/blood , Male , Mice , Mice, Inbred C57BL , Ovariectomy , Oxidative Stress/drug effects , Reactive Oxygen Species/metabolism , Sex Factors
12.
Am J Physiol Cell Physiol ; 319(1): C105-C115, 2020 07 01.
Article in English | MEDLINE | ID: mdl-32374674

ABSTRACT

Transforming growth factor-ß (TGF-ß)-induced fibroblast activation is a key pathological event during tissue fibrosis. Long noncoding RNA (lncRNA) is a class of versatile gene regulators participating in various cellular and molecular processes. However, the function of lncRNA in fibroblast activation is still poorly understood. In this study, we identified growth arrest-specific transcript 5 (GAS5) as a novel regulator for TGF-ß-induced fibroblast activation. GAS5 expression was downregulated in cultured fibroblasts by TGF-ß and in resident fibroblasts from bleomycin-treated skin tissues. Overexpression of GAS5 suppressed TGF-ß-induced fibroblast to myofibroblast differentiation. Mechanistically, GAS5 directly bound mothers against decapentaplegic homolog 3 (Smad3) and promoted Smad3 binding to Protein phosphatase 1A (PPM1A), a Smad3 dephosphatase, and thus accelerated Smad3 dephosphorylation in TGF-ß-treated fibroblasts. In addition, GAS5 inhibited fibroblast proliferation. Importantly, local delivery of GAS5 via adenoviral vector suppressed bleomycin-induced skin fibrosis in mice. Collectively, our data revealed that GAS5 suppresses fibroblast activation and fibrogenesis through inhibiting TGF-ß/Smad3 signaling, which provides a rationale for an lncRNA-based therapy to treat fibrotic diseases.


Subject(s)
Fibroblasts/metabolism , RNA, Long Noncoding/biosynthesis , Signal Transduction/physiology , Smad3 Protein/antagonists & inhibitors , Smad3 Protein/metabolism , Animals , Fibroblasts/pathology , Male , Mice , Mice, Inbred C57BL , NIH 3T3 Cells , RNA, Long Noncoding/genetics , Skin Diseases/genetics , Skin Diseases/pathology , Transforming Growth Factor beta/antagonists & inhibitors , Transforming Growth Factor beta/metabolism
13.
Gastroenterology ; 156(2): 510-524, 2019 01.
Article in English | MEDLINE | ID: mdl-30287171

ABSTRACT

Treatment options for patients with hepatocellular carcinoma are rapidly changing based on positive results from phase 3 trials of targeted and immune-based therapies. More agents designed to target specific pathways and immune checkpoints are in clinical development. Some agents have already been shown to improve outcomes of patients with hepatocellular carcinoma, as first- and second-line therapies, and are awaiting approval by the Food and Drug Administration or have been recently approved. We summarize the targeted and immune-based agents in trials of patients with advanced hepatocellular carcinoma and discuss the future of these strategies for liver cancer.


Subject(s)
Carcinoma, Hepatocellular/drug therapy , Immunotherapy , Liver Neoplasms/drug therapy , Molecular Targeted Therapy , Antineoplastic Agents/therapeutic use , Carcinoma, Hepatocellular/immunology , Carcinoma, Hepatocellular/pathology , Humans , Immunologic Factors/therapeutic use , Liver Neoplasms/immunology , Liver Neoplasms/pathology
14.
Sensors (Basel) ; 20(16)2020 Aug 05.
Article in English | MEDLINE | ID: mdl-32764226

ABSTRACT

Spatially location and working status of pollution sources are very important pieces of information for environment protection. Waste gas produced by fossil fuel consumption in the industry is mainly discharged to the atmosphere through a chimney. Therefore, detecting the distribution of chimneys and their working status is of great significance to urban environment monitoring and environmental governance. In this paper, we use an open access dataset BUAA-FFPP60 and the faster regions with convolutional neural network (Faster R-CNN) algorithm to train the preliminarily detection model. Then, the trained model is used to detect the chimneys in three high-resolution remote sensing images of Google Maps, which is located in Tangshan city. The results show that a large number of false positive targets are detected. For working chimney detection, the recall rate is 77.27%, but the precision is only 40.47%. Therefore, two spatial analysis methods, the digital terrain model (DTM) filtering, and main direction test are introduced to remove the false chimneys. The DTM is generated by ZiYuan-3 satellite images and then registered to the high-resolution image. We set an elevation threshold to filter the false positive targets. After DTM filtering, we use principle component analysis (PCA) to calculate the main direction of each target image slice, and then use the main direction to remove false positive targets further. The results show that by using the combination of DTM filtering and main direction test, more than 95% false chimneys can be removed and, therefore, the detection precision is significantly increased.

15.
Int J Mol Sci ; 21(5)2020 Mar 09.
Article in English | MEDLINE | ID: mdl-32182935

ABSTRACT

Although molecular mechanisms driving tumor progression have been extensively studied, the biological nature of the various populations of circulating tumor cells (CTCs) within the blood is still not well understood. Tumor cell fusion with immune cells is a longstanding hypothesis that has caught more attention in recent times. Specifically, fusion of tumor cells with macrophages might lead to the development of metastasis by acquiring features such as genetic and epigenetic heterogeneity, chemotherapeutic resistance, and immune tolerance. In addition to the traditional FDA-approved definition of a CTC (CD45-, EpCAM+, cytokeratins 8+, 18+ or 19+, with a DAPI+ nucleus), an additional circulating cell population has been identified as being potential fusions cells, characterized by distinct, large, polymorphonuclear cancer-associated cells with a dual epithelial and macrophage/myeloid phenotype. Artificial fusion of tumor cells with macrophages leads to migratory, invasive, and metastatic phenotypes. Further studies might investigate whether these have a potential impact on the immune response towards the cancer. In this review, the background, evidence, and potential relevance of tumor cell fusions with macrophages is discussed, along with the potential role of intercellular connections in their formation. Such fusion cells could be a key component in cancer metastasis, and therefore, evolve as a diagnostic and therapeutic target in cancer precision medicine.


Subject(s)
Biomarkers, Tumor/blood , Macrophages/pathology , Neoplasm Metastasis/pathology , Neoplasms/pathology , Animals , Humans , Neoplasms/blood , Neoplastic Cells, Circulating/pathology
16.
Gastroenterology ; 154(4): 1024-1036.e9, 2018 03.
Article in English | MEDLINE | ID: mdl-29408569

ABSTRACT

BACKGROUND & AIMS: Ceramide, a sphingolipid metabolite, affects T-cell signaling, induces apoptosis of cancer cells, and slows tumor growth in mice. However, it has not been used as a chemotherapeutic agent because of its cell impermeability and precipitation in aqueous solution. We developed a nanoliposome-loaded C6-ceremide (LipC6) to overcome this limitation and investigated its effects in mice with liver tumors. METHODS: Immune competent C57BL/6 mice received intraperitoneal injections of carbon tetrachloride and intra-splenic injections of oncogenic hepatocytes. As a result, tumors resembling human hepatocellular carcinomas developed in a fibrotic liver setting. After tumors formed, mice were given an injection of LipC6 or vehicle via tail vein every other day for 2 weeks. This was followed by administration, also via tail vein, of tumor antigen-specific (TAS) CD8+ T cells isolated from the spleens of line 416 mice, and subsequent immunization by intraperitoneal injection of tumor antigen-expressing B6/WT-19 cells. Tumor growth was monitored with magnetic resonance imaging. Tumor apoptosis, proliferation, and AKT expression were analyzed using immunohistochemistry and immunoblots. Cytokine production, phenotype, and function of TAS CD8+ T cells and tumor-associated macrophages (TAMs) were studied with flow cytometry, real-time polymerase chain reaction (PCR), and ELISA. Reactive oxygen species (ROS) in TAMs and bone marrow-derived macrophages, induced by colony stimulating factor 2 (GMCSF or CSF2) or colony stimulating factor 1 (MCSF or CSF1), were detected using a luminescent assay. RESULTS: Injection of LipC6 slowed tumor growth by reducing tumor cell proliferation and phosphorylation of AKT, and increasing tumor cell apoptosis, compared with vehicle. Tumors grew more slowly in mice given the combination of LipC6 injection and TAS CD8+ T cells followed by immunization compared with mice given vehicle, LipC6, the T cells, or immunization alone. LipC6 injection also reduced numbers of TAMs and their production of ROS. LipC6 induced TAMs to differentiate into an M1 phenotype, which reduced immune suppression and increased activity of CD8+ T cells. These results were validated by experiments with bone marrow-derived macrophages induced by GMCSF or MCSF. CONCLUSIONS: In mice with liver tumors, injection of LipC6 reduces the number of TAMs and the ability of TAMs to suppress the anti-tumor immune response. LipC6 also increases the anti-tumor effects of TAS CD8+ T cells. LipC6 might therefore increase the efficacy of immune therapy in patients with hepatocellular carcinoma.


Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Hepatocellular/drug therapy , Ceramides/pharmacology , Liver Neoplasms/drug therapy , Tumor Burden/drug effects , Animals , Antigens, Polyomavirus Transforming/genetics , Apoptosis/drug effects , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/transplantation , Carcinoma, Hepatocellular/immunology , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Line, Transformed , Cell Proliferation/drug effects , Cytokines/metabolism , Immunotherapy, Adoptive/methods , Liposomes , Liver Neoplasms/immunology , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Macrophages/drug effects , Macrophages/immunology , Macrophages/metabolism , Magnetic Resonance Imaging , Male , Mice, Inbred C57BL , Mice, Transgenic , Nanoparticles , Promoter Regions, Genetic , Proteins/genetics , Proto-Oncogene Proteins c-akt/metabolism , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Time Factors , Tumor Escape/drug effects , Tumor Microenvironment
17.
Anal Chem ; 91(5): 3467-3474, 2019 03 05.
Article in English | MEDLINE | ID: mdl-30693764

ABSTRACT

Strongly red luminescent and water-soluble probes are very important for studying biological events and processes. Fluorescent nanoparticles (NPs) built from the aggregation-induced emission luminogen (AIEgen) and amphipathic polymeric matrixes have been considered as promising candidates for bioimaging. However, AIE NPs with long-wavelength absorption suitable for in vivo application are still scarce. In this work, three AIE-active red-emissive BODIPY derivatives with long-wavelength absorption were rationally designed and synthesized. Then three NPs based on these AIEgens exhibit bright red photoluminescence with high fluorescence quantum yield in aqueous media. These NPs uniformly dispersed in water and showed excellent stability and good biocompatibility. They can be readily internalized by HeLa cells, and the staining process is performed by simply shaking the culture with cells for just a few seconds at room temperature, which indicates an ultrafast and easy-to-operate staining protocol. More importantly, long-term tracing in living cells and mouse over 15 days is successfully achieved. The strong fluorescence signals, ultrafast staining procedure, and long-term tracing abilities indicate that these AIE NPs hold great potential for monitoring biological processes.


Subject(s)
Fluorescent Dyes/chemistry , Nanoparticles/chemistry , Optical Imaging , Uterine Cervical Neoplasms/diagnostic imaging , Animals , Female , Fluorescence , Fluorescent Dyes/chemical synthesis , HeLa Cells , Humans , Male , Mice , Mice, Inbred BALB C , Molecular Structure , Tumor Cells, Cultured
18.
J Hepatol ; 66(1): 75-85, 2017 01.
Article in English | MEDLINE | ID: mdl-27520877

ABSTRACT

BACKGROUND & AIMS: We have established a clinically relevant animal model of hepatocellular cancer (HCC) in immune competent mice to elucidate the complex dialog between host immunity and tumors during HCC initiation and progression. Mechanistic findings have been leveraged to develop a clinically feasible anti-tumor chemoimmunotherapeutic strategy. METHODS: Intraperitoneal injection of carbon tetrachloride and intrasplenic inoculation of oncogenic hepatocytes were combined to induce progressive HCCs in fibrotic livers of immunocompetent mice. Immunization and adoptive cell transfer (ACT) were used to dissect the tumor antigen-specific immune response. The ability of the tyrosine kinase inhibitor sunitinib to enhance immunotherapy in the setting of HCC was evaluated. RESULTS: This new mouse model mimics human HCC and reflects its typical features. Tumor-antigen-specific CD8+ T cells maintained a naïve phenotype and remained responsive during early-stage tumor progression. Late tumor progression produced circulating tumor cells, tumor migration into draining lymph nodes, and profound exhaustion of tumor-antigen-specific CD8+ T cells associated with accumulation of programmed cell death protein 1 (PD-1)hi CD8+ T cells and regulatory T cells (Tregs). Sunitinib-mediated tumoricidal effect and Treg suppression synergized with antibody-mediated blockade of PD-1 to powerfully suppress tumor growth and activate anti-tumor immunity. CONCLUSION: Treg accumulation and upregulation of PD-1 provide two independent mechanisms to induce profound immune tolerance in HCC. Chemoimmunotherapy using Food and Drug Administration-approved sunitinib with anti-PD-1 antibodies achieved significant tumor control, supporting translation of this approach for the treatment of HCC patients. LAY SUMMARY: In the current study, we have established a clinically relevant mouse model which mimics human liver cancer. Using this unique model, we studied the response of the immune system to this aggressive cancer. Findings from this trial have led to the development of an innovative and clinically feasible chemoimmunotherapeutic strategy.


Subject(s)
Carcinoma, Hepatocellular , Immunotherapy/methods , Indoles/pharmacology , Liver Neoplasms , Pyrroles/pharmacology , Adoptive Transfer , Animals , CD8-Positive T-Lymphocytes/immunology , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/immunology , Carcinoma, Hepatocellular/pathology , Cytotoxicity, Immunologic/physiology , Disease Models, Animal , Enzyme Inhibitors/pharmacology , Histocompatibility Antigens Class II/immunology , Immune Tolerance , Liver Neoplasms/drug therapy , Liver Neoplasms/immunology , Liver Neoplasms/pathology , Mice , Neoplasm Staging , Programmed Cell Death 1 Receptor/metabolism , Sunitinib , T-Lymphocytes, Regulatory/immunology
19.
Chemistry ; 23(49): 11761-11766, 2017 Sep 04.
Article in English | MEDLINE | ID: mdl-28737275

ABSTRACT

The mechanism of thermally activated delayed fluorescence (TADF) in molecules in aggregated or condensed solid states has been rarely studied and is not well understood. Nevertheless, many applications of TADF emitters are strongly affected by their luminescence properties in the aggregated state. In this study, two new isomeric tetradentate CuI complexes which simultaneously show aggregation induced emission (AIE) and TADF characteristics are reported for the first time. We provide direct evidence that effectively restricting the vibrations of individual molecules is a key requisite for TADF in these two CuI complexes through in-depth photophysical measurements combined with kinetic methods, single crystal analysis and theoretical calculations. These findings should stimulate new molecular engineering endeavours in the design of AIE-TADF active materials with highly emissive aggregated states.

20.
Anim Biotechnol ; 25(4): 234-49, 2014.
Article in English | MEDLINE | ID: mdl-24813218

ABSTRACT

In recent years, the population size of Taiwan yellow cattle has drastically declined, even become endangered. A preservation project, Taiwan Yellow Cattle Genetic Preservation Project (TYCGPP), was carried out at the Livestock Research Institute (LRI) Hengchun branch (1988-present). An analysis of intra- and inter- population variability was performed to be the first step to preserve this precious genetic resource. In this work, a total number of 140 individuals selected from the five Taiwan yellow cattle populations were analyzed using 12 microsatellite markers (loci). These markers determined the level of genetic variation within and among populations as well as the phylogenetic structure. The total number of alleles detected (122, 10.28 per locus) and the expected heterozygosity (0.712) indicated that these five populations had a high level of genetic variability. Bayesian cluster analysis showed that the most likely number of groups was 2 (K = 2). Genetic differentiation among clusters was moderate (F ST = 0.095). The result of AMOVA showed that yellow cattle in Taiwan had maintained a high level of within-population genetic differentiation (91%), the remainder being accounted for by differentiation among subpopulations (4%), and by differentiation among regions (5%). The results of STRUCTURE and principal component analysis (PCA) revealed two divergent clusters. The individual unrooted phylogenetic tree showed that some Kinmen yellow cattle in the Hengchun facility (KMHC individuals) were overlapped with Taiwan yellow cattle (TW) and Taiwan yellow cattle Hengchun (HC) populations. Also, they were overlapped with Kinmen × Taiwan (KT) and Kinmen yellow cattle (KM) populations. It is possible that KMHC kept similar phenotypic characteristics and analogous genotypes between TW and KM. A significant inbreeding coefficient (F IS = 0.185; P < 0.01) was detected, suggesting a medium level of inbreeding for yellow cattle in Taiwan. The hypothesis that yellow cattle in Taiwan were derived from two different clusters was also supported by the phylogenetic tree constructed by the UPGMA, indicating that the yellow cattle in Taiwan and in Kinmen should be treated as two different management units. This result will be applied to maintain a good level of genetic variability and rusticity (stress-resistance) and to avoid further inbreeding for yellow cattle population in Taiwan.


Subject(s)
Cattle/genetics , Genetic Variation/genetics , Microsatellite Repeats/genetics , Animals , Breeding , Genetics, Population , Taiwan
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