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1.
Cell ; 158(1): 69-83, 2014 Jul 03.
Article in English | MEDLINE | ID: mdl-24995979

ABSTRACT

Brown fat can reduce obesity through the dissipation of calories as heat. Control of thermogenic gene expression occurs via the induction of various coactivators, most notably PGC-1α. In contrast, the transcription factor partner(s) of these cofactors are poorly described. Here, we identify interferon regulatory factor 4 (IRF4) as a dominant transcriptional effector of thermogenesis. IRF4 is induced by cold and cAMP in adipocytes and is sufficient to promote increased thermogenic gene expression, energy expenditure, and cold tolerance. Conversely, knockout of IRF4 in UCP1(+) cells causes reduced thermogenic gene expression and energy expenditure, obesity, and cold intolerance. IRF4 also induces the expression of PGC-1α and PRDM16 and interacts with PGC-1α, driving Ucp1 expression. Finally, cold, ß-agonists, or forced expression of PGC-1α are unable to cause thermogenic gene expression in the absence of IRF4. These studies establish IRF4 as a transcriptional driver of a program of thermogenic gene expression and energy expenditure.


Subject(s)
Adipose Tissue, Brown/metabolism , Interferon Regulatory Factors/metabolism , Thermogenesis , Transcription Factors/metabolism , Transcriptional Activation , Adipocytes/metabolism , Adipose Tissue, Brown/cytology , Adrenergic beta-3 Receptor Agonists/pharmacology , Animals , Cold Temperature , Cyclic AMP/metabolism , Energy Metabolism , Humans , Ion Channels/genetics , Mice , Mitochondria/metabolism , Mitochondrial Proteins/genetics , Obesity/metabolism , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha , Thinness/metabolism , Transcriptional Activation/drug effects , Uncoupling Protein 1
2.
Phys Rev Lett ; 131(7): 073401, 2023 Aug 18.
Article in English | MEDLINE | ID: mdl-37656862

ABSTRACT

Ultracold atoms in optical lattices form a competitive candidate for quantum computation owing to the excellent coherence properties, the highly parallel operations over spins, and the ultralow entropy achieved in qubit arrays. For this, a massive number of parallel entangled atom pairs have been realized in superlattices. However, the more formidable challenge is to scale up and detect multipartite entanglement, the basic resource for quantum computation, due to the lack of manipulations over local atomic spins in retroreflected bichromatic superlattices. In this Letter, we realize the functional building blocks in quantum-gate-based architecture by developing a cross-angle spin-dependent optical superlattice for implementing layers of quantum gates over moderately separated atoms incorporated with a quantum gas microscope for single-atom manipulation and detection. Bell states with a fidelity of 95.6(5)% and a lifetime of 2.20±0.13 s are prepared in parallel, and then connected to multipartite entangled states of one-dimensional ten-atom chains and two-dimensional plaquettes of 2×4 atoms. The multipartite entanglement is further verified with full bipartite nonseparability criteria. This offers a new platform toward scalable quantum computation and simulation.

3.
Small ; 18(27): e2201298, 2022 07.
Article in English | MEDLINE | ID: mdl-35652504

ABSTRACT

Cancer immunotherapy has great potential in tumor eradication and metastasis suppression. However, systemic administration of immune adjuvants and inadequate specificity in cancer treatment, lead to restricted therapeutic benefits and potential immune-related side effects in clinical settings. In this report, the synthesis of various lengths of heptamethine cyanine small molecules to act as multifunctional photosensitizers (PS) for tumor-specific accumulation, near-infrared (NIR) fluorescent imaging, and photodynamic/photothermal/immunotherapy is optimized. In particular, it is demonstrated that C8, which contains eight carbons on two N-alkyl side chains, efficiently self-assembles with albumin to form nanosized dye-albumin complexes. This feature facilitates C8 in vivo self-assembly to remarkably improve its water-solubility, NIR fluorescent emission, long-term blood circulation, as well as tumor-specific accumulation. More importantly, C8 not only exhibits a superior phototherapeutic effect on primary tumors, but also elicits secretion of damage associated molecular patterns, cytokine secretion, dendritic cell maturation, and cytotoxic T lymphocytes activation, ultimately triggering a sufficient antitumor immune response to suppress growths of distant and metastatic tumors. Hence, this multifunctional small molecular PS is characterized with excellent tumor-preferential accumulation, imaging-guided laser irradiation, and phototherapy-induced in situ antitumor immune response, providing a prospective future of its use in tumor-targeting immunotherapy.


Subject(s)
Nanoparticles , Neoplasms , Albumins , Cell Line, Tumor , Coloring Agents , Humans , Immunotherapy , Nanoparticles/chemistry , Neoplasms/diagnostic imaging , Neoplasms/therapy , Photosensitizing Agents/therapeutic use , Phototherapy/methods , Prospective Studies
4.
Opt Express ; 30(15): 26856-26864, 2022 Jul 18.
Article in English | MEDLINE | ID: mdl-36236869

ABSTRACT

Complex-amplitude modulation of light fields with a digital micromirror device (DMD) has been widely used in holographic image projection. DMD is a binary-amplitude modulator, and its use for complex field modulation in a 4f configuration requires low-pass filtering. However, the reconstructed fields suffer from low resolution due to the limited bandwidth for the existing methods such as the Lee and superpixel methods. Here, we report a direct binary search (DBS) method to design high-resolution complex-amplitude holograms. The method is able to increase the spatial bandwidth up to twice that of the superpixel method. Numerical simulations and experiments are presented to demonstrate the method, which show that the errors are reduced by about 60% and 40% respectively for the test fields compared to the superpixel method. Furthermore, the measured efficiency of laser light can be improved by a maximum of 60%.

5.
Proc Natl Acad Sci U S A ; 112(11): E1307-16, 2015 Mar 17.
Article in English | MEDLINE | ID: mdl-25737553

ABSTRACT

The synthesis and processing of mRNA, from transcription to translation initiation, often requires splicing of intragenic material. The final mRNA composition varies based on proteins that modulate splice site selection. EWS-FLI1 is an Ewing sarcoma (ES) oncoprotein with an interactome that we demonstrate to have multiple partners in spliceosomal complexes. We evaluate the effect of EWS-FLI1 on posttranscriptional gene regulation using both exon array and RNA-seq. Genes that potentially regulate oncogenesis, including CLK1, CASP3, PPFIBP1, and TERT, validate as alternatively spliced by EWS-FLI1. In a CLIP-seq experiment, we find that EWS-FLI1 RNA-binding motifs most frequently occur adjacent to intron-exon boundaries. EWS-FLI1 also alters splicing by directly binding to known splicing factors including DDX5, hnRNP K, and PRPF6. Reduction of EWS-FLI1 produces an isoform of γ-TERT that has increased telomerase activity compared with wild-type (WT) TERT. The small molecule YK-4-279 is an inhibitor of EWS-FLI1 oncogenic function that disrupts specific protein interactions, including helicases DDX5 and RNA helicase A (RHA) that alters RNA-splicing ratios. As such, YK-4-279 validates the splicing mechanism of EWS-FLI1, showing alternatively spliced gene patterns that significantly overlap with EWS-FLI1 reduction and WT human mesenchymal stem cells (hMSC). Exon array analysis of 75 ES patient samples shows similar isoform expression patterns to cell line models expressing EWS-FLI1, supporting the clinical relevance of our findings. These experiments establish systemic alternative splicing as an oncogenic process modulated by EWS-FLI1. EWS-FLI1 modulation of mRNA splicing may provide insight into the contribution of splicing toward oncogenesis, and, reciprocally, EWS-FLI1 interactions with splicing proteins may inform the splicing code.


Subject(s)
Alternative Splicing/genetics , Oncogene Proteins, Fusion/metabolism , Proto-Oncogene Protein c-fli-1/metabolism , RNA-Binding Protein EWS/metabolism , Signal Transduction/genetics , Alternative Splicing/drug effects , Base Sequence , Cell Line, Tumor , Exons/genetics , Humans , Indoles , Introns/genetics , Oncogene Proteins, Fusion/genetics , Protein Binding/drug effects , Protein Isoforms/metabolism , Proto-Oncogene Protein c-fli-1/genetics , RNA Processing, Post-Transcriptional/drug effects , RNA Processing, Post-Transcriptional/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA-Binding Protein EWS/genetics , Sarcoma, Ewing/genetics , Sarcoma, Ewing/pathology , Signal Transduction/drug effects , Spliceosomes/drug effects , Spliceosomes/metabolism , Telomerase/metabolism
6.
J Pineal Res ; 63(1)2017 Aug.
Article in English | MEDLINE | ID: mdl-28247536

ABSTRACT

Cellular senescence is an important tumor-suppressive mechanism. However, acquisition of a senescence-associated secretory phenotype (SASP) in senescent cells has deleterious effects on the tissue microenvironment and, paradoxically, promotes tumor progression. In a drug screen, we identified melatonin as a novel SASP suppressor in human cells. Strikingly, melatonin blunts global SASP gene expression upon oncogene-induced senescence (OIS). Moreover, poly(ADP-ribose) polymerase-1 (PARP-1), a sensor of DNA damage, was identified as a new melatonin-dependent regulator of SASP gene induction upon OIS. Here, we report two different but potentially coherent epigenetic strategies for melatonin regulation of SASP. The interaction between the telomeric repeat-containing RNA (TERRA) and PARP-1 stimulates the SASP, which was attenuated by 67.9% (illustrated by the case of IL8) by treatment with melatonin. Through binding to macroH2A1.1, PARP-1 recruits CREB-binding protein (CBP) to mediate acetylation of H2BK120, which positively regulates the expression of target SASP genes, and this process is interrupted by melatonin. Consequently, the findings provide novel insight into melatonin's epigenetic role via modulating PARP-1 in suppression of SASP gene expression in OIS-induced senescent cells. Our studies identify melatonin as a novel anti-SASP molecule, define PARP-1 as a new target by which melatonin regulates SASP, and establish a new epigenetic paradigm for a pharmacological mechanism by which melatonin interrupts PARP-1 interaction with the telomeric long noncoding RNA(lncRNA) or chromatin.


Subject(s)
Cellular Senescence/drug effects , Fibroblasts/drug effects , Melatonin/pharmacology , Poly (ADP-Ribose) Polymerase-1/metabolism , Cell Line , Cells, Cultured , Cellular Senescence/genetics , Fibroblasts/metabolism , Humans , Lung/cytology , Poly (ADP-Ribose) Polymerase-1/genetics
7.
J Surg Res ; 193(1): 279-88, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25128389

ABSTRACT

BACKGROUND: Metastatic initiation has many phenotypic similarities to epithelial-to-mesenchymal transition, including loss of cell-cell adhesion, increased invasiveness, and increased cell mobility. We have previously demonstrated that drug resistance is associated with a metastatic phenotype in neuroblastoma (NB). The purpose of this project was to determine if the development of doxorubicin resistance is associated with characteristics of mesenchymal change in human NB cells. MATERIALS AND METHODS: Total RNA was isolated from wild type (WT) and doxorubicin-resistant (DoxR) human NB cell lines (SK-N-SH and SK-N-BE(2)C) and analyzed using the Illumina Human HT-12 version 4 Expression BeadChip. Differentially expressed genes (DEGs) were identified. Volcano plots and heat maps were generated. Genes of interest with a fold change in expression >1.5 and an adjusted P < 0.1 were analyzed. Immunofluorescence (IF) and Western blot analysis confirmed microarray results of interest. Matrigel invasion assay and migration wounding assays were performed. RESULTS: Volcano plots and heat maps visually demonstrated a similar pattern of DEGs in the SK-N-SH and SK-N-BE(2)C DoxR cell lines relative to their parental WT lines. Venn diagramming revealed 1594 DEGs common to both DoxR cell lines relative to their parental cell lines. Network analysis pointed to several significantly upregulated epithelial-to-mesenchymal transition pathways, through TGF-beta pathways via RhoA, PI3K, and ILK and via SMADs, as well as via notch signaling pathways. DoxR cell lines displayed a more invasive phenotype than respective WT cell lines. CONCLUSIONS: Human SK-N-SH and SK-N-BE(2)C NB cells display characteristics of mesenchymal change via multiple pathways in the transition to a drug-resistant state.


Subject(s)
Doxorubicin/pharmacology , Drug Resistance, Neoplasm/genetics , Epithelial-Mesenchymal Transition/drug effects , Epithelial-Mesenchymal Transition/genetics , Neuroblastoma , Antibiotics, Antineoplastic/pharmacology , Cell Adhesion , Cell Line, Tumor , Cell Movement , Female , Gene Expression Regulation, Neoplastic , Genome-Wide Association Study , Humans , Male , Neoplasm Invasiveness , Neuroblastoma/drug therapy , Neuroblastoma/genetics , Neuroblastoma/secondary , Phenotype , Signal Transduction/drug effects , Signal Transduction/physiology
8.
Biochim Biophys Acta ; 1833(12): 2996-3005, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23954443

ABSTRACT

Phosphate-activated mitochondrial glutaminase (GLS2) is suggested to be linked with elevated glutamine metabolism. It plays an important role in catalyzing the hydrolysis of glutamine to glutamate. The present study was to investigate the potent effect of GLS2 on radioresistance of cervical carcinoma. GLS2 was examined in 144 cases of human cervical cancer specimens (58 radioresistant specimens, 86 radiosensitive specimens) and 15 adjacent normal cervical specimens with immunohistochemistry. HeLa cells were treated with a cumulative dose of 50Gy X-rays, over 6months, yielding the resistant sub-line HeLaR. The expressions of GLS2 were measured by Western blot. Radioresistance was tested by colony survival assay. Apoptosis was determined by flow cytometry. The levels of glutathione (GSH), reactive oxygen species (ROS), NAD(+)/NADH ratio and NADP(+)/NADPH ratio were detected by quantization assay kit. Xenografts were used to confirm the effect of GLS2 on radioresistance in vivo. The expressions of GLS2 were significantly enhanced in tumor tissues of radioresistant patients compared with that in radiosensitive patients. In vitro, the radioresistant cell line HeLaR exhibited significantly increased GLS2 levels than its parental cell line HeLa. GLS2 silenced radioresistant cell HeLaR shows substantially enhanced radiosensitivity with lower colony survival and higher apoptosis in response to radiation. In vivo, xenografts with GLS2 silenced HeLaR were more sensitive to radiation. At the molecular level, knock-down of GLS2 increased the intracellular ROS levels of HeLaR exposed to irradiation by decreasing the productions of antioxidant GSH, NADH and NADPH. GLS2 may have an important role in radioresistance in cervical cancer patients.


Subject(s)
Gene Knockdown Techniques , Glutaminase/metabolism , Glutathione/metabolism , NAD/metabolism , Radiation, Ionizing , Uterine Cervical Neoplasms/radiotherapy , Animals , Antioxidants/metabolism , Cell Line, Tumor , Female , HEK293 Cells , Humans , Immunohistochemistry , Intracellular Space/metabolism , Intracellular Space/radiation effects , Mice , Mice, Nude , Middle Aged , Radiation Tolerance/radiation effects , Reactive Oxygen Species/metabolism , Uterine Cervical Neoplasms/enzymology , Uterine Cervical Neoplasms/pathology , Xenograft Model Antitumor Assays
9.
J Cancer Res Ther ; 19(4): 957-963, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37675723

ABSTRACT

Purpose: To investigate the effects of iodine-125 seed brachytherapy (ISB) on the overall survival (OS) of patients with heterochronous pulmonary metastasis (HPM) secondary to hepatocellular carcinoma (HCC). Materials and Methods: The clinical and imaging data of 123 patients with HPM secondary to HCC treated at a single center from July 2012 to July 2020 were analyzed retrospectively. The patients were divided into ISB and non-ISB groups based on ISB treatment. Propensity score matching yielded 46 pairs of patients. A total of 191 lesions were treated, and the data were evaluated for 6 months after ISB. The OS rates of the two groups were compared using the Kaplan-Meier method. Independent prognostic factors were determined using a Cox proportional hazards regression model. Results: The percentages of lung lesions in complete remission, partial remission, disease stable, and disease progression stages were 49.2%, 32.8%, 9.6%, and 8.4%, respectively. The disease control rate was 91.6%. The median follow-up time from the initial diagnosis was 47 months and 33 months for the ISB and non-ISB groups, respectively. Patients in the ISB group had a longer OS than those in the non-ISB group (1-year: 95.7% vs. 80.3%; 3-year: 62.9% vs. 45.7%; 5-year: 37% vs. 20.9%; P < 0.05). Multivariate analysis demonstrated that ISB treatment, tumor differentiation, vascular invasion, and Child - Pugh score were independent prognostic factors for survival. Conclusion: ISB improves local control and OS rates of HPM secondary to HCC; thus, it is an effective and feasible option for patients with HPM secondary to HCC.


Subject(s)
Brachytherapy , Carcinoma, Hepatocellular , Liver Neoplasms , Lung Neoplasms , Humans , Carcinoma, Hepatocellular/radiotherapy , Liver Neoplasms/radiotherapy , Lung Neoplasms/radiotherapy , Propensity Score , Retrospective Studies
10.
Adv Sci (Weinh) ; 10(10): e2206779, 2023 04.
Article in English | MEDLINE | ID: mdl-36739599

ABSTRACT

Due to radiation resistance and the immunosuppressive microenvironment of metastatic osteosarcoma, novel radiosensitizers that can sensitize radiotherapy (RT) and antitumor immunity synchronously urgently needed. Here, the authors developed a nanoscale metal-organic framework (MOF, named TZM) by co-doping high-atomic elements Ta and Zr as metal nodes and porphyrinic molecules (tetrakis(4-carboxyphenyl)porphyrin (TCPP)) as a photosensitizing ligand. Given the 3D arrays of ultra-small heavy metals, porous TZM serves as an efficient attenuator absorbing X-ray energy and sensitizing hydroxyl radical generation for RT. Ta-Zr co-doping narrowed the highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) energy gap and exhibited close energy levels between the singlet and triplet photoexcited states, facilitating TZM transfer energy to the photosensitizer TCPP to sensitize singlet oxygen (1 O2 ) generation for radiodynamic therapy (RDT). The sensitized RT-RDT effects of TZM elicit a robust antitumor immune response by inducing immunogenic cell death, promoting dendritic cell maturation, and upregulating programmed cell death protein 1 (PD-L1) expression via the cGAS-STING pathway. Furthermore, a combination of TZM, X-ray, and anti-PD-L1 treatments amplify antitumor immunotherapy and efficiently arrest osteosarcoma growth and metastasis. These results indicate that TZM is a promising radiosensitizer for the synergistic RT and immunotherapy of metastatic osteosarcoma.


Subject(s)
Metal-Organic Frameworks , Osteosarcoma , Humans , Zirconium , Tantalum , Immunotherapy/methods , Osteosarcoma/radiotherapy , Tumor Microenvironment
11.
Adv Healthc Mater ; 12(22): e2300220, 2023 09.
Article in English | MEDLINE | ID: mdl-37204240

ABSTRACT

Ferroptosis is a new type of iron-dependent programmed cell death characterized by glutathione (GSH) depletion, selenoprotein glutathione peroxidase 4 (GPX4) inactivation, and lipid peroxides accumulation. Mitochondria, as the main source of intracellular energy supply and reactive oxygen species (ROS) generation, play a central role in oxidative phosphorylation and redox homeostasis. Therefore, targeting cancer-cell mitochondria and attacking redox homeostasis is expected to induce robust ferroptosis-mediated anticancer effects. In this work, a theranostic ferroptosis inducer (IR780-SPhF), which can simultaneously achieve the imaging and therapy of triple-negative breast cancer (TNBC) by targeting mitochondria is presented. It is developed from a mitochondria-targeting small molecule (IR780) with cancer-preferential accumulation, enabling it to react with GSH by nucleophilic substitution, resulting in mitochondrial GSH depletion and redox imbalance. More interestingly, IR780-SPhF exhibits GSH-responsive near-infrared fluorescence emission and photoacoustic imaging characteristics, further facilitating diagnosis and treatment with real-time monitoring of TNBC with a highly elevated GSH level. Both in vitro and in vivo results demonstrate that IR780-SPhF exhibits potent anticancer effect, which is significantly stronger than cyclophosphamide, a classic drug commonly recommended for TNBC patients in clinic. Hence, the reported mitochondria-targeted ferroptosis inducer may represent a promising candidate and a prospective strategy for efficient cancer treatment.


Subject(s)
Ferroptosis , Triple Negative Breast Neoplasms , Humans , Triple Negative Breast Neoplasms/diagnostic imaging , Triple Negative Breast Neoplasms/drug therapy , Precision Medicine , Glutathione/metabolism , Reactive Oxygen Species/metabolism , Mitochondria/metabolism
12.
Front Oncol ; 13: 1175279, 2023.
Article in English | MEDLINE | ID: mdl-37274229

ABSTRACT

Primary pulmonary hyalinizing clear cell carcinoma (HCCC) is a rare salivary gland-type tumor newly recognized in recent years, with approximately 21 cases reported to date in the English literature, which constitutes a challenge in pathology diagnosis, particularly in small biopsy specimens. Here, we present a case of pulmonary HCCC diagnosed by computed tomography-guided percutaneous lung biopsy in a 70-year-old man's right lower lung. Although the morphology and immunophenotype of the tumor suggested the diagnosis of mucoepidermoid carcinoma, fluorescence in situ hybridization failed to reveal the rearrangement of MAML2 gene, which is characteristic of mucoepidermoid carcinoma. Instead, further molecular genetic testing showed that the tumor harbored a rare EWSR1::CREM fusion combined with a previously unreported IRF2::NTRK3 fusion. Pulmonary HCCC is commonly regarded as a low-grade malignant tumor with an indolent course, but this case has a different biological behavior, presenting extensive dissemination and metastases at the time of diagnosis, which expands our understanding of the prognosis of this tumor. The patient has had five cycles of combination chemotherapy and has been alive with the tumor for eight months.

13.
Cancer ; 118(7): 1884-93, 2012 Apr 01.
Article in English | MEDLINE | ID: mdl-22009660

ABSTRACT

BACKGROUND: Telomerase is commonly recognized as an effective anticancer target. The human telomerase reverse transcriptase (hTERT), the rate-limiting component of telomerase, is expressed in most malignant tumors, but it is not found in most normal somatic cells. Here, we report a real-time and noninvasive method to monitor tumor response to a lentivirus-based hTERT-conditional suicidal gene therapy. METHODS: In this study, we constructed a lentivirus system in which an optimized hTERT promoter was used to drive the expression of the cytosine deaminase (CD) gene, one of the suicide genes, and a green fluorescent protein (GFP) reporter gene (pLenti-CD/GFP). The lentivirus was used to infect telomerase-positive or telomerase-negative cell lines. In vitro and in vivo experiments were conducted to analyze the dynamic processes of exogenous gene expression noninvasively in cell culture and living animals in real time via optical imaging. RESULTS: The lentivirus was able to express the CD gene and GFP in telomerase-positive tumor cells and significantly decrease cell proliferation after the use of prodrug 5-flucytosine. However, it could not express GFP and CD in telomerase-negative cell lines, nor could it induce any suicidal effect in those cells. The in vivo study showed that telomerase-positive tumors can be visualized after intratumor injection of the lentivirus in tumor-bearing nude mice via an optical imaging system. Significant tumor growth suppression was observed in telomerase-positive tumors. CONCLUSIONS: Collectively, this technology provides a valuable, noninvasive method to evaluate the real-time therapeutic response of tumors in vivo.


Subject(s)
Computer Systems , Cytosine Deaminase/metabolism , Drug Monitoring/methods , Genetic Therapy/methods , Neoplasms/therapy , Telomerase/genetics , Animals , Cell Line, Tumor , Cytosine Deaminase/genetics , Flucytosine , Genes, Reporter , Genes, Transgenic, Suicide , Green Fluorescent Proteins/genetics , Humans , Lentivirus/genetics , Mice , Mice, Nude , Neoplasms/genetics , Promoter Regions, Genetic , Treatment Outcome , Xenograft Model Antitumor Assays
14.
J Hepatol ; 56(6): 1351-5, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22322235

ABSTRACT

BACKGROUND & AIMS: Gestational alloimmune liver disease is the main cause of the neonatal hemochromatosis phenotype, wherein severe neonatal liver disease is associated with iron overload and extrahepatic tissue siderosis. How fetal liver disease produces extrahepatic siderosis is not known. We hypothesized that fetal liver injury causes deficient hepcidin production and poor regulation of placental iron flux. Under the resulting conditions of iron overload, the tissue pattern of extrahepatic siderosis is determined by the normal expression of proteins involved in the import of non-transferrin-bound iron and the export of cellular iron. METHODS: Liver and extrahepatic tissues from infants with gestational alloimmune liver disease were examined and compared to normal age-appropriate tissues. RESULTS: Serum iron indices indicate iron overload and excess non-transferrin bound iron in gestational alloimmune liver disease. The diseased liver showed significantly reduced hepcidin, hemojuvulin, and transferrin gene expression compared to the normal fetal and neonatal liver. Those extrahepatic tissues that are typically involved in pathological siderosis in neonatal hemochromatosis, whether from normal or diseased newborns, consistently expressed solute carrier family 39 (zinc transporter), member 14 (ZIP14) for non-transferrin-bound iron uptake and expressed little ferroportin for iron export. CONCLUSIONS: Excess non-transferrin-bound iron in gestational alloimmune liver disease may result from fetal liver injury that causes reduced synthesis of key iron regulatory and transport proteins. Whereas, the pattern of extrahepatic siderosis appears to be determined by the normal capacity of various tissues to import non-transferrin-bound iron and not export cellular iron.


Subject(s)
Hemochromatosis/etiology , Isoantigens/immunology , Liver Diseases/complications , Pregnancy Complications , Siderosis/etiology , Antimicrobial Cationic Peptides/genetics , Female , GPI-Linked Proteins/genetics , Hemochromatosis Protein , Hepcidins , Humans , Infant, Newborn , Iron/metabolism , Pregnancy , Thromboplastin/genetics
15.
Am J Pathol ; 179(2): 703-13, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21801867

ABSTRACT

Fatty acyl-coenzyme A oxidase 1 (ACOX1) knockout (ACOX1(-/-)) mice manifest hepatic metabolic derangements that lead to the development of steatohepatitis, hepatocellular regeneration, spontaneous peroxisome proliferation, and hepatocellular carcinomas. Deficiency of ACOX1 results in unmetabolized substrates of this enzyme that function as biological ligands for peroxisome proliferator-activated receptor-α (PPARα) in liver. Here we demonstrate that sustained activation of PPARα in ACOX1(-/-) mouse liver by these ACOX1 substrates results in endoplasmic reticulum (ER) stress. Overexpression of transcriptional regulator p8 and its ER stress-related effectors such as the pseudokinase tribbles homolog 3, activating transcription factor 4, and transcription factor CCAAT/-enhancer-binding protein homologous protein as well as phosphorylation of eukaryotic translation initiation factor 2α, indicate the induction of unfolded protein response signaling in the ACOX1(-/-) mouse liver. We also show here that, in the liver, p8 is a target for all three PPAR isoforms (-α, -ß, and -γ), which interact with peroxisome proliferator response elements in p8 promoter. Sustained activation of p8 and unfolded protein response-associated ER stress in ACOX1(-/-) mouse liver contributes to hepatocyte apoptosis and liver cell proliferation culminating in the development of hepatocarcinogenesis. We also demonstrate that human ACOX1 transgene is functional in ACOX1(-/-) mice and effectively prevents metabolic dysfunctions that lead to ER stress and carcinogenic effects. Taken together, our data indicate that progressive PPARα- and p8-mediated ER stress contribute to the hepatocarcinogenesis in ACOX1(-/-) mice.


Subject(s)
Acyl-CoA Oxidase/deficiency , DNA-Binding Proteins/genetics , Endoplasmic Reticulum/metabolism , Liver Neoplasms/pathology , Neoplasm Proteins/genetics , PPAR alpha/genetics , Acyl-CoA Oxidase/genetics , Animals , DNA Primers/genetics , Gene Expression Regulation , Genotype , Hepatocytes/cytology , Humans , Liver/metabolism , Liver Neoplasms/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Models, Biological , Transgenes
16.
Materials (Basel) ; 15(9)2022 May 09.
Article in English | MEDLINE | ID: mdl-35591721

ABSTRACT

The experiment of rock-like material plays an important role in the simulation of engineering fractured rock mass. To further understand the influence of raw materials on rock-like materials, this paper carried out the indoor mechanical properties test and the micro-pore structure detection combining NMR and SEM. The effects of micron-silica fume (SF) on microporous structure parameters and macroscopic mechanical properties under different conditions of water-cement ratio (WCR) and sand-cement ratio (SCR) were discussed. The intrinsic relationship between parameters of different scales was analyzed. The experimental results showed that the porosity parameters of different radii gradually decreased with the increase in SF. The reduction rate of macroporous porosity was the greatest, and the decreasing rate of microporous porosity was the smallest. With the increase in SF, the microscopic characteristics of the internal surface changed from more pores, complex morphological distribution, rough surface to fewer pores, regular morphological distribution and flat and uniform surface. The box fractal dimension also showed a decreasing trend. Micro-pore structure makes a valuable contribution to the influence of SF on mechanical properties. The compressive strength and tensile strength increased with the increase in SF. The box fractal dimension and porosity of different radii were negatively correlated with mechanical strength. Different porosity parameters conformed to a good exponential relationship with mechanical properties. The research results can provide reference value and research space for subsequent rock-like material research.

17.
Cell Biosci ; 12(1): 120, 2022 Jul 30.
Article in English | MEDLINE | ID: mdl-35907898

ABSTRACT

BACKGROUND: Colorectal liver metastases (CRLM) continue to have a low survival rate. The number of CRLM regulators and clinical indicators remains limited. Long non-coding RNAs (lncRNAs) are a new master regulator of cell invasion and metastasis. However, the function and regulation mechanism of lncRNAs in colorectal cancer (CRC) metastasis are yet unknown. METHODS: To screen and identify CRLM-related lncRNAs, public transcriptome data were used. Gain and loss of function experiments were carried out to investigate the biological activities of lncRNA CRLM1 in vitro and in vivo. RNA sequencing (RNA-seq), chromatin isolation by RNA purification (ChIRP), immunofluorescence (IF), quantitative real-time PCR (qRT-PCR), western blotting, and rescue experiments were performed to explore the molecular mechanism of CRLM1. Moreover, identified the proteins, DNAs, and RNAs that interact with CRLM1. RESULTS: The investigation of lncRNA expression dynamics in CRLM, primary CRC, and normal tissues in this work resulted in identifying a series of lncRNAs associated with metastasis, including CRLM1. CRLM1 inhibited apoptosis of CRC cells and promoted liver metastasis in Balb/C nude mice. CRLM1 was weakly associated with the chromatin regions of genes involved in cell adhesion and DNA damage, and this association was bidirectionally correlated with CRLM1-regulated pro-metastatic gene expression. CRLM1 physically interacts with the hnRNPK protein and promotes its nuclear localization. CRLM1 effectively enhances hnRNPK promoter occupancy and co-regulates the expression of a panel of metastatic genes. CONCLUSIONS: The finding of the clinically significant lncRNA CRLM1 in promoting metastasis and regulating gene expression suggests a potential biomarker and target for CRLM therapy.

18.
Proc Natl Acad Sci U S A ; 105(7): 2421-6, 2008 Feb 19.
Article in English | MEDLINE | ID: mdl-18250317

ABSTRACT

The orphan nuclear receptor chicken ovalbumin upstream promoter-transcription factor II (COUP-TFII; Nr2f2) is expressed in adipose tissue in vivo and declines during differentiation. Overexpression of COUP-TFII prevents adipogenesis, whereas shRNA-mediated reduction of COUP-TFII promotes differentiation, as shown by increased lipid accumulation and elevated expression of fat cell marker proteins. Furthermore, reduction of COUP-TFII allows uncommitted fibroblasts to be differentiated into fat cells. COUP-TFII represses the expression of a number of proadipogenic factors in adipocytes, with direct action noted at the CAAT enhancer-binding protein alpha promoter. We show that COUP-TFII acts downstream of hedgehog signaling and is required for the full antiadipogenic effect of this pathway. This effect is mediated in part by interaction with GATA factors. COUP-TFII and GATA2 are physically associated and repress target gene expression in an additive manner. Taken together, our data demonstrate that COUP-TFII represents an endogenous suppressor of adipogenesis, linking antiadipogenic extracellular signals to the core transcriptional cascade.


Subject(s)
Adipogenesis , COUP Transcription Factor II/genetics , COUP Transcription Factor II/metabolism , Ovalbumin/metabolism , Promoter Regions, Genetic/genetics , Receptors, Cytoplasmic and Nuclear/metabolism , 3T3 Cells , Adipose Tissue/metabolism , Animals , Chickens , GATA Transcription Factors/metabolism , Gene Expression Regulation, Developmental , Hedgehog Proteins/metabolism , Mice , Protein Binding
19.
J Med Chem ; 64(6): 3381-3391, 2021 03 25.
Article in English | MEDLINE | ID: mdl-33688738

ABSTRACT

Nitroimidazoles are one of the most common radiosensitizers investigated to combat hypoxia-induced resistance to cancer radiotherapy. However, due to poor selectivity distinguishing cancer cells from normal cells, effective doses of radiosensitization are much closer to the doses of toxicity induced by nitroimidazoles, limiting their clinical application. In this work, a tumor-targeting near-infrared (NIR) cyanine dye (IR-808) was utilized as a targeting ligand and an NIR fluorophore tracer to chemically conjugate with different structures of hypoxia-affinic nitroimidazoles. One of the NIR fluorophore-conjugated nitroimidazoles (808-NM2) was identified to preferentially accumulate in hypoxic tumor cells, sensitively outline the tumor contour, and effectively inhibit tumor growth synergistically by chemotherapy and radiotherapy. More importantly, nitroimidazoles were successfully taken into cancer cell mitochondria via 808-NM2 conjugate to exert the synergistic effect of chemoradiotherapy. Regarding the important roles of mitochondria on cancer cell survival and metastasis under hypoxia, 808-NM2 may be hopeful to fight against hypoxic tumors.


Subject(s)
Antineoplastic Agents/therapeutic use , Breast Neoplasms/therapy , Carbocyanines/therapeutic use , Coloring Agents/therapeutic use , Nitroimidazoles/therapeutic use , Animals , Antineoplastic Agents/chemistry , Breast Neoplasms/pathology , Carbocyanines/chemistry , Chemoradiotherapy , Coloring Agents/chemistry , Female , Humans , MCF-7 Cells , Mice, Inbred BALB C , Mice, Nude , Mitochondria/drug effects , Mitochondria/pathology , Nitroimidazoles/chemistry , Tumor Hypoxia
20.
Cancer Immunol Immunother ; 59(7): 1041-7, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20182872

ABSTRACT

Heparanase is expressed in almost all advanced tumors, and therefore it may serve as a potential target for tumor therapy. Our previous study has shown that heparanase can serve as a potential universal tumor-associated antigen (TAA) for the immunotherapy of advanced tumors. Further study demonstrated that the HLA-A*0201-restricted Cytotoxic T lymphocytes (CTL) epitopes Hpa525 (PAFSYSFFV), Hpa277 (KMLKSFLKA) and Hpa405 (WLSLLFKKL) from human heparanase could induce a potent anti-tumor immune response in vitro. The present study was designed to investigate whether the above peptides could induce immune responses in mice. Our results demonstrated that the effectors from heparanase peptide-immunized mice could effectively lyse various tumor cells that were heparanase positive and HLA-A*0201 matched. We also found that these peptide-specific CTLs did not lyse autologous lymphocytes that had low heparanase activity. Further study revealed that Hpa525, Hpa277, and Hpa405 peptides increased the frequency of IFN-gamma-producing T cells as compared to a negative peptide. These results suggest that Hpa525, Hpa277, and Hpa405 peptides are novel HLA-A*0201-restricted CTL epitopes capable of inducing heparanase-specific CTLs in mice. Because heparanase is expressed in most advanced malignant tumors, Hpa525, Hpa277, and Hpa405 peptide-based vaccines may be useful for the immunotherapy of patients with advanced tumors.


Subject(s)
Epitopes, T-Lymphocyte/immunology , Glucuronidase/immunology , Neoplasms/immunology , T-Lymphocytes, Cytotoxic/immunology , Animals , Cell Line, Tumor , Cytotoxicity, Immunologic/immunology , Dendritic Cells/cytology , Dendritic Cells/immunology , Enzyme-Linked Immunosorbent Assay , HLA-A Antigens/immunology , HLA-A2 Antigen , Hep G2 Cells , Humans , Immunization/methods , Interferon-gamma/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Neoplasms/pathology , Peptides/immunology , T-Lymphocytes, Cytotoxic/cytology , T-Lymphocytes, Cytotoxic/metabolism
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