Tumor necrosis factor-α downregulates the REIC/Dkk-3 tumor suppressor gene in normal human skin keratinocytes.

Our previous studies revealed that REIC/Dkk-3 was expressed various tissues, including skin keratinocytes. The aim of the present study was to identify the factors that regulate the expression of the dickkopf Wnt signaling pathway inhibitor 3 (REIC/Dkk‑3) tumor suppressor gene in normal human skin keratinocytes (NHKs). Several growth factors and cytokines that have previously been reported to be involved in the growth and differentiation of keratinocytes were screened as potential regulators.

Expression of tumor suppressor REIC/Dkk-3 by a newly improved adenovirus vector with insertion of a hTERT promoter at the 3'-side of the transgene.

Reduced expression in immortalized cells (REIC)/Dickkopf-3 (Dkk-3) overexpression, induced using an adenovirus (Ad)-REIC, has been revealed to have a dramatic therapeutic effect on multiple types of cancer. To achieve an improved therapeutic effect from Ad-REIC on cancer, our group previously developed an enhanced gene expression system, the C-TSC cassette [cytomegalovirus (CMV)-RU5' located upstream (C); another promoter unit composed of triple tandem promoters, human telomerase reverse transcriptase (hTERT), simian virus 40 and CMV, located downstream of the cDNA (TSC); plus a polyadenylation (polyA) signal]. When applied to the conventional Ad-REIC, this novel system induced the development of an enhanced product, Ad-C-TSC-REIC, which exhibited a noticeable anticancer effect.

Robust cancer-specific gene expression by a novel cassette with hTERT and CMV promoter elements.

We developed and validated a novel hTERT/CMV promoter element-driven gene expression cassette that can robustly enhance cancer-specific gene expression. The following gene expressional elements were located in tandem within the plasmid construct: [hTERT core promoter, cytomegalovirus (CMV) minimized promoter, RU5' sequence, an inserted gene, BGH polyA, hTERT enhancer]; this is hereafter referred to as the hT/Cm-R-hT construct. Using various human cancer cell lines and normal cells, the cancer-specific transcription of the green fluorescent protein (GFP) gene was examined by western blotting and fluorescence microscopy.

Identification of an S100A8 Receptor Neuroplastin-β and its Heterodimer Formation with EMMPRIN.

We previously reported a positive feedback loop between S100A8/A9 and proinflammatory cytokines mediated by extracellular matrix metalloproteinase inducer, an S100A9 receptor. Here, we identify neuroplastin-β as an unreported S100A8 receptor. Neuroplastin-β and extracellular matrix metalloproteinase inducer form homodimers and a heterodimer, and they are co-localized on the surface of cultured normal human keratinocytes.

Active Secretion of Dimerized S100A11 Induced by the Peroxisome in Mesothelioma Cells.

S100A11, a small Ca binding protein, acts extracellularly as a mediator of cancer progression. That raises the question of how a protein that lacks the classical secretory signal is able to be secreted outside cells without being damaged. Some insights into this question have been obtained, and there has been accumulating evidence indicating a pivotal role of a non-classical vesicle-mediated pathway using lysosomes or peroxisomes for the protein secretion.

NRF2 Regulates PINK1 Expression under Oxidative Stress Conditions.

Mutations of the PTEN-induced putative kinase 1 (PINK1) gene are a cause of autosomal recessive forms of Parkinson's disease. Recent studies have revealed that PINK1 is an essential factor for controlling mitochondrial quality, and that it protects cells from oxidative stresses. Although there has been considerable progress in the elucidation of various aspects of PINK1 protein regulation such as activation, stability and degradation, the transcriptional regulation of PINK1 mRNA under stress conditions remains unclear.

DNAX-activating protein 10 (DAP10) membrane adaptor associates with receptor for advanced glycation end products (RAGE) and modulates the RAGE-triggered signaling pathway in human keratinocytes.

The receptor for advanced glycation end products (RAGE) is involved in the pathogenesis of many inflammatory, degenerative, and hyperproliferative diseases, including cancer. Previously, we revealed mechanisms of downstream signaling from ligand-activated RAGE, which recruits TIRAP/MyD88. Here, we showed that DNAX-activating protein 10 (DAP10), a transmembrane adaptor protein, also binds to RAGE.

Dramatic increase in expression of a transgene by insertion of promoters downstream of the cargo gene.

For expression of genes in mammalian cells, various vectors have been developed using promoters including CMV, EF-1α, and CAG promoters and have been widely used. However, such expression vectors sometimes fail to attain sufficient expression levels depending on the nature of cargo genes and/or on host cell types. In the present study, we aimed to develop a potent promoter system that enables high expression levels of cargo genes ubiquitously in many different cell types.

Anti-cancer effects of REIC/Dkk-3-encoding adenoviral vector for the treatment of non-small cell lung cancer.

Objectives: REIC/Dkk-3 is down-regulated in a broad range of human cancer cells and is considered to function as a tumor suppressor. We previously reported that REIC/Dkk-3-expressing adenovirus vector (Ad-REIC) induced endoplasmic reticulum (ER) stress and cancer-specific apoptosis in human prostate cancer. In this study, we examined the therapeutic impact of Ad-REIC on non-small cell lung cancer (NSCLC).

A novel gene expression system strongly enhances the anticancer effects of a REIC/Dkk-3-encoding adenoviral vector.

Gene expression systems with various promoters, including the cytomegalovirus (CMV) promoter, have been developed to increase the gene expression in a variety of normal and cancer cells. In particular, in the clinical trials of cancer gene therapy, a more efficient and robust gene expression system is required to achieve sufficient therapeutic outcomes. By inserting the triple translational enhancer sequences of human telomerase reverse transcriptase (hTERT), Simian virus 40 (SV40) and CMV downstream of the sequence of the BGH polyA, we were able to develop a novel gene expression system that significantly enhances the expression of the genes of interest.

Inhibition of RAGE signaling through the intracellular delivery of inhibitor peptides by PEI cationization.

The receptor for advanced glycation end products (RAGE) is a multi-ligand cell surface receptor and a member of the immunoglobulin superfamily. RAGE is involved in a wide range of inflammatory, degenerative and hyper-proliferative disorders which span over different organs by engaging diverse ligands, including advanced glycation end products, S100 family proteins, high-mobility group protein B1 (HMGB1) and amyloid β. We previously demonstrated that the cytoplasmic domain of RAGE is phosphorylated upon the binding of ligands, enabling the recruitment of two distinct pairs of adaptor proteins, Toll-interleukin 1 receptor domain-containing adaptor protein (TIRAP) and myeloid differentiation protein 88 (MyD88).

SARM1 and TRAF6 bind to and stabilize PINK1 on depolarized mitochondria.

Mutations in PTEN-induced putative kinase 1 (PINK1) or parkin cause autosomal recessive forms of Parkinson's disease. Recent work suggests that loss of mitochondrial membrane potential stabilizes PINK1 and that accumulated PINK1 recruits parkin from the cytoplasm to mitochondria for elimination of depolarized mitochondria, which is known as mitophagy. In this study, we find that PINK1 forms a complex with sterile α and TIR motif containing 1 (SARM1) and tumor necrosis factor receptor-associated factor 6 (TRAF6), which is important for import of PINK1 in the outer membrane and stabilization of PINK1 on depolarized mitochondria.

Design and synthesis of a series of α-benzyl phenylpropanoic acid-type peroxisome proliferator-activated receptor (PPAR) gamma partial agonists with improved aqueous solubility.

In the continuing study directed toward the development of peroxisome proliferator-activated receptor gamma (hPPARγ) agonist, we attempted to improve the water solubility of our previously developed hPPARγ-selective agonist 3, which is insufficiently soluble for practical use, by employing two strategies: introducing substituents to reduce its molecular planarity and decreasing its hydrophobicity via replacement of the adamantyl group with a heteroaromatic ring. The first approach proved ineffective, but the second was productive. Here, we report the design and synthesis of a series of α-benzyl phenylpropanoic acid-type hPPARγ partial agonists with improved aqueous solubility.

DOCK7 is a critical regulator of the RAGE-Cdc42 signaling axis that induces formation of dendritic pseudopodia in human cancer cells.

Cellular migration is a fundamental process linked to cancer metastasis. Growing evidence indicates that the receptor for advanced glycation end products (RAGE) plays a pivotal role in this process. With regard to downstream signal transducers of RAGE, diaphanous-1 and activated small guanine nucleotide triphosphatases, Rac1 and Cdc42, have been identified.

S100A9 is a novel ligand of EMMPRIN that promotes melanoma metastasis.

The calcium-binding proteins S100A8 and S100A9 can dimerize to form calprotectin, the release of which during tissue damage has been implicated in inflammation and metastasis. However, receptor(s) mediating the physiologic and pathophysiologic effects of this damage-associated "danger signal" are uncertain. In this study, searching for candidate calprotectin receptors by affinity isolation-mass spectrometry, we identified the cell surface glycoprotein EMMPRIN/BASIGIN (CD147/BSG).

Preclinical biodistribution and safety study of reduced expression in immortalized cells/Dickkopf-3-encoding adenoviral vector for prostate cancer gene therapy.

The biodistribution and safety of adenoviral vectors encoding the human REIC/Dkk-3 tumor suppressor gene (Ad-REIC) were examined in this preclinical study for in situ prostate cancer gene therapy. First, the in vitro apoptotic effects of Ad-REIC in normal and cancer cells derived from the prostate and liver were examined. Significant apoptotic effects were observed at 100 MOI (multiplicity of infection) in prostate cancer cells (LNCaP, PC3) and hepatoma cells (HEP3B and HEPG2); however, no effects were seen in normal cells.

S100A7 promotes the migration and invasion of osteosarcoma cells via the receptor for advanced glycation end products.

Osteosarcoma is the most common malignant tumor of bone in childhood and adolescence. Despite intensive research for new therapies, the outcome in patients with metastasis remains extremely poor. S100 proteins are involved in the proliferation, cell cycle progression and metastasis of numerous malignant tumors, including osteosarcoma.

REIC/Dkk-3-encoding adenoviral vector as a potentially effective therapeutic agent for bladder cancer.

Bladder cancer is one of the most common urogenital malignancies. The intravesical instillation of anticancer agents is an attractive strategy to treat a superficial lesion or floating/disseminated cancer cells after transurethral operation. An adenovirus carrying REIC/Dkk-3, a tumor suppressor gene (Ad-REIC), exhibits cancer-specific apoptotic effects in various types of cancer cells.

Preclinical safety and efficacy of in situ REIC/Dkk-3 gene therapy for prostate cancer.

The preclinical safety and therapeutic efficacy of adenoviral vectors that express the REIC/Dkk-3 tumor suppressor gene (Ad-REIC) was examined for use in prostate cancer gene therapy. The Ad-human (h) and mouse (m) REIC were previously demonstrated to induce strong anti-cancer effects in vitro and in vivo, and we herein report the results of two in vivo studies. First, intra-tumor Ad-hREIC administration was examined for toxicity and therapeutic effects in a subcutaneous tumor model using the PC3 prostate cancer cell line.

DNA methylation status of REIC/Dkk-3 gene in human malignancies.

Purpose: The REIC (reduced expression in immortalized cells)/Dkk-3 is down-regulated in various cancers and considered to be a tumor suppressor gene. REIC/Dkk-3 mRNA has two isoforms (type-a,b). REIC type-a mRNA has shown to be a major transcript in various cancer cells, and its promoter activity was much stronger than that of type-b.

Partial sensitization of human bladder cancer cells to a gene-therapeutic adenovirus carrying REIC/Dkk-3 by downregulation of BRPK/PINK1.

REIC/Dkk-3 is a tumor suppressor gene that was first identified as a gene downregulated in association with immortalization of normal human fibroblasts. We have demonstrated that an adenovirus carrying REIC/Dkk-3 (Ad-REIC) showed a tumor-specific killing effect on a wide range of cancers. However, some human cancers, bladder cancers in particular, are resistant to Ad-REIC.

A novel tumor suppressor, REIC/Dkk-3 gene identified by our in vitro transformation model of normal human fibroblasts works as a potent therapeutic anti-tumor agent.

Reduced Expression in Immortalized Cell (REIC) was cloned by subtractive hybridization method as a gene whose expression is reduced in many human immortalized and neoplastic tumor cells. The REIC, when over-expressed by an adenovirus (Ad-REIC), exhibited a dramatic therapeutic effect on a wide variety of human cancers through a mechanism triggered by ER-stress-mediated JNK activation. In addition to this direct effect on cancer cells, Ad-REIC exerted another cytotoxicity on human cancers, an indirect host-mediated effect due to overproduction of IL-7 by mis-targeted normal cells.

Tumor suppressor REIC/Dkk-3 interacts with the dynein light chain, Tctex-1.

REIC/Dkk-3 is a member of the Dickkopf family proteins known as Wnt-antagonists, and REIC/Dkk-3 expression is downregulated in a broad range of cancer types. REIC/Dkk-3 acts as a tumor suppressor in multiple cancer cell lines by inducing apoptosis through endoplasmic reticulum (ER) stress signaling. However, the intracellular interaction partners of REIC/Dkk-3 have not been fully elucidated.

TIRAP, an adaptor protein for TLR2/4, transduces a signal from RAGE phosphorylated upon ligand binding.

The receptor for advanced glycation end products (RAGE) is thought to be involved in the pathogenesis of a broad range of inflammatory, degenerative and hyperproliferative diseases. It binds to diverse ligands and activates multiple intracellular signaling pathways. Despite these pivotal functions, molecular events just downstream of ligand-activated RAGE have been surprisingly unknown.

Epigenetic silencing of microRNA-34b/c plays an important role in the pathogenesis of malignant pleural mesothelioma.

Purpose: Malignant pleural mesothelioma (MPM) is an aggressive tumor with a dismal prognosis. Unlike other malignancies, TP53 mutations are rare in MPM. Recent studies have showed that altered expression of microRNA (miRNA) is observed in human malignant tumors.