• Journal of Animal Science and Technology
• /
• v.62 no.2
• /
• pp.239-246
• /
• 2020

Microorganism residing in the gut has been known to have important roles in the animal body. Microbes and host microenvironment are highly related with host's health including energy metabolism and immune system. Moreover, it reported that gut microbiome is correlated with diseases like obesity in human and dogs. There have been many studies to identify and characterize microbes and their genes in human body. However, there was little information of microbiome in companion animals. Here, we investigated microbiota communities in feaces from twenty - four Beagles (aged 2 years old) and analyzed the taxonomy profile using metagenomics to study the difference among gut microbiome based on body condition score (BCS). gDNA was isolated from feaces, sequenced and clustered. Taxonomy profiling was performed based on the NCBI database. BCS was evaluated once a week according to the description provided by World Small Animal Veterinary Association. Firmicutes phylum was the most abundant followed by Bacteroidetes, Fusobacteria, Proteobacteria and Actinobacteria. That main microbiota in gut were differently distributed based on the BCS. Fusobacteria has been known to be associated with colon cancer in human. Interestingly, Fusobacteria was in the third level from the top in healthy dog's gut microbiome. In addition, Fusobacteria was especially higher in overweight dogs which had 6 scales of BCS. Species Fusobacterium perfoetens was also more abundant when dogs were in BCS 6. It implied that F. perfoetens would be positively related with overweight in dogs. These finding would contribute to further studies of gut microbiome and their functions to improve dog's diets and health condition.

• Proceedings of the KOR-BRONCHOESO Conference
• /
• 1993.05a
• /
• pp.85-85
• /
• 1993

The clinical staging system for laryngeal cancers is not sufficient for prognosticator due to different biologic characteristics and their microenvironment according to primary sites. For determining the prognosticators, the authors peformed immunohistochemical staining to EGFR, p53 protein, and pRB in 40 cases of surgically treated squamous cell carcinomas of larynx in our institute during the past 5 years. The results are as followings; 1. The positive expression rate of p53 protein and negative expression rate of pRB showed correlations with clinical parameters. 2. The three-year survival rate for p53 protein positive cases was worse than the p53 protein negative cases. 3. Expression rate of EGFR was not correlated with the clinical parameters. As a conclusion, expression rates of p53 protein and pRB not only reflect well the biologic behavior of laryngeal cancer, but correlate closely with the tumor factors. Therefore they may be useful as the prognosticator to predict the malignant potency of laryngeal squamous cell carcinomas.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.27 no.4
• /
• pp.314-320
• /
• 2001

Matrix metalloproteinases have long been viewed as ideal candidates for proteinases that enables tumor cells to permeated basement membrane defenses and invade surrounding tissue. There is growing evidence that the MMPs have an expanded role, as they are important for the creation and maintenance of a microenvironment that facilitates growth and angiogenesis of tumors at primary and metastatic sites. MT-MMPs are not secreted but instead remaining attached to cell surfaces. Although not all of the MT-MMPs are fully characterized, MT-MMPs have important role in localizing and activating secreted MMPs. The MMP genes are transcriptionally responsive to a wide variety of oncogene, growth factors, cytokine, and hormones. Currently, a number of MMP inhibitors are being developed and some have reached clinical trials as anti-metastatic or anti-cancer therapies. MT1-MMP is involved in the activation of proMMP-2. MT1-MMP is significant not only as a tumor marker but as a new target for chemotherapy against cancer. The purpose of this study was to evaluate the effects of protein kinase C inhibitor(genistein) on the proliferation of HT1080 and expression of MT1-MMP mRNA. Human fibrosarcoma cell line HT1080 was cultured and divided 2 groups. The experimental group was treated with $100{\mu}M$ genistein and incubated 12h, 24h for $[3^H]-thymidine$ uptake assay and northern hybridization individually. And the control group was treated with same amount of PBS for the above procedures. $[3^H]-thymidine$ incorporation was measured with ${\beta}$ ray detector. And RT-PCR and northern blotting for MT1-MMP mRNA was performed. The results were as follows 1. $[3^H]-thymidine$ uptake was reduced in experimental group with statistical significance. 2. MT1-MMP mRNA expression was significantly reduced in experimental group. These results showed that protein kinase C inhibitor (genistein) inhibited proliferation of HT1080 and almost completely blocked transcription of MT1-MMP mRNA. So, it is possible to use the protein kinase inhibitor (genistein) as anti-metastatic and anti-proliferative agent.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.8
• /
• pp.4031-4036
• /
• 2012

Background: The negative signaling provided by interactions of the co-inhibitory molecule, programmed death-1 (PD-1), and its ligands, B7-H1 (PD-L1) and B7-DC (PD-L2), is a critical mechanism contributing to tumor evasion; blockade of this pathway has been proven to enhance cytotoxic activity and mediate antitumor therapy. Here we evaluated the anti-tumor efficacy of AAV-mediated delivery of the extracellular domain of murine PD-1 (sPD-1) to a tumor site. Material and Methods: An rAAV vector was constructed in which the expression of sPD-1, a known negative regulator of TCR signals, is driven by human cytomegalovirus immediate early promoter (CMV-P), using a triple plasmid transfection system. Tumor-bearing mice were then treated with the AAV/sPD1 construct and expression of sPD-1 in tumor tissues was determined by semi quantitative RT-PCR, and tumor weights and cytotoxic activity of splenocytes were measured. Results: Analysis of tumor homogenates revealed sPD-1 mRNA to be significantly overexpressed in rAAV/sPD-1 treated mice as compared with control levels. Its use for local gene therapy at the inoculation site of H22 hepatoma cells could inhibit tumor growth, also enhancing lysis of tumor cells by lymphocytes stimulated specifically with an antigen. In addition, PD-1 was also found expressed on the surfaces of activated CD8+ T cells. Conclusion: This study confirmed that expression of the soluble extracellular domain of PD-1 molecule could reduce tumor microenvironment inhibitory effects on T cells and enhance cytotoxicity. This suggests that it might be a potential target for development of therapies to augment T-cell responses in patients with malignancies.

• Journal of Life Science
• /
• v.29 no.5
• /
• pp.530-536
• /
• 2019

Glioblastoma (GBM) is the most incurable brain cancer derived from the transformed glial cells. Standard anti-GBM treatment, including surgery and chemoradiotherapy, does not ensure good prognosis for the patients with GBM, because successful therapy is often impeded by presence of glioma stem cells (GSCs). GSCs, which is generally divided into proneural (PN) and mesenchymal (MES) subtype, are understood as subpopulation of cancer cells responsible for GBM initiation, progression and recurrence after standard treatments. In the present study, we demonstrate that PN subtype GSCs differentially transit to MES subtype GSCs by specific cytokines. The expression of CD44, a marker of MES subtype GSCs, was observed when GSC11 PN subtype GSCs were exposed to tumor necrosis factor alpha ($TNF-{\alpha}$) cytokine and GSC23 PN subtype GSCs were treated to transforming growth factor beta 1 ($TGF-{\beta}1$) cytokine. Ivy glioblastoma atlas project (Ivy GAP) bioinformatics database showed that $TNF-{\alpha}$ and $TGF-{\beta}1$ were highly expressed in necrotic region and perivascular region, respectively. In addition, $TNF-{\alpha}$ signaling was relatively upregulated in necrotic region, while $TGF-{\beta}$ signaling was increased in perivascular region. Taken together, our observations suggest that MES subtype GSCs can be derived from various PN subtype GSCs by multimodal cytokine stimuli provided by neighboring tumor microenvironment.

• Tuberculosis and Respiratory Diseases
• /
• v.63 no.3
• /
• pp.242-250
• /
• 2007

Background: Abnormal angiogenesis can induce hypoxia within a highly proliferating tumor mass, and these hypoxic conditions can in turn create clinical problems, such as resistance to chemotherapy. However, the mechanism by which hypoxia induces these changes has not yet been determined. Therefore, this study was conducted to determine how hypoxia induces changes in cell viability and extracellular microenvironments in an in vitro culture system using non-small cell lung cancer cells. Methods: The non-small cell lung cancer cell line, A549 was cultured in DMEM or RPMI-1640 media that contained fetal bovine serum. A decrease in the oxygen tension of the media that contained the culture was then induced in a hypoxia microchamber using a $CO_2-N_2$ gas mixture. A gas analysis and an MTT assay were then conducted. Results: (1) The decrease in oxygen tension was checked the anaerobic gas mixture for 30 min and then reoxygenation was induced by adding a 5% $CO_2-room$ air gas mixture to the chamber. (2) Purging with the anaerobic gas mixture was found to decrease the further oxygen tension of cell culture media. (3) The low oxygen tension resulted in a low pH, lactic acidosis and a decreased glucose concentration in the media. (4) The decrease in glucose concentration that was observed as a result of hypoxia was markedly different when different types of media were evaluated. (5) The decrease in oxygen tension inhibited proliferation of A549 cells. Conclusion: These data suggests that tumor hypoxia is associated with acidosis and hypoglycemia, which have been implicated in the development of resistance to chemotherapy and radiotherapy.

• Tuberculosis and Respiratory Diseases
• /
• v.66 no.3
• /
• pp.178-185
• /
• 2009

Background: Epigallocatechin-3-gallate (EGCG) is the major catechin in green tea, and has shown antiproliferative, antiangiogenic, antimetastatic and cell cycle pertubation activity in various tumor models. Hypoxia can be induced because angiogenesis is insufficient for highly proliferating cancer. Hypoxia-inducible factor-1$\alpha$ (HIF-1$\alpha$) and its downstream target, vascular endothelial growth factor (VEGF), are important for angiogenesis, tumor growth and metastasis. The aim of this study was to determine how hypoxia could cause changes in the cellular phenomena and microenvironment in a non-small cell culture system and to examine the effects of EGCG on a HIF-1$\alpha$ and VEGF in A549 cell line. Methods: A549 cells, a non-small cell lung cancer cell line, were cultured with DMEM and 10% fetal bovine serum. A decrease in oxygen tension was induced using a hypoxia microchamber and a $CO_2-N_2$ gas mixture. Gas analysis and a MTT assay were performed. The A549 cells were treated with EGCG (0, 12.5, 25, 50 ${\mu}mol/L$), and then examined by real-time-PCR analysis of HIF-1$\alpha$, VEGF, and $\beta$-actin mRNA. Results: Hypoxia reduced the proliferation of A549 cells from normoxic conditions. EGCG inhibited HIF-1$\alpha$ transcription in A549 cells in a dose-dependent manner. Compared to HIF-1$\alpha$, VEGF was not inhibited by EGCG. Conclusion: HIF-1$\alpha$ can be inhibited by EGCG. This suggests that targeting HIF-1$\alpha$ with a EGCG treatment may have therapeutic potential in non-small cell lung cancers.

• IMMUNE NETWORK
• /
• v.3 no.1
• /
• pp.29-37
• /
• 2003

Background: CC chemokine receptor (CCR) 7 and cognate CCR7 ligands, CCL21 (formerly secondary lymphoid tissue chemokine [SLC]) and CCL19 (formerly Epstein-Barr virus-induced molecule 1 ligand chemokine [ELC]), were known to establish microenvironment for the initiation of immune responses in secondary lymphoid tissue. As described previously, coadministration of DNA vaccine with CCR7 ligand-encoding plasmid DNA elicited enhanced humoral and cellular immunity via increasing the number of dendritic cells (DC) in secondary lymphoid tissue. The author hypothesized here that CCR7 ligand DNA could effectively expand memory CD4+ T cells to protect from viral infection likely via increasing DC number. Methods: To evaluate the effect of CCR7 ligand DNA on the expansion of memory CD4+ T cells, DO11.10.BALB/c transgenic (Tg)-mice, which have highly frequent ovalbumin $(OVA)_{323-339}$ peptide-specific CD4+ T cells, were used. Tg-mice were previously injected with CCR7 ligand DNA, then immunized with $OVA_{323-339}$ peptide plus complete Freund's adjuvant. Subsequently, memory CD4+ T cells in peripheral blood lymphocytes (PBL) were analyzed by FACS analysis for memory phenotype ($CD44^{high}$ and CD62 $L^{low}$) at memory stage. Memory CD4+ T cells recruited into inflammatory site induced with OVA-expressing virus were also analyzed. Finally, the protective efficacy against viral infection was evaluated. Results: CCR7 ligand DNA-treated Tg-mice showed more expanded $CD44^{high}$ memory CD4+ T cells in PBL than control vector-treated animals. The increased number of memory CD4+ T cells recruited into inflammatory site was also observed in CCR7 ligand DNA-treated Tg-mice. Such effectively expanded memory CD4+ T cell population increased the protective immunity against virulent viral infection. Conclusion: These results document that CCR7 and its cognate ligands play an important role in intracellular infection through establishing optimal memory T cell. Moreover, CCR7 ligand could be useful as modulator in DNA vaccination against viral infection as well as cancer.

• Gut and Liver
• /
• v.12 no.6
• /
• pp.682-693
• /
• 2018

Background/Aims: Intestinal barrier dysfunction is a hallmark of inflammatory bowel diseases (IBDs) such as ulcerative colitis. This dysfunction is caused by increased permeability and the loss of tight junctions in intestinal epithelial cells. The aim of this study was to investigate whether estradiol treatment reduces colonic permeability, tight junction disruption, and inflammation in an azoxymethane (AOM)/dextran sodium sulfate (DSS) colon cancer mouse model. Methods: The effects of $17{\beta}$-estradiol (E2) were evaluated in ICR male mice 4 weeks after AOM/DSS treatment. Histological damage was scored by hematoxylin and eosin staining and the levels of the colonic mucosal cytokine myeloperoxidase (MPO) were assessed by enzyme-linked immunosorbent assay (ELISA). To evaluate the effects of E2 on intestinal permeability, tight junctions, and inflammation, we performed quantitative real-time polymerase chain reaction and Western blot analysis. Furthermore, the expression levels of mucin 2 (MUC2) and mucin 4 (MUC4) were measured as target genes for intestinal permeability, whereas zonula occludens 1 (ZO-1), occludin (OCLN), and claudin 4 (CLDN4) served as target genes for the tight junctions. Results: The colitis-mediated induced damage score and MPO activity were reduced by E2 treatment (p<0.05). In addition, the mRNA expression levels of intestinal barrier-related molecules (i.e., MUC2, ZO-1, OCLN, and CLDN4) were decreased by AOM/DSS-treatment; furthermore, this inhibition was rescued by E2 supplementation. The mRNA and protein expression of inflammation-related genes (i.e., KLF4, NF-${\kappa}B$, iNOS, and COX-2) was increased by AOM/DSS-treatment and ameliorated by E2. Conclusions: E2 acts through the estrogen receptor ${\beta}$ signaling pathway to elicit anti-inflammatory effects on intestinal barrier by inducing the expression of MUC2 and tight junction molecules and inhibiting pro-inflammatory cytokines.

• Korean Journal of Clinical Laboratory Science
• /
• v.50 no.4
• /
• pp.391-398
• /
• 2018

Mesenchymal stem cells (MSCs) are an attractive resource for refractory patients because of their anti-inflammatory/immunomodulatory capability and multi-lineage differentiation potential. The transplantation of MSCs has led to positive results in preclinical and clinical application to various diseases, including autoimmune disease, cardiovascular disease, cancer, liver cirrhosis, and ischemic stroke. On the other hand, studies have shown that paracrine factors, not direct cell replacement for damaged cells or tissue, are the main contributors in MSC-based therapy. More recently, evidence has indicated that MSC-derived exosomes play crucial roles in regulating the paracrine factors that can mediate tissue regeneration via transferring nucleic acids, proteins, and lipids to the local microenvironment and cell-to-cell communication. The use of these exosomes is likely to be beneficial for the therapeutic application of MSCs because their use can avoid harmful effects, such as tumor formation involved in cell transplantation. Therefore, therapeutic applications using MSC-derived exosomes might be safe and efficient strategies for regenerative medicine and tissue engineering. This review summarizes the recent advances and provides a comprehensive understanding of the role of MSC-derived exosomes as a therapeutic agent.