• Korean Journal of Head & Neck Oncology
• /
• v.33 no.1
• /
• pp.21-29
• /
• 2017

Methylation of CpG islands in the promoter region of genes acts as a significant mechanism of epigenetic gene silencing in head and neck squamous cell carcinoma (HNSCC). DNA methylation markers are particularly advantageous because DNA methylation is an early event in tumorigenesis, and the epigenetic modification, 5-methylcytosine, is a stable mark. In the present study, we assessed the genome-wide preliminary screening and were to identify novel methylation biomarker candidate in HNSCC. Genome-wide methylation analysis was performed on 10 HNSCC tumors using the Methylated DNA Isolation Assay (MeDIA) CpG island microarray. Validation was done using immunohistochemistry using tissue microarray of 135 independent HNSCC tumors. In addition, in vitro proliferation, migration/invasion assays, RT-PCR and immunoblotting were performed to elucidate molecular regulating mechanisms. Our preliminary validation using CpG microarray data set, immunohisto-chemistry for HNSCC tumor tissues and in vitro functional assays revealed that methylation of the Homeobox B5 (HOXB5) and H6 Family Homeobox 2 (HMX2) could be possible novel methylation biomarkers in HNSCC.

• Biomolecules & Therapeutics
• /
• v.26 no.2
• /
• pp.146-156
• /
• 2018

Spermidine is a naturally occurring polyamine compound that has recently emerged with anti-aging properties and suppresses inflammation and oxidation. However, its mechanisms of action on anti-inflammatory and antioxidant effects have not been fully elucidated. In this study, the potential of spermidine for reducing pro-inflammatory and oxidative effects in lipopolysaccharide (LPS)-stimulated macrophages and zebrafish was explored. Our data indicate that spermidine significantly inhibited the production of pro-inflammatory mediators such as nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$), and cytokines including tumor necrosis $factor-{\alpha}$ and $interleukin-1{\beta}$ in RAW 264.7 macrophages without any significant cytotoxicity. The protective effects of spermidine accompanied by a marked suppression in their regulatory gene expression at the transcription levels. Spermidine also attenuated the nuclear translocation of $NF-{\kappa}B$ p65 subunit and reduced LPS-induced intracellular accumulation of reactive oxygen species (ROS) in RAW 264.7 macrophages. Moreover, spermidine prevented the LPS-induced NO production and ROS accumulation in zebrafish larvae and was found to be associated with a diminished recruitment of neutrophils and macrophages. Although more work is needed to fully understand the critical role of spermidine on the inhibition of inflammation-associated migration of immune cells, our findings clearly demonstrate that spermidine may be a potential therapeutic intervention for the treatment of inflammatory and oxidative disorders.

• Korean Journal of Bronchoesophagology
• /
• v.8 no.1
• /
• pp.29-34
• /
• 2002

Background and Objectives : Sulfur dioxide gas is one of the major airborne Pollutants noxious to human in industrialized countries. The most vulnerable areas in the human respiratory system were the trachea and main bronchi and a gradient of decreasing damage was observed in the peripheral tracheobronchial tree. Induced functional alteration was increased mucosal permeability, and morphological changes were epithelial sloughing, intracellular edema, mitochondrial swelling, widened intercellular spaces, and ciliary cytoplamic extrusions. The laminins are a family of extracellular matrix glycoproteins localized in the basement membrane. Their primary role is cell-matrix attachment, but many additional biologic activities, including Promoting cell growth and migration, tumor growth and metastasis, wound repair, and graft survival, have been demonstrated. Materials and Methods : Histologic changes and expression of laminin in tracheal mucosa sacrificed at 1 day, 2 day, 3 day, 1 week, 2 weeks, and 3 weeks after continued SO2 exposure of 250 ppm for 30 minutes a day(to 7week) were studied in rats. In this study, mild immune reaction for laminin was noted at the apical cytoplasm of epithelial cells and basement membrane one day after a 7 week $SO_2$ exposure. The cilia and nucleoi of epithelial cells were normal and no immune reaction was noted in Goblet cells. The lamina propria of the tracheal tissue was infiltrated by monocytes and lymphocytes. Results : At 24 hours after exposure, all tracheal cells except Goblet cells revealed a mild immune reaction for laminin. No immune reactions were noted in the basement membrane. At 72 hours after exposure, mild or moderate immune reactions for laminin was seen in the tracheal cell cytoplasm. Irregular faint immune reaction for laminin was noted in the basement membrane. At 1 week after exposure, strong immune reaction for laminin was detected over all tracheal cells, and the basement membrane was seen clearly. At 2~3 weeks after exposure, strong immune reaction for laminin was seen in all tracheal epithelial cells except Goblet cells and a mild immune reaction was partly revealed in the basement membrane. Conclusion : Our study suggests that 502 produces histologic damage on the tracheal mucosa. Longer duration after exposure of $SO_2$ makes more progressive healing on the tracheal mucosa and increased immunoreactivity for laminin.

• Archives of Plastic Surgery
• /
• v.37 no.4
• /
• pp.340-345
• /
• 2010

Purpose: Recently, bioceramics have become popular as a substitute graft material for reconstruction of bony defect after trauma or tumor surgery. Among the bioceramic materials, hydroxyapatite (HA) is favored due to its biocompatibility. HA scaffold is composed of the interconnected reticular framework, macropores and micropores. Macropores play an important role in cell migration, nutrients supply and vascular ingrowth. On the other hand, a number of micropores less than $10{\mu}m$ form an irregular surface on HA scaffolds, which prevents the osteoblast from adhering and proliferating on the surface of HA scaffold. Methods: In this study, three different groups were designed for comparison. In the first group (group A), conventional method was used, in which HA pellet was applied without surface pretreatment. The second group (group B) was given a HA pellet that has been coated with crystalline HA solution prior to application. In the third group (group C), the same method was used as the second group, where the pretreated HA pellet was heated ($1250^{\circ}C$, 1 hour) before application. Osteoblast-like cells ($2{\times}10^4$/mL) were scattered onto every pellet, then they were incubated in 5% $CO_2$ incubator at $37^{\circ}C$ for twelve days. During the first three days, osteoblast cells were counted using the hemocytometer daily. ALP activity was measured on the 3, 6, 9 and 12 culture days using the spectrophotometer. Results: Under SEM, group A showed a surface with numerous micropores, and group B revealed more rough crystal surface. Group C revealed a fused crystal appearance and flattened smooth surface. In proliferation and ALP activity of osteoblast cells, group C showed better results compared to group B. Group A which lacks pretreatment of the surface showed less osteoblast proliferation and ALP activity than group C, but showed better results than group B. Conclusion: We found that crystallized HA with heat treatment method enhances the osteoblasts proliferation and differentiation on the surface of HA pellets.

• Journal of Convergence for Information Technology
• /
• v.11 no.4
• /
• pp.194-202
• /
• 2021

The leaves of Selaginella tamariscina were used for the treatment of many diseases in traditional medicine. In the study, antioxidant, anti-inflammatory, and wound healing activities of the hot-water extract(STW) and 80%ethanol extract(STE) obtained from S. tamariscina were evaluated. As a result, the polyphenol content of STW and STE were 38.108±0.766 mg/g and 17.927±1.064 mg/g, respectively. The DPPH and ABTS radical scavenging activities with the IC50 values of the STW were over 2 times lower than that of the STE. In the MTT assay, RAW264.7 cell viability of two extracts was decreased by about 6% at 1 mg/mL, whereas for HaCaT cell viability increased by 18% at 50 ㎍/mL. In addition, STW and STE suppressed the production of nitric oxide(NO), Tumor-necrosis(TNF)-��. COX-2 and PGE2 in lipopolysaccharide(LPS) induced RAW264.7 cells. Furthermore, the STE showed wound healing effect through the promotion of skin cell migration in TNF-�� stimulated human keratinocytes. These results indicated that the STW and STE have the potential to be used as a new cosmetic active ingredients in skin care.

• BMB Reports
• /
• v.55 no.2
• /
• pp.98-103
• /
• 2022

Increased mRNA levels of cancer upregulated gene (CUG)2 have been detected in many different tumor tissues using Affymetrix microarray. Oncogenic capability of the CUG2 gene has been further reported. However, the mechanism by which CUG2 overexpression promotes cancer stem cell (CSC)-like phenotypes remains unknown. With recent studies showing that pyruvate kinase muscle 2 (PKM2) is overexpressed in clinical tissues from gastric, lung, and cervical cancer patients, we hypothesized that PKM2 might play an important role in CSC-like phenotypes caused by CUG2 overexpression. The present study revealed that PKM2 protein levels and translocation of PKM2 into the nucleus were enhanced in CUG2-overexpressing lung carcinoma A549 and immortalized bronchial BEAS-2B cells than in control cells. Expression levels of c-Myc, CyclinD1, and PKM2 were increased in CUG2-overexpressing cells than in control cells. Furthermore, EGFR and ERK inhibitors as well as suppression of Yap1 and NEK2 expression reduced PKM2 protein levels. Interestingly, knockdown of β-catenin expression failed to reduce PKM2 protein levels. Furthermore, reduction of PKM2 expression with its siRNA hindered CSC-like phenotypes such as faster wound healing, aggressive transwell migration, and increased size/number of sphere formation. The introduction of mutant S37A PKM2-green fluorescence protein (GFP) into cells without ability to move to the nucleus did not confer CSC-like phenotypes, whereas forced expression of wild-type PKM2 promoted such phenotypes. Overall, CUG2-induced increase in the expression of nuclear PKM2 contributes to CSC-like phenotypes by upregulating c-Myc and CyclinD1 as a co-activator.

• The Korea Journal of Herbology
• /
• v.24 no.3
• /
• pp.161-167
• /
• 2009

Objectives : Maekmoondong-tang (MMDT), a Korean herbal medicine, has been used to treat severe dry cough in patients with bronchitis and pharyngitis. MMDT has been reported to have anti-inflammatory, anti-allergic, immunomodulatory, secretory-modulating, and metabolic regulatory actions. However, there are no evidence in regard to the effects of MMDT on carcinogenesis and metastasis. Here, we investigated the effects of 70% ethanol extract of MMDT on cell viability, apoptosis, and motility in human hepatocarcinoma HepG2 cells. Methods : Cell viability was measured using the CCK-8 assay, and the apoptosis induction was evaluated by caspase-3 activity. To detect apoptotic features, the cells treated with MMDT were stained with 4'-6-diamidino-2-phenylindole (DAPI). Cell motility was examined by Boyden chamber assay and Real-time Cell Index of Migration assay. Gelatin zymography also performed to measure matrix metalloproteinase (MMP)-2/9 activity. Results : We found that MMDT significantly inhibited cell proliferation and increased caspase-3 activity in a dose-dependent manner in HepG2 cells. Apoptotic features such as chromatin condensation and apoptotic bodies were observed in MMDT-treated cells by DAPI staining. MMDT also suppressed PMA-induced cell motility and activities of MMP-2/9. Conclusions : Our results exhibited that MMDT possess the anti-carcinogenetic and anti-metastatic activities via caspase-3 activation and down-regulation of cell motility and invasion in HepG2 cells. Therefore, these findings suggest that MMDT could be potentially applied to the prevention and treatment of cancer.

• Biomolecules & Therapeutics
• /
• v.32 no.3
• /
• pp.368-378
• /
• 2024

Cordycepin, a valuable bioactive component isolated from Cordyceps militaris, has been reported to possess anti-cancer potential and the property to enhance the effects of chemotherapeutic agents in various types of cancers. However, the ability of cordycepin to chemosensitize cholangiocarcinoma (CCA) cells to gemcitabine has not yet been evaluated. The current study was performed to evaluate the above, and the mechanisms associated with it. The study analyzed the effects of cordycepin in combination with gemcitabine on the cancer stem-like properties of the CCA SNU478 cell line, including its anti-apoptotic, migratory, and antioxidant effects. In addition, the combination of cordycepin and gemcitabine was evaluated in the CCA xenograft model. The cordycepin treatment significantly decreased SNU478 cell viability and, in combination with gemcitabine, additively reduced cell viability. The cordycepin and gemcitabine co-treatment significantly increased the Annexin V+ population and downregulated B-cell lymphoma 2 (Bcl-2) expression, suggesting that the decreased cell viability in the cordycepin+gemcitabine group may result from an increase in apoptotic death. In addition, the cordycepin and gemcitabine co-treatment significantly reduced the migratory ability of SNU478 cells in the wound healing and trans-well migration assays. It was observed that the cordycepin and gemcitabine cotreatment reduced the CD44^highCD133^high population in SNU478 cells and the expression level of sex determining region Y-box 2 (Sox-2), indicating the downregulation of the cancer stem-like population. Cordycepin also enhanced oxidative damage mediated by gemcitabine in MitoSOX staining associated with the upregulated Kelch like ECH Associated Protein 1 (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2) expression ratio. In the SNU478 xenograft model, co-administration of cordycepin and gemcitabine additively delayed tumor growth. These results indicate that cordycepin potentiates the chemotherapeutic property of gemcitabine against CCA, which results from the downregulation of its cancer-stem-like properties. Hence, the combination therapy of cordycepin and gemcitabine may be a promising therapeutic strategy in the treatment of CCA.

• Journal of Life Science
• /
• v.32 no.4
• /
• pp.271-278
• /
• 2022

The detailed mechanism by which cancer upregulated gene 2 (CUG2) overexpression induces cancer stem cell-like phenotypes is not fully understood. The downregulation of FBXW7 E3 ligase, a tumor suppressor known for its proteolytic regulation of oncogenic proteins such as cyclin E, c-Myc, Notch, and Yap1, has been frequently reported in several types of tumor tissues, including those in the large intestine, cervix, and stomach. Therefore, we investigated whether FBXW7 is involved in CUG2-induced oncogenesis. In this study, the decreased expression of FBXW7 was examined in human lung adenocarcinoma A549 (A549-CUG2) and human bronchial BEAS-2B cells (BEAS-CUG2) overexpressing CUG2 and compared with control cells stably expressing an empty vector (A549-Vec or BEAS-Vec). Treatment with MG132 (a proteosome inhibitor) prevented the degradation of FBXW7 and Yap1 proteins, which are substrates of the FBXW7 E3 ligase. To address the role of Fbxw7 in the development of cancer stem cell (CSC) phenotypes, we suppressed Fbxw7 protein levels using its siRNA. We observed that decreased levels of FBXW7 enhanced cell migration, invasion, and spheroid size and number in A549-Vec and BEAS-Vec cells. The enforced expression of FBXW7 produced the opposite results in A549-CUG2 and BEAS-CUG2 cells. Furthermore, the downregulation of FBXW7 elevated the activities of EGFR, Akt, and ERK1/2 and upregulated β-catenin, Yap1, and NEK2, while the enforced expression of FBXW7 generated the opposite results. We thus propose that FBXW7 downregulation induced by CUG2 confers CSC-like phenotypes through the upregulation of both the EGFR-ERK1/2 and β-catenin-Yap1-NEK2 signaling pathways.

• Radiation Oncology Journal
• /
• v.19 no.2
• /
• pp.181-189
• /
• 2001

Purpose : Changes in the balance between MMP and TIMP can have a profound effect on the composition in the extracellular matrix (ECM) and affect various cellular functions including adhesion, migration, differentiation of cells, and fibrosis and invasion and metastasis of cancer cells. Radiation therapy is a popular treatment modality for benign and malignant tumor, but the study for radiation effect on MMP and TIMP is scarce. In the current study, we have examined the expression of TIMP in fibrosis-prone (C57BL/6) mice after radiation. Methods and Materials : Adult female mice of $10\~12$ weeks were used. The whole body were irradiated using a Varian CL-4/100 with 2 and 10 Gy. Immunohistochemical staining was peformed according to Avidin Biotin complex method and evaluated by observing high power field. For TIMP-1, TIMP-2 antibodies, reactivity was assessed in the parenchymal cell and in the stromal cell. The scale of staining was assessed by combining the quantitative and qualiative intensity of staining. Results : TIMP-1 immunoreactivity did not change in lung. But, in liver, TIMP-1 immunoreactivity was localized in cytoplasm of hepatocyte and Kupffer cell. in kidney, TIMP-1 immunoreactivity was localized in cytoplasm of some tubular cell. Temporal variations were not seen. Dose-response relationship was not seen except kidney. TIMP-2 immunoreactivity in lung was a score (++) at 0 Gy and elevated to a score (+++) at 2 Gy. TIMP-2 immunoreactivity was a score (++) in liver at 0 Gy. TIMP-2 immunoreactivity was localized in cytoplasm of hepatocyte and Kupffer cell as same as patterns of TIMP-1 immunoreactivity. The TIMP-2 immunoreactivity in liver was elevated to (+++) at 2 Gy. Immunoreactivity to TIMP-2 in kidney was a score (+++) at 0 Gy and was not changed at 10 Gy. The score of TIMP-2 immunoreactivity was reduced to (++) at 2 Gy. TIMP-2 immunoreactivity was confined to tubules in kidney. Temporal variation of TIMP-2 immunoreactivity was irregular. Dose-response relationship of TIMP-2 immunoreactivity was not seen. Conclusions : Differences between intensity of expression of TIMP-1 and TIMP-2 in each organ was present. Expression of TIMP was localized to specific cell in each organ. Irradiation increased TIMP-1 immunoreactivity in the liver and the kidney. Irradiation increased TIMP-2 immunoreactivity in the lung. But, in the liver and the kidney, TIMP-2 expression to radiation was irregular. Temporal variation of TIMP-2 immunoreactivity was irregular. Dose-response relationship of TIHP-2 immunoreactivity was not seen. In the future, we expect that the study of immunohistochemical staining of longer period of postirradiation and quantitative analysis using western blotting and northern blotting could define the role of TIMP in the radiation induced tissue fibrosis.