• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.9
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• pp.3952-3961
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• 2012

Developing computational methods for identifying cell cycle-regulated genes has been one of important topics in systems biology. Most of previous methods consider the periodic characteristics of expression signals to identify the cell cycle-regulated genes. However, we assume that cell cycle-regulated genes are relatively active having relatively many interactions with each other based on the underlying cellular network. Thus, we are motivated to apply the theory of multivariate phase synchronization to the cell cycle expression analysis. In this study, we apply the method known as "Self-Organizing Maps with statistical Phase Synchronization (SOMPS)", which is the combination of self-organizing map and multivariate phase synchronization, producing several subsets of genes that are expected to have interactions with each other in their subset (Kim, 2008). Our evaluation experiments show that the SOMPS algorithm is able to detect cell cycle-regulated genes as much as one of recently reported method that performs better than most existing methods.

• Biomolecules & Therapeutics
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• v.26 no.3
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• pp.328-334
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• 2018

Because of the unsatisfactory treatment options for breast cancer (BC), there is a need to develop novel therapeutic approaches for this malignancy. One such strategy is chemotherapy using non-toxic dietary substances and botanical products. Studies have shown that Panduratin A (PA) possesses many health benefits, including anti-inflammatory, anti-bacterial, anti-oxidant and anticancer activities. In the present study, we provide evidence that PA treatment of MCF-7 BC cells resulted in a time- and dose-dependent inhibition of cell growth with an $IC_{50}$ of $15{\mu}M$ and no to little effect on normal human MCF-10A breast cells. To define the mechanism of these anti-proliferative effects of PA, we determined its effect critical molecular events known to regulate the cell cycle and apoptotic machinery. Immunofluorescence and flow cytometric analysis of Annexin V-FITC staining provided evidence for the induction of apoptosis. PA treatment of BC cells resulted in increased activity/expression of mitochondrial cytochrome C, caspases 7, 8 and 9 with a significant increase in the Bax:Bcl-2 ratio, suggesting the involvement of a mitochondrial-dependent apoptotic pathway. Furthermore, cell cycle analysis using flow cytometry showed that PA treatment of cells resulted in G0/G1 arrest in a dose-dependent manner. Immunoblot analysis data revealed that, in MCF-7 cell lines, PA treatment resulted in the dose-dependent (i) induction of $p21^{WAF1/Cip1}$ and p27Kip1, (ii) downregulation of Cyclin dependent kinase (CDK) 4 and (iii) decrease in cyclin D1. These findings suggest that PA may be an effective therapeutic agent against BC.

• Journal of Ginseng Research
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• v.28 no.1
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• pp.39-44
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• 2004

The present study is to determine whether the Red-ginseng extract has a proliferative or cytotoxic effect on the human neuronal stem cells(hNSCs). The hNSCs were grown and incubated with different doses of Red-ginseng extract. We tested the proliferative or cytotoxic effects by MTT and FACS analysis. Cell viability cell cycle analysis, DNA fragmentation, and bax or PARP expressions were evaluated. The hNSCs showed a proliferafe trend with its peak concentration at 0.3 $\mu\textrm{g}$/$m\ell$. Beyond this point, higher doses decreased viabilities and showed a cytotoxic effect at 10 $\mu\textrm{g}$/$m\ell$. There was a tendency of increased S and G2/M phases during cell proliferation. In a cytotoxic condition, decreased S phase and increased G0/G1 phases were noted, suggesting cell cycle arrest. The cytotoxic effect was associated with increase DNA fragmentation in a dose-dependent manner, However PARP cleavage or bax expression was not detected. Our results suggest that Red-ginseng extract has dual effects, the cell proliferative or cytotoxic effect, on hNSCs in vitro with dose-dependent manner.

• Molecules and Cells
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• v.24 no.3
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• pp.424-430
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• 2007

The biological effects of low-dose radiation have been investigated and debated for more than a century, but its cellular effects and regulatory mechanisms remain poorly understood. This study shows the human cellular responses to low-dose radiation in CCD-18 Lu cells, which are derived from normal human lung fibroblasts. We examined a colony-forming assay for cell survival by ionizing radiation. Live cell counting and cell cycle analysis were measured for cell proliferation and cell cycle progression following low-dose irradiation. We examined Raf and Akt phosphorylation to determine the proliferation mechanism resulting from low-dose radiation. We also observed that p53 and p21 were related to cell cycle response. We found that 0.05 Gy of ionizing radiation enhanced cell proliferation and did not change the progression of the cell cycle. In addition, 0.05 Gy of ionizing radiation transiently activated Raf and Akt, but did not change phospho-p53, p53 and p21 in CCD-18 Lu cells. However, 2 Gy of ionizing radiation induced cell cycle arrest, phosphorylation of p53, and expression of p53 and p21. The phosphorylation of Raf and Akt proteins induced by 0.05 Gy of ionizing radiation was abolished by pre-treatment with an EGFR inhibitor, AG1478, or a PI3k inhibitor, LY294002. Cell proliferation stimulated by 0.05 Gy of ionizing radiation was blocked by the suppression of Raf and Akt phosphorylation with these inhibitors. These results suggest that 0.05 Gy of ionizing radiation stimulates cell proliferation through the transient activation of Raf and Akt in CCD-18 Lu cells.

• Molecules and Cells
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• v.42 no.7
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• pp.557-567
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• 2019

TSPAN12, a member of the tetraspanin family, has been highly connected with the pathogenesis of cancer. Its biological function, however, especially in ovarian cancer (OC), has not been well elucidated. In this study, The Cancer Genome Atlas (TCGA) dataset analysis revealed that upregulation of TSPAN12 gene expression was significantly correlated with patient survival, suggesting that TSPAN12 might be a potential prognostic marker for OC. Further exploration showed that TSPAN12 overexpression accelerated proliferation and colony formation of OVCAR3 and SKOV3 OC cells. Knockdown of TSPAN12 expression in A2780 and SKOV3 cells decreased both proliferation and colony formation. Western blot analysis showed that several cyclins and cyclin-dependent kinases (CDK) (e.g., Cyclin A2, Cyclin D1, Cyclin E2, CDK2, and CDK4) were significantly involved in the regulation of cell cycle downstream of TSPAN12. Moreover, TSPAN12 accelerated mitotic progression by controlling cell cycle. Thus, our data demonstrated that TSPAN12 could be a novel molecular target for the treatment of OC.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.329-332
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• 2002

We investigated the effect of Sarcodon aspratus extract on expression of cell cycle regulators. Methanol extract of Sarcodon aspratus showed a growth suppression on HepG2. As shown by western blot analysis, the expressions of cyclin A and Dl known as cell cycle regulators were decreased after treatment of Sarcodon aspratus extract. On the other hand, the expression of cyclin Bl was increased in the presence of Sarcodon aspratus extract. Furthermore, the expression of p53, a tumor supressor gene, and p27, a cell cycle dependent protein kinase inhibitor, were increased, whereas the expression of PCNA was decreased. In conclusion, our study suggests that growth inhibitory effect of Sardodon aspratus methanol extract on HepG2 is induced by cell cycle arrest in the Gl phase caused by decrease in cyclin A, Dl expressions and increases in p53, p27 expression.

• The Journal of Korean Medicine
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• v.23 no.2
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• pp.57-69
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• 2002

Objective: The aim of this study is to investigate the effect of Injin butanol fractions with Thin Layer Chromatography on Fas-mediated Apoptosis. Method: Injin-butanol fraction separated by TLC. MIT assay, cell cycle analysis, Caspase-3 protease assay, DNA fragmentation assay and quantitative RT-PCR were performed to evaluate the effects of TLC extraction of lnjin-butanol fraction on cell viability, cell cycle progression and apoptosis. Results: Scopoletin, luteolin, apigenin and unknown powder was isolated by TLC. Fas-mediated apoptosis analysis shows that scopoletin has inhibiting function on apoptosis. Caspase- 3 protease assay analysis shows that scopoletin inhibits activity of caspase-3. Quantitative RT-PCR analysis shows that no activity on caspase-3, but apoptosis inhibition cytokine -Bcl-2- is activated, and apoptosis activating cytokine -Bax- is unactivated. Conclusion: These results show that each fraction of Injin-butanol TLC extraction, especially scopoletin, acts as a protective function on liver cell viability, and inhibitory function on apoptosis. (J Korean Oriental Moo 2002;23(2):57-69)

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.3
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• pp.1043-1048
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• 2012

The COPS3 gene has stimulating effect on cell proliferation and progression of osteosarcomas and related cells. However, the features of COPS3 and its potential application as a therapeutic target in other cancers has not yet been studied. In this study, therefore, the effect of COPS3 silencing via COPS3 siRNA on lung cancer cell proliferation was examined. Expression levels of COPS3 gene in COPS3 siRNA infected cells and control siRNA infected cells were compared with real time PCR and Western blot analysis. Cell proliferation levels were comprehensively analyzed by MTT, BrdU incorporationy, and colony formation assays. For mechanistic assessment the effects of COPS3 silencing on cell cycle and apoptosis were analyzed using flow cytometry. Results showed that successful silencing of the COPS3 gene at both translational and transcriptional levels significantly reduced the proliferation and colony formation by lung cancer cells (p<0.01). Flow cytometry showed cell cycle arrest in the G0/G1 phase after COPS3 silencing, and more importantly, apoptosis was induced as a result of COPS3 knockdown, which negatively affected cell survival. Therefore, these results provide another piece of important evidence that the COPS3 gene expressed in lung cancer cells may play a critical role in stimulating proliferation. Down-regulation of COPS3 could significantly inhibit lung cancer cell growth, which was most likely mediated via induction of cell cycle arrest in G0/G1 phase and apoptosis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.42 no.6
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• pp.337-344
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• 2016

Objectives: The purpose of this study was to evaluate the anti-cancer activity of cisplatin by studying its effects on cell viability and identifying the mechanisms underlying the induction of cell cycle arrest and apoptosis on oral squamous cell carcinoma (OSCC) cell lines with varying p53 mutation status. Materials and Methods: Three OSCC cell lines, YD-8 (p53 point mutation), YD-9 (p53 wild type), and YD-38 (p53 deletion) were used. To determine the cytotoxic effect of cisplatin, MTS assay was performed. The cell cycle alteration and apoptosis were analyzed using flow cytometry. Western blot analysis was used to detect the expression of cell cycle alteration- or apoptosis-related proteins as well as p53. Results: Cisplatin showed a time- and dose-dependent anti-proliferative effect in all cell lines. Cisplatin induced G2/M cell accumulation in the three cell lines after treatment with 0.5 and $1.0{\mu}g/mL$ of cisplatin for 48 hours. The proportion of annexin V-FITC-stained cells increased following treatment with cisplatin. The apoptotic proportion was lower in the YD-38 cell line than in the YD-9 or YD-8 cell lines. Also, immunoblotting analysis indicated that p53 and p21 were detected only in YD-8 and YD-9 cell lines after cisplatin treatment. Conclusion: In this study, cisplatin showed anti-cancer effects via G2/M phase arrest and apoptosis, with some difference among OSCC cell lines. The mutation status of p53 might have influenced the difference observed among cell lines. Further studies on p53 mutation status are needed to understand the biological behavior and characteristics of OSCCs and to establish appropriate treatment.

• Environmental Mutagens and Carcinogens
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• v.24 no.3
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• pp.113-120
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• 2004

Chromium compounds are known human and animal carcinogens. In this study, the effects of sodium chromate on apoptosis and cell cycle were investigated in order to unveil the elements of early cellular responses to the metal. Using Chinese hamster ovary cells(CHO-K1-BH4), we found taht chromium (VI) treatment induced apoptosis in these cells, as signified by nuclear fragmentation, DNA laddering on agarose gel electrophoresis, and an increased proportionof cells with hypodiploid DNA. Preceding these changes, chromium (VI) treatment increased caspase 3 pritease activity and also increased expression of p53 protein, while the level of bcl2 protein was not changed. Coincubation with caspase inhibitor, Z-DEVD-FMK, inhibited chromium-induced apoptosis. In the flow cytometric analysis using propidium iodide fluorescence, an increase of cell population in G2/M phase was shown in cells exposed to at least 160 $\mu\textrm{m}$ of sodium chromate for 72h, form 9.8% for 0$\mu\textrm{m}$ chromium (VI) to 26.4% for 320$\mu\textrm{m}$ chromium(VI). Taken together, these findings suggest that chromium(VI)-induced apoptosis is accompanied by G2/M cell cycle arrest, and that p53-mediated pathway may be involved in positive regulation of G2/M arrest and a concurred apoptosis in CHO cells.