• Journal of Life Science
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• v.15 no.5 s.72
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• pp.726-733
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• 2005

Histone deacetylase (HDAC) inhibitors target key steps of tumor development. They inhibit proliferation, induce differentiation and/or apoptotic cell death, and exhibit potent antimetastatic and antiangiogenic properties in cancer cells in vitro and in vivo. Although they are emerging as a promising new treatment strategy in malignancy, how they exert their effect on human non-small cell lung cancer cells is as yet unclear. The present study was undertaken to investiate the underlying mechanism of a HDAC inhibitor trichostatin A (TSA)-induced growth arrest and its effect on the cell cycle control gene products in a human lung carcinoma cell line A549. TSA treaoent induced the growth inhibition and morphological changes in a concentration-dependent manner. Treatment of A549 cells with TSA resulted in a concentration-dependent increased G1 (under 100 ng/ml) and/or G2/M (200 ng/ml) cell population of the cell cycle as determined by flow cytometry Moreover, 200 ng/ml TSA treatment significantly induced the population of sub-G1 cells (23.0 fold of control). This anti-proliferative effect of TSA was accompanied by a marked inhibition of cyclins, positive regulators of cell cycle progression, and cyclin-dependent kinases (Cdks) expression and concomitant induction of tumor suppressor p53 and Cdk inhibitors such as p21 and p27 Although further studies are needed, these findings provide important insights into the possible molecular mechanisms of the anti-cancer activity of TSA in human lung carcinoma cells.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.2
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• pp.187-193
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• 2011

Neurofibromatosis is known as an autosomal dominant disorder caused by a mutation of a tumor suppressor gene on the long arm of chromosome 17 that affects the bone, nervous system, soft tissue, skin, and endocrine system. The most characteristic finding, which is helpful for clinical diagnosis as well, is the neurofibroma. Likewise brown macules called Cafe-au-lait spots with color of caffee latte, and Lisch nodules found around iris are useful to diagnose the disease. As known, the possibility of the neurofibromatosis occurred in oral cavity is relatively rare, and in most of cases it is related to soft tissue changes with single or multiple neurofibromatosis. The purpose of this report is to present characteristic dental findings which were found in a 4-year-old male and his father, both diagnosed as neurofibromatosis at Chonbuk National University Hospital before visiting our department, pediatric dentistry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.1
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• pp.8-16
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• 2013

We investigated the effect of red cabbage extract (RCE) on cell death in MDA-MB-231 human breast cancer cells. Cells were cultured in the presence 1.0, 1.5, and 2.0 mg/mL concentrations of RCE for 24 hours. MTT assays demonstrated that mitochondrial dehydrogenase activities decreased in a dose-dependent manner in cells (p<0.05). In contrast, the proportion of dual staining with Hoechst 33342/ethidium bromide (EtBr) for cell death increased in a dose-dependent manner in cells (p<0.05). Flow cytometry assays revealed that cell death caused by an apoptotic program increased in a dose-dependent (p<0.05). Also, increased ROS accumulation in cells, as revealed by DCF-DA staining, was observed in a dose-dependent fashion (p<0.05). The apoptosis suppressor gene Bcl-2 decreased significantly at the mRNA level. Pro-apoptotic genes Bax and caspase-3, genes that are related to the last stage of apoptosis significantly increased. The Bcl-2/Bax ratio which is an important indicator of apoptosis, was found to have significantly decreased dose dependence. These results taken together indicate that the effect of red cabbage extract induces cell death in MDA-MB-231 human breast cancer cells.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2699-2705
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• 2014

This study was to undertaken to investigate the impacts of AhR, CYP1A1, GSTM1 genetic polymorphisms on the R273G mutation in exon 8 of the tumor suppressor p53 gene (TP53) among polycyclic aromatic hydrocarbons (PAHs) exposed to coke-oven workers. One hundred thirteen workers exposed to PAH and 82 control workers were recruited. We genotyped for polymorphisms in the AhR, CYP1A1, GSTM1, and TP53 R273G mutation in blood by PCR methods, and determined the levels of 1-hydroxypyrene as PAH exposure marker in urine using the high pressure liquid chromatography assay. We found that the distribution of alcohol users and the urinary excretion of 1-OHP in the exposed workers were significantly higher than that of the control workers (p=0.004, p<0.001, respectively). Significant differences were observed in the p53 genotype distributions of smoking subjects (p=0.01, 95%CI: 1.23-6.01) and PAH exposure (p=0.008, 95%CI: 1.24-4.48), respectively. Further, significant differences were observed in the p53 exon 8 mutations for the genetic polymorphisms of Lys/Arg for AhR (p=0.02, 95%CI: 0.70-15.86), Val/Val for CYP1A1 (p=0.04, 95%CI: 0.98-19.09) and null for GSTM1 (p=0.02, 95%CI: 1.19-6.26), respectively. Our findings indicated that polymorphisms of PAH metabolic genes, such as AhR, CYP1A1, GSTM1 polymorphisms may interact with p53 genetic variants and may contribute to PAH related cancers.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7675-7679
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• 2013

Background: A missense mutation in exon 7 (R249S) of the p53 tumor suppressor gene is characteristic of aflatoxin B1 (AFB1) exposure. AFB1 is believed to have a synergistic effect on hepatitis virus B (HBV) carcinogenesis. However, results of studies comparing R249S prevalence among patients are conflicting. The aim of this study was to determine the prevalence of the R249S mutation in hepatocellular carcinoma (HCC) patients with or without positive HBsAg. Materials and Methods: Paraffin embedded liver tissues were obtained from 124 HCC patients who underwent liver resection and liver biopsy in King Chulalongkorn Memorial Hospital. Restriction fragment length polymorphism (RFLP) was utilized to detect the R249S mutation. Positive results were confirmed by direct sequencing. Results: Sixty four (52%) patients were positive for HBsAg and 18 (15%) were anti-HCV positive. 12 specimens tested positive by RFLP. Ten HCC patients (8.1%) were confirmed to be R249S positive by Sanger sequencing (AGG to AGT). Out of these 10, six were HBsAg positive, and out of the remaining 4, two were anti-HCV positive. The R249S prevalence among HCC patients with positive HBsAg was 9.4% compared to 6.7% for HBsAg negative samples. Patients with the R249S mutation were younger ($55{\pm}10$ vs $60{\pm}13$ year-old) and tended to have a more advanced Edmonson-Steiner grade of HCC, although differences did not reach statistical significance. Conclusions: Our study shows moderate prevalence of aflatoxin B1-related p53 mutation (R249S) in HCC with or without HBsAg. HBsAg positive status was not associated with R249S prevalence.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9313-9317
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• 2014

Fragile histidine triad (FHIT) is a suppressor gene related to cervical cancer through CpG island hypermethylation. Folate is a water-soluble B-vitamin and an important cofactor in one-carbon metabolism. It may play an essential role in cervical lesions through effects on DNA methylation. The purpose of this study was to observe effects of folate and FHIT methylation and HPV 16 on cervical cancer progression. In this study, DNA methylation of FHIT, serum folate level and HPV16 status were measured using methylation-specific polymerase chain reaction (MSP), radioimmunoassay (RIA) and polymerase chain reaction (PCR), respectively, in 310 women with a diagnosis of normal cervix (NC, n=109), cervical intraepithelial neoplasia (CIN, n=101) and squamous cell carcinoma of the cervix (SCC, n=101). There were significant differences in HPV16 status (${\chi}^2=36.64$, P<0.001), CpG island methylation of FHIT (${\chi}^2=71.31$, P<0.001) and serum folate level (F=4.57, P=0.011) across the cervical histologic groups. Interaction analysis showed that the ORs only with FHIT methylation (OR=11.47) or only with HPV 16 positive (OR=4.63) or with serum folate level lower than 3.19ng/ml (OR=1.68) in SCC group were all higher than the control status of HPV 16 negative and FHIT unmethylation and serum folate level more than 3.19ng/ml (OR=1). The ORs only with HPV 16 positive (OR=2.58) or with serum folate level lower than 3.19ng/ml (OR=1.28) in CIN group were all higher than the control status, but the OR only with FHIT methylation (OR=0.53) in CIN group was lower than the control status. HPV 16 positivity was associated with a 7.60-fold increased risk of SCC with folate deficiency and with a 1.84-fold increased risk of CIN. The patients with FHIT methylation and folate deficiency or with FHIT methylation and HPV 16 positive were SCC or CIN, and the patients with HPV 16 positive and FHIT methylation and folate deficiency were all SCC. In conclusion, HPV 16 infection, FHIT methylation and folate deficiency might promote cervical cancer progression. This suggests that FHIT may be an effective target for prevention and treatment of cervical cancer.

• Journal of Gastric Cancer
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• v.4 no.3
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• pp.169-175
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• 2004

Purpose: The tumor suppressor gene p53 has been shown to be a factor in the carcinogenesis or progression of gastric cancer. The mutant p53 has been reported to cause a higher risk of lymph-node metastasis. Futhermore, mutation of the p53 has been linked to a poor prognosis for gastric cancer. The heat shock protein-27 (HSP27), a stress protein, has also been reported to be a poor prognostic factor in ovarian and breast cancers. However, in gastric-cancer patients, controversies exist as to its influence on the prognosis. In the present study, we used an immunohistochemical stain to observe the effects of p53 and HSP27 on the clinicopathological factors and on the prognosis for gastric-cancer patients. Materials and Methods: To evaluate the significance of p53 and HSP27 in gastric cancer patients, we analyzed 212 cases of gastric cancer (stage I.IV). Tissue samples of 212 patients were stained immunohistochemically for the mutant p53 protein and for HSP27. The correlations between protein expression and the clinicopathological factors were investigated. Results: The overall expression rates for p53 and HSP27 were $36.9\%\;and\;27.8\%$, respectively. p53 and HSP27 were correlated to each other because the HSP27 expression rate was higher in the p53-positive group (P=0.046). Statistically, the p53 and the HSP27 expression rates were significantly increased in the case of tumor invasiveness, lymphatic metastasis and vessel involvement. Therefore, they play a role in cancer progression. The 5-year survival rates of the p53-positive and the p53-negative groups were $62.8\%\;and\;60.1\%$, respectively (P=0.793) while the 5-year survival rates for the HSP27-positive and HSP27-negative groups were $54.2\%\;and\;63.1\%$, respectively (P=0.090). Conclusion: p53 and HSP27 were correlated to each other in our immunohistochemical study of gastric carcinomas and they were not independent prognostic factors in gastric- cancer patients. However, further studies are needed to determine their prognostic values for gastric-cancer patients.

• Tuberculosis and Respiratory Diseases
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• v.48 no.5
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• pp.682-698
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• 2000

Glucocorticoid receptor (GR) functions as a suppressor of inflammation by inhibiting the expression of many cytokine genes activated by NF-${\kappa}B$. The goal of this study is to investigate the mechanism by which GR repress NF-${\kappa}B$ activation in lung epithelial cells. We used A549 and BEAS-2B lung epithelia! cell lines. Using Ig$G{\kappa}$-NF-${\kappa}B$ luciferase reporter gene construct, we found that dexamethasone significantly suppressed TNF-$\alpha$-induced NF-${\kappa}B$ activation and the overexpression of GR showed dose-dependent reduction of TNF-$\alpha$-induced NF-${\kappa}B$ activity in both cell lines. However, DNA binding of NF-${\kappa}B$ induced by TNF-$\alpha$ in electromobility shift assay was not inhibited by dexamethasone. Super shift assay with anti-p65 antibody demonstrated the existence of p65 in NF-${\kappa}B$ complex induced by $\alpha$ Western blot showed that $I{\kappa}B{\alpha}$ degradation induced by TNF-$\alpha$ was not affected by dexamethasone and $I{\kappa}B{\kappa}$ was not induced by dexamethasone, neither. To evaluate p65 specific transactivation, we adopted co-transfection study of Gal4-p65TA1 or TA2 fusion protein expression system together with 5xGal4-luciferase vector. Co-transfection of GR with Gal4-p65TA1 or TA2 repressed luciferase activity profoundly to the level of 10-20% of p65TA1- or TA2-induced transcriptional activity. And this transrepressional effect was abolished by co-transfection of CBP of SRC-1 expression vectors. These results suggest that GR-mediated transrepression of NF-${\kappa}B$ in lung epithelial cells is through competing for binding to limiting amounts of transcriptional coactivators, CBP or SRC-1.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.6 no.1
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• pp.67-79
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• 2000

Objective : Hedyotis diffusa has been used as an anticancer agent for several decades in oriental medicine. We test whether the methanol extract of the herb affects transcriptional activation factors including $NF-{\kappa}B$ and AP-1. Methods : 1. HL-60 cells were treated with various concentrations(from 200 to $50{\mu}g/ml$) of methanol extract and $H_2O$ extract($200{\mu}g/ml$)of hedyotis diffusa, After 48h later, the cells were tested for viability by MTT assay. 2. The HL-60 cells were treated with $200{\mu}g/ml$ of methanol extract for the indicated periods. First. Nuclear extracts were isolated and incubated with oligonucleotide probe of $NF-{\kappa}B$ and AP-1. Second. Nuclear extracts were isolated and reacted with p50, p65. c-rel pan-Jun, c-Jun, JunB. JunD antibody on ice for 30min. Finally The cell lysates were prepared and analyzed by western blotting using anti-Fas, anti-FasL and anti-p53 antibody. Results : 1. The methanol extract decreases the viability of human lymphoid origin leukemia HL-60 cells in a dose-dependent manner. 2. $NF-{\kappa}B$ is rapidly activated by the addition of the methanol extract, reaches a peak at 30min and gradually returns to resting level. We confirm that $NF-{\kappa}B$ is a heterodimer mainly composed of p65 subunit with c-Rel. 3. Transcriptional activation of AP-1 is detected at 30min and reaches a maximum at 1hr after stimulation of the cells with the methanol extract. AP-1 is mainly composed with Jur-D and partially Jug-B proteins. 4. the methanol extract of Hedyotis diffusa induces the expression of Fas, Fas ligand and p53 proteins of HL-60 cells in a time dependent fashion. Conclusions : These results suggest that the methanol extract of Hedyotis diffusa exerts anticancer effects to induce the death of human leukomic HL-60 cells via activation of trascriptional factors such as $NF-{\kappa}B$ and AP-1, increase in expression of Fas mediated signalling proteins, and induction of tumor suppressor gene. p53.

• Journal of Life Science
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• v.30 no.10
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• pp.867-876
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• 2020

This study investigated the repair of UVB-induced cell damage by magnolol. We performed a drug-repurposing screen, and, in the STAT3 reporter gene assay, magnolol was identified as a suppressor of STAT3 that improves the cell viability of HDF cells. HDF cells treated with IL-6, UVB, and IFNγ showed the highest expression of Jak2 and phosphorylated STAT3 (p-STAT3), and magnolol was able to decrease the expression of Jak2 and p-STAT3 in UVB-induced cells. Moreover, UVB-damaged cell growth increased significantly in correlation with both reactivation and with magnolol in a dose-dependent manner. Compared with AG490 (a Jak2 inhibitor) treatment of UVB-treated HDF cells, cell proliferation increased significantly. We confirmed that AG490 and magnolol reduced TNF-α concentrations, and Western blotting (protein level) showed decreases in Jak2 and p-STAT3 expression in only the magnolol-treated cells. The expression of Jak2, p-STAT3, and SOCS3 also increased only after treatment with magnolol. Cells were treated with magnolol and ML385 (an NRF2 inhibitor), and these secondary metabolites reduced cell proliferation and NRF2 expression. The amount of MMP9 was also increased by cotreatment with magnolol and ML385. Collectively, these results demonstrate the potential of magnolol for repairing cells after UVB-induced damage by regulating the expression of NRF2, SOCS3, Jak2, and STAT3.