• Biomedical Science Letters
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• v.25 no.2
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• pp.196-200
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• 2019

Effect of retinoids, i.e., all-trans retinoic acid and 13-cis retinoic acid, on the activity of nitric oxide synthase (NOS) was evaluated in human malignant keratinocytes to examine the possible correlation of retinoids with NOS activities. All-trans retinoic acid and 13-cis retinoic acid did not alter the nitric oxide (NO) production. However, in the presence of lipopolysaccharide (LPS, $1{\mu}g/mL$), they significantly increased NO release in a dose-dependent manner until 48 h at concentrations of $50{\sim}100{\mu}M$. The degree of upregulation of NO by all-trans retinoic acid and 13-cis retinoic acid increased up to 35% and 37%, respectively, compared to that by the control, which demonstrated the upregulation of LPS-inducible nitric oxide synthase (iNOS)-dependent generation of NO as well as showing a crucial link between retinoids-induced activity and NOS. Findings of this study now suggest that the upregulation of LPS-iNOS activity may be associated with modulation of retinoids-induced control of cellular developmental processes, which may produce new therapeutics of retinoids in the complexity of how NO affects human keratinocytes.

• Biomedical Science Letters
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• v.24 no.1
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• pp.50-54
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• 2018

N-nitroso-N-methylurea (NMU) and N-nitroso-N-ethylurea (NEU), direct alkylating chemical mutagens and carcinogens, are shown to be the upregulators of cellular $NF-{\kappa}B$, regulating various genes that mediate tumorigenesis and carcinogenesis. Nitric oxide (NO), a toxic reactive radical gas, has been known to induce programmed cell death or apoptosis in various cells. Therefore, the assessment of NO production was examined to elucidate the possible contribution of NO release to the chemical carcinogenic potency of NMU and NEU in human skin cells. NMU and NEU did not alter the NO production, but they caused a significant downregulation of the NO generation on lipopolysaccharide (LPS)-induced NO production at concentrations ranging from $2{\sim}5{\mu}M$. The degree of downregulation of NO by NMU and NEU decreased up to 15% and 20%, respectively, compared to the control. These results demonstrate that the LPS-inducible keratinocytes NO synthase is involved in modulating carcinogenic potency by NMU and NEU, and the regulation of the cellular $NF-{\kappa}B$ activity by NMU and NEU is negatively correlated with the level of LPS-induced NO production in human skin cells. The findings of this study suggest the hypothesis that NMU and NEU-induced carcinogenesis may be associated with the downregulation of NO production, and the inducible NO may play an important role in NMU and NEU-induced carcinogenicity in human epidermal keratinocytes.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.20 no.3
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• pp.14-28
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• 2007

Objective : Hwagi-Jokyeong-Tang (化氣調經湯, HJT) was described in DongeuiBogam(東醫寶鑑). This remedy has been used to treat patients with Naryeok, which is similar as tuberculous cervical lymphadenitis in western medicine. Methods : In this study, the present author investigated the effects of HJT on on Human HaCaT keratinocyte and malignant melanoma cells such as SK-MEL-2 and B16F10 in terms of cell viabilities, proliferations, DPPH free radical scavenging activities, oxygen free radical productions and inhibitory action on elastase activities. Results : HJT acceleated proliferation of HaCaT keratinocytes dose-dependantly. HJT also prevented cell death of HaCaT induced by Hydrogen peroxide, which products oxygen free radicals. On the contrary, HJT did not affect proliferations of SK-MEL-2 or B16F10. In addition, HJT was shown to have DPPH free radical scavenging activities and also have inhibitory effects on elastase activities too. On the fluorescent examinations, the present author know that HJT did not affect production levels of oxygen free radicals in malignant melanoma cell, SK-MEL-2. Conclusions : These results suggest that HJT has possibilities of usage for functional cosmetics which have skin regeneration or prevention from skin tissue injury.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.20 no.3
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• pp.82-97
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• 2007

Objective : Cortex of Ulmi pumilae(CUP) has been used to treat several diseases including boil, swelling, and scabies etc. Recently, CUP was known to have wrinkle care and whitening actions. But, It's exact mechanisms are unclear. Methods : The present study was designed to investigate effects of CUP on Human HaCaT keratinocyte and malignant melanoma cells such as SK-MEL-2 and B16F10 in terms of cell viabilities, proliferations, DPPH free radical scavenging activities, oxygen free radical productions and inhibitory action on elastase activities. Results : CUP accelerated proliferation of HaCaT keratinocytes in the lower concentration. CUP also prevented cell death of HaCaT induced by Hydrogen peroxide, which products oxygen free radicals. On the contrary, CUP did not affect proliferations of SK-MEL-2 or B16F10. Futhermore, CUP showed inhibitory action against SK-MEL-2 proliferation at the concentration of $500{\mu}g/m{\ell}$ In addition, CUP was shown to have DPPH free radical scavenging activities and also have inhibitory effects on elastase activities too. On the fluorescent examinations, the present author knows that CUP elevated production levels of oxygen free radicals in malignant melanoma cell, SK-MEL-2. Conclusions : These results suggest that CUP has possibilities of usage for functional cosmetics which have wrinkle care and whitening activities and related mechanisms are involved in inhibition of elastase action and acceleration of oxidative stress in melanoma cell.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.3
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• pp.219-227
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• 2005

Purpose: Abnormalities in the p53 gene are regarded as the most consistent genetic abnormalities detected in head and neck squamous cell carcinogenesis. Two new members of the p53 gene family, p73 and p63 have recently been identified. They share considerable sequence homology with p53 in the transactivation, DNA binding, and oligomerization domains, indicating possible involvement in carcinogenesis. Disruption of the homeostatic balance between proliferation and apoptosis is widely believed to contribute to human oral carcinogenesis. The aim of this study was to analyze expression of p63 in squamous cell carcinogenesis and to compare with immunochemical markers representing cell proliferation and apoptosis. Materials and Methods: Using the Syrian hamster oral cancer model, the fraction of apoptotic (apoptotic index-AI), proliferating (mitotic index-MI) and p63 expressing keratinocytes were examined at normal, dysplastic and malignant oral epithelium using the TUNEL assay, PCNA and p63 immunostaining. Results: p63 significantly increased between normal and dysplastic epithelium and between dysplastic and malignant epithelium. PCNA significantly increased between normal and dysplastic epithelium and between normal and malignant epithelium. However, increase between dysplastic and malignant epithelium, though still increasing, was not statistically significant. The percentage of TUNEL positive cells increased from normal to dysplastic epithelium and returned to normal keratinocyte level in the malignant epithelium. However, differences between tissue types were not significant. The ratio of MI:AI increased significantly only in the dysplastic-malignant epithelial transition. The increase of p63 expression closely reflected the change in the MI:AI ratio during oral carcinogenesis. Conclusion: The p63 may be associated with the regulation of epithelial proliferation and apoptosis in DMBA-induced hamster buccal pouch squamous cell carcinogenesis. Further study is required to investigate which p63 isoforms are involved in hamster buccal pouch carcinogenesis.

• Nutritional Sciences
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• v.9 no.3
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• pp.212-226
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• 2006

The involvement of arachidonic acid (AA) metabolizing enzyme, lipoxygenase (LOX), in the development of particular tumors in humans has gradually been acknowledged and LOX has emerged as a novel target to prevent or treat human cancers. In the mouse skin carcinogenesis model, which provides an excellent model to study multistage nature of human cancer development, many studies have shown that some of the LOXs are constitutively upregulated in their expression. Moreover, application of LOX inhibitors effectively reduced tumor burdens, which implicates the involvement of LOX in mouse skin tumor development as well. 8S-LOX is a recently cloned LOX, which is specifically expressed in mouse skin after 12-O-tetradecanoyl-phorbol-13-acetate (TPA) treatment but not in normal skin. Unlike other members of the LOX 'family' expressed in mouse skin, this TPA-induced expression of 8S-LOX is prominent only in the skin of the TPA tumor promotion-sensitive strains of mice (SENCAR, CD-1, and NMRI) but not in the promotion-resistant C57BL/6J mice. This is a very unique phenomenon among strains of mice. Constitutive upregulation of 8S-LOX was also found in early stage papillomas and the expression was gradually reduced as the tumors became malignant. Based on these observations, it has been thought that 8S-LOX is involved in TPA-induced tumor promotion as well as in tumor conversion from papillomas to carcinomas. In accordance with this hypothesis, several studies have suggested possible roles of 8S-hydroxyeicosatetraenoic acid (HETE), an AA metabolite of 8S-LOX, in mouse skin tumor development. A clastogenic activity of 8S-HETE was demonstrated in primary keratinocytes and a close correlation between the levels of etheno-DNA adducts and 8S-HETE during skin carcinogenesis was also reported. On the other hand, it has been reported that 8S-LOX protein expression is restricted to a differentiated keratinocyte compartment Moreover, reported findings on the ability of 8S-HETE to cause keratinocyte differentiation appear to be contrary to the procarcinogenic features of the 8S-LOX expression, presenting a question as to the role of 8S-LOX during mouse skin carcinogenesis. In this review, molecular and biological features of 8S-LOX as well as current views on the functional role of 8S-LOX/8S-HETE during mouse skin carcinogenesis are presented.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.10
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• pp.1594-1600
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• 2004

Effects of mistletoe (Viscum album) extract and pueraria (Pueraria radix) extract on cellular NF-$textsc{k}$B activity were evaluated in human malignant keratinocytes (SCC-13) to elucidate the possible correlation of NF-$textsc{k}$B with antioxidant activity. The antioxidant activities of these natural extracts were examined in four different evaluation methods, i.e., lipid peroxidation value (POV) evaluation test, I,l-diphenyl-2-picrylhydrazyl radical (DPPH), nitric oxide (NO) scavenging test, and reducing power assay. Pueraria extract (0.5 mg) and mistletoe extract (5 mg) downregulated the cellular NF-$textsc{k}$B activation up to 35% and 10% compared to the control, respectively, although their effects were lower than the known NF-$textsc{k}$B downregulator, vitamin C (8.8 mg, 53%) in a cell-based NF-$textsc{k}$B activity assay system. In the POV test, relative antioxidant activities of mistletoe extract (86%) and pueraria extract (75%) were significantly higher than the known antioxidant, vitamin C (48%) at the same concentration (10 mg) and the degree of activity increased in a dose-dependent manner. Pueraria extract showed more potential radical scavenging activities than those of mistletoe extract evaluated in both DPPH and NO test. Especially, the NO radical scavenging activity of pueraria extract ($SC_{50}$/, 88 $\mu$g) was comparable to that of vitamin C ($SC_{50}$/, 77 $\mu$g). Even pueraria extract possessed a much less reducing power compared to vitamin C, it also revealed higher reducing power than that of mistletoe extract. These results indicate that mistletoe extract and pueraria extract may serve as an useful natural antioxidant agents, and led to suggest the hypothesis that compounds having an antioxidant activity, i.e., radical scavenging activity or reducing power may be correlated with the downregulation of NF-$textsc{k}$B activation in human keratinocytes.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.1037-1047
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• 2016

HOX transcription factors are evolutionarily conserved in many different species and are involved in important cellular processes such as morphogenesis, differentiation, and proliferation. They have also recently been implicated in carcinogenesis, but their precise role in cancer, especially in cervical cancer (CC), remains unclear. In this work, using microarray assays followed by the quantitative polymerase chain reaction (qPCR), we found that the expression of 25 HOX genes was downregulated in CC derived cell lines compared with non-tumorigenic keratinocytes. In particular, the expression of HOXA9 was observed as down-modulated in CC-derived cell lines. The expression of HOXA9 has not been previously reported in CC, or in normal keratinocytes of the cervix. We found that normal CC from women without cervical lesions express HOXA9; in contrast, CC cell lines and samples of biopsies from women with CC showed significantly diminished HOXA9 expression. Furthermore, we found that methylation at the first exon of HOXA9 could play an important role in modulating the expression of this gene. Exogenous restoration of HOXA9 expression in CC cell lines decreased cell proliferation and migration, and induced an epithelial-like phenotype. Interestingly, the silencing of human papilloma virus (HPV) E6 and E7 oncogenes induced expression of HOXA9. In conclusion, controlling HOXA9 expression appears to be a necessary step during CC development. Further studies are needed to delineate the role of HOXA9 during malignant progression and to afford more insights into the relationship between downmodulation of HOXA9 and viral HPV oncoprotein expression during cercical cancer development.

• Korean Journal of Pharmacognosy
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• v.35 no.1 s.136
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• pp.92-97
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• 2004

Effect of AGI $({\alpha}-Glucosidase\;Inhibitor)-1120$, pine (Pinus densiflora) bark extract and Chaga mushroom (Inonotus obliquus) - and Chaga mushroom mycelium extracts on cellular $NF-{\kappa}B$ activation in malignant human keratinocytes (SCC-13) were evaluated to elucidate the possible correlation of $NF-{\kappa}B$ with antioxidant activity. The antioxidant activities of these natural products were examined in three different evaluation methods, i.e., lipid peroxidation value (POV) evaluation test, and 1,1diphenyl-2-picrylhydrazyl radical (DPPH) and nitric oxide (NO) scavenging test. In a cell-based $NF-{\kappa}B$ monitoring assay systern, all samples revealed the downregulatory profiles on the cellular $NF-{\kappa}B$ activity. AGI -1120 (1, 2 mg) and Chaga mushroom extract (0.05, 0.1 mg) downregulated the $NF-{\kappa}B$ activity in a dose-dependent manner. Chaga mushroom mycelium extract (5 mg) significantly inhibited the $NF-{\kappa}B$ activity (p<0.05). Although AGI-1120 and Chaga mushroom mycelium extract exhibited no antioxidant activities evaluated in pay, Chaga mushroom extract showed antioxidant in a dose-dependent manner at concentrations of $0.05{\sim}1$ mg. While AGI-1120 and Chaga mushroom extract possessed a relatively potential DPPH radical scavenging activity, the NO scavenging activity of Chaga mushroom extract $(SC_{50}:47\;{mu}g)$ was higher than the known antioxidant, vitamin C $(SC_{50}:77\;{mu}g)$. These results suggest that AGI-1120 and Chaga mushroom- and Chaga mushroom mycelium extracts may serve as an useful radical scavenging antioxidant agents with $NF-{\kappa}B$ inhibitory effect in human skin.