Oral malignant melanoma of the oral cavity is rare. Although the Asian population has a relatively high incidence of oral malignant melanoma in contrast to Caucasians, the clinical information in Korean has been rarely known. In addition, the clinical and histological classification of oral malignant melanoma has not been established up to now. So we investigated 26 cases of oral malignant melanomas on the basis of clinicopathological and immunohistochemical findings and reclassified the clinical and histological type. The results of this study are as followed. Oral malignant melanomas occurred at any age from 28 years to 73 years and their mean age was 58.6 years. Of 26 cases, 14 occurred in male and 12 in female. Oral malignant melanomas occurred almost in palate and/or maxillary gingiva (25 cases; 96.2%). Only one case occurred in mandibular gigiva. Oral malignant melanomas were clinically divided into macular(9 cases) and nodular type(17 cases), showing that the nodular type occurred more frequently. Oral malignant melanomas were histologically divided into in situ spreading(5 cases), invasive(13 cases), and combined type(8 cases), showing that the invasive type occurred most frequently. All cases showed positivity for S-100 and 15 cases(57.7%) for HMB-45 in immunohistochemical analysis. It was thought these results could provide basic data for the research on oral malignant melanoma in Korean and additional prospective and retrospective studies would be needed in order to find the relations with the prognosis of the patients
The major component of green tea is (-)-epigallocatechin-3-gallate(EGCG) which accounts for 5080% of catechin, representing 200300 mg in a brewed cup of green tea. EGCG has been known to possess growth inhibitory and pro-apoptotic effect on human cancer cell lines such as prostate, bladder and breast cancers. In contrast, several studies have suggested that EGCG could promote cell proliferation and/or survival instead of pro-apoptotic effect. Understanding how intracellular signaling pathways respond to EGCG may provide a clue to the difference of cell responses and basis for usefulness of EGCG as a chemopreventive and/or chemotherapeutic agent. To better understand the mechanisms responsible for the chemopreventive efficacy of EGCG, the authors tried to identify the key molecules that contributes to Akt activation and can inhibit this activation. In the present study, EGCG increased Akt phosphorylation, an activeform of Akt and negatively affect on direct upstream molecules of Akt including PTEN and EGFR, though Akt phosphorylation was increased.
To investigate the differential expression of genes by 635nm LEDs irradiation in arachidonic acid-treated human gingival fibroblasts, cDNA microarray was carried out. Human gingival fibroblasts were primary cultured and arachidonic acid was treated to induce inflammation. 635nm of wave length was used for LEDs irradiation. The experimental group was categorized into four group ; control, only LEDs irradiation group, only arachidonic acid-treated group and arachidonic acid-treated with LEDs irradiation group. The expression of 8,078 genes were increased and the expression of 7,103 genes were decreased in only LEDs irradiation group. For arachidonic acid-treated with LEDs irradiation group, the expression of 6,815 genes were increased, while the expression of 8,031 genes were decreased comparing with only arachidonic acid-treated group. IL-13alpha2 receptor was the most expressed gene in LEDs irradiation group comparing with control, followed by MMP3. Genes which the most down regulated was BIRC3 in LEDs irradiation group. PLAB genes was the most up-regulated in arachidonic acid treated with LEDs irradation group, followed by ranked RARRES1. Considering the classification by cell function, genes associated with signal transduction were the most affected by LEDs irradiation, followed by the genes associated with nucleoside, nucleotide and nucleic acid metabolism. In arachidonic acid treated with LEDs irradiation, genes associated with signal transduction and protein metabolism were affected. Taken together, LEDs irradiation could affect various biological process and could identify many genes related to LEDs irradiation, which could be used for clinical application.
The prominent side effect of cyclosporin A, immunosuppressive agent, in oral tissues is gingival overgrowth(GO). It is characterized by the gingival enlargement with epithelial thickening, a large number of proliferating fibroblasts and overproduction of ECM components. Fibroblast accumulation in Cs A induced GO is caused by the Inhibition of apoptosis. But CsA effect on normal human oral keratinocyte(NHOK) remains unclear. Transglutaminase 2(TGase 2) which is expressed and activated in tissue where epithelial cells undergo apoptosis has been used as a marker for apoptotic cells. The purpose of this study were to study the effect of CsA on the proliferation and apoptosis of cultured NHOK by TGase 2 expression. After primary cultured NHOK was treated by 0.1, 1.0 and 10ug/ml Cs A, growth curve, MTT assay for succinyl dehydrogenase activity and RT-PCR for TGase 2 mRNA expression were done. The obtained results were as follows. MTT assay showed about 65% cell viability at 1.0μg/ml and 40% at 10μg/ml CsA. Growth curve showed normal S curve on control & DMSO, while decreased growth rate after 3 days of higher CsA tx. TGase 2 mRNA expression of cultured NHOK was the highest at 10μg/ml Cs A. TEM showed chromosome margination, and vacuole formation and clustered mitochodria in cytoplasm of cultured NHOK after CsA tx. It suggested that higher CsA might induce apoptosis of NHOK correlated with increased TGase 2 mRNA expression
Low energy photon irradiation by light in the far red to near infrared spectral range(630~1000nm) using low energy lasers or light emitting diode arrays has been found to modulate various biological processes in cell culture and animal models. The purpose of this study was to examine the light emitting diode irradiation effect on activity of normal human osteoblast on titanium plate in vitro by various energy density, and to observe morphologic change of NHost on titanium plate and to analysis concentration of Ca++, IP and ALP. NHost were cultured in DMEM containing 10% FBS, and observed by inverted microscope for attatchment to the surface of titanium plate. Ca++, I.P., and alkaline phosphatase( ALP) concentration in medium was calculated during 4 weeks, which was treated with Wilcoxon rank, Anova test and linear regression. Morphologic changes showed LED produced in vitro increases of cell growth of 144~256% in NHost. During a culture period, Ca++ concentration was decreased. LED treatment(>3J/cm2) stimulate calcium consumption in NHost. Statistically, a significant difference was not found between LED power density. LED treated group(>3J/cm2) had higher total inorganic phosphate concentrations than control group in NHost. Statistically, a significant difference was not found between LED power density. No significant changes were observed between ALP acitivity and LED treatment. In spite of LED power density, there were rapid growth rate of NHost and no significant of Ca++, IP and P concentration but these concentration showed predominant change than that of control.
Intracellular pathogens must maintain redox homeostasis against the antimicrobial actions of reactive oxygen and nitrogen species produced by host cells. This study proves that glutathione is required to promote survival of an enteric pathogen Salmonella under the conditions producing reactive oxygen or nitrogen species. Glutathione is the non-protein thiol compound distributed in a variety of organisms and possesses strong electron-donating capability to reduce intracellular redox environment. To examine the role of glutathione on Salmonella redox homeostasis under oxidative and nitrosative stress conditions, gshB gene encoding glutathione synthetase was mutated by the one-step PCR inactivation method. The growth of gshB mutant Salmonella producing virtually no glutathione was greatly impaired in the culture media containing either hydrogen peroxide or nitric oxide donors. The results suggest that physiological levels of glutathione can provide a fundamental capability to maintain redox homeostasis for Salmonella in surviving oxidizing conditions of host cells.