We studi ed the difTerential elTect of vitamins A, C, U. and E on normal human 이 al keratinocyte(NHOK) , HPV-16 E6E7 immor talized human oral keratinocyte(1HOK) , Oncogene transfected HPV-16 immortalized ce1ls(OTOK) , and two ol'al sq ua mous cell line(HNSCC30‘ HNSCC31) according to carcinogenesis stage. The vitamin effect was evaluated by morphology. ce ll viabi lity. a nd orgnaotypic culture Vitamin A has a greater negative effect on growth for all NHOK IHOK HNSCC. es pec ially N-Ras t rans fected IHOK, Vitamin D & E revealed no significant cell activity on NHOK lHOK, ad OTOK Vitamin C was found increased cell viability to IHOK and OTOK 1n primary oral squmaous cell ca rcino ma (HN30 ). vitam in 0 and C showing increased cell growth , but vitamin E showing no effect 1n metastatic oral squamous cell ca rcinoma(HN31), vitamin C has prol iferative effect , but vitamin 0 & E has anti-proliferative effect Vitamin A t reated normal a nd ma lignant ce1ls by organotypic cu lt ure. showed reduction of epithelial layer and in vasion to connective tissue. , especia lly in 1HOK & oncogene-transfected 1HOK, 1n conclusion. three-dimensional culture sys tem may be useful as a model to acess the efficiency of agents such as a1l trans retinoic acid can preventing progression of these premaligant lesion to maligant oral carcinoma(ch emopreventive agent) .

Studies to evaluate distribution of markers in normal keratinocyte and their immortalized keratinocyte are appropriate to evaluate the normal and preneoplastic lesion of oral cancers as biochemical and cytochemical changes associate with tumorigenesis being not completely understood. Complementary DNA microarray containing 6000 sequence -verified cDNA elements was used to systematically characterize the variation in gene expression patterns of NHOK cells vs. immortalized keratinocyte by HPV16 E6-E7(IHOK). Examination of gene expression that is 85 clones cDNAs exhibits greater than 2 fold overexpression in NHOK probes relative to IHOK probe, 147 cDNAs reveal greater 2 fold overexpression in IHOK relative to NHOK probe.The high similarity in gene expression (96.5%) between IHOK and NHOK cells suggests that only an additional 232/6720 (3.5%) of the genome is differentially gene activated during HPV16 immoratlized keratinocyte growth and differentiation. Examination of gene expression that differs between NHOK and IHOK cellsapprear to be related to : cell adhesion & recognition, cell cycle regulator, apoptosis, transciption factors, growth factors and therir receptors, cytoskeletal and extracellular matrix proteins, signal transduction modulators and effectors, and miscellaneous. The gene expression of cell recognition factor such as endothelin 1, collagen IV, fibronectin, and SPR1 in IHOK were upregulated. Distinct or duplicated cDNA clones representing the same gene were typically clustered in adjacent rows in the clustered gene map. Therefore the differentially expressed and identified genes should be informative in studying oral epithelial cell carcinogenesis and such studies should foster the research of molecular markers allowing to assess the phenotypeof malignant epithelial tumor.

Nitric oxide (NO) has been known to inf1uence cell fate through apoptotic or necrotic cell death. Here, we investigated the role of nitric oxide on the growth and viability of immortalized human salivary gland (HSG) cells 띠 vitro. Treatrnent of HSG with a NO donor, S-nitroso-N-acetyl-DL-penκi1lamine (SNAP), significantly diminished the growth rate of HSG in a concentration dependent manner. However, this retardation of cell비ar growth rate was not corresponded to the apoptotic cell death of HSG cells, because there were no characteristic apopto디c features such as condensation of nuclear chromatin, nuclear fragmentation, and the apoptotic peak of propidium iodide (PI)-stained nuclei by flow cytome띠. 까ùs implies that HSG cells are resistant to NO-mediated 다π。to:잉city. 1n SNAP treated HSG cells, cell cycle analysis revealed that the number of G2/M phase increased markedly, according to while the percentage of cells in GO/Gl and S phases was not significantly affected. Otherwise, high concentrations of SNAP increased both P1 and annexin V positive cells. 1nterestingly, preincubation of HSG cells with iron chelator, deferoxamine (DFO), significantly diminished NO cytotoxicity more than when HSG cells are only incubated with SNAP which su잃.ests the role of iron homeostasis in NO-mediated cell death of HSG cells. 1n addi디。n ， treatrnent of HSG cells with SNAP specifically cleaved iron regulatory protein-2 (IRP2) while not affecting 1RP1. Collectively, the mπent results s멍gest that NO has a potential to control HSG cell growth through cell cycle arresting at G2/M phase. 1n addi디on ， intracellular iron homeostasis nùght play an important role in regulating cell survival of HSG cells

Soybean [Glycine max (L.) Merr.] is a major agricultural crop widely used for providing human and animal food owing to its high protein and oil content. For this reason, they have been consumed in Asia and world greatly and demand is ever increasing. Soybean is classified as a moderately salt-sensitive crop and its production is greatly affected due to increasing salinity stress. About 8 % of the world’s total land is salt-affected. In Korea, around 9 % of total agricultural land (approximately 130,000ha) was reclaimed since 1960's. In order to meet the demand for soybean and to solve arable land shortage problem, it is unavoidable to cultivate soybean in salt-affected soils. Fortunately, soybean germplasm has been shown to have salt-tolerant phenotypes, which have been used to identify the salt-tolerant genes. GmCHX1, a novel ion transporter, is one of the genes known to confer salt tolerance in soybeans. Present study was conducted to understand the effects of sequence variations of GmCHX1, on salt tolerance in wild and cultivated soybeans. A total of 1026 (301 lines of G. max and 725 lines of G. soja) lines were phenotyped for salt tolerance in greenhouse conditions. At the V1-V2 growth stage, the plants were treated with 100mM NaCl solution for two weeks and thereafter the response was measured depending on leaf scorch score (1-health, 3-mid, 5-dead). About 20 lines found to show tolerance to saline conditions and were selected for sequence analysis of GmCHX1. Most of the haplotypes detected in this study corresponded with the haplotype patterns in previous studies. However, several lines showed different patterns of polymorphism in the coding region, suggesting that sequencing of more lines and analysis for the polymorphism in GmCHX1 is needed in order to identify new haplotypes that could confer greater salt tolerance.