"In recent days, there is much interest in the biocidal activity of silver since silver is known to be safe and effective as disinfectant and biocidal material against bacteria and viruses. There is also increased interest in the nano-sized silver particles which can be used as effective bactericidal material. The purposes of this study were to investigate the effect of silverized elastomers on growth of oral pathogenic microorganisms, including Streptococcus mutans, Fusobacterium nucleatum, Porphyromonas gingivalis by comparing with conventional non-silverized elastomers. The antibacterial efficacy of silverized elastomer against oral pathogenic microbes was investigated by modified disk diffusion test and growth inhibition test. In modified disk diffusion test, silverized elastomer showed no antibacterial activity against S. mutans, F. nucleatum and P. gingivalis, In culture medium, the growth of S. mutans, F. nucleatum, P. gingivalis was not inhibited by silverized elastomer. Silverized elastomer exhibited no bacteriostatic and/or bacteriocidal effects against some experimental strain."

"Metastasis consists of complex cascades and a lot of factors are involved in each step of metastasis. In recent studies, the role of epithelial-mesenchymal transition (EMT) in metastasis is suggested. EMT has a feature of epithelial cells conversing into mesenchymal cells morphologically and phenotypically, is a characteristic of malignant and metastatic cells in most cancer. The mesenchymal cells usually show more malignant phenotype, including invasion and metastasis. EMT can play an important role in metastasis of oral squamous cell carcinoma (OSCC). Although the role of Snail, slug, other transcriptional factors and E-cadherin are well known in human cancers, there are a few studies on N-cadherin and Twist expression in OSCC. The present study was aimed to analyze the expression of N-cadherin and Twist protein in OSCC from Korean patients. The immunohistochemical stain was performed using 58 primary OSCCs and 6 metastatic OSCCs, and the correlation between the expression of these proteins and clinicopathological parameters of OSCC patients was analyzed.The expression rate of high expression of N-cadherin was observed in 70.4% and Twist in 87.3% of OSCC. The expression of N-cadherin in metastatic OSCC increased than in corresponding primary OSCC (p<0.05). The spearman correlation coefficiency between N-cadherin and Twist was calculated as 0.228. The clinical factors such as lymph node metastasis and survival showed statistically significant correlation between N-cadherin expression. The expression of Twist was correlated with recurrence. In conclusion, the authors suggest that N-cadherin may play an important role in malignant behaviour of OSCC and can be considered as prognostic indicator of OSCC."

"Oral lichen planus (OLP) is an atypically keratinized and ulcerative lesion, producing severe pain and discomforts in the involved patients. Nevertheless, the etiological factor or the pathogenetic mechanism has not been clearly elucidated. In the present study, the different gene expressions were screened in 21 cases of OLP by immunohistochemical (IHC) array method using 80 antibodies, and found that the pathway of E-cadherin/β-catenin was abnormally expressed compared to the other essential genetic pathways. Particularly, the expressions of eIF5A, DHS, and DOHH, which are the biomarkers of protein translation, were remarkably reduced, nevertheless the expression of β-catenin was strongly positive in the 7 cases among 21 cases of OLP. The other expressions of p53, BCL-2, MDM-2, PAKT, BAX, BAK, BAD, NFkB, HO-1, etc, were usually weak or sparse, while the expressions of PCNA, CDK4, and HSP-70 were markedly increased. Taken together, it is presumed that the overexpression of β-catenin indicates the derangement of E-cad/β-catenin/NFkB pathway, causing the transcription of cellular proliferating genes in downstream events, i.e., PCNA and CDK4, and that it may be eventually relevant to the malignant potential of OLP epithelial cells. It is also suggested that the activation of β-catenin/TCF/LEF1 pathway be closely relevant to the immunological reaction of OLP with the accumulation of T-cells underneath the mucosal epithelium. "

"Oral squamous cell carcinoma (OSCC) develops through multistep process, that is, from normal mucosa to hyperplastic area and progressed to dysplasia, carcinoma in situ, and finally to invasive carcinoma. The purpose of this study is to investigate the histological types of the transitional area from normal oral mucosa to invasive carcinoma for the baseline data to search intermediate end point markers for early detection of OSCC. For this purpose, we reviewed the 85 patients who were diagnosed as OSCC in the Department of Oral Pathology, Yonsei University College of Dentistry, from 2002 to 2008. We classified these histopathologic findings by light-microscopy, according to the histologic pattern of transitional areas. As results, stepwise transformation from normal oral mucosa, to dysplasia and to OSCC was shown in 47 patients. Intermittent lesions were seen in 16 patients, in which normal oral mucosa, dysplasia, and OSCC were alternately arranged. Twenty two patients showed abruptly transformed to OSCC from normal oral mucosa. These preliminary data will be used for searching biomarkers for early detection of OSCC."