Candida albicans and their associated Candida species are opportunistic pathogens which exists as normal flora inthe oral cavities of healthy individuals. In response to physiological changes in the host, these yeasts can becomepathogenic, resulting in oral candidiasis. The rapid detection and identification of Candida species in clinical laboratoriesare extremely important for the management of patients with hematogenous candidiasis. The presently availableculture and biochemical methods for detection and species identification of Candida are time-consuming and lackthe required sensitivity and specificity. In this study, we have established a seminested PCR (snPCR) using universaland species-specific primers for detection of Candida species in saliva. The universal outer primers amplified the 3endof 5.8S ribosomal DNA (rDNA) and the 5end of 28S rDNA, including the internally transcribed spacer 2 (ITS2), generating350- to 410-bp fragments from the four commonly encountered Candida spp., viz., C. albicans, C. tropicalis,C. glabrata, and C. parapsilosis. The saliva from 331 healthy and, over 50 years of aged people lived in Dong-gu,Gwangu city, was collected. Total DNA were extracted by Hoffman-Winston yeast total DNA prep. method and performedt he s nP CR. R esults appeared to b e negative on 292 people ( 88.2%), however, 2 6 people ( 7.9%) were p ositiveCandida albicans, 6 people (1.8%) were positive Candida glabrata, 5 people (1.5%) were positive Candida tropicalis, andonly 2 person (0.6%) were positive Candida parapsilosis. These result showed that detection and identification ofCandida species could be established by saliva analysis, so that snPCR on saliva is useful method of diagnosis of clinicalfields.

 Oral squamous cell carcinoma (SCC) is one of the leading causes of cancer mortality worldwide. It is generallythought that adjuvant chemotherapy provides modest prolongation of survival in various carcinoma. Docetaxel(Taxotere, TXT) play a significant role in the treatment of various solid tumors of epithelial origin. CsA(immunosuppressive drug) was widely used as adjunct for the treatment of cancer. Thus, it is important to pursue theapoptosis of IHOK and oral SCC induced by TXT combined with CsA related to the pathogenesis of oral SCC. But TXTcombined CsA effect on IHOK and oral SCC remains unclear. After cultured IHOK and HN 22 oral squamous cell carcinomacell line treated by 10 nM TXT and 1 μM, and caspase inhobitor, respectively, apoptosis index, cytochrome cand caspase-3 -8, -9 mRNA expression by RT-PCR, and procaspase-3 protein amount by immunoslot blotting wasprepared. The purpose of this study were to examine the TXT-induced apoptosis pathway via caspase activation byCsA enhancement, and to apply these results to an effective therapeutic treatment plan for oral SCC by TXT combinedCsA . 10 nM TXT showed about 60%, 55% celluar apoptosis of IHOK and HN 22, cell line, respectively, while CsA alonedid not induce apoptosis in IHOK and HN 22 cell line. 1 μM CsA combined with 10 nM TXT increased apoptosis inIHOK and HN 22 cell line through caspase-3 and cytochrome c mRNA expression, while could not effect on caspase-8and -9. Caspase inhibitor suppressed apoptosis of IHOK and HN 22 cell line induced by a combination of 1 μM CsAand 10 nM TXT. Immnoslot blotting showed procaspase-3 activation by a combination 1 μM CsA and 10 nM TXT, whilecaspase inhibitor inhibited activation. It suggested that a combination of CsA and TXT might induce increased apoptosisof IHOK and HN 22 oral squamous cell carcinoma cell line through caspase-3 activation. This treatment with acombination of TXT and CsA may be an effective therapeutic strategy for oral squamous cell carcinoma.

 The transcription factor nuclear factor-kB (NF-kB) plays an important role in regulating cell growth, apoptosis,and metastatic functions. Constitutive activation of NF-KB has been observed in various cancers; however, molecularmechanisms resulting in such activation remain elusive. Numerous evidences showed that over expression ofTGase 2 might be linked with constitutive activation of NF-KB. To understand the pathways responsible for constitutiveactivation of NF-kB is important for rational design of NF-kB inhibitors for cancer therapy. Human salivarygland adenocarcinoma has been most aggressive solid tumors. Current therapy does not significantly improvesurvival rates. Thus, to investigate new therapeutic modalities against this adenocarcinoma is necessary. The purposeof this study was to study a constitutive activation of NF-kB with the expression of TG2 in SGT cell line origiantedfrom human salivary gland adenocarcinoma by TGase 2 activity, RT-PCR and immunoslot blotting method.SGT cell line showed the highest TGase 2 activity and NF-kB activation than any other cell line. All the cell linesshowed increased NF-kB mRNA activation after A231027 treatment than that of control. In immunoslot blotting,SGT cell line showed NF-kB activation correlated with TGase 2 expression after A231027 and BSA. It suggested thatthere might be a direct correlation between TGase 2 expression and NF-kB activation in SGT cell line.

 The organotypic raft culture model has been shown to be a useful method for examining the effects of biochemicalmanipulation on various epithelial cell types, using in vitro conditions that simulate the in vivo environment of thetissue of origin. To investigate this method as a model for photodynamic therapy (PDT), we cultures the oral squamouscarcinoma cell line YD-10B on fibroblast-containing collagen gels at the air-liquid interface and assessed the efficacyof PDT using a photosensitiser 5-ALA-hexenyl ester. PDT effect on YD-10B organotypic raft cultures after twenty-four hours was determined. The number of residual cells was significantly reduced in comparison to control at allfour different conditions. PCNA immunostaining and TUNEL assay revealed that PDT inhibited cell proliferation andincreased apoptosis. These findings suggest that the organotypic raft culture model provides an effective and rapidlaboratory method of investigating strategies for PDT on oral precancerous lesions and squamous cell carcinomas.

 Plasma cell myeloma is malignant disease of plasma cell in the bone marrow. Myeloma accounts for about 1% of allcancers. The solitary plasma cellmyeloma is rare tumors and account for less than 10% of plasma cell neoplasm. It isoften progress to multiple myeloma at 30~40% despite successful local treatment with surgery and radiation therapy.We are reporting a case of solitary plasma cell myeloma on anterior Maxillary region that developed after kidneytransplantation and immunosuppressive therapy.

 The eukaryotic translation initiation factor 5A (eIF5A) is a ubiquitous protein of eukaryotic and archaeal organismswhich undergoes hypusination, and known to play pivotal functions for the synthesis of proteins involved in cell proliferationand cell cycle control. Its nuclear localization has an important implication for the eIF5A functions in nucleus,but the evidence of the nuclear translocation is still in controversy. This study is aimed to elucidate the nuclearlocalization of eIF5A in the epithelial cells of oral leukoplakia by the immunohistochemistry using trypsin digestion toremove their cytoplasms. The keratinocytes of the acanthotic and basal cell layers in oral leukoplakia showed thecomplete removal of their cytoplasmic components, but the nuclei of those cell layers were remained on themicrosection. The immunostainings using both polyclonal and monoclonal antibody against eIF5A showed the strongpositive reaction in the nuclei remained after trypsin digestion. And the immunostaining was more intensely expressedin the nuclei of the basal and suprabasal keratinocytes than in the nuclei of the upper spinous keratinocytes. Thesedata directly indicate the post-translationally modified eIF5A is abundantly localized in the nuclear matrix componentsincluding nucleoli, which are resistant to the trypsin digestion. It is also presumed that the nuclear eIF5A localized atthe trypsin resistant nuclear matrix, i.e., histone and r ibosomal proteins, may be closely relevant to the control ofmRNA production or to the nuclear-cytoplamic trafficking for mRNA transportation.

 Human papillomavirus (HPV) has been classified as one of the causing factors of head and neck squamous cell carcinoma(HNSCC). However, little is known about HPV-related carcinogenesis in HNSCC. The purpose o f this s tudy i sto characterize immortalized human oral keratinocyte (IHOK) transfected by HPV16 E6/E7, IHOK/hcdk4 (IHOK transfectedby pLXRN-hcdk4) and IHOK/hcdk4/hTERT (IHOK transfected by pLPC-hTERT-hcdk4) to reconstitute HNSCC invitro. Conclusively, we established a new immortalized cell lines, IHOK/hcdk4 and IHOK/hcdk4/hTERT, to understandmultistep carcinogenic process of oncogenic HPV16 E6/E7 in HNSCC.

 Desmoplastic ameloblastoma (DA) and Ameloblastic fibroma (AF) show common histopathologic features such as enamelorgan like epithelial islands or cords on the background of abundant fibrous stroma. Despite their similar histopathologicfeatures, it was reported that they have different pathogenesis and clinical behavior. The purpose of this studywas to rev iew clinicopathologic features of DA and AF among Korean subjects. 7 cases of DA and 4 cases of AF wereretrieved from the files of Seoul National University Dental Hospital (SNUDH), and their clinical features, radiographicfindings, and histopathologic features were reviewed and compared. DA occurred in 3 males and 4 females. They occurredfrom 24 to 62 years of age, showing the mean age of 42.7 years. 5 of the 7 tumors occurred in the maxilla,and all of them in the anterior region, showing predilection for the maxillary anterior regions. There was norecurrence. Radiographically, they showed well demarcated unilocular or multilocular radiolucency. AF occurred in 5males and 2 female. They occurred from 6 to 29 years of age, showing the mean age of 14 years. All tumors occurredin the mandibular molar area. Recurrence was recognized in 1 case. Although DA and AF showed similar histopathologicfeatures, they showed different clinical behaviors. While DA showed predilection for the anterior maxilla, AF did forposterior mandible. While DA occurred mainly in adults, AF did in adolescents. Recurrence was recognized not in DAbut in AF. Therefore, DA and AF should be differentiated from each other in spite of similar histopathologic findings.

 Mucous retention cyst (MRC) is not uncommon in the pathology of maxillary sinus, which should be differentiallydiagnosed from chronic maxillary sinusitis. The main stream of diagnosis usually depends on the clinical symptoms andradiological findings. Thus it was sometimes puzzling to confirm the histological features of mucous retention phenomenonin the antral mucosa, when the specimen was from a limited portion or much degenerated by inflammatoryreaction. This study aims to define the histopathological features of MRC through reevaluation of MRCs (n=19) andmaxillary sinusitis (n=65) diagnosed previously. The present study classified three types of MRC, i.e., an extravasationtype, a luminal retention type, and a mixed type of MRC. The extravasation type MRC showed clear pseudocyst cavityunder sinus mucosa with infiltration of foamy macrophage, and the luminal retention type MRC showed mucous retentionin the luminal cavity of maxillary sinus accompanied with inflammatory reaction, and the mixed type MRCshowed the both features of extravasation and luminal retention type MRCs. Resultantly, among nineteen cases of MRConly three cases belonged to the extravasation type MRC, eleven cases belonged to luminal retention type MRC, andthree cases belonged to mixed type MRC, while two cases were turned out to be postoperative residual cysts of maxillarysinus. The MRCs examined in this study showed different pathological features from ordinary maxillary sinusitis,exhibiting the typical mucin retention phenomenon of extravasation type or luminal retention type with relatively mildinflammatory reaction with infiltration of mucin-pooled macrophages. However, the luminal retention type MRC waspredominant among the MRCs (11/17, 64.7%) and each of the extravasation and mixed type MRCs was only three casesout of 17 MRCs (17.6%). The extravasation type MRC characteristically produces a pseudocyst by the overexpressions ofmatrix metalloprotease-3 (MMP-3) and connective tissue growth factor (CTGF). Because not only the pathogeneticmechanism but also the prognosis of MRC is different from chronic maxillary sinusitis, we suggest that the MRC ofmaxillary sinus should be classified into extravasation, luminal retention, and mixed types in the histological observationsin addition to the clinical and radiological informations.

 PDT is an established cancer treatment modality. This can be attributed to the attractive basic concept of PDT;Combination of two therapeutic agents, a photosensitizing drug and light, which are relatively harmless by themselvesbut when combined, cause more or less selective tumor destruction. Hematoporphyrin-derived photosensitizers areknown to be stable and highly efficient. In this study, we conducted a series of experiments to develop light-inducedanticancer drugs against oral cancer cells. We tested the cytotoxicity of photodin by MTT assay and observed celldeath pattern (apoptosis or necrosis) by hoechst 33342 and propidium iodide staining methods after PDT. IC50 value ofphotodin was 0.65 ug/ml. At higher doses of photodin ( > 7.8 ug/ml), cancer cells died exclusively from necrosis afterPDT. By contrast, at IC50 value, photodin induced cancer cell to undergo apoptotic cell death. The induction begins approximately6 hours after PDT. We investigated intracellular localization of photodin by oral cancer cell via confocallaser scanning microscopy. Oral cancer cells dual-stained with photodin and organelle-specific fluorescence probes(Mitotracker, Lysotracker, ER-Tracker) revealed that an intracellular fluorescence distribution was restricted to cytoplasmiccompartments with no detectable fluorescence in the nucleus. Confocal images of cells containing photodinwere overlapped with the mitochondria-specific fluorescence probe images of the same cells. These results demonstratedthat photodin may play the role of a photosensitizer for oral squamous cancer cells without swelling andinflammation. Therefore, photodin-based PDT is a suitable treatment for oral cavity carcinoma patients.

Myoepithelioma is a rare tumor that seldom occur in the parapharyngeal space region. And an accurate diagnosis ofmyoepithelioma is very difficult due to its unusual location and cellular variation. Therefore, misdiagnosis of this neoplasmas more aggressive tumor can lead to unnecessary treatment. We experienced extremely rare case of myoepitheliomaarising in the deep lobe of parotid gland that is extended in the parapharyngeal space and reported it toa literature review.

Glandular odontogenic cyst (GOC) is a rare odontogenic cyst, which shows cystic structures lined by stratified squamousepithelium with various thickness. Glandular duct-like spaces lined by eosinophilic cuboidal or columnar cellsconstitute the epithelial surface. The purpose of this study was to present 7 cases of GOC retrieved from the files ofthe Department of Oral Pathology, Seoul National University Dental Hospital and to investigate the immunohistochemicalexpression of cytokeratins (CKs) in the epithelial components. A total of 7 GOCs were reviewedclinically and radiographically and immunostainning for CK 5, 7, 14, 18 and CK-pan were performed. There were fivemales and two females aged from 36 to 53 years (mean 45 years). Maxilla was more affected than mandibles (6:1).Radiographically, all cases showed multilocular radiolucencies with well-defined borders. Histologically, lining epitheliumof GOC was composed of nonkeratinized stratified epithelial cells with focal plaque-like or whirl pool-likethickenings. Surface epithelial layer contained eosinophilic cuboidal cells or mucous cells. Mucin pools of microcysticareas was also detected in the epithelium. Immunohistochemical study demonstrated that epithelium of GOCs was positivelyreactive for CK 5 7, 14 and CK-pan with a slight variation in their patterns and there was no reaction for CK 18.