Epithelial-myoepithelial carcinoma (EMC) is uncommon, low-grade malignant epithelial neoplasm, and composed ofductal and large, clear-staining myoepithelial differentiated cells. we found four cases of EMC patients among thosewho visited the dental hospital of Seoul National University from 1998 to 2008. Immunohistochemical staining with epithelialand myoepithelial marker was done to verify the characteristic biphasic cell population. In our cases, the meanage of the patients was 61.5 years, which is consistent with previous reports. However, all the patients were female,and submandibular glands were the most affected sites. This is different from other reports that parotid gland was themost affected sites. There was recurrence and metastasis to lung in one out of four cases.

In order to know the degenerating state of postnatal cleft lip tissue, total 23 cases of lip biopsy obtained from cleftlip surgery were collected and examined pathologically. The cleft lip tissues characteristically disclosed epithelial hyperplasia(13/23), stromal myxoid degeneration (20/23), salivary gland degeneration (1/23), muscular degeneration(11/23), and sebaceous gland hyperplasia (15/23), melanocytic infiltration (5/23). The epithelial hyperplasia was markedwith hyperkeratosis and basal hyperplasia, which was usually coincident with the myxoid degeneration of underlyingconnective tissue. The myxoid degeneration was diffuse in the deep connective tissue with chronic inflammatoryreaction,and followed by extensive muscular degeneration. The sebaceous gland hyperplasia was usually predominantin the skin area of the cleft lip. In this study the lip biopsy from 30years old patient still showed remarkable retrogressivedegeneration of lip tissue. Therefore, it is considered that the postnatal cleft lip tissue is continuously degenerative,and its retrogressive change gradually affects the deterioration of perioral muscular structures, consequentlyresulted in the failure of lip functions as well as further bizarre malformation of oro-facial shape duringthe postnatal period. These data also indicate that the biopsy of postnatal cleft lip should be recommended to know itsvariable degenerating status and to perform the proper rehabilitation surgery of cleft lip.

We conducted a series of in vitro experiments to evaluate the anticancer effect of photodynamic therapy using hypericinand 532㎚ DPSS (diode pumped solid state laser). The cultured KB cells were treated with serial concentrationsof hypericin ranging from 0.01㎍/㎖ to 5㎍/㎖ (two-fold dilution) with variable laser dosage (10J, 20J, 30J). The cellviability was evaluated by MTT assay. The type of cell death was detected by fluorescent microscope using Hoechst33342 / PI (propidium iodide) stain methods. In this study, IC50 value with hypericin-mediated PDT with 10J DPSS laserwas 35 ng/ml. The maximum cytotoxicity with Photofrin II-based PDT was observed at high drug concentrations(>90 ng/ml) independent with laser dose. And the in vitro PDT effects depended on the laser dose and drugconcentrations were displayed by the difference in the type of cell death, namely apoptosis or necrosis. According tothis result, the hypericin based photodynamic therapy with DPSS laser was effective photodynamic therapy.

Adherent cells, such as those found in epithelial tissues, must be physically associated with extracellular matrix(ECM)components to survive. Though stimulation by growth factors is an essential factor in cell survival, normal cellsalso requires cell adhesion to ECM proteins. The cessation of these anchorage-mediated signals seems to be a commonmechanism to physiolog ically t erminate t he l ife cycle of t hese c ells b y apoptosis. This form o f cell death has beentermed anoikis.In cancer, resistance to anoikis of cancer cell is important in invasion and metastasis. The presentstudy investigated the intracellular mechanism involved in anoikis, especially in cells treated with epigallocatechin-3-gallate(EGCG). To induce anoikis, cell culture plates were coated with 10 ㎍/ml poly-HEMA. A549 lungadenocarcinoma cells were grown in RPMI 1640 medium with/without 10% fetal bovine serum, and then cells were replatedon cell culture dishes coated with poly-HEMA in the presence or absence of serum. On the other hand, EGFRinhibitor, PI3K inhibitor, and EGCG were treated to the anoikis status cells, in order to evaluate the factors ofanoikis. The result revealed that growth factors or loss of adhesion can increase phosphorylate Akt. In addition, lackof cell adhesion fails to activate pro-apoptotic factors directly. Activity of Erk kinase depends on not only EGFR signalingbut also cell adhesion. Akt activation is mainly affected by EGCG whereas Raf-1 activation is controlled by thepresence of cell contact. In addition, EGCG increased the level of NFkB, whereas phophroylated PTEN and total PTENwere not different. In this report,increase of NFkB was correlated with Akt phosphorylation, suggesting that EGCG canprotect cells from detachment–induced cell death through Akt activation and subsequent NFkB.

Green tea, derived from the plant Camellia sinensis, is one of the most common beverages consumed worldwide.Epigallocatechin-3-gallate (EGCG) is the most abundant and bioactive polyphenolic constituent in green tea.Understanding how intracellular signaling pathways respond to EGCG may provide a clue to the difference of cell responsesand basis for usefulness of EGCG as a chemopreventive and/or chemotherapeutic agent. In the present study,we tried to check whether EGCG could be a useful agent in chemotherapeutic treatment of oral squamous carcinoma.Furthermore, we investigated which signaling pathway is involved in biologic activities of EGCG. EGCG induced the celldeath of oral squamous carcinoma cells. Furthermore, it increased phosphorylation of Akt in serum-strarved oral squamouscarcinoma cells. But, initial increase of Akt activation did not affect cell survival. Activities of Raf-1 and Erkshowed inconsistent response to EGCG treatment, but Erk phosphorylation is consistent with Raf-1 activity in YD 10Bcells. These changes of Raf-1 and Erk activity in EGCG treated cells were different depending on cell line type.Supposedly, the difference of cell component may affect the Raf-1 and Erk reactivity to EGCG treatment. Akt activationby EGCG is independent on activities of PDK1 and PTEN, and expression of bax and bcl-2 proteins were notchanged by EGCG treatment. Therefore, EGCG treatment did not induce the apoptosis of YD 10B cell. On the otherhand, vascular adhesion molecule (VCAM) was decreased by EGCG treatment, so it is possible that decrease of VCAMcan play certain role in survival and/or cell death in EGCG treated cells.

The purpose of this study was to evaluate the role of survivin in various salivary gland tumors. For this study, total18 cases of salivary gland tumors; 6 cases of benign and 12 cases of malignant tumors were used as experimentalgroup. In benign tumors; pleomorphic adenoma, oncocytoma, and in malignant tumors; adenoid cystic carcinoma, mucoepidermoidtumor, high grade and low grade malignancy each, adenocarcinoma, acinic cell adenocarcinoma cases wereincluded. And for the control group, fresh submandibular glands were attained from gnathosurgical specimen. All thespecimens, experimental, control group were fixed in 10% neutral formalin solutions, embedded in paraffin, sectioned5um or more in thickness, stained with the hematoxylin and eosin, mounted and examined under the microscope. Forthe immunohistochemical studies, all the specimens were activated with survivin monoclonal, and secondary antibodiesas usual manners, and taken photos on various pathologic fields analysed with the image analysis system, and evaluatedthe positive and negative stained area in the tumors on each images and statistically analyzed with SPSS 15.0program. Attained result as follows. In control group, in part, acini cells show positive reaction on the nuclei, negativeon the all most of the cytoplasm, more intense reaction on the cytoplasm and nuclei on the serous demilune(47.33%). In experimental group, all the specimens show survivin positive reaction on the cytoplasm with/or withoutpositive reaction on nuclei according to the tumors, in benign tumors; pleomorphic adenoma (63.48%), oncocytoma(56.31%), each and in malignant tumors; adenoid cystic carcinoma (87.6%), acinic cell adenocarcinoma (56.35%). adenocarcinoma(67.47%), mucoepidermoid carcinoma, low grade (70.76%). high grade (55.23%). Survivin expression showshigher in tumors compare to that on the control group (p<0.05), but between the malignant tumors no significant arenot noted(p>0.005). Survivin expression is strongly related to the malignancy of salivary gland tumors.

A case of chronic osteomyelitis caused by prolonged intake of bisphosphonate showed multiple recurrences involvingextensive area of mandibular body. After saucerization the removed bony fragments were decalcified, microsected in 4㎛ thickness, and stained with hematoxylin and eosin, Masson trichrome, von Gieson, and periodic acid Schiff reaction.The inflammatory lesion contained fragile osteophytes easily propagated into sequestra. Histologically, this osteomyelitiswas relatively less suppurative but almost granulomatous, highly infiltrated with small round cells and macrophages.The osteophytes were frequently deposited on the old lamellate bone, but their ossification was extremely immatureand frequently filled with sclerosed collagen bundles positive for von Gieson stain. In the polarizing microscope observationunder Masson trichrome stain the newly deposited osteophytes were lack of birefringence image of Haversiansystem contrast to the old bone nearby. Therefore, we presume that the prolonged intake of bisphosphonate may inducethe immature osteophytes lack of Harversian system, which are partly filled with sclerotic collagen bundles, andthe immature bone is easily undergone extensive degeneration and necrosis, resulted in the inflammatory foci for multiplerecurrent osteomyelitis.

Although the sparganosis involving soft tissues, i.e, tongue, cheek, etc., has been frequently reported, the mandibularinvolvement of sparganosis is not reported up to date. We present a case of intraosseous sparganosis involving wholemandible, which was clinically diagnosed as chronic osteomyelitis. After surgical operation of saucerization for the treatmentof chronic osteomyelitis the removed specimens were pathologically examined and finally turned out intraosseoussparganosis. Radiological findings showed irregular multiple radiolucencies in round to ovoid shape throughout both mandibularbody areas, of which peripheral rarefying radiopacity was less remarkable compared to the ordinary osteomyelitis.However, the radiolucencies of periapical granuloma, #34-36, were closely associated with the osteolytic lesions of mandibularbody. Pathological examination showed a tunnel like space for the passage of sparganum larva, and heavy infiltrationof eosinophilicleukocytes. And more, the parasitic tegument materials were found admixed with eggs in thegranulomatous lesion, which were gradually degraded and resolved. Taken together, we presumed that the mandibular inflammatorylesion was primarily involved with sparganosis and secondarily aggravated by the periapical infection of#34-36.

We conducted growth inhibition tests on oral microorganisms using three strains of Lactobacillus spp. which are widelyknown as their probiotic properties. In these experiments, we measured the number of oral microorganisms after directlycontacting lactobacillus with them. In addition, we conducted a similar study using yogurts which are well knownas a p robiotic food. I n these yogurts, w e identified t he t ype o f lactobacilli by 1 6s r RN A nucleotide analysis. In o urstudy, the growth of most of oral microorganisms were inhibited by lactobacilli, and we also found that yogurts had thehighest effectiveness in inhibiting the growth of most of oral microorganisms. The lactobacilli contained in the yogurtswere identified as Lactobacillus casei, Lactobacillus paracasei, Lactobacillus helveticus, Lactobacillus casei, andLactobacillus helveticus.

The polarizing images of hard tissues including bone and cementum show characteristic features of different birefringencefortheir microstructures. Nevertheless, the clear mechanism of the amplified birefringence under polarizingmicroscope has not been well understood. We hypothesized that the unique polarized light could be accumulated in themicrotubules due to the decreased refractory angle by the inside lower-density matrix, and then the accumulated light inthe microtubules could be dispersed brightly. In order to elucidate the polarizing effect on the microtubules, the dentinaltubules in different conditions were observed, and compared with each other to explain their birefringence phenomena.In the decalcified sections of normal tooth, the dentinal tubules located near the pulp chamber showed strong birefringence,while the sclerosed dentinal tubules near the dentino-enamel junction did not show the birefringence. Thebirefringence was more conspicuous in the longitudinal sectionsof dentinal tubules than in the cross sections. In the decalcifiedsections of complex odontoma, which produced abnormal and immature dentinal tubules, the birefringence wasnot observed in the shrunken dentinal tubules filled with dense materials, while the peritubular matrix showed clearbirefringence. The birefringence was also observed in the collagen fibers in the connective tissue, and continuouslystrong in the immature cemental materials containing precollagen fibers. However, the highly mineralized osteodentinedid not show the birefringence. Taken together, these data suggest that the microtubules composed ofless-dense matrixthan the background tissue, i.e., dentinal tubules, Haversian canals, etc., produce the amplified birefringence by thepolarizing light according to the hypothesis of microtubule refraction.

Cyclosporine A, immunosuppressive agent, has been applied to treat cancer cells. IHOK(Immortalized human oral keratinocyte)have been accepted as a model system for HPV-linked oral carcinogenesis. It is important to pursue the apoptosisof IHEK culture model by CsA related to the pathogenesis of oral squamous cell carcinoma. But CsA effect on immortalizedhuman oral keratinocyte(IHOK) remains unclear. Transglutaminase 2(TGase 2) which is expressed and activatedin tissue where epithelial cells undergo apoptosis has been used as a marker for apoptotic cells. The purpose ofthis study were to examine the effect of CsA on the proliferation and apoptosis of cultured NHOK by TGase 2expression. After IHOK and HN 12 cell line were treated by 0.1, 1.0 and 10ug/ml Cs A, growth curve, MTT assay forsuccinyl dehydrogenase activity, TGase assay for TGase 2 activity and immunoslot blotting for TGase 2 ptorein expression,and TEM features were done. MTT assay showed about 80% cell viability of HN 12, while about 50% of IHOK at10ug/ml CsA. Growth curve showed normal S curve on control and DMSO, while IHOK was more decreased after 3 daysof higher CsA treatment. Apoptosis index showed about 30% of IHOK and 15% of HN 12, respectively. TGase 2 activityand protein expression of IHOK was the highest at 10ug/ml CsA, while HN 12 was slight higher than control. TEMshowed chromosome fragmentation and margination, and vacuole formation in cytoplasm of IHOK after CsA treatment. Itsuggested that higher cyclosporine A might induce apoptosis of IHOK as Intermediate stage cells correlated with increasedTGase 2 activity and protein expression.

Elevated expression of survivin is strongly associated with tumorigenesis and even in human common cancers. Oralsquamous cell carcinoma (OSCC) is the 7th most frequent cancer in human and responsible for more than 90% of all oralcancer. The purpose of this study is to confirm whether survivin is associated with oral carcinogenesis, expecially has arole in the development of OSCC. For the control group; 3 specimens obtained from normal oral mucosa without any inflammatoryreaction were used a nd for the experimental group, specimens obtained f rom 18 sub jects of OSCC; 6 subjectsfrom Well differentiated type OSCC; 4 subjects from Moderately differentiated type OSCC; 3 subjects from Poorlydifferentiated type OSCC; 3 subjects from Verrucous carcinoma: and 2 subjects from C arcinoma in situ were used.All the specimens were embedded in paraffin, sectioned 5 μm or more in thickness, and stained with hematoxylin-eosin. For immunostain, the specimens were incubated with 1;200 diluted primary antibody (anti-survivin monoclonal,Biocare Inc, USA), followed by the secondary antibody(NovoLink Polymer detection system, Novocastra Lab., UK).The bound antibodies were visualized by addition of diaminobenzidine tetrahydrochloride(DAB) for 30 minutes at roomtemperature. The specimens were counterstained with Mayerʼs Hematoxylin and mounted. Quantitation of immunoreactivitywas performed under the light microscope with the following criteria ; Intensive reaction; +++, Moderate reaction;++, Minimal reaction; +. Using the image analyzer(Korea Optical System), immunoreactivity of tumor cells invarious field was measured and statistically analyzed with SPSS 15.0 Program. The results were as follows: Expression ofsurvivin in OSCC was significantly increased in the nucleus and the cytoplasm of OSCC as compare to those of controlgroup (p<0.05). Expression of survivin in the nucleus and the cytoplasm of the cells in OSCC is correlated with the cellularmalignancy (p<0.05). Expression of survivin in Poorly differentiated type OSCC partly correlated to some extent tocellular malignancy (p<0.05). These results suggest that expression of survivin in OSCC is closely associated with to thedevelopment, and malignancy of the OSCC, b ut it is not enough to be used a s a marker f or the c ellular malignancy.Further studies are needed to relate the expression of survivin to cellular malignancy.