Amino acid transporters play an important role in supplying organic nutrient to cells. The expression profile ofL-type amino acid transporter 1 (LAT1) and its subunit 4F2 heavy chain (4F2hc) on different differentiation stages in4-NQO induced rat tongue carcinogenesis was examined using immunohistochemical analysis. The gradually increasingLAT1 and 4F2hc expression detected during the multistep progressive change shows that the protein may have an importantrole i n the multistep tongue c arcinogenesis. Conclusively, LAT1 and 4F2 hc c an b e a useful b iomarker f or abetter understanding of multistep tongue carcinogenesis, while the specific inhibition o f LAT1 and 4F2 hc would be anew rationale for suppressing tumor cell growth in tongue cancer.

A patient complaining of severe pain in the right submandibular area showed a huge sialolith in radiogram. Duringthe operation, the submandibular gland was much indurated, and large amount of pus was discharged out at an incisionof the salivary gland. The removed salivary gland contained a huge sialolith in the major excretory duct of submandibulargland, which had an intact grayish-white surface in ovoid shape. In the histological examination its excretoryducts were extensively dilated without extravasation of saliva, and the involved salivary gland was almost destroyedby the granulomatous r eaction. Most of a cinar cells were d isappeared and r eplaced by ductal cells filled withexudative materials. The microsections of sialolith showed typical laminar structures of calcification containing amorphousbasophilic material in the center, in which a lot of Gram positive and Gram negative microorganisms werefound. In the center of sialolith numerous microorganisms were admixed with mucinous materials which were stronglypositive for the antibody of mucin-1, and formed multiple colonies. In the periphery of the bacterial colonies prolinerich proteins (PRPs) were condensely localized, and followed by the consistent positive reaction of transglutaminase 4(TGase-4). These data suggest that the sialolith of this study is formed from the primary nidus of bacterial colonyaggregated with salivary mucin-1 and PRPs by the crosslinking reaction of TGase-4.

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.