Epithelial-myoepithelial carcinoma (EMC) is uncommon, low-grade malignant epithelial neoplasm, and composed of ductal and large, clear-staining myoepithelial differentiated cells. we found four cases of EMC patients among those who visited the dental hospital of Seoul National University from 1998 to 2008. Immunohistochemical staining with epithelial and myoepithelial marker was done to verify the characteristic biphasic cell population. In our cases, the mean age 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 the most affected sites. There was recurrence and metastasis to lung in one out of four cases.

Zygomycosis and aspergillosis are representative filamentous fungal infections in the sinonasal region. However, their combined form seldom occurs. This report describes one case of zygomycosis and aspergillosis occurring in a patient that did not have diabetes or any other immunocompromising conditions. The patient presented with a history of intermittent swelling and pus discharge from the gingiva of the right maxillary posterior teeth. The radiographs demonstrated a periapical radiolucency around the right maxillary first molar, together with mild haziness and mucosal thickening of the right maxillary sinus. U nder t he c linical impression o f odontogenic sinusitis, a Caldwell-Luc operation was performed. However, the final diagnosis based on microscopic examination was combined zygomycosis and aspergillosis. Previous studies of zygomycosis occurring alone describe a very aggressive clinical course, including necrosis of tissue,cranial nerve involvement and death. Our patient did not show any of these symptoms, and recovered after surgical debridement only. It can be concluded from the present case that the prognosis of fungal infections depends on the immune status of the host, rather than behavior of the fungi.

Cholesterol granuloma(CG) occurs frequently in association with chronic middle ear diseases, particularly diseases in the mastoid antrum and air cells of the temporal bone, and much less frequently in paranasal sinuses. It occurs frequently secondary to massive hemorrhage of oral and paraoral cysts. However, It has never been reported to occur solely without any association with preexisting lesion in the mandible. We experienced development of unusual cholesterol granuloma in the mandible. Seventy year old female presented diffuse hard swelling on the left mandibular area with lymphadenopathy of the left cervical lymph node. Radiographic examination showed a well circumscribed multilocular radiolucency resembling soap bubble appearance with tooth displacement and root resorption, leading to the radiogrphic impression of dentigerous cyst or odontogenic cyst or ameloblastoma. CT showed bucco-lingually undulating expansile lesion with corticated margin from the left posterior mandibular body to the anterior ramus, including #46, #47 and #48, and the mass showed slightly lower attenuation than muscle. leading to the impression of ameloblastoma. The mass after surgical excision composed of 2 sac like structures, measuring 4.0cm, and 2.7cm in diameter respectively. One sac was tightly attached to the #46, resembling dentigerous cyst. Microscopic examination showed a large number of cholesterol clefts in association with hemorrhage, hemosiderin pigments and foreign body giant cells. There was no evidence of cyst or other lesions

Oral malignant melanoma of the oral cavity is rare. Although the Asian population has a relatively high incidence of oral malignant melanoma in contrast to Caucasians, the clinical information in Korean has been rarely known. In addition, the clinical and histological classification of oral malignant melanoma has not been established up to now. So we investigated 26 cases of oral malignant melanomas on the basis of clinicopathological and immunohistochemical findings and reclassified the clinical and histological type. The results of this study are as followed. Oral malignant melanomas occurred at any age from 28 years to 73 years and their mean age was 58.6 years. Of 26 cases, 14 occurred in male and 12 in female. Oral malignant melanomas occurred almost in palate and/or maxillary gingiva (25 cases; 96.2%). Only one case occurred in mandibular gigiva. Oral malignant melanomas were clinically divided into macular(9 cases) and nodular type(17 cases), showing that the nodular type occurred more frequently. Oral malignant melanomas were histologically divided into in situ spreading(5 cases), invasive(13 cases), and combined type(8 cases), showing that the invasive type occurred most frequently. All cases showed positivity for S-100 and 15 cases(57.7%) for HMB-45 in immunohistochemical analysis. It was thought these results could provide basic data for the research on oral malignant melanoma in Korean and additional prospective and retrospective studies would be needed in order to find the relations with the prognosis of the patients

The support mechanisms that are involved in lymph node metastasis of oral squamous cell carcinoma remain largely unknown. Recent studies have demonstrated that tumor cells express chemokine receptors and use chemokines to metastasize to the target organ in many malignancies in humans There are few reports about the correlation between chemokin receptor CXCR-4 expression and clinicopathologic factors in oral squamous cell carcinomas. The object of this study was to evaluate the availabili ty of CXCR-4 expression as prognostic marker through correlation analysis of CXCR-4 expression in oral sq uamous cell carcinoma and its r elation to clinocopathologic factors and PCNA index. 80 we investigated CXCR-4 expression of 74 oral squamous cell carcinomas by immunohistochemistry. 44 out of 74 cases(59. 5%) showed CXCH-4 positive and 30 sampl es(40.5%) showed CXCH-4 negative. CXCH-4 expression showed statistically sig nificant correlation wi th lymph node metastasis(p=0.026) ‘ PCNA index (p=0.003) , survial rate(p=0.0003). From the results , it was suggested CXCR-4 oxpression might be useful a prognostic marker in oral squamous cell carClllomas

Amelobl astic carcinoma(AC) is a maJignant coun terpart of ameloblastoma. histologically characteri zed by amelobJastomatolls feature with obviollS cytologic a typi a . AC is a r are malignant tumor with poten t iaJ of metastasis‘ asssllmed to occur far less tha n 1% of ameloblastoma . Nearly 80% of ACs have been reported to occur in the mandibJ e. The allthors reviewed 5 cases of AC in Department of Oral PathoJogy. SeouJ National University from 2005 to 2007 clini copathologically according to age, sex. location and clinical findings. They occllrred at the age from 46 to 75 years wi th average age of 60 Four cases occurred in male and 1 in female‘ showing prediJ ection for ma le‘ While four cases occu rred in the maxilla , including 3 cases in the maxillary molar area and 1 in the maxiJJ a ry premola l‘ a rea, only 1 case occurred in the mandibJe. AC showing predorninance in the maxilla over t he ma ndible in our cases in contrast to other case reviews. Three patients presented painful large oral lllcer at the time of admi ssion, a nd other 2 patients presented swol1en mass around the gingivae and alveoJar bone While the clini cal impression of 3 patients were ma lignant tllmor, other 2 patients were amelboJastoma and nicotine stomatitis. The dllration of symptoms before final diagnosis has ranged from 4 months to 2 years Radiogr a phicalJy they showed poorly demarcated radiolucent lesion with irreg비 ar bony destruction. Resected tumors were measured as 6.0X4.5x4.0cm‘ 0‘ 7xO.5xO.3cm, 5.0 x 4.5 X5.0cm. 0.8xO.6 XO.5cm, and 5cm diametel mass respecti vely. Microscopically lymph node metastasis was confirmed in 1 case, but not in others . The tumors showed basic histologic featu re of ameloblastoma with apparent cytologic atypia sllch as pleomol‘ phism‘ hyper chromatism and atypical ffiJ tOSIS Individua l neoplastic cells displayed wide va riations from case to case‘ showing c lear cells with faint PAS positive granules‘ isolated round cells with abundant cytoplasm. s quamoid ceJls and polygonaJ cell s . [mmunohis toc hemical survey was done in 2 cases. all of which showed positivity to pan-cytoker atin a ntibody and p53 a ntibody‘ but negativity to HMB-45, S-100, and SMA One case recurred twice during 2 yeal's after surgery. But 3 cases showed no evidence of recurrence and metastas is. lt seems to us t hat AC have the potential of metastasis and reCllrrence.

Epithelial-mesenchymal transition(EMT) plays a pivotal role in the convers ion of earl y s tage tumors into invasive malignancies‘ and has been shown to be regulated hy the transcri ptional factor. Snail. Recent ly‘ actlvatlon of the phosphatidylinositol 3' kinase (PI3K)/따<:T axis is emerging as a centra l feature of EMT‘ However. it is unclear whether the phosphorylation of AKT regulate the expl'ession of s nail in ora l cancer cell underwent EMT. T。 investigate a role of p-AKT in EMT, we assessed the effects of inhibi ting p-AK1' activity in oral squamous can cer cells(KOSCC-25B) using PIAs, structurally modified phosphatidyli nositol ether lipid analogues(P1As) . PIAs de creased phosphorylation of c-Jun N-terrninal Kinase(JNK) and increased phosphorylation of glycogen synthase kinase 3beta(GSK-3beta). Inhibition of p-AKT ir빼ce d down regulation of Snail and Twist. but Sip1 regulated independent of p-AKT inhibition. Also inhibi tion of p-AKT dec reased cell migration and invas ion. Therefore our results implicate that p-AKT may contribute to the translocalization of sna il in the EMT associated with canceJ cell rnigration and invasion

Cholesterol granuloma(CG) occurs frequently in association with chronic middle ear diseases. pa rti cul arly dis eases in the mastoid antrum a nd ai r cells of the tempora l bone. and much less frequent ly in paranasal sinuses, It occurs f1'eq uentJy seconda1'Y to massive hemor1'hage of oral and pal'aol'aJ cysts, Howeve1'. It has nevel' been I'eported to OCCUI' solely wi thout any association of pl'eexisting lesion in the mandibJe We expel'ienced development of unusuaJ cholestel'ol granuloma in the mandible, Seventy year old female pl'e sented diffuse ha1'd swelling on the left mandibular a rea with Iymphadenopathy in the left cer vical Iymph node Radi og1'aphic exarnination showed a well circumsc ribed multi locular radiolucency resembling soap bubble appeara nce with tooth di s placement and root resorption‘ leading to the radiogrphic imp1'ession of dentigerous cyst 0 1' 。dontogenic cys t or amelobJas toma, CT showed bucco-lingua lly undul ating expansi le lesion with co rticated ma l'gin from the left posterior mandibular bocly to the anterior ramus. including #46, #47 ancl #43. and the mass containing in the lesion showed s lightly lower a ttenuation than muscJe leading to the impression of ameloblastoma, The mass aftel' surgical excis ion composed of 3 sac like structures, measuring 4,1 cm, 1, 3cm ancl 1.4cm in diame ter respectively, One sac was t ightl y a ttached to the #46. l'eRembling dentigerous cyst, Mi croscopic examination showed a large numbel' of c h이 es te rol clefts in association with hemol'rhage, hemosiderin pigments and fO l'eign body giant cells, There was no evidence of cyst 0 1' other lesions, CG should be taken into diffe l'enti a l diagnosis in addition to odontogenic cysts and tumors when radiographica lly well ci rcumscribed multilocuJal' radiolucent lesion occurs

Although a number of molecules have been implicated in the metastasis of oral squamous cell carcinoma (OSCC) , the precise molecular mechanisms that deterrnine the direction of rnigration and invasiveness of OSCC cells into the lymph nodes remain unclear, Chemokines are a superfarnily of small structurally related heparin- binding proteins‘ which have been identified as attractants that control the rnigration of leukocytes‘ especia lly during imrnune and inflammatory reactlOns Moreover, recent studies have demonstrated that several types 。f cancer express chemokine receptor‘s and use chemokines to metastasize to the target organ, However, there h ave been few reports on biological behaviors by downregulation 0 1' CXCR-4 in ora l cancel‘ cells We tried to screen several OSCC cell lines in order to obtain a suitable cell line model which had the cha ract eris tic of the constitutive ly expressed state of CXCR• 4 Of the several OSCC cell lines, only KOSCC-25B showed the high expression of CXCR-4 in both RT-PCR and Western blot analysis, siRNA-CXCR-4 infected subclones of KOSCC-25B(Si, 3‘ Si 1이 showed downregulation of CXCR-4 expression as expected‘ At serum-free co ndi tion‘ Si.3 s ubclone s ignif icantly decreased cell proliferations at 24 h and 48h and Si, lO subclone significant ly dec reased cell proliferations at 24 h Si ,3 clone dec reased to 67 ,4% and Si,lO clone to 65 ,5% in comparison to vector infected cells These data suggest that the downregulation of CXCR-4 expression could induce anti-rnigratory and ant i- rni g ratory effect

Epithelial myoepithelial carcinoma(EMC) is an uncommon malignant sali va ry gland neoplasm, compri sing about 1% 。f salivar y gland neoplasms, They are histologically composed 01' biphasic cell s such as myoepithelial cells and ductal cells EMC occurs predominantly in the major salivary glands, par t icularly in the par otid gland, They have been reported to occur onJy 10-15% in t he intraoral minor salivary glands, The authors experi enced 4 cases of EMC in Department of Oral Pathology in Seoul National University Dental Hospital from 1995 to 2007‘ and reported them with revi ew of li terature, They occurred at the age [rom 34 to 75 years with average age of 54, Three cases occurred in f'emale and 1 in male, showing predominant occurrence in female, Al I of them occurred in the f100r of mouth Three patients presented localized swollen mass at the time of admission, One patient manifested pain with surface n ecrotic ulcer, and others did not complain any symptoms, The duration of symptoms before diagnosis has ranged f rom three mont hs to 2 years in our cases Microscopically, they growed in double layered ductal structure composed 。f' ductal cells of the inner luminal layer which showed positive immunohistochemical reaction to cytokeratin and rnyoepithelial cells 01' the outer peripheral layer identifi ed by the positive reactivity to S-100 and srnooth muscle ac tin antibody, They did not show perinem al invasion‘ but invasíve growth into adjacent tissue, AII of them did not show in vasion into t he underlying bOl1e While 3 pat ients were treated with total excision of tω110 1' mass wi thout n。 evidence of recurrence a ncl metastasis, a 75 year old patient gave up receiving t reatment at the t irne of diagnos is, and then died 01' the cancer 5 years after init ial diagnosis, It seems that EMC of the intraoral minor salivary gland is a tumor 01' low grade malignancy with low potent ial of recurrence and metastasis

This research was designed to investigate changes of growth factors and bone matrix proteins during the bone healing processes using immunohistochemistry and in situ hybridization. Especially this study was focused on the changes of bone matrix and growth factors around the titanium implant. Threaded implants were introduced into the long bone of tibia. Time dependent changes of several bone associated protein and and its mRNAs were observed. Proteins investigated in this study are collagen, osteonectin(ON), osteopontin(OPN), osteocalcin(OC). Expression of the proteins were measured using immunohistochemistry. VEGF and ON were measured using in situ hybridization, and northen blot technique. Bone regeneration were observed as early as the third day of experiment. Matrix proteins and growth factors observed around implant were identical to the proteins observed in the control group. The expression of the ON, OC and VEGF were observed mainly in the osteoblast-like cell on the surface of new bone around the implant and the cells lining the margin of bone defect apart from the implant. The observation may not result from direct osteoconducting activities of titanium but by passive adsorption of extracellular factors which has bone inducing capacities. These passive adsorption results in the immobilization of the growth factors and consequent prolongation of the activities.

ISPARC (Secreted protein acidic and rich in cysteine) is detected in the bone stroma during wound-healing process. To understand the roles of SPARC in bony wound-healing process, SPARC cDNA were synthesized from rat calvarial osteoblast culture, and SPARC protein was synthesized from the cDNA. To observe the effects of SPARC protein on the differentiation of osteoblasts, bony defect were made on rat tibia, and the distributions of bone matrix related proteins and SPARC were investigated using immunohistochemistry. In the rat osteoblastic culture using untreated plastic surface, Collagen-SPARC treated surface presented higher protein synthesis than untreated surface or only collagen treated surface. SPARC synthesis in the bony defect of rat tibia was augmented by introducing SPARC to the bony defect. SPARC synthesis were increased from the center of the defect compared to the control. SPARC synthesis in cells of the center of the defect was increased and maintained for 14 days. We could conclude that SPARC introduction may affect the early bone matrix formation, including SPARC, and mineralization in bony wound healing process.

Adenoid cystic carcinoma(ACC) is one of the most common malignant tumors of minor salivary glands and can also arise in a variety of sites in the head and neck including the major salivary glands, the esophagus, the lacrimal glands. ACC shows slow but relentless growth, so it shows long-term recurrence. The various reports about prognostic factors which influence the recurrence pattern are introduced but the reports about prognostic factors are rare in Korean adenoid cystic carcinoma patients. We examined 40 ACC patients who finally diagnosed at Department of Oral Pathology, Seoul National University Dental Hospital. Clinicopathologic and immunohistochemical features were reviewed and factors correlated with recurrence and survival were analyzed. The 5-year survival rate of T3,T4 stage was 31.2%, while that of the T1,T2 stage was 88.2%, and the difference 5-year survival and T stage was statistically significant. The rate of local recurrence was 20% and the rate of distant metastasis was 27.5%. Mean recurrence time were 4.8 years and 5.2 years. There was no significant difference between age, sex, T stage, TNM stage, histologic type and recurrence. But the high T stage and the solid type recurred more frequently. There was no significant difference between recurrence rate, 5-year survival rate and Ki-67, MVD expression. But the higher expression of Ki-67, MVD show the higher recurrence rate and the lower 5-year survival rate

The adenomatoid odontogenic tumor(AOT) is a benign tumor of odontogenic epithelium characterized by slow but progressive growth and rare recurrence. Tumor growth may cause displacement of teeth rather than root resorption. The AOT appears in 3 clinicotopographic variants such as follicular, extrafollicular, and peripheral. The follicular AOT mimics a dentigerous or follicular cyst and the extrafollicular cyst does a residual cyst, globulo-maxillary cyst and lateral periodontal cyst. Although over 750 cases of AOT were reported in the literature, clinicopathologic parameters of AOT in Koreans has not been investigated. 22 cases of AOT were retrieved from the files of the department of Oral Pathology, Seoul National University Dental Hospital and their clinicopathologic findings were reviewed. The central type accounts for 95%, 72% of which are follicular. The follicular and extrafollicular varients together are more commonly found in the maxilla than in the mandible with a ratio of 4.5:1. Age distribution showed that 59% of AOTs were diagnosed in the second decade of life, and mean age was 18.5 years. The female to male ratio was 3.4:1. All variants of AOT showed identical histologic features.

The p16 gene encodes an inhibitor of the cyclin-dependent kinase, which inactivates cyclin-dependent kinase and contro1s the cell cycle progression, The 10ss of p16 expression or overexpression has been reported in many kinds of tumors, Both p16 and PCNA regu1ates cell cycle progression at the Gl/8 checkpoint, Although many researches about the p16 expression in ora1 cancer have been carried out, there are few studies about the corre1ation between p16 ex pression and pro1iferation of ora1 cancer cells The object of this study was to eva1uate the avai1ability of p16 as ear1y diagnostic factor and prognostic factor through corre1atión ana1ysis of p16 expression in ora1 squamous cell carcinoma and its re1ation to PCNA index and clinicopatho1ogic factors 80 we investigated p16 immunohistochemica1 expression of 83 ora1 squmaous cell carcinomas, and obtained the resu1ts as followed, 18 out of the 83 cases(21, 69%) showed p16 positive and 65 samp1es(78,31%) showed p16 negative, Whi1e the mean va1ue of PCNA indices of p16 positive cases was 65,94 ::t 18,32, that of PCNA indices at p16 negati ve ones 54,79 ::t 18, 39, This difference between them showed statistica1 sígnificance, (P=O, 030) p16 positive group was 12/60(20, 0%) of well differentiated tumors and p16 negative group was 6/23(16, 1%) of moderate1y or poor1y differentiated tumors, This difference did not show statistica1 significance. (P=O. 372) From the resu1ts above, it was suggested p16 expression is re1ated to PCNA index in ora1 squamous cell carcinomas.

ReαlITent aphthous stomatitis (RAS) appears to be one of the most common oral diseases. However, the defmitive etiology of RAS is not well established, though many etiologic faαors have been suggested and examined. The present study was petformed to investigate the association between HIA and Korean recurrent aphthous stomatitis pa디ents. πle proportions of class 1 and class II HIA types expressed in 49 Korean subjects affected by recurrent aphthous stomatitis (RAS) and in 50 healthy controls were deteffi1Í11ed by microlymphocytotoxicity test. 까le sig띠ficance of the data was analyzed by chi-square test and Fisher' s exact test. πle proportions of HIA-Cw1 and -DR9 antigens were significantly higher in RAS pa디ents (p(0.05), whereas those of HIA-DR4 and -DQ2 antigens were significantly lower (p(0.05). 까le odds ratio (OR) were 2.8 for HIA-Cw1 and 2.7 for -DR9. πle etiologic fractions (EF) were 0.262 and 0.193, respectively. The results s맹gest that, in Koreans, there Í$ a sig띠ficant relation between HIA antigens and RAS. Genetic faαors ， reflected in the HIA type, may play an in1portant role in the development of RAS.