Lee Sam-Sun;Kang Beom-Hyun;Choi Hang-Moon;Jeon In-Seong;Heo Min-Suk;Choi Soon-Chul
Imaging Science in Dentistry
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v.30
no.4
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pp.275-279
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2000
Purpose: Radiation damage is produced and viable cell number is reduced. We need to know the type of cell death by the ionizing radiation and the amount and duration of cell cycle arrest. In this study, we want to identified the main cause of the cellular damage in the oral cancer cells and normal keratinocytes with clinically useful radiation dosage. Materials and Methods: Human gingival tissue specimens obtained from healthy volunteers were used for primary culture of the normal human oral keratinocytes (NHOK). Primary NHOK were prepared from separated epithelial tissue and maintained in keratinocyte growth medium containing 0.15 mM calcium and a supplementary growth factor bullet kit. Fadu and Hep-2 cell lines were obtained from KCLB. Cells were irradiated in a /sup 137/Cs γ-irradiator at the dose of 10 Gy. The dose rate was 5.38 Gy/min. The necrotic cell death was examined with Lactate Dehydrogenase (LDH) activity in the culture medium. Every 4 day after irradiation, LDH activities were read and compared control group. Cell cycle phase distribution and preG1-incidence after radiation were analyzed by flow cytometry using Propidium Iodine staining. Cell cycle analysis were carried out with a FAC Star plus flowcytometry (FACS, Becton Dickinson, USA) and DNA histograms were processed with CELLFIT software (Becton Dickinson, USA). Results: LDH activity increased in all of the experimental cells by the times. This pattern could be seen in the non-irradiated cells, and there was no difference between the non-irradiated cells and irradiated cells. We detected an induction of apoptosis after irradiation with a single dose of 10 Gy. The maximal rate of apoptosis ranged from 4.0% to 8.0% 4 days after irradiation. In all experimental cells, we detected G2/M arrest after irradiation with a single dose of 10 Gy. Yet there were differences in the number of G2/M arrested cells. The maximal rate of the G2/M ranges from 60.0% to 80.0% 24h after irradiation. There is no significant changes on the rate of the G0/G1 phase. Conclusion: Radiation sensitivity was not related with necrosis but cell cycle arrest and apoptosis. These data suggested that more arrested cell is correlated with more apoptosis.
Protein kinase C (PKC) is known to play a pivotal role in neoplastic transformation cells and its high expression is often found in a variety of types of tumors including oral cancer. While PKC is associated with the altered signal transduction pathway of the tumor cells, it is still unclear which isoform is involved in the carcinogenesis process. Since the cellular distributions and the roles of PKC are isoform-specific, it is very important to identify the specific target molecules to improve our understanding of the carcinogenesis processes. Thus, the present study attempted to perform chemical carcinogen-induced neoplastic transformation of human epithelial cells and analyze the specific isoform of PKCs involved in the cellular transformation. The study analyzed overall PKC responses upon MNNG(N-Methyl-N'-nitro-N-nitroso guanidine) exposure with [$^3H$] PDBu binding assay. PKC translocation was observed at high doses of MNNG treatment in the presence of extracellular calcium. Such effects were not observed in the absence of extracellular calcium. Translocational effects with exposure of MNNG was further enhanced in the presence of hydrocortisone. The result suggests that the type of PKC involved may be $Ca^{2+}$-dependent classical isoform and steroid hormone enhances PKC activation. Among cPKC isoforms examined, only $PKC-{\alpha}$ and r showed significant translocation of protein levels from cytosolic fraction to membrane fraction, as analyzed by immunoblot. $PKC-{\varepsilon}$ in nPKC class showed an inch·eased translocation, but other forms in this class did not show the effect. None of isoforms in aPKC class was affected by MNNG treatment. The study demonstrated that there was a certain specificity in the patterns of isoform induction follwong chemical carcinogen exposure and helped identify all the types of PKC isoforms expressed in human epithelial cells. It was revealed that PKC isoforms were activated in an early resonse to chemical carcinogen, suggesting that PKC be associated with carcinogenesis process from an early stage in this particular cell system. The study will contribute to improving our understanding of chemical-induced carcinogenesis in human cells and may provide a scientific basis to introduce the specific PKC inhibitors as an anticancer drug of epithelial cell-origin cancers including oral cancer.
The ultimate goal of periodontal therapy is directed to arresting the progression of the disease, and regenerating the fibrous attachment. In order to achieve such treatment aim, the plaque and calculus must be eliminated and the physiological conditions of the root surface must be changed to facilitate the attachment and migration of the new fibroblasts, The method of changing the proper root surface conditions to promote the healing of periodontal tissue involves mechanical procedures, such as scaling and root planing, and chemical procedures such as tetracycline-HCl. However, the formation of a long junctional epithelium was most frequently observed type of healing. Thus, the aim of this study was to examine in vitro the influence of surface conditioning of dentin by TC-HCl on human gingival epithelial cell attachment. Human gingival epithelial cells were obtained from healthy retromolar pad area(under the age 23 years). Seventy two teeth extracted from severe periodontitis were used as study material. To evaluate the epithelial cell attachment to dentin, the prepared specimen was divided to four groups. For the control group, only scaling and root planing were carried out, and for the test group, 1 to 3, the concentration of the TC-HCl was 50, 125 and 250mg/ml respectively. After cell cultivation time of 1-, 3-. 24 hour, for the indirect quantitative assessment of gingival epithelial cell attached to dentin sample, the absorbance of epithelial cell unattached to dentin was measured. The results were as follows; 1. There was no statistically significant difference between scaling and root planing group and TC-HCl 50mg/ml 125mg/ml and 250mg/ml group about absorbance of unattached epithelial cell to dentin sample(p>0.5). 2. As time passes, the absorbance of unattached gingival epithelial cell to dentin sample was decreased statistically significant(p<0.05). 3. There was no statistically significant difference among the TC-HCl group(p>0.05) We concluded that there was similar effect on gingival epithelial cell attachment between TC-HCl conditioning on root surface and only scaling and root planing treatment
The proto-oncogene bcl-2 confers a survival advantage to cells by blocking programmed cell death (apoptosis). Overexpression of bcl-2 probably plays a role in tumorigenesis, and the expression of the bcl-2 protein has been investigated in many kinds of tumors. An increased expression of nitric oxide synthetase(NOS) has been observed in human colon cancer cell lines as well as in human gynecological, breast, and CNS tumors. However there have been only a few reports on the expression of bcl-2 and $NOS_2$ in oral white lesions and cancer. The aim of this study was to investigate the relationship between the expression of Bcl-2 and $NOS_2$ and several pathological parameters such as histological types and layers. We reported desregulation of bcl-2 and $NOS_2$ expression during progression from oral white lesion, lichen planus and leukoplakia to squamous cell carcinoma. The obtained results were as follows: 1. Immunohistochemical analysis with monoclonal antibodies to bcl-2 oncoprotein and $NOS_2$ in formalin-fixed paraffin-embedded tissue sections revealed that bcl-2 expression is restricted to the basal cell layer and $NOS_2$ was mild expressed only in subepithelial inflammatory cells in normal human mucosa. There wasn't specific finding of those in lichen planus and leukoplakia. 2. Bcl-2 immunoreactivity in severe epithelial dysplasia or CIS occurs throughout the epithelium, $NOS_2$ reactivity in most superficial layer were noted. 3. In well-differentiated squamous cell carcinomas, mostly bcl-2 was overexpressed. In moderated and poor squamous cell carcinomas, the expression of $NOS_2$ was increased and that of bcl-2 was decreased. 4. The immunoreactivity of bcl-2 was 12.5% of normal mucosa, 30% of leukoplakia, 44% of lichen planus and 67% of carcinoma in situ. In carcinoma, those were 43%, 50% and 67% according to differentiation, respectively. 5. The immunoreactivity of $NOS_2$ was 25% of normal mucosa, 70% of leukoplakia, 78% of lichen planus and 100% of carcinoma in situ and epithelial dysplasia. In carcinoma, those were higher in moderated(100%) and poor(83%) squamous cell carcinomas than in well differentiated type(71%). 6. The expression of bcl-2 and $NOS_2$ by Western blot was increased highly in lichen planus and leukoplakia. Therefore, the expression of bcl-2 was increased in the white and precancerous lesions and that was decreased by differentiation of carcinoma. However, $NOS_2$ immunoreactivity in carcinoma in situ was lower than those in moderated and poor squamous cell. These findings suggest that the interaction of bcl-2 and $NOS_2$ may be roled importantly in growth and development of carcinoma.
Objectives : In this study, effects of haepyoijintang (HIJ) on the increase in airway epithelial mucosubstances of rats and ATP-, PMA-, EGF- or TNF-${\alpha}$-induced MUC5AC mucin production and gene expression from human airway epithelial cells were investigated. Methods : Hypersecretion of airway mucus was induced by exposure of rats to $SO_2$ during 3 weeks. Effect of orally-administered HIJ during 2 weeks on increase in airway epithelial mucosubstances from tracheal goblet cells of rats was evaluated using histopathological analysis after staining the epithelial tissue with PAS-alcian blue. Possible cytotoxicity of HIJ was evaluated by examining the potential damage of kidney and liver functions by measuring serum GOT/GPT activities and serum BUN and creatinine concentrations of rats and the body weight gain during experiment, after administering HIJ orally. At the same time, the effect of HIJ on ATP-, PMA-, EGF- or TNF-${\alpha}$-induced MUC5AC mucin production and gene expression from human airway epithelial cells (NCI-H292) were investigated. Confluent NCI-H292 cells were pretreated for 30 min in the presence of HIJ and treated with ATP ($200{\mu}M$), PMA (10 ng/ml), EGF (25 ng/ml) or TNF-${\alpha}$ (0.2 nM) for 24 hrs, to evaluate the effect of HIJ both on ATP-, PMA-, EGF- or TNF-${\alpha}$-induced MUC5AC mucin production using enzyme-linked immunosorbent assay (ELISA) and on gene expression by the same inducers using reverse transcription-polymerase chain reaction (RT-PCR). Results : (1) HIJ decreased the amount of intraepithelial mucosubstances of trachea of rats. (2) HIJ did not show renal and hepatic toxicities and did not affect body weight gain of rats during experiment. (3) HIJ significantly inhibited ATP-, PMA-, EGF-, and TNF-${\alpha}$-induced MUC5AC mucin productions from NCI-H292 cells. (4) HIJ significantly inhibited ATP-, PMA-, EGF-, and TNF-${\alpha}$-induced MUC5AC mucin gene expression from NCI-H292 cells. Conclusions : The result from the present study suggests that HIJ might control the production and gene expression of airway mucin observed in various respiratory diseases accompanied by mucus hypersecretion and do not show in vivo toxicity to liver and kidney functions after oral administration. Effect of HIJ with their diverse components should be further investigated using animal experimental models that can reflect the pathophysiology of airway diseases through future studies.
Journal of the Korean Association of Oral and Maxillofacial Surgeons
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v.33
no.3
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pp.247-255
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2007
The bone morphogenic protein(BMP) can promote migration and growth of mesenchymal cells and initiate process for bone and cartilage formation. Cartilage-derived morphogenic protein(CDMP)-1 and -2 belong to the bone morphogenetic protein family in the transforming growth factor(TGF)-${\beta}$ superfamily. Although pleomorphic adenoma of the salivary glands is an epithelial tumor, it frequently shows ectopic cartilaginous formation with biomolecular studies. The mechanism of pathogenesis in cartilaginous formation is still controversy. We examined the expression and localization of CDMP-1 and -2, in comparison with the localization of cartilaginous matrix proteins, in human normal salivary glands and 20 cases of pleomorphic adenoma using immunohistochemical methods. The results were followed. 1. CMP-1 was immunolocalized in the striated ducts and the intercalated ducts, but not expressed in excretory duct, CDMP-2 was not expressed in the normal salivary glands. 2. CMP-1 was immunolocalized in the ductal cell and cuboidal neoplastic myoepithelial cells around the chondroid areas of the pleomorphic adenomas, whereas these molecules were not localized in the spindle-shaped neoplastic myoepithelial cells of the myxoid element in these tumors. CDMP-2 was expressed neither in normal salivary glands nor in any elements of the pleomorphic adenomas. 3. In transmission electron microscopic view, the tumor cells are composed of modifed myoepithelial cells between hyaline and myxoid stroma. 4. In Immuno-blot analysis, strong overexpression of CDMP-1 was frequently seen in pleomorphic adenomas, but the level of CDMP-2 was expressed minimally in pleomorphic adenoma. From the these results, it should be suggested that undifferentiated neoplastic myoepithelial cells around the chondroid areas expressed CDMP-1 and suggested that this molecule may play a role in the differentiation of neoplastic myoepithelial cells in pleomorphic adenoma, but not CDMP-2.
Human malignant melanoma is an aggressive skin cancer which has been rising at a greater rate than any other cancers. Although various new therapeutic methods have been developed in previous studies, this disease has properties of high proliferation and metastasis rate which remain obstacles that have lead to a poor prognosis in patients. It has been reported that a specific Lactobacillus extract has anti-cancer and -metastasis effect in vitro and in vivo. However, previous research has not specified precisely what effect the Lactobacillus rhamnosus GG (LGG) extract has had on human malignant melanomas. In this study, we showed that the LGG extract has anti-cancer and -metastasis effects on the human malignant melanoma cell lines, A375P and A375SM. At first, it was found that, while the LGG extract affects human neonatal dermal fibroblasts slightly, it induced the dose-dependent anti-cancer effect on A375P and A375SM by a WST-1 proliferation assay. As a result of a real-time PCR analysis, the expression patterns of several genes related to cell cycle, proliferation, and apoptosis were modulating in a manner that inhibited the growth of both malignant melanoma cell lines after the treatment of the LGG extract. Furthermore, genes related to the epithelial-mesenchymal transition were down-regulated, and migration rates were also decreased significantly by the LGG extract. Our study showed that the LGG extract could be used as a potential therapeutic source.
Song, Zi Hae;Cho, Kyung Hwa;Kim, Jin Young;Lee, Hoi Young
Journal of dental hygiene science
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v.19
no.2
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pp.141-146
/
2019
Background: Oral cancer has a high incidence worldwide and has been closely associated with smoking, alcohol, and infection by the human papillomavirus. Metastasis is highly important for oral cancer survival. Lysophosphatidic acid (LPA) is a bioactive lipid mediator that promotes various cellular processes, including cell survival, proliferation, metastasis, and invasion. Signal transducer and activator of transcription (STATs) are transcription factors that mediate gene expression. Among the seven types of STATs in mammals, STAT3 is involved in invasion and metastasis of numerous tumors. However, little is known about the role of STAT3 in oral tumor invasion. In the present study, we hypothesized that STAT3 mediates LPA-induced oral cancer invasion. Methods: Immunoblotting was performed to analyze LPA-induced STAT3 activation. 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was performed to assess the survival rates of YD-10B cells. STAT3 levels in LPA-treated oral tumor cells were evaluated by performing in vitro invasion assay. Results: To the best of our knowledge, this is the first study to demonstrate that LPA enhances STAT3 phosphorylation in oral cancer. In addition, treatment with WP1066, a selective inhibitor of STAT3, at a concentration that does not cause severe reduction in cell viability, significantly attenuated LPA-induced YD-10B cancer cell invasion. Conclusion: The results suggested that LPA induces oral tumor cells with greater invasive potential via STAT3 activation. Our findings provided important insights into the mechanisms underlying mouth neoplasms.
Pleomorphic adenoma is the most common benign tumor in salivary glands, and occurred in frequency of 60% in parotid gland tumors, and 50% in submandibular gland tumors, and 25% in sublingual gland tumors. Histopathologically, pleomorphic adenoma is composed of epithelial cells and mesenchymal tissues, and called 'mixed tumor' because of morphological divergency. The cell structures of luminal area are composed of polyhedral and cuboidal secretory epithelial cells and modified myoepithelial cells around it, and mesenchymal tissue is composed of some myoepithelial cells and stromal tissue. In stromal tissue, myxoid change, chondroid change, or hyalinization can be seen even if bone tissue. In many studies, tumor cells of pleomorphic adenoma containing modified myoepithelial cell participate in synthesis of glycosaminoglycans. In this study, tissue sample of pleomorphic adenoma of human salivary gland were obtained from 20 surgical specimens, and all specimens were routinely fixed in 10% formalin and embedded. Serial 4-8${\mu}m$ thick sections were cut from paraffin blocks. The histopathologic evaluation was done with light microscopy. And, with immunohistochemical staining, characteristics of glycosaminoglycan were observed. And, for biochemical analysis of glycosaminoglycan, isolation of crude glycosaminoglycan from tumor tissue and immuno-blot analysis were carried out. With transmission electromicroscopy, tumor cells and biologic behavior of pleomorphic adenoma were observed with distribution and expression of glycosaminoglycan in tumor cells, The results were obtained as follows: 1. In immunohistochemical study, chondroitin 4-sulfate is highly postively stained in myxoid stromal tissue, and chondroitin 6-sulfate is highly positively stained in chondroid mesenchymal tissue, both glycosaminoglycans are positively stained in non-luminal cell of ductal area. 2. Dermatan sulfate and keratan sulfate is positively stained in periductal non-luminal tumor cells. 3. In immunohistochemical study, heparan sulfate is weakly stained in luminal cells and non-luminal cells around duct, and chondroid mesenchymal tissue. 4. In transmission electromicroscopic view, the tumor cells are composed of modified myoepithelial cells, and contain many microfilaments and well developed rough endoplasmic reticulum. 5. In Immuno-Blot analysis, the expression of glycosaminoglycans is expressed mostly in chondroitin 6-sulfate and chondroitin 4-sulfate. From the results obtained in this study, tumor cells of pleomorphic adenoma are composed of modified myoepithelial cells, and glycosaminoglycans of chondroitin 4-sulfate and chondroitin 6-sulfate mostly participate in the development of pleomorphic adenoma, but dermatan sulfate, keratan sulfate and heparan sulfate glycosaminoglycans were expressed variably.
Patients with head and neck cancer are treated with therapeutic irradiation, which can result in irreversible salivary gland dysfunction. Because there is no complete cure for such patients, stem cell therapy is an emerging alternative for functional restoration of salivary glands. In this study, we investigated in vitro characteristics of primarily isolated epithelial cells from human salivary gland (Epi-SGs) and in vivo formation of acini-like structures by Epi-SGs. Primarily isolated Epi-SGs showed typical epithelial cell-like morphology and expressed E-cadherin but not N-cadherin. Epi-SGs expressed epithelial stem cell (EpiSC) and embryonic stem cell (ESC) markers. During long-term culture, the expression of EpiSC and ESC markers was highly detected and maintained within the core population with small size and low cytoplasmic complexity. The core population expressed cytokeratin 7 and cytokeratin 14, known as duct markers indicating that Epi-SGs might be originated from the duct. When Epi-SGs were transplanted in vivo with Matrigel, acini-like structures were readily formed at 4 days after transplantation and they were maintained at 7 days after transplantation. Taken together, our data suggested that Epi-SGs might contain stem cells which were positive for EpiSC and ESC markers, and Epi-SGs might contribute to the regeneration of acini-like structures in vivo. We expect that Epi-SGs will be useful source for the functional restoration of damaged salivary gland.
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