• Journal of Oral Medicine and Pain
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• v.34 no.3
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• pp.261-276
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• 2009

Lactacystin, a microbial natural product synthesized by Streptomyces, has been commonly used as a selective proteasome inhibitor in many studies. Proteasome inhibitors is known to be preventing the proliferation of cancer cells in vivo as well as in vitro. Furthermore, proteasome inhibitors, as single or combined with other anticancer agents, are suggested as a new class of potential anticancer agents. This study was undertaken to examine in vitro effects of cytotoxicity and growth inhibition, and the molecular mechanism underlying induction of apoptosis in SCC25 human tongue sqaumous cell carcinoma cell line treated with lactacystin. The viability of SCC25 cells, human normal keratinocytes (HaCaT cells) and human gingiva fibroblasts (HGF-1 cells), and the growth inhibition of SCC25 cells were assessed by MTT assay and clonogenic assay respectively. The hoechst staining, hemacolor staining and TUNEL staining were conducted to observe SCC25 cells undergoing apoptosis. SCC25 cells were treated with lactacystin, and Western blotting, immunocytochemistry, confocal microscopy, FAScan flow cytometry, MMP activity, and proteasome activity were performed. Lactacystin treatment of SCC25 cells resulted in a time- and does-dependent decrease of cell viability and a does-dependent inhibition of cell growth, and induced apoptotic cell death. Interestingly, lactacytin remarkably revealed cytotoxicity in SCC25 cells but not normal cells. And tested SCC25 cells showed several lines of apoptotic manifestation such as nuclear condensation, DNA fragmentation, the reduction of MMP and proteasome activity, the decrease of DNA contents, the release of cytochrome c into cytosol, the translocation of AIF and DFF40 (CAD) onto nuclei, the up-regulation of Bax, and the activation of caspase-7, caspase-3, PARP, lamin A/C and DFF45 (ICAD). Flow cytometric analysis revealed that lactacystin resulted in G1 arrest in cell cycle progression which was associated with up-regulation in the protein expression of CDK inhibitors, $p21^{WAF1/CIP1}$ and $p27^{KIP1}$. We presented data indicating that lactacystin induces G1 cell cycle arrest and apoptois via proteasome, mitochondria and caspase pathway in SCC25 cells. Therefore our data provide the possibility that lactacystin could be as a novel therapeutic strategy for human tongue squamous cell carcinoma.

• Tuberculosis and Respiratory Diseases
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• v.59 no.6
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• pp.631-637
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• 2005

Background : Transcriptional factors of the CREB(cAMP Response Element Binding Protein) are involved in the regulation of gene expression in response to a variety of signaling pathways. Proteins produced by the CREB genes play key roles in many physiological processes, including memory and long-term potentiation. The retinoic acid receptor (RAR) axis mediates epithelial cell differentiation and proliferation in many tissues including the lung. Material and method : The RAR and CREB expression levels were examined in 60 adenocarcinomas and 60 squamous cell carcinomas of the lung using immunohistochemical staining. Results : 1) RAR protein expression was found in 58.3%(35/60) of adenocarcinomas and 36.7%(22/60) of squamous cell carcinomas(P<0.05). 2) RAR protein expression was found in 80%(16/20) of well differentiated adenocarcinomas, 60%(12/20) of moderately differentiated adenocarcinomas, and 35%(7/20) of poorly differentiated adenocarcinomas (P<0.01). 3) RAR protein expression was found in 45%(9/20) of well differentiated squamous cell carcinomas, 35%(7/20) of moderately differentiated squamous cell carcinomas, and 30%(6/20) of poorly differentiated squamous cell carcinomas (P>0.05). 4) CREB expression was found in 61.7%(37/60) of adenocarcinomas and 40%(24/60) of squamous cell carcinomas( P<0.05). 5) CREB expression was found in 85%(17/20) of well differentiated adenocarcinomas, 60%(12/20) of moderately differentiated adenocarcinomas, and 40%(8/20) of poorly differentiated adenocarcinomas (P<0.01). 6) CREB expression was found in 45%(9/20) of well differentiated squamous cell carcinomas, 35%(7/20) of moderately differentiated squamous cell carcinomas, and 35%(8/20) of poorly differentiated squamous cell carcinomas(P>0.05). 7) RAR and CREB expression was found in 68.5% of lung cancers, and there was a significant correlation between them(P<0.05). Conclusion : RAR and CREB expression can be used to indirectly determine the malignant potentiality of a cell.

• Journal of Chest Surgery
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• v.39 no.1 s.258
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• pp.1-11
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• 2006

Background: CD44 is a glycoprotein on the cell surface which is involved in the cell-to-cell and cell-to-matrix interaction. The standard form, CD44s and multiple isoforms are determined by alternative splicing of 10 exons. Recent studies have suggested that CD44 may help invasion and metastasis of various epithelial tumors as well as activation of Iymphocytes and monocytes. The expression pattern of CD44 can be different according to tumor types. The author studied the expression pattern of CD44s and one of its variants, CD44v6 in non-small cell lung carcinomas (NSCLC) to find their implications on clinicopathologic aspects, including the survival of the patients. Material and Method: A total of 89 primary NSCLSs (48 squamous cell carcinomas, 33 adenocarcinomas, and 8 undifferentiated large cell carcinomas) were retrieved during the years between 1985 to 1994. The immunohisto chemistry was done by using monoclonal antibodies and the CD44 expression for angiogenesis was evaluated by counting the number of tumor microvessels. Result: Seventy-one (79.8$\%$) and 64 (71 .9$\%$) among 89 NSCLSs revealed the expression of CD44s and CD44v6, respectively. The expression of CD44s was well correlated with that of CD44v6 (r=0.710, p < 0.0001). The expression of CD44s and CD44v6 was associated with the histopathologic type of the NSCLCs, and squamous cell carcinoma was the type that showed the highest expression of CD44s and CD44v6 (p < 0.0001). Microvessel count was the highest in adenocarcinomas (113.6$\pm$69.7 on 200-fold magnification and 54.8$\pm$41.1 on 400-fold magnification) and correlated with the tumor size of TNM system (r=0.217, p=0.043) and CD44s expression (r=0.218, p=0.040). In adenocarcinoma, the patients with higher CD44s expression survived shorter than those with lower CD44s expression (p=0.0194) but there was no statistical significance on multivariate analysis(p=0.3298). Conclusion: The expression of both CD44s and CD44v6 may be associated with the squamous differentiation in non-small cell lung carcinomas. The relationship of CD44s expression with micro-vessel density of the tumor suggests an involvement of CD44s in tumor angiogenesis, which in turn would help tumor growth.

• The Korean Journal of Cytopathology
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• v.7 no.1
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• pp.88-91
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• 1996

A primary squamous cell carcinoma of the breast was evaluated by fine needle aspiration cytology in a 60 year-old female. Squamous cell carcinoma is a rarely encountered lesion in the breast and nine cases of cytologic findings of mammary squamous cell carcinoma have been reported in the world literature. Our case appears to be one of these rare pure squamous cell tumors. The cytologic diagnosis was possible because of the well defined characteristics of the malignant squamous cells, similar to those found in other locations. Thorough examination of the patient did not reveal squamous cell carcinoma elsewhere.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.2
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• pp.165-169
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• 2004

Pleomorphic adenoma is the most common neoplasm of the parotid gland, generally presenting as a slowly growing, firm, well-circumscribed, painless nodule. It is often difficult to separate into benign and malignant categories because its bland histomorphologic and cytologic features. This tumor can be rarely associated with cystic change, hemorrhagic necrosis, or spontaneous infarction. Necrosis of lesional tissue may be associated with malignant transformation, particularly in a pleomorphic adenoma. We report a case of 50-year-old woman presented with a enlarging right parotid mass. Computed tomographic scan demonstrated a right superficial lobe mass with ill-defined border. The preoperative fine needle aspiration yielded necrotic debris and atypical squamous elements that were thought to be compatible with high degree of mucoepidermoid carcinoma. A total parotidectomy with intraoperative frozen section revealed extensive necrosis and diagnosed as malignant tumor. This tumor was finally diagnosed as a pleomorphic adenoma with necrosis on permanent sections. Caution should be exercised in evaluation of the parotid neoplasms with central necrosis to avoid misdiagnosis of such lesions as malignancy.

• Korean Journal of Clinical Laboratory Science
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• v.37 no.3
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• pp.197-206
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• 2005

To determine the correlation between mast cells(MCs) and neoangiogenesis in the growth and progression of cervical cancer, we investigated mast cell density(MCD), microvessel density(MVD) and the expression of vascular epithelial growth factor(VEGF) in cervical intraepithelial neoplasia and invasive suqamous cell carcinoma of the uterine cervix. Forty-five cervical intraepithelial neoplasia(CIN I, II and III), 15 microinvasive carcinomas, 15 invasive squamous cell carcinomas and 20 normal cervical epithelia were included in this study. MCs were stained with anti-c-Kit antibody and alcian blue, microvessels with anti-factor VIII antibody and VEGF with anti-VEGF antibody. The adjacent fields of both normal and neoplastic epithelium were used for counting MCs and microvessels. Computerized image analysis was used to evaluate MCD and MVD. MCD and MVD were the mean numbers per $1mm^2$ counted in 5-10 high and low power fields respectively. In both c-Kit and alcian blue stained sections, MCD progressively increased along the continuum from CIN I to invasive squamous cell carcinoma(p<0.001). MVD increased significantly with cervical neoplasia progression, from CIN to invasive squamous cell carcinoma (p<0.001). In double c-Kit and Factor VIII-stained sections, MCs were mainly present in the areas adjacent to newly formed blood vessels. However, there were no significant differences in MCD and MVD between normal epithelum and CIN I. A strong correlation was also observed between MCD and MVD. In double VEGF and alcian blue-stained sections, VEGF was expressed in only MCs. Strong VEGF-positive MCs were particularly abundant around the tumorous region. Our results suggest that MCs may upregulate neoangiogenesis by VGEF secretion in the development and progression of cervical neoplasia.

• Journal of Chest Surgery
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• v.35 no.12
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• pp.902-905
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• 2002

Pulmonary resection often leaves a pleural space problem that can cause prolonged air leaks. We describe a patient with lung cancer undergoing a right middle and lower lobectomy complicated by prolonged air leaks. He had a history of pulmonary tuberculosis and COPD. Artificial pneumoperitoneum was made by instillation of air via a small central vein catheter into the left lower quadrant on postoperative day(POD) 21. The air leak ceased on POD 23 and the chest tube was removed on POD 25.

• Journal of Life Science
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• v.29 no.3
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• pp.295-302
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• 2019

Liquiritigenin (LG) is a chiral flavonoid isolated from the roots of licorice. It exhibits multiple biological activities including anti-oxidant, anti-cancer, and anti-inflammatory effects. In particular though, the anti-cancer activity of LG in oral squamous cell carcinoma has yet to be elucidated, and LG-induced apoptosis in oral squamous cell carcinoma remains poorly understood. In the present study, we tested the role of LG in inducing apoptosis in oral squamous cell carcinoma cells. LG treatment of HN22 cells resulted in a dose-dependent inhibition of cell viability as detected by a 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide assay. The induction of apoptosis in terms of Annexin V/7-Aminoactinomycin D staining, sub-G1 population, and multi-caspase activity were assessed with a $Muse^{TM}$ Cell Analyzer. Flow cytometric analysis revealed that LG treatment resulted in G2/M arrest in cell cycle progression and downregulation of cyclin B1 and CDC2 expression in a concentration-dependent manner. It also resulted in significant upregulation of p27. In addition, LG was seen to trigger the generation of reactive oxygen species and induce CCAAT/enhancer-binding protein homologous protein and 78-kDa glucose-regulated protein in concentration-dependent upregulation. The LG treatment of HN22 cells led to a loss of mitochondrial membrane potential (${\Delta}{\Psi}m$); it also reduced the levels of anti-apoptotic protein and increased the expression of apoptotic protease activating factor-1, cleaved poly (ADP-ribose)polymerase and Bax. Overall, our results indicate that the pro-apoptotic effects of LG in HN22 cells depend on the activation of both intrinsic and extrinsic signaling pathways. Thus, our results suggest that LG constitutes a natural compound with a potential role as an anti-tumor agent in oral squamous cell carcinoma.

• Tuberculosis and Respiratory Diseases
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• v.64 no.1
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• pp.15-21
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• 2008

Background: The melanoma antigen-encoding (MAGE) genes are known to be expressed in various cancer cells, including non-small cell lung cancer (NSCLC), and are silent in all normal tissues except for the testis. In patients with peripheral NSCLC, bronchial washing fluid can be used to detect the MAGE genes, suggesting a diagnosis of lung cancer. In order to evaluate the diagnostic utility of the MAGE test in patients with peripheral NSCLC, bronchial washing fluid was investigated in patients with peripheral pulmonary nodules, which were invisible as detected by bronchoscopy. Methods: Bronchial washing fluid from 37 patients was used for cytological examinations and MAGE gene detection, using RT-nested-PCR of common A1-A6 mRNA. Results were compared to a final diagnosis of patients as confirmed by pathology. Results: Among the 37 subjects, NSCLC was diagnosed in 21 patients, and benign pulmonary diseases were diagnosed in 16 patients. MAGE mRNA was detected in 10 of 21 (47.6%) NSCLC patients, while conventional cytology examinations were positive for MAGE expression in 2 of 21 (9.5%) cases. MAGE expression was observed in 4 of 16 (25%) benign pulmonary disease patients. Conclusion: The MAGE test of bronchial washing fluid can be used as a sensitive predictor of peripheral NSCLC patients.

• Journal of Life Science
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• v.19 no.8
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• pp.1047-1054
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• 2009

Oral squamous carcinoma (OSC) cells present resistance to chemotherapeutic agents-mediated apoptosis in the late stages of malignancy. Advances in the understanding of bacterial toxins have produced new strategies for the treatment of cancers. It was demonstrated here that Pseudomonas aeruginosa exotoxin A (PEA) significantly decreased the viability of chemoresistant YD-9 cells in the apoptosis mechanism. Apoptotic manifestations were evident through changes in nuclear morphology and generation of DNA fragmentation. PEA treatment induced caspase-3, -6 and -9 cleavage, and activation. These events preceded proteolysis of the caspase substrates poly (ADP-ribose) polymerase (PARP), DNA fragmentation factor 45 (DFF45), and lamin A in YD-9 cells. The reduction of mitochondrial membrane potential, release of cytochrome c and SmacjDlABLO from mitochondria to cytosol, andtranslocation of AlF into nucleus were shown. While p53, p21 and $14-3-3{\gamma}$ were upregulated, cyclin Band cdc2 were downregulated by PEA treatment. Taken together, PEA induces apoptosis in chemoresistant YD-9 cells via activation of caspases, mitochondrial events and regulation of cell cycle genes.