- Email: [email protected]
Poster 063: The Effects of Retinoic Acid on Differentiation of Follicular Ameloblastoma-Derived Cells
Scientific Poster Session tumor location (p⫽0.3397) and grade (p⫽0.3958) were not associated with recurrence. Histologic subtype was suggestive of recurrence (p⫽0.0776). Advancing T stage (p⫽0.0003) and tumors requiring multimodality treatment (p⬍.0001) were statistically significant predictors of recurrence. Conclusion: The overall recurrence for this study population was 21.8%. While histologic subtype was suggestive of recurrence, extent of local disease and the need for postoperative adjuvant therapy were predictors of recurrence. Tumors amenable to surgical extirpation were the least recurrent. Therefore surgery is an essential component in the initial treatment of minor salivary gland malignancies and offers the most durable chance of cure in tumors amenable to resection. References Yih, Wei-Yung et al. Intraoral minor salivary gland neoplasms: review of 213 cases. Journal of Oral & Maxillofacial Surgery 63(6):805-10, 2005 Jun Jansisyanont P, Blanchaert RH Jr, Ord RA. Intraoral minor salivary gland neoplasm: a single institution experience of 80 cases. Int J Oral Maxillofac Surg 2002 Jun;31(3):257-61
POSTER 062 Comparison of Reliability of the Vital Staining With Iodine and Toluidine Blue Solutions to Detect and Delineate Oral Epithelial Dysplasia and Carcinoma Masayuki Takano, DDS, PhD, 2-9-28 Misakicho, Chiyoda-ku, Tokyo, 101-0061, Japan (Kakizawa T; Takasaki Y; Takaku Y; Seta S; Kuwayama M; Imai T; Matsuzaka K; Hashimoto S) Statement of the Problem: Some kind of oral leukoplakias progressed to malignancy a few months or years later, suggesting the importance of correct diagnosis and treatment of these lesions from the standpoint of early detection and prevention of oral cancers. We have used the vital staining test with iodine (modified Lugol’s iodine solution) and toluidine blue (TB) solutions to detect and delineate cancerous lesions of oral mucosa as an adjunct diagnosis. Object: The iodine staining method is used a lot in Japan, but in Europe and the United States, the TB staining test has been generally used. The purpose of this study is to compare the reliability of vital staining tests with iodine and TB solutions for detection and delineation of oral epithelial dysplasia and carcinoma. Materials and Methods: The study included 58 patients with oral precancer or malignant-suspicious lesion attending OMFS, Suidobashi Hospital, Tokyo Dental College from January 2000 to December 2006. Each of these patients took staining tests with 3% iodine and 0.5% TB solutions before surgical resection. The resected 43.e36
specimens were investigated histopathologically after operation. Method of Data Analysis: The results of the clinical and histologic diagnoses and the staining results were compared. The sensitivity, specificity, and the positive and negative predictive results were calculated. Results: The result shows that sensitivity of iodine staining test was 77.3%, and that of TB staining was 91.2%. On the other hand, specificity of each staining test was 52.8% and 67.6%. Almost low-grade epithelial dysplasia showed only iodine-unstained area, but malignant lesions tended to accompany TB-positive part. Conclusion: We conclude that both iodine staining and TB staining is useful to detect oral carcinoma and epithelial dysplasia at the high rate. The iodine solution is useful to delineate dysplastic epithelium as unstained area, and TB-positive indicates that a malignant lesion is developing. References Yajima Y, Takano M. et al. Quantification of telomerase activity of regions unstained with iodine solution that surround oral squamous cell carcinoma. Oral oncology, 40, 314-320, 2004 Epstein JB, Zhang L, et al. Increased allelic loss in toluidine bluepositive oral premalignant lesions. Oral surgery Oral medicine Oral pathology, 95, 45-50, Jan 2003 Onofre MA, Sposto M, Claudia Nabarro M. Reliability of toluidine blue application in the detection of oralepithelial dysplasia and in situ andinvasive squamous cellcarcinomas. Oral surgery Oral medicine Oral pathology, 91, 535-540, May 2001
POSTER 063 The Effects of Retinoic Acid on Differentiation of Follicular Ameloblastoma-Derived Cells Aki Takekita, DDS, Japan (Yamamoto H) Statement of the Problem: Whether the addition of retinoic acid induces the differentiation of follicular ameloblastoma-derived cells was investigated by RT-PCR and protein analysis using a microarray. Materials and Methods: Retinoic acid was added to a primary culture of follicular ameloblastoma, and its effect was investigated by RT-PCR and protein analysis using a microarray. The study was approved by the Osaka Dental University Ethics Committee (Osakairin No. 060926). Method of Data Analysis: Its effect was investigated by RT-PCR and protein analysis using a microarray. Results: Primary culture of follicular ameloblastomaderived cells led to the formation of colonies like the pavement. RT-PCR detected the elevation of amelogen and enamelin expressions in the retinoic acid-treated group. On protein analysis using the microarray, exAAOMS • 2007
Scientific Poster Session pressions of NEK, Csk, Cdk4, and Fnk related to proliferation, TRADD and TNF␣ related to differentiation apoptosis, and tyrosine phosphatase were increased, whereas expressions of PLC, Ras, and PKC were inhibited. Conclusion: A close involvement of retinoic acid in the differentiation of ameloblastoma-derived cells to ameloblast-like cells was suggested. References Jernvall J and Thesleff I. Reiterative signaling and patterning during mammalian tooth morphogenesis. Mechanisms of Development 2000; 92:19-29 K. Heikinheimo, K.J. Jee, T. Niini, Y. Aalto, R.-P. Happonen, I. Leivo, and S. Knuutila. Gene Expression Profiling of Ameloblastoma and Human Tooth Germ by Means of a cDNA Microarray. J. Dent. Res 2002; 81:525-530
POSTER 064 Molecular Mechanisms of Hypoxic Response in Head and Neck Squamous Cell Carcinoma Hiroyuki Mizuuchi, DDS, PhD, Japan (Nishiyama M; Mizuuchi H; Yoshiga K) Statement of the Problem: Tumor hypoxia is now recognized as a key determinant of the biologically aggressive malignant phenotype and the therapeutic resistance. Therefore, better understandings of molecular mechanisms of hypoxic response in solid tumors, including head and neck squamous cell carcinoma (HNSCC), may provide improvement of patients’ prognosis. Hypoxia-inducible factor-1 (HIF-1), the key transcription factor under hypoxic conditions, controls a variety of genes, but its detailed functional mechanisms and hypoxia-inducible downstream genes remain unclear in HNSCC. In this study, we tried to clarify the roles of HIF-1 in hypoxic response and identify novel hypoxia inducible genes in HNSCC cell lines. Materials and Methods: Seven HNSCC cell lines, HSC2, HSC3, HSC4, Ca9-22, KOSC2, HO-1-N-1, HO-1u-1, and KB, were obtained from The Japanese Cancer Research Resource Bank. These cell lines were incubated under normoxic (21% pO2) or hypoxic (1% pO2) conditions for 8-24 hours in experiments. HIF-1␣ protein levels and HIF-1 transcription activities were evaluated by immunoblotting analysis using antiHIF-1␣ antibody and transient transfection with hypoxia response element (HRE)-luciferase reporter plasmid and luciferase assays, respectively. Oligomicroarray and real-time RT-PCR were performed for gene expression analyses. Chemosensitivities were evaluated by MTT assays. AAOMS • 2007
Method of Data Analysis: Statistical analyses were performed by student t test or Mann-Whitney U test. Results: We first compared protein expression levels of HIF-1␣ among 7 HNSCC cell lines. The immunoblottings revealed that hypoxic treatment (1% pO2 for 8 hours) drastically increased HIF-1␣ protein in most cell lines but the inductions varied among cell lines. Subsequently, HIF-1 transcription activities in cell lines were evaluated and results demonstrated that hypoxia-induced HIF-1 activity was strongest in HSC2 cells but weakest in Ca9-22 cells. In HSC2, HIF-1␣ proteins were induced most when the cell was cultured under 1-0.1% pO2 conditions. MTT assays showed that sensitivities of HSC2 to 5-FU or CDDP significantly decreased in hypoxic condition. We next performed comprehensive gene expression analyses using an oligonucleotide array (19,881 probes), which demonstrated that 24-hour hypoxic treatment up-regulated 2,638 genes in HSC-2. The upregulated genes in HSC2 included many novel hypoxia-inducible genes, and 4 genes were evaluated for their expression levels in esophageal cancer tissue specimens by real-time RT-PCR. Among them, 3 genes appeared to show significantly higher expression in tumor tissues than in normal ones. Conclusion: We demonstrated that hypoxia significantly induced HIF-1 activity in HIF-1␣ expressing HNSCC cell lines, which strongly affected cell chemosensitivities. We also identified several novel hypoxia inducible genes, which might play some important role in tumor tissues. Further investigations of their functional mechanisms may provide novel diagnostic markers or therapeutic targets of HNSCC. References Carcinogenesis 2003; 24: 1779-1783 Journal of Biological Chemistry 2003; 278: 6816-6823 The EMBO journal 2000; 19: 4298-4309
POSTER 065 Screening of DNA Copy Number Alterations Detected in Oral Squamous Cell Carcinomas Using Array-Based Comparative Genomic Hybridization Kenichiro Uchida, DDS, PhD, Department of Oral and Maxillofacial Surgery, Yamaguchi University School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi, 7558505, Japan (Okafuji M; Mihara M; Mano T; Ueyama Y; Sasaki K) Statement of the Problem: It is widely accepted that various carcinomas, including oral squamous cell carci43.e37
POSTER 062 Comparison of Reliability of the Vital Staining With Iodine and Toluidine Blue Solutions to Detect and Delineate Oral Epithelial Dysplasia and Carcinoma Masayuki Takano, DDS, PhD, 2-9-28 Misakicho, Chiyoda-ku, Tokyo, 101-0061, Japan (Kakizawa T; Takasaki Y; Takaku Y; Seta S; Kuwayama M; Imai T; Matsuzaka K; Hashimoto S) Statement of the Problem: Some kind of oral leukoplakias progressed to malignancy a few months or years later, suggesting the importance of correct diagnosis and treatment of these lesions from the standpoint of early detection and prevention of oral cancers. We have used the vital staining test with iodine (modified Lugol’s iodine solution) and toluidine blue (TB) solutions to detect and delineate cancerous lesions of oral mucosa as an adjunct diagnosis. Object: The iodine staining method is used a lot in Japan, but in Europe and the United States, the TB staining test has been generally used. The purpose of this study is to compare the reliability of vital staining tests with iodine and TB solutions for detection and delineation of oral epithelial dysplasia and carcinoma. Materials and Methods: The study included 58 patients with oral precancer or malignant-suspicious lesion attending OMFS, Suidobashi Hospital, Tokyo Dental College from January 2000 to December 2006. Each of these patients took staining tests with 3% iodine and 0.5% TB solutions before surgical resection. The resected 43.e36
specimens were investigated histopathologically after operation. Method of Data Analysis: The results of the clinical and histologic diagnoses and the staining results were compared. The sensitivity, specificity, and the positive and negative predictive results were calculated. Results: The result shows that sensitivity of iodine staining test was 77.3%, and that of TB staining was 91.2%. On the other hand, specificity of each staining test was 52.8% and 67.6%. Almost low-grade epithelial dysplasia showed only iodine-unstained area, but malignant lesions tended to accompany TB-positive part. Conclusion: We conclude that both iodine staining and TB staining is useful to detect oral carcinoma and epithelial dysplasia at the high rate. The iodine solution is useful to delineate dysplastic epithelium as unstained area, and TB-positive indicates that a malignant lesion is developing. References Yajima Y, Takano M. et al. Quantification of telomerase activity of regions unstained with iodine solution that surround oral squamous cell carcinoma. Oral oncology, 40, 314-320, 2004 Epstein JB, Zhang L, et al. Increased allelic loss in toluidine bluepositive oral premalignant lesions. Oral surgery Oral medicine Oral pathology, 95, 45-50, Jan 2003 Onofre MA, Sposto M, Claudia Nabarro M. Reliability of toluidine blue application in the detection of oralepithelial dysplasia and in situ andinvasive squamous cellcarcinomas. Oral surgery Oral medicine Oral pathology, 91, 535-540, May 2001
POSTER 063 The Effects of Retinoic Acid on Differentiation of Follicular Ameloblastoma-Derived Cells Aki Takekita, DDS, Japan (Yamamoto H) Statement of the Problem: Whether the addition of retinoic acid induces the differentiation of follicular ameloblastoma-derived cells was investigated by RT-PCR and protein analysis using a microarray. Materials and Methods: Retinoic acid was added to a primary culture of follicular ameloblastoma, and its effect was investigated by RT-PCR and protein analysis using a microarray. The study was approved by the Osaka Dental University Ethics Committee (Osakairin No. 060926). Method of Data Analysis: Its effect was investigated by RT-PCR and protein analysis using a microarray. Results: Primary culture of follicular ameloblastomaderived cells led to the formation of colonies like the pavement. RT-PCR detected the elevation of amelogen and enamelin expressions in the retinoic acid-treated group. On protein analysis using the microarray, exAAOMS • 2007
Scientific Poster Session pressions of NEK, Csk, Cdk4, and Fnk related to proliferation, TRADD and TNF␣ related to differentiation apoptosis, and tyrosine phosphatase were increased, whereas expressions of PLC, Ras, and PKC were inhibited. Conclusion: A close involvement of retinoic acid in the differentiation of ameloblastoma-derived cells to ameloblast-like cells was suggested. References Jernvall J and Thesleff I. Reiterative signaling and patterning during mammalian tooth morphogenesis. Mechanisms of Development 2000; 92:19-29 K. Heikinheimo, K.J. Jee, T. Niini, Y. Aalto, R.-P. Happonen, I. Leivo, and S. Knuutila. Gene Expression Profiling of Ameloblastoma and Human Tooth Germ by Means of a cDNA Microarray. J. Dent. Res 2002; 81:525-530
POSTER 064 Molecular Mechanisms of Hypoxic Response in Head and Neck Squamous Cell Carcinoma Hiroyuki Mizuuchi, DDS, PhD, Japan (Nishiyama M; Mizuuchi H; Yoshiga K) Statement of the Problem: Tumor hypoxia is now recognized as a key determinant of the biologically aggressive malignant phenotype and the therapeutic resistance. Therefore, better understandings of molecular mechanisms of hypoxic response in solid tumors, including head and neck squamous cell carcinoma (HNSCC), may provide improvement of patients’ prognosis. Hypoxia-inducible factor-1 (HIF-1), the key transcription factor under hypoxic conditions, controls a variety of genes, but its detailed functional mechanisms and hypoxia-inducible downstream genes remain unclear in HNSCC. In this study, we tried to clarify the roles of HIF-1 in hypoxic response and identify novel hypoxia inducible genes in HNSCC cell lines. Materials and Methods: Seven HNSCC cell lines, HSC2, HSC3, HSC4, Ca9-22, KOSC2, HO-1-N-1, HO-1u-1, and KB, were obtained from The Japanese Cancer Research Resource Bank. These cell lines were incubated under normoxic (21% pO2) or hypoxic (1% pO2) conditions for 8-24 hours in experiments. HIF-1␣ protein levels and HIF-1 transcription activities were evaluated by immunoblotting analysis using antiHIF-1␣ antibody and transient transfection with hypoxia response element (HRE)-luciferase reporter plasmid and luciferase assays, respectively. Oligomicroarray and real-time RT-PCR were performed for gene expression analyses. Chemosensitivities were evaluated by MTT assays. AAOMS • 2007
Method of Data Analysis: Statistical analyses were performed by student t test or Mann-Whitney U test. Results: We first compared protein expression levels of HIF-1␣ among 7 HNSCC cell lines. The immunoblottings revealed that hypoxic treatment (1% pO2 for 8 hours) drastically increased HIF-1␣ protein in most cell lines but the inductions varied among cell lines. Subsequently, HIF-1 transcription activities in cell lines were evaluated and results demonstrated that hypoxia-induced HIF-1 activity was strongest in HSC2 cells but weakest in Ca9-22 cells. In HSC2, HIF-1␣ proteins were induced most when the cell was cultured under 1-0.1% pO2 conditions. MTT assays showed that sensitivities of HSC2 to 5-FU or CDDP significantly decreased in hypoxic condition. We next performed comprehensive gene expression analyses using an oligonucleotide array (19,881 probes), which demonstrated that 24-hour hypoxic treatment up-regulated 2,638 genes in HSC-2. The upregulated genes in HSC2 included many novel hypoxia-inducible genes, and 4 genes were evaluated for their expression levels in esophageal cancer tissue specimens by real-time RT-PCR. Among them, 3 genes appeared to show significantly higher expression in tumor tissues than in normal ones. Conclusion: We demonstrated that hypoxia significantly induced HIF-1 activity in HIF-1␣ expressing HNSCC cell lines, which strongly affected cell chemosensitivities. We also identified several novel hypoxia inducible genes, which might play some important role in tumor tissues. Further investigations of their functional mechanisms may provide novel diagnostic markers or therapeutic targets of HNSCC. References Carcinogenesis 2003; 24: 1779-1783 Journal of Biological Chemistry 2003; 278: 6816-6823 The EMBO journal 2000; 19: 4298-4309
POSTER 065 Screening of DNA Copy Number Alterations Detected in Oral Squamous Cell Carcinomas Using Array-Based Comparative Genomic Hybridization Kenichiro Uchida, DDS, PhD, Department of Oral and Maxillofacial Surgery, Yamaguchi University School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi, 7558505, Japan (Okafuji M; Mihara M; Mano T; Ueyama Y; Sasaki K) Statement of the Problem: It is widely accepted that various carcinomas, including oral squamous cell carci43.e37