P257 Estradiol, tamoxifen and ICI 182,780 alter a3 and b1 integrin expression and laminin-1 adhesion in oral squamous cell carcinoma cell cultures

208 that is a complication with an increasing incidence and extremely difficult to manage. All authors agree about the close relationship between dental procedures and the onset of AOJ. Thought a lot of cases have been reported in international literature and thought this is a current topics of several meetings in order to extend information also to general dentists and physician, however nowadays no successful therapy has been described as resolutive of this peculiar disease of the jaws. On the bases of our experience, the first step in the management of these patients must be a correct clinical and radiological diagnosis to allow the more fit treatment for the specific situation: kind and duration of drug therapy, the general conditions, the analysis of the oral mucosa, the dental situation, the quality of the cortical and narrow bone, the quantity of the pathological bone, are fundamental parameters useful to divide patients in different groups. In this way is possible to avoid under and/or over treatment and reduce the recurrence of the necrosis. Keywords: bisphosphonate, jaw osteonecrosis, oncological complication P256 Colour digital photography and its impact on pathologists understanding of resection specimen orientation S. Walsh *, T. Mirza, G. Smith, N. Hyde. St. George’s Hospital, UK Confusion over the correct orientation of resection specimens, in oral cavity cancer, may lead to the incorrect reporting of surgical margins which may adversely influence decision making when considering further surgical intervention or adjuvant therapies. Our study aims to reduce the potential errors in pathology specimen orientation by providing the pathologist with an annotated, in situ resection specimen on a colour print, to enhance their ability to orientate the specimen. This is a prospective study utilising colour digital prints of pathology resection specimens in situ, to give the pathologist sufficient anatomical information to enhance their understanding of specimen orientation. The digital prints can be further annotated by hand to enhance clarity. The prints are sent along with a standard pathology request form that will include a written description (± a drawing) of the specimen and any relevant patient information. The pathologist is asked to orientate the specimen according to the written/diagrammatic information provided and to record the ease of doing so on an analogue scale. The same procedure is then repeated with the benefit of the photographic data. This study demonstrates that pathologists find the use of a colour annotated photograph significantly enhances their ability to orientate pathology resection specimens correctly. As part of this ongoing study the use of digital photography in frozen section orientation is also being considered. The images can also subsequently be used in the MDT setting to communicate accurately with those involved in planning radiotherapy to facilitate their understanding of any complex anatomy or location of involved margins in order to optimise their radiotherapy field planning. Keywords: Pathology Specimen, Orientation, photography P257 Estradiol, tamoxifen and ICI 182,780 alter a3 and b1 integrin expression and laminin-1 adhesion in oral squamous cell carcinoma cell cultures K. Nelson *, V. Helmstaedter, C. Moreau, H. Lage. Humboldt-University, Germany Adhesion molecules such as integrins and extracellularmatrix proteins like laminins have been identified to play an important role in cell proliferation, migration and invasion by regulating cell-cell adhesion as well as cell-extracellularmatrix interaction in various cancers including oral squamous cell carcinoma

Poster abstracts, Saturday 19 May (OSCC). In this study, the effect of estradiol (E2), and the E2 antagonists tamoxifen (TAM) and ICI 182,780 (ICI) on the expression of integrins and adhesion to laminin-1 in different OSCC in vitro models was analysed. TAM and ICI inhibited growth in all OSCC cell lines. Dependent on estrogen receptor (ER) status E2 displayed a significant influence on growth after long-term administration. ICI reduced laminin-1 adhesion in all cell lines. b1 integrin transcription is reduced with TAM and E2 and a3 cell-surface expression with TAM. Growth and integrin modulation is displayed in an incoherent manner, suggesting that growth and integrin modulation are influenced by E2, TAM and ICI utilizing different pathways involving ER modulation. The alteration of a3 and b1 integrin as well as growth and adhesion behavior under estrogen and antiestrogen administration allows the supposition that OSCC are estrogen sensitive urging the need to further elucidate the basic mechanisms involved in ER function and its ligands in OSCC. Keywords: Integrin, Estrogen receptor P258 Single nucleotide polymorphism (Arg290Gln) in the coding region of esophageal cancer-related gene-1 (ERCG1) in oral squamous cell carcinoma (OSCC) M. Blessmann *, A. Atac, J. Kaifi, P. Pohlenz, V. Kalinin, R. Schmelzle, J.R. Izbicki, M. Heiland. University Medical Center Hamburg-Eppendorf, Germany Introduction: Recently presence of single nucleotide polymorphisms (SNP) in esophageal cancer related gene-1 (ERCG1) has been described to be a genetic risk factor for esophageal squamous cell carcinoma patients. In this present study, we examined SNP in ERCG1 in oral squamous cell carcinoma. Methods: We retrospectively analyzed SNPs genotypes Arg/Arg, Arg/Gln and Gln/Gln in the ERCG1 coding region by using capillary electrophoresis and DNA sequencing analyses. A total of 109 OSCC-patients were included and 104 healthy controls. The impact of these ERCG1 single nucleotide polymorphisms on risk of developing oral squamous cell carcinoma was examined. Results: Subjects who carried the Arg/Arg were rather at higher risk of developing oral squamous cell carcinoma, with an odds ratio (OR) = 1.64 being 95% confidence interval (CI) = 0.95 2.84. Discussion: These findings indicate that ERCG1 SNPs are a genetic susceptibility factor for oral squamous cell carcinoma. We observed a statisticantly increased risk of OSCC associated with the ECRG1 Arg/Arg genotype compared with the Arg/Gln and Gln/Gln. Keywords: oral squamous cell carcinoma, single nucleotide polymorphism, ERCG1, prognostic marker P259 Proliferative verrucous leucoplakia: a clinico-pathological study of 48 Italian patients S. Capodiferro *, E. Maiorano, A. Lucchese, M.G. Lacaita, G. Favia. University of Bari, Italy Proliferative Verrucous Leukoplakia (PVL) is a unique type of oral leukoplakia characterised by recurrent and multiple lesions that initially show hyperkeratosis at the histological level and subsequently progress to dysplastic lesions and eventually to overt invasive cancer. Attention was called to several different aetiological factors as responsible for PVL, including viral (HPV, EBV) infections, voluptuary habits, poor dietary intake of flavonoids and trauma but no one of the former has been definitely ascertained as the causative agent. We studied a group of 48 patients affected by PVL, who developed at least one OSCC confirmed histologically. The patients were 23 male and 25 female followed minimum for 18 months to a maximum of 240 months. The age range