pp084

PP084

MicroRN A and cancer of the tongue Konstantinos Paraskevop oulos a, Panagiota Touplikioti b,George Koloutso s a, Konstantinos Papazisi s c,Alexandro s Lambropoul os d, Konstantinos Vahtseva nos a,Konstantinos Antoniades a

a Department of Oral and Maxillofaci al Surgery, General Hospital, G.Papaniko laou, Thessaloni ki, Greece b Departme nt of Cytopathol ogy, Cancer Hospital, Theagen eion, Thessa- loniki, Greece c Departme nt of Oncology, Euromedi ca General Klinik, Thessaloniki ,Greece d Laboratory of Molecu lar Biology, First Department of Obstetr ics and Gynaecolog y, General Hospital Papageor giou, Thessaloniki , Greece

Purpose : MicroRNAs (miRNAs) are a group of endoge nous, non- coding, 18–24 nucleotide length single-st rand RNAs that regulate gene expression at the post-trans criptional level through mRNA deg- radation or translationa l repression. They are involved in regulatin gdiverse cellular biological process es such as cell cycle, differentiation and apoptosis leading to malignanc ies, including oral squamou s cell carcinoma (OSCC). Altered microRNA expression has been associat edwith both cancer progres sion and metast asis. There are only few mentions about the miRNAs that are expressed in the squamous cell carcinoma of the tongue . The aim of our study is to evaluate whethe rmiRNA expressi on analysis could be used as a diagnost ic tool to dis- cover the primary site of malignanc y, within the tongue.

Materia l and methods: We have collected twelve samples from the tumor and its healthy adjacent tissue of the tongue. We will use miRNA real-time PCR array system to identify miRNA expression profiles of squamous cell carcinoma of the tongue.

Results and conclusio ns: Accordin g to other recent studies small number of dysregula ted miRNAs have been implicated either asoncogenes or tumor suppres sors, affecting the initiation and pro- gression of OSCC through the regulatio n of proliferati on, apoptosis,metastasis and chemor esistance. Also, these misexpress ed miRNAs have been shown to have potential as novel diagnostic, prognostic and therapeuti c tools, which are expected to advance the clinical managemen t of OSCC in the near future.

doi:10.1016/j.oraloncolo gy.2013.03.327

PP085

Study of microRNA s’ expression profile in head and neck cancer Valentina Manciocco a, Barbara Pichi a,b, Federica Ganci b,Giorgia Fontem aggi b, Giovanni Blandino b, Giuseppe Spriano a

a Department of Otolaryngolo gy Head & Neck Surgery, National Cancer Institute ‘‘Regina Elena’’ Rome, Italy b Translation al Oncogen omics Unit, Nationa l Cancer, Institute ‘‘Regina Elena’’ Rome, Italy

Objecti ve: miRNAs’ expressi on profile is emerging among the best markers for diagnosis, staging and treatmen t of cancer. The present project aims at characte rizing miRNAs signatures with prognost ic,predictive or diagnostic power in HNSCC and at identif ying possible correlations with TP53 status.

Method s: Patients with histological ly proven HNSCC who under- went surgical treatment without any previous chemo/radi o-thera- peutic treatment were included in the study. Three biopsies, from the tumor itself, peri-tu moral tissue and normal tissue, were obtained for each patient and submitt ed to RNA and genomic DNA extraction.

Results: TP53 status was assessed in 55 patients, by direct sequenci ng of exons 5–8, and 23 out of these 55 showed TP53 mutation s. Three tumor samples presented double or triple mutation s. TP53 status was also evaluate d in the peri-tu moral and normal counterpa rts and a wild-type TP53 sequence was found inall cases.

Additiona lly, cDNA cloning and subseq uent sequenci ng from samples carrying double and triple TP53 mutation s showed the exis- tence of different allelic population s, suggesting that these tumors are compos ed by TP53-heterogen eous cell types.

microRNAs ’ expressi on profiling was perform ed on 55 patients using the Agilent platform. Nineteen miRNAs are differential ly regu- lated in the HNSCC samples when compared with their normal tissue counterpa rts, while eighteen miRNAs are significantly altered intheir expressi on when compared with their peri-tumoral tissue counterpa rts (using p-value <10 �3 and fold change >2 as cut-off).

Integrat ion between microRNAs’ expression data and TP53 status evidence d four microRNAs whose alteratio n in HNSCC correlates with TP53 inactivation.

Conclusion: The data obtained by TP53 cloning suggest the pres- ence of different clonal populat ions in the tumor. Microa rray analy- sis indicates that microRNAs are strongly modulat ed between HNSCC tumor and non-tum or samples and many of the altered microRNAs in our data. Ongoing analyses are integrati ng microRNAs’expressi on data with clinical informa tion in order to evaluate the predictiv e/prognosti c power of the modulat ed microRNAs.

doi:10.1016/j.oraloncology.20 13.03.328

PP086

An unusual massive gingival enlargem ent – A case report Akhilana nd Chaurasia

Departme nt of Oral Medicin e and Radiolog y, King George Medical Univers ity, Lucknow, Uttar-Pra desh, India

Hereditary gingival fibromatosis (HGF) is a rare condition that can occur as an isolated disease, chromosom al abnormal ity or as part of a number of syndro mes.The gingival enlargement in heredit ary gingival fibromatosis can be so severe that it can cover the crowns of teeth completel y causing severe functional derang ement and facial disfigurement. Through review of literature revealed that HGF is usually an autosomal dominan t condition however the reces- sive forms are also reported.

The hyperpl astic gingiva is firm on palpation and has normal color with abundant stippling on the adjacent gingiva. The buc- cal and lingual gingiva may be involved in both the mandible and maxilla. The degree of gingival enlargemen t shows both intra and inter-indiv idual variations. Here we are presenting aninteresting case report of massiv e Hereditary gingival fibromatosis.

doi:10.1016/j.oraloncology.20 13.03.329

PP087

Myxofibrosarcoma of true vocal cord Yeo-Hoon Yoon

Departme nt of Otolaryngo logy–Head and Neck Surgery, Chungn amNationa l University Hospital, Daesa-Don g, Republic of Korea

Asbtracts / Oral Oncology 49 (2013) S93–S156 S123