Identification Of Gene Expression Profile Of Laryngeal Squamous Cell Carcinoma

SOUSA-SANTOS P. ¹ , SIMAO T. ² , RIBEIRO PINTO L. ¹

Laryngeal squamous cell carcinoma (LSCC) is a common head and neck cancer, being one of the most incidence tumors in the world, especially in developing countries, such as Brazil. The main risk factors for LSCC are tobacco and alcohol consumption and it usually occurs in patients older than 60 years. Similarly to others head and neck tumors, LSCC is a major health problem because of poor prognosis and slight improvement in the five-year survival during the past four decades. Aiming to better understand the molecular changes present in LSCC, we carried out a gene expression profile analysis using the Affymetrix Human Exon 1.0 ST microarray chip. To this end, 14 tumor tissues were compared with 12-matched non-malignant surrounding mucosa, resulting in 245 up-regulated and 449 downregulated genes in tumor. Principal component analysis and Bayesian hierarchical clustering showed that the global gene expression profile observed in tumors is distinct from that their adjacent mucosa. Enrichment analyses of the differently expressed genes (DEG) were performed in order to understand which molecular changes are occurring and which molecules were responsible for this gene expression profile. Moreover, aiming to identify the main altered cellular signaling pathways, we analyzed our data in KEGG database and was the signaling pathways related to cellular adhesion, drug and xenobiotics metabolism, immune and inflammatory response, pathways related to cancer, among others, were pointed out as the most altered. In addition, the transcription factors regulators analysis identified the transcriptional factors E12, AP1, FOXO4, NFAT, LEF1, CHX10 and MAZ as possible gene expression main regulators in laryngeal tumors. Further, to this purpose, 54 microRNAs were observed as possible candidates involved with the regulation of DEG. Funding Source: Ministério da Saúde; Swiss Bridge.