Identification of a differential expression signature associated with tumorigenesis and metastasis of laryngeal carcinoma

- We quantified the expression of tumorigenesis associated genes in laryngeal tumors.
- A set of 16 genes have been observed to have altered expression in laryngeal tumors.
- 6 most significant of these genes are, TIMP1, COl4A2, C-MYC, SOX4, SPARC and TGFB1.
- c-Myc and SOX4 are significantly downregulated in metastatic tumors.
- Bioinformatic analyses revealed a TGFB1 centered set of upregulated genes.

ObjectivesMetastasis is the most significant prognostic factor for laryngeal carcinoma which necessitates the identification of molecular alterations associated with metastasis. The identification of such molecular alterations will not only prove useful in treatment but also provide insight into mechanisms of cancer metastasis. The studies conducted so far have not specifically focused on metastasis or invasion pathways. Therefore we investigated the expression profiles with a pathway focused approach.Materials and methodsTotal RNA was extracted from 36 laryngeal tumors and paired cancer free tissue. Expression levels of 88 genes were determined using a PCR array system following cDNA synthesis. Obtained data was used for the calculation of altered expression levels, facilitating relevant algorithms. Significant alterations were determined according to their p-value obtained by Student's t-test.ResultsSixteen genes have shown altered expression when compared with adjacent cancer-free tissue. 2 of these 16 genes have shown differential expression in tumors with neck metastasis in respect to non-metastatic tumors.ConclusionWe found that TGFB1, TIMP1, c-Myc, SPARC, COL4A2 and SOX4 show altered expression in laryngeal tumors. c-Myc and SOX4 expression is decreased as laryngeal tumors switch to metastatic phenotype.