Prognostic factor identification by screening changes in differentially expressed genes in oral squamous cell carcinoma.

OBJECTIVE This study was designed to identify changes in the expression of proteins occurring during the progression of oral squamous cell carcinoma (OSCC) and to validate their impact on patient prognosis. MATERIALS AND METHODS The human OSCC cell line UPCI-SCC-040 was treated in vitro with TGF-β1, and transcriptome analysis of differentially expressed genes (DEGs) revealed putative candidates relative to untreated cells. The respective protein expression levels of the most important genes were immunohistochemically validated on a tissue microarray (TMA) containing tissue samples from 39 patients with OSCC and were correlated with disease-free survival (DFS) as the primary clinical endpoint. RESULTS Our univariate Cox proportional hazard regression (CR) analysis revealed significant correlations among positive N stage (local lymph node metastasis, p = 0.04), stearoyl-CoA desaturase-1 (p < 0.01), sclerostin (p = 0.01) and CD137L expression (p = 0.04) and DFS. Stearoyl-CoA desaturase-1 and sclerostin remained the main prognostic factors (p < 0.01) in the multiple CR model. CONCLUSION We identified changes in differentially expressed genes during OSCC progression in vitro and translated the impact of the most deregulated genes on patient prognosis. Stearoyl-CoA desaturase-1 and sclerostin acted as independent prognostic factors in OSCC and could also be interesting candidates for new cancer targeted therapeutic approaches.