Epigenetic inactivation of SOX1 promotes cell migration in lung cancer.

SOX1 is epigenetically inactivated in hepatocellular carcinoma. However, the expression and methylation status of SOX1 in non-small cell lung cancer (NSCLC) remains unknown. The aim of the current study was to investigate whether the promoter hypermethylation of SOX1 is involved in human lung carcinogenesis. We first detected the expression of SOX1 protein in a tissue microarray (TMA) of primary NSCLC and adjacent normal lung tissue specimens using immunohistochemical staining with a specific anti-SOX1 antibody. Methylation of the promoter region of SOX1 in lung cancer tissues was determined by bisulfite sequencing PCR (BSP). In the present study, we found that the SOX1 promoter was fully or partially methylated in 40 of 60 (66.7 %) tumor tissues but not in the majority 15 of 60 (25 %) of normal tissues. A statistically significant inverse association was found between SOX1 methylation status and expression of the SOX1 in tumor tissues (P = 0.003). We further demonstrate that restoration of SOX1 inhibited cell migration by regulating actin cytoskeletal remodeling. Our results suggest that SOX1 is epigenetically silenced in the majority of NSCLC and restoration of SOX1 inhibited cell migration by regulating actin cytoskeletal remodeling in NSCLC.