SOX2 in squamous cell carcinoma: amplifying a pleiotropic oncogene along carcinogenesis.

SOX2 is a master pluripotency controller that was recently identified as a novel major oncogene, recurrently amplified and activated in Squamous Cell Carcinoma (SCC). These studies have used a similar strategy of chromosomal aberrations screening to identify the SOX2 locus as one of the most frequently amplified site over the SCC genome. They have further highlighted the recurrent SOX2 activation and its necessary role for squamous cell survival. Finally, they showed that SOX2 is also involved in the early steps of lung SCC, as participating to transform human bronchial epithelial cells. Furthermore, SOX2 overexpression can induce the expression of the squamous markers p63 and keratin 6, supporting the idea that SOX2 might be implicated in SCC differentiation. In addition, SOX2 overexpression stimulates lung squamous cell migration. However, neither study assessed the impact of the recurrent activation of SOX2 in advanced primary tumors nor how SOX2 may mechanistically participate to tumor progression and aggressiveness. Here we present these studies and additional data from integrative transcriptomic analyses of primary lung SCC that altogether shed new light and open new exciting perspectives on the multiples roles that SOX2 exerts all along SCC carcinogenesis.