SOX2 and breast cancer: The DEAD-box RNA helicase p72 (DDX17) has been shown to act as transcriptional co-activator for ERα.367 Studies have reported that knockdown of DDX17 results in a significant inhibition of estrogen-dependent transcription of endogenous ERα-responsive genes and estrogen-dependent growth of breast cancer cells.368 Moreover, in ER-positive breast cancer, DDX17 also acts as transcriptional co-activator of SOX2 and upregulates SOX2-mediated stem cell like features.369