CYP27A1 and squamous cell carcinoma: Our recently described transcriptome signature for Ctx efficacy in cultured models of squamous cell carcinomas (SCCs) revealed that the molecular function of Ctx depended on high expression levels of genes encoding EGFR ligands (such as AREG and EREG) concomitant with downregulation of DUSP-regulated EGFR inhibition (Oliveras-Ferraros et al, 2011a, 2011b).