MXD1 and head and neck squamous cell carcinoma: Salehi-Tabar et al. found that in head and neck squamous cell carcinoma, vitamin D receptor (VDR) suppresses c-Myc but enhances Mxd1 expression, and such opposing effect on c-Myc/Mxd1 axis leads to a significant transcriptional inhibition of c-Myc target genes 17.