SNAI1 and cancer: Several mechanisms were identified to regulate the expression of VDR. Snail1 and Snail2, members of Snail family transcriptional repressor upregulated in may cancers engaged in tumor invasion and metastasis, were revealed to bind to E-boxes in the proximal promoter region of the VDR gene leading to recruitment of co-repressors that strength the VDR transcription in breast and colon cancer cells [94,95,96].