In breast cancer cells, reduced expression of the circadian gene PER2 was found to correlate with increased expression of the pro-EMT genes Snail Family Transcriptional Repressor 2 (SLUG), Snail Family Transcriptional Repressor 1 (SNAI1), and Twist-related protein 1 (TWIST1) (74). This evidence concerns the gene SNAI2 and breast carcinoma.