Indeed, decreased luciferase activity in a reporter assay showed that the 3′-UTR of Snail mRNA is a direct target of miR-30a in breast cancer cells (Supplementary Figure S2), and this is consistent with a previous report that miR-30a overexpression downregulates Snail and thereby inhibits invasion and metastasis of lung carcinomas [12]. Here, SNAI1 is linked to breast cancer.