miR-31, a well-known anti-metastatic miRNA in breast cancer, was first shown to inhibit breast cancer metastasis both in vitro and in vivo[1] through the targeting of integrin-α5 (ITGA5), radixin (RDX) and RhoA [2] and later through targeting of WAVE3 [3]. The gene discussed is RHOA; the disease is breast carcinoma.