Mechanistically, we show that (1) Gabra3 activates the AKT pathway to promote cell migration and invasion; (2) that A-to-I editing of Gabra3 occurs only in non-invasive breast cancer cells; and (3) that RNA-edited Gabra3 transdominantly suppresses the functions of unedited Gabra3 in promoting cell invasion and metastasis. The gene discussed is GABRA3; the disease is breast cancer.