(j-l) Inverse invasion assay of MDA-MB-231 cells transfected with siRNA oligonucleotides targeting interest genes. Invasive activity is the numbers of cells/field that migrate through Matrigel further than 50 µm (k). Efficacy of targeted gene silencing was verified by qPCR (l). Data are mean ± SD from 3 different fields. Bar, 250 µm. 