Impaired miRNA processing–enhanced in vitro invasion requires upregulated uPA expression. (A) Cells were transduced with control lentiviral vector or vector containing Drosha, DGCR8, or Dicer shRNA for 4 days. The population of the transduced cells was detached and analyzed for their ability to invade Matrigel. The invading cells on the undersurface of invasion chambers were stained and counted under a phase-contrast microscope. Data are mean ± SE (n = 3). *P < 0.005 versus control. (B) Scrambled RNA or uPA siRNA pool (5 µM) was transfected into control, Drosha, DGCR8, or Dicer knockdown cells for 3 days and then analyzed for in vitro invasion. Data are mean ± SE (n = 3). #P < 0.05 versus scrambled RNA. *P < 0.005 versus scrambled RNA.