Pomalidomide induces monocyte migration. (A) Primary monocytes loaded on the upper chamber were incubated with DMSO or 1 μM pomalidomide. M-CSF was loaded on the bottom chamber as chemoattractant. Cells were allowed to migrate for 6 hours, and the migrated cells in the bottom chamber were determined. The amount of cells treated with DMSO is calculated as 100%. (B) Both Rho inhibitor C3 and Rac1 inhibitor decrease pomalidomide-induced monocyte migration. When C3 or Rac1 inhibitors were used, cells were preincubated with the inhibitors for 30 minutes before the addition of DMSO or pomalidomide. The amount of cells treated with DMSO is calculated as 100%. Columns and error bars represent mean (± SEM). Data represent average of 5 independent experiments (Student t test, *P < .05).