Interruption of Twist expression promoted cell apoptosis.

(A) The apoptotic rates of Twist knockdown cells were moderately increased in contrast to control siRNA transfected and untreated cells. Apoptotic cells were identified by double supravital staining with FITC conjugated Annexin-V and PI. Upper right, late apoptotic cells; lower left, fully viable cells; lower right, early apoptotic cells; upper left, necrotic cells. (B) Depletion of Twist inhibited the invasive ability of lung cancer cells. Cell invasion was examined using cell culture chambers with Matrigel. The representative microscopic fields of invasive cells transfected with Twist and control siRNA, and untreated cells were shown, respectively. The histogram showed that the number of invasive cells (A549 and LTE) transfected with Twist siRNA was significantly fewer (P<0.05) than cells transfected with control siRNA or untreated. Columns, mean (n = 10); bar, SD; *P<0.01.