Knockdown of ESCCAL-1 expression increases apoptosis and reduces invasion in vitro. (A) ESCCAL-1 expression was significantly reduced by three individual small interfering RNAs with maximum ~65% reduction in EC9706 esophageal cancer cells infected with ESCCAL-1 siRNA_1. (B) Apoptosis assay showed EC9706 cells infected with ESCCAL-1_siRNA_1 increased as twice apoptotic cells as control cells. (C) Transwell invasion assay displayed reduced cell migration of ESCCAL-1_siRNA_1 infected EC9706 cells in comparison with control cells. * P < 0.05.