TWIST1 and neoplasm: In the present study, we demonstrated the following: (1) Twist1 overexpression is significantly associated with reduced survival of NSCLC patients; (2) knockdown of Twist1 suppresses cell invasion, clone formation, and in vivo tumor growth, but overexpression of Twist1 enhances cell invasion and clone formation; (3) knockdown of Twist1 suppresses p-4E-BP1 possibly through p-mTOR inhibition, and Twist1 expression is correlated with p-4E-BP1 expression in NSCLC patients; and (4) a variety of gene expressions are changed after Twist1 knockdown.