Yang C-L et al. - Overexpression of Livin protein may play a promoting role in the occurrence and progression of NSCLC. Moreover, it may bring an adverse effect on patients’ prognosis. Although overexpression of Smac protein affects the occurrence and progression of NSCLC, it has no relationship with the prognosis. Livin protein may be helpful to evaluate the progression of NSCLC, and to predict the prognosis.