Expression and prognostic significance of livin/BIRC7 in childhood acute lymphoblastic leukemia.

Livin, a member of the inhibitor of apoptosis proteins has been considered to be a poor prognostic marker in malignancies. However, little is known about the clinical relevance of livin expression in childhood acute lymphoblastic leukemia (ALL). The aim of the present study was to assess the expression of livin on leukemic blasts of de novo childhood ALL and its relevance to clinical and hematological findings, and treatment outcome. The expression of livin was analyzed in 80 patients with newly diagnosed childhood ALL using quantitative reverse transcriptase-polymerase chain reaction. The results of the study revealed that the expression levels of livin were higher in patients with favorable prognostic factors. Furthermore, livin expression was associated with a favorable early response to chemotherapy (leukemic blast <25% day 7 bone marrow response) (P = 0.001). Patients with high livin expression were associated with significantly higher CR rate (P = 0.02) and lower mortality rate (P = 0.05) than those with low livin expression. Kaplan-Meier curves demonstrated that high livin expression was associated with significantly longer DFS (P = 0.004) and overall survival (P = 0.02). Multivariate analysis demonstrated that livin expression was independent favorable prognostic factor for OS and DFS (P = 0.05 and P = 0.01, respectively). This study suggests that livin expression could be a novel prognostic marker in childhood ALL thus it could be incorporated into patient stratification and treatment protocols.