Survivin and aven: two distinct antiapoptotic signals in acute leukemias

Antiapoptotic signals are important in the development, progression and prognosis of malignant tumors. The aim of this study was to determine the two distinct antiapoptotic signals-survivin and aven-in acute leukemias and compare them with clinical and hematological findings and response to therapy. Real-time quantitative PCR was used and survivin and aven were detected at the messenger (m)RNA level.

Sixty-five patients with acute leukemia [37 with acute myeloblastic leukemia (AML) and 28 with acute lymphoblastic leukemia (ALL)] were used as the study group and 10 healthy subjects were used as the control group.

Survivin was between 0.0 and 0.829 copy number/cell (median 0.0721, mean 0.5424301909 +/- 0.139799488589) and aven was between 0.0 and 0.853 copy number/cell (median 0.0124, mean 0.070335542 +/- 0.1524685709). We found an important association between survivin and aven (P = 0.000). Both survivin and aven were higher in the study group than in the controls (P = 0.001 and 0.035, respectively). When we compared survivin and aven with other clinical and hematological parameters, there was an important association between survivin and extramedullary involvement (P = 0.033), survivin and alkaline phosphatase (P = 0.06), white blood cell (WBC) count and lactate dehydrogenase (LDH) (P = 0.000), WBC count and uric acid (P = 0.074), hemoglobin level and LDH (P = 0.072), LDH and uric acid (P = 0.057), CD7 expression and survivin (P = 0.097), and CD34 expression and aven (P = 0.058). Response to therapy was evaluated according to the survivin and aven levels. Survivin level was lower in refractory patients as compared with complete responders (P = 0.085). Aven level was higher in patients with relapse as compared with non-relapse patients (P = 0.04). There was no important association between survivin or aven and performance status, lymphadenopathy or organomegaly.

Both survivin and aven are important antiapoptotic signals in acute leukemias, and the association between extramedullary involvement, CD7 expression and CD34 expression, which are important poor prognostic indicators in acute leukemias, suggests that survivin and/or aven may be novel prognostic indicators in acute leukemias. Further studies with a higher number of patients will be more informative.