Vascular endothelial growth factor in newly diagnosed and recurrent childhood acute lymphoblastic leukemia as measured by real-time quantitative polymerase chain reaction

Purpose: Overexpression. of vascular endothelial growth factor (VEGF) is as sociated with increased angiogenesis, growth, and metastasis in solid tumor s, but to date the significance of VEGF in leukemia has received only limit ed attention. Therefore, this study examined the cellular VEGF levels in 31 newly diagnosed and 22 recurrent cases of childhood acute lymphoblastic le ukemia (ALL). Experimental Design. VEGF was determined with realtime quantitative PCR met hods. Kaplan-Meier statistical analyses were conducted for the relapse-free intervals and the overall survival times. The groups were compared by log- rank and rank-sum tests. Results: The VEGF levels were significantly higher in recurrent ALL compare d with newly diagnosed ALL (28.0 versus 3.1 units; P = 0.001). Kaplan-Meier estimates were conducted to analyze the prognostic value of VEGF levels in newly diagnosed ALL with regard to the relapse-free intervals and the over all survival times. In this analysis, the median relapse-free interval of p atients with low VEGF levels was more than 10 years, whereas the relapse-fr ee interval of patients with high VEGF expression was only 1.2 years. The m edian overall survival time for the collective with low VEGF levels was >10 years, whereas the survival of the group of patients with high VEGF levels was 3.9 years. This difference was not statistically significant. This may be attributable to the small number of patients involved. Conclusion: Our data suggest that VEGF may play an important role in the pa thophysiology of ALL. The expression of VEGF raises the possibility of usin g angiogenesis inhibitors as a novel therapeutic strategy in childhood ALL.