Clinical relevance of circulating vascular endothelial growth factor [VEGF] in patients with acute leukemia and non-Hodgkin's lymphoma

ABSTRACT

Vascular endothelial growth factor [VEGF] is a potent regulatory molecule of the process of new blood vessel formation [angiogenesis]. It is a critical process for tumor growth and metastasis. It might represent a promising therapeutic target in hematologic malignancies. The aim of this study is to assess serum level of VEGF, and its prognostic significance in non-Hodgkin's lymphoma [NHL], acute lymphoblastic leukemia [ALL] and acute myeloid leukemia [AML] patients. VEGF level was assessed in the sera of 47 patients before treatment [NHL; n=20, ALL; n=13, and AML; n=14] and controls [n=13]. Samples were collected again from patients with remission after chemotherapy [25 patients 10 NHL, 8 ALL and 7 AML patients]. Before treatment serum VEGF levels in NHL and AML patients revealed significant elevation compared with control group [P-values 0.048 and 0.032 respectively]. On the contrary, a highly significant reduction of serum VEGF was elicited in ALL patients compared with control group [P= 0.009]. After treatment, the serum VEGF levels were significantly reduced nearly to the control values in NHL and AML patients. ALL patients exhibited increasing trend of serum VEGF level in remission approaching control values. In NHL patients the correlation statistics revealed a significant positive correlation between serum VEGF level and serum LDH, uric acid, ESR, B-symptoms, and BM lymphocytes [P- 1 values 0.007, 0.028, 0.001, 0.003, I and 0.023 respectively]. ALL patients I elicited non-significant correlation between serum VEGF and all other studied parameters. In AML patients, a significant correlation was found between serum VEGF level, and both -ESR [r sr 0.49, P= 0.024] and absoIute neutrophilic count [r = 0.617, P= 0.019]. Serum VEGF levels I showed prognostic information in predicting response to treatment of NHL and AML patients. In ALL patients serum VEGF level could be an early predictor of renewal of normal hematopoiesis after remission induction. Serum level of VEGF may be used to predict clinical outcome and/or monitor treatment of hematologicai malignancy