Objective: To evaluate the expression of vascular endothelial growth factor (VEGF) and its receptors KDR and Flt1 in patients with acute myeloid leukemia (AML).
Methods: The expression of VEGF and its receptors mRNA was assayed by RT-PCR, the plasma of VEGF by ELISA.
Results: In 13 AML cell lines, the expression of VEGF, KDR and Flt1 mRNA were found in 13 (100%), 7 (53.8%) and 12 (92.3%), respectively. There were 21 (65.6%), 1 (3.1%), and 17 (53.1%) of 31 (AML) patients bone marrow mononuclear cells (BMMNCs) expressing VEGF, KDR and Flt1 mRNA, respectively. None of BMMNCs from 3 normal donor and CD(34)(+) cells from 2 normal donor was found to express VEGF, KDR and Flt1 mRNA. The plasma level of VEGF of 39 patients (new diagnosed, relapsed and secondary-AML) before treatment was (135.3 +/- 87.9) ng/L which was significantly higher than that of 15 complete remission (CR) patients (80.6 +/- 36.9) ng/L and 12 normal donors (80.6 +/- 33.1) micro g/L (P = 0.028, 0.007). The plasma level of VEGF of 15 non-responsive patients was (188.2 +/- 118.6) ng/L after two cycles of chemotherapy which was higher than that of 20 CR patients [(104.2 +/- 30.9) ng/L] (P = 0.004).
Conclusion: VEGF and its receptors KDR and Flt1 mRNAs were expressed in BMMNCs of AML patients. The plasma level of VEGF directly affected the response to chemotherapy in AML patients.