Figure 2.

RT-PCR of VEGF and FLK-1 mRNA expression. The megakaryocytic cell lines Dami and HEL, as well as ex vivo-generated megakaryocytes (Mk.), expressed mRNA of the three VEGF isoforms (VEGF₁₈₉, VEGF₁₆₅, and VEGF₁₂₁). Only the malignant cell lines simultaneously expressed FLK-1 mRNA. RNA from Dami cells analyzed without reverse transcription (no RT) served as a negative control, and RNA from the cell line HL-60 as a positive control for VEGF expression. Endothelial cells (BMEC) as a positive control expressed only FLK-1.