Figure 4.

Expression of HGF in CML cells is independent of BCR-ABL1. (A) Expression of Hdc mRNA and Hgf mRNA in Ton.B210-X cells determined by qPCR. Cells were cultured in the presence (DOXY) or absence (CO) of doxycycline (1 µg/ml) for 24 hours to induce BCR-ABL1 and were then subjected to RNA isolation, cDNA synthesis, and qPCR using primers specific for Hdc, Hgf, and Actin. Results show Hdc mRNA expression levels and Hgf mRNA expression levels as copies/10⁵ copies of Actin. Results represent the mean ± SD of three independent experiments. *P < .05. (B) Expression of HGF, HDC and VEGF mRNA in MO7e cells stably transfected with BCR-ABL1 (p210) or with a control vector (CO) determined by qPCR. Cells were cultured in the absence (-GM-CSF) or presence (+GM-CSF) of GM-CSF (100 ng/ml) for 24 hours and were then subjected to RNA isolation, cDNA synthesis, and qPCR using primers specific for HGF, HDC, VEGF, and ABL. Results show HDC and VEGF mRNA levels as percent of ABL mRNA levels and represent the mean ± SD of three independent experiments. *P < .05. (C) Effects of imatinib on expression of HGF, HDC, and VEGF mRNA in KU812 cells. Cells were cultured in the absence (CO) or presence of imatinib (1 µM) for 8 hours and were then subjected to qPCR analysis using primers specific for HGF, HDC, VEGF, and ABL. Results show HGF, HDC, and VEGF mRNA levels as percent of ABL mRNA, and represent the mean ± SD of three independent experiments. (D) Measurement of HGF in supernatants of KU812 cell. Supernatants were obtained after culturing cells in medium with 10% FCS in the absence (CO) or presence of imatinib at 0.1 and 0.5 µM for 24 hours. HGF concentrations were determined by ELISA. Results represent the mean ± SD of three independent experiments.