A498 cells

Renal carcinoma Caki1 and KTCTL-26 cell lines, both derived from a clear cell renal cell carcinoma and von Hippel-Lindau (VHL) positive, were purchased from LGC Promochem (Wesel, Germany). A498 cells with disrupted VHL function were derived from Cell Lines Service (Heidelberg, Germany). The tumor cells were grown and subcultured in RPMI 1640 medium supplemented with 10% fetal calf serum (FCS), 1% Glutamax (all Gibco/Invitrogen, Karlsruhe, Germany), 2% HEPES (2-(4-(2-Hydroxyethyl)-1-piperazinyl)-ethansulfonsäure) buffer and 1% penicillin/streptomycin (both Sigma-Aldrich, München, Germany), at 37 °C in a humidified 5% CO₂ incubator. Subcultures from passages 5–30 were selected for experimental use.
Human umbilical vein endothelial cells (HUVEC), isolated from human umbilical veins, were grown in Medium 199 (M199; Biozol, Munich, Germany), 10% FCS, 10% pooled human serum, 20 μg/mL endothelial cell growth factor (Boehringer, Mannheim, Germany), 0.1% heparin, 100 ng/mL gentamycin and 20 mM HEPES-buffer. Subcultures from passages 2 to 6 were selected for experimental use.

RCC cell lines Caki1 and KTCTL-26 were derived from LGC Promochem (Wesel, Germany). A498 cells were purchased from Cell Lines Service (Heidelberg, Germany), and 786O were obtained from Prof. Wilhelm Krek (Institute of Cell Biology Zürich, Switzerland). The tumor cells were grown in RPMI 1640 medium supplemented with 10% fetal calf serum (FCS), 2% HEPES (2-(4-(2-Hydroxyethyl)-1-piperazine)-ethanesulfonic acid) buffer, 1% Glutamax (all Gibco/Invitrogen, Karlsruhe, Germany), and 1% penicillin/streptomycin (both Sigma-Aldrich, München, Germany) at 37 °C in a humidified 5% CO₂ incubator.

Caki-1 and KTCTL-26 cells were purchased from LGC Promochem (Wesel, Germany) and A498 cells from Cell Lines Service (Heidelberg, Germany). Tumor cells were grown and subcultured in RPMI 1640 medium (Seromed, Berlin, Germany) supplemented with 10% fetal calf serum (FCS), 20 mM HEPES-buffer, 1% glutamax, and 1% penicillin/streptomycin (all: Gibco/Invitrogen; Karlsruhe, Germany) at 37°C in a humidified, 5% CO₂ incubator. Subcultures from passages 5–24 were employed.
Human umbilical vein endothelial cells (HUVEC) were harvested by enzymatic treatment with dispase (Gibco/Invitrogen) and cultured in Medium 199 (M199; Biozol, Munich, Germany), supplemented with 10% FCS, 10% pooled human serum, 20 μg/ml endothelial cell growth factor (Boehringer, Mannheim, Germany), 0.1% heparin, 100 ng/ml gentamycin, and 20 mM HEPES-buffer (pH 7.4). Subcultures from passages 2–6 were employed.