NE attenuates the efficacy of sunitinib in vivo . A) Preoperative preparation for implanting micro-osmotic pumps which should soaked in normal saline for at least 48 hours at 37°C. B) The pumps were implanted subcutaneously on the left back of the mice. C) The photograph of the tumors excised from all mice in 4 groups in B16F1 models. D) The bar chart showing the weight of the tumors. E) The line chart showing tumor growth curves. F) VEGF, IL-8 and IL-6 protein levels measured by ELISA in the serum from the mice in B16F1 models. Data are represented as percentage of the control (SUN without NE or PROP). All bars represent the mean ± SD. SUN, sunitinib. PROP, propranolol. *, P ≤ 0.05; **, P ≤ 0.001.