Serum phospho-CSE1L levels decline after vemurafenib and sunitinib treatment in mice inoculated with human melanoma xenografts. ELISA analysis of phospho-CSE1L levels in serum samples obtained from NOD SCID mice bearing human A375 melanoma xenografts and fed daily with 75 mg/kg of vemurafenib plus 20 mg/kg of sunitinib or 1 mg/kg of lapatinib as the control for 10 days. Sera were collected from mice 1 day prior to drug administration and 5 days following the onset of drug administration. The ELISA assays were performed two times and showed similar results. The data shown here are representative results. The images in the lower panel are representative images of a mouse treated with vemurafenib/sunitinib and showing tumor necrosis and a mouse from the control group 21 days after drug administration. O.D. optical density.