Metabolic tracer uptake profile upon exposure to PLX4032. a-c) in vitro PET tracer uptake profiles for 11 different melanoma cell lines. Tritium counts was measured on a micro-beta reader and PLX4032 treated cells were compared to vehicle control and relative PET tracer uptake calculated. a) [3H]-thymidine uptake profile, b) [3H]-FAC uptake profile, c) [3H]-FDG uptake profile. The black lines and the number next to them represent the average change in PET tracer uptake of the cell lines with the same mutational status and sensitivity towards PLX4032. d) [18F]FDG PET tracer uptake in vivo. SCID/beige mice with 5-7 mm M249 melanoma xenografts on the left lower flank were treated twice daily with 100 mg/kg of PLX4032 or vehicle control by oral gavage. Three days later mice were imaged by microPET scanning upon administration of [18F]-FDG.